Description:

The invention pertains to a material, in particular for use as a backing for floor coverings, a process for manufacturing such a material and a modular flooring comprising such a material.

Modular flooring is used in many applications such as laminate and carpet tiles as flooring in residential households and public buildings such as hotels, offices, hospital and shops. Also, modular flooring can be found in office buildings and public transports such a trains and aircrafts and ships such as cruises and ferries.

To be called modular flooring, the modular flooring must have a discrete size such that it can be carried easily and that the installation and deinstallation of such a modular flooring can be performed without lifting heavy rolls of flooring material.

In the prior art several composites are known, which can be used as modular flooring such as “click-laminate”. A kind of click laminate is disclosed by EP 2422 027 B1.

US 8,061 ,929 B2 discloses a rig mat comprising rectangular panels fastened end to end by cooperating connectors, which are attached separately to the panels.

WO 93/23638 discloses a portable dancefloor comprising a plurality of assemble square sections and a sloping perimeter around the dance floor, wherein the parts comprise cooperating magnetic attraction means.

WO 2019/137966 A1 discloses a carpet tile comprising a base, preferably a primary carpet base having pile yarns projecting upwardly therefrom, and a backing structure attached to a lower side of said base. The carpet tile may comprise opposite tile edges provided with a pair of complementary coupling parts allowing a plurality of such tiles to be connected.

WO 2018/206554 A1 discloses a method for connecting a nonwoven carrier material comprising a first part having a thickness and a second part having a thickness, wherein the first part and the second part comprise at least a first and a second thermoplastic fiber layer, wherein part of the thickness of the first part and part of the thickness of second part is removed to form the first thermoplastic fiber layer and the second thermoplastic fiber layer in such a way that the first part and the second part form together a form-fit connection in the connecting area.

JP 2012139931 A discloses a honeycomb panel of a sandwich structure, the honeycomb panel being formed by combining a plurality of honeycomb pieces, each piece comprising join part in the outer circumference. The individual honeycomb pieces are formed by injection molding, and the join parts are integrally injection molded.

However, most of the floorings of the prior art comprise form-fit connections, which are separate parts added to the flooring, such that additional working steps are necessary to provide such floorings. The floorings of the prior art also comprise wood and/or metal such that the floorings are quite heavy.

Further, by using such flooring additionally sound insulating materials have to be applied if used in house, automotive or public transport. Such an additional sound insulation material is disclosed in the unpublished Patent Application EP 19189072.2.

The object underlying the present invention is to provide a material, in particular for use as a backing for floor coverings and a modular flooring, which can be provided easily with reduced working steps, is lightweight and has at the same time an improved dimensional stability. Further, a modular flooring has to be provided comprising the advantageous properties of the material and excellent sound insulating properties, whereby the modular flooring is more suitable for recycling.

The object of the present application is solved by a material, in particular for use as a backing for floor coverings, comprising at least a folded core structure, a first part of a form-fit connection on at least one edge of the material and a second part of a form-fit connection on at least one edge of the material, wherein the folded core structure comprises a synthetic polymer, characterized in that the first part and the second part of a form-fit connection comprise at least deformed synthetic polymer originating from the folded core structure.

A flooring composite is understood to mean a floor covering or a flooring comprising a base layer and a cover layer.

Within the scope of the invention, the term “form-fit connection” has to be understood as a mechanical connection between two materials, which shall be connected. Thereby, the form-fit connection is provided by a first part of a form-fit connection and a second part of a form-fit connection, which fit together by the key and lock principle. The first part of the form-fit connection and the second part of the form-fit connection are typically located on different materials, which shall be connected. Thus, the first part of a form-fit connection on a first material can be connected with a second part of a form-fit connection on a second material to perform the form-fit connection of these materials. It is also possible that a first material comprises more than one first part of a form-fit connection such that more than two materials can be connect. Further, a material can comprise a first part of a form-fit connection and a second part of a form-fit connection. Thereby, it is possible that a first material comprising at least a first part of a form-fit connection on one edge and at least a second part on another edge, the first material can be connected by the first part of a form-fit connection to a second material comprising at least a second part of a form-fit connection, and the first material can be connected by the second part of a form-fit connection to a third material comprising at least a first part of a form-fit connection. It is also possible to provide a number of form-fit connection to the first material by further materials, which corresponds to the number of first parts of form-fit connections and second parts of form-fit connections provided at the first material. Preferably, the first part of the form-fit connection and the second part of a form-fit connection are designed such that the first part of a form-fit connection and the second part of the form-fit connection can be easily put together (installation) and also easily taking apart (deinstallation). But, the first part of a form-fit connection and the second part of a form-fit connection exhibit a strong connection if installed to a form-fit connection, thus, the materials connected by the form-fit connection have an excellent dimensional stability such as bending stiffness, shear strength and such material prevents or at least reduced dishing and doming of floor covering, which can be attached to the material. Further, modular flooring comprising materials comprising a first part of a form-fit connection and/or a second part of a form-fit connection have the advantage that the modular flooring has an improved stability in terms of locality. This means that the modular flooring does not move away from other modular floorings due to the provided form-connection. Further, using such modular flooring makes it possible to personalize the modular flooring in terms of e.g. color, patterns and different combinations thereof, for example in carpets of limited dimensions under a coffee table. An example is a traffic carpet for children, comprising such a modular flooring. Thereby, it is possible to provide modular flooring having different motives of traffic carpets, which can be combined personally. Another example is modular flooring for an exhibition booth, which would no longer require framing members to keep the modular flooring parts together when the modular flooring parts comprise materials comprising a first part of a form-fit connection and/or a second part of a form-fit connection.

Without being bound to theory, it is believed that due to the fact that the first part and the second part of a form-fit connection comprise at least deformed synthetic polymer originating from the folded core structure, the folded core structure is intimately connected with the first part of a form-fit connection and the second part of a form-fit connection, thus, the dimensional stability of a connection between two materials provided by the form-fit connection of a first part of a form-fit connection and a second part of a form-fit connection is improved. Thereby, the term “intimately connected” has to be understood that the folded core structure and the first part of a form-fit connection and the second part of a form-fit connection are provided from the same uncut flat body such that no additional bonding agent or bonding technique is required. Thus, the folded core structure and the first part of a form-fit connection and the second part of a form-fit connection is one pieced. Further, as the first part of a form-fit connection and the second part of a form-fit connection comprise at least deformed synthetic polymer originating from the folded core structure, less working steps by the manufacturing of the material are necessary, thus, the manufacturing of the material can be simplified. As the manufacturing process of the material can be simplified by less working steps, the manufacturing of the material is less cost intensive.

Preferably, the first part of a form-fit connection on at least one edge of the material and the second part of a form-fit connection on at least one edge of the material have a density which is higher than the density of the non-deformed folded core structure.

