Method and apparatus for dry manufacturing rigid cellulose products

Abstract

The present invention relates to an apparatus and method for dry manufacturing rigid cellulose products (2) having essentially non-flat general shape from a discrete cellulose blank. The apparatus comprises a moulding tool having a first mould part (15) and a second mould part (16), wherein at least one of the first mould part (17) and the second mould part (18) is displaceable in the axial direction in relation to the other in order to press the cellulose blank therebetween. The first mould part (15) comprises a lower press-surface (23) and a cylinder-shaped inner guide wall surface (27), wherein the cylinder-shaped inner guide wall surface (27) defines a guide chamber (28), and the second mould part (16) comprises an upper press-surface (19) and a cylinder-shaped outer guide wall surface (29), wherein the cylinder-shaped outer guide wall surface (29) defines a guide body (30). The cross-section of the outer guide wall surface (29) corresponding to the cross-section of the inner guide wall surface (27), and a gap (Y) in the transversal direction between the inner guide wall surface (27) and the outer guide wall surface (29) is equal to or more than 0,015 mm and equal to or less than 0,5 mm.

Description

[0001] METHOD AND APPARATUS FOR DRY MANUFACTURING RIGID CELLULOSE PRODUCTS Technical field of the Invention

[0002] The present invention relates in general to the field of method and apparatus for dry manufacturing of rigid cellulose products having non-flat general shape from a cellulose blank. Such cellulose products may be used for packaging, storing, transporting and / or displaying other products such as electronics, tools, jewelry, food, dairy products, cosmetics, etc., and / or may be used as single / multiple use disposable articles, such as trays, cups, lids, plates, etc. The method and apparatus are especially defined to provide cellulose products having a distinct and well-defined edge. By cellulose products means products that mainly consists of the cellulose part of organic matter.

[0003] The present invention relates specifically to a method for dry manufacturing rigid cellulose products having essentially non-flat general shape from a discrete cellulose blank, wherein the method is performed in an apparatus comprising a cellulose blank forming unit and a product forming unit having a moulding tool and heating means for heating the discrete cellulose blank to a forming temperature T, wherein the moulding tool comprises a first mould part and a second mould part,

[0004] - the first mould part comprises a lower press-surface and a cylinder-shaped inner guide wall surface located adjacent to and extending in the axial direction from the lower press-surface of the first mould part, wherein the cylinder-shaped inner guide wall surface defines a guide chamber,

[0005] - the second mould part comprises an upper press-surface and a cylinder-shaped outer guide wall surface located adjacent to and extending in the axial direction from the upper press-surface of the second mould part, wherein the cylinder-shaped outer guide wall surface defines a guide body, the cross-section of the outer guide wall surface corresponding to the cross-section of the inner guide wall surface.

[0006] The present invention also relates specifically to an apparatus for dry manufacturing rigid cellulose products having essentially non-flat general shape from a discrete cellulose blank, wherein the apparatus comprises a cellulose blank forming unit and a product forming unit having a moulding tool and heating means for heating the discrete cellulose blank to a forming temperature T, wherein the moulding tool comprises a first mould part and a second mould part,

[0007] - the first mould part comprises a lower press-surface and a cylinder-shaped inner guide wall surface located adjacent to and extending in the axial direction from the lower press-surface of the first mould part, wherein the cylinder-shaped inner guide wall surface defines a guide chamber, and

[0008] - the second mould part comprises an upper press-surface and a cylinder-shaped outer guide wall surface located adjacent to and extending in the axial direction from the upper press-surface of the second mould part, wherein the cylinder-shaped outer guide wall surface defines a guidebody, the cross-section of the outer guide wall surface corresponding to the cross-section of the inner guide wall surface.

[0009] Thus, the present invention belongs to the general fields of air / dry-laid cellulose blanks and thermoforming rigid cellulose products.

[0010] Background of the Invention

[0011] There are many situations where it is desirable to provide two-dimensional (2D) or three-dimensional (3D) shaped objects made of sustainable materials, such as biomaterials, instead of using plastic / polymer materials. There is a general requirement to decrease the overall use of plastics, in favour of biodegradable materials.

[0012] A biodegradable material commonly used for packaging and disposable articles is wet moulded pulp based on cellulose fibres. Such wet moulded pulp has the advantage of being considered a sustainable material, since it is produced from biomaterials and can be recycled after use. Wet moulded pulp comprises more or less only water and separated cellulose fibers, and consequently, wet moulded pulp has been popular to use for primary packaging applications (packaging next to the article), for secondary packaging applications (assembly of such primary packages), as well as for manufacturing of disposable articles / products.

[0013] However, a common disadvantage with all wet -forming techniques is the need for large amounts of water during the preparations of the cellulose pulp and the need for drying during the manufacturing / moulding of the cellulose product, which is a time and energy consuming step leading to low production speed and substantial high investment cost in machines and tooling. Meaning that the wet-forming techniques are not feasible to replace fossil-based alternatives neither in small nor large scale production of rigid cellulose products. Thereto, the aesthetical and mechanical properties of a wet-moulded cellulose product are hard to control with desirable precision, due to un-uniform cellulose pulp and due to the wet moulding manufacturing technique perse.

[0014] Therefore many actors / companies, starting a few decades ago, have changed their focus and investments towards dry-forming techniques wherein rigid cellulose products are manufactured from separated cellulose fibres that are introduced into a product forming unit in the shape of a dry cellulose blank / web, wherein the cellulose blank is formed / moulded into the shape of the intended cellulose product and wherein the cellulose fibres are bonded to each other using heat and pressure, i.e. thermoforming press. The dry-forming techniques comprises different steps of generating an airlaid cellulose blank, the cellulose blank being transferred into a product forming unit and pressed.

[0015] The technical field of dry manufacturing rigid cellulose products having essentially non-flat general shape, such as trays, cups, plates, lids, or the like, i.e. wherein the forming / pressing is performed in one step using a moulding tool having a first / female mould part and a second / male mould part configured to cooperate with each other, is well known. However, when producing rigid cellulose products by means of dry manufacturing (thermo-forming) the edges are usually trimmed in order to obtain a nice aesthetic appearance and correct dimensions of the cellulose product.However, high precision of the mechanical properties of the edges / rims of the cellulose product may be hard to reach, i.e. the edges / rims may become frayed and sensitive to absorb moisture. There is also a problem of loose fibres originating from the trimmed edge / rim and / or from the scrap material that is cut off from the cellulose product. Thereto, it is an imminent risk that the rim of the trimmed cellulose product is irregular due to incorrect / varying positioning of the pressed cellulose products in the trimming unit.

