Field of the invention

A hinge for connecting a first and second planar component, and a trim for reinforcement of an edge of a planar component. The hinge and/or trim may comprise a self-reinforced polymer. The planar components may also comprise a self-reinforced polymer.

Background to the invention

Self-reinforced polymers (or self-reinforced polymeric materials (SRPMs), self- reinforced composites (SRCs), self-reinforced thermoplastic composites or self-reinforced plastics, including self-reinforced polyolefins such as self-reinforced polypropylene) have be found to be a superior product for creation of packaging and transportation items, such as cases, boxes and bags. The self-reinforced polymer is an emerging family of materials, in which the fibre-reinforcement in these materials is a highly orientated version of the same polymer from which the full material matrix is made. For example, self-reinforced polypropylene comprises a polypropylene matrix reinforced with highly orientated polypropylene fibres.

Self-reinforced polymers provide a material with high performance properties (strength and robustness) but less weight than compared to other materials traditionally used for the same purposes. Moreover, self-reinforced polymers can typically be recycled. In contrast to traditional reinforced materials (which include fibres of a different material in a plastic matrix), self-reinforced polymers are a thermoplastic having fibres that can be melted along with the polymer matrix, and thus be re-formed and reused as required.

Although the high strength and stiffness of self-reinforced polymers have particular advantages for forming lightweight and robust packaging and transportation items (such as cases, boxes and bags), it has been found that combining these materials with traditional hinges and edge trim materials (such as those made from nylon webbing) can prove a weak point in the end product. In particular, these regions (which may be particularly exposed to wear and tear) tend to become frayed and damaged before a self-reinforced polymer section of the packaging or transportation item. This is particularly problematic at the position where a webbing or softer fabric is joined to the stiff self-reinforced polymer sections, because the softer and more flexible fabric may rub and wear against an edge of the self-reinforced polymer panel. Thus, it is an objective of the described invention to provide a hinge and a trim which overcomes these drawbacks.

Summary of the Invention

In packaging and transportation items (such as bags, cases and boxes) formed of self-reinforced polymer, the hinge and edge regions have been found to be especially vulnerable to wear. Described below is a hinge and a trim which look to overcome these problems.

The hinge comprises a first and second panel arranged to join two planar components. The planar components may be the walls or sides of the case, bag or box. The first panel may have a single fold, and the second panel may have at least three folds (so that, in some examples, the second panel may form a concertina). The first panel may be affixed to the two planar components, to join the two planar component with the fold arranged between. The second panel may be affixed to the two planar components with at least one fold therebetween. As such, the second panel (which would be arranged on the outside of the hinge when the hinge is ‘closed’) provides a greater extension than the inner panel (which would be arranged on the inside of the hinge when the hinge is ‘closed’).

Said hinge provides a large range of movement yet does not rely on the flexibility of the material from which the first and second panel of the hinge are made. This allows for use of inflexible materials, including self-reinforced polymers. In particular, a portion of a sheet of self-reinforced polymer may be used as the first and second panel. When this is the case, the hinge benefits from the high-strength and lightweight properties of this material, and the hinge may be as robust as the planar portion which it connects. As such, a transportation or packaging item (including a bag, case or box) incorporating the hinge is improved.

It will be understood that, although the term ‘polyolefin’ and ‘self-reinforced polyolefin’ is used throughout this description, this could refer to any thermoplastic composite material or self-reinforced thermoplastic composite material. It could also refer to any polymer or self-reinforced polymer or self-reinforced polymer composite. Particular examples of materials that could be used include polypropylene and self-reinforced polypropylene, or polyethylene and self-reinforced polyethylene. The material could be a self-reinforced polymer woven composite (such as self-reinforced polypropylene woven composite under the trade name Dewforge ^RTM ). In a first aspect there is described a hinge for connecting a first and second planar component, each of the first and the second planar component having a first planar face and a second planar face, comprising: a first panel, having a fold which divides the first panel into a first and second section; a second panel, having at least three folds which divide the second panel into at least four sections; wherein the first section of the first panel is affixed to the first planar face of the first planar component and the second section of the first panel is affixed to the first planar face of the second planar component; and wherein the first section of the second panel is affixed to the second planar face of the first planar component, and the last of the at least four sections is affixed to the second planar face of the second planar component.

The first and second planar components may be panels or wall of a transportation item (such as a case, bag or box). The planar component may be understood to be a substantially planar section that extends in two dimensions over a much greater distance that in a third dimension, such that planar component is relatively flat. The planar component may comprise a series of layers. The planar component will have an upper and a lower planar face: the lower surface of the planar components may be considered a first planar face, and the upper surface of the planar components may be considered a second planar face. The upper and lower planar faces may be considered to be on opposing sides of the planar component. For instance they may be approximately parallel with each other. The depth of the planar component may be considered as the dimension between the first (lower) planar face and the second (upper) planar face.

The first and the second panel may each be a portion of a sheet or layer of suitable material (such as a layer of self-reinforced polyolefin). The first and the second panels each have folds to define or divide the panel into sections or portions. The fold will be understood to be a pivot at which the panel bends over on itself so that one part of it can cover another. The fold may be created by introduction of a score, a groove or a compressed line in the panel, as described below.

The second panel comprises at least three folds. In general, the three folds will be substantially perpendicular to each other, although this is not essential. In one example, the three folds will be arranged such that the second panel could be folded as a concertina (i.e. so that a first and second section, divided by a first fold, bend over on each other; so that the second and a third section, divided by a second fold, bend over on each other; so that the third and a fourth section, divided by a third fold, bend over on each other). Typically, the first and second fold will be arranged to bend in opposite directions, and the penultimate and last fold will be arranged to bend in opposite direction. Furthermore, in general the first and last fold will be arranged to bend in the same direction.

The hinge is configured such that the first panel provides a joining portion between a first planar face of the first planar component and a first planar face of the second planar component. The second panel is arranged such that a first and last section are connected to a second planar face of a respective first and second planar segment, but with any intervening sections folded or concertinaed between, and preferably folded between the edge faces of the first and second planar component. As such, the second panel provides a larger extension and range of motion than the first panel of the hinge. The hinge can be closed so that the first panel is within an inside or acute angle of the hinge pivot, and the second panel is around an outer or obtuse angle of the hinge pivot.

The hinge is highly flexible but does not need to be made from material that is in itself flexible. Accordingly, the first and second panel of the hinge can be formed from especially hardwearing and even slightly stiff materials, such as self-reinforced polymers. Thus the hinge is robust and hard wearing.

Preferably, the same side or face of the first panel in both the first and the second section is affixed to the first and the second planar component. Similarly, the same side or face of the first and last section of the second panel is connected directly to the first and the second planar component.

The first and second planar component each have at least one edge face extending between the first and second planar face. Preferably, when the hinge is in the open position, a second section of the second panel is arranged to abut or oppose the at least one edge face of the first planar component. Preferably, when the hinge is in the open position, a penultimate section of the second panel is arranged to abut or oppose the at least one edge face of the second planar component. In other words, where the second panel comprises four sections, when the hinge is in the open position the four sections are arranged in a T configuration, with the second and third sections bent over each other to form the vertical portion of the T.

Preferably, the first and second planar component each have at least one edge face extending between the first and the second planar face and extending around at least part of the perimeter of the first and the second planar face, wherein a spacing between the first and second fold of the second panel is less than or equal to the dimension of the edge face extending between the first and second planar face of the first planar component. Preferably, the first and second planar component each have at least one edge face extending between the first and the second planar face and extending around at least part of the perimeter of the first and the second planar face, wherein a spacing between the penultimate and the last fold of the second panel is less than or equal to the dimension of the edge face extending between the first and second planar face of the second planar component. In other words, where the second panel comprises four sections, when the hinge is in the open position the four sections are arranged in a T configuration and the vertical section of the T’ does not extend further than the depth of the planar components.

Preferably, the at least three folds of the second panel are substantially parallel.

The folds may extend across the surface of the second panel so as to be approximately in the same direction. The spacing between a first fold and a second fold typically does not vary substantially across the length of the folds.

Preferably, the second panel is stitched to the first panel, the stitching arranged along the fold of the first panel and arranged to extend across a section of the second panel that is between the second and penultimate fold. In other words, the stitching binds or fixes the first and second panel together in a region between the edge of the first and the second planar components. This has been found to increase the stiffness of the hinge, and avoids torsional motion around the pivot. The stitching may further define the preferred pivot point of the hinge in the first and the second panel. Finally, the stitching may ensure correct folding of the second panel when the hinge in the open position.

Preferably, the first and/or the second panel comprises a self-reinforced polymer, self-reinforced polyolefin or self-reinforced thermoplastic composite material. For instance, the panel may be a portion of a layer or sheet of self-reinforced polymer. Self-reinforced polymers are also knowns as self-reinforced composites, self-reinforced plastics or self- reinforced polymeric materials.

Preferably, the first and/or the second planar component comprises a self- reinforced polymer. Preferably, the first and/or second planar component comprises a foam layer covered by a layer of self-reinforced polymer. In other words, the planar component may be a structure comprised of laminated layers of self-reinforced polymer and foam (such as expanded polypropylene, expanded polyethylene, Ethylene-vinyl acetate, polyethylene terephthalate, expanded polystyrene etc.). In one example, each planar component may be formed of a first and second layer of self-reinforced polypropylene, with a layer of expanded polypropylene in between to create a panel from which walls of an item could be formed. Such a planar component offers high strength, less penetrability to puncture, as well as stiffness to give structural stability, and yet have a low weight. As such, this type of planar components may be an ideal component of a transportation item. Preferably, the self-reinforced polymer is a self-reinforced polyolefin. For instance, the self-reinforced polymer in the panel or in the planar component may be self-reinforced polypropylene or self-reinforced polyethylene. The panel may be formed of a portion of a sheet or layer of self-reinforced polymer.

Preferably, each fold comprises a score, a perforation, or a region of heat compression. The score may be a scratch, notch or groove (such as a V shaped groove or similar) formed in one face of the panel, without cutting entirely therethrough. The perforation may be a series of small holes or slits cut through the panel. The heat compression may be a small linear region of the panel that is heated and compressed (for instance by application of a heated metal rod). A score, perforation or groove in each case forms a imperfection or weakness in the panel, to provide a preferred position for a pivot of the fold. Making a fold in this way provides a mechanism for an accurate and repeatable positioning of the fold.

Preferably, the score or the perforation is formed by at least one of: a laser cut, a computer numerical control (CNC) router cut, a water jet cut, a blade cut, milling. Using these methods, the position of the cut can be programmed using computer aided design and manufacture. Each mechanism allows for accurate and precise positioning of the fold. When forming a perforation or score for a hinge, the perforation or score at its deepest point may be 50%, 60% or even 75% of the thickness of the panel or layer in which it is formed. The perforation may form a V-shaped groove. In certain cases, a v-shaped slider cutter or v-shaped blade (or blade having a triangular cross-section) may be used to create the score.

Preferably, a fixture for affixing or bonding the first section and the second section of the first panel, and for affixing or bonding the first section and the last section of the second panel, comprises at least one of: one or more stitches, an adhesive, heat fusion. In other words, the first and second section of the hinge can be connected to the planar components (or walls of the transportation item) by a number of means. Preferably, stitching through the first panel, the planar component and the second panel may be preferred. However, heating localised areas of the panel could also be used, to heat and fuse regions of the panel to a planar component beneath. Alternatively glue could be applied between the panel and the planar component, to stick the pieces together.

