FORMING UNIT AND CELLULOSE BOTTLE

TECHNICAL FIELD

The present disclosure relates to a method for dry-forming a cellulose bottle from an air-formed cellulose blank structure in a bottle forming unit. The disclosure further relates to a bottle forming unit for dry-forming a cellulose bottle from an air-formed cellulose blank structure and a dry-formed cellulose bottle.

BACKGROUND

Cellulose fibres are commonly used as raw material for producing or manufacturing cellulose products. Products formed of cellulose fibres can be used in many different situations where there is a need for sustainable products. A wide range of products can be produced from cellulose fibres and one specific product category relates to cellulose bottles.

Bottle forming units are used when manufacturing cellulose bottles from raw materials including cellulose fibres, and traditionally cellulose products have been produced by wet-forming methods. A material commonly used for wet-forming cellulose fibre products, such as cellulose bottles is wet moulded pulp. Wet-formed products are generally formed by immersing a suction forming mould into a liquid or semi liquid pulp suspension or slurry comprising cellulose fibres, and when suction is applied, a body of pulp is formed with the shape of the desired product by fibre deposition onto the forming mould. With all wet-forming methods, there is a need for drying of the wet moulded product, where the drying process is a time and energy consuming part of the production. The demands on aesthetical, chemical and mechanical properties of cellulose products are increasing, and due to the properties of wet-formed cellulose products, the mechanical strength, flexibility, freedom in material thickness, and chemical properties are limited. It is also difficult in wet-forming processes to control the mechanical properties of the products with high precision. One development in the field of producing cellulose products, such as cellulose bottles, is dry-forming of cellulose products without using wet-forming methods. Instead of forming the cellulose products from a liquid or semi liquid pulp suspension or slurry, an air-formed cellulose blank structure is used. The air-formed cellulose blank structure is inserted into a forming mould and during the dry-forming of the cellulose products, the cellulose blank is subjected to a high forming pressure and a high forming temperature. One difficulty with bottle dry-forming methods is the problem with an efficient production process, where cellulose bottles with high quality can be produced at high speeds. The handling of the air-formed cellulose blank structure is a complicated and time consuming process when dry-forming the cellulose bottles, and there is a need for producing bottles with high finish at increased production rates, and thus a more efficient bottle forming unit and method for producing high-quality cellulose bottles is desired.

SUMMARY

An object of the present disclosure is to provide a method for dry-forming a cellulose bottle, a cellulose bottle forming unit, and a dry-formed cellulose bottle, where the previously mentioned problems are avoided. This object is at least partly achieved by the features of the independent claims. The dependent claims contain further developments of the method for dry-forming a cellulose bottle, the cellulose bottle forming unit, and the dry-formed cellulose bottle.

The disclosure concerns a method for dry-forming a cellulose bottle from an airformed cellulose blank structure in a bottle forming unit. The dry-formed cellulose bottle comprises a neck portion, a closed bottom portion, and a mid-portion arranged between the closed bottom portion and the neck portion. The mid-portion is arranged in fluid communication with the neck portion. The method comprises the steps: shaping the dry-formed cellulose blank structure into a shaped cellulose blank structure, where the shaped cellulose blank structure has a tube-like configuration with an inner surface and an outer surface; feeding a first section of the shaped cellulose blank structure to a first forming mould and forming a semi-closed bottom portion of the cellulose bottle from the first section in the first forming mould, simultaneously with forming the neck portion of a directly preceding cellulose bottle from the first section in the first forming mould; feeding a following second section of the shaped cellulose blank structure to the first forming mould and forming the neck portion of the cellulose bottle from the second section in the first forming mould, simultaneously with forming a semi-closed bottom portion of a directly following cellulose bottle from the second section in the first forming mould.

Advantages with these features are that the method is enabling an efficient production process, where cellulose bottles with high quality can be produced at high speeds. The handling of the air-formed cellulose blank structure is simplified through use of the shaped cellulose blank structure having the tube-like configuration, and the first forming mould is used for efficiently producing bottles with high finish at increased production rates. In this way, a more efficient bottle forming method for producing high-quality cellulose bottles is achieved. The simultaneous forming of the semiclosed bottom portion of the cellulose bottle and the neck portion of a directly preceding cellulose bottle is providing a unique and fast forming operation.

In one embodiment, the first forming mould comprises openable and closable first mould parts arranged around a pressure lance. A first forming cavity is formed between the first mould parts and the pressure lance. The forming of the semi-closed bottom portion of the cellulose bottle in the first forming mould further comprises the steps: opening the first mould parts; feeding the shaped cellulose blank structure around the pressure lance and through the first mould parts; stopping the feeding of the shaped cellulose blank structure when the first section of the shaped cellulose blank structure is arranged in a position aligned with the first mould parts; closing the first mould parts and pressing the first section against the pressure lance by means of the first mould parts for forming the semi-closed bottom portion of the cellulose bottle in the first forming cavity, and simultaneously forming the neck portion of the directly preceding cellulose bottle in the first forming cavity. In this way, a section of the pressure lance is extending through the first forming cavity and forming part of the first forming mould. The section of the pressure lance extending through the first forming cavity is together with the first mould parts used for an efficient forming of the neck portion and the semi-closed bottom portion in the first forming cavity. During the pressing operation, a first forming pressure and a first forming temperature are suitably applied onto the shaped cellulose blank structure in the first forming cavity, for an efficient forming operation in the first forming mould. In one embodiment, the forming of the neck portion of the cellulose bottle in the first forming mould further comprises the steps: opening the first mould parts; feeding the shaped cellulose blank structure around the pressure lance and through the first mould parts; stopping the feeding of the shaped cellulose blank structure when the second section of the shaped cellulose blank structure is arranged in a position aligned with the first mould parts; closing the first mould parts and pressing the second section against the pressure lance by means of the first mould parts for forming the neck portion of the cellulose bottle in the first forming cavity, and simultaneously forming the semi-closed bottom portion of the directly following cellulose bottle in the first forming cavity. The simultaneous forming of the semi-closed bottom portion of the cellulose bottle and the neck portion of a directly preceding cellulose bottle is providing a unique and fast forming operation, and in this way, the semi-closed bottom portion of the cellulose bottle is efficiently formed.

In one embodiment, the forming of the neck portion of the cellulose bottle in the first forming mould further comprises the steps: applying the first forming pressure and the first forming temperature onto a part of the second section of the shaped cellulose blank structure for forming a structurally rigid neck portion. In this way, the neck portion of the cellulose bottle is efficiently formed with a rigid structure for high structural strength and durability through the application of the first forming pressure and the first forming temperature onto the part of the second section used for forming the neck portion.

In one embodiment, the method further comprises the steps: feeding the formed semiclosed bottom portion of the cellulose bottle and an intermediate section of the shaped cellulose blank structure between the formed semi-closed bottom portion of the cellulose bottle and the formed neck portion of the cellulose bottle to a second forming mould; forming the mid-portion of the cellulose bottle from the intermediate section and forming the closed bottom portion of the cellulose bottle from the semi-closed bottom portion in the second forming mould. The second forming mould is in this way used for an efficient forming of the mid-portion of the cellulose bottle from the intermediate section and forming the closed bottom portion of the cellulose bottle from the semi-closed bottom portion after the forming operations in the first forming mould. In one embodiment, the second forming mould comprises openable and closable second mould parts forming a second forming cavity. A flexible membrane connected to and arranged in fluid communication with the pressure lance is arranged in the second forming cavity. The forming of the mid-portion and the closed bottom portion in the second forming mould further comprises the steps: opening the first mould parts and opening the second mould parts; feeding the semi-closed bottom portion and the intermediate section around the pressure lance into the second forming mould; stopping the feeding of the semi-closed bottom portion and the intermediate section when positioned between the open second mould parts; closing the second mould parts around the semi-closed bottom portion and the intermediate section and inflating the flexible membrane with a pressure medium entering from the pressure lance and applying a second forming pressure onto the semi-closed bottom portion and the intermediate section by pressing the semi-closed bottom portion and the intermediate section against the second mould parts by means of the inflated flexible membrane, and applying a second forming temperature onto the semi-closed bottom portion and the intermediate section, for forming the closed bottom portion and the mid-portion; deflating the flexible membrane and opening the second mould parts; removing the formed cellulose bottle from the second forming mould. In this way, the flexible membrane when inflated by the pressure medium is applying the second forming pressure onto the intermediate section and the semi-closed bottom portion. Further, the applied second forming pressure together with the applied second forming temperature onto the semi-closed bottom portion and the intermediate section are efficiently forming the closed bottom portion and the mid-portion of the cellulose bottle.