[0016] SE545309 discloses a method for pressing a portion of a larger cellulose blank, wherein the portion of the cellulose blank that is subject to thermo-pressing is cut out from the larger cellulose blank by means of the moulding tool during the pressing, i.e. during the closing of the mould the portion of the cellulose blank is cut from the larger cellulose blank.

[0017] EP3882167 discloses a method for trimming the edge / rim of a thermo-formed cellulose product, wherein the cutting is performed concurrently with the closing of the mould by means of the mould parts, i.e. in the same press motion as when forming the cellulose product in the forming mould.

[0018] According to the above prior art. When the cutting edge engage the cellulose blank before the cellulose blank obtains its final shape, i.e. before it is fully pre-shaped before final pressing, or cutting is performed before the cellulose blank obtains its final shape, there is material draw after the cutting is initiated / performed and the final rim will be frayed and un-defined. Thereto, there will be a lot of dust and loose cellulose fibres originating from the scrap material and the handling of the scrap material, wherein the amount of loose fibres will contaminate the surrounding environment.

[0019] Thus, the sub-technical field of trimming / cutting-off the residual cellulose material from the rim portion of the cellulose product, is still exposed to challenges.

[0020] There is a need in the art for a reliable, cheap and unharmful dry-forming technique / process for dry manufacturing rigid cellulose products having non-flat general shape having distinct and well-defined edge.

[0021] Object of the Invention

[0022] The present invention aims at obviating the aforementioned and other disadvantages and failings of previously known methods and apparatus for dry manufacturing rigid cellulose products, and at providing an improved method and apparatus for dry manufacturing rigid cellulose products having non-flat general shape having distinct and well-defined edge.

[0023] A primary object of the present invention is to provide an improved method and apparatus for dry forming / manufacturing rigid cellulose products having non-flat general shape, wherein the environmental benefits as well as time and energy saving benefits of conventional dry-forming techniques are maintained. It is another object of the present invention to provide an improved method and apparatus for dry forming / manufacturing rigid cellulose products having non-flat general shape, wherein the final rim of the cellulose product has the desired aesthetic and mechanical properties. It is another object of the present invention to provide an improved methodand apparatus for dry forming / manufacturing rigid cellulose products having non-flat general shape, wherein the dust generation and the amount of loose cellulose fibres during pressing and trimming is significantly reduced or eliminated.

[0024] of the Invention

[0025] According to the invention at least the primary object is attained by means of the initially defined method and apparatus having the features defined in the independent claims. Preferred embodiments of the present invention are further defined in the dependent claims.

[0026] According to a first aspect of the present invention, there is provided a method for dry manufacturing rigid cellulose products having essentially non-flat general shape from a discrete cellulose blank of the initially defined type, wherein the method is characterized by the steps of: - providing a discrete cellulose blank,

[0027] - transferring the discrete cellulose blank into the moulding tool, by inserting the discrete cellulose blank into the guide chamber of the first mould part,

[0028] - closing the moulding tool by telescopically inserting the guide body of the second mould part into the guide chamber of the first mould part,

[0029] - pressing the heated cellulose blank by applying a forming pressure P in the axial direction of the moulding tool, wherein the cellulose blank is pressed in a press-cavity delimited by said lower press-surface, said upper press-surface and said inner guide wall surface,

[0030] - displacing at least one of the first mould part and the second mould part in the axial direction in relation to each other, away from each other, and

[0031] - removing the pressed cellulose product having a distinct edge from the moulding tool, wherein a gap in the transversal direction between the inner guide wall surface and the outer guide wall surface is equal to or more than 0,015 mm and equal to or less than 0,5 mm.

[0032] According to a second aspect of the present invention, there is provided an apparatus of the initially defined type, wherein the moulding tool is configured to press heated cellulose blank in a press-cavity delimited by said lower press-surface, said upper press-surface and said inner guide wall surface by applying a forming pressure P in the axial direction of the moulding tool for manufacturing cellulose products, and wherein a gap in the transversal direction between the inner guide wall surface and the outer guide wall surface is equal to or more than 0,015 mm and equal to or less than 0,5 mm.

[0033] The present invention is based on the insight / knowledge that there shall be no trimming of the discrete cellulose blank before pressing of the cellulose product and that the entire cellulose blank shall be pressed in order to prevent fibre release during the handling of the cellulose blank and of the cellulose product. Thereto the present invention is based on the insight / knowledge that the gap between the inner guide wall surface and the outer guide wall surface must not be too small, i.e. no less than 0,015 mm, since the risk of having a malfunctioning and / or damaged moulding tool due to colliding mould parts increases with accelerating rate when the gap decreases and thereto loosecellulose fibres will be more prone to become wedged in the gap if the gap decreases below 0,015 mm. Thereto the present invention is based on the insight / knowledge that the gap between the inner guide wall surface and the outer guide wall surface must not be too big, i.e. absolutely no more than 0,5 mm, since then the cellulose blank will inevitably be pushed up into the gap end the edge of the pressed cellulose product becomes frayed and sensitive to absorb moisture.

[0034] Thus, the inventor has developed an effective and reliable methodology for obtaining pressed cellulose products having intended shape and a distinct edge, wherein the pressed cellulose product in various embodiments obtains the final shape in the moulding tool and in various embodiments obtains the final shape in a subsequent trimming unit. The inventor has identified an optimal design and configuration of the moulding tool in order to obtain perfect cellulose products having distinct edge and less amount of loose fibres during the refining of the cellulose blank and of the cellulose product.

[0035] Thus, present invention provides the advantage that the pressing of the edge region in the moulding tool, i.e. pressing from three sides, provides optimal control of the sealing and location of the edge / rim and the amount of loose cellulose fibres is significantly reduced or eliminated.

[0036] According to various embodiments of the present invention, the discrete cellulose blank is constituted by an air-laid cellulose blank, wherein the step of providing a discrete cellulose blank, comprises the sub-steps of:

[0037] - providing a cellulose pulp sheet,

[0038] - disintegrating the cellulose pulp sheet in order to generate a quantity of separated cellulose fibres,

[0039] - transporting the separated cellulose fibres by an air flow to the cellulose blank forming unit, and - forming the discrete air-laid cellulose blank in the cellulose blank forming unit.