Any of the discussion of the features and their benefits above also relates to corresponding features within a method of manufacture, as outlined below.

In a second aspect, there is described a method for manufacture of a hinge for connecting a first and second planar component, each of the first and the second planar component having a first planar face and a second planar face, the method comprising: forming a fold in a first panel, the fold dividing the first panel into a first and a second section; forming at least three folds in a second panel, the at least three folds dividing the second panel into at least four sections; affixing or bonding the first section of the first panel to the first planar face of the first planar component; affixing or bonding the second section of the first panel to the first planar face of the second planar component; affixing or bonding the first section of the second panel to the second planar face of the first planar component; and affixing or bonding the last section of the at least four sections to the second planar face of the second planar component.

The first and second planar component may each have at least one edge face extending between the first and the second planar face and extending around at least part of the perimeter of the first and the second planar face. Preferably, the method further comprises arranging a second section of the second panel to abut the at least one edge face of the first planar component. Preferably, the method also comprises arranging a penultimate section of the second panel to abut the at least one edge face of the second planar component.

The first and second planar component may each have at least one edge face extending between the first and the second planar face and extending around at least part of the perimeter of the first and the second planar face. Preferably, the method comprises providing a spacing between the first and second fold of the second panel that is less than or equal to the dimension of the edge face extending between the first and second planar face of the first planar component.

The first and second planar component may each have at least one edge face extending between the first and the second planar face and extending around at least part of the perimeter of the first and the second planar face. Preferably, the method may comprise providing a spacing between the penultimate and the last fold of the second panel to be less than or equal to the dimension of the edge face extending between the first and second planar face of the second planar component.

Preferably, forming the at least three folds of the second panel comprises forming the at least three folds to be substantially parallel.

Preferably, stitching the second panel to the first panel by arranging the stitching to extend along the fold of the first panel, and arranging the stitching to extend along a section of the second panel between the second and penultimate fold. Preferably, the first and/or the second panel comprises a self-reinforced polymer.

Preferably, the first and/or the second planar component comprises a self- reinforced polymer. Preferably, the first and/or second planar component comprises a panel formed of a foam layer covered by a layer of self-reinforced polymer.

Preferably, the self-reinforced polymer is a self-reinforced polyolefin. In one example, the self-reinforced polyolefin is self-reinforced polypropylene.

Preferably, forming each fold comprises forming a score, forming a perforation, or applying a region of heat compression. The score may be formed as a notch or groove in the surface of the panel, which does not extend through the entire depth of the panel. The perforation my comprise a series of holes or cuts arranged through the panel. The region of heat compression may be formed by pressing a hot rod or blunt blade into the surface of the panel.

Preferably, forming the score or the perforation is by at least one of: laser cutting, computer numerical control (CNC) router cutting, water jet cutting, blade cutting, milling. When forming a perforation or score for a hinge, the perforation or score at its deepest point may be 50%, 60% or even 75% of the thickness of the panel or layer in which it is formed. The perforation may form a V-shaped groove.

Preferably, affixing or bonding the first section and second section of the first panel, and affixing or bonding the first section and the last section of the second panel comprises at least one of: stitching, application of an adhesive, applying heat to fuse.

Traditionally, a raw edge of a panel or planar component forming a bag, case or box is covered with a trim to prevent wearing, fraying or delamination of the panel or planar component to which it trims. Such trim can also improve the aesthetic appearance of the item. Typically a webbing or material binding has been used for this purpose, being flexible and easy to shape and bind to the panel or planar component 9which may up the walls of a bag, box or case). However, such trims have been found to wear at a greater rate than the planar component itself, and can be a region of vulnerability that can shorten the period of use of an item. This is especially the case when the fabric binding (such as a nylon material) is used for the trim in combination with planar components of self-reinforced polymer (which are stiff and especially hard wearing). In these cases, the trim may rub against the stiff edge of the self-reinforced polymer, providing a place of particular wear.

As such, there is described here a trim formed of self-reinforced polymer. However, the inventors have recognised that the trim must be configured in a non-standard way, to take into account the lack of flexibility inherent in the self-reinforced polymer material.

In particular, the trim is formed from a panel of self-reinforced polymer, configured with two folds which allow the trim to wrapped around the edge of the planar component. In an example, the folds extend substantially parallel to each other across a panel forming the trim, and are then folded to be substantially right-angled. The trim formed in this way in self-reinforced polymer is hard wearing and robust, but light weight. Moreover, the trim provides a precise edge which can be configured to fit the thickness of the planar component to low tolerances. When stacking multiple planar components edged by such a trim, the planar components and their trim can be aligned neatly and uniformly, without wasted space.

In a third aspect, there is described a trim, for reinforcement of an edge of a planar component, the planar component having a first planar face and a second planar face, the planar component further comprising at least one edge face extending between the first and the second planar face and extending around at least part of the perimeter of the first and the second planar face, the trim comprising: a panel of self-reinforced polymer, the panel having a first and a second fold which divide the panel into a first, a second and a third section; wherein the first section is affixed to the first planar face of the planar component; and wherein the third section is affixed to the second planar face of the planar component, such that the second section abuts at least a portion of the at least one edge face of the planar component.

The planar component may be a panel or wall of a transportation item (such as a case, bag or box). The planar component may be understood to be a substantially planar section that extends in two dimensions over a much greater distance that in a third dimension, such that the planar component is relatively flat. The planar component may comprise a number of layers. The lower surface of the planar components may be considered a first planar face, and the upper surface of the planar components may be considered a second planar face. The distance between the first and second planar face may be considered the depth of the planar component.

The panel may be a portion of a sheet or layer of suitable self-reinforced polymer material (such as a layer of self-reinforced polyolefin). The panel has folds to define or divide the panel into sections or portions. The fold will be understood to be a pivot at which the panel bends over on itself so that one part of it can cover another. The fold may be created by introduction of a score, a groove or a line of compression line in the panel, as described below.

The trim has two substantially parallel folds arranged in the panel, which may be a strip or portion of the self-reinforced polymer material. The folds define in the panel, or separate the panel into, three sections. When the trim is attached around the edge of the planar component, the folds may each be bent to around a right-angled position, such that the section of the trim between the folds abuts the edge face of the planar component, and the first and third section of the trim each extend across (and are affixed to) a planar face of the planar component. The fold may then define a right-angled corner around the perimeter of each face of the planar component.

Preferably, the first and the second fold are substantially parallel, and wherein the spacing between the first and the second fold is substantially the same as the dimension of the edge face extending between the first and second planar face of the second planar component. Ideally, this means that the trim wraps around the edge of the planar component without excess, and to closely fit the depth of the planar component. This provides a neat and precise edge for the planar component, which has advantages when the planar components are stacked on top of each other.

Preferably, the planar component comprises a self-reinforced polymer. Optionally, the planar component comprises a foam layer covered by a layer of self-reinforced polymer. In other words, the planar component may be a structure comprised of laminated layers of self-reinforced polymer and foam (such as expanded polypropylene). In one example, each planar component may be formed of a first and second layer of self- reinforced polypropylene, with a layer of expanded polypropylene in between to create a panel from which walls of an item could be formed.

In an alternative, the planar component comprises a layer of foam, wherein the panel of the trim is arranged around the edge of the layer of foam, and then a first further self-reinforced polymer layer is arranged over the first section of the panel of the trim and the foam layer, and a second further self-reinforced polymer layer is arranged over the third section of the panel of the trim and the foam layer. In other words, the first and second section of the trim and the planar component (comprising a foam layer) are sandwiched between two further layers of self-reinforced polymer.

Self-reinforced polymers are also knowns as self-reinforced composites, self- reinforced plastics or self-reinforced polymeric materials. Preferably, the self-reinforced polymer is a self-reinforced polyolefin. For instance, the self-reinforced polymer in the panel or in the planar component may be self-reinforced polypropylene or self-reinforced polyethylene. The self-reinforced polymer may be used as a portion of a sheet or layer.

Preferably, each fold comprises a score, a perforation, or a region of heat compression. The score may be a scratch, notch or groove (such as a V shaped groove or similar) formed in one face of the panel, without cutting entirely therethrough. The perforation may be a series of small holes or slits cut through the pane. The heat compression may be a small linear region of the panel that is heated and compressed (for instance by application of a heated metal rod). A score, perforation or groove forms a imperfection or weakness in the panel, to provide a preferred position for a pivot of the fold. Making a fold in this way provides a mechanism for an accurate and repeatable positioning of the fold.

Preferably, the score or the perforation is formed by at least one of: a laser cut, a computer numerical control (CNC) router cut, a water jet cut, a blade cut. Using these methods, the position of the cut can be programmed using computer aided design and manufacture. Each mechanism allows for accurate and precise positioning of the fold. When forming a perforation or score for a hinge, the perforation or score at its deepest point may be 50%, 60% or even 75% of the thickness of the panel or layer in which it is formed. The perforation may form a V-shaped groove.

Preferably, affixing the first section to the first planar face of the planar component and affixing the second section to the second planar face of the planar component, may use at least one of the following types of fixture: one or more stitches, an adhesive, heat fusion. In other words, the first and second section of the hinge can be connected to the planar components (i.e. the walls of a packaging or transportation item) by a number of means. Preferably, stitching through the first panel, the planar component and the second panel may be preferred. However, heating localised areas of the panel could also be used, to heat and fuse regions of the panel to a planar component beneath. Alternatively glue could be applied between the panel and the planar component, to stick the pieces together.

Any of the discussion of the features and their benefits described above also relate to the corresponding features within a method of manufacture, as outlined below.

In a fourth aspect there is described a method for manufacture of a trim for reinforcement of an edge of a planar component, the planar component having a first planar face and a second planar face, the planar component further comprising at least one edge face extending between the first and the second planar face and extending around at least part of the perimeter of the first and the second planar face, the method comprising forming a first and a second fold in a panel of self-reinforced polymer, the first and the second fold dividing the panel into a first, a second and a third section; affixing or bonding the first section to the first planar face of the planar component; and affixing or bonding the third section to the second planar face of the planar component, such that the second section abuts at least a portion of the at least one edge face of the planar component.

Preferably, the method comprises forming the first and second fold in the panel of self-reinforced polymer so as to be substantially parallel. Preferably, the spacing between the first and second fold is substantially the same as the depth of the edge face extending between the first and second planar face of the second planar component.

Preferably, the planar component comprises a self-reinforced polymer. Optionally, the planar component comprises a foam layer covered by a layer of self-reinforced polymer.

Preferably, the self-reinforced polymer is a self-reinforced polyolefin.

Preferably, forming each fold comprises forming a score, forming a perforation, or applying a region of heat compression.

Preferably, forming the score or the perforation is by at least one of: laser cutting, computer numerical control (CNC) router cutting, water jet cutting, blade cutting. When forming a perforation or score for a hinge, the perforation or score at its deepest point may be 50%, 60% or even 75% of the thickness of the panel or layer in which it is formed. The perforation may form a V-shaped groove.

Preferably, affixing the first section to the first planar face of the planar component and affixing the second section to the second planar face of the planar component, comprises at least one of: stitching, application of an adhesive, applying heat to fuse.

In another aspect, there is a method for forming a hinge, the method comprising: providing a laminated panel comprising at least a layer of foam and a layer of self- reinforced polymer; forming a valley in a surface of the laminated panel, to form the valley in the layer of foam of the laminated panel.

Preferably, the valley is not formed in, or does not penetrate, the layer of self- reinforced polymer. The deepest point of the valley may provide the pivot for the hinge. When the hinge is closed (in other words, when the laminated panel is folded at the hinge), the walls of the valley may come together to face each other and may be in direct contact.

