WO2002094555A1

WO2002094555A1 - Laminate, method for the production thereof and garment containing the laminate

Info

Publication number: WO2002094555A1
Application number: PCT/EP2002/004551
Authority: WO
Inventors: Christian Peter Norhausen; Michael Diamantoglou
Original assignee: Membrana Gmbh
Priority date: 2001-05-22
Filing date: 2002-04-25
Publication date: 2002-11-28

Abstract

A laminate comprising at least one cross-linked cellulose layer, having a pore forming material, and a waterproof functional layer, permeable to water vapour, is provided. Said laminate exhibits, after washing and drying, substantially reduced or no more observable wrinkling or delamination between the cellulose layer and the functional layer.

Description

Laminate, process for its manufacture and the laminate containing it

clothing

Description:

The present invention relates to a laminate, a process for its production and articles of clothing containing the laminate.

US 5743775 describes a laminate for the retention of organic vapors, aerosols and biological agents. The laminate is permeable to water vapor and comprises at least three layers, at least one layer being a cellulosic barrier layer on which a water vapor permeable but waterproof layer, i.e. a breathable layer that is laminated. A disadvantage of this laminate is that when the laminate is washed under normal household conditions and then dried, wrinkling and partial delamination of the cellulosic layer from the breathable layer or even tearing of the cellulosic layer occurs.

Therefore, the object of the present invention is to provide a laminate and method for its production, whereby the disadvantages mentioned are at least significantly reduced.

This object is achieved by a laminate at least comprising a crosslinked cellulosic layer which contains a pore former and a waterproof, water vapor-permeable functional layer. Surprisingly, it was found that when the laminate according to the invention is washed and dried, wrinkling or delamination of the cellulosic layer from the breathable layer or tearing of the cellulosic layer is at least significantly reduced or even no longer observed. The term washing is understood to mean wet treatment with water, for example normal household washing at 30 ° C., 60 ° C. or 95 ° C. or at another temperature that can be set in household washing machines.

Suitable pore formers, which are contained in the cellulosic layer of the laminate according to the invention, are all pore formers known for cellulosic layers, such as e.g. Glycerin or polyethylene glycol, where the substances just mentioned also have a plasticizing function.

The cellulosic layer of the laminate according to the invention is preferably laminated on both sides with a functional layer.

In a further preferred embodiment, the functional layer of the laminate according to the invention is laminated with a textile fabric, e.g. on the side facing away from the cellulosic layer. The textile fabric is e.g. from a lining material made of the fibers known for lining materials, such as polyester fibers.

In a further preferred embodiment, the cellulosic layer of the laminate of the invention is a cellulose film, for example a commercially available from Membrana GmbH under the name ^® Cuprophan cellulose membrane microns with a thickness of, for example, 80th

The laminate according to the invention contains a crosslinked cellulosic layer, ie a layer in which cellulosic polymer chains are connected to one another. In principle, it is irrelevant in which way the named connection is established. For example, the laminate according to the invention can be cellulosic chains contain, which are connected directly, ie by condensation of functional groups in neighboring cellulosic chains. Preferred according to the invention because it is easy to implement, however, is a laminate whose crosslinked cellulosic layer contains a crosslinking agent which covalently connects cellulose chains in the cellulosic layer by means of at least two functional groups, the functional groups being particularly preferably from the group of aldehydes, ketones, Urea, epoxies, alcohols or isocyanates are selected.

In a preferred embodiment, the laminate according to the invention contains a catalyst used for crosslinking, such as MgCl ₂ .

The water-vapor-permeable, waterproof functional layer of the laminate according to the invention can in principle be constructed from any material which, via the combination of properties mentioned, i.e. has breathability. However, the functional layer of the laminate according to the invention is preferably a polyether ester, polyether amide or polyurethane, because these polymers are distinguished by a particularly high degree of breathability.

The object is further achieved by a method for producing a laminate as described above, comprising the steps a) swelling a cellulosic layer with a treatment agent which contains at least water and a crosslinking agent, b) removing excess treatment agent from the swollen cellulosic layer, c ) Crosslinking the cellulosic layer swollen with the treatment agent and d) laminating the crosslinked cellulosic layer with at least one waterproof, water vapor permeable functional layer.

All the pore formers known for cellulosic layers, such as, for example, are suitable as pore formers which are contained in the cellulosic layer according to the invention Glycerin or polyethylene glycol, where the substances just mentioned also have a plasticizing function.

The swelling of the cellulosic layer in step a) in a treatment agent which contains at least water and a crosslinking agent facilitates the diffusion of the crosslinking agent into the cellulosic layer, the water acting to accelerate the diffusion. In addition, the treatment agent used in step a) may contain pore formers and plasticizers, such as e.g. Glycerin or polyethylene glycol, which counteract the diffusion of the pore formers and plasticizers from the cellulosic layer. The swelling of the cellulosic layer in step a) can in principle be carried out using any method which enables the crosslinking agent to diffuse into the cellulosic layer, e.g. by immersing the cellulose layer in the treatment agent or by spraying the cellulose layer with the treatment agent or by passing the cellulose layer over a roller on which a film of the treatment agent is located.