[0040] Thereby, the cellulose blank provided into the moulding tool is not cut out from a larger cellulose blank / web, but is formed into the correct / intended shape in the cellulose blank forming unit and thereby the scrap is minimized and the fibre dust release in connection with the moulding tool is reduced or eliminated.

[0041] According to various embodiments of the present invention, the apparatus comprises a trimming unit located downstream the product forming unit, the trimming unit comprising a seat having a guide edge, the method further comprises the step of:

[0042] - inserting the pressed cellulose product having the distinct edge into the trimming unit, wherein the distinct edge of the pressed cellulose product is positioned in engagement with the guide edge of the seat of the trimming unit, and

[0043] - cutting off scrap from the pressed cellulose product in the trimming unit.

[0044] Thereby, the pressed cellulose product is always oriented in the exact correct position in the trimming unit, and the final shape of the cellulose products after the trimming is identical for all products.Further advantages with and features of the invention will be apparent from the following detailed description of preferred embodiments.

[0045] Brief description of the drawings

[0046] A more complete understanding of the abovementioned and other features and advantages of the present invention will be apparent from the following detailed description of preferred embodiments in conjunction with the appended drawings, wherein:

[0047] Fig. 1 is a schematic illustration of a production line or apparatus for dry manufacturing rigid cellulose products,

[0048] Fig. 2 is a schematic illustration of a moulding tool according to a first embodiment, wherein a discrete cellulose blank is provided into the moulding tool between the first / female mould part and the second / male mould part,

[0049] Fig. 3 is a schematic illustration of the moulding tool according to figure 2 during forming / pressing of the cellulose product, i.e. the first mould part and the second mould part are in the press position,

[0050] Fig. 4 is a schematic illustration of the moulding tool according to figures 2 and 3 after the forming / pressing step and the pressed cellulose product is removed from the moulding tool,

[0051] Fig. 5 is a schematic illustration of the pressed cellulose product according to figure 4,

[0052] Fig. 6 is a schematic illustration of the first mould part according to a second embodiment in connection with removing the pressed cellulose product,

[0053] Fig. 7 is a schematic illustration of a moulding tool according to a second embodiment, wherein a discrete cellulose blank is provided into the moulding tool between the first / female mould part and the second / male mould part,

[0054] Fig. 8 is a schematic illustration of the moulding tool according to figure 7, wherein the first mould part and the second mould part are in the press position,

[0055] Fig. 9 is a schematic illustration of the pressed cellulose product according to figure 8, i.e. a clamp, in an open state from the side,

[0056] Fig. 10 is a schematic illustration of the pressed cellulose product according to figures 8-9, in a closed state from the side,

[0057] Fig. 11 is a schematic illustration of the pressed cellulose product according to figures 8-10, in a closed state in a perspective view, and

[0058] Fig. 12 is a schematic illustration of an apparatus for dry manufacturing rigid cellulose products, wherein the in-feed device provides the next cellulose blank into the moulding tool at the same time as the out-feed device removes the pressed cellulose product from the moulding tool.Detailed ion of embodiments of the invention

[0059] As used herein, the term "air / dry moulding / forming or air / dry laying / laid" means a well-known method according to which separated cellulose fibres are formed into a cellulose blank / web.

[0060] In air-laying technique, small / short fibres having a normal length in the range of 0,5 to 70 mm, for instance 1 to 10 mm, are separated and captured by an air stream / flow, and then laid on / applied to a forming mesh / surface, usually using a low pressure at the other side of the mesh / surface. The general terms "air / dry laying" and "air / dry moulding" are used interchangeably herein. The cellulose fibre carrying air flow may be generated by suitable device located upstream and / or downstream the forming mesh / surface.

[0061] Reference is initially made to figures 1 and 5, wherein figure 1 disclose a schematic illustration of a generic production line / apparatus for dry manufacturing rigid cellulose products, wherein said apparatus is generally designated 1. The production line 1 is configured for manufacturing rigid cellulose products, generally designated 2, having essentially non-flat general shape from separated cellulose fibres. Such a production line 1 may be arranged and set-up according to different well-known ways. Figure 5 disclose an example of a rigid cellulose product 2, i.e. a plate or tray. The apparatus 1 may have automatic transfer / handling between the different process steps, and / or may have manual transfer / handling between the different process steps, and thereto the apparatus 1 may have intermediate storing and / or additional process steps between the disclosed process steps, and / or the process steps may be located at different sites.

[0062] Figure 5 disclose an example of a rigid cellulose product 2 in the shape of a tray / plate, wherein the tray is formed using the inventive method. The tray 2 comprises an inclined circumferential wall 3 and an opening 4 defined by a circumferential rim / brim 5 connected to the upper / free end of the wall 3. According to figure 6 embodiment the brim 5 has a straight shape, however it shall be pointed out that the cross-section of the brim 5 may have other shapes. The tray 2 may have truncated cone shape having straight wall 3, narrowing in the direction away from the opening 4, in accordance with figure 6 embodiment. The tray 2 may for instance have curved-shaped wall 3 seen in the axial plane. By having inclined walls 3 multiple trays 2 are stackable one inside the other when they are empty. The tray could also be a lid, packaging or the like container / product. The cross section of the circumferential wall 3 in the radial plane may have any suitable shape, circular, oval, rectangular, polygonal, etc., and may differ in shape and / or dimension along the axial extension of the tray 2.

[0063] The tray 2 comprises a bottom 6, wherein the bottom 6 is entirely flat or the bottom may comprise local ribs, projections, etc., for strength and rigidity of the cellulose product 2. The bottom 6 may be located at the very lower end of the wall 3, according to figure 6 embodiment, and / or be partly located at an axial distance from the lower end of the wall 3, or a combination thereof. The circumferential wall 3 is connected to and extends in the axial direction upwards from the bottom portion 6. The general shape of the disclosed tray 2 is also applicable for a lid, cup, etc.

[0064] Cellulose raw material in the shape of continuous or discrete cellulose pulp sheet(s) 7, i.e. comprising mainly the cellulose part of organic matter, is provided to the production line, and is fedby a cellulose pulp sheet feeding unit to a separating / disintegrating unit 8 in order to obtain individualized / separated cellulose fibres. The separated cellulose fibres are thereafter transported by an air stream / flow to a dispenser of a cellulose blank / sheet forming unit 9. The cellulose fibres are laid by the dispenser on a moving or stationary perforated surface of the cellulose blank forming unit 9. The cellulose fibre carrying air flow may be generated by suitable device located upstream and / or downstream the perforated surface. Thereafter the generated cellulose blank, generally designated 10, is transported / transferred to a product forming unit 11, whereby rigid cellulose products 2 are formed and discharged from the product forming unit 11.

