Press molding method for textile products and textile products

Abstract

The present invention relates to a method for press-forming pre-formed press-molded textile products, which are formed under high pressure and high temperature using a press pad device (9) and a stamping device. The press pad device (9) has an opening space (91) having a bottom (94) and a wall (92), and the stamping device has a fitting shape that forms a gap between products relative to the press pad device (9). The textile products (1,5) are manufactured by forming a sheet-like blank (8) made of an integrated fiber network, which is obtained by cutting from a raw material sheet made of an integrated fiber network, within the gap between products; that is, the blank (8) is formed into the textile products (1,5) after press-forming. The blank (8) is provided with at least one excess portion (82). This at least one excess portion (82) is pushed into an adjacent portion of the blank (8) before or during pressing and integrated into at least one reinforcing portion (3) of the textile products (1,5).

Description

Technical Field

[0001] The present invention relates to a press molding method for manufacturing a fiber product by using, as a raw material, a sheet-like blank made of an integrated fiber network and molding it under high pressure and high temperature using a press pad device and a stamp device.

Background Art

[0002] It is known from Patent Document 1 and Patent Document 2 that fiber products can be manufactured by pressing various types of raw materials such as wood chips. However, the present invention belongs to a different technical field, namely the field of using a web or sheet of fibers made of an integrated fiber network. Usually, a combination of natural fibers (such as wood pulp fibers) and synthetic fibers (such as polyolefin fibers such as polyethylene), and additives such as binders and dyes are used. In many applications, such a web is preferably composed substantially only of natural fibers, regardless of the presence or absence of additives. Typical molding conditions are a pressure of 150 to 250 °C and 100 to 10,000 bar (usually 200 to 2,000 bar), and the moisture content is often usually less than 20%, which is disclosed in Patent Document 3 and Patent Document 4.

[0003] The fiber product can be formed as a hollow product, such as a package or a lid (lid, screw cap, etc.), or it can be a flat product. The product is formed from a web of material and may be punched or cut simultaneously with the molding. That is, in order to facilitate the molding, the material may be completely or partially separated from the web. This processing is usually performed by cutting out the material in a shape that conforms to the final shape. For example, it is typical to cut out a circular blank to form a round package.

[0004] Press forming is typically performed using two tools: an outer tool pad and an inner tool (stamp), which may consist of several parts to facilitate removal of the finished product. Generally, the pad opens and the stamp contracts. The piston, or part of it, or part of the pad, can also be made of a compressible material, which allows the tool material to deform during compression, thereby applying a greater vertical compressive force to the sides of the cavity.

[0005] Further examples of known methods like those described above are shown in Patent Documents 5 and 6. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] U.S. Patent No. 4248820 [Patent Document 2] International Publication No. 2009 / 132318 [Patent Document 3] International Publication No. 2018 / 013397 [Patent Document 4] U.S. Patent No. 4227710 [Patent Document 5] European Patent Application Publication No. 3736099 [Patent Document 6] International Publication No. 2020 / 165780 [Overview of the project]

[0007] The object of the present invention is to optimize, with respect to the molded press-formed fiber product described in the independent claim, in terms of strength for a specific application.

[0008] According to the present invention, a reinforced pre-formed press-molded textile product can be obtained cost-effectively while reducing the amount of raw materials used. In particular, unlike the folded reinforcement parts of conventional textile products, the present invention is superior in that it can form a reinforcement part in which the fiber network is advantageously integrated by the principle of forming the reinforcement part by a pressing operation. That is, it is possible to optimize the fiber network and form the reinforcement part before and / or during pressing. [Brief explanation of the drawing]

[0009] The present invention will be described below with reference to preferred embodiments of a flat, pre-formed press-molded fiber product.