Preferably, said folded core structure is a folded core structure being produced from an uncut flat body which can be composed of a synthetic polymer, by plastic deformation perpendicular to the plane of the material such that three-dimensional structures and connection areas are formed, so that half cells and connection areas are formed, wherein the half cells are at an angle a to each other to provide a relaxed honeycomb structure or adjoin one another in the form of a honeycomb cell to provide a half-closed folded honeycomb structure. The connection areas are relatively small in comparison to the half cells. The uncut flat body preferably is a continuous film. In another embodiment, the folded core structure may have been folded into a regular three-dimensional structure with a multiplicity of folds along differently oriented folding lines and with elevations and depressions along folding lines, using shaping dies as is for example disclosed by WO 2015149954 A1. The folding lines may for example be described by zigzag patterns of consecutive straight segments, but may also be described by consecutive curved segments or a continuous corrugated profile.

In a preferred embodiment, the folded core structure is water impermeable and the void volumes on one side of the layer of the folded core structure are not connected to void volumes on the other side of the folded core structure.

The folded core structure can be a half-closed honeycomb structure, such as for example disclosed by WO 2006/053407 A1. This half-closed honeycomb structure can be provided from an uncut flat body, which can be composed of a thermoplastic polymer or thermoplastic elastomeric polymer, by plastic deformation perpendicular to the plane of the material such that three-dimensional (3D) structures and connection areas are formed, i.e. half-cell walls and connection areas are formed (Fig. 3). The connection areas are relatively small in comparison to the half cells. Subsequently, the 3D-structures are pushed towards each other at predefined folding lines to form cells having cell walls adjoining one another in the form of a honeycomb cell. Thereby, the term “adjoining” means that the cell walls are in contact to each other, but the most of the adjoining cell walls are free of bonding. Solely at one edge of the cell walls, the adjoining cell walls are connected to each other. The one edge of the cell walls is located in a first main surface of the folded core structure or in a second main surface of the folded core structure. A folded core structure being produced from an uncut flat body which can be composed of a synthetic polymer, by plastic deformation perpendicular to the plane of the material such that three-dimensional structures and connection areas are formed, so that half cells and connection areas are formed, wherein the half cells are at an angle a to each other to provide a relaxed honeycomb structure would provide a reduced contact area between the folded core structure over a folded core structure folded into a regular three-dimensional structure with a multiplicity of folds along differently oriented folding lines and with elevations and depressions along folding lines, using shaping dies, which is believed to be beneficial for acoustic impact sound insulation.

Thereby, the first main surface is established by parts of the folded core structure, which are extending the most above the plane of the x- and y- direction, and the second main surface is established by parts of the uncut flat body, which are extending the most below the plane of the x- and y-direction.

Within the scope of the invention, the uncut flat body has to be understood as a thin body, which is a one pieced body, i.e. which does not consist of multiple parts connected to each other to provide the extension of the uncut flat body in x- and y- direction. This means the uncut flat body consists of solely one body and is free of any connections, e.g. seams, glued portions or welded portions. Further, the term “provided from an uncut flat body” is understood to mean that the flat body is not cut to enable folding of the deformed sheet into a core having a three-dimensional structure. The uncut flat body may however be cut to provide a certain width and/or length of the uncut flat body before the uncut flat body is plastically deformed. It is therefore to be understood that the core having a three-dimensional structure is formed from an uncut flat body.

In a preferred embodiment, the honeycomb cells comprised in the half-closed honeycomb structure and in the relaxed honeycomb structure are polygonal cells with a number n of walls. The number n is at least 3 and goes in principle to infinite, which is circular. Preferably, the number n has an even value, more preferably n has the value of 4, 6 or 8, and most preferably n has the value of 6. In the case of the relaxed honeycomb structure, it has to be understood that the number n of walls of the honeycomb cells refers to the number of walls of two half cell walls which are at an angle a to one another. Preferably, the formed honeycomb cells are closed by the connection areas at one end of the honeycomb cell, such that the honeycomb structure is water and/or gas impermeable over its entire extension and the void volumes on one side of the folded core structure are not connected to void volumes on the other side of the folded core structure.

Alternatively, the formed honeycomb cells exhibit holes in the connection areas at one end or are open at both ends, such that the void volumes on one side of the folded core structure are connected with the void volumes of the other side of the folded core structure.

The folded core structure can also be a relaxed honeycomb structure. This relaxed honeycomb structure is produced in the same manner as the half-closed honeycomb structure with the exception that the folding of the plastically deformed uncut flat body is stopped before the half-cell walls meet together to form the half- closed honeycomb structure.

As the folding of the plastically deformed uncut flat body is stopped before the half cells meet together, or fully folded cell walls are reopened, the half-cells are at an angle a to each other.

In a preferred embodiment, the angle a in the relaxed honeycomb structure is of at most 110°, preferably of at most 100°, more preferably of at most 90° even more preferably of at most 85°, and most preferably of at most 80°.

In another preferred embodiment, the angle a in the relaxed honeycomb structure is of at least 1 °, preferably of at least 25°, more preferably of at least 45°, and most preferably of at least 60°. In a further preferred embodiment, the angle a in the relaxed honeycomb structure is up to 110°, preferably between 1° and 100°, more preferably between 25° and 90°, even more preferably between 45 and 85°, and most preferably between 60° and 80°.

Without being bound to theory, it is believed that an angle exceeding 110° will deteriorate the stability, e.g. the compression resistance, of the relaxed honeycomb structure, thus deteriorating the dimensional stability of the folded core structure, respectively of the flooring composite.

Due to the fact that the relaxed honeycomb structure is manufactured in the same manner as the half-closed folded honeycomb structure, the plastically deformed uncut flat body also comprises 3D-structures and connection areas such that the relaxed honeycomb structure can also be water impermeable and the void volumes on one side of the folded core structure are not connected void volumes on the other side of the folded core structure.

Without being bound to theory, it is believed that a material comprising such a folded core structure has an excellent dimensional stability, in terms of improved stretching resistance, compression resistance and shear resistance, at least in the machine direction and cross machine direction. Further, the used folded core structure comprises a huge amount of void volumes, the material is light weight in view of the floor backings of the prior art.

Within the scope of the present invention “machine direction” is understood to be the direction of production, as it is the largest dimension of the flooring composite, which can also be synonymously called x-direction. Further, the “cross machine direction” is the second largest dimension of the flooring composite, which is in plane with the machine direction and perpendicular to the machine direction, which can be synonymously called y-direction. Out of the plane and perpendicular to the machine direction and the cross machine is the third largest dimension of the flooring composite, which is the z-direction.

In a preferred embodiment, the relaxed honeycomb structure comprises half-cells having a diameter dhaif of 0.5 mm to 30 mm, preferably of 1 to 20 mm, and more preferably of 1 to 15 mm, even more preferably of 1 to 10 mm, and most preferably of 1.5 to 5 mm.