Preferably, the layer of self-reinforced polymer is a first layer of self-reinforced polymer, and wherein the laminated panel further comprises a second layer of self- reinforced polymer, arranged so that the layer of foam is between the first and the second layer of self-reinforced polymer. Preferably, forming the valley comprises forming the valley through the second layer of self-reinforced polymer to form the valley in the layer of foam of the laminated panel. In other words, the valley cuts through the second layer of self-reinforced polymer and into the foam layer. Preferably, the valley is not formed in, or does not penetrate, the first layer of self-reinforced polymer. In other words, the valley does not extend beyond the thickness of the foam and into the first layer of self-reinforced polymer.

Preferably, the valley extends linearly across the laminated panel. Preferably, the valley comprises a V-shaped cut-out, although a ‘u’-shaped cut-out could also be used. In particular, the valley is V-shaped when the laminated panel is arranged so that the first layer of self-reinforced polymer is flat. A v-shaped cut-out for the valley may provide greater structural stability at the hinge, as the faces of the v-shaped valley will abut each other (or make contact) in the folded position of the hinge.

Preferably, when the laminated panel is arranged such that the first layer of self- reinforced polymer is flat, the intersecting planes of walls of the valley are arranged having an angle, >8=180 -N degrees therebetween, wherein N is the angle between a first and second portion of the laminated panel when the hinge is folded. The first and second portion of the laminated panel are separated by the hinge.

Preferably, when the laminated panel is arranged such that the first layer of self- reinforced polymer is flat, the intersecting planes of walls of the valley are arranged having an angle of 85 to 95 degrees therebetween. Preferably, when the laminated panel is arranged such that the first layer of self-reinforced polymer is flat, the intersecting planes of walls of the valley are arranged having an angle of 90 degrees therebetween. For instance, this provides an angle of 90 degrees between a first and second portion of the laminated panel when the hinge is folded. Preferably, when the laminated panel is arranged such that the first layer of self-reinforced polymer is flat, the intersecting planes of walls of the valley are arranged having an angle of 60 degrees therebetween. For instance, this provides an angle of 120 degrees between a first and second portion of the laminated panel when the hinge is folded.

Preferably, after forming the valley, the method further comprises providing a lining layer to cover at least the walls of the valley. Preferably, the lining layer is a nylon fabric. The lining layer may provide a layer at the internal face of a box or case formed using the hinge. For instance, this may provide a soft protective layer at an inner surface of a case or cover.

Preferably, the first and/or the second layer of self-reinforced polymer is each formed from two or more consolidated layers of self-reinforced polymer. The first and/or the second layer of self-reinforced polymer may be formed of a plurality of consolidated layers of the self-reinforced polymer. The number of consolidated layers may be between 2 and 12 layers.

Preferably, the valley is formed via one of: cutting using a blade, cutting using a laser, a cutting using a hot wire; compression using heat and pressure. For instance, the valley may be cut using a sliding guillotine. The valley may be formed using a press wherein the jaws of the press create heat and pressure, as described in other aspects above. Methods of forming the valley that cause heating at the walls of the valley will cause melting of the foam material, which may be beneficial for sealing pores within the foam.

In a further aspect, there is described a hinge, comprising: a valley formed in a surface of a laminated panel, the laminated panel comprising at least a layer of foam and a layer of self-reinforced polymer; wherein the valley is formed in the layer of foam of the laminated panel.

Preferably, the valley is not formed in, or does not penetrate, the layer of self- reinforced polymer. The deepest point of the valley may provide the pivot for the hinge. When the hinge is closed (in other words, when the laminated panel is folded at the hinge), the walls of the valley may come together to face each other and may be in direct contact.

Preferably, the layer of self-reinforced polymer is a first layer of self-reinforced polymer, and wherein the laminated panel further comprises a second layer of self- reinforced polymer, arranged so that the layer of foam is between the first and the second layer of self-reinforced polymer. Preferably, the valley is formed through the second layer of self-reinforced polymer to form the valley in the layer of foam. Preferably, the valley does not penetrate through or into the first layer of self-reinforced polymer.

Preferably, the valley extends linearly across the laminated panel. The valley may be straight or linear.

Preferably, the valley comprises a V-shaped cut-out, or may comprise a ‘u’-shaped cut-out.

Preferably, when the laminated panel is arranged such that the first layer of self- reinforced polymer is flat, the intersecting planes of walls of the valley are arranged having an angle, b = 180-L/ degrees therebetween, wherein N is the angle between a first and second portion of the laminated panel when the hinge is folded. Preferably, when the laminated panel is arranged such that the first layer of self-reinforced polymer is flat, the intersecting planes of walls of the valley are arranged having an angle of between 85 to 95 degrees therebetween. Preferably, when the laminated panel is arranged such that the first layer of self-reinforced polymer is flat, the intersecting planes of walls of the valley are arranged having an angle of 90 degrees therebetween. This creates an angle of 90 degrees between the first and second portion of the laminated panel when the hinge is folded. Preferably, when the laminated panel is arranged such that the first layer of self- reinforced polymer is flat, the intersecting planes of walls of the valley are arranged having an angle of 60 degrees therebetween. This creates an angle of 120 degrees between a first and second portion of the laminated panel when the hinge is folded.

Preferably, the hinge further comprises a lining layer covering at least the walls of the valley. Preferably, the lining layer is a nylon fabric or a felt fabric. Preferably, the first layer of self-reinforced polymer is formed from two or more consolidated layers of self-reinforced polymer. Preferably, the second layer of self- reinforced polymer is formed from two or more consolidated layers of self-reinforced polymer.

In a still further aspect there is a packaging or transportation item, comprising the hinge as described above.

In another aspect, there is a method for forming a hinge in a panel of self-reinforced polymer, comprising: applying heat and/or pressure to at least one area on a surface of a panel of the self-reinforced polymer, to heat at least one portion of the panel at the at least one area to a temperature above or equal to a melting point of the at least one portion; causing the at least one portion of the panel to cool to a temperature below the melting point; wherein the at least one area is arranged on the surface of the panel of self- reinforced polymer at the required position of the pivot of the hinge.

The hinge is formed in a planar sheet or panel of self-reinforced polymer or self- reinforced polyolefin material. It will be understood that any self-reinforced polymer (also known as self-reinforcing polymer, or self-reinforced polymer composite, or self-reinforced thermoplastic composite material) or any self-reinforced polyolefin material could be used.

It will be understood that the self-reinforced polymer discussed here is formed of stretched, molecularly oriented strands or fibres of the polymer material, for example of polypropylene or other crystalline or semi-crystalline thermoplastic material. After a layer, sheet or panel of self-reinforced polymer has been thermo-compressed, the highly oriented strands or fibres of the polymer are embedded in a matrix of the same polymer (wherein the matrix is not highly oriented). For example, self-reinforced polypropylene comprises fibres of polypropylene embedded in a polypropylene matrix.

Two main methods can be used for processing of self-reinforced polymer composites. In a first method, hot compaction is used, in which aligned fibres or stands of the polymer (perhaps woven into tapes or sheets) are layered. The layers are compressed together and heated to a precise temperature. This heating results in melting of only the outer layer or ‘skin’ of each strand or fibre, which has a lower melting point than the core of the strand or fibre. Heating causes around 10% of the strand or fibre to melt (at its outermost surface), and the applied pressure causes the molten polymer to flow around and between the fibres to form a continuous matrix. Once cooled, the polymer material of the matrix solidifies, and contains the strands or fibres. This method results in rigid sheets of self-reinforced polymer material. A second method that can be used is co-extrusion. In this process, fibres or strands of the polymer in a highly-oriented form can be formed by extrusion. In addition, another grade of the same polymer can be extruded or coated on the surface of each fibre or strand. The polymer used for coating each strand is a lower melting point grade of the polymer than the higher melting point grade of the same polymer used for the fibres. As such, this results in coated stands of the same polymer material, which can be woven to form a fabric. The fabric may be heated and compressed after weaving, such that the outer coating of each strand or fibre (comprising the lower-melting point type of the same polymer) melts, but the core of each strand remains solid. Compression during heating again causes the melted polymer of the outer coating to flow, and form a matrix in which the strands of the polymer are contained.

In view of these methods of forming the self-reinforced polymer, the panel of self- reinforced polymer will comprise strands of the polymer either woven or bonded, wherein each strand is surrounded by polymer of the same type but having a slightly lower melting point. Each panel comprises at least one layer of self-reinforced polymer strands, being woven or bonded via a matrix. The difference in temperature of the melting point of the polymer material surrounding each of the strands or cores may be close to the melting point of the cores of the strands (with just a few degrees Celsius difference), and so precise heating will be required to avoid melting of the core material.

The melting temperature may be reached by application of heat and/or pressure. The melting temperature (or melting point) is the temperature that a material changes from solid to liquid. Cooling below the melting point causes the material to return to a solid.

Preferably, the least one portion of the panel comprises a polymer material surrounding one or more reinforcing fibres of the self-reinforced polymer. Here, the at least one portion of the panel is the at least one portion heated to a temperature above or equal to its melting point. For example, the polymer material surrounding one or more reinforcing fibres may be the polymer matrix material, meaning a polymer of the same type as the polymer fibres, but that is not molecularly aligned and which encases or contains the fibres. Alternatively, the polymer material surrounding one or more reinforcing fibres may be a coating on the outer surface of each polymer fibre, which, when melted under compression and then cooled, could form a polymer matrix encasing the fibres. Said coated fibres may be woven together to form a panel (prior to forming the polymer matrix), so that the panel is not necessarily already heated and compressed so as to have formed the polymer matrix. Therefore the self-reinforced polymer panel may have the polymer matrix already formed, or merely be woven. The least one portion of the panel (being the polymer material surrounding one or more reinforcing fibres) that is heated to a temperature above or equal to its melting point will be the same type of polymer as used to form the fibres of the self-reinforced material. However, the least one portion of the panel that is heated to a temperature above or equal to its melting point will be of a different grade of the polymer, and have a lower temperature melting point, than the grade of the polymer used for forming the polymer fibres.

In one example, the self-reinforced polymer is self-reinforced polypropylene. In other words, the self-reinforced polypropylene has highly oriented polypropylene strands or fibres surrounded by polypropylene (being either a polypropylene coating on the strands, or the strands being encased in a polypropylene matrix). Typically, the highly oriented polypropylene strands or fibres have a higher melting point than the surrounding polypropylene material. Preferably, in this case, the heat and/or pressure are applied to heat the at least one portion of the panel (being the surrounding polypropylene material) at the at least one area to a temperature of 90°C to 200°C. More preferably, the at least one portion of the panel at the at least one area is heated to a temperature of 140°C to 200°C, or to 140°C to 180°C.

Preferably, the pressure applied is a pressure of 0.5 to 5 tonne, or more preferably 2 to 4 tonne.

Preferably, applying heat and/or pressure comprises applying heat and pressure, and causing the at least one area to cool comprises cooling the at least one area (or allowing the at least one area to cool) whilst maintaining the pressure applied to the at least one area. The cooling may be active (in other words, via applied cooling means such as fan cooling), or non-active (allowing the temperature to reduce as heat is transferred to the surroundings). Cooling causes any melted portion of the panel to return to its solid form. Maintaining applied pressure during cooling causes any melted portion to flow, and thereby surround fibres of the panel to create a polymer matrix. The applied pressure also causes any melted portion to solidify in a shape determined by the press applying the pressure.