In one embodiment, upon forming of the semi-closed bottom portion in the first forming mould, a collar section of the semi-closed bottom portion is established by forces acting on the shaped cellulose blank structure. The method further comprises the step: pushing the semi-closed bottom portion towards a closed configuration upon closing the second mould parts of the second forming mould around the semi-closed bottom portion, wherein the collar opening of the semi-closed bottom portion is closed by the forces exerted by the second mould parts. The closed configuration of the semiclosed bottom portion is enabling an efficient forming of the cellulose bottle, where the semi-closed bottom portion can be formed into the fully closed bottom portion in the second forming mould upon application of the second forming pressure and second forming temperature. In one embodiment, the method further comprises the step: closing the first mould parts simultaneously with closing the second mould parts. The simultaneous closing is securing synchronized movements of the mould parts for an increased production speed.

In one embodiment, the bottle forming unit further comprises a cutting device arranged in the second mould part or in connection to the second mould part. The method further comprises the step: cutting off the formed neck portion of the cellulose bottle from the semi-closed bottom portion of the directly following cellulose bottle by means of the cutting device during the forming of the cellulose bottle in the second forming mould. The cutting device may be arranged with cutting edges on the outer second mould part and the inner second mould part respectively for an efficient cutting operation, where the cutting edges are cutting off the formed neck portion of the cellulose bottle from the semi-closed bottom portion of the directly following cellulose bottle upon closing of the second forming mould. According to one example embodiment, where the pressure lance extends into the second forming mould, the cutting device may be arranged to work against and around the pressure lance such that the pressure lance acts as an anvil against which the cutting edges are pressed for separating the neck portion from the semi-closed bottom portion. Here, the pressure lance may comprise a reinforced portion that can withstand the pressure from the cutting edges. The reinforced portion can be arranged as a thicker material portion of the pressure lance and/or can be made from a different material than adjacent pressure lance portions. As an alternative, the entire pressure lance is made from a suitable material than can withstand pressure both in the first forming mould and the second forming mould.

In one embodiment, the first forming mould comprises a thread forming section. The method further comprises the step: forming a threaded section of the neck portion upon forming of the neck portion in the first forming mould by means of the thread forming section. The thread forming section comprises a threaded pattern enabling efficient forming of the threaded section of the neck portion in the first forming mould.

In one embodiment, the directly preceding cellulose bottle is a leading cellulose bottle to the dry-formed cellulose bottle, and the directly following cellulose bottle is a trailing cellulose bottle to the dry-formed cellulose bottle. The disclosure further concerns a bottle forming unit for dry-forming a cellulose bottle from an air-formed cellulose blank structure. The dry-formed cellulose bottle comprises a neck portion, a closed bottom portion, and a mid-portion arranged between the closed bottom portion and the neck portion. The mid-portion is arranged in fluid communication with the neck portion. The bottle forming unit comprises a feeding unit, a shaping unit and a first forming mould. The shaping unit is configured for shaping the dry-formed cellulose blank structure into a shaped cellulose blank structure having a tube-like configuration with an inner surface and an outer surface. The feeding unit is configured for feeding the shaped cellulose blank structure to the first forming mould. The first forming mould is configured for forming a neck portion of a leading cellulose bottle simultaneously with forming a semi-closed bottom portion of a directly following trailing cellulose bottle from the shaped cellulose blank structure.

Advantages with these features are that the bottle forming unit is enabling an efficient cellulose bottle production process, where cellulose bottles with high quality can be produced at high speeds. The handling of the air-formed cellulose blank structure is simplified through use of the shaped cellulose blank structure having the tube-like configuration, and the first forming mould is used for efficiently producing bottles with high finish at increased production rates. In this way, a more efficient bottle forming unit for producing high-quality cellulose bottles is achieved. The simultaneous forming of the semi-closed bottom portion of the cellulose and the neck portion of a directly preceding cellulose bottle from is providing a unique and fast forming operation.

In one embodiment, the first forming mould comprises openable and closable first mould parts arranged around a pressure lance. A first forming cavity is formed between the first mould parts and the pressure lance, and the feeding unit is configured for feeding the shaped cellulose blank structure around the pressure lance and through the first mould parts when the first mould parts are open. The first mould parts are when closed configured for pressing the shaped cellulose blank structure against the pressure lance for simultaneously forming the neck portion and the semiclosed bottom portion in the first forming cavity. In this way, a section of the pressure lance extending through the first forming cavity is forming part of the first forming mould, and the section of the pressure lance is used for an efficient forming of the neck portion and the semi-closed bottom portion in the first forming cavity. During the pressing operation, a first forming pressure and a first forming temperature are applied onto a part of the shaped cellulose blank structure used for forming the neck portion in the first forming cavity, for an efficient forming operation in the first forming mould.

In one embodiment, the bottle forming unit further comprises a second forming mould. The feeding unit is configured for feeding a formed semi-closed bottom portion and an intermediate section of the shaped cellulose blank structure between the formed semi-closed bottom portion and a directly following formed trailing neck portion to the second forming mould. The second forming mould is configured for forming the midportion from the intermediate section and forming the closed bottom portion from the semi-closed bottom portion. The second forming mould is in this way used for an efficient forming of the mid-portion of the cellulose bottle from the intermediate section and forming the closed bottom portion of the cellulose bottle from the semi-closed bottom portion after the forming operations in the first forming mould

In one embodiment, the second forming mould comprises openable and closable second mould parts forming a second forming cavity. A flexible membrane connected to and arranged in fluid communication with the pressure lance is arranged in the second forming cavity. The feeding unit is configured for feeding the semi-closed bottom portion and the intermediate section around the pressure lance into the second forming mould when the first mould parts and the second mould parts are open. The second mould parts together with the flexible membrane, when the second mould parts are closed around the semi-closed bottom portion and the intermediate section, are configured for forming the closed bottom portion and the mid-portion by inflating the flexible membrane with a pressure medium entering from the pressure lance, where the semi-closed bottom portion and the intermediate section are pressed against the second mould parts by means of the inflated flexible membrane. In this way, the flexible membrane when inflated by the pressure medium is applying a second forming pressure onto the intermediate section and the semi-closed bottom portion. Further, the applied second forming pressure together with an applied second forming temperature onto the semi-closed bottom portion and the intermediate section are efficiently forming the closed bottom portion and the mid-portion of the cellulose bottle.

In one embodiment, the pressure lance is extending to or partly into the second forming cavity. The pressure lance is with these configurations efficiently providing the pressure medium to the flexible membrane arranged within the second forming cavity for inflating or deflating the flexible membrane in the forming operation process.

In one embodiment, the bottle forming unit comprises a fluid control device. The pressure lance is at a first end arranged in fluid communication with the fluid control device, and the pressure lance is at a second end arranged in fluid communication with the flexible membrane. The fluid control device is configured for inflating the flexible membrane with the pressure medium via the pressure lance upon forming the cellulose bottles in the second forming mould. The fluid control device is further arranged for deflating the flexible membrane via the pressure lance after the forming operation in the second forming mould. The fluid control device may have any suitable configuration, and may comprise hydraulic or pneumatic cylinders, fluid pumps, compressors, or other pressure establishing devices for delivering pressurized pressure medium to the flexible membrane via the pressure lance.

In one embodiment, the bottle forming unit further comprises a cutting device arranged in the second mould part or in connection to the second mould part. The cutting device is configured for cutting off the formed neck portion of a leading cellulose bottle from the semi-closed bottom portion of a directly following trailing cellulose bottle by means of the cutting device during the forming of the cellulose bottle in the second forming mould. The cutting device may be arranged with cutting edges on the outer second mould part and the inner second mould part respectively for an efficient cutting operation, where the cutting edges are cutting off the formed neck portion of the leading cellulose bottle from the semi-closed bottom portion of the directly following trailing cellulose bottle upon closing of the second forming mould.