In contrast to the half-closed honeycomb structure, the relaxed honeycomb structure is not fully folded, such that the connection area of a honeycomb cell comprises a kink. Thus, the diameter of the half-cells dhaif of the relaxed honeycomb structure is determined by measuring the distance between the kink and the cell wall of the half-cell of the relaxed honeycomb structure in the plane of the connection area, which is oriented parallel to the kink, wherein the distance is measured perpendicular to the kink and perpendicular to the parallel oriented honeycomb cell wall. To provide the diameter of the honeycomb cells of the relaxed honeycomb structure, the diameters dhaif of both half-cells, which share the same connection area having a kink, have to be summed up (Fig. 3 and 6).

Preferably, the honeycomb cells comprised in the relaxed honeycomb structure have a diameter of 1 mm to 60 mm, preferably of 2 to 40 mm, and more preferably of 2 to 30 mm, even more preferably of 2 to 20 mm, and most preferably of 3 to 10 mm.

In another preferred embodiment, the half-cells of the relaxed honeycomb structure have a height h of 1 mm to 60 mm, preferably of 2 mm to 20 mm, and more preferably of 3 to 15 mm, and most preferably of 3 to 10 mm.

In a further preferred embodiment, the half-cells of the half-closed honeycomb structure have a height h of 1 mm to 60 mm, preferably of 1.5 mm to 20 mm, and more preferably of 1.5 to 15 mm, and most preferably of 2 to 10 mm. The method of determining the height of the half-cells of the half-closed honeycomb structure is also applicable to the half-cells of the relaxed honeycomb structure. The distance, i.e. the diameter and the height of the honeycomb cells are indicated by dashed lines in Figures 3, 5 and 6.

In another preferred embodiment, the half-cells of the relaxed honeycomb structure have a height h of 1 mm to 60 mm, preferably of 1.5 mm to 20 mm, and more preferably of 1.5 to 15 mm, and most preferably of 2 to 10 mm.

Preferably, the honeycomb cells comprised in the half-closed honeycomb structure or the relaxed honeycomb structure have a diameter of 1 mm to 60 mm, preferably of 2 to 40 mm, and more preferably of 2 to 30 mm, even more preferably of 2 to 20 mm, and most preferably of 3 to 10 mm and/or the honeycomb cells have a height of 1 mm to 60 mm, preferably of 1.5 mm to 30 mm, and more preferably of 1.5 to 20 mm, and most preferably of 2 to 10 mm.

In a further preferred embodiment, the folded core structure is a half-closed honeycomb structure.

The advantage of a folded core structure, which is a half-closed honeycomb structure, is that the folded core structure has an improved dimensional stability, at least in z-direction, as the half-cell walls are directed perpendicular to the plane of the folded core structure.

In a preferred embodiment, the folded core structure comprises adjoining cell walls of neighboring half-cell walls in the half-closed honeycomb structure, which are bonded to each other (Fig. 1 , 104a-d). Thereby, bonded to each other has to be understood that the adjoining cell walls of neighboring half cells are connected at least at two edges of each cell wall. Preferably, full surfaces of the adjoining cell walls of neighboring half cells are bonded to each other.

The adjoining cell walls can be bonded to each other by any suitable method such as mechanical bonding, chemical bonding and/or thermal bonding. Preferably, the adjoining cell walls are bonded chemically and/or thermally.

In the case, the adjoining cell walls are bonded to each other, the folded core structure has an improved dimensional stability in any direction as stretching resistance and/or contraction resistance of the folded core structure is eliminated or at least reduced. Further, due to the bonding of the adjoining cell walls, the folded core structure also exhibits an improved bending stiffness and resistance against shear forces.

In another preferred embodiment, the synthetic polymer of the folded core structure comprises a thermoplastic polymer material or thermoplastic elastomeric polymeric material.

Without being bound to theory, it is believed that if the folded core structure comprises a thermoplastic elastomeric polymeric material, the folded core structure has an improved deformability and the ability to return to the original shape and/or improved dampening character. Also, a broadloom carpet and/or a carpet tile comprising the folded core structure comprising a thermoplastic elastomeric polymeric material may have an improved dampening character, such that walking of a person on the broadloom carpet and/or carpet tile has a comfortable feeling.

Thereby, the thermoplastic polymeric material is preferably selected from a group consisting of polyolefins, in particular polyethylene (PE) or polypropylene (PP), polyesters, in particular polyethylene terephthalate (PET), polytrimethylene terephthalate (PTT), polybutylene terephthalate (PBT) or polyetylene-1 ,2- furandicaboxylate (PEF), polyamides, in particular polyamide 6 (PA6) or polyamide 6,6 (PA6,6), polyetherketones (PEK), polyetheretherketones (PEEK), polyetherketoneketones (PEKK), polyvinyl butyral (PVB), polycarbonate (PC), polyether, polyetheresters, copolymers blends and combinations thereof.

In another preferred embodiment, the thermoplastic polymeric material of the folded core structure comprises a multi-layered laminate. Preferably, the thermoplastic polymeric material of the multi-layered laminate is selected from a group consisting of polyolefins, in particular polyethylene (PE) or polypropylene (PP), polyesters, in particular polyethylene terephthalate (PET), polytrimethylene terephthalate (PTT), polybutylene terephthalate (PBT) or polyetylene-1 ,2- furandicaboxylate (PEF), polyamides, in particular polyamide 6 (PA6) or polyamide 6,6 (PA6,6), polyetherketones (PEK), polyetheretherketones (PEEK), polyetherketoneketones (PEKK), polyvinyl butyral (PVB), polycarbonate (PC), polyether, polyetheresters, copolymers and blends thereof.

An example of such a laminate can comprise a copolymer and homopolymer of e.g. polyethylene terephthalate. Such a multi-layered laminate can be a PET-GAG, wherein the laminate comprise glycol modified polyethylene terephthalate (PET-G) and amorphous polyethylene terephthalate (PET-A).

In a preferred embodiment, the multi-layered laminate is a three-layered laminate comprising a core layer a first sheath layer and a second sheath layer. The layers are oriented co-planar to each other, and second sheath layer is located co-planar at one side of the core layer, which is facing away from the first sheath layer. Preferably, the core layer has a melting temperature higher than the melting temperature of the first sheath layer and/ the second sheath layer. Preferably, the melting temperature is at least 5°C, preferably 10°C, more preferably 15°C and most preferably 20°C higher than the melting temperature of the first sheath layer and/or the second sheath layer. In another preferred embodiment, the three-layered laminate can be one of the combinations e.g. PP/PET/PP, PA/PET/PA, PVB/PA/PVB, PVB/PET/PVB or PET- GAG.

The thermoplastic polymeric material and the thermoplastic elastomeric polymeric material of the folded core structure can comprise suitable additives such as flame retardants, antioxidants, fungicides, plasticizer and/or filler materials.

Preferably, the filler materials are particles such as talcum and grinded stone hard particles. In a preferred embodiment, the filler material has a weight of at least 10 wt.-%, preferably of at least 20 wt.-%, more preferably of at least 30 wt.-%, and most preferably of at least 40 wt.-% in view of the weight of the folded core structure.