[0065] The cellulose blank forming unit 9 may be configured to generate a continuous cellulose blank / web 10 and / or discontinuous / discrete cellulose blanks 10. Discontinuous / discrete cellulose blanks 10 are fed into the product forming unit 11.

[0066] The cellulose raw material may be in the form of reeled pulp or paper, bale of cellulose pulp, paper, etc. and / or sheets of paper, cellulose pulp, etc. In case said cellulose raw material is in the form of sheets and / or reeled pulp, it can be fed directly into the separating unit 8. However, in case said cellulose raw material is in the form of a bale or compact stacks of sheets, etc. one or more shredders and / or one or more additional separating / disintegrating units may be necessary to be used for separating and dosing said cellulose raw material 7 from said bale or sheets into cellulose pulp sheet(s) 7. The separating unit 8 disintegrates the cellulose pulp sheet 7 into separated cellulose fibres.

[0067] Said cellulose raw material may be constituted by virgin cellulose fibres and / or recycled cellulose fibres and may originate from wood pulps such as kraft pulp, sulphite pulp, mechanical pulp, thermomechanical pulp (TMP), chemical treated mechanical pulp, chemi-thermomechanical pulp (CTMP), and / or from non-wood pulps such as bagasse, bamboo, abaca, hemp, flax, cotton.

[0068] The separating unit 8 may according to various embodiments be constituted by a hammer mill. In said separating unit 8 the cellulose pulp sheet 7 is separated into fibres having a normal length in the range of 0,5-70 mm, preferably less than 10 mm. The length of said fibres may be customized by adjusting the internal properties of the separating unit 8 and / or by choosing a different separating unit 8 and / or choosing different cellulose raw material. The fibre length for wood pulp is according to various embodiments in the range 0,5-4 mm, preferably in the range 1,7-3, 6 mm. According to various embodiments the fibre length for non-wood pulp is in the range 0,5-70 mm.

[0069] The production line 1 may comprise a pre-compression and / or imprinting unit 12, located downstream the cellulose blank forming unit 9 and upstream the product forming unit 11. In the precompression and / or imprinting unit 12, an air-laid fluffy cellulose blank 10 having a first thickness may be compressed into a cellulose blank 10 having a second thickness, wherein said second thickness is thinner than said first thickness, and / or may be provided with an imprinting pattern. During the pre-compression / imprinting the cellulose blank is made more coherent and easier to handle, since the pre-compression / imprinting generates internal bindings between individual cellulose fibres preventing mutual separation of the cellulose fibres.The product forming unit 11 comprises a press unit 13, and may optionally comprise a preheating unit 14 arranged upstream the press unit 13. According to various example embodiments said cellulose blank 10 may be heated to an elevated temperature before being fed into the press unit 13 of the product forming unit 11. In such embodiment(s) where the cellulose blank 10 is preheated before being fed into the press unit 13, said press unit 13 may or may not comprise heating. According to various example embodiment said press unit 13 may be a heated press unit 13 for heating said cellulose blank 10 during pressing. In the case of a heated press unit 13, preheating of said cellulose blank 10 using a pre-heating unit 14 is optional. According to various example embodiments preheating of the cellulose blank 10 in said pre-heating unit 14 may be combined with a heated press unit 13. Having a pre-heating unit 14 in combination with a heated press unit 13 will speed up the manufacturing process in the product forming unit 11, and improve the quality / rigidity of the final rigid cellulose product 2. In the product forming unit 11 the cellulose blank 10 is heated to a forming temperature T in the range 120 - 200 °C in order to obtain adequate rigidity and strength in the final cellulose product 2, preferably in the range 150-180 °C.

[0070] Reference is now made to figures 2-4. The press unit 13 comprises a moulding tool having a first mould part 15 and a second mould part 16 having co-operating designs, wherein at least one of the first mould part 15 and the second mould part 16 is / are displaceable in the axial direction in relation to each other, i.e. reciprocating back and forth in relation to each other, in order to exert pressure to the cellulose blank 10 loaded therebetween. In the figures the mutual displacement is disclosed as being vertical, however the mutual displacement may be horizontal or any other suitable angle. The cellulose blank 10 loaded into the moulding tool, is constituted by the air-laid discrete cellulose blank 10. The air-laid cellulose blank 10 may be generated upstream the product forming unit 11 in the same apparatus / production line and provided / transferred to the product forming unit 11, or may be generated at a separate location and provided / transferred to the product forming unit 11 via intermediate handling and storage.

[0071] According to various embodiments the first mould part 15 of the moulding tool is a female mould part, i.e. having a main recess 17 for receiving a major part of the cellulose blank 10, and the second mould part 16 of the moulding tool is a male mould part, i.e. having a main protrusion 18 for cooperation with said recess 17 of the female mould part by being inserted therein, such that the cellulose blank 10 is pressed into a final rigid non-flat shape by applying a predetermined forming pressure P in the axial direction of the moulding tool. According to the disclosed embodiment the male mould part 16 is located above the female mould part 15, i.e. the pressed cellulose product 2 is intended to be collected from the lower female mould part 15 after the pressing of the cellulose blank 10. However, according to an alternative to the disclosed embodiments the female mould part 15 may be located above the male mould part 16, i.e. the pressed cellulose product 2 is intended to be collected from the male mould part 16 after the pressing of the cellulose blank 10. Thus, it is preferred that the pressed cellulose product 2 is intended to remain in / on the lower mould part after the pressing of the cellulose product 2. When the moulding tool has horizontal pressing direction,the pressed cellulose product 2 may be automatically removed / ejected from the moulding tool when the moulding tool is opened after the pressing of the cellulose blank 10.

[0072] The male / second mould part 16 comprises a product press-surface or upper press-surface, generally designated 19. In the disclosed example embodiment, the upper press-surface 19 of the second mould part 16 comprises a bottom surface 20, a wall surface 21 connected to the bottom surface 20 and extending essentially in the axial direction, and a brim surface 22 connected to the wall surface 21 and extending essentially in the transversal / radial direction. The female / first mould part 15 comprises a product press-surface or lower press-surface, generally designated 23. In the disclosed example embodiment, the lower press-surface 23 of the first mould part 15 comprises a bottom surface 24, a wall surface 25 connected to the bottom surface 24 and extending essentially in the axial direction, and a brim surface 26 connected to the wall surface 25 and extending essentially in the transversal / radial direction. The lower press-surface 23 of the first mould part 15 and the upper press-surface 19 of the second mould part 16 are arranged opposite each other. When the moulding tool comprises only product press-surfaces facing in the axial direction, it is configured to press / form a cellulose product 2 in its final shape without need for trimming off scrap material.