[0010] [Figure 1] This shows a perspective view of a pre-formed press-molded textile product used as a bottle holder according to the present invention. [Figure 2] A cross-sectional view along section AA of Figure 1 is shown. [Figure 3] This shows a top view of a pre-formed press-molded lid according to the present invention. [Figure 4] Figure 3 shows a cross-sectional view along the BB section. [Figure 5] The image shows a top view of a preferred pre-cut raw material used to manufacture the lid shown in Figures 3 and 4 according to the present invention. [Figure 6] Figures 3 and 4 show schematic cross-sectional views of a mold for manufacturing the lid shown in the present invention. [Modes for carrying out the invention]

[0011] As will be understood by those skilled in the art, the present invention is based on the use of a textile press die (not shown) for forming textile products. The die comprises a press pad device and a stamping device. The stamping device may be a single unit, divisible into two or more parts, or scalable. The press pad device comprises a body having at least one cavity, the body 20 may be a single unit or divisible into two or more parts. The stamping member has a body configured to fit into the cavity, and is configured such that a gap is formed between its side surface and the side wall of the cavity. This makes it possible to obtain a side wall of a desired thickness, and further, by pressing to a predetermined distance during pressing, it is possible to form flat and / or curved portions of the textile product having a desired thickness.

[0012] The material for the textile product 1 includes natural fibers and / or recycled wood fibers such as wood, straw, and bagasse, or a combination thereof, and is preferably composed of natural wood fibers, more preferably unused natural wood fibers. Furthermore, when sustainability is important, it is preferable to use recycled wood fibers. The raw material is preferably a sheet in which the amount of fiber is uniformly distributed in each cross-section and has a substantially constant thickness, and a blank is cut out from this sheet and used in a subsequent pressing process. The moisture content in the pre-cut blank (e.g., a circular blank) before pressing is preferably not more than 20% of the fiber weight. The molding temperature is in the range of 150 to 250°C, and the pressure applied by the stamp 3 and additional stamping device 4 is at least 200 bar. Furthermore, the pressurization can be performed in the range of approximately 500 to approximately 1,000 bar.

[0013] Figure 1 shows an example of a product manufactured according to the present invention. The illustrated bottle holder 1 has multiple openings 35 that form multiple holder portions H for holding the neck of a bottle, and further has two holes 4 for carrying the bottle holder 1. The bottle holder has a support portion 2 made of cellulose fibers according to the dry molding process described above. The bottle holder 1 has reinforcing members 3 for improving the strength properties in predetermined areas. These predetermined areas can be located in various positions depending on the type of product. The basic principle for forming the reinforcing members is to place more fibers in the areas that form the reinforcing members 3. This is achieved by rearranging the fibers in the raw material and moving the fibers to desired specific areas.

[0014] Therefore, in the illustrated embodiment, the amount of fiber is increased laterally in the desired region forming the reinforcing member 3 by removing the fibrous material from the region forming the openings 35,4 in the final product and moving those fibers laterally within the fiber layer. This can be achieved, for example, by providing a protruding through portion corresponding to the shape of the opening in the final product; for example, the hole 4 can be circular, and the bottle holder H can be a part of a circle. As a result, the reinforcing member 3 is formed to have a reinforcing body 30 that is thicker than the main body 20 of the support portion 2, and can have an outer edge 32 that constitutes a transition region and a more rounded inner edge 31. Preferably, the semi-closed opening 35 is positioned with its peripheral edge 34 compressed, thereby providing additional strength and / or abrasion resistance.

[0015] Figure 2 shows a cross-sectional view along line AA in Figure 1, which shows that the support 20 has a thickness t1 smaller than the thickness t2 within the reinforcing body 30 of the reinforcing member 3. The width W of the reinforcing body 30 is limited in this case. The width W can be used to control both the density and thickness t2 of the reinforcing body 30. In the illustrated embodiment, all fibers present in the regions of the opening H and holes 4 in the blank of the bottle holder 1 before pressing are extruded into adjacent regions, and these fibers are integrated to form a reinforcing member 3 with a reinforcing body 30 having more fibers and a larger thickness t2. By extruding the fibers from the opening, the strength in the reinforced region 3 is improved. The thickness t2 and width W of the reinforcing member 3 can be controlled by controlling the size of the pressing member (not shown). Therefore, if a smaller thickness t2 is selected, the density will be even higher. Thus, regardless of whether the support 20 and the reinforcing body 30 of the reinforcing member 3 have the same density or not, the strength of the reinforcing member 3 is increased by the amount of fiber. The actual fiber content is determined by measuring the cross-section of the product using microscopic images and (e.g., computer-aided) analysis, and comparing the fiber content within a certain distance, for example, within the total width W of the reinforcing member 30, with the fiber content of adjacent supports 20 within the same distance (i.e., W). As is clear, a similar function is obtained in the holes 4 for carrying the bottle holder 1. Therefore, reinforcing members 3 are also formed around the holes 4, thereby improving strength and comfort when carrying the bottle holder 1. In a more preferred embodiment, the reinforcing member 3 has a curved portion, for example, semicircular or circular.