In a preferred embodiment of the inventive method, for example, is used as the cellulosic film, a cellulose film, a micron available from Membrana GmbH under the name ^® Cuprophan cellulose membrane with a thickness of, for example, 80th

In a further preferred embodiment of the process according to the invention, a molecule is preferably selected as the crosslinker which has at least two functional groups which can crosslink cellulosic chains or cellulose chains, functional groups consisting of the group of epoxides, alcohols, aldehydes, ketones, ureas or Isocyanates are selected, are particularly preferred, and the latter are particularly preferably used in blocked form, because in this form they survive the swelling carried out in step a) of the process according to the invention in an aqueous treatment agent without damage. Examples of crosslinkers selected from the group of epoxides are bispoxides, such as ethylene glycol diglycidyl ether, which is available under the name DENACOL EX-810 from NAGASE CHEMICALS LTD, or molecules which have epoxy and alcohol groups, such as sorbitol polyglycidyl ether , which is also available under the name DENACOL EX-611 from NAGASE CHEMICALS LTD.

Examples of crosslinkers selected from the group of alcohols are hydroxy-functionalized cyclic urea derivatives such as N-methyloldihydroxyethylene urea, which is available under the name Arkofix NDS from Clariant, or dimethyldihydroxyethylene urea, also under the name Arkofix NZF from Clariant is available.

Examples of crosslinkers selected from the group of isocyanates are, in particular, blocked isocyanates such as the compounds BAYPRET CA 40 175 available from BAYER, a bisulfide-blocked isocyanate or BAYGARD 40 140, which has been marketed since 1999 under the name BAYGARD EDW and a represents oxime-blocked triisocyanate. The BAYGARD crosslinkers have the particular advantage that their use in the process according to the invention leads to laminates in which wrinkling or delamination of the cellulosic layer from the breathable layer or tearing of the cellulosic layer is practically no longer observed.

The BAYPRET and BAYGARD crosslinkers also have the advantage that they can be used as a result of their high reactivity in the process according to the invention without a crosslinking catalyst. In the case of somewhat less active crosslinking agents, such as those of the Arcofix type, a crosslinking catalyst, such as MgCl ₂ , is preferably added to the treatment agent in step a).

The swelling carried out in step a) of the process according to the invention takes place within a few seconds to about 10 minutes at room temperature, that is, rather quickly, so that swelling is preferably carried out in this temperature range.

The crosslinking taking place in step d) of the process according to the invention takes place at a temperature which, depending on the crosslinking agent and catalyst used, leads on the one hand to a sufficiently rapid crosslinking rate but on the other hand does not thermally degrade the cellulosic layer. Crosslinking can thus be carried out in a wide temperature range in the process according to the invention. The crosslinking is preferably carried out at a temperature in the range from room temperature to about 140 ° C.

It goes without saying that, in view of the various crosslinking agents and temperatures that can be used with or without a catalyst, the times in which the crosslinking takes place are in a wide range. The crosslinking is preferably carried out within about 1 minute to about 2 hours.

In step d) of the method according to the invention, the crosslinked cellulosic layer is laminated with a waterproof, water vapor-permeable, ie with a breathable functional layer, a functional layer preferably being selected from a polyether ester, polyether amide or polyurethane, because these polymers are distinguished by a particularly high breathability. The lamination can be done, for example, by gluing the cellulosic layer to the functional layer point by point. Before the lamination, the crosslinked cellulosic layer is dried, if it has not already dried during the crosslinking. Furthermore, the object is achieved by a method for producing a laminate at least comprising a cellulosic layer which contains a pore former, and a waterproof, water vapor-permeable functional layer comprising the steps a) laminating a cellulosic layer which contains a pore former with at least one watertight, water vapor permeable Functional layer, whereby a starting laminate is obtained, b) swelling of the starting laminate with a treatment agent containing water and a crosslinking agent, c) removal of excess treatment agent from the starting laminate and d) crosslinking of the cellulosic layer of the starting laminate.

What has already been said applies to the cellulosic layer, the pore former, the functional layer, the swelling, the treatment agent, the crosslinking agent and the crosslinking, since the essential difference from the previously described method according to the invention is only that a starting laminate consisting of a cellulosic layer and a waterproof, water vapor-permeable, ie a breathable functional layer is used, which preferably consists of a polyether ester, polyether amide or polyurethane for the reasons already mentioned.

Articles of clothing which contain a laminate according to the invention or a laminate produced by one of the methods according to the invention are suitable as water vapor-permeable protection against toxic vapors, aerosols and biological active substances.

