Method for dry-forming cellulose products from cellulose fibres in a product forming unit and a product forming unit

Abstract

A method for dry-forming a cellulose product from cellulose fibres in a product forming unit and product forming unit, where the product forming unit comprises at least one shaping element and a forming mould. Loose and separated cellulose fibres are provided and the loose and separated cellulose fibres are fed into a flow of air for transporting the cellulose fibres to the at least one shaping element by means of the flow of air as carrying medium for the cellulose fibres; arranging the loose and separated cellulose fibres onto a three-dimensional surface of the at least one shaping element by means of the flow of air for air-forming at least one three-dimensional body of cellulose fibres; dry-forming the cellulose product into a three-dimensional compressed fibre structure by pressing and heating at least one three-dimensional body of cellulose fibres in a forming mould with a forming pressure in the range of 1-600 MPa and with a forming temperature in the range of 60-300 °C

Description

[0001] METHOD FOR DRY-FORMING CELLULOSE PRODUCTS FROM CELLULOSE

[0002] FIBRES IN A PRODUCT FORMING UNIT AND A PRODUCT FORMING UNIT

[0003] TECHNICAL FIELD

[0004] The present disclosure relates to a method for dry-forming cellulose products from cellulose fibres in a product forming unit. The disclosure further relates to a product forming unit for dry-forming cellulose products from cellulose fibres.

[0005] BACKGROUND

[0006] 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 products having a closed bottom portion, such as for example bottles, cups, and containers with a bottom portion.

[0007] Product forming units are used when manufacturing cellulose products 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 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, 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, a cellulose structure air-formed from cellulose fibres is used. The cellulose structure is inserted into a forming mould and during the dry-forming of the cellulose products, the cellulose fibres are subjected to a high forming pressure and a high forming temperature. One difficulty with dry-forming methods is the problem with an efficient production process, where deep drawn cellulose products can be produced at high speeds with high quality. The air-forming and handling of the cellulose structure is a complicated and time consuming process when dry-forming the cellulose products, and there is a need for producing products with high finish at increased production rates. Thus, a more efficient product forming unit and method for producing high-quality cellulose products are desired, especially when forming deep drawn products.

[0008] SUMMARY

[0009] An object of the present disclosure is to provide a method for dry-forming cellulose products from cellulose fibres in a product forming unit and a product forming unit for dry-forming cellulose products from cellulose fibres, 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 cellulose products and the product forming unit for dry-forming cellulose products.

[0010] The disclosure concerns a method for dry-forming a cellulose product from cellulose fibres in a product forming unit. The product forming unit comprises at least one shaping element and a forming mould. The shape of the shaping element corresponds to the shape of the forming mould. The method comprises the steps: providing loose and separated cellulose fibres and feeding the loose and separated cellulose fibres into a flow of air for transporting the cellulose fibres to the at least one shaping element by means of the flow of air as carrying medium for the cellulose fibres; arranging the loose and separated cellulose fibres onto a three-dimensional surface of the at least one shaping element by means of the flow of air for air-forming at least one three- dimensional body of cellulose fibres, where the thickness of the at least one three- dimensional body may be substantially equal over the complete body; feeding the at least one three-dimensional body of cellulose fibres from the shaping element to the forming mould; dry-forming the cellulose product into a three-dimensional compressed fibre structure by pressing and heating at least one three-dimensional body of cellulose fibres in a forming mould with a forming pressure in the range of 1- 600 MPa, preferably in the range of 1-100 MPa, more preferably in the range of 4-20 MPa, and with a forming temperature in the range of 60-300 °C, preferably in the range of 100-200 °C, more preferably in the range of 120-170 °C.

[0011] Advantages with these features are that the process of forming the cellulose products can be more efficient, where cellulose products can be produced at high speeds with high quality by shaping the three-dimensional body of cellulose fibres before dryforming the cellulose product into a three-dimensional compressed fibre structure in the forming mould. The shape of the at least one three-dimensional body corresponds to the shape of the cellulose product formed in the forming mould. The handling of the cellulose fibres is simplified with the at least one three-dimensional body of cellulose fibres, and the method is enabling the dry-forming of cellulose products with high finish at high production rates. In this way, a more efficient product forming unit and method for producing high-quality cellulose products is achieved, which especially is suitable for forming deep drawn products. By giving the three-dimensional body an equal thickness, it is ensured that the cellulose product will meet the required specifications. An equal thickness may be seen as the dimensional height of the cellulose body, or as an equal weight of the cellulose fibres, measured as the GSM (grams per square meter) of the cellulose fibres.

[0012] In one embodiment, the three-dimensional surface is an outer surface of the shaping element. The shaping element further comprises an inner surface opposite the outer surface, and the shaping element comprises a plurality of suction openings connecting the outer surface and the inner surface. The method further comprises the steps: arranging the loose and separated cellulose fibres onto the three-dimensional surface of the shaping element by means of the flow of air for air-forming the three- dimensional body of cellulose fibres, and applying a negative pressure via the suction openings for distributing the cellulose fibres onto the three-dimensional surface. The suction openings are enabling efficient deposition of the cellulose fibres onto the three-dimensional surface, and the negative pressure applied is securing a desired distribution of the cellulose fibres. This will in one example ensure that the thickness of the three-dimensional body is substantially equal over the complete body. The suction openings may have any suitable shape, size and configuration. The shape and / or size of the suction openings may vary between different parts of the shaping element, as well as the number of suction openings arranged in the shaping element. Depending on the geometry of the shaping element, this may in one example ensure that the thickness of the three-dimensional body is substantially equal over the complete body.

[0013] In one embodiment, the shaping element is arranged as a three-dimensional net structure or as a solid perforated structure. These constructions are providing an efficient distribution of cellulose fibres onto the three-dimensional surface, while allowing the flow air to pass through the shaping element.

[0014] In one embodiment, the at least one three-dimensional body of cellulose fibres has a moisture content in the range of 4-15 wt%, preferably in the range of 6-10 wt%, when arranged in the forming mould. These ranges are enabling efficient dry-forming of the cellulose products into the three-dimensional compressed fibre structure by pressing and heating the at least one three-dimensional body of cellulose fibres in the forming mould.

[0015] In one embodiment, the method further comprises the steps: forming the cellulose product into the three-dimensional compressed fibre structure in a single pressing operation by pressing and heating at least one three-dimensional body of cellulose fibres in the forming mould with the forming pressure and the forming temperature. With a single pressing operation is meant that the cellulose product is formed from the at least one three-dimensional body of cellulose fibres in one single pressing step in the forming mould. In the single pressing operation, the forming mould is establishing the forming pressure and the forming temperature during a single operational engagement step. Thus, in the single pressing operation, the forming pressure and the forming temperature are not applied to the at least one three- dimensional body of cellulose fibres in two or more repeated pressing steps.

[0016] In one embodiment, the forming mould comprises a first mould part and a second mould part. The method further comprises the steps: transporting at least one three- dimensional body of cellulose fibres from the shaping element into a position between the first mould part and the second mould part; applying the forming pressure by pressing the three-dimensional body of cellulose fibres between the first mould part and the second mould part; applying the forming temperature onto the at least one three-dimensional body of cellulose fibres in the forming mould. The first mould part and the second mould part are in this way cooperating for efficiently forming the cellulose product from the at least one three-dimensional body of cellulose fibres by applying the forming pressure and forming temperature.

[0017] In one embodiment, the forming mould comprises a first mould part and a second mould part forming a forming cavity, and a pressure lance having a first end and a second end extending to or partly into the forming cavity. The second end is connected to and arranged in fluid communication with a flexible membrane arranged in the forming cavity. The forming mould is configured for being displaced between an open state and a closed state. The method further comprises the steps: displacing the first mould part and / or the second mould part into the open state; transporting at least one three-dimensional body of cellulose fibres from the at least one shaping element into the forming cavity between the first mould part and the second mould part; displacing the first mould part and / or the second mould part into the closed state, wherein in the closed state the forming mould is closed around the at least one three- dimensional body of cellulose fibres in the forming cavity; in the closed state inflating the flexible membrane with a pressure medium entering from the pressure lance for applying the forming pressure onto the at least one three-dimensional body of cellulose fibres by pressing the at least one three-dimensional body of cellulose fibres against the first mould part and the second mould part by means of the inflated flexible membrane; in the closed state applying the forming temperature onto the at least one three-dimensional body of cellulose fibres. In this way, the flexible membrane when inflated by the pressure medium is applying the forming pressure onto the at least one three-dimensional body of cellulose fibres. Further, the applied forming pressure together with the applied forming temperature onto the at least one three-dimensional body of cellulose fibres are efficiently forming the cellulose product in the forming mould.

[0018] In one embodiment, the method further comprises the steps: in the open state transporting a first three-dimensional body of cellulose fibres into the first mould part and a second three-dimensional body of cellulose fibres into the second mould part, wherein the first three-dimensional body of cellulose fibres and the second three- dimensional body of cellulose fibres are arranged in the forming cavity; arranging the forming mould into the closed state, wherein in the closed state the forming mould is closed around the first three-dimensional body of cellulose fibres and the second three-dimensional body of cellulose fibres in the forming cavity; in the closed state inflating the flexible membrane with a pressure medium entering from the pressure lance for applying the forming pressure onto the first three-dimensional body of cellulose fibres and the second three-dimensional body of cellulose fibres by pressing the first three-dimensional body of cellulose fibres against the first mould part and pressing the second three-dimensional body of cellulose fibres against the second mould part by means of the inflated flexible membrane; in the closed state applying the forming temperature onto the first three-dimensional body of cellulose fibres and the second three-dimensional body of cellulose fibres. The flexible membrane is when inflated by the pressure medium applying the forming pressure onto the first three- dimensional body of cellulose fibres and the second three-dimensional body of cellulose fibres in the forming cavity. The applied forming pressure together with the applied forming temperature onto the first three-dimensional body of cellulose fibres and the second three-dimensional body of cellulose fibres are efficiently forming the cellulose product in the forming mould.

[0019] In one embodiment, the second end of the pressure lance is movably arranged relative to the first mould part and / or the second mould part. The method further comprises the steps: displacing the second end of the pressure lance relative to the first mould part and / or the second mould part into a first position in the open state of the forming mould, and displacing the second end of the pressure lance relative to the first mould part and / or the second mould part into a second position in the closed state of the forming mould. This configuration of the pressure lance is suitable when one of the first mould part and second mould part is arranged as a stationary mould part, where the other mould part is movably arranged.

[0020] In one embodiment, the product forming unit comprises a fluid control device. The pressure lance is at the first end arranged in fluid communication with the fluid control device. The method further comprises the step: inflating the flexible membrane with the pressure medium via the pressure lance by means of the fluid control device. The fluid control device is inflating the flexible membrane with the pressure medium via the pressure lance upon forming in the forming mould. The fluid control device may further be arranged for deflating the flexible membrane via the pressure lance after the forming operation in the 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.