Preferably, applying heat and/or pressure comprises compressing the at least one area between a cooperating first and second portion of a press, wherein the first and/or second portion of the press is heated. The first and second portion may form part of the jaws of a press, for instance. The first and second portion of the press may apply steady and consistent heat to the self-reinforced polymer panel. The first portion may be a bed (such as a flat metal bed, or a planar metal bed having raised contours to cooperate with the second portion). The second portion may comprise a metal pressing ram or rod, or may be a plate having contours or protuberances. The first and second portion may be cooperating such that bringing together of the first and second portion compresses the at least one area therebetween. The first and/or second portion may be actively heated (via internal heating elements, so that a predefined temperature is maintained throughout the process) or may be heated prior to the contact with the panel but without continuous heating throughout the pressing. The panel may be held in the press during cooling of the panel, so that pressure is maintained even whilst heat is allowed to transfer away from the panel.

Preferably, the at least one area is a linear series of two or more areas on the surface of the panel. In other words the heated areas may create dots or dashed regions extending across the surface of the panel.

Preferably, the at least one area is at least one linear area extending across the surface of the panel. In other words, a continuous, linear area is heated and/or compressed.

Preferably, the panel of self-reinforced polymer is formed from a plurality of layers of self-reinforced polymer. As noted above, a panel of polymer may comprise one layer or multiple layers of self-reinforced polymer. Each layer may be formed, according to the processing methods described above, as a layer of highly oriented fibres of a polymer embedded in a matrix of the same polymer, or as a woven layer of highly oriented fibres of the polymer each coated in a lower-melting temperature grade polymer of the same type.

In order to increase the thickness of the panel, multiple of the described layers may be laminated. In one example, multiple layers can themselves be heated and compacted together to form a panel, plate or multi-layer lamina. In this case, the lower melting- temperature grade polymer (being the polymer matrix between fibres in each layer, or surrounding each fibre in a woven layer) will be melted, compressed, and re-solidified in the process of forming the multi-layer panel, in order to bond the layers.

Typically, to generate such a laminated panel, prior to any further described processing steps to form a hinge, the plurality of layers of the self-reinforced material are compressed under heat, in order to melt and join or consolidate the layers to form the panel. As such, in the presently described hinge, prior to the step of applying heat and/or pressure, a plurality of layers of self-reinforced polymer may be heated and compressed to consolidate the plurality of layers to form the panel.

However, as an alternative, the panel may be formed from the plurality of layers of the self-reinforced polymer at the same time as formation of the hinge. In this case, a plurality of layers of the self-reinforced material are arranged in a stack, and during the step of applying heat and/or pressure at the at least one area to form a hinge, heat and or pressure also may be applied across the whole surface of the plurality of layers. Greater pressure and/or temperature may be applied at the at least one area of the required position of the pivot of the hinge (for example, by use of a patterned press). In this way, the panel (comprising a plurality of eventually consolidated layers of the self-reinforced polymer) may be heated and compressed at the same time as the formation of the hinge.

It should be noted that the time during which the heat and/or pressure are applied may be adjusted in view of the thickness of the panel (and the number of layers of self- reinforced polymer therein), as well as the particular polymer material and its melting point. In particular, as the heat is applied at only a top and or bottom surface of the panel of self- reinforced polymer (which may comprise a stack of layers), in a panel having more layers a greater amount of time will be required for sufficient heat to transfer through all layers of the panel to reach a sufficiently high temperature above or equal to the melting point of the polymer material surrounding the fibres. Thus, thicker panels (with a greater number of layers of self-reinforced polymer) may require heat and/or pressure to be applied for a longer period of time. The amount of time for which heat and pressure is applied will vary from tens of seconds to a number of minutes, depending on the composition of the structure that is being thermo-compressed.

Preferably, prior to applying heat and/or pressure, the method further comprises: arranging a planar component on the panel of self-reinforced polymer; and wherein applying heat and/or pressure further comprises simultaneously applying heat and/or pressure to at least one area on the surface of the planar element, the at least one area on the surface of the planar element being aligned with the at least one area on the surface of the panel of self-reinforced polymer, the application of heat and/or pressure simultaneously heating the at least one portion of the surface of the panel at the at least one area to a temperature above or equal to the melting point of the at least one portion, and heating the at least one area on the surface of the planar element to a temperature above or equal to a melting point of the planar element.

The planar element may be a sheet, layer or portion of foam, or may be another layer of thermoplastic material. In an example, the planar element is polymer foam, such as a layer of expanded polypropylene.

The planar element may be arranged on the panel of self-reinforced polymer and then pressed and heated simultaneously with the panel. For instance, this may be by placing both the panel and the planar element between the jaws of a press, which then compresses and heats the panel and planar element. In this way, at least one area of the planar element that is directly underneath or in contact with the at least one area of the panel is heated and pressed together with the at least one area of the panel.

By this method, a hinge may be formed in a layered material, for instance comprising a layer of foam and a layer of self-reinforced polymer. Appropriate selection of the shape of the jaws of a press forming the hinge can allow the shape of the hinge to be modified. In particular, after cooling, the region of the material at the hinge may be thinner (compressed) compared to the regions of material to which heat and pressure were not applied. In part, this may be due to melting of the foam layer, and removal of air pockets in the section of the foam that is heated. The shape of a ‘groove’ generated at the pivot of the hinge can be adjusted according to the shape of the press used to form the hinge. For instance, this may be useful to create a ‘v-shaped’ hinge having a certain angle between faces, so that the hinge can demonstrate a certain angle of opening.

Preferably, causing the at least one portion of the panel to cool to a temperature below the melting point further comprises causing the planar element to cool to a temperature below its respective melting point.

Preferably, the panel of self-reinforced polymer is a first panel of self-reinforced polymer, and prior to applying heat and/or pressure the method further comprises: arranging a second panel of self-reinforced polymer on top of the planar element, so that the planar element is between the first and the second panel of self-reinforced polymer; and wherein applying heat and/or pressure further comprises simultaneously applying heat and/or pressure to at least one area on the surface of the second panel of self- reinforced polymer, the at least one area on the surface of the second panel of self- reinforced polymer being aligned with the at least one area on the surface of the first panel of self-reinforced polymer and with the at least one area on the surface of the planar element, the application of heat and/or pressure simultaneously heating at least one portion of the first panel at the at least one area and at least one portion of the second panel at the at least one area to a temperature above the respective melting point of the at least one portions, and heating the at least one area on the surface of the planar element to a temperature above or equal to the melting point of the planar element.

In other words, a hinge may be formed in a section having a planar element in between (‘sandwiched between’) two panels of self-reinforced polymer. This may be beneficial in configurations where the hinge is likely to undergo wear, as the robust, high impact layer of self-reinforced polymer is present at all outer surfaces of the hinge. In this case, heat and pressure may be applied simultaneously to all layers in the structure (in other words, to at least one area of the first panel, at least one area of the planar element, and at least one area of the second panel simultaneously). This may be via compression between the heated jaws of a press. Heat is transferred from the jaws of the press through the layers, to cause the at least one area of each layer between the jaws to be heated, causing melting of at least one portion of each of the first and second panel, and melting of at least a portion of the foam at the at least one area. Subsequently, the section is caused or allowed to cool (typically, whilst remaining under compression) resulting in a compressed region which acts as a hinge, but which is also a join.

Preferably, causing the at least one portion of the panel to cool to a temperature below the melting point comprises causing the at least one portion of the first panel and the at least one portion of the second panel to cool to a temperature below their respective melting point, and causing the planar element to cool to a temperature below its melting point.

Preferably, the panel of self-reinforced polymer is a first panel of self-reinforced polymer, and prior to applying heat and/or pressure the method further comprises: arranging a second panel of self-reinforced polymer on top of the first panel of self- reinforced polymer; and wherein applying heat and/or pressure further comprises simultaneously applying heat and/or pressure to at least one area on the surface of the second panel of self- reinforced polymer, the at least one area on the surface of the second panel of self- reinforced polymer being aligned with the at least one area on the surface of the panel of self-reinforced polymer, the application of heat and/or pressure simultaneously heating on the at least one portion of the first panel at the at least one area and at least one portion of the second panel at the at least one area to a temperature above or equal to the respective melting point of the at least one portions of the first and the second panel. In other words, the second panel and the first panel are arranged in layers on top of each other. Heat and/or pressure is then applied to the at least one area in the second panel and the first panel, simultaneously. The at least one area in each panel are positioned on each other, or aligned, in the stack of the first and second panels, for instance being the regions compressed between the jaws of a press. Typically, the at least one portion on the first and second panel will be of the same type of material, and so once heated above or to its melting point, will flow together and bond the first and second panel at this region.

Preferably, causing the at least one portion of the panel to cool to a temperature below the melting point comprises causing the at least one portion of the first panel and the at least one portion of the second panel to cool to a temperature below their respective melting point.

Preferably, after causing the at least one portions of the first and second panel to cool, the method further comprises: fixing a first planar component between the first and the second panel of self- reinforced polymer on a first side of the at least one area; fixing a second planar component between the first and the second panel of self- reinforced polymer on a second side of the at least one area, such that the at least one area is arranged between the first and the second planar component. In other words, the hinge formed in the first and second panel of self-reinforced polymer is used to hingedly join a first planar component and a second planar component. Said planar components may be the walls of a case or bag, for instance, and may themselves be a layered component.

Preferably, the first and the second planar component are each fixed by one of a group of fasteners comprising: gluing, stitching, riveting.

Preferably, the first and the second panel of self-reinforced polymer are each formed from a plurality of layers of self-reinforced polymer. Each layer of self-reinforced polymer may be formed as discussed above. For example, each panel of self-reinforced polymer may be formed from 2 to 10, or 2 to 8, or 2 to 6 layers of self-reinforced polymer. The layers may be compressed together under heat and pressure prior to a separate application of heat and pressure for forming the hinge. As such, the panel is formed of consolidated layers prior to use in the method described for formation of the hinge. As such, optionally, prior to applying heat and/or pressure, the plurality of layers of self- reinforced polymer of each of the first and/or the second panel are heated and compressed to consolidate the plurality of layers to form the respective first and second panel.

In an alternative, the layers of self-reinforced polymer making up the panel may be loosely arranged on each other (without being joined or consolidated prior to formation of a hinge). The act of applying pressure and heat as part of the method of forming of the hinge may further act to join the layers making up the panel of self-reinforced polymer. In some examples, pressure and heat may be applied across the whole panel (with extra pressure applied at the hinge pivot point) in order to consolidate the layers of self-reinforced polymer in the panel at the same time as forming of the hinge.

In a still further aspect, there is a hinge formed by the method of manufacture outlined above. For instance, any hinge in a self-reinforced polymer using the recited steps.