In one embodiment, the first forming mould comprises a thread forming section configured for forming a threaded section of the neck portion upon forming of the neck portion in the first forming mould. The thread forming section comprises a threaded pattern for efficient forming of the threaded section of the neck portion in the first forming mould.

The disclosure further concerns a dry-formed cellulose bottle. The cellulose bottle has an extension in a longitudinal direction and comprises a neck portion, a closed bottom portion, and a mid-portion arranged in the longitudinal direction between the closed bottom portion and the neck portion. The mid-portion is arranged in fluid communication with the neck portion, and the cellulose bottle comprises a compressed seam section. The seam section is extending along the cellulose bottle through the neck portion, the mid-portion, and the closed bottom portion. The seam section is resulting from an overlapping tube-like configuration of the shaped cellulose blank structure when arranged in the forming moulds. The overlapping tube-like configuration is securing that the shaped cellulose blank structure is formed without any gaps or open passages in the feeding direction. The seam section is providing a rigid structural part of the cellulose bottle, and with the overlapping configuration resulting in the seam section the cellulose bottle can be formed without any residual parts of the cellulose blank structure after forming the cellulose bottle in the forming moulds.

In one embodiment, the seam section is extending in the longitudinal direction of the cellulose bottle, or extending essentially in the longitudinal direction of the cellulose bottle. The extension of the seam section is mainly determined by the overlapping tube-like configuration of the shaped cellulose blank structure, and the extension along the cellulose bottle is providing a rigid structural part along the length of the cellulose bottle.

In one embodiment, the seam section of the neck portion has a higher basis weight compared to at least adjacent parts of the neck portion outside the seam section, the seam section of the mid-portion has a higher basis weight compared to at least adjacent parts of the mid-portion outside the seam section, wherein the seam section of the closed bottom portion has a higher basis weight compared to at least adjacent parts of the closed bottom portion outside the seam section. The higher basis weight is resulting from the accumulation of material in the overlapping tube-like configuration of the shaped cellulose blank structure, and the higher basis weight is used for providing the rigid structural part of the cellulose bottle formed by the seam section.

In one embodiment, the neck portion comprises a smooth inner surface and an outer surface arranged with a threaded section. The smooth inner surface is securing a surface structure suitable for preventing bacterial growth and for adding barrier structures, such as plastic films or additives. The threaded section is enabling use of caps for closing the cellulose bottle. In one embodiment, the cellulose bottle comprises a shaped air-formed cellulose blank structure.

In one embodiment, the closed bottom portion comprises a centrally arranged closed collar section of compressed cellulose fibres. The centrally closed collar section is resulting from the forming process and is providing a rigid bottom structure of the cellulose bottle.

In one embodiment, the closed collar section is positioned at a distance above one or more lowest parts of the closed bottom portion in the longitudinal direction. With this configuration, the one or more lowest parts of the cellulose bottle can be used for providing a stable bottom structure of the cellulose bottle, where the bottom structure suitably has an inwardly curved surface configuration. The cellulose bottle has with this construction a high stability when placed on an object surface, such as for example a table surface or other surface.

In one embodiment, the neck portion has a higher average basis weight compared to the mid-portion, and the closed bottom portion has a higher average basis weight compared to the mid-portion. This configuration is providing high rigidity in the neck portion and the closed bottom portion. The higher average basis weight results from a higher amount of fibres per unit area in a certain section of the cellulose bottle compared to another comparable section of the cellulose bottle. In the example embodiment where the cellulose blank structure has the same width and thickness when formed into the tube-like configuration and fed to the first and second forming moulds, and the neck portion has a smaller diameter than the mid-portion, then the same amount fibres are packed into a smaller unit area in the neck portion than in a comparable section of the mid-portion.

BRIEF DESCRIPTION OF DRAWINGS

The disclosure will be described in detail in the following, with reference to the attached drawings, in which

Fig. 1 shows schematically, in a perspective view, a bottle forming unit with a first forming mould and a second forming mould, Fig. 2a-f show schematically, in a perspective view from above and a perspective view from below, a cellulose bottle formed in the bottle forming unit; and in side views and in a perspective view, a shaped cellulose blank structure in different forming steps,

Fig. 3a-e show schematically, in perspective views from above, the first forming mould in different operational steps,

Fig. 4a-e show schematically, in side views, the second forming mould in different operational steps,

Fig. 5a-f show schematically, in perspective views, the bottle forming unit with the first forming mould and the second forming mould in different operational steps,

Fig. 6 shows schematically in a perspective view a transporting unit for transportation of formed cellulose bottles away from the second forming mould, and

Fig. 7 shows schematically, in a perspective view from below, a cellulose bottle comprising a seam section formed in the bottle forming unit.

DESCRIPTION OF EXAMPLE EMBODIMENTS

Various aspects of the disclosure will hereinafter be described in conjunction with the appended drawings to illustrate and not to limit the disclosure, wherein like designations denote like elements, and variations of the described aspects are not restricted to the specifically shown embodiments, but are applicable on other variations of the disclosure.

Figure 1 schematically shows a bottle forming unit II for dry-forming a cellulose bottle 1 from an air-formed cellulose blank structure 2. The bottle forming unit II comprises a feeding unit F, a shaping unit S, a first forming mould M1 , and a second forming mould M2. The bottle forming unit II is arranged for dry-forming the cellulose bottle 1 from the cellulose blank structure 2 in different operational steps in the first forming mould M1 and the second forming mould M2 for an efficient bottle forming process. In the embodiment illustrated in figure 1 , the first forming mould M1 is positioned above the second forming mould M2, and the first forming mould M1 is in this way arranged upstream the second forming mould M2. It should however be understood that the bottle forming unit II in other non-illustrated embodiments may be positioned in other ways, where the first forming mould M1 is arranged upstream the second forming mould M2.

With an air-formed cellulose blank structure 2 is meant an essentially air-formed fibrous web structure produced from cellulose fibres. The cellulose fibres may originate from a suitable cellulose raw material, such as a pulp material. Suitable pulp materials are for example fluff pulp, paper structures, or other cellulose fibrecontaining structures. With air-forming of the cellulose blank structure 2 is meant the formation of a cellulose blank structure in a dry-forming process in which the cellulose fibres are air-formed to produce the cellulose blank structure 2. When air-forming the cellulose blank structure 2 in the air-forming process, the cellulose fibres are carried and formed to the fibre blank structure 2 by air as carrying medium. This is different from a normal papermaking process or a traditional wet-forming process, where water is used as carrying medium for the cellulose fibres when forming the paper or fibre structure. In the air-forming process, small amounts of water or other substances may if desired be added to the cellulose fibres in order to change the properties of the cellulose bottles, but air is still used as carrying medium in the forming process. The cellulose blank structure 2 may, if suitable have a dryness that is mainly corresponding to the ambient humidity in the atmosphere surrounding the air-formed cellulose blank structure 2. As an alternative, the dryness of the cellulose blank structure 2 can be controlled in order to have a suitable dryness level when forming the cellulose bottles 1.

The cellulose blank structure 2 may have a composition where the fibres are of the same origin or alternatively contain a mix of two or more types of cellulose fibres, depending on the desired properties of the cellulose bottles 1. The cellulose fibres used in the cellulose blank structure 2 are during the forming process of the cellulose bottles 1 strongly bonded to each other with hydrogen bonds. The cellulose fibres may be mixed with other substances or compounds to a certain amount as will be further described below. With cellulose fibres is meant any type of cellulose fibres, such as natural cellulose fibres or manufactured cellulose fibres. The cellulose blank structure 2 may specifically comprise at least 95% cellulose fibres, or more specifically at least 99% cellulose fibres. However, the cellulose blank structure 2 may have other suitable configurations and cellulose fibre amounts.

The air-formed cellulose blank structure 2 may have a single-layer or a multi-layer configuration. A cellulose blank structure 2 having a single-layer configuration is referring to a structure that is formed of one layer containing cellulose fibres. A cellulose blank structure 2 having a multi-layer configuration is referring to a structure that is formed of two or more layers comprising cellulose fibres, where the layers may have the same or different compositions or configurations.