[0021] The disclosure further concerns a product forming unit for dry-forming a cellulose product from cellulose fibres. The product forming unit comprises at least one shaping element having a shape that corresponds to the forming mould and thus to the cellulose product formed in the forming mould, a forming mould and a fibre transporting unit. The fibre transporting unit is configured for feeding loose and separated cellulose fibres into a flow of air for transporting the cellulose fibres to the at least one shaping element by means of the flow of air as carrying medium for the cellulose fibres, and configured for arranging the loose and separated cellulose fibres onto a three-dimensional surface of the at least one shaping element by means of the flow of air for air-forming at least one three-dimensional body of cellulose fibres, where the at least one three-dimensional body is provided with a shape corresponding to the shape of the cellulose product formed in the forming mould. The thickness of the at least one three-dimensional body may be uniform. The forming mould is configured for dry-forming the cellulose product into a three-dimensional compressed fibre structure by pressing and heating at least one three-dimensional body of cellulose fibres in a forming mould with a forming pressure in the range of 1-600 MPa, preferably in the range of 1-100 MPa, more preferably in the range of 4-20 MPa, and with a forming temperature in the range of 60-300 °C, preferably in the range of 100- 200 °C, more preferably in the range of 120-170 °C.

[0022] Advantages with these features are that with the product forming unit the forming of the cellulose products can be more efficient, where the cellulose products can be produced at high speeds with high quality by shaping the at least one three- dimensional body of cellulose fibres having a shape that corresponds to the forming mould before dry-forming the cellulose product into a three-dimensional compressed fibre structure in the forming mould. The handling of the fibres is simplified with the three-dimensional body of cellulose fibres, and the product forming unit is enabling the dry-forming of cellulose products with high finish at high production rates. In this way, a more efficient product forming unit for producing high-quality cellulose products is achieved, which especially is suitable for forming deep drawn products. By forming the three-dimensional body of cellulose fibres with a shape that corresponds to the forming mould, and with a substantially uniform thickness, the forming pressure can be held at a low level.

[0023] In one embodiment, the three-dimensional surface is an outer surface of the shaping element. The shaping element further comprises an inner surface opposite the outer surface. The shaping element comprises a plurality of suction openings connecting the outer surface and the inner surface. The three-dimensional surface of the shaping element is configured for receiving loose and separated cellulose fibres by means of the flow of air for air-forming the three-dimensional body of cellulose fibres upon application of a negative pressure via the suction openings for distributing the cellulose fibres onto the three-dimensional surface. The suction openings are enabling efficient deposition of the cellulose fibres onto the three-dimensional surface, and the negative pressure applied is securing a desired distribution of the cellulose fibres. The suction openings may have any suitable shape, size and configuration. The shape and / or size of the suction openings may vary between different parts of the shaping element, as well as the number of suction openings arranged in the shaping element.

[0024] In one embodiment, the shaping element is arranged as a three-dimensional net structure or as a solid perforated structure. These constructions are providing an efficient distribution of cellulose fibres onto the three-dimensional surface, while allowing the flow air to pass through the shaping element.

[0025] In one embodiment, the forming mould comprises a first mould part and a second mould part. The product forming unit further comprises a feeding unit configured for feeding at least one three-dimensional body of cellulose fibres from the shaping element into a position between the first mould part and the second mould part. The forming mould is configured for applying the forming pressure by pressing the three- dimensional body of cellulose fibres between the first mould part and the second mould part, and applying the forming temperature onto the at least one three- dimensional body of cellulose fibres. The first mould part and the second mould part are cooperating for efficiently forming the cellulose product from the at least one three- dimensional body of cellulose fibres by applying the forming pressure and forming temperature.

[0026] In one embodiment, the forming mould comprises a first mould part and a second mould part forming a forming cavity, and a pressure lance comprising a first end and a second end. The second end of the pressure lance is extending to or partly into the forming cavity. The second end is connected to and arranged in fluid communication with a flexible membrane arranged in the forming cavity. The first mould part and / or the second mould part are movably arranged at least in a lateral direction of the forming mould. The product forming unit further comprises a feeding unit configured for feeding at least one three-dimensional body of cellulose fibres from the at least one shaping element into the forming cavity between the first mould part and the second mould part in an open state of the forming mould. In a closed state of the forming mould, the flexible membrane is configured for being inflated with a pressure medium entering from the pressure lance for applying the forming pressure onto the at least one three-dimensional body of cellulose fibres by pressing the at least one three-dimensional body of cellulose fibres against the first mould part and the second mould part by means of the inflated flexible membrane. The forming mould is in the closed state configured for applying the forming temperature onto the at least one three-dimensional body of cellulose fibres. In this way, the flexible membrane when inflated by the pressure medium is applying the forming pressure onto the at least one three-dimensional body of cellulose fibres. Further, the applied forming pressure together with the applied forming temperature onto the at least one three-dimensional body of cellulose fibres are efficiently forming the cellulose product in the forming mould.

[0027] In one embodiment, the forming mould is in the open state configured for receiving a first three-dimensional body of cellulose fibres into the first mould part and a second three-dimensional body of cellulose fibres into the second mould part.

[0028] In one embodiment, the second end of the pressure lance is movably arranged relative to the first mould part and / or the second mould part. The second end of the pressure lance is configured for being arranged in a first position relative to the first mould part and / or the second mould part in the open state of the forming mould, and configured for being arranged in a second position relative to the first mould part and / or the second mould part in the closed state of the forming mould. This configuration of the pressure lance is suitable when one of the first mould part and second mould part is arranged as a stationary mould part, where the other mould part is movably arranged.

[0029] In one embodiment, the product forming unit comprises a fluid control device. The pressure lance is at the first end arranged in fluid communication with the fluid control device. The flexible membrane is configured for being inflated with the pressure medium via the pressure lance by means of the fluid control device. The fluid control device is thus used for inflating the flexible membrane with the pressure medium via the pressure lance upon forming in the forming mould. The fluid control device may further be arranged for deflating the flexible membrane via the pressure lance after the forming operation in the 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.

[0030] It should be noted that for all the above embodiments and examples, the three- dimensional surfaces of the one or more shaping elements could be either generally positive or generally negative in shape. In this context, positive means that the three- dimensional surface is intended to create a generally concave surface of the cellulose product. Here, negative means that the three-dimensional surface is intended to create a generally convex surface of the cellulose product. However, the three- dimensional surface can vary within its generally positive or negative shape such that portions of the surface can be locally positive and locally negative thereby creating an at least in part undulating shape of the cellulose product.

[0031] The disclosure further concerns a dry-formed three-dimensional cellulose product comprising compressed loose and separated cellulose fibres, wherein the cellulose product comprises at least two air-formed three-dimensional bodies of cellulose fibres being attached to each other.

[0032] In one embodiment, the dry-formed cellulose product has a bottle-shaped configuration. The cellulose product 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. The cellulose product is formed from at least a first three-dimensional body of cellulose fibres and a second three-dimensional body of cellulose fibres, and the cellulose product comprises compressed seam sections arranged between the at least first three- dimensional body of cellulose fibres and second three-dimensional body of cellulose fibres. Each seam section is extending along the cellulose product through the neck portion, the mid-portion, and the closed bottom portion. The seam sections are resulting from overlapping sections between the at least first three-dimensional body of cellulose fibres and second three-dimensional body of cellulose fibres when formed into the cellulose product in the forming mould. The overlapping configuration is securing that the cellulose product is formed without any gaps or open passages between the bodies of cellulose fibres. The seam sections are further providing rigid structural parts of the cellulose product.

[0033] In one embodiment, the seam sections are extending in the longitudinal direction of the cellulose product, or extending essentially in the longitudinal direction of the cellulose product. The extensions of the seam sections are mainly determined by the overlapping sections between the at least first three-dimensional body of cellulose fibres and second three-dimensional body of cellulose fibres, and the extensions of the seam sections along the cellulose bottle is providing a more rigid structural part along the length of the cellulose bottle.

[0034] In one embodiment, the seam sections of the neck portion have a higher basis weight and thus a higher density compared to at least adjacent parts of the neck portion outside the seam sections. The seam sections of the mid-portion have a higher basis weight and thus a higher density compared to at least adjacent parts of the mid-portion outside the seam sections. The seam sections of the closed bottom portion have a higher basis weight and thus a higher density compared to at least adjacent parts of the closed bottom portion outside the seam sections. The higher basis weight and thus density in the seam sections is resulting from the accumulation of material in the overlapping sections between the at least first three-dimensional body of cellulose fibres and second three-dimensional body of cellulose fibres, and the higher basis weight is used for providing the more rigid structural part of the cellulose bottle formed by the seam section.

[0035] BRIEF DESCRIPTION OF DRAWINGS The disclosure will be described in detail in the following, with reference to the attached drawings, in which

[0036] Fig. 1a-b show schematically, in side views, an embodiment of a product forming unit comprising a fibre transporting unit, a shaping element and a forming mould, according to the disclosure,

[0037] Fig. 2 shows schematically, in a perspective view from above, the fibre transporting unit and the shaping element, according to the disclosure,

[0038] Fig. 3a-c show schematically, in side views, forming of a three-dimensional body of cellulose fibres onto the shaping element of the product forming unit, according to the disclosure,

[0039] Fig. 4 shows schematically, in a perspective view from above, an alternative embodiment of a shaping element, according to the disclosure,

[0040] Fig. 5 shows schematically, in a perspective view from above, an alternative embodiment of a fibre transporting unit with a plurality of shaping elements, according to the disclosure,

[0041] Fig. 6a-d show schematically, in side views, an embodiment of a forming mould, according to the disclosure,

[0042] Fig. 7 shows schematically, in a side view, an embodiment of a product forming unit comprising a fibre transporting unit, a shaping element and a forming mould, according to the disclosure,

[0043] Fig. 8a-f show schematically, in side views, forming of a three-dimensional body of cellulose fibres onto the shaping element of the product forming unit, according to the disclosure,

[0044] Fig. 9a-d show schematically, in side views, forming of a cellulose product configured as a bottle, according to the disclosure,

[0045] Fig. 10 shows schematically, in a side view, details of the forming mould for forming the cellulose product configured as a bottle, according to the disclosure, Fig. 11 a-b show schematically, in perspective views, a cellulose product configured as a bottle, according to the disclosure, and

[0046] DESCRIPTION OF EXAMPLE EMBODIMENTS

[0047] 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.