Without being bound to theory, it is believed that by having grinded stone hard particles added to the thermoplastic polymeric material or to the thermoplastic elastomeric polymeric material, the folded core structure comprises an improved hardness and heat distortion temperature.

In a further preferred embodiment, the folded core structure is water impermeable and the void volumes on one side of the folded core structure are not connected to void volumes on the other side of the folded core structure.

Since the folded core structure can be water impermeable, the folded core structure can be used as a water barrier. Thus, the flooring composite can also be used at locations having high humidity and/or on moist grounds.

In a preferred embodiment, the void volumes in at least one side of the folded core structure is filled with a substrate. Preferably, the substrate is a heated fluid or solid particles. The heated fluid can be a heated thermoplastic polymeric material or a heated thermoplastic elastomeric polymeric material. The solid particles can talcum or grinded stone hard particles.

The filling of the void volumes can increase the weight of the flooring composite, if necessary, which could improve the grip of the flooring composite on the ground.

In a preferred embodiment, the folded core structure comprises heating means, cooling means, lighting, data sensing, data transferring, cables and/or further electrical component such as smart home components.

The heating means can be wires, spot or films of conductive component. The conductive component can comprise any suitable conductive metal such as copper, iron, aluminum, lead, zinc, tin, nickel, chromium, platinum, palladium, silver, gold, and any alloy or combination thereof. Thereby, the heating means can heat the material by conducting electricity through the conductive material or by infrared irradiation of the conductive material.

Heating means can also be small tubes in which a heated medium can flow through, such as in an underfloor heating.

The cooling means can be tubes comprising a cooling fluid. Thereby, the cooling tubes may be connected to a cooling aggregate.

The heating means, cooling means, and/or cables are preferably located in the folded core structure. Preferably, the heating means, cooling means, and/or cables are located in the void volumes in the relaxed honeycomb structure or in channels provided in the folded core structure.

Channels in the folded core structure can be provided, at least in a half-closed honeycomb structure, by comprising rows of honeycomb cells having a smaller height compared to honeycomb cells having a larger height next to the honeycomb cells having the smaller height. By having rows of honeycomb cells having a smaller height than the honeycomb cells having a larger height next to the honeycomb cells having a smaller height, a channel is established, in which heating means, cooling means, and/or cables can be introduced.

In a preferred embodiment, the folded core structure comprises a first main surface and a second main surface and comprises a skin layer on at least one of the main surfaces of the folded core structure.

The first main surface and the second main surface of the folded core structure are preferably parallel to each other, wherein a distance between the first main surface and the second main surface corresponds to the thickness of the folded core structure.

The skin layer can be bonded to the folded core structure chemically, thermally and/or mechanically. Thereby, the skin layer bonded on at least one of the main surfaces of the folded core structure can improve the dimensional stability at least in the plane of the skin layer, i.e. in machine direction and cross machine direction. It is also possible that the skin layer bonded to at least one of the main surfaces of the folded core structure also improves the dimensional stability in z-direction as due to the bonded skin layer, the folded core structure is fixed in its folding.

The skin layer can be a two-dimensional (2D) layer and may consists of a material selected from a group comprising a woven, a nonwoven such as a spunbonded or spun laid nonwoven, a melt blown nonwoven, a carded nonwoven, a needle punched nonwoven, an air laid nonwoven, a hydroentangled nonwoven, and a wet laid nonwoven, a knitted fabric, a net, a scrim, a two-dimensional mat of extruded entangled filaments, a consolidated layer of unidirectional fibers, a continuous film, a discontinuous film, a paper, or a combination thereof. Within the scope of the invention, the term “nonwoven” has to be understood as according to the EDANA (European Disposables and Nonwovens Association) and ISO 9092: A nonwoven is an engineered fibrous assembly, primarily planar, which has been given a designed level of structural integrity by physical and/or chemical means, excluding weaving, knitting or paper making.

The nonwoven can comprise any suitable fibers. Preferably, the nonwoven comprises synthetic fibers, natural fibers and/or recycled fibers.

Within the scope of the invention, the terms “spunbonded nonwoven” and “spun- laid nonwoven”, has to be understood that the nonwoven is manufactured by extruding the fibers from a spinneret and subsequently laying down on a conveyor belt as a web of filaments and subsequently bonding the web to form a nonwoven layer of fibers, or by a two-step process wherein filaments are spun and wound on bobbins, preferably in the form of multifilament yarns, followed by the steps of unwinding the multifilament yarns and laying the filaments down on a conveyor belt as a web of filaments and bonding the web to form a nonwoven layer of fibers.

The continuous film and/or the discontinuous films can be provided by coating e.g. a thermoplastic polymeric material and/or a thermoplastic elastomeric polymeric material.

The woven, nonwovens, scrims, nets, unidirectional fibers or knitted fabric of the skin layer may comprise mineral fibers, such as for example glass, basalt or rockwool fibers, and/or fibers composed of thermoplastic polymeric material or thermoplastic elastomeric polymeric material. Preferably, the skin layer comprises fibers.

The fibers may have any cross-sectional shape, including round, trilobal, multi- lobal or rectangular, the latter exhibiting a width and a height wherein the width may be considerably larger than the height, so that the fiber in this embodiment is a tape.

Within the scope of the present invention it is understood that the term fibers refers to both staple fibers and filaments. Staple fibers are fibers which have a specified, relatively short length in the range of 2 to 200 mm. Filaments are fibers having a length of more than 200 mm, preferably more than 500 mm, more preferably more than 1000 mm. Filaments may even be virtually endless, for example when formed by continuous extrusion and spinning of a filament through a spinning hole in a spinneret. Further, by using the term fibers also yarns comprising fibers or filaments are encompassed.

In an embodiment, the fibers comprised in the skin layer are filaments or staple fibers. Preferably, the fibers comprised in the skin layer are filaments.

In the case, the fibers comprised in the skin layer are filaments, the dimensional stability of the textile fabric, at least in plane of the skin layer is improved due to the fact that forces affecting on the skin layer can be distributed along the whole length of the filaments and thus over an enlarged area of the skin layer.

Preferably, the fibers comprised in the skin layer of the skin layer are bonded at their crossing points. This will improve the aforementioned effect.

The bonding of the fibers comprised in the skin layer can be chemical bonding, mechanical bonding and/or thermal bonding. Preferably, the bonding of the fibers comprised in the skin layer is a chemical bonding and/or thermal bonding.

Preferably, the fibers comprised in the skin layer are composed of a thermoplastic polymeric material or a thermoplastic elastomeric polymeric material.

The fibers comprised in the skin layer can be monofilaments, multifilament yarns, mono-component fibers, two types of mono-component fibers and/or multicomponent fibers, in particular bicomponent fibers. The bicomponent fibers may be of a side-by-side model, concentric or eccentric core/sheath model or islands-in-the-sea model.

In an embodiment, the mono-component fibers comprised in the skin layer comprise of a thermoplastic polymeric material or a thermoplastic elastomeric polymeric material.