Brief description of the drawings

The disclosure may be put into practice in a number of ways, and preferred embodiments will now be described by way of example only and with reference to the accompanying drawings, in which: FIGURE 1 is a schematic representation of a first example of a hinge;

FIGURE 2 is a schematic representation of a second example of a hinge;

FIGURE 3 shows photographs of a hinge;

FIGURE 4 shows a photographs of a hinge incorporated into a bag or case;

FIGURE 5 shows examples of the fold made in a panel;

FIGURE 6 shows a schematic representation of a first example of the trim;

FIGURE 7 shows a photograph of the planar component and trim according to the first example;

FIGURE 8 shows a schematic representation of a second example of the trim;

FIGURE 9 is a schematic representation of a trim applied to a curved portion of a bag or case;

FIGURE 10 is a schematic representation of a first example of a reinforced or thickened planar component;

FIGURE 11 is a schematic representation of a second example of a reinforced or thickened planar component;

FIGURE 12 is a schematic representation of a further example of a hinge formed in a panel of self-reinforced polymer;

FIGURE 13 is a plan view of hinges formed according to the method described with reference to FIGURES 12, 14 and 15;

FIGURE 14 is a schematic representation of a still further example of a hinge formed in a panel of self-reinforced polymer;

FIGURE 15 is a schematic representation of a still further example of a hinge formed in a panel of self-reinforced polymer;

FIGURE 16 is a schematic representation of a yet further example of a hinge formed in a panel of self-reinforced polymer;

FIGURE 17 is a schematic representation of another example of a hinge formed in a panel of self-reinforced polymer;

FIGURE 18 is a schematic representation of an example of a hinge formed in a laminated panel comprising a layer of self-reinforced polymer;

FIGURE 19 is a schematic representation of another example of a hinge formed in a laminated panel comprising a layer of self-reinforced polymer;

FIGURE 20 is a schematic representation of a further example of a hinge formed in a laminated panel comprising a layer of self-reinforced polymer;

FIGURE 21 is a schematic representation of a still further example of a hinge formed in a laminated panel comprising a layer of self-reinforced polymer; and

FIGURE 22 shows photographs of walls of a case or cover joined using a hinge. In the drawings, like parts are denoted by like reference numerals. The drawings are not drawn to scale.

Detailed description of preferred embodiments

FIGURE 1 shows various views of a hinge according to a first example. FIGURE 1(a) shows a cross-section through the hinge, FIGURE 1(b) shows a plan view looking down (in the direction of arrow A) on the hinge shown in FIGURE 1(a), FIGURE 1(c) shows a view of a second panel portion forming part of the hinge, FIGURE 1(d) shows a plan view looking up (in the direction of arrow B) on the hinge shown in FIGURE 1(a), and FIGURE 1(e) shows a view of a first panel portion forming part of the hinge.

FIGURE 1(a) shows a first 10 and a second 12 planar component. The planar components are panels or side portions for a bag, case or box, to be joined by the described hinge. The panel may be formed of any material, but in a particular embodiment are a first and second planar component comprising at least one layer of self-reinforced polymer (such as self-reinforced polypropylene).

FIGURE 1(a) further shows a first panel 14 and a second panel 16. The first panel 14 is also shown in FIGURE 1(d) connected to the first 10 and the second 12 planar component. The first panel 14 is further shown in FIGURE 1(e), prior to connection to the first 10 and the second 12 planar component. The thickness of the first 14 and second 16 panel are typically less than, and often much less than, that of the first 10 and second 12 planar component.

The first panel 14 is divided into a first 18a and a second 18b section by a fold 20 extending across the first panel 14. The first section 18a is affixed or bonded to a first planar face of the first planar component 10. In the example shown, the fixture or bonding is by stitching 22a. The first section 18b is affixed or bonded to a first planar face of the second planar component 12. In the example shown, the fixture or bonding is by stitching 22b.

FIGURE 1(a) shows the second panel 16. The second panel 16 is also shown in FIGURE 1(b) connected to the first 10 and the second 12 planar component. The second panel 16 is further shown in FIGURE 1(c), prior to the connection to the first 10 and the second 12 planar component. The second panel 16 is divided into first 24a, second 24b, third 24c and fourth 24d section by three folds 26a, 26b, 26c extending across the second panel 16. The first 26a and third 26c fold bend in an opposite direction to the second fold 26b. The first section 24a of the second panel 16 is affixed or bonded to a second planar face of the first planar component 10. In the example shown, the fixture is by stitching 22a. The last section (which is the fourth section 24d in FIGURE 1) is affixed to a second planar face of the second planar component 12. In the example shown, the fixture is by stitching 22b. When the second panel 16 is affixed to the first 10 and second 12 planar component in this way, the second 24b and penultimate 24c (here, the third) section are folded towards each other, so as to almost face or abut an edge of each of the first 10 and second 12 planar component. In other words, the second 24b and third 24c sections are folded to almost face each other, and arranged to form an approximate T shape with the first 24a and final 24d section when the hinge is open. The second section 24b has a width, wi, that is substantially the same as the depth di of the edge of the first planar component 10. Similarly, the penultimate section (third section 24c) has a width that is substantially the same as the depth of the edge of the second planar component 12.

When the first 14 and second panel 16 are connected to the first 10 and second 12 planar component, a hinge is formed. The hinge allows for at least a full 180° range of movement between an ‘open’ configuration in which the first 10 and second 12 planar component are side-by-side, and a ‘closed’ configuration in which the first 10 and the second 12 planar components are arranged with the first planar face of the first planar component 10 opposing and parallel with the first planar face of the second planar component 12.

In the example shown in FIGURE 1, the hinge is further enhanced by stitching 28 of the first panel 14 to the second panel 16. The stitching 28 extends along the fold 20 of the first panel 14 and along the second fold 26b of the second panel. This stitching further binds the first 14 and second 16 panel and reinforces the hinge, increasing stiffness and robustness.

The hinge in FIGURE 1 comprises a self-reinforced polymer. In particular the first 14 and second 16 panel is formed of a portion of a layer or sheet of a self-reinforced polymer (such as self-reinforced polypropylene). Such material is hardwearing and strong, whilst still being lightweight. Moreover, the described hinge is robust and hardwearing, and provides a large range of movement despite the stiffness of the self-reinforced polymer material used.

The folds described can be formed in a number of ways, as discussed in more detail with reference to FIGURE 5, below. Fixture or bonding of the first 14 and second 16 panel to the first 10 and the second 12 planar component is show in FIGURE 1 as being via stitching, but can be implemented in various different ways. For example, the fixture may be by application of adhesive between surfaces, or by topical application of heat to the surfaces to be joined (which can cause melting and fusing when the materials solidify).

FIGURE 2 shows various views of a hinge according to a second example.

FIGURE 2(a) shows a cross-section through the hinge, FIGURE 2(b) shows a plan view looking down (in the direction of arrow A) on the hinge shown in FIGURE 2(a), FIGURE 2(c) shows a view of a second panel portion forming part of the hinge, FIGURE 2(d) shows a plan view looking up (in the direction of arrow B) on the hinge shown in FIGURE 2(a), and FIGURE 2(e) shows a view of a first panel portion forming part of the hinge.

FIGURE 2(a) shows a first 10 and a second 12 planar component. The planar components are panels or side portions for a bag, case or box, to be joined by the described hinge. The panel may be formed of any material, but in the particular example shown, the first and second planar component comprise a first and a second layer of self- reinforced polymer (such as self-reinforced polypropylene), with a foam layer between.

FIGURE 2(a) further shows a first panel 14 and a second panel 16. The first panel 14 is also shown in FIGURE 2(d) connected to the first 10 and the second 12 planar component with a view from above. The first panel 14 is further shown in FIGURE 2(e), prior to connection to the first 10 and the second 12 planar component. The first panel 14 is divided into a first 18a and a second 18b section by a fold 20 extending across the first panel 14. The first section 18a is affixed to a first planar face of the first planar component 10. In the example shown, the affixture is by stitching 22a. The first section 18b is affixed to a first planar face of the second planar component 12. In the example shown, the affixture is by stitching 22b.

FIGURE 2(a) shows the second panel 16. The second panel 16 is also shown in FIGURE 2(b) connected to the first 10 and the second 12 planar component and viewed from above. The second panel 16 is further shown in FIGURE 2(c), prior to the connection to the first 10 and the second 12 planar component. The second panel 16 is divided into five sections (a first 24a, second 24b, third 24c, fourth 24d and fifth 24e section) by four folds 26a, 26b, 26c, 26d extending across the second panel 16. The first 26a and fourth 26d fold are in an opposite direction to the second 26b and third 26c fold. The first and fourth fold are in the same direction.

The first section 24a is affixed to a second planar face of the first planar component 10. In the example shown, the fixing is by stitching 22a. The last section (fifth section 24e) is affixed to a second planar face of the second planar component 12. In the example shown, the fixing is by stitching 22b. When the second panel 16 is affixed or bonded to the first 10 and second 12 planar component in this way, the second 24b and penultimate 24d (here, the fourth) section are folded together, so as to face each other and to respectively abut an edge of each of the first 10 and second 12 planar component. The third section 24c forms the base of a trench, having the second 24b and fourth 24d sections as its walls.

The second section 24b has a width, W2, that is substantially the same as the depth d2 of the edge of the first planar component 10. Similarly, the penultimate section (fourth section 24d) has a width that is substantially the same as the depth of the edge of the second planar component 12.

When the first 14 and second panel 16 are connected to the first 10 and second 12 planar component, a hinge is formed. The hinge allows for at least a full 180° range of movement between an ‘open’ configuration in which the first 10 and second 12 planar component are side-by-side, and a ‘closed’ configuration in which the first 10 and the second 12 planar components are arranged parallel to each other, with the first planar face of the first planar component 10 opposing and parallel with the first planar face of the second planar component 12. Advantageously, this second example for the hinge, compared to the first example, may provide greater range of movement, beyond 180°, in view of the additional central section 24c and the additional fold. However, the high strength and superior robustness of the hinge remains.

In the example of FIGURE 2, the hinge is further enhanced by stitching 28 of the first panel 14 to the second panel 16. The stitching 28 extends along the fold 20 of the first panel 14 and through the third, central section 24c of the second panel. This stitching further binds the first 14 and second 16 panel and reinforces the hinge, increasing stiffness and robustness.

The hinge in FIGURE 2 comprises a self-reinforced polymer. In particular the first 14 and second 16 panel is formed of a portion of a layer or sheet of a self-reinforced polymer (such as self-reinforced polypropylene). Such material is hardwearing and strong, whilst still being lightweight. Moreover, the described hinge is robust and hardwearing, and provides a large range of movement despite the stiffness of the self-reinforced polymer material used.

The folds described can be formed in a number of ways, as discussed in more detail with reference to FIGURE 5, below. Fixing or bonding of the first 14 and second 16 panel to the first 10 and the second 12 planar component is show in FIGURES 1 and 2 as being via stitching, but can be implemented in various different ways as described below.

FIGURE 3 shows photographs of a hinge connecting a first and second planar component formed of a first and second layer of self-reinforced polypropylene with a layer of foam in between. The hinge shown in FIGURE 3(a), (c) and (d) are formed according the hinge of the first example, described above in relation to FIGURE 1. The hinge shown in FIGURE 3(b) is formed according the hinge of the second example, described above in relation to FIGURE 2. The first and second panel of the hinges shown in FIGURE 3 are each formed of a layer of self-reinforced polypropylene.

FIGURE 4 shows a hinge according to the first example described with reference to FIGURE 1, implemented within a collapsible bag. It can be seen that the hinge allows for the bag to be folded, despite the stiffness of the self-reinforced panels connected by the hinge. However, the hinge itself is robust and is not especially vulnerable to wear.

FIGURE 5 shows three options for forming a fold in the first or second panel, as required for implementation of the hinges described above in relation to FIGURES 1 and 2 and the trim described below in relation to FIGURES 6, 8 and 9. In the first example of FIGURE 5(a), the fold is formed by scoring the panel. Scoring the panel requires a cut that penetrates through only a portion of the panel (for example, through less than 50% of the thickness of the panel). The scoring creates a groove or scratch to be formed in the surface of the panel. The score 52 could be formed using a blade (such as a leather knife), or through laser, water jet or CNC cutting. The fold will then occur at the score, with the score forming the pivot for the fold. Generally the fold will be made in a direction such that the score is on the outside of the fold when the fold is closed.