[0048] In the figures, different embodiments of a product forming unit II are schematically illustrated, in which cellulose products 1 are dry-formed from cellulose fibres CF. The product forming unit II comprises at least one shaping element 2, a forming mould M and a fibre transporting unit T. The fibre transporting unit T is used for feeding loose and separated cellulose fibres CF into a flow of air A, and fortransporting the cellulose fibres CF to the at least one shaping element 2 by means of the flow of air A as carrying medium for the cellulose fibres CF.

[0049] With the expression cellulose product 1 is meant a product that is dry-formed in the forming mould M from the cellulose fibres CF. The dry-formed cellulose product 1 may be a final product ready for use in a specific application. Alternatively, the dry-formed cellulose product 1 may be a pre-formed part of a final product and thus constitute a part of an assembled final product. One or more pre-formed parts may for example be attached to each other with glue or other fastening means into a final product. In this way, the cellulose product is configured as a three-dimensional cellulose product comprising compressed loose and separated cellulose fibres, where the cellulose product comprises at least two air-formed three-dimensional bodies of cellulose fibres attached to each other.

[0050] With the expression loose and separated cellulose fibres CF is meant cellulose fibres that are separated from each other and loosely arranged relative to each other, or cellulose fibres or cellulose fibre bundles that are separated from each other and loosely arranged relative to each other. The cellulose fibres CF 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 fibre containing structures. The pulp material is preferably pure cellulose fibres, e.g. from chemically treated pulp, where most of the lignin and the hemicellulose is removed. The cellulose fibres may also be extracted from agricultural waste materials, for example wheat straws, fruit and vegetable peels, bagasse, or from other suitable sources. When for example using pulp as raw material for the cellulose fibres CF, the pulp structure commonly needs to be separated in a separating unit, such as a suitable mill unit, before feeding the loose and separated cellulose fibres CF into the flow of air A. In the separating unit, the pulp structure is separated into individual cellulose fibres, or into individual cellulose fibres and cellulose fibre bundles, and the better milling process the more individual cellulose fibres are formed. In other embodiments, only individual cellulose fibres may be used as raw material. The loose and separated cellulose fibres CF may be provided by a mill unit arranged in connection to the product forming unit II, or alternatively preprepared loose and separated cellulose fibres CF are provided to the product forming unit II.

[0051] The fibre transporting unit T is further used for arranging the loose and separated cellulose fibres CF onto a three-dimensional surface SSD of the at least one shaping element 2 by means of the flow of air A for air-forming at least one three-dimensional body B of cellulose fibres CF, which may have a substantially uniform thickness. The shape of the shaping element 2 corresponds to the shape of the forming mould M, and thus of the cellulose product 1 formed in the forming mould M. In this way, the at least one three-dimensional body B of cellulose fibres CF is air-formed in a dry and controlled fibre forming process in which the cellulose fibres CF are air-formed onto the three-dimensional surface SSD of the at least one shaping element 2 by means of the flow of air A as carrying medium for the cellulose fibres CF. It should be understood that even if the at least one three-dimensional body B of cellulose fibres CF is slightly compacted before the forming of the cellulose products 1 , such as compacting the at least one three-dimensional body B for feeding or transportation purposes, the at least one three-dimensional body B still comprises loose and separated cellulose fibres CF. A three-dimensional surface SSD of the at least one shaping element 2 is defined as a non-planar surface having a three-dimensional shape for an efficient forming of the three-dimensional body B of cellulose fibres CF. The three-dimensional surface SSD of the at least one shaping element 2 has a surface configuration adapted to the configuration of the forming mould for an efficient positioning of the three-dimensional body B of cellulose fibres CF in the forming mould M without larger deformations. The three-dimensional surface SSD of the at least one shaping element 2 may have any suitable three-dimensional configuration, and the three-dimensional surface SSD may for example be arranged with elevated, undulating, rounded and / or step-like surface sections. Suitably, the three-dimensional surface SSD of the at least one shaping element 2 has a shape corresponding to or similar to a final shape of the cellulose product 1 formed in the forming mould M. In this way, the shape of the three- dimensional body B of cellulose fibres CF has a shape corresponding to or similar to the shape of the forming mould M and thus to a final shape of the cellulose product 1 formed in the forming mould M. The thickness of the at least one three-dimensional body B may in one example be substantially equal over the complete body of the at least one three-dimensional body B. This will ensure that the wall thickness of the cellulose product will be substantially equal and will have a substantially equal density over the complete cellulose product.

[0052] With an air-formed three-dimensional body B of cellulose fibres CF is meant an essentially air-formed fibrous structure produced from cellulose fibres CF, where cellulose fibres CF are carried and formed to the three-dimensional body B of cellulose fibres CF 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 products, but air is still used as carrying medium in the forming process. The small amount of water has the advantage of enabling forming of hydrogen bonds between the fibres in the forming mould when subjected to pressure and temperature. The hydrogen bonds are an important factor for rigidity of the cellulose product.

[0053] The three-dimensional body B of cellulose fibres CF 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 products 1. The cellulose fibres CF used in the three-dimensional body B of cellulose fibres CF are during the forming process of the cellulose products 1 strongly bonded to each other. The cellulose fibres CF may be mixed with other substances or compounds to a certain amount. With cellulose fibres is meant any type of cellulose fibres, such as natural cellulose fibres or manufactured cellulose fibres. The three-dimensional body B of cellulose fibres CF may specifically comprise at least 95% cellulose fibres, or more specifically at least 99% cellulose fibres. However, the three-dimensional body B of cellulose fibres CF may have other suitable configurations and cellulose fibre amounts.

[0054] The forming mould M is used for dry-forming the cellulose products 1 into a three- dimensional compressed fibre structure CFcs by pressing and heating at least one three-dimensional body B of cellulose fibres CF in the forming mould M with a forming pressure PF in the range of 1-600 MPa, preferably with a forming pressure PF in the range of 1-100 MPa, more preferably in the range of 4-20 MPa, and a forming temperature TF in the range of 60-300 °C, preferably in the range of 100-200 °C, more preferably in the range of 120-170 °C. The forming pressure PF may selectively be higher in specific parts or areas of the forming mould M. This higher forming pressure PF may be used for forming sections of the cellulose product 1 having a higher stiffness.

[0055] It should be understood that the three-dimensional bodies B of cellulose fibres CF may have different degrees of compacting in different parts.

[0056] Figures 1a-b schematically show an embodiment of a product forming unit II in which cellulose products 1 are dry-formed from cellulose fibres CF. The product forming unit II comprises a shaping element 2, a forming mould M and a fibre transporting unit T. The fibre transporting unit T is used for feeding loose and separated cellulose fibres CF into a flow of air A, and for transporting the cellulose fibres CF to the shaping element 2 by means of the flow of air A as carrying medium for the cellulose fibres CF.

[0057] The shaping element 2 is illustrated in figures 2 and 3a-c, and the shaping element 2 comprises a three-dimensional surface SSD. A three-dimensional body B of cellulose fibres CF is air-formed onto the three-dimensional surface SSD from the cellulose fibres CF transported by the flow of air A to the shaping element 2, as will be further described below.

[0058] In the embodiment shown in figures 1a-b, 2, and 3a-c, the fibre transporting unit T comprises a flow channel 8 in which a flow of air A is introduced, for example by a suitable fan unit or other air flow establishing device of the fibre transporting unit T. The shaping element 2 is arranged in connection to the flow channel 8 to enable the distribution of cellulose fibres CF to the shaping element 2. The flow channel 8 suitably comprises a hood H or similar arrangement that at least partly is encompassing the shaping element 2, for an efficient distribution of cellulose fibres CF onto the shaping element 2. Loose and separated cellulose fibres CF are introduced into the flow of air A for forming a mix of air and cellulose fibres CF that are transported by means of the flow of air A in the flow channel 8.

[0059] In other non-illustrated embodiments, two or more flow channels 8 may be arranged in connection to the shaping elements 2, for feeding different types of cellulose fibres CF to the shaping elements 2. In this way, air-forming of the three-dimensional bodies B of cellulose fibres CF with layers of different cellulose fibres CF is enabled.

[0060] In some embodiments, a non-illustrated mill unit may be arranged in connection to the flow channel 8. The mill unit may be used for both separating cellulose raw material into loose and separated cellulose fibres CF and establishing the flow of air A in the flow channel 8, and in this way a mix of cellulose fibres CF into the flow of air A may be established directly by the mill unit.

[0061] As shown in figures 3a-b, the fibre transporting unit T is feeding the loose and separated cellulose fibres CF in the flow channel 8 to the three-dimensional surface S3D of the shaping element 2 by means of the flow of air A. The shape of the shaping element 2 corresponds to the shape of the forming mould M. By depositing the loose and separated cellulose fibres CF onto the three-dimensional surface SSD, the three- dimensional body B of cellulose fibres CF is built up on the three-dimensional surface S3D. In this way, the three-dimensional body B of cellulose fibres CF is air-formed in a dry and controlled fibre forming process in which the cellulose fibres CF are airformed onto the three-dimensional surface SSD of the shaping element 2 by means of the flow of air A as carrying medium for the cellulose fibres CF. In this way, the thickness of the three-dimensional body B may be substantially uniform and equal over the complete body. When a suitable amount of cellulose fibres CF are formed onto the three-dimensional surface SSD, as schematically shown in figure 3c, the three-dimensional body B of cellulose fibres CF is air-formed and ready for being removed from the shaping element 2 for further handling in the product forming unit U.

[0062] As shown in figures 1a-b, 2, and 3a-c, the three-dimensional surface SSD is an outer surface So of the shaping element 2. In this embodiment, the shaping element 2 further comprises an inner surface Si opposite the outer surface So, and a plurality of suction openings 7 connecting the outer surface So and the inner surface Si. The three-dimensional surface SSD of the shaping element 2 is configured for receiving the loose and separated cellulose fibres CF by means of the flow of air A for air-forming the three-dimensional body B of cellulose fibres CF upon application of a negative pressure PN via the suction openings 7 for distributing the cellulose fibres CF onto the three-dimensional surface SSD, as schematically illustrated in figures 2 and 3a-c. The shaping element 2 may suitably be arranged as a three-dimensional net structure or as a solid perforated structure. The suction openings 7 may have any suitable shape, size and configuration. The shape and / or size of the suction openings 7 may vary between different parts of the shaping element 2, as well as the number of suction openings 7 arranged in the shaping element 2.

[0063] In other non-illustrated embodiments, the shaping element 2 is only partly arranged with suction openings 7 for steering and controlling the flow of cellulose fibres CF. Depending on the geometry of the shaping element, the suction openings may be arranged such that the thickness of the resulting three-dimensional body B is either substantially uniform and equal over the complete body or is provided with a varying thickness.