Preferably, the mono-component fibers comprised in the skin layer are composed of a thermoplastic polymer selected from a group consisting of polyolefins, in particular polyethylene (PE) or polypropylene (PP), polyesters, in particular polyethylene terephthalate (PET), polytrimethylene terephthalate (PTT), polybutylene terephthalate (PBT) or polyetylene-1 ,2-furandicaboxylate (PEF), polyamides, in particular polyamide 6 (PA6) or polyamide 6,6 (PA6,6), polyetherketones (PEK), polyetheretherketones (PEEK), polyetherketoneketones (PEKK), polyvinyl butyral (PVB), polycarbonate (PC), polyethers, polyetheresters, copolymers and mixtures thereof.

In a preferred embodiment, the fibers comprised in the skin layer are bicomponent fibers of the core/sheath model. Preferably, the core and the sheath of the bicomponent fibers comprised in the skin layer are composed of a thermoplastic polymeric material and/or a thermoplastic elastomeric polymeric material.

By using bicomponent fibers comprising thermoplastic polymers and/or thermoplastic elastomeric polymers, the bicomponent fibers can combine the properties of a certain tensile strength of the core of the bicomponent fibers as well as a certain bonding strength between the fibers. This is possible if the thermoplastic polymeric material or thermoplastic elastomeric polymeric material of the sheath has a lower melting temperature than the core. Thus, the sheath can be at least partially melted, such that bicomponent fibers can be adhered together by the sheath and comprising at the same time the non-deteriorated properties of the core. For the core and the sheath of the bicomponent fibers comprised in the skin layer, any suitable thermoplastic polymer and/or thermoplastic elastomeric polymer can be used. Preferably, the polymer of the sheath has a melting temperature which is lower than the melting temperature of the polymer of the core.

In an embodiment, the core of the bicomponent fibers comprises a thermoplastic polymeric material or a thermoplastic elastomeric polymeric material.

Preferably, the core of the bicomponent fibers is composed of a thermoplastic polymeric material selected from a group consisting of polyolefins, in particular polyethylene (PE) or polypropylene (PP), polyesters, in particular polyethylene terephthalate (PET), polytrimethylene terephthalate (PTT), polybutylene terephthalate (PBT) or polyetylene-1 ,2-furandicaboxylate (PEF), polyamides, in particular polyamide 6 (PA6) or polyamide 6,6 (PA6,6), polyetherketones (PEK), polyetheretherketones (PEEK), polyetherketoneketones (PEKK), polyvinyl butyral (PVB), polycarbonate (PC), polyethers, polyetheresters, copolymers and mixtures thereof.

In an embodiment, the sheath of the bicomponent fibers comprises a thermoplastic polymeric material or a thermoplastic elastomeric polymeric material.

Preferably, the sheath of the bicomponent fibers is composed of a thermoplastic polymeric material selected from a group consisting of polyolefins, in particular polyethylene (PE) or polypropylene (PP), polyesters, in particular polyethylene terephthalate (PET), polytrimethylene terephthalate (PTT), polybutylene terephthalate (PBT) or polyetylene-1 ,2-furandicaboxylate (PEF), polyamides, in particular polyamide 6 (PA6) or polyamide 6,6 (PA6,6), polyetherketones (PEK), polyetheretherketones (PEEK), polyetherketoneketones (PEKK), polyvinyl butyral (PVB), polycarbonate (PC), polyethers, polyetheresters, copolymers and mixtures thereof.

In the case, the skin layer comprises two-types of mono-component fibers, one type of the two-types of mono-component fibers can be for stability reasons and the other type for bonding reasons.

In a preferred embodiment, the first part of a form-fit connection and the second part of a form-fit connection are both located on the at least one edge of the material.

Without being bound to theory, it is believed that in the case the first part of a form- fit connection and the second part of a form-fit connection are both located on the at least one edge of the material improve the strength of the form-fit connection provided between the material comprising a first part of the form-fit connection and a second part of a form-fit connection on at least one edge of the material and the corresponding counterpart material, when installed.

In another preferred embodiment, the material has any suitable form to provide a form-fit connection. Preferably, the material has a rectangular form or a patterned form such as of the Escher-type. The Escher-type of pattern in known to those skilled in the art. More preferably, the material has a rectangular form having four edges.

It is believed, if the material has a rectangular form, it is easy to install the material with further materials to build up a surface comprising multiple materials, which are connected by the form-fit connections comprising at least a fist part of a form-fit connection and at least a second part of a form-fit connection.

In a further preferred embodiment, at least one edge, preferably at least two edges, more preferably at least three edges and most preferably all edges of the material comprise a first part of a form-fit connection and/or a second part of a form-fit connection.

Thereby, having on more than one edge of the material a first part of a form-fit connection and/or a second part of a form-fit connection, the material can build up with other materials a surface comprising multiple surface connected to each other. Preferably, all edges of the material comprise a first part of a form-fit connection and a second part of a form-fit connection.

By combining a first part of a form-fit connection and a second part of a form-fit connection on the same edge and connecting this edge with a counterpart material, may improve the connection strength between these two materials. Further, for example the first part of a form-fit connection is located at an edge of the material along a half of the edge and the second part of the form-fit connection is located at an edge of the material along the other half of the edge, it is possible to connect two materials offset to each other, thus two counterpart materials are connected partially to one edge of a material.

Without being bound to theory, it is believed that if the materials are connected offset to each other, the shear strength of the connections of the material is improved.

As explained above, having a first part of a form-fit connection on at least one edge of the material, this will improve the strength of the connection between two materials.

The first part of a form-fit connection and the second part of a form-fit connection can be manufactured by any suitable method, preferably, the first part of a form-fit connection and the second part of a form-fit connection is provided by using vacuum, pressure, heat, or a combination thereof. Preferably, the first part of a form-fit connection and the second part of a form-fit connection are provided by a thermoforming process.

Within the scope of the invention, the term “thermoforming process” has to be understood as a manufacturing process where a plastic material is heated to a temperature, in which the plastic material is formable into a specific shape in a mold, or trimmed to create a product and subsequently the plastic material is cooled down to solidify in the new form. Typically, the temperature can be equal to or higher than the softening temperature of a plastic material. Such a thermoform process can be carried out as a continuous process and also as a discontinuous process.

In the thermoforming process of the first part of a form-fit connection and the second part of a form-fit connection, wherein the first part and the second part of a form-fit connection comprise at least deformed synthetic polymer originating from the folded core structure, at least a part of the folded core structure is heated to a temperature equal to or higher than the softening temperature of the synthetic polymer comprised in the folded core structure.

Preferably, the part of the folded core structure, which is heated, is located at least on an edge of the folded core structure.

The synthetic polymer comprised in the folded core structure can be heated by any suitable method. Preferably the synthetic polymer comprised in the folded core structure is heated by heated molds, infrared irradiation, microwave irradiation, induction, heated air, or any heated fluid.