In the example of FIGURE 5(b), small perforations 52 are made through the first or second panel. The perforations comprise small holes, spaced apart and arranged n a line across the panel. A fold is then made along the perforations 52. In this case, the fold may be made in either direction.

In the example of FIGURE 5(c), the fold is made by applying heat and pressure to a small linear region 54 of the first or second panel. In one example, a heated bar may be applied extending across the panel in the position of the fold. This causes melting and compression of this linear region. In this case, the fold may be made in either direction.

FIGURE 6 shows a first example of a trim for reinforcement of an edge of a planar component. The planar component may be a panel or wall of a bag box or case, for instance. FIGURE 6(a) shows a cross-section of the panel and trim. Here, the planar component 61 comprises a layer of self-reinforced polymer. The trim 66 is a section or binding, which wraps around the edge of the planar component in order to reinforce the edge. For instance, this may prevent wear at the edge of the component, or delamination of a layered planar component.

The trim comprises a panel 68 having two folds 70a, 70b which separate the panel into three sections 72a, 72b, 72c. The panel 68 is formed of a self-reinforced polymer, such as a layer of self-reinforced polypropylene. FIGURE 6(b) shows the panel 68 prior to affixture to the planar component. The folds 70a, 70b are created in the panel to be substantially parallel, and having a spacing, W ₃ , substantially equal to the depth or thickness, d ₃ , of the planar component.

Once folded, the panel 68 is folded around the planar component such that the folds of the panel align with the top and bottom edges of the planar component. A first section of the panel 72a is affixed or bonded to a first planar face of the planar component 61 , and a third section of the panel 72b is affixed or bonded to a second planar face of the planar component 61 (the second planar face opposing the first planar face). In the example of FIGURE 6(a), this fixing is by stitching 76 through the first section 72a of the panel, through the planar component, and through the third section 72c of the panel. However, alternative fixing methods could be used, as described elsewhere. The folds may be formed according to the methods described with reference to FIGURE 5, above.

Beneficially, the described trim 66 provides a strong and robust edging. This is especially useful for boxes, cases or packaging items, which are often dragged or scuffed during use. Furthermore, the trim provides a square or right-angled edge, that can be made accurately with minimum tolerances so that it sits flush to the planar surfaces of the planar component. This results in a finished product that can be stacked or folded together, with their edges closely aligned. Said trim may be particularly useful in collapsible boxes or packing cases, in which the sides may be stacked in a closed configuration.

FIGURE 7 is a photograph of a planar component comprising a first and second self-reinforced polypropylene layer with a foam layer between. A trim, as described with respect to FIGURE 6, is shown around the edge of the planar portion. It can be seen that the trim forms a precise, right-angled edge.

FIGURE 8 shows a second example of a trim for reinforcement of an edge of a planar component according to a second example. The planar component may be a panel or wall of a bag box, or case, for instance. FIGURE 8(a) shows a cross-section of the panel and trim. The trim of FIGURE 8 is similar to the trim of FIGURE 6, and corresponding features are described above with reference to FIGURE 6. However, the trim of FIGURE 8 additionally includes a further layer 160 arranged over the top of the planar component 64 and the first section 72a of the panel. The example of FIGURE 8 also includes a layer 162 arranged over the bottom of the planar component 64 and the second section 72c of the panel. The stitching for fixing of the trim to the planar component also acts to bond the two further layers 160, 162. In particular, the stitching is through the further layer 160, through the first section 72a of the panel, through the planar component 61 , through the third section 72c of the panel and through the still further layer 162. However, alternative fixing methods could be used, as described elsewhere. Just as in the example of FIGURE 6, the trim of FIGURE 8 provides a robust reinforcement for the edge of the planar component. It also provides a precise, well- defined edge, useful for stacking the planar components.

FIGURE 9 shows a curved section, edged with a trim. The trim may be substantially the same as the trim 66 discussed above with respect to FIGURE 6 or FIGURE 8. The panel 68 of the trim (prior to attachment to the planar component 61 is shown in FIGURE 9(c). Here, the two folds 70a, 70b, separate the panel 68 forming the trim into three sections 72a, 72b, 72c, just as before in the examples of FIGURES 6 and 8. However, in this example the first 72a and the third 72c section are themselves separated into tabs 80a-80h by removal of notches or angular sections 82a-82f.

Removal of angular sections 82a-82f to form tabs 80a-80h allows for the trim 66 to be arranged around a curved edge of a planar component 61. An example of such a planar component 61 is shown in FIGURE 9(b) having a curved edge that sweeps an arc around a 90° angle. In this case, the second section 72b of the panel may be arranged to abut an edge face of the planar component 61 , and the tabs 80a-80h forming part of the first 72a and third 72c section of the panel 68 can be fixed or bonded to the top and bottom planar surface of the planar component 61 (just as in the trim of FIGURE 6 or 8). Fixture may be according to any of the previously described methods, including stitching, adhesive or heat fusion. The trim applied to the planar component is shown in FIGURE 9(a).

An angle, Q, of the angular section 72a, 72b, 72c removed from the first 72a and third 72c section of the panel 68 is related to the angle, a, of the arc or curved edge of the planar component 61 as well as the number of cut outs and tabs 80a-80h. Preferably, the angle, Q, for the angular sections 82a-82f removed from the first 72a and third 72b section of the panel 68 will be calculated so that, when the panel 68 is applied to the planar component 61 as a trim, the angular ‘cut outs’ for each of the first 72a and third 72b sections are closed (but do not overlap), in order to maximise the protection afforded by the trim 66. In any case, the trim 66 will protect the edge face of the planar component 61 from wear and tear. It will be understood that the angular sections cut from a panel may not all have the same angle, Q, particularly if the arc or curved edge of the planar component comprises two or more curves of different arc or direction.

FIGURE 10 shows an example of a reinforced or thickened planar component. FIGURE 10(a) shows cross-section through such a planar component, and FIGURE 10(b) shows a plan view of said planar component.

In this example, the majority of the planar component comprises three foam layers 90a, 90b, 90c, and four self-reinforced polymer layers 92a, 92b, 92c, 92d, with a cover layer 96. However, the thickness of the planar component is graduated towards the edges, by ‘stepping’ the layers. Advantageously, this allows for the fixture or stitching to be made through only a single layer of foam 90a, and two layers of self-reinforced polymer 92a, 92b, each time. In this way, it is possible to build up the layers towards the centre of the planar component. However it may also make manufacture more straightforward, as the thickness of the material can fit more easily within standard stitching or manufacturing machines (and so the ‘foot’ of the sewing machine may not need to be raised compared to a typical manufacturing process).

The cover layer 96 is arranged over the graduated layers of the foam and self- reinforced polymer. The cover layer 96 may be formed of a self-reinforced polymer layer. The cover layer may provide protection to the stepped edges of the graduated layers. It may also improve the appearance of the planar component.

A trim 98, such as that discussed above with reference to FIGURE 6 and 7, is arranged around the outmost edge of the panel, including fastening the cover layer and the bottommost layers of foam and self-reinforced polymer.

FIGURE 11 provides an alternative example, having a reinforcing panel 190a that acts to stiffen a particular section of a planar component. FIGURE 11(a) shows a cross- section through the reinforced area, and FIGURE 11(b) shows a plan view of the whole reinforced planar component.

In this example, the reinforcement panel is a layer of foam 190a, arranged on a small area of another larger layer of foam 190b. The two foam layers 190a, 190b are sandwiched between a lower layer of self-reinforced polymer 193 and a cover layer of self- reinforced polymer 196. The edge is reinforced by a trim 198, which is affixed to the reinforced section using stitching 194. The two foam layers may be bonded to each other by use of an adhesive.

The reinforced regions provide additional stiffness and rigidity to the planar component, whilst minimising the weight of the planar component. The reinforcing panel 190a could also be positioned in regions in which additional wear is expected (such as a scuff plate), or in which additional protection is required to an item within a packaging case made of a number of the planar components. In some examples, the reinforcing panel 190a could comprise a portion of self-reinforced polymer, rather than the portion of foam as described with respect to FIGURE 11.

An alternative method for forming a hinge is described. FIGURE 12 shows various steps in the method of manufacture of a hinge. The method may be particularly suitable for manufacture of a hinge in a self-reinforced polymer material (or self-reinforced polymer composite, or self-reinforced polyolefin material). The below described methods may be used for forming the folds, as comprised within the hinge or trim described above in respect of FIGURES 1 to 11.

In a first step (see FIGURE 12(a)), a panel, sheet or planar portion 200 of a self- reinforced polymer material may be provided, in which it is desired to form a hinge. The panel of a self-reinforced polymer material 200 is placed on the first portion 204 of a press (such as a metal press).

In a second step, a second portion of a press 205 (such as a metal press) is placed on the surface of the panel 200 of the self-reinforced polymer material (as illustrated in FIGURE 12(b)). The second portion of the press 205 is placed in the position at which the pivot of the hinge is desired. The panel is then compressed between the first portion of the press 204 and a second portion of the press 205.

The first 204 and/or second 205 portions of the press are heated prior to coming into contact with the panel. During the compression step, heat transfers from the first 204 and/or second 205 portions of the press to the panel. This causes an area of the panel in contact with the press to increase in temperature At least a portion of the panel at the area is heated to a temperature at or above its melting point. In particular, the portion comprises the polymer material surrounding the fibres at the at least one area of the panel. This polymer material is heated above or to its melting point, such that the polymer surrounding the reinforcing fibres of the self-reinforced polymer melts and can flow. It will be understood that this could be the polymer matrix encasing the fibres, or the low-melting temperature grade polymer of the same type as the fibre, but which coats the outer surface of each fibre. The melting point is the temperature at which the material changes state from solid to liquid. As the melting point is less for the polymer material surrounding the fibres, ideally heat will be applied until a temperature is reached that is higher than or equal to the melting point of the polymer material surrounding the fibres but less than the melting point of the reinforcing polymer fibres themselves. As such, only the polymer material surrounding the fibres is melted.

Here, the press is shown having a first portion 204 which is a plate having a bulge 203 or convex patterning on its surface. The bulge 203 corresponds with the rod or bar forming the second portion 205 of the press. In this example, the first 204 and second 205 portion includes active heating elements, to maintain the temperature of the first and the second portion of the press for a period of time required to sufficiently heat the panel 200. However, in other examples, only one of the first 204 or second 205 portion may be actively heated, or the portions may be heated prior to contacting the panel 200 by contact with an external heat source. In the present example in which portions of the press are actively heated, the heating elements within the portions of the press are deactivated and allowed to cool after elapse of a predetermined time. The panel is retained in the press, and remains under compression whilst the panel (and press) is allowed to cool by transfer of the heat to the surroundings. Once the panel is cooled to a temperature below the melting point of the polymer material surrounding the fibres at the at least one area of the panel, this material solidifies.

In a third step, once cooled, the panel is removed from the press. The heated and/or compressed portion 210 is solidified (as shown in FIGURE 12(c)) and takes the shape defined by the pattern of the first 204 and second 205 portions of the press. The cooled, solidified area(s) 210 may have slightly different properties than the rest of the material, and offer a point at which a fold (or hinge) in the panel of the self-reinforced polymer material can pivot around.