[0064] In further non-illustrated embodiments, the shaping element 2 may be arranged without the suction openings, and the cellulose fibres CF are deposited onto the three- dimensional surface SSD of the shaping element 2 without the need for applying a negative pressure through the shaping element. In this way, the cellulose fibres CF are instead shot or sprayed onto the three-dimensional surface SSD by a flow of air A as carrying medium for the cellulose fibres CF. After air-forming of the three-dimensional body B on the three-dimensional surface S3D of the shaping element 2, the three-dimensional body B is transported from the shaping element 2 to the forming mould M by a feeding unit F, as shown in figures 1a-b. In the illustrated embodiment, the feeding unit F is arranged as a feeding belt. However, the feeding unit F may have any other suitable design and configuration, such as for example a robot arm, or other similar arrangement.

[0065] The forming mould M comprises a first mould part 3a and a second mould part 3b that are cooperating for forming the cellulose product 1 from the three-dimensional body B of cellulose fibres CF. The first mould part 3a and the second mould part 3b are movably arranged relative to each other, and the first mould part 3a and the second mould part 3b are configured for moving relative to each other in a pressing direction DP.

[0066] In the embodiment illustrated in figures 1a-b, the second mould part 3b is stationary and the first mould part 3a is movably arranged in relation to the second mould part 3b in the pressing direction DP, during a pressing operation OP. AS indicated with the double arrow in figures 1a-b, the first mould part 3a is configured to move both towards the second mould part 3b and away from the second mould part 3b in linear movements along an axis extending in the pressing direction Dp.

[0067] It should be understood that for all embodiments according to the disclosure, the expression moving in the pressing direction DP includes a movement in the pressing direction DP, and the movement may take place in opposite directions. The expression may further include both linear and non-linear movements of a mould part, where the result of the movement during forming is a repositioning of the mould part in the pressing direction Dp.

[0068] With the expression pressing operation OP is meant the operation of the mould parts for forming a cellulose product 1 from the three-dimensional body B of cellulose fibres CF. In the embodiment shown in figures 1a-b, the pressing operation OP starts when the first mould part 3a is moved from a stationary position. In this position, the first mould part 3a and the second mould part 3b are arranged at a distance from each other and the three-dimensional body B of cellulose fibres CF can be fed into the forming mould M in a forming position between the first mould part 3a and the second mould part 3b, as illustrated in figure 1a. The feeding unit F is configured for feeding the three-dimensional body B of cellulose fibres CF from the shaping element 2 into a position between the first mould part 3a and the second mould part 3b. Thereafter, the first mould part 3a is moved towards the second mould part 3b for applying the forming pressure PF onto the three-dimensional body B of cellulose fibres CF, as shown in figure 1b. In this way, the forming mould M is applying the forming pressure PF by pressing the three-dimensional body B of cellulose fibres CF between the first mould part 3a and the second mould part 3b. The forming mould M is further applying the forming temperature TF onto the three-dimensional body B of cellulose fibres CF.

[0069] When the cellulose product is formed in the forming mould M, the first mould part 3a is moved away from the second mould part 3b back to the stationary position. When the first mould part 3a has reached the stationary position again, the pressing operation OP is completed. The pressing operation OP is thus defined as a pressing cycle during which the three-dimensional body B of cellulose fibres CF is exerted to the forming pressure PF, and the duration of the pressing operation OP is suitably calculated from the start of the movement of the first mould part 3a from the stationary position until the first mould part 3a has reached the stationary position again.

[0070] The forming mould M is in the pressing operation OP dry-forming the cellulose product 1 into a three-dimensional compressed fibre structure CFcs by pressing and heating the three-dimensional body B of cellulose fibres CF in the forming mould M with a forming pressure PF in the range of 1-600 MPa, preferably with a forming pressure PF in the range of 1-100 MPa, more preferably in the range of 4-20 MPa, and a forming temperature TF in the range of 60-300 °C, preferably in the range of 100-200 °C, more preferably in the range of 120-170 °C.

[0071] The forming pressure PF may selectively be higher in specific parts or areas of the forming mould M. This higher forming pressure Pp may be used for forming sections of the cellulose product 1 having a higher stiffness.

[0072] The forming pressure PF may selectively be higher in specific parts or areas of the forming mould M, and in certain cases, the forming pressure PF applied onto the cellulose fibres CF in specific parts or areas of the forming mould M may be in the range of 1-600 MPa, preferably 4-200 MPa. This higher forming pressure Pp may be used for forming sections of the cellulose product 1 having a higher stiffness. The at least one three-dimensional body B of cellulose fibres CF may be compacted before dry-forming the cellulose product 1 in the forming mould M. By compacting the three-dimensional body B of cellulose fibres CF before dry-forming the cellulose product 1 in the forming mould M, the three-dimensional body B of cellulose fibres CF is easier to transport from the shaping element 2 to the forming mould M. The compacting operation is compressing the fibre structure of the three-dimensional body B of cellulose fibres CF into a more dense structure, without influencing the general three-dimensional shape. If two or more three-dimensional bodies B of cellulose fibres CF are arranged in connection to each other in a slightly overlapping relationship in the forming mould M, less compacted overlapping sections of the three-dimensional bodies B of cellulose fibres CF may be integrated with and attached to each other in the pressing operation OP.

[0073] The forming mould M may further comprise a heating unit. The heating unit is configured for applying the forming temperature Tp onto the three-dimensional body B of cellulose fibres CF during the forming operation in the forming mould M. The heating unit may have any suitable configuration. The heating unit may be integrated in or cast into the first mould part 3a and / or second mould part 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.

[0074] The forming pressure Pp may be applied to the three-dimensional body B of cellulose fibres CF in only one pressing step during the pressing operation OP. Suitably, the cellulose product 1 is formed into the three-dimensional compressed fibre structure CFcs in a single pressing operation by pressing and heating the three-dimensional body B of cellulose fibres CF in the forming mould M with the forming pressure Pp and the forming temperature Tp. In this way, the forming pressure Pp and the forming temperature Tp are applied onto the three-dimensional body B of cellulose fibres CF during a single pressing operation upon forming of the cellulose product 1 in the forming mould M. With a single pressing operation is meant that the cellulose product 1 is formed from the three-dimensional body B of cellulose fibres CF in one single pressing step in the forming mould M. In the single pressing operation, the first mould part 3a and the second mould part 3b are interacting with each other for establishing the forming pressure Pp and the forming temperature Tp during a single operational engagement step. Thus, in the single pressing operation, the forming pressure Pp and the forming temperature TF are not applied to the three-dimensional body B of cellulose fibres CF in two or more repeated pressing steps.

[0075] Alternatively, the forming pressure PF may be applied in two or more repeated pressing steps during the pressing operation OP, and in this way, the mould parts are repeatedly exerting the forming pressure PF onto the three-dimensional body B of cellulose fibres CF.

[0076] It should be understood that the forming mould M may have other configurations. In alternative non-illustrated embodiments, the first mould part 3a may be stationary and the second mould part 3b movably arranged in relation to the first mould part 3a during the pressing operation OP, or both the first mould part 3a and the second mould part 3b are movably arranged towards and away from each other.

[0077] The shaping element 2 may have any suitable shape, such as shapes with male and / or female configurations. In figure 2, a shaping element 2 with a male configuration is schematically illustrated, and in figure 4, an alternative embodiment of a shaping element 2 with a female configuration is schematically illustrated. The shape of the shaping element 2 corresponds to the shape of the forming mould M.

[0078] The shaping element 2 shown in figure 4 comprises a three-dimensional surface SSD arranged as an outer surface So. The shaping element 2 further comprises an inner surface Si opposite the outer surface So, and a plurality of suction openings 7 connecting the outer surface So and the inner surface Si. The three-dimensional surface SSD of the shaping element 2 is configured for receiving the loose and separated cellulose fibres CF by means of the flow of air A for forming the three- dimensional body B of cellulose fibres CF upon application of a negative pressure PN via the suction openings 7 for distributing the cellulose fibres CF onto the three- dimensional surface SSD, as schematically illustrated in figure 4. The shaping element 2 may suitably be arranged as a three-dimensional net structure or as a solid perforated structure. The suction openings 7 may have any suitable shape, size and configuration. The shape and / or size of the suction openings 7 may vary between different parts of the shaping element 2, as well as the number of suction openings 7 arranged in the shaping element 2. In other non-illustrated embodiments, the shaping element 2 is only partly arranged with suction openings 7 for steering and controlling the flow of cellulose fibres CF.

[0079] As described above, the shaping element 2 may be arranged without the suction openings, and the cellulose fibres CF are deposited onto the three-dimensional surface SSD of the shaping element 2 without the need for applying a negative pressure through the shaping element. In this way, the cellulose fibres CF are instead shot or sprayed onto the three-dimensional surface SSD by a flow of air A as carrying medium for the cellulose fibres CF.

[0080] A plurality of shaping elements 2 may be arranged in connection to each other for simultaneous forming of a plurality of three-dimensional bodies B of cellulose fibres CF, as shown in figure 5. In this way, the fibre transporting unit T is feeding loose and separated cellulose fibres CF in a plurality of flow channels 8 to the three-dimensional surfaces SSD of the shaping elements 2 by means of a flow of air A. By arranging the loose and separated cellulose fibres CF onto the three-dimensional surfaces SSD, the three-dimensional bodies B of cellulose fibres CF is built up on each of the three- dimensional surfaces SSD in the same way as described above. In this way, the three- dimensional bodies B of cellulose fibres CF is air-formed in a dry and controlled fibre forming process in which the cellulose fibres CF are air-formed onto the three- dimensional surfaces SSD of the shaping elements 2 by means of the flow of air A as carrying medium for the cellulose fibres CF. After forming, the three-dimensional bodies B of cellulose fibres CF are transported to the forming mould M.

[0081] The forming mould M may have a single-cavity configuration with one first mould part 3a and one second mould part 3b cooperating with each other for dry-forming the cellulose products 1. Alternatively, the forming mould M may have a multi-cavity configuration, where instead two or more first mould parts 3a are cooperating with two or more corresponding second mould parts 3b. In this way, two or more cellulose products can be produced in one pressing operation OP. A single-cavity configuration forming mould M thus comprises only one first mould part 3a and a cooperating second mould part 3b. A multi-cavity configuration forming mould M comprises two or more cooperating first mould parts 3a and second mould parts 3b.

[0082] In the embodiment illustrated in figures 1a-b, the forming mould M is arranged as a single-cavity configuration forming mould comprising a first mould part 3a and a second mould part 3b movably arranged relative to each other. In the following, the forming mould M will be described in connection to a single-cavity configuration forming mould, but the disclosure is equally applicable on multi-cavity configuration forming moulds.

