Method for producing shaped products from multi-layer paper, shaped product made of paper, and device for the production thereof

Abstract

A method for producing shaped products from multi-layer paper dispenses with subsequent drying steps and still allows entirely compostable shaped products to be produced that, in terms of their shape, are not limited to flat angles between flat regions. A corresponding shaped product made of paper and to a device for carrying out the method are disclosed.

Claims

1.-15. (canceled)

16. A method for producing shaped products from multi-layer paper, comprising: i) feeding a plurality of paper layers arranged one above another between a positive mold and a complementary negative mold of a pressing tool with pressing surfaces, each of the paper layers having a plurality of free fiber ends on its surface; ii) aligning the free fiber ends transversely to top and bottom sides of the paper layers by suctioning off or feeding a gas or gas mixture, wherein a flow direction of the gas or gas mixture corresponds to a desired alignment; and iii) pressing the paper layers to form a shaped product corresponding to the positive mold and the complementary negative mold by the pressing tool.

17. The method according to claim 16, wherein at least one pressing surface is gas-permeable or perforated at least in some regions and the suctioning off or feeding according to step ii) takes place through at least one pressing surface.

18. The method according to claim 16, wherein the multi-layer paper is a creped, cellulose-containing tissue paper, which is stretchable by 20% or more at least in partial regions.

19. The method according to claim 16, wherein the suctioning off of the gas or gas mixture in step ii) creates a negative pressure relative to an ambient pressure between the positive mold and the complementary negative mold, at least for a short time.

20. The method according to claim 16, wherein the paper layers have a solvent or solvent mixture at least in step ii).

21. The method according to claim 20, wherein the solvent or solvent mixture evaporates at an accelerated rate as a result of the suctioning off or feeding of the gas or gas mixture in step ii).

22. The method according to claim 20, wherein a content of the solvent or solvent mixture in steps ii) and iii) is reduced to less than 5% of an initial content or, if the solvent is water, to a moisture content of the shaped product which is less than or equal to a moisture equilibrium between the shaped product and ambient air at 20 C., 50% relative humidity and 1000 hPa ambient air pressure.

23. The method according to claim 20, wherein at least two of the paper layers are spaced apart from one another during the feeding according to step i).

24. The method according to claim 23, wherein the solvent or solvent mixture is nebulized, evaporated, or nebulized and evaporated between the paper layers spaced apart from one another during the feeding of the paper layers according to step i).

25. The method according to claim 16, wherein a pressure during pressing according to step iii) is at least 100 kg/cm2.

26. The method according to claim 16, wherein a temperature of the pressing tool in step iii) is 100 C. to 350 C.

27. The method according to claim 16, wherein a composition of the multi-layer paper is free of elastomer additives and the shaped product is completely compostable.

28. A shaped product (11) produced from multi-layer paper, wherein the shaped product (11) is completely compostable, and wherein the shaped product (11) comprises directly adjoining flat regions (12, 13) which enclose an angle of more than 90 but less than 150, and wherein paper layers of the shaped product (11) have a stretchability of 20% or more, at least in some regions, solely due to creping.

29. A device (1) for producing shaped products (8, 10) from multi-layer paper with a roller arrangement (2) for feeding the multi-layer paper to a pressing tool (7) with a positive mold (5) and a complementary negative mold (6) which exhibit pressing surfaces (5a, 6a) respectively, wherein the pressing tool (7) is heatable to 100 C. to 350 C. and at least one of the pressing surfaces (5a, 6a) is gas-permeable or perforated at least in some regions and is connected via a hose to a compressor or a vacuum pump for suctioning in or feeding a gas or gas mixture through the pressing surface (5a, 6a).

30. The device (1) according to claim 29, wherein an outlet (4) for a solvent or solvent mixture is arranged upstream from the pressing tool (7), wherein the outlet (4) is designed for nebulizing or evaporating the solvent or solvent mixture, wherein a transport device for individual paper layers (3) is configured so that the outlet (4) is positionable between the individual paper layers (3).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0020] FIG. 1 shows a device for producing shaped products from multi-layer paper.

[0021] FIG. 2 shows an example of a shaped product produced from multi-layer paper.

DETAILED DESCRIPTION

[0022] FIG. 1 shows a sketch of the device for producing shaped products from multi-layer paper. The roller arrangement is indicated, which is not necessarily arranged to the side of the pressing tool (7), as shown, but can also be arranged above this (7), for example, in order to utilize the force of gravity when feeding the paper. The individual paper layers (3) can be seen, which are shown here spaced apart from one another in a simple manner by means of the outlet (4) for the solvent or solvent mixture. They can also be spaced apart from one another by means of an additional divider (not shown) positioned upstream from the outlet (4). The multi-layer paper fed over the outlet is guided to the pressing tool (7), whose positive mold (5) engages with pressure in the complementary negative mold (6) and thereby causes the forming of the fed paper into the desired, here highly schematized, shaped product (8), which is separated as an individual part by a cut along the cutting edge (9), as outlined by the previously formed shaped product (10). The pressing surfaces (5a, 6a) have perforations (not shown) through which a gas or gas mixture, in this case ambient air, is suctioned off, even during the pressing process. This creates a negative pressure relative to the ambient pressure, at least for a short time. The hoses leading from the perforations to a vacuum pump (not shown) run advantageously within a sketched cover of the pressing tool. For the sake of simplicity, the feed for the solvent or solvent mixture intended for wetting the paper layers is also not shown.

[0023] FIG. 2 shows an example of a somewhat more complicated shaped product, which was produced here from multi-layer paper by means of the method described above and shows two directly adjoining flat regions (12, 13) which enclose an angle of slightly more than 90 but less than 150 at the end face of the shaped product (11), which in the case of production from multi-layer paper, in contrast to production by the fiber casting method, is only possible without the addition of elastomers if the paper used has a stretchability of 20% or more, in this case more than 50%, at least in some regions, due to creping.

LEGEND

[0024] 1 Device for producing shaped products from multi-layer paper [0025] 2 Roller arrangement [0026] 3 Paper layers [0027] 4 Outlet [0028] 5 Positive mold [0029] 5a Pressing surface of the positive mold [0030] 6 Negative mold [0031] 6a Pressing surface of the negative mold [0032] 7 Pressing tool [0033] 8 Shaped product (still connected) [0034] 9 Cutting edge [0035] 10 Shaped product (separated) [0036] 11 Shaped product [0037] 12 First flat region [0038] 13 Second flat region