Subsequently, the heated synthetic polymer comprised in the folded core structure can be thermoformed into a form of the first part of a form-fit connection and/or into a form of the second part of a form-fit connection. Thereby, a mold can be used, which can have the negative form of the first part of a form-fit connection and a mold which can have the negative form of the second part of a form-fit connection. Typically, the mold used for providing the first part of a form-fit connection has the form of the second part of the form-fit connection and vice versa.

The mold can comprise heating and/or cooling means. The heating means of the mold can be used to heat the synthetic polymer comprised in the folded core structure. The cooling means of the mold can be used to cool down the thermoformed synthetic polymer.

After the heated synthetic polymer comprised in the folded core structure is formed into the first part of a form-fit connection and/or into the second part of a form-fit connection, the synthetic polymer of the first part of a form-fit connection and/or of the second part of a form-fit connection is cooled to provide a solid first part of a form-fit connection and/or a solid second part of a form-fit connection.

The cooling of the of the first part of a form-fit connection and/or the second part of a form-fit connection can be performed by any suitable method. Preferably, the cooling of the of the first part of a form-fit connection and/or the second part of a form-fit connection can be performed by a cooling fluid such as air or water, or by the mold comprising cooling means.

In a preferred embodiment, by forming the heated synthetic polymer of the folded core structure into the first part of a form-fit connection and/or the second part of a form-fit connection, an additional synthetic polymer can be injected into the mold.

In another preferred embodiment, the synthetic polymer forming the first part of a form-fit connection and the second part of a form-fit connection comprises additives such as flame retardants, antioxidants, fungicides, plasticizer and/or filler materials. Preferably, the filler materials are particles such as talcum and grinded stone hard particles. In a preferred embodiment, filler material has a weight of at least 10 wt.- %, preferably of at least 20 wt.-%, more preferably of at least 30 wt.-%, and most preferably of at least 40 wt.-% in view of the weight of the folded core structure..

Without being bound to theory, it is believed that by having grinded stone hard particles and/or talcum added to the synthetic polymer forming the first part of a form-fit connection and/or the second part of a form-fit connection, the first part of a form-fit connection and/or the second part of a form-fit connection and also the form-fit connection comprising first part of a form-fit connection and/or the second part of a form-fit connection comprise an improved stiffness and also an improved dimensional stability. Forming the first part of a form-fit connection and/or the second part of a form-fit connection can be performed by any suitable method, preferably by thermal molding. Additionally, the forming can be performed by any mechanical shaping such as cutting, grinding, skiving and/or shaving.

The material may comprise at least one additional layer on the second main surface of the folded core structure.

In a preferred embodiment, the additional layer can be a two-dimensional (2D) layer and may consist of a material selected from a group comprising a woven, a nonwoven such as a spunbonded or spun laid nonwoven, a melt blown nonwoven, a carded nonwoven, a needle-punched nonwoven, an air laid nonwoven, a hydroentangled nonwoven, and a wet laid nonwoven, a knitted fabric, a net, a scrim, a two-dimensional mat of extruded entangled filaments, a consolidated layer of unidirectional fibers, a continuous film, a discontinuous film, a paper, or a combination thereof. Preferably, the at least one additional layer is a fluffy nonwoven, more preferably, the at least one additional layer is a fluffy carded nonwoven. Without being bound to theory, it is believed that if a fluffy nonwoven, e.g. a carded nonwoven, is used as additional layer, this improves the acoustic properties of the flooring composite.

The at least one additional layer may also be a three-dimensional (3D) layer and may consist of a material selected from a group comprising a three-dimensional nonwoven, a foam, a three-dimensional structured mat of extruded filaments, a further folded core structure, knitted spacer fabrics, woven spacer fabrics, corrugated sheets, dimple drain materials, a ridged surface material or a combination thereof.

The three-dimensional nonwoven can be provided from a two-dimensional nonwoven by three-dimensional shaping the nonwoven by e.g. thermoforming.

The thermoforming can be performed by heated profiled rolls. In the case the nonwoven comprises bicomponent fibers, such as core sheath type bicomponent fibers, and the nonwoven is thermoformed by heated profiled rolls, the sheath of the bicomponent fiber, which is melted by the heated rolls, is responsible for retaining the three-dimensional shape. An example of such a three-dimensional nonwoven is disclosed by EP 1620254 B1.

The fibers may have any cross-sectional shape, including round, trilobal, multi- lobal or rectangular, the latter exhibiting a width and a height wherein the width may be considerably larger than the height, so that the fiber in this embodiment is a tape.

Preferably, the filaments of the three-dimensional structured mat of extruded entangled filaments are extruded polymeric filaments. A three-dimensional structured mat of extruded entangled filaments may be provided by any suitable process. Preferably, the three-dimensional structured mat of extruded entangled filaments is provided by extruding polymeric filaments and collecting the extruded filaments into a three-dimensional structure by allowing the filaments to bend, to entangle and to come into contact with each other, preferably in a still molten state. Bending and entangling of the extruded filaments are preferably initiated by collecting the filaments onto a profiled surface, which defines the structure of the three-dimensional structured mat of extruded entangled filaments. Preferably, the surface on which the filaments are collected is profiled such that the three- dimensional structured mat of filaments is shaped into a three-dimensional form which comprises hills and valleys, hemispheres, positive and/or negative cuspates, cups and/or waffles, pyramids, U-grooves, V-grooves, cones and/or cylinders capped with a hemisphere.

In another preferred embodiment, the at least one additional layer is laminate of at least one three-dimensional layer and at least one two-dimensional layer.

In another preferred embodiment, the additional layer is an underfloor heating and/or a drainage layer.

In a preferred embodiment, all parts of the material, e.g. the folded core structure, the first part of a form fit connection, the second part of a form-fit connection, the skin layer, and the at least one additional layer, comprise a thermoplastic polymer or a thermoplastic elastomeric polymer. Preferably, the thermoplastic polymeric material is selected from a group consisting of polyolefins, in particular polyethylene (PE) or polypropylene (PP), polyesters, in particular polyethylene terephthalate (PET), polytrimethylene terephthalate (PTT), polybutylene terephthalate (PBT) or polyetylene-1 ,2-furandicaboxylate (PEF), polyamides, in particular polyamide 6 (PA6) or polyamide 6,6 (PA6,6), polyetherketones (PEK), polyetheretherketones (PEEK), polyetherketoneketones (PEKK), polyvinyl butyral (PVB), polycarbonate (PC), polyether, polyetheresters, copolymers and mixtures thereof. All parts of the material can be composed of different polymers, but preferably all parts of the material are composed of one thermoplastic polymer or one thermoplastic elastomeric polymer or of a single polymer family.

Within the scope of the invention, a polymer family has to be understood that the polymers of one family are composed of at least 50 % of the same monomeric units.

Preferably, all parts of the material are composed of thermoplastic polymers or thermoplastic elastomeric polymers, which are constituted of at least 50 %, preferably of at least 60 %, more preferably of at least 70 %, even more preferably of at least 80 %, even more preferably of at least 90 %, even more preferably of at least 95 %, and most preferably of 100 % of the same monomeric units.