[0016] Figures 3 and 4 show another embodiment of the present invention, shown here as a lid 5 used for a cup. The lid 5 is provided with an opening 6 for drinking and a hole 7 for introducing air into the cup when drinking. According to known methods, the lid 5 is equipped with a U-shaped collar 50 for snapping onto the upper rim of the cup.

[0017] Figure 4 shows a cross-sectional view of the lid 5 along line B-B. It can be seen that the cross-section line passes through a plurality of reinforcing members 3. The reinforcing members 3 are arranged within the outer collar portion 50. These reinforcing bodies 33 have the same thickness as the other parts of the lid, but more fibers are compressed within their volume. Therefore, this part 33 has a higher density than most of the other main body parts of the support portion 2 of the lid. Similarly, a more highly dense compression part 34 is formed around the cutout hole 7, and it is also shown that a corresponding compression part 35 is formed around the drinking opening 6.

[0018] Figure 5 shows a suitable type of pre-cut blank 8 used for manufacturing the lid 5 shown in FIGS. 3 and 4. As shown, the shape of the raw material 8 is polygonal, preferably hexagonal, and a plurality of pre-cut raw material pieces 8, 8' can be cut out without waste in an adjacent arrangement from a wide raw material sheet. As the raw material of the pre-cut blank 8, a sheet in which the fiber amount is uniformly distributed and has a substantially constant thickness in each cross-sectional part used is preferred, whereby all parts have substantially the same density. Also, the part that forms the lower end 51 of the lid in the final product is indicated by a marking 51, and in addition, a circle 50 indicating the part where the outer upper collar 50 of the lid is formed is also shown. Further, the positions where the drinking opening 6 and the air hole 7 are arranged in the final product are also shown as indications.

[0019] Figure 6 schematically shows an example of a female mold used for manufacturing the lid 5 according to the present invention. As shown, this mold includes a first protruding portion 94 that conforms to the desired shape (e.g., elliptical) of the drinking opening 6, and a second protruding portion 33 that conforms to the shape (e.g., circular) of the air hole 7. Furthermore, it can be seen that the diameter of the outer peripheral portion 92 of the mold has a diameter corresponding to the line of the circle 50 of the pre-cut raw material 8.

[0020] As shown in Figure 5, when manufacturing the lid 5, pre-cut blanks 8, i.e., multiple hexagonal sections, are cut from a wide raw material sheet, and each is used to manufacture one lid 5. It can be seen that by adopting a hexagonal shape, the yield of the raw material sheet can be greatly improved compared to using circular raw materials. This is because, as shown in the figure, multiple adjacent raw materials 8' can be punched out without gaps, resulting in no waste. It is clear that a similar principle can be applied to rectangular pre-cut blanks as well.

[0021] After cutting out the sheet-like raw material 8, it is lowered into the mold 9, whereupon the protrusions 94 and 93 penetrate the raw material, pushing the fibers laterally into adjacent areas. Further lowering causes the edges 81 and 82 of the raw material 8 to bend upward and align with the inner wall 92 of the mold 9. When the stamp is then pressed into the mold 9 from above, the uppermost edge 82 is first pushed / compressed into the lower part 81 of the color area, thereby pushing the corner 82 of the raw material 8 into the cylindrically formed lower part 81 and integrating it with the portion forming the outer color wall 50. As a result, the amount of fiber in the integrated portion of the corner 82 increases, forming the reinforcing member 3. Similarly, the fibers pushed aside by the protrusions 94 and 93 concentrate around these openings 6 and 7, forming the reinforcing member 3. As shown in Figure 4, by using a stamp (not shown) that maintains a uniform thickness for the lid, the density of the reinforcing member 3 becomes higher than that of other parts of the support 2 of the lid 5. That is, greater strength is obtained through increased density.

[0022] As is understood, the reinforcing member 3 can be formed in various ways. However, in the transverse direction, the amount of fiber in the reinforcing member is always greater than that in the main part of the support 20.

[0023] As will be apparent to those skilled in the art, the above embodiments can be used in combination, and by adjusting the dimensions of the mold, different characteristics can be obtained, thereby realizing a reinforcing member 3 having desired characteristics in different parts of a single product. However, in all cases, it is important that the reinforcing member 3 is integrated with the other parts.