[0083] The cellulose product 1 dry-formed as described above in connection to figures 1a-b may be a final product ready for use in a specific application. Alternatively, the dry- formed cellulose product 1 may be a pre-formed part of a final product and thus constitute a part of an assembled final product. As an example, two or more dry- formed cellulose products 1 could be assembled into a final product, where the two or more dry-formed cellulose products 1 constitute pre-formed parts of the final product. If for example the final product is a bottle, three cellulose products 1 dry- formed as two pre-formed upper halves and one pre-formed bottom section may be assembled into the bottle. The parts may for example be glued together for forming the final product.

[0084] The forming mould M may have other configurations than the ones described above. In the embodiment illustrated in figures 6a-d, the forming mould M comprises a first mould part 3a and a second mould part 3b. The first mould part 3a and the second mould part 3b are forming a forming cavity C. The forming mould M further comprises a pressure lance 5 having a first end 5a and a second end 5b, and the second end 5b is extending to or partly into the forming cavity C. The second end 5b is connected to and arranged in fluid communication with a flexible membrane 6 arranged in the forming cavity C, as understood from the figures. The first mould part 3a and / or the second mould part 3b are movably arranged relative to each other between an open state So and a closed state SCL, and the operation of such a forming mould M with a flexible membrane will be further described below in connection to figures 6a-d. The product forming unit II suitably comprises a fluid control device D, and the pressure lance 5 is at the first end 5a arranged in fluid communication with the fluid control device D. The flexible membrane 6 is configured for being inflated with a pressure medium P via the pressure lance 5 by means of the fluid control device D.

[0085] In the embodiment shown in figures 6a-d, the forming mould M is arranged to receive pre-shaped three-dimensional bodies B of cellulose fibres CF which may have a substantially uniform thickness, where the forming of the three-dimensional bodies B of cellulose fibres CF may be achieved by at least one shaping element 2, as for example described above in connection to figures 3a-c. The first mould part 3a and / or the second mould part 3b are movably arranged at least in a lateral direction DLA of the forming mould M. When the first mould part 3a and / or the second mould part 3b are displaced into the open state SOP, at least one three-dimensional body B of cellulose fibres CF can be transported from the at least one shaping element 2 into the forming cavity C between the first mould part 3a and the second mould part 3b. Any suitable number of three-dimensional bodies B of cellulose fibres CF may be arranged in the forming mould M. Suitably, a feeding unit F as described above is used for transporting the at least one three-dimensional body B of cellulose fibres CF from the at least one shaping element 2 into the forming cavity C of the forming mould M.

[0086] In figures 6a-d, a first three-dimensional body Bi of cellulose fibres CF is transported into the first mould part 3a and a second three-dimensional body B2 of cellulose fibres CF is transported into the second mould part 3b, in the open state SOP of the forming mould M. In this way, the first three-dimensional body Bi of cellulose fibres CF and the second three-dimensional body B2 of cellulose fibres CF are arranged in the forming cavity C.

[0087] Thereafter, the first mould part 3a and / or the second mould part 3b are displaced into the closed state SCL, as shown in figure 6c. In the closed state SCL, the forming mould M is closed around the three-dimensional bodies B of cellulose fibres CF in the forming cavity C.

[0088] To form the cellulose product 1 from the three-dimensional bodies B of cellulose fibres CF, the flexible membrane 6 is in the closed state SCL inflated with a pressure medium P entering from the pressure lance 5 for applying the forming pressure Pp onto the three-dimensional bodies B of cellulose fibres CF by pressing the at least one three- dimensional body B of cellulose fibres CF against the first mould part 3a and the second mould part 3b by means of the inflated flexible membrane 6, as shown in figure 6d. Further, in the closed state SCL, the forming temperature Tp is applied onto the three-dimensional bodies B of cellulose fibres CF.

[0089] In the embodiment shown in figures 6a-d, the first three-dimensional body Bi of cellulose fibres CF is pressed against the first mould part 3a and the second three- dimensional body B2 of cellulose fibres CF is pressed against the second mould part 3b by means of the inflated flexible membrane 6. The forming temperature TF is applied onto the first three-dimensional body Bi of cellulose fibres CF and the second three-dimensional body B2 of cellulose fibres CF. The forming pressure PF is in the range of 1-600 MPa, preferably 1-100 MPa, more preferably in the range of 4-20 MPa, and the forming temperature TF is in the range of 60-300 °C, preferably in the range of 100-200 °C, more preferably in the range of 120-170 °C.

[0090] The forming pressure PF may selectively be higher in specific parts or areas of the forming mould M, and in certain cases, the forming pressure PF applied onto the cellulose fibres CF in specific parts or areas of the forming mould M may be in the range of 1-600 MPa, preferably 4-200 MPa. This higher forming pressure Pp may be used for forming sections of the cellulose product 1 having a higher stiffness, such as the neck portion.

[0091] The forming mould M may further comprise a heating unit. The heating unit is configured for applying the forming temperature TF onto the first three-dimensional body Bi of cellulose fibres CF and the second three-dimensional body B2 of cellulose fibres CF during the forming operation in the forming mould M. The heating unit may have any suitable configuration. The heating unit may be integrated in or cast into the first mould part 3a and second mould part 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.

[0092] Suitably, the cellulose product 1 is formed into a three-dimensional compressed fibre structure CFcs in a single pressing operation by pressing and heating the first three- dimensional body Bi of cellulose fibres CF and the second three-dimensional body B2 of cellulose fibres CF in the forming mould M with the forming pressure PF and the forming temperature TF. During the forming process, the first three-dimensional body Bi of cellulose fibres CF and the second three-dimensional body B2 of cellulose fibres CF are thus integrated into the cellulose product 1 having the three-dimensional compressed fibre structure CFcs.

[0093] When closing the forming mould M, an amount of cellulose fibres CF from the first three-dimensional body Bi of cellulose fibres CF and the second three-dimensional body B2 of cellulose fibres CF may be positioned between the first mould part 3a and the second mould part 3b, and these cellulose fibres may form unwanted parting lines on the formed cellulose product 1. These parting lines may be cut off in the forming mould with suitable cutting means during the forming process, or alternatively removed after the forming process in a trimming operation.

[0094] The cellulose product 1 can be configured as a dry-formed three-dimensional cellulose product 1 comprising compressed loose and separated cellulose fibres CF, where the cellulose product 1 comprises at least two air-formed three-dimensional bodies B of cellulose fibres CF attached to each other.

[0095] A dry-formed cellulose product 1 having a bottle-shaped configuration may be formed from least a first three-dimensional body Bi of cellulose fibres CF and a second three- dimensional body B2 of cellulose fibres CF.

[0096] Figures 7, 8a-f, 9a-d, 10, and 11a-b schematically show an embodiment of a product forming unit II in which cellulose products 1 are dry-formed into bottles from cellulose fibres CF. The product forming unit II comprises a shaping element 2, a forming mould M and a fibre transporting unit T, as shown in figure 7. In the shown example, the shaping element is provided with a shape that corresponds to the shape of the first mould part 3a or the second mould part 3b. The fibre transporting unit T is used for feeding loose and separated cellulose fibres CF into a flow of air A, and for transporting the cellulose fibres CF to the shaping element 2 by means of the flow of air A as carrying medium for the cellulose fibres CF. In this embodiment, the cellulose product 1 is formed from a first three-dimensional body Bi of cellulose fibres CF and a second three-dimensional body B2 of cellulose fibres CF, as will be further described below, where in one example the thickness of the first three-dimensional body Bi and the second three-dimensional body B2 is substantially uniform.

[0097] The shaping element 2 is illustrated in figures 8a-f, and the shaping element 2 comprises a three-dimensional surface SSD. A three-dimensional body B of cellulose fibres CF is air-formed onto the three-dimensional surface SSD from the cellulose fibres CF transported by the flow of air A to the shaping element 2. The fibre transporting unit T comprises a flow channel 8 in which a flow of air A is introduced, for example by a suitable fan unit or other air flow establishing device of the fibre transporting unit T. The shaping element 2 is arranged in connection to the flow channel 8 to enable distribution of cellulose fibres CF to the shaping element 2. The flow channel 8 suitably comprises a hood H or similar arrangement that at least partly is encompassing the shaping element 2, for an efficient distribution of cellulose fibres CF onto the shaping element 2. Loose and separated cellulose fibres CF are introduced into the flow of air A for forming a mix of air and cellulose fibres CF that are transported by means of the flow of air A in the flow channel 8.

[0098] A non-illustrated mill unit may instead be arranged in connection to the flow channel 8. The mill unit may be used for both separating cellulose raw material into loose and separated cellulose fibres CF and establishing the flow of air A in the flow channel 8, and in this way a mix of cellulose fibres CF into the flow of air A may be established directly by the mill unit.

[0099] As shown in figures 8a-f, the fibre transporting unit T is feeding the loose and separated cellulose fibres CF in the flow channel 8 to the three-dimensional surface S3D of the shaping element 2 by means of the flow of air A. By arranging the loose and separated cellulose fibres CF onto the three-dimensional surface SSD, the three- dimensional body B of cellulose fibres CF is built up on the three-dimensional surface S3D, as sequentially illustrated in figures 8b-f. In this way, the three-dimensional body B of cellulose fibres CF is air-formed in a dry and controlled fibre forming process in which the cellulose fibres CF are air-formed onto the three-dimensional surface SSD of the shaping element 2 by means of the flow of air A as carrying medium for the cellulose fibres CF. When a suitable amount of cellulose fibres CF has been introduced in the flow channel 8, the feeding of cellulose fibres may be stopped, as indicated in figure 8e, and the formation of the three-dimensional body B of cellulose fibres CF may be finalised by the flow of air, as shown in figure 8f. When air-formed on the shaping element 2, the three-dimensional body B of cellulose fibres CF is ready for being removed from the shaping element 2 for further handling in the product forming unit II, as schematically shown in figure 7.

[0100] As shown in figures 8a-f, the three-dimensional surface SSD is an outer surface So of the shaping element 2. The shaping element 2 further comprises an inner surface Si opposite the outer surface So, and a plurality of suction openings 7 connecting the outer surface So and the inner surface Si. The three-dimensional surface SSD of the shaping element 2 is configured for receiving the loose and separated cellulose fibres CF by means of the flow of air A for air-forming the three-dimensional body B of cellulose fibres CF upon application of a negative pressure PN via the suction openings 7 for distributing the cellulose fibres CF onto the three-dimensional surface SSD. The shaping element 2 may suitably be arranged as a three-dimensional net structure or as a solid perforated structure. The suction openings 7 may have any suitable shape, size and configuration. The shape and / or size of the suction openings 7 may vary between different parts of the shaping element 2, as well as the number of suction openings 7 arranged in the shaping element 2. In this way, the flow of cellulose fibres CF towards the shaping element 2 can be controlled, such that the thickness of the three-dimensional body can be controlled to be either substantially uniform or be provided with a varying thickness.

[0101] In other non-illustrated embodiments, the shaping element 2 is only partly arranged with suction openings 7 for steering and controlling the flow of cellulose fibres CF.