[0073] According to alternative embodiments, the moulding tool comprises scrap press-surfaces located adjacent the upper press-surface 19 and the lower press-surface 23, respectively. According to various embodiments, the scrap press-surfaces of the mould parts entirely surrounds the corresponding product press-surface, and according to other embodiments, the scrap press-surfaces of the mould parts is only located at some locations around the corresponding product press-surface. The scrap press-surface of the first mould part 15 is arranged opposite the scrap press-surface of the second mould part 16.

[0074] The cellulose blank 10 is pressed between the surfaces of the male / second mould part 16 and the surfaces of the female / first mould part 15 into final shape. The mutual distance, taken perpendicular to the surface in question, between the product press-surface 23 of the first mould part 15 and the product press-surface 19 of the second mould part 16 during the pressing of the cellulose blank 10 into a cellulose product 2 is X millimetres, wherein X preferably is in the range 0,2-3,0 millimetres, i.e. equal to the thickness of the bottom 6 of the pressed cellulose product 2.

[0075] Preferably, X is in the range 0,25-1,5 millimetres. The wall surfaces 21, 25 of the moulding tool has to be inclined in order to obtain a release angle for the cellulose product 2, and in order to obtain adequate press force to the wall region 3 of the cellulose product 2.

[0076] According to embodiments comprising scrap press-surfaces, the mutual distance between the scrap press-surface of the first mould part 15 and the scrap press-surface of the second mould part 16 is preferably equal to the mutual distance between the product lower press-surface 23 of the first mould part 15 and the upper press-surface 19 of the second mould part 16. The part of the cellulose blank 10 located at the scrap area may partially compressed by applying a predetermined partial pressure less than said predetermined forming pressure P, be compressed by applying said predetermined forming pressure P, or be additionally compressed by applying a pressure greaterthan the predetermined forming pressure P. Thus, radially outside the final rigid cellulose product 2, the cellulose blank 10 may comprises a scrap area intended to be cut off. In figure 4 the cellulose product 2 is released and schematically removed from the moulding tool by opening the moulding tool. Figure 5 disclose a schematic illustration of a cellulose tray 2.

[0077] The predetermined forming pressure P is in the range 40-10000N / cm2, preferably in the range 100-4000N / cm2. According to various embodiments said predetermined pressures are above 500 N / cm2, and according to various embodiments said predetermined pressures are below 2500 N / cm2. The holding time during the pressing step is in equal to or more than 0,5 seconds and equal to or less than 10 seconds, preferably less than 5 seconds, and most preferably less than 3 seconds.

[0078] According to various embodiments. Before any items / food is placed in the cellulose product 2 or before the cellulose product is used, for instance when the inside of the cellulose product 2 is exposed to moist / grease during use, the rigid cellulose product 2 may be provided with a liner film adhered to at least to the circumferential rim / brim 5, and preferably also to the wall 3 and / or the bottom 6 of the cellulose product 2. The liner film may be constituted by a multilayer film comprising polymer and / or metal. The adhesion of the liner film to the cellulose product is preferably heat activated.

[0079] According to various embodiments, the cellulose blank 10 may comprise barrier additives and / or material property enhancing additives, etc., such that the rigid cellulose tray 2 withstand grease, fat, water, vapour, etc. The additives are preferably provided to the cellulose fibers upstream the disintegrating unit 8 or between the disintegrating unit 8 and the product forming unit 11.

[0080] According to various embodiments. When the compartment of the rigid cellulose product 2 is filled with objects, a film / cover / lid may be attached to the circumferential rim / brim 5 of the cellulose tray 2, for instance using heat lamination. The lid film may be constituted by a multilayer film comprising polymer, metal, and / or paper.

[0081] According to various embodiments, the moisture content of the cellulose blank 10 provided into the moulding tool is in the range 5-20 wt%, preferably in the range 6-13 wt%. A too low moisture content entails that the internal bonding in the thermoformed / pressed cellulose product 2 are not strong enough and the risk of blistering / delamination of the cellulose product 2 during opening of the moulding tool is increased, and the risk for cracks is increased. A too high moisture content entails that the amount of water that is heated is increased and the risk of steam explosion / expansion during opening of the moulding tool is increased, that may lead to blistering / delamination and cracks.

[0082] According to the present invention, the first mould part 15 comprises the lower press-surface 23 and a cylinder-shaped inner guide wall surface 27 located adjacent to and extending in the axial direction from the lower press-surface 23 of the first mould part 15, i.e. from the periphery of the lower press-surface 23, wherein the cylinder-shaped inner guide wall surface 27 defines a guide chamber 28. Further, the second mould part 16 comprises the upper press-surface 19 and a cylindershaped outer guide wall surface 29 located adjacent to and extending in the axial direction from theupper press-surface 19 of the second mould part 16, i.e. from the periphery of the upper presssurface 19, wherein the cylinder-shaped outer guide wall surface 29 defines a guide body 30. The cross-section of the outer guide wall surface 29 corresponds to the cross-section of the inner guide wall surface 27, i.e. the shape and size of the transversal cross-section of the guide body 30 corresponds to the shape and size of the transversal cross-section of the guide chamber 28. Thus, the upper press-surface 19 constitute the distal end of the guide body 30 of the male / second mould part 16. The first mould part 15 and the second mould part 16 are preferably rigid elements, i.e. does not comprise any deformable mould part elements.

[0083] According to various embodiments the apparatus 1 further comprises a male pre-shaping part, not disclosed, configured for pre-shaping the cellulose blank 10 in the main recess 17 of the first mould part 15 before the pressing of the cellulose blank 10 into final shape. The male pre-shaping part is introduced into the moulding tool, for instance by means of an automated / mechanical arm. The male pre-shaping part is different from the second / male mould part 16. The pre-shaping of the cellulose blank 10 is realized by insertion of the male pre-shaping part into the main recess 17 of the first / female mould part 15 having the cellulose blank 10 located therebetween. During the preshaping step, the cellulose blank 10 is subject to plastic deformation due to the weak connection between the separate cellulose fibres in the cellulose blank 10, but the essentially uniform thickness of the cellulose blank 10 is maintained since the cellulose blank 10 is wrapped about the male preshaping part without entailing any extensive material draw and elongation. Thus, when the male preshaping part is retracted, the pre-shaped cellulose blank 10 will stay in the pre-shaped shape / position in the main recess 17 of the first / female mould part 15. The general shape of the male pre-shaping part is preferably corresponding to the general shape of the first mould part 15, but the cellulose blank 10 is not pressed between the male pre-shaping part and the first mould part 15 during the pre-shaping step. It is vital that the shape of the pre-shaped cellulose blank 10 is configured to receive the main protrusion 18 of the second mould part 16 without involving deformation / creasing of the wall regions of the pre-shaped cellulose blank 10.