FIGURE 13 shows plan views of two different panels 200, 202 of the self-reinforced polymer, in which a hinge has been formed. FIGURE 13(a) shows a panel 200 of the self- reinforced polymer having a linear region 212 that was heated and/or compressed, the linear region 212 extending across the sheet. FIGURE 13(b) shows a panel 200 of the self-reinforced polymer having a linear series of rectangular areas 214 that were heated and/or compressed. It will be understood that a linear series of heated and/or compressed areas of other shapes (circles, square, triangles, hexagons, etc.) could also be used. The shape and arrangement of the heated and/or compressed areas 212, 214 is prescribed by the particular shape or pattern of the first 204 and second 205 portion of the press used to heat and/or compress the areas of the panel 200 of the self-reinforced polymer.

In both FIGURE 13(a) and 13(b) the linear extending regions that have been heated and/or compressed 212, 214, and then allowed to cool, create a pivot point for a hinge or fold in the panel 200 of the self-reinforced polymer.

FIGURE 14 shows a number of steps for forming a hinge in a self-reinforced polymer material according to a further example. In a first step (FIGURE 14(a)), a first panel 200 of self-reinforced polymer is arranged on top of a second panel 220 of self- reinforced polymer. The panels 200, 220 are arranged loosely, and not glued, fastened or fused into place at this stage. Both the first and second panel are arranged on a first portion 204 of a press.

Again, each of the panels comprises fibres of polymer material, surrounded by the same type of polymer material but having a lower melting point than the polymer fibres.

The surrounding material may provide a polymer matrix encasing the polymer fibres to create a panel, or may be a polymer coating around each polymer fibre of a woven fabric of the coated fibres.

In a second step (FIGURE 14(b)), a second portion 205 of the press, here being a heated bar or stamp, makes contact with the uppermost, first panel 200 of self-reinforced polymer. Sufficient pressure is applied between the first 204 and second 205 portions of the press to ensure that the first panel 200 of self-reinforced polymer makes direct contact with the second panel 220 of self-reinforced polymer, so that the two sheets are compressed together. Moreover, heat is transferred from the first 204 and/or second 205 portions of the press to both the first 200 and the second 220 panel of self-reinforced polymer. The combination of heat and pressure cause the polymer material surrounding the polymer fibres at the regions in both of the first 200 and the second 220 panel in the vicinity of the first 204 and the second 205 portion of the press to exceed or equal the respective melting temperature of said surrounding material. The heating step is precisely executed to avoid the regions of the first and second panel from also exceeding the temperature of the melting point of the polymer fibres, which is higher than the melting point of the surrounding material. As such, the surrounding material, but not the fibres, are melted upon application of heat and pressure. Once melted, the surrounding material at each of the first and the second panel can flow and mix.

The panels are subsequently allowed to cool. Cooling may take place whilst remaining in the press, such that the compression is maintained during cooling. The portions of the panel are cooled to a temperature less than the melting point of the polymer material surrounding the polymer fibres, such that the heated portions of the panel solidify.

As shown in FIGURE 14(c), the panels are subsequently removed from the press. The first 200 and second 220 panel of self-reinforced polymer are fused together at the points 215 where the heat and/or pressure was applied. The fused portions 215 provide the pivot of the hinge, whilst also acting as a join between the first 200 and second 220 panel of self-reinforced polymer.

A final, optional step (shown in FIGURE 14(d)) is to introduce a first planar component 225 between the first 220 and second 220 panel of self-reinforced polymer on one side of the hinge (in other words, on one side of the previously heated and/or compressed region(s) 215). A second planar component 230 can be arranged between the first 200 and second 220 panel of self-reinforced polymer on the other side of the hinge (in other words, on the other side of the heated and/or compressed region(s) 215). The first 225 and second 230 planar components may be a foam sheet, a further sheet of self- reinforced polymer, or a layered panel including more than one material type. The planar components may comprise walls of a case or box, which are hingedly connected by the formed hinge.

The planar components 225, 230 can be fastened to the first 200 and second 200 panel of self-reinforced polymer using a fastener. In the case of FIGURE 14(d) the fastener is stitching 235, although other types of fastener (for instance, riveting or gluing) could be envisaged. In an alternative, the planar components 225, 230 could be left loose between the first 200 and second 220 panel of self-reinforced polymer, for example enclosed in a pocket generated by hinges (heated areas 215) applied around the perimeter of the planar component(s) 225, 230, but without any direct fastening between the planar component(s) 225, 230 and the first 200 and second 220 panel of self-reinforced polymer.

It will be understood by the skilled person that the wings of the panels 200, 220 of self-reinforced polymer (being either side of the hinge 215) in FIGURE 12(c) could be connected, joined or fastened to planar panels. Conversely, although the hinge in FIGURE 14(d) is shown as having planar components 225, 230 applied, this is not essential, and the first 200 and second 220 panel of self-reinforced polymer (joined at the hinge 215) could be used alone.

It will be understood that the method of forming a hinge (especially described with reference to FIGURE 14) could be used to affix or bond the first panel 14 and the second panel 16 in place of the stitching 28 shown in at FIGURE 1 or FIGURE 2.

FIGURE 15 shows a number of steps for forming a hinge in a self-reinforced polymer material according to a still further example. The example hinge is formed in a section of material having a planar element 250 (such as a foam portion or foam panel), and a panel of self-reinforced polymer 200.

In a first step (FIGURE 15(a)), a planar portion 250 is arranged on a panel 200 of self-reinforced polymer. The planar portion is a layer of polymer foam (such as expanded polypropylene, for instance). The panel 200 and planar portion 250 may be arranged loosely, and not glued or fastened into place at this stage. Alternatively, the panel 200 and planar portion 250 may be glued or heat fused together. All the elements are arranged on a first portion 204 of a press.

In a second step (FIGURE 15(b)), a second portion 205 of the press, here being a heated bar or stamp, makes contact with the uppermost face of the planar element 250. Sufficient pressure is applied between the first 204 and second 205 portions of the press to ensure that the planar portion 250 and the panel 200 of self-reinforced polymer are compressed together (at least in the region between the first 204 and second 205 portion of the press). Moreover, heat is transferred from the first 204 and/or second 205 portions of the press to both the panel 200 of self-reinforced polymer, and the planar portion 250. The combination of heat and pressure cause the polymer material surrounding the polymer fibres at the heated and compressed regions of the panel 200 of self-reinforced polymer, as well as the heated and compressed regions of the planar element 250, to exceed or equal their respective melting temperature (and so melt).

The panel and planar portion may be allowed to cool in the press. The heat may be allowed to transfer from the panel, planar portion and first and second portions of the press to the surroundings (or to atmosphere). This causes the previously melted portions to solidify, and their temperature is reduced to below their respective melting point.

As shown in FIGURE 15(c), the panel 200 and planar portion 250 are then removed from the press. The panel of self-reinforced polymer 200, and the planar portion 250 are fused together at the points 215 where the heat and/or pressure was applied. Once cooled, the fused portions 215 provide the pivot of the hinge, whilst also acting as a join for the panel 200 with the planar portion 250.

It will be understood that compression and heating as described results in the hinge having less overall thickness than the surrounding areas of the panel and the planar element. The press can be used to create a pattern in a large section of layered material, from which a net (for example, for a box or case), including various hinges, can be cut. Moreover, a specific shape for the hinge (for instance, representing a different ‘v-shaped’ groove with a different angle of opening) can be formed according to a specific choice of the shape and pattern of the jaws of the press used to create the hinge. Magnified examples of different types of formed hinge can be seen in FIGURE 15(d) and 15(e).

FIGURE 16 shows a number of steps for forming a hinge in a self-reinforced polymer material according to a still further example. In a first step (FIGURE 16(a)), a first panel 200 self-reinforced polymer is arranged on top of a planar portion 250, which is itself on a second panel 220 of self-reinforced polymer. The planar portion is a layer of polymer foam (such as expanded polypropylene, for instance). The panels 200, 220 and planar portion 250 are arranged loosely, and not glued or fastened into place at this stage. All the elements are arranged on a first portion 204 of a press.

In a second step (FIGURE 16(b)), a second portion 205 of the press, here being a heated bar or stamp, makes contact with the uppermost, first panel 200 of self-reinforced polymer. Sufficient pressure is applied between the first 204 and second 205 portions of the press to ensure that the first panel 200 of self-reinforced polymer, the planar portion 250, and the second panel 220 of self-reinforced polymer are compressed together. Moreover, heat is transferred from the first 204 and/or second 205 portions of the press to both the first 200 and the second 220 panel of self-reinforced polymer, and the planar portion 250, in the vicinity of the first and second portions of the press. The combination of heat and pressure cause the polymer material surrounding the polymer fibres at each panel 200, 220 in the vicinity of the first 204 and second 205 portion of the press, and the planar element 250 in the vicinity of the first 204 and second 205 portion of the press, to exceed or equal their respective melting temperature.

The panels 200, 220 and planar portion 250 are then allowed (or caused) to cool, and any melted portions solidify. As shown in FIGURE 16(c), the panels 200, 220 and planar portion 250 are removed from the press. The first panel of self-reinforced polymer 200, the planar portion 250, and the second panel of self-reinforced polymer 220 are fused together at the points 215 where the heat and/or pressure was applied. Once cooled, the fused portions 215 provide the pivot of the hinge, whilst also acting as a join for the first 200 and second 220 panels, with the planar portion 250 sandwiched in-between.

A number of combinations of the various described embodiments could be envisaged by the skilled person. All of the features disclosed herein may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive. In particular, the preferred features of the invention are applicable to all aspects of the invention and may be used in any combination. Likewise, features described in non-essential combinations may be used separately (not in combination).

It will be understood that the panels of self-reinforced polymer 200 (which could also be described as panels of self-reinforced thermoplastic composite) can be formed of a plurality of layers of the self-reinforced polymer material. In particular, a single layer may be formed from stretched strands or extruded fibres of the polymer material. Said strands are then formed into a layer, either by heating and compression of aligned strands (which causes the outermost surface of each strand to melt and flow, in order to form a polymer matrix surrounding the strands), or by weaving a fabric of the fibres of polymer material which are themselves coated in a lower-melt temperature grade of the same polymer (and which, optionally, could then be heated and compressed to generate a polymer matrix).

The described layers may be built up (laminated) to create a panel of a desired thickness. The panel may comprise one or more layers. In some examples, the panel will comprise 1 to 10, or 2 to 10 layers. In order to consolidate the layers of a panel, the layers are typically compressed and heated such that the polymer material surrounding the polymer fibres (either the polymer matrix or the polymer coating surrounding the fibres) melts, flows and consolidates with the corresponding material in other layers. Thus, upon cooling the panel is formed of a plurality of consolidated layers. A larger number of consolidated layers increases the thickness of the panel. This in turn changes the properties of the panel, from being flexible (for instance, in a panel with 1 to 8 or 2 to 8 layers) to being rigid (for instance, in a panel having 15 or more layers). In the present example, the hinges may be formed using a panel already formed in this way. For instance, the panel described in relation to FIGURE 16 may be formed having multiple consolidated layers, joined prior to any step of application of heat or pressure used to form the hinge. However, as an alternative, the consolidation of the layers may take place in the same processing step as the application of heat and pressure for forming the hinge. This is shown in FIGURE 17.

Referring to FIGURE 17(a), a first 221 and a second 222 layer of the second panel 220 of the self-reinforced polymer is arranged on a first portion of the press. The layers are loose, and at this stage are not consolidated. The layers may each be a woven layer of polymer fibres, each fibre coated in a lower melting point grade of the same polymer.

A planar element 250 is arranged on the first 221 and the second 222 layer of the second panel 220. A first 201 and second 202 layer of the first panel 200 is then arranged on top of the planar element 250. Once again, the layers may each be a woven layer of polymer fibres, each fibre coated in a lower melting point grade of the same polymer.