[0102] The shaping element 2 may in further alternative embodiments be arranged without suction openings and the cellulose fibres CF are then deposited onto the three- dimensional surface of the shaping element, where the cellulose fibres CF are shot or sprayed onto the three-dimensional surface by a flow of air A as carrying medium for the cellulose fibres CF.

[0103] After air-forming of three-dimensional bodies B of cellulose fibres CF on the three- dimensional surface SSD of the shaping element 2, a first three-dimensional body Bi of cellulose fibres and a second three-dimensional body B2 of cellulose fibres CF are transported from the shaping element 2 to the forming mould M by a feeding unit F, as shown in figure 7.

[0104] A dry-formed cellulose product 1 configured as a bottle is schematically shown in figures 11a-b. The bottle 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 bottle is arranged in the position shown in figures 11a-b, 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 bottle when formed or upon forming, expressions such as above are referring to the positioning of the cellulose product 1 illustrated in figures 11a-b, where the bottle is arranged for being placed on a surface in a standing position. The mid-portion 1 b 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.

[0105] The dry-formed cellulose product 1 configured as a bottle is arranged as a rigid selfsustained cellulose-based 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 bottle via the flow opening 1ao. The closed bottom portion 1c and the mid-portion 1b are together forming a liquid holding space, and the mid-portion 1b has a hollow configuration. The wall thickness of the mid-portion 1 b and the closed bottom portion 1c is in the shown example substantially equal. The density of the mid-portion 1b and the closed bottom portion 1c is also substantially equal. The neck portion, due to the threaded section 1d, will have a varying thickness. The neck portion may have a density that is higher than the midportion 1b and the closed bottom portion 1c.

[0106] The cellulose bottle 1 further comprises compressed seam sections 1e, as shown in figures 11a-b. The seam sections 1e are in the illustrated embodiment extending along the cellulose product 1 through the neck portion 1a, the mid-portion 1b and the closed bottom portion 1c. The seam sections 1e are resulting from overlapping sections between the first three-dimensional body Bi of cellulose fibres CF and second three-dimensional body B2 of cellulose fibres CF when forming the cellulose product 1 in the forming mould M. The overlapping configuration is securing that the cellulose product 1 is formed without any gaps or open passages between the first three-dimensional body Bi of cellulose fibres CF and second three-dimensional body B2 of cellulose fibres CF. The seam sections 1e are further providing rigid structural parts of the cellulose product 1 .

[0107] The seam sections 1e are in the embodiment shown in figures 11a-b extending in the longitudinal direction DLO of the cellulose product 1 , or extending essentially in the longitudinal direction of the cellulose product 1 . The extensions of the seam sections 1e are mainly determined by the overlapping sections between the at least first three- dimensional body Bi of cellulose fibres CF and second three-dimensional body B2 of cellulose fibres CF, and the extensions of the seam sections 1e are providing rigid structural parts along the length of the cellulose bottle. The seam sections 1e of the neck portion 1a have a higher basis weight, and thus density, compared to at least adjacent parts of the neck portion 1a outside the seam sections 1. The seam sections 1e of the mid-portion 1 b have a higher basis weight, and thus density, compared to at least adjacent parts of the mid-portion 1b outside the seam sections 1e. The seam sections 1e of the closed bottom portion 1c have a higher basis weight, and thus density, compared to at least adjacent parts of the closed bottom portion 1c outside the seam sections 1e. The higher basis weight in the seam sections 1e is resulting from the accumulation of material in the overlapping sections between the at least first three-dimensional body Bi of cellulose fibres CF and second three-dimensional body B2 of cellulose fibres CF. The higher basis weight is used for providing a rigid structural part of the cellulose bottle formed by the seam section.

[0108] The neck portion 1a comprises a smooth inner surface 1a, and an outer surface 1aou arranged with the threaded section 1d. The smooth inner surface 1a, 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 bottle.

[0109] The closed bottom portion 1c is as understood from for example figure 11b configured with one or more lowest parts 1 CL. With this configuration, the one or more lowest parts 1 CL of the cellulose product 1 can be used for providing a stable bottom structure of the cellulose product 1 , where the bottom structure suitably has an inwardly curved surface configuration. The 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 the embodiment illustrated in figures 11a-b, the bottle is arranged with several lowest parts 1 CL for a high stability.

[0110] An example embodiment of a forming mould M for dry-forming cellulose products 1 configured as bottles is schematically illustrated in figures 7, 9a-d and 10. The forming mould M comprises a first mould part 3a and a second mould part 3b that are openable and closable around a forming cavity C. A flexible membrane 6 is arranged in the forming cavity C, 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 forming cavity C. The first mould part 3a and the second mould part 3b are movably arranged relative to each other and relative to the flexible membrane 6, as indicated with the double arrows in figure 9a. The first mould part 3a and / or the second mould part 3b are movably arranged at least in a lateral direction DLA of the forming mould M. The first mould part 3a is suitably displaceable in reciprocating linear movements towards and away from the second mould part 3b, and the flexible membrane 6. The second mould part 3b is suitably displaceable in reciprocating linear movements towards and away from the first mould part 3a and the flexible membrane 6. In figure 9a, the forming mould M is arranged in an open state SOP, where the first mould part 3a and the second mould part 3b have been displaced in directions away from each other and away from the flexible membrane 6, allowing the first three-dimensional body Bi of cellulose fibres CF and second three-dimensional body B2 of cellulose fibres CF to be fed around the flexible membrane 6 and received between the first mould part 3a and second mould part 3b, as shown in figure 9a.

[0111] In other non-illustrated embodiments, one of the first mould part 3a and second mould part 3b may be arranged as a stationary mould part, where the other mould part is movably arranged.

[0112] When the first three-dimensional body Bi of cellulose fibres CF and second three- dimensional body B2 of cellulose fibres CF are arranged in the forming cavity C as shown in figure 9a, the first mould part 3a and second mould part 3b are displaced towards each other for arranging the forming mould M into a closed state SCL, as shown in figure 9c.

[0113] The movements of the first mould part 3a and the second mould part 3b towards the closed state SCL are indicated with arrows in figure 9b. The first mould part 3a and second mould part 3b are in this way pushed towards each other for closing the forming mould M. Upon further movement of the first part 3a and the second mould part 3b, the mould parts are arranged in contact with each other, and the forming mould M is arranged in the closed state SCL, as shown in figure 9c. To secure the closed state SCL of the forming mould M during the forming process, the first mould part 3a and the second mould part 3b are pushed towards each other with suitable pushing forces. When closing the forming mould M, an amount of cellulose fibres CF from the first three-dimensional body Bi of cellulose fibres CF and the second three-dimensional body B2 of cellulose fibres CF may be positioned between the first mould part 3a and the second mould part 3b, and these cellulose fibres may form unwanted parting lines on the formed cellulose product 1. These parting lines may be cut off in the forming mould with suitable cutting means during the forming process, or alternatively removed after the forming process in a trimming operation.

[0114] In the closed state SCL, the first mould part 3a and the second mould part 3b together with the flexible membrane 6 are forming the cellulose product 1 by inflating the flexible membrane 6 towards the first mould part 3a and second mould part 3b. The flexible membrane 6 is inflated with a pressure medium P entering from the pressure lance 5, as indicated with the arrow in figure 9c. Thus, when the first mould part 3a and the second mould part 3b are closed around the first three-dimensional body Bi of cellulose fibres CF and second three-dimensional body B2 of cellulose fibres CF, the first three-dimensional body Bi of cellulose fibres CF and second three- dimensional body B2 of cellulose fibres CF are pressed against the first mould part 3a and the second mould part 3b by means of the inflated flexible membrane 6 for forming the cellulose bottle 1. In this way, the flexible membrane 6 is inflated with the pressure medium P entering from the pressure lance 5 for applying a forming pressure PF onto the first three-dimensional body Bi of cellulose fibres CF and the second three-dimensional body B2 of cellulose fibres CF, by pressing the first three- dimensional body Bi of cellulose fibres CF against the first mould part 3a and pressing the second three-dimensional body B2 of cellulose fibres CF against the second mould part 3b by means of the inflated flexible membrane 6. In the closed state SCL, a forming temperature TF is applied onto the first three-dimensional body Bi of cellulose fibres CF and the second three-dimensional body B2 of cellulose fibres C. During the forming process, the first three-dimensional body Bi of cellulose fibres CF and the second three-dimensional body B2 of cellulose fibres CF are integrated into a cellulose product 1 having a three-dimensional compressed fibre structure CFcs.

[0115] The bottom of the formed bottom portion 1c of the bottle has an inwardly curved surface configuration, as understood from for example figure 9d. The inwardly curved surface configuration is enabled by the shape of the first mould part 3a and second mould part 3b together with the inflation of the flexible membrane 6. The inwardly curved surface configuration is providing a stable bottom structure of the bottle. The cellulose product 1 has with this construction a high stability when placed on an object surface, such as for example a table surface or other surface.

[0116] The forming pressure PF applied onto the cellulose fibres CF by means of the flexible membrane 6 is in the range of 1-600 MPa, preferably 1-100 MPa, more preferably in the range of 4-20 MPa, and the forming temperature TF is in the range of 60-300 °C, preferably in the range of 100-200 °C, more preferably in the range of 120-170 °C.

[0117] After the forming operation, the forming mould M is returned to the open state So, as shown in figure 9d, for an easy removal of the cellulose bottle 1 and for repeating the forming operation.

[0118] The first mould part 3a and second mould part 3b of the forming mould M 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.

[0119] The forming mould M may further comprise a heating unit. The heating unit is configured for applying the forming temperature TF onto the first three-dimensional body Bi of cellulose fibres CF and the second three-dimensional body B2 of cellulose fibres CF during the forming operation in the forming mould M. The heating unit may have any suitable configuration. The heating unit may be integrated in or cast into the first mould part 3a and second mould part 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.

[0120] 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 forming mould M. 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.

[0121] The pressure medium P is used for establishing the forming pressure PF in the forming cavity C upon inflating the flexible membrane 6. The pressure medium P used in the forming operation in the forming mould M may be a liquid composition or a gas, such as for example oil, water, or air.

[0122] The product forming unit II comprises a fluid control device D, as schematically indicated in figure 9a. 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 forming mould M. 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 forming mould M. The fluid control device D 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 product forming unit II may further comprise a control unit for controlling the forming operation.

[0123] The forming pressure may selectively be higher in specific parts or areas of the forming mould M. In the embodiment shown in figures 9a-d and 10, the first mould part 3a and the second mould part 3b are each arranged with a neck forming section 3c. When the forming mould M is arranged in the closed state SCL, the neck forming sections 3c are establishing a neck forming gap G between the neck forming sections 3c and the pressure lance 5, around an outer periphery of the pressure lance 5, as indicated in figure 9c. The neck forming sections 3c are suitably arranged with threaded patterns for efficient forming of threads of the threaded section 1d on the outside surface of the neck portion 1a in the forming mould M, as understood from the figures.