[0084] According to various embodiments, the male pre-shaping part, in connection with at least a bottom surface thereof, comprises holding means configured for fixating the cellulose blank 10 in relation to the male pre-shaping part during the insertion of the male pre-shaping part into the main recess 17 of the first mould part 15. Thereby the cellulose blank 10 is prevented from material draw and elongation during the insertion of the cellulose blank 10 into the molding tool.

[0085] After the pre-shaping of the cellulose blank 10 the male pre-shaping part is removed from the moulding tool and the cellulose blank 10 is pressed between the first mould part 15 and the second mould part 16 into final shape.

[0086] The moulding tool is configured to press heated cellulose blank 10 in a press-cavity delimited by said lower press-surface 23, said upper press-surface 19 and said inner guide wall surface 27 by applying a forming pressure P in the axial direction of the moulding tool for manufacturing cellulose products, and wherein a gap Y in the transversal direction between the inner guide wall surface 27and the outer guide wall surface 29 is equal to or more than 0,015 mm and equal to or less than 0,5 mm. Preferably the gap Y in the transversal direction between the inner guide wall surface 27 and the outer guide wall surface 29 is equal to or more than 0,02 mm and equal to or less than 0,2 mm. The gap Y may be measured / determined as the total play in the transversal direction between the inner guide wall surface 27 and the outer guide wall surface 29 divided by two, and the gap Y is measured perpendicular to said surfaces. It shall be realized that the gap Y is the nominal distance between the surfaces, i.e. the surfaces may comprise minor irregularities due to manufacturing tolerances.

[0087] According to various embodiments, the apparatus 1 comprises a trimming unit 31 located downstream the product forming unit 13, the trimming unit 31 comprising a seat having a guide edge, the method further comprises the step of:

[0088] - inserting the pressed cellulose product 2 having the distinct edge into the trimming unit 31, wherein the distinct edge of the pressed cellulose product 2 is positioned in engagement with the guide edge of the seat of the trimming unit 31, and

[0089] - cutting off scrap from the pressed cellulose product 2 in the trimming unit 31.

[0090] Thus, the guide edge of the seat of the trimming unit 31 is configured to position and orient the cellulose product 2 such that the cutting / trimming takes place at the exact correct location and the final cellulose products 2 have identical shape. Since the scrap material that is cut off is pressed, there is no loose fibers contaminating the environment, when handling the scrap material. The trimming unit 31 preferably comprises a shear-cut arrangement.

[0091] Reference is now made to figure 6, disclosing the first mould part 15 according to a second embodiment. The lower press surface 23 of the first mould part 15 is displaceable in the axial direction in relation to the inner guide wall surface 27. The lower press surface 23 is displaced towards the second mould part 16 in connection with the step of removing the pressed cellulose product 2 from the moulding tool. Thus, the lower press surface 23 lifts the pressed cellulose product 2 to the upper part of the guide chamber 28 in order to make it easier to engage the cellulose product 2 using an out-feed device 32.

[0092] Reference is now made to figures 7-11 disclosing a pressed cellulose clamp 2 from the side in open and closed configuration, respectively, and in a perspective view. The disclosed clamp 2 is a travel protection for a pump bottle dispenser, i.e. the clamp is located around the stem of the pump such that the pump head cannot be pushed down by mistake during transportation.

[0093] Figures 7 and 8 disclose a second schematic embodiment of the product forming unit 13, and corresponds to figures 2 and 3. Everything referring to the product press-surfaces of the moulding tool, is the same for all embodiments covered by the present invention. The description hereinbelow refereeing to the second embodiment disclosed in figures 10-14, will mainly focus on differences between the second embodiment, figures 10-14, and the first embodiment, figures 2-6.

[0094] The first mould part 15 and the second mould part 16, does not comprise any scrap presssurface. Thus, the entire discrete cellulose blank 10 that is captured between the first mould part 15and the second mould part 16, when they are displaced in the axial direction in relation to each other will become pressed and converted into the pressed cellulose product 2.

[0095] According to the disclosed second embodiment of the rigid cellulose product 1, the clamp is formed using the inventive method. The cellulose clamp 2 comprises a first part 2a and a second part 2b. The first part 2a and the second part 2b are essentially alike except for a snap member 33 and the outer flange 34. The first part 2a comprises a bottom 6, an opening 4 and a brim 5, wherein the brim 5 is connected to the bottom portion 6. The bottom 6 may alternatively be considered a wall. According to alternative embodiments, the bottom 6 may for instance be V-shaped or shaped as one half of a hexagonal. The second part comprises a bottom 6', an opening 4' and a brim 5', wherein the brim 5' is connected to the bottom portion 6'. The bottom 6' may alternatively be considered a wall. According to alternative embodiments, the bottom 6' may for instance be V-shaped or shaped as one half of a hexagonal, or be entirely flat.

[0096] The cellulose clamp 2 comprises a hinge or fold line 35, dividing / connecting the first part 2a and the second part 2a. The hinge or fold line 35 may be pressed and / or partly cut / perforated. The moulding tool comprises a hinge arrangement 36 in order to generate the fold line 35 of the cellulose product 2. The hinge arrangement 36 may for instance be constituted by a nip that is configured to generate a waist-shaped bridge between the container part 2a and the lid part 2a, or be constituted by press-surfaces having corresponding shape and configured to generate a small arc-shaped bridge between the container part 2a and the lid part 2b, as seen in the disclosed embodiment.

[0097] The cellulose product 2 further comprises a snap member 33, connected to the rim 5' of the second part 2b or connected to the rim 5 of the first part 2a. According to the disclosed embodiment, the snap member 33 is connected to the rim 5' of the second part 2b, wherein the snap member 8 is configured to cooperate with the rim 5 of the first part 2a, when the cellulose clamp 2 is closed. Thus, the undercut feature is constituted by the snap member 8 together with the adjacent rim. The rim 5' of the second part 2b is configured to abut the rim 5 of the first part 2a when the cellulose clamp 2 is closed.