One or more reinforcement layers comprising cellulose fibres may be added to the cellulose blank structure 2. The one or more reinforcement layers may be arranged as carrying layers for the cellulose blank structure 2. The reinforcement layer may have a higher tensile strength than the cellulose blank structure 2. This is useful when one or more air-formed layers of the cellulose blank structure 2 have compositions with low tensile strength in order to avoid that the cellulose blank structure 2 will break during the forming of the cellulose bottles 1. The reinforcement layer with a higher tensile strength acts in this way as a supporting structure for the cellulose blank structure 2. The reinforcement layer may be of a different composition than the cellulose blank structure 2, such as for example a tissue layer containing cellulose fibres, an airlaid structure comprising cellulose fibres, or other suitable layer structures. It is thus not necessary that the reinforcement layer is air-formed. The one or more reinforcement layers may be provided with graphical elements or patterns for enabling aesthetically attractive cellulose bottles 1.

The cellulose blank structure 2 may further comprise or be arranged in connection to one or more barrier layers giving the cellulose bottles 1 the ability to hold or withstand liquids, such as for example when the cellulose bottles 1 are used in contact with beverages, food, and other water-containing substances. The one or more barrier layers may be of a different composition than the rest of the cellulose blank structure 2, such as for example a tissue barrier structure or a plastic film structure. The cellulose blank structure 2 may further comprise additives for achieving desired properties of the cellulose bottles 1. The one or more barrier layers may also be applied to the outside of the cellulose bottles 1 , and the one or more barrier layers may be provided with graphical elements or patterns for enabling aesthetically attractive cellulose bottles 1.

The one or more air-formed layers of the cellulose blank structure 2 are fluffy and airy structures, where the cellulose fibres forming the structures are arranged relatively loosely in relation to each other. The fluffy cellulose blank structures 2 are used for an efficient forming of the cellulose bottles 1 , allowing the cellulose fibres to form the cellulose bottles 1 in an efficient way during the forming process.

The shaping unit S is configured for shaping the dry-formed cellulose blank structure 2. This shaping of the cellulose blank structure 2 in the shaping unit S is enabling efficient transportation of the cellulose blank structure 2 and forming of the cellulose bottles 1 in the first forming mould M1 and the second forming mould M2. In the shaping unit S, the cellulose blank structure 2 is shaped into a shaped cellulose blank structure 2s having a tube-like configuration with an inner surface 2a and an outer surface 2b. The cellulose blank structure 2 is provided to the bottle forming unit II in a flat shape, or essentially flat shape as understood from figure 1 .

The cellulose blank structure 2 is transported to the feeding unit F for further transportation of the cellulose blank structure 2 to the shaping unit S and the forming moulds, and in the illustrated embodiment, the feeding unit F comprises a pair of feeding rollers. The feeding unit F is configured for feeding the shaped cellulose blank structure 2s to the first forming mould M1 and the second forming mould M2. The feeding unit is further arranged to stop the feeding of the shaped cellulose blank structure 2s upon forming in the respective forming moulds. It should however be understood that the feeding unit F may have any suitable configuration, such as conveyor belts or other transporting means. The feeding unit F may further be arranged with non-illustrated feeding rollers, feeding belts, or other transportation means arranged in connection to the first forming mould M1 and/or the second forming mould M2, for an efficient feeding, pulling and/or pushing of the shaped cellulose blank structure 2s through the bottle forming unit II. The feeding rollers, feeding belts, or other transportation means, may be arranged before and/or after the first forming mould M1 and/or the second forming mould M2, and provided with suitable gripping means for feeding, pulling and/or pushing the shaped cellulose blank structure 2s. The construction and layout of the feeding unit F may for example vary depending on the design of the bottle forming unit II, the size and design of the cellulose bottles 1 produced, and materials used in the cellulose blank structure 2.

In the illustrated embodiment, the shaping unit S comprises a plurality of deflecting rollers 8 for shaping the dry-formed cellulose blank structure 2 into the shaped cellulose blank structure 2s. The deflecting rollers 8 are shaping the cellulose blank structure 2 upon feeding in a feeding direction DF through a deflecting movement of the cellulose blank structure 2 enabled by the deflecting rollers 8. When passing through the shaping unit S in the feeding direction DF, the cellulose blank structure 2 is shaped into the shaped cellulose blank structure 2s with the tube-like configuration by the deflecting rollers 8, as understood from figure 1. The formed shaped cellulose blank structure 2s is suitably having an overlapping tube-like configuration O that is securing that the shaped cellulose blank structure 2s is formed without any gaps or open passages in the feeding direction DF. When being shaped, opposite side edges 2c of the cellulose blank structure 2 are overlapping each other in the shaped cellulose blank structure 2s. The shaping unit S may in other non-illustrated embodiments be arranged with deflecting plates or similar arrangements instead of the deflecting rollers 8, or alternatively arranged with a combination of deflecting plates and deflecting rollers.

A dry-formed cellulose bottle 1 is schematically shown in figures 2a-b and 7. The cellulose bottle 1 has an extension in a longitudinal direction DLO and comprises a neck portion 1a, a closed bottom portion 1c, and a mid-portion 1b arranged in the longitudinal direction between the closed bottom portion 1c and the neck portion 1a. When the cellulose bottle 1 is arranged in the position shown in figures 2a-b and 7, the mid-portion 1b is arranged above the closed bottom portion 1c and the neck portion 1a is arranged above the mid-portion 1 b. In the following, when it is referred to relative positions of the cellulose bottle 1 when formed or upon forming, expressions such as above are referring to the positioning of the cellulose bottle 1 illustrated in figures 2a-b and 7, where the cellulose bottle 1 is arranged for being placed on a surface in a standing position. The mid-portion 1b is arranged in fluid communication with the neck portion 1a, and the neck portion 1a is provided with a flow opening 1ao. The neck portion 1a suitably comprises a threaded section 1d for a secure attachment of a non-illustrated threaded cap. The dry-formed cellulose bottle 1 is arranged as a rigid self-sustained cellulose-based bottle structure comprising compressed air-formed cellulose fibres. The neck portion 1a is in a conventional manner arranged with a through channel for transportation of liquids out from the cellulose bottle 1 via the flow opening 1ao. The closed bottom portion 1c and the mid-portion 1 b are together forming a liquid holding space, and the mid-portion 1b has a hollow configuration.

The cellulose bottle 1 further comprises a compressed seam section 1e, as shown in figure 7. The seam section 1e is in the illustrated embodiment extending along the cellulose bottle 1 through the neck portion 1a, the mid-portion 1b and the closed bottom portion. The seam section is resulting from the overlapping tube-like configuration O of the shaped cellulose blank structure 2s when arranged in the forming moulds. The overlapping tube-like configuration O of the shaped cellulose blank structure 2s is securing that the cellulose bottle 1 is formed without any gaps or open passages. The seam section 1e is providing a rigid structural part of the cellulose bottle 1 , and with the overlapping configuration resulting in the seam section 1e the cellulose bottle 1 can be formed without any residual parts of the cellulose blank structure 2 after forming of the cellulose bottle 1 in the first forming mould M1 and the second forming mould M2.

The seam section 1e is in the illustrated embodiment extending in the longitudinal direction of the cellulose bottle, or essentially in the longitudinal direction of the cellulose bottle, as shown in figure 7. The extension of the seam section is mainly determined by the overlapping tube-like configuration O of the shaped cellulose blank structure 2s, and the extension of the seam section 1e along the cellulose bottle 1 is providing a rigid structural part along the length of the cellulose bottle 1. The seam section 1e of the neck portion 1a has a higher basis weight compared to at least adjacent parts of the neck portion 1a outside the seam section 1e. The seam section 1 e of the mid-portion 1 b has a higher basis weight compared to at least adjacent parts of the mid-portion 1b outside the seam section 1e. The seam section 1e of the closed bottom portion 1c has a higher basis weight compared to at least adjacent parts of the closed bottom portion 1c outside the seam section 1e. The higher basis weight is resulting from the accumulation of material in the overlapping tube-like configuration O of the shaped cellulose blank structure 2S when forming the cellulose bottle 1. The higher basis weight is used for providing the rigid structural part of the cellulose bottle formed by the seam section 1e.

The neck portion 1a comprises a smooth inner surface 1 ai and an outer surface 1aou arranged with the threaded section. The smooth inner surface 1ai is securing a surface structure suitable for preventing bacterial growth and for adding barrier structures, such as plastic films or additives. The threaded section 1d is enabling use of caps for closing the cellulose bottle 1 .