Preferred embodiments of the items of clothing according to the invention are work clothing, protective work clothing, military protective clothing, gloves, work shoes, headgear and tracksuits. The evaluation of the tendency of the laminates according to the invention to crease, delaminate or tear during washing and drying is carried out according to the following evaluation, reference being made to a laminate which differs from the laminate according to the invention only in that the cellulosic layer is not treated according to the invention.

+ means a significantly increased resistance of the laminate against wrinkling, delamination or tearing of the cellulosic layer.

++ means hardly any wrinkles, delamination or tearing of the cellulosic layer.

+++ means no wrinkling, delamination and tearing of the cellulosic layer.

The invention is illustrated by the following examples.

example 1

A Cuprophan membrane with a thickness of 80 μm from Membrana GmbH is swollen in a treatment agent which consists of H ₂ O, glycerol, Denacol EX-810 and NaOH with the parts by weight given in Table 1. The membrane is then crosslinked with the values of temperature T and time t likewise given in Table 1.

Table 1: Cross-linking of a Cuprophan membrane with Denacol EX-810

Laminates with a breathable functional layer produced with the treated cellulose membranes from Table 1 show, after washing and drying, a significantly increased resistance to wrinkling, delamination or tearing of the Cuprophan membrane in comparison to laminates, which were produced under the same conditions but with an untreated Cuprophan membrane become.

Example 2

A Cuprophan membrane with a thickness of 80 μm from Membrana GmbH is swollen in a treatment agent consisting of H ₂ O, Arcofix NDS and MgCl ₂ with the parts by weight given in Table 2. The membrane is then crosslinked with the values of temperature T and time t likewise given in Table 2.

Table 2: Cross-linking of a Cuprophan membrane with Arcofix NDS

A laminate with a breathable functional layer produced with the treated cellulose membrane of test number 8 from Table 2 shows, after washing and drying, a significantly increased resistance to wrinkling, delamination or tearing of the Cuprophan membrane as a laminate, but under the same conditions but with an untreated Cuprophan Membrane was manufactured. A laminate that was produced with a Cuprophan membrane according to test number 10 from Table 2 shows hardly any tendency to wrinkle, delaminate or tear the Cuprophan membrane. A laminate that was produced with a Cuprophan membrane according to test number 9 from Table 2 shows no wrinkling, delamination or tearing of the Cuprophan membrane.

Example 3

A Cuprophan membrane with a thickness of 80 μm from Membrana GmbH is swollen in a treatment agent consisting of H ₂ 0, Arcofix NZF and MgCl ₂ with the parts by weight given in Table 3. The membrane is then crosslinked with the values of temperature T and time t likewise given in Table 3.

Table 3: Crosslinking of a Cuprophan membrane with Arcofix NZF

Laminates, which are produced with the treated cellulose membranes from Table 3 and with a breathable functional layer, show a significantly increased resistance to wrinkling, delamination or tearing of the Cuprophan membrane after washing and drying in comparison to laminates which, under the same conditions but with a untreated cuprophan membrane.

Example 4

A Cuprophan membrane with a thickness of 80 μm from Membrana GmbH is swollen in a treatment agent consisting of H ₂ 0 and BAYPRET CA 40175 with the parts by weight given in Table 4. The membrane is then crosslinked with the values of temperature T and time t likewise given in Table 4.

Table 4: Crosslinking of a Cuprophan membrane with BAYPRET CA 40175

Laminates made with the treated cellulose membranes of Table 4 and with a breathable functional layer show after washing and Drying significantly increased resistance to wrinkling, delamination or tearing of the Cuprophan membrane compared to laminates, which were produced under the same conditions but with an untreated Cuprophan membrane.

Example 5

A Cuprophan membrane with a thickness of 80 μm from Membrana GmbH is swollen in a treatment agent consisting of H ₂ 0 and BAYGARD CA 40140 with the parts by weight given in Table 5. The membrane is then crosslinked with the values of temperature T and time t likewise given in Table 5.

Table 5: Cross-linking of a Cuprophan membrane with BAYGARD CA 40140

Laminates which are produced with a treated cellulose membrane from Table 5 and with a breathable functional layer do not show any wrinkling, delamination or tearing of the Cuprophan membrane after washing and drying.

Example 6

A Cuprophan membrane with a thickness of 80 μm from Membrana GmbH is swollen in a treatment agent which consists of H ₂ O, polyethylene glycol with an average molecular weight of 4000 (PEG 4000) and BAYGARD EDW with the parts by weight given in Table 6. The membrane is then crosslinked with the values of temperature T and time t likewise given in Table 6.

