COVERING LAYERS FOR ELASTIC LAMINATE THAT COMPRISE A SEPARATE SURFACE COATING

Abstract

The invention relates to a method for producing a covering layer for elastic laminate comprising a) impregnating a carrier fabric, b) applying a surface coating comprising a crosslinker and a prepolymer that can be crosslinked via reactive end groups, c) crosslinking the crosslinkable prepolymer, and d) drying the elastic laminate covering layer. The papers obtainable in this manner are suitable for producing a laminate that, with the elastic outer face thereof, has a pleasant and appealing feel underfoot and good haptics.

Claims

1. A process for the production of an elastic laminate cover layer comprising the steps of: a. impregnating a carrier fabric with a first resin mixture, b. applying one-sidedly a second resin mixture as a surface coating comprising a crosslinker and a prepolymer that is crosslinkable via reactive end groups, c. crosslinking of the prepolymer, and d. drying the resulting elastic laminate cover layer.

2. The process according to claim 1, whereby the reactive end groups are selected from the group consisting of amino, hydroxy, carboxy/carboxylate and mercapto functions.

3. The process according to claim 1 further comprising an intermediate drying of the impregnated carrier fabric before the application of the second resin mixture.

4. The process according to claim 1 wherein the carrier fabric is an overlay paper of alpha-cellulose.

5. The process according to claim 1 wherein the carrier fabric is a printed, coloured or through-coloured decorative paper.

6. The process according to claim 1 wherein the first and the second resin mixtures are aqueous or organic dispersions and optionally comprise at least one further excipient.

7. The process according to claim 1 wherein at least one of the first and the second resin mixtures contains hard particles of corundum, silicon carbide or titanium nitride with an average particle size of 0.5 to 150 μm.

8. The process according to claim 3 wherein, after the application of at least one of the first and the second resin mixture and before the respective drying, hard particles of corundum, silicon carbide or titanium nitride with an average particle size of 0.5 to 150 μm are scattered on the respective resin mixture.

9. The process according to claim 1 wherein the first resin mixture comprises at least one of a melamine resin, a polyurethane, a polyacrylate and a polyurethane/polyacrylate-hybrid-polymer, and, optionally, a crosslinker.

10. The process according to claim 9, whereby the polyurethane and the polyacrylate are crosslinkable via reactive end groups.

11. The process according to claim 1 wherein the prepolymer is a polyurethane, a polyacrylate or a polyurethane/polyacrylate-hybrid-polymer.

12. The process according to claim 10 wherein the polyurethane is crosslinkable via NH2-groups and the polyacrylate is crosslinkable via OH-groups.

13. The process according to claim 1 wherein whereby the second resin mixture is free of prepolymers that have a tendency towards yellowing with UV radiation.

14. The process according to claim 1 wherein the first and the second resin mixtures are free of antioxidants, plasticizers and UV-stabilizers.

15. The process according to claim 1 wherein the crosslinker is an isocyanate, an epoxide or an aziridine.

16. An elastic laminate cover layer made by the process of claim 1.

17. The process of claim 1 for the production of a layered structure, whereby the side of the laminate cover layer on which the surface coating is applied faces an outside of the layered structure.

18. (canceled)

19. The process according to claim 11 wherein the polyurethane is crosslinkable via NH2-groups and the polyacrylate is crosslinkable via OH-groups.

Description

COMPARATIVE EXAMPLE 1

[0028] Impregnation with an aqueous dispersion comprising a non-functional polyurethane (without reactive end groups) and a non-functional polyacrylate (also without reactive end groups) with the addition of a crosslinker in order to form a separate polyurea network and to bring about a polyurethane-polyacrylate-polyurea “interpenetrating network”.

Resin Mixture for the Core Impregnation:

[0029]

TABLE-US-00001 PUD: Bayer Impranil DLC-F 750 g Polyacrylate: Helios Domemul 7960 250 g Water 100 g Crosslinker polyisocyanate Dancure 101 100 g Wetting/separating agent Deurowood MA7  10 g

Dip Impregnation

[0030] Wet impregnation 1: smooth up/smooth down, 20 seconds pre-drying [0031] Wet impregnation 2: 600 μm/700 μm (distance between the grooves of the squeegee), 90 seconds drying

Result:

[0032]

TABLE-US-00002 Final weight:  128 g/m.sup.2 Residual moisture: 6.5% Resin applied: 97.7 g/m.sup.2

[0033] Strong sticking to the press plate, visible and flat transparency disruptions

COMPARATIVE EXAMPLE 2

[0034] Impregnation with an aqueous dispersion comprising a polyurethane/polyacrylate-hybrid-polymer, whereby the polyurethane in the polyurethane/polyacrylate-hybrid-polymer is crosslinkable via NH.sub.2-groups; use of a corundum-filled overlay with a basis weight of 25 g/m.sup.2 and with 3 g/m.sup.2 of corundum