In the case, all parts of the material are constituted of the same thermoplastic polymeric material or thermoplastic elastomeric polymeric material or of the same family of thermoplastic polymeric material or thermoplastic elastomeric polymeric material, the material can be easily recycled.

In another preferred embodiment, the at least one additional layer is an underfloor heating and/or a drainage layer.

The object is also solved by a process for manufacturing a material by providing a folded core structure comprising a synthetic material, forming a first part of a form- fit connection on at least one edge of the material at least from the synthetic polymer of the folded core structure, and forming a second part of a form-fit connection on at least one edge of the material at least from the synthetic polymer of the folded core structure.

Any of the aforementioned embodiments of the material can also be applicable to the process for manufacturing a material. The object is also solved by a modular flooring comprising a base layer and a cover layer, wherein the base layer is bonded to the cover layer, characterized in that the base layer is a material according to any of the aforementioned embodiments.

The bonding between the base layer and the cover layer can be a mechanical bonding, a chemical bonding and/or a thermal boding.

Thereby, the synthetic polymer comprised in the base layer can be used for bonding the cover layer to the base layer.

Preferably, the modular flooring comprises a fixation layer, which binds the base layer to the cover layer.

The fixation layer can be a two-dimensional (2D) layer and may consists of a material selected from a group comprising a woven, a spunbonded or spun laid nonwoven, a melt blown nonwoven, a carded nonwoven, a needle-punched nonwoven, an air laid nonwoven, a wet laid nonwoven, a knitted fabric, a net, a scrim, a two-dimensional mat of extruded entangled filaments, a consolidated layer of unidirectional fibers, a continuous film, a discontinuous film, or a combination thereof.

In an embodiment, the fibers comprised in the skin layer are filaments or staple fibers. Preferably, the fibers comprised in the skin layer are filaments.

In the case, the fibers comprised in the skin layer are filaments, the dimensional stability of the textile fabric, at least in plane of the skin layer is improved due to the fact that forces affecting on the skin layer can be distributed along the whole length of the filaments and thus over an enlarged area of the skin layer. Preferably, the fibers comprised in the skin layer of the skin layer are bonded at their crossing points. This will improve the aforementioned effect.

The bonding of the fibers comprised in the skin layer can be chemical bonding, mechanical bonding and/or thermal bonding. Preferably, the bonding of the fibers comprised in the skin layer is a chemical bonding and/or thermal bonding.

The woven, nonwovens, scrims, nets, unidirectional fibers or knitted fabric of the fixation layer may comprise mineral fibers, such as for example glass, basalt or rockwool fibers, and/or fibers composed of thermoplastic polymeric material or thermoplastic elastomeric polymeric material.

Preferably, the fibers comprised in the fixation layer are composed of a thermoplastic polymeric material or a thermoplastic elastomeric polymeric material.

The fibers comprised in the fixation layer can be monofilaments, multifilament yarns, mono-component fibers, two types of mono-component fibers and/or multicomponent fibers, in particular bicomponent fibers. The bicomponent fibers may be of a side-by-side model, concentric or eccentric core/sheath model or islands-in-the-sea model.

In an embodiment, the mono-component fibers comprised in the fixation layer comprise of a thermoplastic polymeric material or a thermoplastic elastomeric polymeric material.

Preferably, the mono-component fibers comprised in the fixation layer are composed of a thermoplastic polymer selected from a group consisting of polyolefins, in particular polyethylene (PE) or polypropylene (PP), polyesters, in particular polyethylene terephthalate (PET), polytrimethylene terephthalate (PTT), polybutylene terephthalate (PBT) or polyetylene-1 ,2-furandicaboxylate (PEF), polyamides, in particular polyamide 6 (PA6) or polyamide 6,6 (PA6,6), polyetherketones (PEK), polyetheretherketones (PEEK), polyetherketoneketones (PEKK), polyvinyl butyral (PVB), polycarbonate (PC), polyether, polyetheresters, copolymers and mixtures thereof.

In a preferred embodiment, the fibers comprised in the fixation layer are bicomponent fibers of the core/sheath model. Preferably, the core and the sheath of the bicomponent fibers comprised in the skin layer comprise a thermoplastic polymer and/or a thermoplastic elastomeric polymer.

By using bicomponent fibers comprising thermoplastic polymers and/or thermoplastic elastomeric polymers, the bicomponent fibers can combine the properties of a certain tensile strength of the core as well as a certain bonding strength between the fibers. This is possible if the thermoplastic polymeric material or thermoplastic elastomeric polymeric material of the sheath has a lower melting temperature than the core. Thus, the sheath can be at least partially melted, such that bicomponent fibers can be adhered together by the sheath and comprising at the same time the non-deteriorated properties of the core. Further, as the sheath of the bicomponent fibers can also be used as an adhesive for bonding the base layer and the cover layer.

For the core and the sheath of the bicomponent fibers comprised in the fixation layer, any suitable thermoplastic polymer and/or thermoplastic elastomeric polymer can be used. Preferably, the polymer of the sheath has a melting temperature which is lower than the melting temperature of the polymer of the core.

In an embodiment, the core of the bicomponent fibers comprises a thermoplastic polymeric material or a thermoplastic elastomeric polymeric material. Preferably, the core of the bicomponent fibers comprises a thermoplastic polymeric material selected from a group consisting of polyolefins, in particular polyethylene (PE) or polypropylene (PP), polyesters, in particular polyethylene terephthalate (PET), polytrimethylene terephthalate (PTT), polybutylene terephthalate (PBT) or polyetylene-1 ,2-furandicaboxylate (PEF), polyamides, in particular polyamide 6 (PA6) or polyamide 6,6 (PA6,6), polyetherketones (PEK), polyetheretherketones (PEEK), polyetherketoneketones (PEKK), polyvinyl butyral (PVB), polycarbonate (PC), polyether, polyetheresters, copolymers and mixtures thereof.

In an embodiment, the sheath of the bicomponent fibers comprises a thermoplastic polymeric material or a thermoplastic elastomeric polymeric material.

Preferably, the sheath of the bicomponent fibers is composed of a thermoplastic polymeric material selected from a group consisting of polyolefins, in particular polyethylene (PE) or polypropylene (PP), polyesters, in particular polyethylene terephthalate (PET), polytrimethylene terephthalate (PTT), polybutylene terephthalate (PBT) or polyetylene-1 ,2-furandicaboxylate (PEF), polyamides, in particular polyamide 6 (PA6) or polyamide 6,6 (PA6,6), polyetherketones (PEK), polyetheretherketones (PEEK), polyetherketoneketones (PEKK), polyvinyl butyral (PVB), polycarbonate (PC), polyether, polyetheresters, copolymers and mixtures thereof.

In a preferred embodiment, the skin layer comprises monofilaments, multifilament yarns, mono-component fibers, two types of mono-component fibers and/or multicomponent fibers, in particular bicomponent fibers.