As will be further described below, the closed bottom portion 1c comprises a centrally arranged closed collar section 1cc of compressed cellulose fibres. The centrally closed collar section 1 Cc is resulting from the bottle forming process in the first forming mould ml and the second forming mould M2 and is providing a rigid bottom structure of the cellulose bottle 1.

The closed collar section 1cc is positioned at a distance above one or more lowest parts 1 CL of the closed bottom portion 1c in the longitudinal direction, as understood from for example figure 7. With this configuration, the one or more lowest parts 1 CL. of the cellulose bottle 1 can be used for providing a stable bottom structure of the cellulose bottle 1 , where the bottom structure suitably has an inwardly curved surface configuration. The cellulose bottle 1 has with this construction a high stability when placed on an object surface, such as for example a table surface or other surface. In the embodiment illustrated in figure 7, the cellulose bottle 1 is arranged with several lowest parts 1 CL. for a high stability.

The neck portion 1a has a higher average basis weight compared to the mid-portion 1 b, and the closed bottom portion 1c has a higher average basis weight compared to the mid-portion 1 b. This configuration is providing high rigidity in the neck portion and the closed bottom portion, and is resulting from the bottle forming process where different parts of the shaped cellulose blank structure 2s are radially compressed to different degrees, as will be understood from the details of the bottle forming process described below.

The cellulose bottle 1 is formed in different forming steps in the first forming mould M1 and the second forming mould M2. The first forming mould M1 is used for forming the neck portion 1a of the cellulose bottle 1 , and partly forming the closed bottom portion 1c of the cellulose bottle 1 into a semi-closed bottom portion 1cs. The second forming mould M2 is used for forming the mid-portion 1b of the cellulose bottle 1 and forming the closed bottom portion 1c from the semi-closed bottom portion 1cs. Upon forming of the semi-closed bottom portion 1cs in the first forming mould, a collar section 1cc of the semi-closed bottom portion 1cs is established by forces acting on the shaped cellulose blank structure 2s.

Each individual cellulose bottle 1 is formed in main sequential forming steps in the first forming mould M1 and the second forming mould M2. The semi-closed bottom portion 1cs is formed in a first sequential forming step in the first forming mould M1 , the neck portion 1a is formed in a second sequential forming step in the first forming mould M 1 , and the mid-portion 1 b together with the closed bottom portion 1 c is formed in a third sequential forming step in the second forming mould M2, as will be further described below.

The first forming mould M1 has a dual configuration for simultaneous forming of a neck portion 1a and a semi-closed bottom portion 1cs, and as understood from the illustrated configuration of the bottle forming unit U, the simultaneous forming in the first forming mould M1 is resulting in the forming of a neck portion 1a and a semiclosed bottom portion 1cs of different bottles. In this way, the first forming mould M1 is configured for forming a neck portion 1a of a leading cellulose bottle 1 L simultaneously with forming a semi-closed bottom portion 1cs of a directly following trailing cellulose bottle 1T from the shaped cellulose blank structure 2s, as will be further described below.

The first forming mould M1 is schematically illustrated in figures 3a-e. In figures 3a-e, the shaped cellulose blank structure 2s is sectioned for illustrative purposes, where only a part of the shaped cellulose blank structure 2s is shown. The first forming mould M1 comprises openable and closable first mould parts 3a, 3b arranged around a pressure lance 5. An outer first mould part 3a is movably arranged relative to the pressure lance 5 as indicated with the arrow in figure 3a. The outer first mould part 3a is suitably displaceable in reciprocating linear movements towards and away from the pressure lance 5. An inner first mould part 3b comprises clamping arm sections pivotably arranged relative to each other around a pivoting axis A, as indicated with arrows in figure 3a. The inner first mould part 3b is extending partly around the pressure lance 5. The inner first mould part 3a is suitably displaceable in pivoting movements around the pivoting axis A towards and away from the pressure lance 5. In figure 3a, the first forming mould M1 is arranged in an open state So, where the first mould parts 3a, 3b have been displaced away from the pressure lance, allowing the shaped cellulose blank structure 2s to be fed around the pressure lance 5 and through the first mould parts 3a, 3b, as shown in figure 3b.

The first forming mould M1 comprises a first forming cavity C1 formed between the first mould parts 3a, 3b and the pressure lance 5, as shown in figures 3a-e. The feeding unit F is feeding the shaped cellulose blank structure 2s around the pressure lance 5 and through the first mould parts 3a, 3b when the first mould parts 3a, 3b are arranged in the open state So. When the shaped cellulose blank structure 2s is arranged in the position shown in figure 3b, where the shaped cellulose blank structure 2s is positioned between the pressure lance 5 and the first mould parts 3a, 3b, the first mould parts may be displaced towards the pressure lance 5, as indicated with arrows in figure 3c. Suitably, the inner first mould part 3b is pivoted towards the pressure lance 5 in a movement faster than the displacement of the outer first mould part 3b for an efficient forming process. When the inner first mould part 3b is closed, as shown in figure 3c, the outer first mould part 3a may be further pushed towards the pressure lance 5 with a suitable pushing force Fp to a closed state Sc of the first forming mould M1 , as indicated with the arrow in figure 3d. When closed, the first mould parts 3a, 3b are pressing the shaped cellulose blank structure 2s radially against the pressure lance 5 for simultaneously forming the neck portion 1a and the semi-closed bottom portion 1cs in the first forming cavity C1. During the pressing operation, a first forming pressure P _Fi and a first forming temperature TFI are at least applied onto the part of the shaped cellulose blank structure 2s used for forming the neck portion 1a in the first forming cavity C1. After the forming operation the first forming mould M1 is returned to the open state So, as shown in figure 3e. In figure 3e, the formed neck portion 1a and the semi-closed bottom portion 1cs with the collar section 1cc is schematically shown, where the collar section 1cc is the most narrow portion of the semi-closed bottom portion 1cs that is transitioning towards the neck portion 1a. As understood from the figure, the collar section 1cc has a collar opening 1co that is corresponding to the flow opening 1ao of the neck portion 1a.

The first forming mould M1 suitably comprises a thread forming section 3c, as shown in for example figure 3a. The thread forming section 3c is forming the threaded section 1 d of the neck portion 1 a upon forming of the neck portion 1 a in the first forming mould M1. The thread forming section is arranged with a threaded pattern for efficient forming of threads of the threaded section on the outside surface of the neck portion 1a in the first forming mould, as understood from the figures.

The applied second forming pressure PF2 is suitably in the range of 1-100 MPa, preferably 4-20 MPa, and the applied second forming temperature TF2 is suitably in the range of 100-300 °C, preferably 100-200 °C.

The first mould parts 3a, 3b of the first forming mould M1 are suitably arranged as stiff mould parts. With stiff mould parts is meant that the mould parts are made of a stiff material with limited deformation capabilities, such as for example steel, aluminium, composite materials or a combination of different materials. The section of the pressure lance 5 extending through the first forming mould M1 is suitably made of a stiff material with limited deformation capabilities, such as for example steel, aluminium, composite materials or a combination of different materials. This section of the pressure lance 6 may be stiffer than the other parts of the pressure lance 6 to withstand the high forming pressure in the first forming mould M1. In one embodiment, the section of the pressure lance 5 extending through the first forming mould M1 is reinforced with an outer structural piece of material surrounding the pressure lance 5, establishing a strong structural part around the pressure lance 5.

The first mould part M1 may further comprise a heating unit. The heating unit is configured for applying the first forming temperature TFI onto the shaped cellulose blank structure 2s in the first forming cavity C1 during the forming operation in the first forming mould M1. The heating unit may have any suitable configuration. The heating unit may be integrated in or cast into the first mould parts 3a, 3b, and suitable heating devices are e.g. electrical heaters, such as resistor elements, or fluid heaters. Other suitable heat sources may also be used.