Again, this first 201 and second 202 layer of the first panel 200 are loose, and not consolidated at this stage.

As shown in FIGURE 17(b), the second portion of the press 205 is then applied, so that the layers are between the first 204 and second 205 portions of the press, which are heated. In this example, the second portion 205 of the press is a plate having a patterned surface including concave and convex portions. The first 204 and second 205 portions of the press are bought together, to compress the layers in between. The heated portions of the press also transfer heat to each element. In particular, at least a portion of the coating surrounding each polymer fibre at each of the first 201 , 221 and second 202, 222 layer of the first 200 and second 220 panel is heated above or equal to its melting point. Furthermore, at least the surfaces of the planar element 250 are heated above or equal to its melting point. This causes the material at layers 201, 202, 221, 222 of the panels, as well as the planar element 250 to melt and flow. The greater region of compression as a result of the patterning of the first 204 and second 205 portions of the press create the hinge as previously described. Again, appropriate selection of the shape and pattern for the portions of the press may determine characteristics of the hinge.

The fused panels 200, 220 and planar element 250 may then be allowed to cool. Upon removal from the press, as shown in FIGURE 17(c), the first 200 and second 220 panel are each formed of the first and second consolidated layers, whilst also being fused with the planar element 250 in between. The more compressed region forms a hinge in the layered structure. As will be understood, although FIGURE 17 shows a panel 200, 220 comprising only a first and a second layer, any number of layers could be used. The plurality of layers within the panel could comprise 2 to 15, 2 to 20, 2 to 10, 2 to 8 or 2 to 6 layers. More layers could also be used (for instance 12 to 20 layers, for a thicker panel). Alternatively, the panel does not necessarily require a plurality of layers, and instead just a single layer of self-reinforced polymer could be used.

Moreover, in the example described at FIGURE 17 in which the layers of the self- reinforced polymer are thermo-compressed (heated and compressed) and fused at the same time as formation of the hinge, two panels of self-reinforced polymer are used together with a planar element. It will be understood that this is not necessarily the case, and the examples shown in FIGURES 12 to 16 using a consolidated panel could equally be formed using previously unconsolidated layers of self-reinforced polymer material by use of any appropriate choice of shape and patterning for the first and second portion of the press.

It will be understood that, although in the examples of FIGURES 14, 16 and 17 the first panel is arranged on top of the second panel, the second panel could equally be arranged on top of the first panel. The notation of the panels as ‘first’ and ‘second’ is arbitrary, and used for clarity of description only.

As an alternative to a heated press, sonic (ultrasonic) welding can be used as a method to heat and thereby partially melt portions of the self-reinforced polymer panels (or layers of the panels). This mechanism can be used to fuse together layers of the panels, to fuse together panels with other planar components, or to form the hinge by applying heat and/or pressure, as described above. Fabrics of certain different polymers may be bonded together by this process, including fabric based polymers such as polypropylene (PP), polyethylene terephthalate (PET), etc. Such sonic welding techniques may provide a controllable and precise mechanism for forming a pivot of the hinge, as described above.

In particular, ultrasonic plastic welding is the joining or reforming of thermoplastics (or polymers) through the use of heat generated from high-frequency mechanical motion. High-frequency electrical energy is converted into high-frequency mechanical motion, which along with applied force, can create frictional heat at the surface of the polymer causing the material to melt. When the melted portion solidifies, molecular bonds are made, which may be between material at different layers of a stacked structure, for instance. Thus, the different layers are joined or fused. This method can also be used to form the hinge as discussed above, or for precision cutting of self-reinforced polymer material. A still further method of forming the hinge is described. FIGURE 18 shows steps for an example method of forming a hinge in a laminated panel, wherein the laminated panel incorporates a layer of self-reinforced polymer 500 and a layer of foam 550. In a first stage (see FIGURE 18(a)), a laminated panel is provided, in which it is desired to form the hinge. In a second stage (see FIGURE 18(b)), a valley 540 is formed in a surface of the foam layer 550 of the laminated panel. In particular, a v-shaped cut-out forms the valley 540.

The valley may be cut using a blade 560. The deepest point of the valley provides the pivot for the hinge. Ideally, the deepest portion of the valley 540 does not cut through or penetrate into the layer of self-reinforced polymer 500. The depth of the valley may be 60% or more, or 75% or more, or even 100% of the thickness of the foam layer.

FIGURE 19 shows a further example for a hinge in a laminated panel. This laminated panel comprises a first 500 and a second 520 layer of self-reinforced polymer, with a foam layer 550 between. In a first step (see FIGURE 19(a)), the laminated panel is provided. In a second step (see FIGURE 19(b)), a valley 540 is formed in the laminated panel. Here, the valley 540 is formed to cut through the second layer 520 of self-reinforced polymer, with the valley 540 formed in the foam layer 550. Once again, the deepest point of the valley 540 provides the pivot of the hinge. The deepest portion of the valley 540 ideally does not cut through or penetrate into the first layer 500 of self-reinforced polymer.

FIGURE 20 shows a still further example for a hinge in a laminated panel. This laminated panel comprises a first 500 and a second 520 layer of self-reinforced polymer, with a foam layer 550 between. The first 500 and the second 520 layers of self-reinforced polymer each comprise a plurality of consolidated layers 501, 502, 521, 522 of self- reinforced polymer. Each of the first 500 and the second 520 layers of self-reinforced polymer may have a different number of consolidated layers of self-reinforced polymer, and in some examples only one of the first 500 and the second 520 layers of self-reinforced polymer may have a plurality of layers. The number of consolidated layers used in each of the first 500 and the second 520 layer of self-reinforced polymer may be 2 to 12, and more preferably 2 to 8 consolidated layers. The number of consolidated layers in each of the first 500 and the second 520 layer of self-reinforced polymer may be chosen to obtain a particular thickness for the given self-reinforced polymer layer. In the example of FIGURE 20, each of the first 500 and the second 520 layers of self-reinforced polymer comprise two consolidated layers 501, 502, 521, 522 of self-reinforced polymer.

In a first step (see FIGURE 20(a)), the laminated panel is provided. In a second step (see FIGURE 20(b)), a valley 540 is formed in the laminated panel. Here, the valley 540 is formed to cut through the second layer 520 of self-reinforced polymer, with the valley 540 formed in the foam layer 550. Once again, the deepest point of the valley 550 provides the pivot of the hinge. The deepest portion of the valley 540 does not cut through or penetrate into the first layer of self-reinforced polymer 500.

FIGURE 21 shows the hinge illustrated in FIGURE 20, but with an additional lining layer 570. The lining layer 570 covers the walls of the valley 540 formed in the laminated layer, and also extends across a surface of second self-reinforced polymer layer 520. The lining layer 570 may be nylon, or may be felt or another material. The lining layer 570 may be applied after formation of the valley 540.

In relation to the hinges described with respect to FIGURE 18, 19, 20 or 21, the valley 540 can be formed in various ways. For instance, the valley 540 may be cut into the laminated panel using a blade. In one example, the blade is part of a sliding guillotine. Alternatively, a laser could be used to form the valley 540. In a still further example, the valley 540 could be formed by incision with a hotwire. Use of a method of cutting that heats the walls of the valley 540 (for instance, use of a hot wire, or use of laser cutting) beneficially melts the material at the walls of the valley 540, and so seals those portions of the layers.

Beneficially, formation of the valley 540 creates a thinner region for the laminated panel at which the fold of the hinge will be formed. Ideally, the valley 540 is shaped so that the walls of the valley 540 formed as part of the hinge face each other (and likely make direct contact) when the hinge is in the folded position. In relation to the hinges described with respect to FIGURE 18, 19, 20 or 21, the valley 540 may have a different internal angle, b, between the intersecting planes forming the walls of the v-shaped valley. The internal angle, b, may be chosen according to the angle required for the hinge in its folded position. For instance, where the hinge is required to form a 90 degree corner between first 580 and second 585 portions of the laminated panel (where the first 580 and second 585 portion are separated by the hinge), then the internal angle, b, between the intersecting planes of the walls of the valley will be 90 degrees. Where the hinge is required to form a 120 degree corner between first 580 and second 585 portions of the laminated panel, then the internal angle, b, between the intersecting planes of the walls of the valley will be 60 degrees. Generally, an N degree corner between first 580 and second 585 portions of the laminated panel require an internal angle, b, between the intersecting planes of the walls of the valley of b =180 -N degrees.

In relation to the hinges described with respect to FIGURE 18, 19, 20 or 21, the self-reinforced layers 500, 520 may be any self-reinforced polyolefin, or any self-reinforced polymer composite. In an example, the self-reinforced polymer is self-reinforced polypropylene, or self-reinforced polyethylene. The foam 550 may be a microcellular polymer or expanded polymer foam. In an example, the foam 550 may be microcellular polypropylene, expanded polypropylene, or ethylene-vinyl acetate foam. The foam layer may be 2 mm to 20 mm thick, and more preferably 5 mm to 14 mm thick. The layers of the laminated panel are bonded together prior to formation of the valley described above.

FIGURE 22(a) shows an example of a hinge 600 formed according to FIGURE 21.

In particular, the hinge 600 is formed in a laminated layer comprising a first and second layer of self-reinforced polymer (each comprising two consolidated layers of self-reinforced polymer). An expanded polypropylene foam (10 mm thick) is arranged between the first and the second layer of self-reinforced polymer. The valley 640 is formed in the foam layer, by cutting through the second self-reinforced polymer layer. The whole of the valley 640 and the surface of the second polymer layer is covered with a lining layer.

FIGURE 22(b) shows a net for a box, and FIGURE 22(c) shows the same net in its three-dimensional configuration constructed as a box. The net and box of FIGURES 22(b) and 22(c) comprise hinges 700 as shown in FIGURE 20 between each face of the box. Here, the net is formed from a single laminated panel comprising a first and second layer of self-reinforced polymer (each comprising two consolidated layers of self-reinforced polymer), and an expanded polypropylene foam arranged between the first and the second layer of self-reinforced polymer.

A number of combinations of the various described embodiments could be envisaged by the skilled person. All of the features disclosed herein may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive. In particular, the preferred features of the invention are applicable to all aspects of the invention and may be used in any combination. Likewise, features described in non-essential combinations may be used separately (not in combination).

Each feature disclosed in this specification, unless stated otherwise, may be replaced by alternative features serving the same, equivalent or similar purpose. Thus, unless stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.

As used herein, including in the claims, unless the context indicates otherwise, singular forms of the terms herein are to be construed as including the plural form and, where the context allows, vice versa. For instance, unless the context indicates otherwise, a singular reference herein including in the claims, such as "a" or "an" means "one or more". Throughout the description and claims of this disclosure, the words "comprise", "including", "having" and "contain" and variations of the words, for example "comprising" and "comprises" or similar, mean that the described feature includes the additional features that follow, and are not intended to (and do not) exclude the presence of other components. The use of any and all examples, or exemplary language ("for instance", "such as", "for example" and like language) provided herein, is intended merely to better illustrate the disclosure and does not indicate a limitation on the scope of the disclosure unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the disclosure.

Any steps described in this specification may be performed in any order or simultaneously unless stated or the context requires otherwise. Moreover, where a step is described as being performed after a step, this does not preclude intervening steps being performed. A method of manufacturing disclosed herein is also provided. The method may comprise steps of providing each of the features disclosed and/or configuring or using the respective feature for its stated function.