[0098] Reference is now made to figure 12 disclosing a schematic illustration of the apparatus 1 for dry manufacturing rigid cellulose products 2, the apparatus 1 comprising an inventive product forming unit 11.

[0099] The apparatus 1 comprises a conveyor arrangement, generally designated 37. The conveyor arrangement 37 is configured to receive cellulose blanks 10 in a continuous stream from the cellulose blank forming unit 9, and transporting the continuous stream of cellulose blanks 10 in a transport direction towards the product forming unit 11. The separating / disintegrating unit 8 and the cellulose blank forming unit 9 are schematically disclosed, at the upstream end of the conveyor arrangement 37. According to alternative embodiments the cellulose blanks 10 are provided to the conveyer arrangement 36 from an intermediate storage, manually or automatically.

[0100] The conveyor arrangement 37 comprises an endless conveyor belt 38 that according to the disclosed embodiment is continuously moving during operation of the apparatus 1, and has apredetermined traveling speed in the transport direction of the conveyor arrangement 37. The traveling speed of the conveyor belt 38 is preferably adjustable, and is adjusted in consensus with the cycle rate of the product forming unit 11, and also in consensus with the cycle rate of the cellulose forming unit 9 when applicable. The traveling speed of the conveyor belt 38 is also dependent on the size of the cellulose blanks 10 in relation to the size of the mutual gap between the cellulose blanks 10. According to alternative embodiments, the conveyor belt 38 may be intermittently / stepwise moving, in order to receive cellulose blanks 10 and in order to transfer cellulose blanks towards the product forming unit 11.

[0101] The apparatus 1 further comprises an in-feed device, generally designated 39, configured for transferring the cellulose blank 10 from the conveyor arrangement 37 and loading the cellulose blank 10 into the moulding tool that is open and empty. The in-feed device 39 preferably comprises a suction device configured to engage and transfer the cellulose blank 10 from the continuously moving conveyor belt 38 into the open moulding tool. About the same time as the in-feed device 39 engages the cellulose blank 10, the preceding press cycle in the product forming unit 11 is finished and the moulding tool of the product forming unit 11 is opened.

[0102] In figure 12, the in-feed device 39 transfers the cellulose blank 10 into the moulding tool, and concurrently the pressed cellulose product 2 from the preceding press-cycle is removed from the moulding tool. The in-feed device 39 releases the cellulose blank 10 in the open moulding tool. According to various embodiments, the in-feed device 39 is configured to pre-form the discrete cellulose blank 10 in the first mould part 15, i.e. by arranging the discrete cellulose blank 10 in contact with the lower press-surface 23 of the first mould part 15.

[0103] The pressed cellulose product 2 is removed from the moulding tool by means of the out-feed device 32. The out-feed device 32 is configured to remove the pressed cellulose product 2 from the moulding tool in order to make the moulding tool empty and ready for the loading of the next cellulose blank 10. Thus, part of the out-feed device 32 is insertable into the moulding tool between the male / second mould part 16 and the female / first mould part 15 after the pressing of the cellulose blank 10. Thus, the pressed cellulose product 2 is intended to be located in / on the first mould part 15 after the pressing of the cellulose blank 10, and after the moulding tool is opened. Thereto, the out-feed device 32 may be arranged to transfer the pressed cellulose product 2 to a subsequent step in the apparatus such as the cutting / trimming unit 31 and / or stacking station.

[0104] The inventive method comprises the general steps of:

[0105] - providing a discrete cellulose blank 10,

[0106] - transferring the discrete cellulose blank 10 into the moulding tool, by inserting the discrete cellulose blank 10 into the guide chamber 28 of the first mould part 15,

[0107] - closing the moulding tool by telescopically inserting the guide body 30 of the second mould part 16 into the guide chamber 28 of the first mould part 15,- pressing the heated cellulose blank 10 by applying a forming pressure P in the axial direction of the moulding tool, wherein the cellulose blank 10 is pressed in a press-cavity delimited by said lower press-surface 23, said upper press-surface 19 and said inner guide wall surface 27,

[0108] - displacing at least one of the first mould part 15 and the second mould part 16 in the axial direction in relation to each other, away from each other, and

[0109] - removing the pressed cellulose product 2 having a distinct edge from the moulding tool.

[0110] Thus, since the steps of the inventive method are listed in the order they occur, it is clear that the cellulose blank 10 is inserted into the guide chamber 28 of the female mould part 15, thereafter the moulding tool is closed by telescopically inserting the guide body 30 of the male mould part 16 into the guide chamber 28 of the female mould part 15, and thereafter the cellulose blank 10 is pressed between the upper press-surface 19 and the lower press-surface 23 and the inner guide wall surface 27.

[0111] According to various embodiments, the step of providing an air-laid discrete cellulose blank 10, comprises the sub-steps of:

[0112] - providing a cellulose pulp sheet 7,

[0113] - disintegrating the cellulose pulp sheet 7 in order to generate a quantity of separated cellulose fibres,

[0114] - transporting the separated cellulose fibres by an air flow to a cellulose blank forming unit 9, and - forming the discrete air-laid cellulose blank 10 in the cellulose blank forming unit 9.

[0115] Thereby, the discrete cellulose blank 10 provided into the moulding tool is not cut out from a larger cellulose blank / web, but is formed into the correct / intended shape in the cellulose blank forming unit 9 and thereby the scrap is minimized and the fibre dust release in connection with the moulding tool is reduced or eliminated.

[0116] Feasible modifications of the Invention

[0117] The invention is not limited only to the embodiments described above and shown in the drawings, which primarily have an illustrative and exemplifying purpose. This patent application is intended to cover all adjustments and variants of the preferred embodiments described herein, thus the present invention is defined by the wording of the appended claims and the equivalents thereof. Thus, the equipment may be modified in all kinds of ways within the scope of the appended claims. Any subject matter falling outside the scope of the claims is provided for information purposes, and for placing the invention into a relevant context.

[0118] It shall also be pointed out that all information about / concerning terms such as above, under, upper, lower, etc., shall be interpreted / read having the equipment oriented according to the figures, having the drawings oriented such that the references can be properly read. Thus, such terms only indicate mutual relations in the shown embodiments, which relations may be changed if the inventive equipment is provided with another structure / design.It shall also be pointed out that even thus it is not explicitly stated that features from a specific embodiment may be combined with features from another embodiment, the combination shall be considered obvious, if the combination is possible.