The shaped cellulose blank structure 2s may in other non-illustrated embodiments be pre-shaped into an hourglass-shape before being inserted into the first forming mould M1 for facilitating the forming operation in the first forming mould M1. Suitable shaping elements may be used for delimiting the radial extension of sections of the pre-shaped cellulose blank structure 2s for enabling the hourglass shape. The shaping elements may for example be arranged as a snare structure or snare-like element arranged around the shaped cellulose blank structure 2s upstream the first forming mould M1 , where the snare structure or snare-like element upon constriction is delimiting the radial extension of a section of the shaped cellulose blank structure 2s. After preshaping, the snare structure or snare-like element is returning to a non-constricted state for feeding of the pre-shaped section of the shaped cellulose blank structure 2s to the first forming mould M 1.

As described above, each individual cellulose bottle 1 is formed in sequential steps in the first forming mould M1 and the second forming mould M2. When the semi-closed bottom portion 1cs and the neck portion 1a for an individual bottle 1 have been formed in the first sequential and second sequential forming steps in the first forming mould M1 , the semi-closed bottom portion 1cs and the neck portion 1a together with an intermediate section SINT of the shaped cellulose blank structure 2s between the formed semi-closed bottom portionics and the neck portion 1a is transported to the second forming mould M2. The mid-portion 1 b together with the closed bottom portion is formed in a third sequential forming step in the second forming mould M2, as will be further described below.

A shaped cellulose blank structure 2s is schematically shown in figure 2c. The shaped cellulose blank structure 2s is during the forming operation transported in the feeding direction DF through the first forming mould M1 and thereafter through the second forming mould M2. In figure 2c, the shaped cellulose blank structure 2s is divided in a first section S1 , an intermediate section SINT, and a second section S2, as illustrated in figure 2d, where the different sections are used for forming different parts of each cellulose bottle 1. In the first sequential forming step, the first section S1 is fed to the first forming mould M1. The first section S1 of the shaped cellulose blank structure 2S is used for forming the semi-closed portion 1cs of the cellulose bottle 1 simultaneously with forming the neck portion 1a of a directly preceding cellulose bottle 1 P, as understood from figure 2e. Thereafter, in the second sequential forming step, the following second section S2 arranged at a distance from the first section S1 is fed to the first forming mould M1. The second section S2 of the shaped cellulose blank structure 2S is used for forming the neck portion 1a of the cellulose bottle 1 simultaneously with forming the semi-closed portion 1cs of a directly following cellulose bottle 1 F, as understood from figure 2e. The part of the shaped cellulose blank structure 2S shown in figure 2e is illustrating the configuration after the two sequential forming steps of forming operations in the first forming mould M1. As understood from figure 2e, the intermediate section SINT has not yet been shaped or formed in a forming mould after the two sequential steps of forming operations in the first forming mould M1. As described above, upon forming of the semi-closed bottom portion 1cs in the first forming mould, the collar section 1cc of the semi-closed bottom portion 1cs is established by forces acting on the shaped cellulose blank structure 2s. The collar section 1cc is defined as the most narrow portion of the semi-closed bottom portion 1cs that is transitioning towards the neck portion 1a, as for example shown in figure 2e.

A row of cellulose bottles 1 are produced after each other from the shaped cellulose blank structure 2s, as understood from for example figure 2e. As indicated in figure 2e, consecutive cellulose bottles can be formed from the shaped cellulose blank structure 2S, which in the figure has been pre-shaped in the first forming mould M1 as described above. In figure 2f, the relationship between following cellulose bottles is illustrated, where a leading cellulose bottle 1 L is directly followed by a trailing cellulose bottle 1T. The expressions leading and trailing are in this respect referring to the feeding direction DF, and a leading cellulose bottle 1 L is thus formed before a trailing cellulose bottle 1T in the first and second forming moulds. If referring to figures 2e-f, the preceding cellulose bottle 1P illustrated in figure 2e is a leading cellulose bottle 1 L relative to the directly succeeding cellulose bottle 1 , and the cellulose bottle 1 is a trailing bottle relative to the preceding cellulose bottle 1 P. If again referring to figures 2e-f, the cellulose bottle 1 illustrated in figure 2e is a leading cellulose bottle 1 L relative to the directly succeeding following cellulose bottle 1 F, and the following cellulose bottle 1 F is a trailing bottle relative to the cellulose bottle 1. The expressions above will be used in the following to define relationships in the cellulose bottle forming flow.

The second forming mould M2 is schematically illustrated in figures 4a-e. The second forming mould M2 comprises openable and closable second mould parts 4a, 4b forming a second forming cavity C2. A flexible membrane 6 is arranged in the second forming cavity C2, and the flexible membrane 6 is connected to and arranged in fluid communication with the pressure lance 5. The pressure lance 5 is suitably extending to or partly into the second forming cavity C2. An outer second mould part 4a and an inner second mould part 4b are movably arranged relative to each other and relative to the flexible membrane 6, as indicated with the double arrows in figures 1 and 4a. The outer second mould part 4a is suitably displaceable in reciprocating linear movements towards and away from the inner second mould part 4b and the flexible membrane 6. The inner second mould part 4b is suitably displaceable in reciprocating linear movements towards and away from the outer second mould part 4a and the flexible membrane 6. In figure 4a, the second forming mould M2 is arranged in an open state So, where the outer second mould part 4a and the inner second mould part 4b have been displaced in directions away from each other and away from the flexible membrane 6, allowing the shaped cellulose blank structure 2s to be fed around the flexible membrane 6 and received between the second mould parts 4a, 4b, as shown in figure 4a. In other non-illustrated embodiments, one of the outer second mould part 4a and the inner second mould part 4b may be arranged as a stationary mould part, where the other mould part is movably arranged.

The second forming mould M2 is forming the mid-portion 1b of the cellulose bottle 1 from the intermediate section SINT, and the closed bottom portion 1c of the cellulose bottle 1 from the semi-closed bottom portion 1cs in the second forming cavity C2. The feeding unit F is feeding the formed semi-closed bottom portion 1cs, the intermediate section SINT, and the formed neck portion 1a around the pressure lance 5 in the feeding direction DF from the first forming mould M1 towards the second forming mould M2 when the first mould parts 3a, 3b and the second mould parts 4a, 4b are arranged in open states So. The feeding unit F is in this way feeding the formed semiclosed bottom portion 1cs and the intermediate section SINT of the shaped cellulose blank structure 2s between the formed semi-closed bottom portion 1cs and a directly following formed trailing neck portion 1aT to the second forming mould M2, as shown in figure 4a.

When the semi-closed bottom portion 1cs and the intermediate section SINT is arranged in the position shown in figure 4a, and thus positioned between the outer second mould part 4a and the inner second mould part 4b, with the flexible membrane 6 arranged inside the shaped cellulose blank structure 2s, the outer second mould part 4a and the inner second mould part 4b are displaced towards each other for arranging the second forming mould M2 into a closed state Sc, as shown in figures 4b-c. Upon displacement of the outer second mould part 4a and the inner second mould part 4b towards each other, the mould parts are pushing the semi-closed bottom portion 1cs towards a closed configuration, as shown in figures 4b-c and illustrated more in detail in figure 4e. The outer second mould part 4a and the inner second mould part 4b are gripping the collar section 1cc of the semi-closed bottom portion 1cs when moved towards each other for an efficient forming process. In this way, the collar opening 1co of the semi-closed bottom portion 1cs is closed by the forces exerted by the second mould parts 4a, 4b.

The movements of the outer second mould part 4a and the inner second mould part 4b towards the closed state Sc are indicated with arrows in figure 4b. The outer second mould part 4a and the inner second mould part 4b are in this way pushed towards each other for closing the second forming mould M2. Upon further movement of the outer second mould part 4a and the inner second mould part 4b the second mould parts are arranged in contact with each other, and the second forming mould M2 is arranged in the closed state Sc, as shown in figure 4c. To secure the closed state Sc of the second forming mould M2 during the forming process, the outer second mould part 4a and the inner second mould part 4b are pushed towards each other with suitable pushing forces FP, as shown in figure 4c. During the movements of the outer second mould part 4a and the inner second mould part 4b, the semi-closed bottom portion 1cs is further closed by the second mould parts, as described above and understood from figures 4b-c.