Claims

1. A method for press-forming a pre-formed press-molded textile product, which is formed using a press pad device (9) and a stamping device under high pressure and high temperature, The press pad device (9) has an opening space (91) having a bottom (94) and a wall (92), The stamping device has a fitting shape that forms a gap between products with respect to the press pad device (9), The textile products (1, 5) are manufactured by forming a sheet-like blank (8) made of an integrated fiber network, which is obtained by cutting from a raw material sheet made of an integrated fiber network, within the gap between the products; that is, after press molding, the blank (8) is formed into the textile products (1, 5). The blank (8) is provided with at least one excess portion (82), The at least one excess portion (82) is pushed into the adjacent portion of the blank (8) before or during pressing and integrated into the at least one reinforcing portion (3) of the textile product (1, 5). A press molding method characterized by the following features.

2. A press forming method according to claim 1, After pressing, the reinforcing portion (3) is integrated with the support (20), and the thickness (t1) of the support (20) is smaller than the thickness (t2) of the reinforcing body (30) of the reinforcing portion (3). A press molding method characterized by the following features.

3. A press forming method according to claim 1 or 2, Before pressing, the at least one excess portion (82) is pushed into the adjacent portion of the blank (8) by at least one protruding device (93, 94) located within the press pad device (9), thereby forming at least one opening (6, 7) having reinforcing members (30, 34, 35) at the edges of the openings (6, 7). A press molding method characterized by the following features.

4. A press forming method according to claim 1, During pressing, the corners (82) of the polygonal blank (8) are pushed into the edge region (81) of the textile product (5), thereby pushing the at least one excess portion (82) into the adjacent portion of the blank (8). A press molding method characterized by the following features.

5. A press forming method according to claim 1, The materials include natural fibers and / or recycled fibers such as wood, straw, and bagasse, or combinations thereof. A press molding method characterized by the following features.

6. A press forming method according to claim 1, The molding temperature is 150 to 250°C, and the pressure applied to the bottom (11) is at least 200 bar. A press molding method characterized by the following features.

7. A press forming method according to claim 1, The sheet-like blank (8) is configured such that the amount of moisture in it does not exceed the amount of fiber, preferably the amount of moisture in the material does not exceed 20% of the fiber weight. A press molding method characterized by the following features.

8. A press forming method according to claim 1, The pre-cut blank (8) is cut from a sheet having a uniform fiber distribution in each cross-sectional area used and a substantially constant thickness, so that all parts used have substantially the same density. A press molding method characterized by the following features.

9. A pre-formed press-molded fiber product obtained from an integrated fiber network by the method described in any one of claims 1 to 8, The device comprises a support (20) and at least one reinforcing member (3) integrated with the support (20), The reinforcing member (3) has a reinforcing body (30) that contains more fibers than the main body (20) of the support (2), The pre-formed press-molded textile product (5) has openings (4, 6, 7, 35) surrounded by the reinforcing members (3). A pre-formed, press-molded textile product characterized by the following features.

10. A pre-formed press-molded fiber product according to claim 9, The reinforcing body (30) forms a semi-closed opening (35) having an edge for supporting an object. A pre-formed, press-molded textile product characterized by the following features.

11. A pre-formed press-molded textile product according to claim 9 or 10, The thickness (t2) of the reinforcing member (30) is greater than the thickness (t1) of the main body (20). A pre-formed, press-molded textile product characterized by the following features.

12. A pre-formed press-molded fiber product for supporting an object according to claim 11, The aforementioned thickness is in the range of 1.1 × t1 < t2 < 3 × t1. A pre-formed, press-molded fiber product for supporting objects, characterized by the features described herein.

13. A pre-formed press-molded fiber product for supporting an object according to any one of claims 9 to 12, The width (W) of the reinforcing body (30) is greater than the thickness (t2) of the reinforcing body (30). A pre-formed, press-molded fiber product for supporting objects, characterized by the features described herein.

14. A pre-formed press-molded fiber product for supporting an object according to claim 13, The range of the width (W) of the reinforcing body (30) is 1.1 × t2 < W < 3 × t2. A pre-formed, press-molded fiber product for supporting objects, characterized by the features described herein.

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