[0124] When the first three-dimensional body Bi of cellulose fibres CF and the second three- dimensional body B2 of cellulose fibres CF are arranged in the forming cavity C as shown in figure 9a, the neck forming sections 3c of the first mould part 3a and second mould part 3b are displaced towards the pressure lance 5 upon arranging the forming mould M into the closed state SCL, as shown in figure 9c. When closed, the first mould part 3a and second mould part 3b are pressing the cellulose fibres CF radially against the pressure lance 5 for forming the neck portion 1a. During the pressing operation, a neck forming pressure PFN and a neck forming temperature TFN are applied onto the parts of the first three-dimensional body Bi of cellulose fibres CF and second three- dimensional body B2 of cellulose fibres CF used for forming the neck portion 1a in the forming cavity C. The neck forming pressure PFN is in this way established through interaction between the neck forming sections 3c and the pressure lance 5. The neck forming temperature TFN is suitably established by the heating unit.

[0125] The applied neck forming pressure PFN in the forming mould M is suitably in the range of 1-600 MPa, preferably 4-200 MPa, and the applied neck forming temperature TFN is suitably in the range of 60-300 °C, preferably 100-200 °C. This higher neck forming pressure Pp may be used for forming the neck portion 1a of the cellulose product 1 with a higher stiffness compared to other parts of the bottle.

[0126] The neck forming sections 3c of the first mould part 3a and second mould part 3b are suitably arranged as stiff mould sections. With stiff mould sections is meant that the mould sections 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 forming mould M in connection to the neck forming sections 3c 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 5 may be stiffer than the other parts of the pressure lance 5 to withstand the high forming pressure in the forming mould M. In one embodiment, the section of the pressure lance 5 extending through the forming mould M is reinforced with an outer structural piece of material surrounding the pressure lance 5, establishing a strong structural part around the pressure lance 5.

[0127] After the forming operation, the forming mould M is returned to the open state So, as shown in figure 9d, for an easy removal of the cellulose bottle 1 and for repeating the forming operation.

[0128] The product forming unit II may further comprise a cutting device 9 arranged in the forming mould M or in connection to the forming mould M. In the embodiment illustrated in figures 9a-d and 10, a cutting device 9 is arranged with cutting edges 9a on the first mould part 3a and the second mould part 3b respectively. The cutting device 9 is via a cutting action shaping the formed neck portion 1a of the cellulose product 1. In figure 10, the forming mould M is illustrated in the closed state SCL before the inflation of the flexible membrane 6 with the pressure medium P, and the cutting operation is suitably completed when the forming mould M is closed around the first three-dimensional body Bi of cellulose fibres CF and the second three-dimensional body B2 of cellulose fibres CF.

[0129] According to the embodiment shown in figures 9a-d and 10, the pressure lance 5 extends partly into the forming mould M. The cutting device 9 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 9a are pressed, and the neck portion 1a is in this way efficiently shaped. The pressure lance 5 may comprise a reinforced portion that can withstand the pressure from the cutting edges 9a. 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 in the forming mould M. The reinforced portion can alternatively be arranged as a separate piece of material arranged around the pressure lance 5.

[0130] The bottle forming unit II may further comprise an auxiliary cutting device 10 arranged in the forming mould M, as illustrated in figure 10. The auxiliary cutting device 10 may be arranged with cutting edges 10a on the first mould part 3a and the second mould part 3b respectively. The auxiliary cutting device 10 is cutting off residual parts of the first three-dimensional body Bi of cellulose fibres CF and the second three- dimensional body B2 of cellulose fibres CF that may extend out from the forming mould M when arranged in the closed state SCL.

[0131] The dry-formed cellulose products 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 1b are together forming a liquid holding space, and the mid-portion 1 b has a hollow configuration.

[0132] In other non-illustrated embodiments, the second end 5b of the pressure lance 5 may be movably arranged relative to the first mould part 3a and / or the second mould part 3b. In this way, the second end 5b of the pressure lance 5 is configured for being arranged in a first position relative to the first mould part 3a and / or the second mould part 3b in the open state SOP of the forming mould M, and configured for being arranged in a second position relative to the first mould part 3a and / or the second mould part 3b in the closed state SCL of the forming mould M. This configuration of the pressure lance 5 is suitable when one of the first mould part 3a and second mould part 3b is arranged as a stationary mould part, where the other mould part is movably arranged.

[0133] For the different embodiments, the at least one three-dimensional body B of cellulose fibres CF may have a moisture content in the range of 4-15 wt%, preferably in the range of 6-10 wt%, when arranged in the forming mould M.

[0134] The product forming unit II may further be arranged with a non-illustrated transporting device for transportation of formed cellulose products 1 away from the forming mould M.

[0135] In other non-illustrated embodiments, cellulose fibres CF may also be arranged between the shaping elements 2 for forming a fibre structure with three-dimensional bodies B of cellulose fibres CF connected to each other by cellulose fibres CF. This will result in a structure with interlinked three-dimensional bodies B of cellulose fibres CF for simple transport from the shaping unit S to the forming mould M.

[0136] 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

[0137] 1 : Cellulose product

[0138] 1a: Neck portion

[0139] 1ao: Flow opening

[0140] 1ar Inner surface

[0141] 1 aou: Outer surface

[0142] 1b: Mid-portion

[0143] 1c: Closed bottom portion

[0144] 1d: Threaded section

[0145] 1e: Seam section

[0146] 2: Shaping element

[0147] 3a: First mould part

[0148] 3b: Second mould part

[0149] 3c: Neck forming section

[0150] 5: Pressure lance

[0151] 5a: First end

[0152] 5b: Second end

[0153] 6: Flexible membrane

[0154] 7: Suction opening

[0155] 8: Flow channel

[0156] 9: Cutting device

[0157] 9a: Cutting edge

[0158] 10: Auxiliary cutting device

[0159] 10a: Cutting edge

[0160] A: Air

[0161] B: Three-dimensional body

[0162] C: Forming cavity

[0163] CF: Cellulose fibres

[0164] CFcs: Compressed fibre structure

[0165] D: Fluid control device

[0166] DLA: Lateral direction

[0167] DLO: Longitudinal direction

[0168] Dp: Pressing direction F: Feeding unit

[0169] G: Neck forming gap

[0170] H: Hood

[0171] M: Forming mould

[0172] OP: Pressing operation

[0173] P: Pressure medium

[0174] PF: Forming pressure

[0175] PFN: Neck forming pressure

[0176] SSD: Three-dimensional surface

[0177] Si: Inner surface

[0178] So: Outer surface

[0179] SCL: Closed state

[0180] SOP: Open state

[0181] T: Fibre transporting unit

[0182] Tp: Forming temperature

[0183] TFN: Neck forming temperature

[0184] II: Product forming unit

Claims

CLAIMS1. A method for dry-forming a cellulose product (1) from cellulose fibres (CF) in a product forming unit (II), wherein the product forming unit (II) comprises at least one shaping element (2) and a forming mould (M), wherein the at least one shaping element (2) is provided with a shape corresponding to the shape of the forming mould (M), wherein the method comprises the steps: providing loose and separated cellulose fibres (CF) and feeding the loose and separated cellulose fibres (CF) into a flow of air (A) for transporting the cellulose fibres (CF) to the at least one shaping element (2) by means of the flow of air (A) as carrying medium for the cellulose fibres (CF); arranging the loose and separated cellulose fibres (CF) onto a three- dimensional surface (SSD) of the at least one shaping element (2) by means of the flow of air (A) for air-forming at least one three-dimensional body (B) of cellulose fibres (CF), where the at least one three-dimensional body (B) is provided with a shape corresponding to the shape of the cellulose product (1) formed in the forming mould (M); feeding the at least one three-dimensional body (B) of cellulose fibres (CF) from the shaping element (2) to the forming mould (M); dry-forming the cellulose product (1) into a three-dimensional compressed fibre structure (CFcs) by pressing and heating at least one three- dimensional body (B) of cellulose fibres (CF) in the forming mould (M) with a forming pressure (PF) in the range of 1-600 MPa, preferably in the range of 1-100 MPa, more preferably in the range of 4-20 MPa, and with a forming temperature (TF) in the range of 60-300 °C, preferably in the range of 100-200 °C, more preferably in the range of 120-170 °C.

2. The method according to claim 1 , wherein the three-dimensional surface (SSD) is an outer surface (So) of the shaping element (2), wherein the shaping element (2) further comprises an inner surface (Si) opposite the outer surface (So), wherein the shaping element (2) comprises a plurality of suction openings (7) connecting the outer surface (So) and the inner surface (Si), wherein the method further comprises the steps: arranging the loose and separated cellulose fibres (CF) onto the three- dimensional surface (SSD) of the shaping element (2) by means of the flow of air(A) for air-forming the three-dimensional body (B) of cellulose fibres (CF), and applying a negative pressure (PN) via the suction openings (7) for distributing the cellulose fibres (CF) onto the three-dimensional surface (SSD).

3. The method according to claim 1 or 2, wherein the shaping element (2) is arranged as a three-dimensional net structure or as a solid perforated structure.

4. The method according to any preceding claim, wherein the at least one three-dimensional body (B) of cellulose fibres (CF) has a moisture content in the range of 4-15 wt%, preferably in the range of 6-10 wt%, when arranged in the forming mould (M).

5. The method according to any preceding claim, wherein the method further comprises the steps: forming the cellulose product (1) into the three-dimensional compressed fibre structure (CFcs) in a single pressing operation by pressing and heating at least one three-dimensional body (B) of cellulose fibres (CF) in the forming mould (M) with the forming pressure (PF) and the forming temperature (TF).

6. The method according to any of claims 1 to 5, wherein the forming mould (M) comprises a first mould part (3a) and a second mould part (3b), wherein the method further comprises the steps: transporting at least one three-dimensional body (B) of cellulose fibres (CF) from the shaping element (2) into a position between the first mould part (3a) and the second mould part (3b); applying the forming pressure (PF) by pressing the three-dimensional body (B) of cellulose fibres (CF) between the first mould part (3a) and the second mould part (3b); applying the forming temperature (TF) onto the at least one three- dimensional body (B) of cellulose fibres (CF) in the forming mould (M).