In the closed state Sc, the second mould parts 4a, 4b together with the flexible membrane 6 are forming the closed bottom portion 1c and the mid-portion 1c of the cellulose bottle 1 by inflating the flexible membrane 6 towards the second mould parts 4a, 4b as understood from figure 4c. The flexible membrane 6 is inflated with a pressure medium P entering from the pressure lance 5, as indicated with the arrow in figure 4c. Thus, when the second mould parts 4a, 4b are closed around the semiclosed bottom portion 1cs and the intermediate section SINT, the further closed semiclosed bottom portion 1cs and the intermediate section SINT are pressed against the second mould parts 4a, 4b by means of the inflated flexible membrane 6 for forming the cellulose bottle 1. In this way, the flexible membrane 6 when inflated by the pressure medium P is applying a second forming pressure PF2 onto the intermediate section SINT and the further closed semi-closed bottom portion 1cs. Further, the applied second forming pressure PF2 together with an applied second forming temperature TF2 onto the further closed semi-closed bottom portion 1cs and the intermediate section SINT are forming the closed bottom portion 1c and the mid-portion 1c of the cellulose bottle 1 into rigid structures.

The bottom of the formed rigid closed bottom portion 1c of the cellulose bottle has an inwardly curved surface configuration, as understood from for example figures 1b, 4c, and 4e. The closed collar section 1cc of the semi-closed bottom portion 1cs is in this way arranged above the lowermost portions of the cellulose bottle 1 , as shown in figure 4e. The inwardly curved surface configuration is enabled by the shape of the second mould parts 4a, 4b and the inflation of the flexible membrane 6 upon forming in the second forming mould M2, where the flexible membrane is pushing the semiclosed bottom portion 1cs towards the second forming moulds 4a, 4b. The inwardly curved surface configuration is providing a stable bottom structure of the cellulose bottle 1. The cellulose bottle 1 has with this construction a high stability when placed on an object surface, such as for example a table surface or other surface.

The already formed upper portion 1a is as understood from figures 4a-e arranged within the second forming mould M2 during the forming operation. It should however be understood that no forming pressure is applied to the upper portion 1a in the second forming mould M2 during the forming of the cellulose bottle 1.

The applied second forming pressure PF2 is suitably in the range of 1-100 MPa, preferably 4-20 MPa, and the applied second forming temperature TF2 is suitably in the range of 100-300 °C, preferably 100-200 °C.

After the forming operation, the second forming mould M2 is returned to the open state So, as shown in figure 4d, for an easy removal of the cellulose bottle 1 and for repeating the forming operation.

The second mould parts 4a, 4b of the second forming mould M2 are suitably arranged as stiff mould parts. With stiff mould parts is meant that the mould parts are made of a stiff material with limited deformation capabilities, such as for example steel, aluminium, composite materials or a combination of different materials.

The second mould part M2 may further comprise a heating unit. The heating unit is configured for applying the second forming temperature TF2 onto the shaped cellulose blank structure 2s and the semi-closed bottom portion 1cs during the forming operation in the second forming mould M2. The heating unit may have any suitable configuration. The heating unit may be integrated in or cast into the second mould parts 4a, 4b, and suitable heating devices are e.g. electrical heaters, such as resistor elements, or fluid heaters. Other suitable heat sources may also be used.

The flexible membrane 6 is made of a material that is allowed to deform when being inflated upon forming of the cellulose bottles 1 in the second forming mould M2. Suitable materials are for elastomeric compositions, such as for example rubber, or other elastomers exhibiting elastic or rubber-like properties. The material used in the flexible membrane 6 suitably withstands high pressure levels from the pressure medium P when being inflated, as well as repeated inflation and deflation cycles.

The pressure medium P is used for establishing the second forming pressure PF2 in the second forming cavity C2 upon inflating the flexible membrane 6. The pressure medium P used in the forming operation in the second forming mould M2 may be a liquid composition or a gas, such as for example oil, water, or air.

The bottle forming unit II comprises a fluid control device D, as schematically indicated in figure 1. The pressure lance 5 is at a first end 5a arranged in fluid communication with the fluid control device D, and the pressure lance 5 is at a second end 5b arranged in fluid communication with the flexible membrane 6. The fluid control device D is configured for inflating the flexible membrane 6 with the pressure medium P via the pressure lance 5 upon forming in the second forming mould M2. The fluid control device D is further arranged for deflating the flexible membrane 6 via the pressure lance 5 after the forming operation in the second forming mould M2. The fluid control device may have any suitable configuration, and may comprise hydraulic or pneumatic cylinders, fluid pumps, compressors, or other pressure establishing devices for delivering pressurized pressure medium to the flexible membrane via the pressure lance 5. The bottle forming unit II may further comprise a control unit for controlling the forming operation.

The bottle forming unit II further comprises a cutting device 7 arranged in the second mould part M2 or in connection to the second mould part M2. In the embodiment illustrated in figures 4a-e, the cutting device 7 is arranged in the second mould part M2. The cutting device 7 may be arranged with cutting edges 7a on the outer second mould part 4a and the inner second mould part 4b respectively as shown in figure 4e. The cutting device 7 is cutting off the formed neck portion 1a of a leading cellulose bottle 1 L from the semi-closed bottom portion 1cs of a directly following trailing cellulose bottle 1T by means of the cutting device 7 upon closing of the second forming mould M2 during the forming operation of the cellulose bottle 1 in the second forming mould M2, as shown in figure 4e. In figure 4e, the second forming mould M2 is illustrated in the closed state before the inflation of the flexible membrane 6 with the pressure medium P, and the cutting operation is suitably completed when the second mould part M2 is closed.

According to the embodiment shown in figures 4a-d, the pressure lance 5 extends into the second forming mould M2. The cutting device 7 may be arranged to work against and around the pressure lance 5 such that the pressure lance 5 acts as an anvil against which the cutting edges 7a are pressed, and the neck portion 1a is in this way separated from the semi-closed bottom portion 1cs accordingly. Here, the pressure lance 5 may comprise a reinforced portion that can withstand the pressure from the cutting edge. The reinforced portion can be arranged as a thicker material portion of the pressure lance 5 and/or can be made from a different material than adjacent portions of the pressure lance 5. As an alternative, the entire pressure lance 5 is made from a suitable material than can withstand pressure, both in the first forming mould M1 and the second forming mould M2. The reinforced portion can alternatively be arranged as a separate piece of material arranged around the pressure lance 5.

The bottle forming unit II may further comprise an auxiliary cutting device 9 arranged in the second mould part M2, as illustrated in figure 4e. The auxiliary cutting device 9 may be arranged with cutting edges 9a on the outer second mould part 4a and the inner second mould part 4b respectively as indicated in figure 4e. The auxiliary cutting device 9 is cutting off residual parts 1 CR of the closed collar section 1cc of the semiclosed bottom portion 1cs that may extend out from the second forming mould M2 when arranged in the closed state Sc.

The dry-forming process of the cellulose bottle 1 will be described below in connection to figures 5a-f. Throughout the dry-forming process, the dry-formed cellulose blank structure 2 is shaped into a shaped cellulose blank structure 2s, where the shaped cellulose blank structure 2s has a tube-like configuration as described above. In figure 5a, the first forming mould M1 is arranged in the open state So and the second forming mould M2 is arranged in the open state So. The position in figure 5a is illustrating a position after the first sequential forming step in the first forming mould M1 and before the second sequential forming step in the first forming mould M1 for forming the cellulose bottle 1. In this position shown in figure 5a, the first section S1 of the shaped cellulose blank structure 2s has already been fed to and further transported from the first forming mould M1 , where the semi-closed bottom portion 1cs of the cellulose bottle 1 together with the neck portion 1a of the directly preceding cellulose bottle 1 P were simultaneously formed from the first section S1 in the first forming mould M1. In the first sequential forming step, the shaped cellulose blank structure 2s was fed around the pressure lance 5 and through the first mould parts 3a, 3b. Thereafter, the feeding of the shaped cellulose blank structure 2s was stopped when the first section S1 of the shaped cellulose blank structure 2s was arranged in a position aligned with the first mould parts 3a, 3b. Then, the first mould parts 3a, 3b were closed and the first section S1 was pressed against the pressure lance 5 by means of the first mould parts 3a, 3b for forming the semi-closed bottom portion 1cs of the cellulose bottle 1 in the first forming cavity C1 , and simultaneously forming the neck portion 1a of the directly preceding cellulose bottle 1P in the first forming cavity C1. Upon forming of the semi-closed bottom portion 1cs of the cellulose bottle 1 in the first forming mould M1 , the first forming pressure P _Fi and the first forming temperature TFI were applied onto at least the part of the first section S1 of the shaped cellulose blank structure 2s used for forming the neck portion 1a of the preceding cellulose bottle 1 P. It should be understood that the first forming pressure P _Fi and the first forming temperature Tn also may be applied to at least a part of the first section S1 used for forming the semi-closed bottom portion 1cs for a more structurally rigid formation of the semi-closed bottom portion 1cs. The first forming pressure P _Fi and the first forming temperature Tn may for example be applied to the established collar section 1cc of the semi-closed bottom portion 1cs.