Table 6: Crosslinking of a Cuprophan membrane with BAYGARD EDW

Laminates with a breathable functional layer and with Cuprophan membrane No. 16 or 17 from Table 6 hardly show any wrinkling, delamination or tearing of the Cuprophan membrane after washing and drying. Laminates which are produced with a breathable functional layer and with Cuprophan membrane No. 18 or 19 from Table 6 do not show any wrinkling, delamination or tearing of the Cuprophan membrane after washing and drying.

Claims

claims:

1. Laminate at least containing a crosslinked cellulosic layer containing a pore former and a waterproof, water vapor permeable functional layer.

2. Laminate according to claim 1, characterized in that the cellulosic layer is laminated on both sides with a functional layer.

3. Laminate according to claim 2, characterized in that the functional layer is connected to a textile fabric.

4. Laminate according to one or more of claims 1 to 3, characterized in that the cellulosic layer is a cellulose membrane.

5. Laminate according to one or more of claims 1 to 5, characterized in that the crosslinked cellulosic layer contains a crosslinking agent which covalently connects cellulose chains in the cellulosic layer by means of at least two functional groups.

6. Laminate according to claim 5, characterized in that the functional groups are selected from the group of epoxides, alcohols, ketones, aldehydes, ureas or isocyanates.

7. Laminate according to claim 5, characterized in that the laminate contains a catalyst used for crosslinking.

8. Laminate according to one or more of claims 1 to 7, characterized in that the functional layer is a polyether ester, polyether amide or polyurethane.

9. A method for producing a laminate according to one of claims 1 to 8, comprising the steps a) swelling a cellulosic layer with a treatment agent which contains at least water and a crosslinker, b) removing excess treatment agent from the swollen cellulosic layer, c) crosslinking the cellulosic layer swollen with the treatment agent and d) laminating the crosslinked cellulosic layer with at least one waterproof, water vapor-permeable functional layer.

10. The method according to claim 9, characterized in that a cellulose membrane is used as the cellulosic layer.

11. The method according to claim 9 or 10, characterized in that a molecule is selected as crosslinker in step a) which has at least two functional groups which can crosslink cellulose chains or cellulose chains.

12. The method according to claim 11, characterized in that the functional groups are selected from the group of epoxides, alcohols, aldehydes, ketones, ureas or isocyanates.

13. The method according to one or more of claims 9 to 12, characterized in that a crosslinking catalyst is added to the treatment agent according to step a).

14. The method according to one or more of claims 9 to 13, characterized in that in step a) the swelling is carried out at room temperature.

15. The method according to one or more of claims 9 to 14, characterized in that in step c) the crosslinking is carried out at a temperature in the range from room temperature to about 140 ° C.

16. The method according to one or more of claims 9 to 15, characterized in that in step c) the crosslinking is carried out within about 1 minute to about 2 hours.

17. The method according to one or more of claims 9 to 16, characterized in that in step d) a functional layer is selected for lamination, which consists of a polyether ester, polyether amide or polyurethane.

18. A method for producing a laminate comprising at least one cellulosic layer containing a pore former and a waterproof, water vapor-permeable functional layer comprising the steps a) laminating a cellulosic layer containing a pore former with at least one waterproof, water vapor permeable functional layer, thereby producing a starting laminate is obtained, b) swelling the starting laminate with a treatment agent which contains water and a crosslinking agent, c) removing excess treatment agent from the starting laminate and d) crosslinking the cellulosic layer of the starting laminate.

19. The method according to claim 18, characterized in that a cellulose membrane is used as the cellulosic layer in step a).

20. The method according to claim 18 or 19, characterized in that in step a) a polyether ester, polyether amide or polyurethane is used as the functional layer.

21. The method according to claim 18 or 19, characterized in that a molecule is selected as the crosslinker in step b) which has at least two functional groups which can crosslink cellulose chains or cellulose chains.

22. The method according to claim 12, characterized in that the functional groups are selected from the group of epoxides, alcohols, aldehydes, ketones, ureas or isocyanates.

23. The method according to one or more of claims 18 to 22, characterized in that a crosslinking catalyst is added to the treatment agent according to step b).

24. The method according to one or more of claims 18 to 23, characterized in that in step b) the swelling is carried out at room temperature.

25. The method according to one or more of claims 18 to 24, characterized in that in step d) the crosslinking is carried out at a temperature in the range from room temperature to about 140 ° C.

26. The method according to one or more of claims 18 to 25, characterized in that in step d) the crosslinking is carried out within about 1 minute to about 2 hours.

27. Clothing, suitable as water vapor permeable protection against toxic vapors, aerosols and biological agents and containing a laminate according to one or more of claims 1 to 8.

28. Clothing, suitable as water vapor permeable protection against toxic vapors, aerosols and biological active substances and containing a laminate produced according to one or more of claims 9 to 17 or 18 to 26.

29. Clothing according to claim 27 or 28, characterized in that the clothing is work clothing, protective work clothing, military protective clothing, gloves, work shoes, headgear and tracksuits.