7. The method according to any of claims 1 to 5,wherein the forming mould (M) comprises a first mould part (3a) and a second mould part (3b) forming a forming cavity (C), and a pressure lance (5) having a first end (5a) and a second end (5b) extending to or partly into the forming cavity (C), wherein the second end (5b) is connected to and arranged in fluid communication with a flexible membrane (6) arranged in the forming cavity (C), wherein the forming mould (M) is configured for being displaced between an open state (SOP) and a closed state (SCL), wherein the method further comprises the steps: displacing the first mould part (3a) and / or the second mould part (3b) into the open state (SOP); transporting at least one three-dimensional body (B) of cellulose fibres (CF) from the at least one shaping element (2) into the forming cavity (C) between the first mould part (3a) and the second mould part (3b); displacing the first mould part (3a) and / or the second mould part (3b) into the closed state (SCL), wherein in the closed state (SCL) the forming mould (M) is closed around the at least one three-dimensional body (B) of cellulose fibres (CF) in the forming cavity (C); in the closed state (SCL) inflating the flexible membrane (6) with a pressure medium (P) entering from the pressure lance (5) for applying the forming pressure (Pp) onto the at least one three-dimensional body (B) of cellulose fibres (CF) by pressing the at least one three-dimensional body (B) of cellulose fibres (CF) against the first mould part (3a) and the second mould part (3b) by means of the inflated flexible membrane (6); in the closed state (SCL) applying the forming temperature (Tp) onto the at least one three-dimensional body (B) of cellulose fibres (CF).

8. The method according to claim 7, wherein the method further comprises the steps: in the open state (SOP) transporting a first three-dimensional body (Bi) of cellulose fibres (CF) into the first mould part (3a) and a second three-dimensional body (B2) of cellulose fibres (CF) into the second mould part (3b), wherein the first three-dimensional body (Bi) of cellulose fibres (CF) and the second three-dimensional body (B2) of cellulose fibres (CF) are arranged in the forming cavity (C);arranging the forming mould (M) into the closed state (SCL), wherein in the closed state (SCL) the forming mould (M) is closed around the first three- dimensional body (Bi) of cellulose fibres (CF) and the second three-dimensional body (B2) of cellulose fibres (CF) in the forming cavity (C); in the closed state (SCL) inflating the flexible membrane (6) with a pressure medium (P) entering from the pressure lance (5) for applying the forming pressure (PF) onto the first three-dimensional body (Bi) of cellulose fibres (CF) and the second three-dimensional body (B2) of cellulose fibres (CF) by pressing the first three-dimensional body (Bi) of cellulose fibres (CF) against the first mould part (3a) and pressing the second three-dimensional body (B2) of cellulose fibres (CF) against the second mould part (3b) by means of the inflated flexible membrane (6); in the closed state (SCL) applying the forming temperature (TF) onto the first three-dimensional body (Bi) of cellulose fibres (CF) and the second three- dimensional body (B2) of cellulose fibres (CF).

9. The method according claim 7 or 8, wherein the second end (5b) of the pressure lance (5) is movably arranged relative to the first mould part (3a) and / or the second mould part (3b), wherein the method further comprises the steps: displacing the second end (5b) of the pressure lance (5) relative to the first mould part (3a) and / or the second mould part (3b) into a first position in the open state (SOP) of the forming mould (M), and displacing the second end (5b) of the pressure lance (5) relative to the first mould part (3a) and / or the second mould part (3b) into a second position in the closed state (SCL) of the forming mould (M).

10. The method according to any of claims 7 to 9, wherein the product forming unit (II) comprises a fluid control device (D), wherein the pressure lance (5) at the first end (5a) is arranged in fluid communication with the fluid control device (D), wherein the method further comprises the step: inflating the flexible membrane (6) with the pressure medium (P) via the pressure lance (5) by means of the fluid control device (D).

11. A product forming unit (II) for dry-forming a cellulose product (1) from cellulose fibres (CF), wherein the product forming unit (II) comprises at least one shaping element (2), a forming mould (M) and a fibre transporting unit (T), wherein the shape of the shaping element (2) corresponds to the shape of the forming mould (M), wherein the fibre transporting unit (T) is configured for feeding loose and separated cellulose fibres (CF) into a flow of air (A) for transporting the cellulose fibres (CF) to the at least one shaping element (2) by means of the flow of air (A) as carrying medium for the cellulose fibres (CF), and configured for arranging the loose and separated cellulose fibres (CF) onto a three-dimensional surface (SSD) of the at least one shaping element (2) by means of the flow of air (A) for airforming at least one three-dimensional body (B) of cellulose fibres (CF), where the at least one three-dimensional body (B) is provided with a shape corresponding to the shape of the cellulose product (1) formed in the forming mould (M), wherein the forming mould (M) is configured for dry-forming the cellulose product (1) into a three-dimensional compressed fibre structure (CFcs) by pressing and heating at least one three-dimensional body (B) of cellulose fibres (CF) in the forming mould (M) with a forming pressure (PF) in the range of 1-600 MPa, preferably in the range of 1-100 MPa, more preferably in the range of 4-20 MPa, and with a forming temperature (TF) in the range of 60-300 °C, preferably in the range of 100-200 °C, more preferably in the range of 120-170 °C.

12. The product forming unit (II) according to claim 11 , wherein the three-dimensional surface (SSD) is an outer surface (So) of the shaping element (2), wherein the shaping element (2) further comprises an inner surface (Si) opposite the outer surface (So), wherein the shaping element (2) comprises a plurality of suction openings (7) connecting the outer surface (So) and the inner surface (Si), wherein the three-dimensional surface (SSD) of the shaping element (2) is configured for receiving loose and separated cellulose fibres (CF) by means of the flow of air (A) for air-forming the three-dimensional body (B) of cellulose fibres (CF) upon application of a negative pressure (PN) via the suction openings (7) for distributing the cellulose fibres (CF) onto the three- dimensional surface (SSD).

13. The product forming unit (II) according to claim 11 or 12, wherein the shaping element (2) is arranged as a three-dimensional net structure or as a solid perforated structure.

14. The product forming unit (II) according to any of claims 11 to 13, wherein the forming mould (M) comprises a first mould part (3a) and a second mould part (3b), wherein the product forming unit (II) further comprises a feeding unit (F) configured for feeding at least one three-dimensional body (B) of cellulose fibres (CF) from the shaping element (2) into a position between the first mould part (3a) and the second mould part (3b), wherein the forming mould (M) is configured for applying the forming pressure (PF) by pressing the three- dimensional body (B) of cellulose fibres (CF) between the first mould part (3a) and the second mould part (3b), and applying the forming temperature (TF) onto the at least one three-dimensional body (B) of cellulose fibres (CF).

15. The product forming unit (II) according to any of claims 11 to 13, wherein the forming mould (M) comprises a first mould part (3a) and a second mould part (3b) forming a forming cavity (C), and a pressure lance (5) comprising a first end (5a) and a second end (5b), wherein the second end (5b) of the pressure lance (5) is extending to or partly into the forming cavity (C), and wherein the second end (5b) is connected to and arranged in fluid communication with a flexible membrane (6) arranged in the forming cavity (C), wherein the first mould part (3a) and / or the second mould part (3b) are movably arranged at least in a lateral direction (DLA) of the forming mould (M), wherein the product forming unit (II) further comprises a feeding unit (F) configured for feeding at least one three-dimensional body (B) of cellulose fibres (CF) from the at least one shaping element (2) into the forming cavity (C) between the first mould part (3a) and the second mould part (3b) in an open state (SOP) of the forming mould (M), wherein in a closed state (SCL) of the forming mould (M) the flexible membrane (6) is configured for being inflated with a pressure medium (P) entering from the pressure lance (5) for applying the forming pressure (PF) onto the at least one three-dimensional body (B) of cellulose fibres (CF) by pressing the at least one three-dimensional body (B) of cellulose fibres (CF)against the first mould part (3a) and the second mould part (3b) by means of the inflated flexible membrane (6), wherein the forming mould (M) in the closed state (SCL) is configured for applying the forming temperature (TF) onto the at least one three-dimensional body (B) of cellulose fibres (CF).

16. The product forming unit (II) according to claim 15, wherein the forming mould (M) in the open state (SOP) is configured for receiving a first three-dimensional body (Bi) of cellulose fibres (CF) into the first mould part (3a) and a second three-dimensional body (B2) of cellulose fibres (CF) into the second mould part (3b).

17. The product forming unit (II) according to claim 15 or 16, wherein the second end (5b) of the pressure lance (5) is movably arranged relative to the first mould part (3a) and / or the second mould part (3b), wherein the second end (5b) of the pressure lance (5) is configured for being arranged in a first position relative to the first mould part (3a) and / or the second mould part (3b) in the open state (SOP) of the forming mould (M), and configured for being arranged in a second position relative to the first mould part (3a) and / or the second mould part (3b) in the closed state (SCL) of the forming mould (M).

18. The product forming unit (II) according to any of claims 15 to 17, wherein the product forming unit (II) comprises a fluid control device (D), wherein the pressure lance (5) at the first end (5a) is arranged in fluid communication with the fluid control device (D), wherein the flexible membrane (6) is configured for being inflated with the pressure medium (P) via the pressure lance (5) by means of the fluid control device (D).

19. A dry-formed three-dimensional cellulose product (1) comprising compressed loose and separated cellulose fibres (CF), wherein the cellulose product (1) comprises at least two air-formed three-dimensional bodies (B) of cellulose fibres (CF) being attached to each other.

20. The dry-formed cellulose product (1) according to claim 19, having a bottleshaped configuration, wherein the cellulose product (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 (DLO) between the closed bottom portion (1c) and the neck portion (1a), wherein the mid-portion (1 b) is arranged in fluid communication with the neck portion (1a), wherein the cellulose product (1) is formed from at least a first three- dimensional body (Bi) of cellulose fibres (CF) and a second three-dimensional body (B2) of cellulose fibres (CF), wherein the cellulose product (1) comprises compressed seam sections (1e) arranged between the at least first three- dimensional body (Bi) of cellulose fibres (CF) and second three-dimensional body (B2) of cellulose fibres (CF), wherein each seam section (1e) is extending along the cellulose product (1) through the neck portion (1a), the mid-portion (1b), and the closed bottom portion (1c).

21. The dry-formed cellulose product (1) according to claim 20, wherein the seam sections (1e) are extending in the longitudinal direction (DLO) of the cellulose product (1), or extending essentially in the longitudinal direction (DLO) of the cellulose product (1).

22. The dry-formed cellulose product (1) according to claim 20 or 21 , wherein the seam sections (1e) of the neck portion (1a) have a higher basis weight compared to at least adjacent parts of the neck portion (1a) outside the seam sections (1e), wherein the seam sections (1e) of the mid-portion (1b) have a higher basis weight compared to at least adjacent parts of the mid-portion (1 b) outside the seam sections (1 e), and wherein the seam sections (1 e) of the closed bottom portion (1c) have a higher basis weight compared to at least adjacent parts of the closed bottom portion (1c) outside the seam sections (1 e).

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