In the position shown in figure 5a, the following second section S2 of the shaped cellulose blank structure 2s has been fed to the first forming mould M1 , and at the same time the formed neck portion 1a, the intermediate section SINT, and the semiclosed bottom portion 1cs, of the preceding cellulose bottle 1P have been fed to the second forming mould M2. When opening the first mould parts 3a, 3b, the shaped cellulose blank structure 2s was fed around the pressure lance 5 and through the first mould parts 3a, 3b. Thereafter, the feeding of the shaped cellulose blank structure 2s was stopped when the second section S2 of the shaped cellulose blank structure 2s is arranged in a position aligned with the first mould parts 3a, 3b, as understood from figure 5a.

In figure 5b, the first forming mould M1 is arranged in the closed state Sc and the second forming mould M2 is arranged in the closed state Sc. The position of the shaped cellulose blank structure 2s in figure 5b, is illustrating a position in the first forming mould M1 during the second sequential forming step for forming the neck portion 1a of the cellulose bottle 1 and the semi-closed bottom portion 1cs of a directly following cellulose bottle 1 F, and a position in the second forming mould M2 where the preceding bottle 1 P is formed. In this position shown in figure 5b, the neck portion 1a of the cellulose bottle 1 is formed simultaneously with the semi-closed bottom portion 1cs of a directly following cellulose bottle 1 F from the second section S2 in the first forming mould M1. After closing of the first mould parts 3a, 3b, the second section S2 is pressed against the pressure lance 5 by means of the first mould parts 3a, 3b for forming the neck portion 1 a of the cellulose bottle 1 in the first forming cavity C1 , simultaneously with forming the semi-closed bottom portion 1cs of the directly following cellulose bottle 1 F in the first forming cavity C1. Upon forming of the neck portion 1a of the cellulose bottle 1 in the first forming mould M1 , the first forming pressure P _Fi and the first forming temperature TFI are applied onto at least the part of the second section S2 of the shaped cellulose blank structure 2s used for forming a structurally rigid neck portion 1a of the cellulose bottle 1. The threaded section 1d of the neck portion 1a is established by the threaded section 3c upon forming of the neck portion 1a in the first forming mould M1. It should be understood that the first forming pressure P _Fi and the first forming temperature Tn also may be applied to the at least a part of the second section S2 used for forming the semi-closed bottom portion 1cs of the directly following cellulose bottle 1 F for a more structurally rigid formation of the semi-closed bottom portion 1cs. The first forming pressure P _Fi and the first forming temperature Tn may for example be applied to the established collar section 1cc of the semi-closed bottom portion 1cs of the directly following cellulose bottle 1 F.

In figure 5c, the first forming mould M1 and the second forming mould M2 have returned to the open states So. In figure 5c, the formed preceding bottle 1 P can be removed from the second forming mould M2, as indicated with the arrow. Thereafter, the formed semi-closed bottom portion 1cs of the cellulose bottle 1 and an intermediate section SINT of the shaped cellulose blank structure 2s between the formed semi-closed bottom portion 1cs of the cellulose bottle 1 and the formed neck portion 1a of the cellulose bottle 1 is fed to the second forming mould M2, as shown in figure 5d.

In the second forming mould M2, the mid-portion 1b of the cellulose bottle 1 is formed from the intermediate section SINT and the closed bottom portion 1c of the cellulose bottle 1 is formed from the semi-closed bottom portion 1cs. To form the cellulose bottle 1 in the third sequential forming step in the second forming mould M2, the semi-closed bottom portion 1cs and the intermediate section SINT is fed around the pressure lance 5 into the second forming mould M2, as shown in figure 5d. The feeding of the semiclosed bottom portion 1cs and the intermediate section SINT is stopped when positioned between the open second mould parts 4a, 4b, as shown in figure 5d. Thereafter the second mould parts 4a, 4b are closed around the semi-closed bottom portion 1cs and the intermediate section SINT and the flexible membrane 6 is inflated with the pressure medium P entering from the pressure lance 5, as shown in figure 5e. The second forming pressure PF2 is applied onto the semi-closed bottom portion 1cs and the intermediate section SINT by pressing the semi-closed bottom portion 1cs and the intermediate section SINT against the second mould parts 4a, 4b by means of the inflated flexible membrane 6. The second forming temperature TF2 is applied onto the semi-closed bottom portion 1cs and the intermediate section SINT, for forming the closed bottom portion 1c and the mid-portion 1c of the cellulose bottle 1 into rigid structures. The earlier formed neck portion 1a of the cellulose bottle 1 is cut off from the semi-closed bottom portion 1cs of the directly following cellulose bottle 1 F by means of the cutting device 7 during the forming of the cellulose bottle 1 in the second forming mould M2. In figure 5e, the neck portion 1a of the following bottle 1 F is formed in the first forming mould M1 together with the semi-closed bottom portion of a further following cellulose bottle 1 FF. After the forming operation, the flexible membrane 6 is deflated and the second mould parts 4a, 4b are opened for removal of the formed cellulose bottle 1 from the second forming mould M2, as shown in figure 5f. A negative pressure may be applied to the flexible membrane 6 for an efficient deflating operation. In one embodiment, the first mould parts 3a, 3b and the second mould parts 4a, 4b are simultaneously closed. In other embodiments, the first mould parts 3a, 3b and the second mould parts 4a, 4b are non-simultaneously closed.

The bottle forming unit II may further be arranged with a transporting unit T for transportation of formed cellulose bottles 1 away from the second forming mould M2, as shown in figure 6.

It will be appreciated that the above description is merely exemplary in nature and is not intended to limit the present disclosure, its application or uses. While specific examples have been described in the specification and illustrated in the drawings, it will be understood by those of ordinary skill in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the present disclosure as defined in the claims. Furthermore, modifications may be made to adapt a particular situation or material to the teachings of the present disclosure without departing from the essential scope thereof. Therefore, it is intended that the present disclosure not be limited to the particular examples illustrated by the drawings and described in the specification as the best mode presently contemplated for carrying out the teachings of the present disclosure, but that the scope of the present disclosure will include any embodiments falling within the foregoing description and the appended claims. Reference signs mentioned in the claims should not be seen as limiting the extent of the matter protected by the claims, and their sole function is to make claims easier to understand.

REFERENCE SIGNS

1 : Cellulose bottle

1a: Neck portion lar Inner surface

1ao: Flow opening

1 aou: Outer surface

1a-r: Trailing neck portion

1b: Mid-portion

1c: Closed bottom portion

1cc: Collar section

1 CL: Lowest part

1co: Collar opening

1cs: Semi-closed bottom portion

1d: Threaded section

1e: Seam section

1 F: Following cellulose bottle

1 L: Leading cellulose bottle

1P: Preceding cellulose bottle

1 T: Trailing cellulose bottle

2: Cellulose blank structure

2a: Inner surface

2b: Outer surface

2c: Side edge

2s: Shaped cellulose blank structure

3a: Outer first mould part

3b: Inner first mould part

3c: Thread forming section

4a: Outer second mould part

4b: Inner second mould part

5: Pressure lance

5a: First end

5b: Second end

6: Flexible membrane

7: Cutting device 8: Deflecting rollers

9: Auxiliary cutting device

A: Pivoting axis

C1 : First forming cavity

C2: Second forming cavity

D: Fluid control device

F: Feeding unit

Fp: Pushing force

M1: First forming mould

M2: Second forming mould

O: Overlapping tube-like configuration

P: Pressure medium

PF: Forming pressure

S: Shaping unit

S1 : First section

S2: Second section

Sc: Closed state

SINT: Intermediate section

So: Open state

T: Transportation unit

Tp: Forming temperature

II: Bottle forming unit