[0119] Throughout this specification and the claims which follows, unless the context requires otherwise, the word "comprise", and variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated integer or steps or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps.

Claims

Claims1. Method for dry manufacturing rigid cellulose products (2) having essentially non-flat general shape from a discrete cellulose blank (10), wherein the method is performed in an apparatus (1) comprising a cellulose blank forming unit (9) and a product forming unit (11) having a moulding tool and heating means for heating the discrete cellulose blank (10) to a forming temperature T, wherein the moulding tool comprises a first mould part (15) and a second mould part (16),- the first mould part (15) comprises a lower press-surface (23) and a cylinder-shaped inner guide wall surface (27) located adjacent to and extending in the axial direction from the lower presssurface (23) of the first mould part (15), wherein the cylinder-shaped inner guide wall surface (27) defines a guide chamber (28),- the second mould part (16) comprises an upper press-surface (19) and a cylinder-shaped outer guide wall surface (29) located adjacent to and extending in the axial direction from the upper press-surface (19) of the second mould part (16), wherein the cylinder-shaped outer guide wall surface (29) defines a guide body (30), the cross-section of the outer guide wall surface (29) corresponding to the cross-section of the inner guide wall surface (27),the method comprising the steps of:- providing a discrete cellulose blank (10),- transferring the discrete cellulose blank (10) into the moulding tool, by inserting the discrete cellulose blank (10) into the guide chamber (28) of the first mould part (15),- closing the moulding tool by telescopically inserting the guide body (30) of the second mould part (16) into the guide chamber (28) of the first mould part (15),- pressing the heated cellulose blank (10) by applying a forming pressure P in the axial direction of the moulding tool, wherein the cellulose blank (10) is pressed in a press-cavity delimited by said lower press-surface (23), said upper press-surface (19) and said inner guide wall surface (27), - displacing at least one of the first mould part (15) and the second mould part (16) in the axial direction in relation to each other, away from each other, and- removing the pressed cellulose product (2) having a distinct edge from the moulding tool, wherein a gap (Y) in the transversal direction between the inner guide wall surface (27) and the outer guide wall surface (29) is equal to or more than 0,015 mm and equal to or less than 0,5 mm.

2. The method according to claim 1, wherein the discrete cellulose blank (10) is constituted by an airlaid cellulose blank (10), wherein the step of providing a discrete cellulose blank (10), comprises the sub-steps of:- providing a cellulose pulp sheet (7),- disintegrating the cellulose pulp sheet (7) in order to generate a quantity of separated cellulose fibres,- transporting the separated cellulose fibres by an air flow to the cellulose blank forming unit (9), and - forming the discrete air-laid cellulose blank (10) in the cellulose blank forming unit (9).

3. The method according to any preceding claim, wherein the forming pressure P is in the range 0,4-100 MPa, preferably in the range 5-25 MPa.

4. The method according to any preceding claim, wherein the forming temperature T is in the range 120 - 200 °C, preferably in the range 150-180 °C.

5. The method according to any preceding claim, wherein the step of pressing the heated cellulose blank (10) is performed during a pressing time duration in the range 0,5-10 seconds, preferably in the range 0,5-5 seconds.

6. The method according to any preceding claim, wherein the moisture content of the cellulose blank (10) provided into the moulding tool is in the range 5-20 wt%, preferably in the range 6-13 wt%.

7. The method according to any preceding claim, wherein the apparatus (1) comprises a trimming unit (31) located downstream the product forming unit (11), the trimming unit (31) comprising a seat having a guide edge,the method further comprises the step of:- inserting the pressed cellulose product (2) having the distinct edge into the trimming unit (31), wherein the distinct edge of the pressed cellulose product (2) is positioned in engagement with the guide edge of the seat of the trimming unit (31), and- cutting off scrap from the pressed cellulose product (2) in the trimming unit (31).

8. The method according to claim 7, wherein trimming unit (31) comprises a shear-cut arrangement.

9. The method according to any preceding claim, wherein the lower press surface (23) of the first mould part (15) is displaceable in the axial direction in relation to the inner guide wall surface (27), and is displaced towards the second mould part (16) in connection with the step of removing the pressed cellulose product (2) having a distinct edge from the moulding tool.

10. An apparatus (1) for dry manufacturing rigid cellulose products (2) having essentially non-flat general shape from a discrete cellulose blank (10), wherein the apparatus (1) comprises a cellulose blank forming unit (9) and a product forming unit (11) having a moulding tool and heating means for heating the discrete cellulose blank (10) to a forming temperature T, wherein the moulding tool comprises a first mould part (15) and a second mould part (16),- the first mould part (15) comprises a lower press-surface (23) and a cylinder-shaped inner guide wall surface (27) located adjacent to and extending in the axial direction from the lower press-surface (23) of the first mould part (15), wherein the cylinder-shaped inner guide wall surface (27) defines a guide chamber (28), and- the second mould part (16) comprises an upper press-surface (19) and a cylinder-shaped outer guide wall surface (29) located adjacent to and extending in the axial direction from the upper press-surface (19) of the second mould part (16), wherein the cylinder-shaped outer guide wall surface (29) defines a guide body (30), the cross-section of the outer guide wall surface (29) corresponding to the cross-section of the inner guide wall surface (27),wherein the moulding tool is configured to press heated cellulose blank (10) in a press-cavity delimited by said lower press-surface (23), said upper press-surface (19) and said inner guide wall surface (27) by applying a forming pressure P in the axial direction of the moulding tool for manufacturing cellulose products (2), andwherein a gap (Y) in the transversal direction between the inner guide wall surface (27) and the outer guide wall surface (29) is equal to or more than 0,015 mm and equal to or less than 0,5 mm.

11. The apparatus (1) according to claim 10, wherein the gap (Y) in the transversal direction between the inner guide wall surface (27) and the outer guide wall surface (29) is equal to or more than 0,02 mm and equal to or less than 0,2 mm.

12. The apparatus (1) according to claim 10 or 11, wherein the apparatus (1) further comprises: - a cellulose pulp sheet feeding unit,- a disintegrating unit (8) for providing a quantity of separated cellulose fibres from the cellulose pulp sheet (7), and- a cellulose blank forming unit (9) for forming a discrete air-laid cellulose blank (10) from said quantity of separated cellulose fibres transported by an air flow from the disintegrating unit (8).

13. The apparatus (1) according to any of claims 10-12, wherein the first mould part (15) and the second mould part (16) are rigid element.

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