In the case, the skin layer comprises two-types of mono-component fibers, one type of the two-types of mono-component fibers can be for stability reasons and the other type for bonding reasons. In principle any kind of adhesive compound having at least adhesive properties can be applied as fixation layer between the base layer and the cover layer. Examples for such adhesive compounds can be thermoset adhesive, pressure sensitive adhesives, polymer coats, thermo-activatable adhesives and curable mixtures.

In a preferred embodiment, the fixation layer comprises a thermoplastic polymeric material or a thermoplastic elastomeric polymeric material.

Preferably, a thermoplastic polymeric material comprised in the fixation layer is selected from a group consisting of polyolefins, in particular polyethylene (PE) or polypropylene (PP), polyesters, in particular polyethylene terephthalate (PET), polytrimethylene terephthalate (PTT), polybutylene terephthalate (PBT) or polyetylene-1 ,2-furandicaboxylate (PEF), polyamides, in particular polyamide 6 (PA6) or polyamide 6,6 (PA6,6), polyetherketones (PEK), polyetheretherketones (PEEK), polyetherketoneketones (PEKK), polyvinyl butyral (PVB), polycarbonate (PC), polyethers, polyetheresters, copolymers and mixtures thereof.

Preferably, the base layer and the cover layer is bonded together by the fixation layer, wherein the bonding is a thermal bonding and or a chemical bonding.

In a preferred embodiment, the cover layer is a tufted carpet, a vinyl flooring, a laminate, a ply of wood, a ply comprising minerals such as plies of stones or ceramic tiles.

In another preferred embodiment, the base layer, the fixation layer and/or the cover layer comprise heating means.

The heating means can be wires, spot or films of conductive component. The conductive component can comprise any suitable conductive metal such as copper, iron, aluminum, lead, zinc, tin, nickel, chromium, platinum, palladium, silver, gold, and any alloy or combination thereof. Thereby, the heating means can heat the base layer, respectively the modular flooring, by conducting electricity through the conductive material or by infrared irradiation of the conductive material.

Fleating means can also be small tubes in which a heated medium can flow through, such as in an underfloor heating.

In a preferred embodiment, the material comprised in the modular flooring comprises a closing edge at at least one edge of the material. The closing edge may comprise a slope, fringes, bands and/or ribbons.

The closing edge comprised in the material can have the advantage of an improved visual appearance if the modular flooring is laid on a ground without ending directly next to a wall.

Figure 1 : Schematic cross section of a modular flooring Figure 2: Schematic cross section of a modular flooring Figure 3: Schematic perspective view of a part of a relaxed honeycomb structure

Figure 4: Schematic cross-sectional view of a relaxed honeycomb structure. Figure 5: Schematic top view of a honeycomb cell. Figure 6: Schematic perspective view of a part of a honeycomb cell of a relaxed honeycomb structure.

Figure 7 Schematic cross-sectional view of a fully folded honeycomb cell of a honeycomb structure.

Figure 1 shows a part of a cross section of a modular flooring 100 comprising a cover layer 106 and a base layer 102. The base layer comprises a folded core structure 101 , a first part of a form-fit connection 107a, and a second part of a form-fit connection 107b. The first part of a form-fit connection 107a comprises a projections (male part, not indicated), which fits very well into the indentation (female part, not indicated) of the second part of a form fit connection 107b. The folded core structure 101 is a half-closed honeycomb structure comprising honeycomb cells 103, which are delimited by cell walls. Thereby, the half-closed honeycomb structure 101 has neighboring honeycomb cells which have adjoining cell walls 104a and 104b which are in contact to each other. 104a and 104b indicates these adjoining cell walls for a first row of honeycomb cells, the dashed lines indicated by 104c and 104d shows adjoining cell walls of a neighboring row of honeycomb cells in cross machine direction. Further, the honeycomb cells 103 of the half-closed honeycomb structure 101 comprises on one side of each honeycomb cell a connection area 105a or 105b, which closes the honeycomb cells on one side either on the side facing the cover layer 106 or on the side facing away from the cover layer 106. Thereby, the connection area 105a is the connection area for the first row of honeycomb cells, which is on the side of the half-closed honeycomb structure 101 facing the cover layer 106, and the connection area 105b is the connection area of the neighboring row of honeycomb cells in cross machine direction, which is on the side of the half-closed honeycomb structure 101 facing away from the cover layer 106. Further, the base layer

Figure 2 shows a part of a cross section of a modular flooring 200 comprising a cover layer 206 and base layer 202. The base layer 202 comprises a folded core structure 201 which is a relaxed honeycomb structure, wherein the folding of the plastically deformed uncut flat body is stopped before two half cells 203 meet together, a first part of a form-fit connection 207a, and a second part of a form-fit connection 207b. The first part of a form-fit connection 207a comprises a projections (male part, not indicated), which fits very well into the indentation (female part, not indicated) of the second part of a form fit connection 207b. The relaxed honeycomb structure 201 is preferably in contact with the base layer 206 by the edges 203a, and preferably in contact with the ground (not shown) by the edges 203b. Figure 3 shows a part of a relaxed honeycomb structure 300 half cells 308 having a height h and a half diameter dhaif. Also, the relaxed honeycomb structure 300 comprises kinks 309 and connection areas 305a. The machine direction MD and cross machine direction CD are indicated by arrows.

Figure 4 shows a side view of a relaxed honeycomb structure 402, which has an angle a between two in machine direction consecutive half cells 410 and 412. Thereby, the two half cells 410 and 412 are folded such that an angle a is established by the corner points 411a-c and 411 d-f. The machine direction MD and cross machine direction CD are indicated by arrows.

Figure 5 shows a schematic top view of a honeycomb cell 500. In this honeycomb cell 500 the diameter d is the perpendicular distance between two parts 513a of two consecutive half cells of the honeycomb structure in machine direction, which are oriented parallel to each other. The machine direction MD and cross machine direction CD are indicated by arrows.

Figure 6 shows a schematic perspective view of a part of a honeycomb cell of a relaxed honeycomb structure 600 comprising a kink 609 and a cell wall of the half cells of the relaxed honeycomb structure 613, which is oriented parallel to the kink 609. The diameter of the honeycomb cells of the relaxed honeycomb structure is determined by measuring the diameter dhaif between the kink 609 and the cell wall of the half-cell of the relaxed honeycomb structure 613, which is perpendicular to the kink 609 and perpendicular to the plane of the cell wall 613, and sum up the diameters dhaif of two half cells, which share the same kink 609. The partially dashed lines 614 indicates the half-cell of the relaxed honeycomb structure. The machine direction MD and cross machine direction CD are indicated by arrows.

Figure 7 shows a schematic cross-sectional view of a fully folded honeycomb cell of a honeycomb structure 700 comprising a connection area 705 and honeycomb cell walls 713. The height of the fully folded honeycomb cell 700 is measured as the perpendicular distance between the plane of connection area 705 and the end of the honeycomb walls 713. The machine direction MD and cross machine direction CD are indicated by arrows.