Resin Mixture Core Impregnation

[0035]

TABLE-US-00003 PUR/polyacrylate-hybrid: Ecronova ET 2012 1000 g Water  200 g Wetting/separating agent Deurowood MA7  10 g

Pre-Impregnation

[0036] Wet impregnation 1: 800 μm/800 μm, 20 seconds pre-drying [0037] Wet impregnation 2: 800 μm/800 μm, 145 seconds drying

Result:

[0038]

TABLE-US-00004 Final weight: 125 g/m.sup.2 Residual moisture: 4.3% Resin applied: 95.5 g/m.sup.2,

[0039] Complete sticking to the press plate, mechanically not separable anymore from the press plate, press plate destroyed and an absolutely unusable product

EXAMPLE 1

[0040] Impregnation with an aqueous dispersion comprising a polyurethane prepolymer that is crosslinkable via NH.sub.2-groups; surface coating with an aqueous dispersion comprising a polyacrylate that is linkable via OH-groups and additionally self-linkable

Resin Mixture for the Core Impregnation:

[0041]

TABLE-US-00005 PUD Ecronova ET 4075 1000 g  Water 150 g  Crosslinker Bayhydur XP 2655 20 g Wetting/separating agent Deurowood MA7 10 g

Dip Impregnation

[0042] Wet impregnation 1: 500 μm/500 μm, 20 seconds pre-drying [0043] Wet impregnation 2: 500 μm/500 μm, 90 seconds drying

Resin Mixture for the Surface Coating

[0044]

TABLE-US-00006 Polyacrylate Ecronova Ecrylic RA646H 1000 g  Water 200 g Crosslinker Bayhydur XP 2655 100 g Wetting/separating agent Deurowood MA7  10 g

Surface Coating

[0045] 400 μm, 110 seconds drying

Result:

[0046] Final weight: 115 g/m.sup.2 [0047] Residual moisture: 2.6% [0048] Resin applied: 90 g/m.sup.2, core 58 g/m.sup.2, surface 32 g/m.sup.2 [0049] No sticking to the plate, transparent

EXAMPLE 2

[0050] Impregnation with an aqueous dispersion comprising a polyurethane pre-polymer that is crosslinkable via NH.sub.2-groups; surface coating with an aqueous dispersion comprising a polyacrylate that is linkable via OH-groups and additionally self-linkable; use of a corundum-filled overlay with a basis weight of 25 g/m.sup.2 and with 3 g/m.sup.2 of corundum

Resin Mixture Core Impregnation

[0051]

TABLE-US-00007 PUD: Ecronova ET 4075 1000 g  Water 150 g  Crosslinker Bayhydur XP 2655 20 g Wetting/separating agent Deurowood MA7 10 g

Dip Impregnation

[0052] Wet impregnation 1: 800 μm/800 μm, 20 seconds pre-drying [0053] Wet impregnation 2: 800 μm/800 μm, 110 seconds drying

Resin Mixture Surface Coating

[0054]

TABLE-US-00008 Polyacrylate Ecronova Ecrylic RA646H 1000 g  Water 200 g Crosslinker Bayhydur XP 2655 100 g Microcorundum WCA5 100 g Wetting/separating agent Deurowood MA7  10 g

Surface Coating

[0055] 600 μm, 90 seconds drying

Result:

[0056] Final weight: 123.4 g/m.sup.2 [0057] Residual moisture: 2.3% [0058] Resin applied: 96 g/m.sup.2, core 56 g/m.sup.2, surface 40 g/m.sup.2 [0059] No sticking to the plate, transparent [0060] Abrasion resistance 1700 revolutions according to DIN 13329 [0061] Resistance to micro-scratches MSR-A2 (reduction in the degree of gloss) [0062] MSR-B3 (micro-scratching)

EXAMPLE 3

[0063] Impregnation with an aqueous dispersion comprising a polyurethane/polyacrylate-hybrid-polymer, whereby the polyurethane in the polyurethane/polyacrylate-hybrid-polymer is crosslinkable by NH.sub.2-groups; surface coating with an aqueous dispersion comprising a polyacrylate and a polyurethane/polyacrylate-hybrid-polymer, whereby the polyacrylate is cross-linkable via OH-groups and self-linkable, and the polyurethane in the polyurethane/polyacrylate-hybrid-polymer is crosslinkable via NH.sub.2-groups; use of a corundum-filled overlay with a basis weight of 25 g/m.sup.2 and with 3 g/m.sup.2 of corundum

Resin Mixture Core Impregnation

[0064]

TABLE-US-00009 PUR/polyacrylate-hybrid: Ecronova ET 2012 1000 g  Water 200 g Wetting/separating agent Deurowood MA7  10 g

Dip Impregnation

[0065] Wet impregnation 1: 800 μm/800 μm, 20 seconds pre-drying [0066] Wet impregnation 2: 800 μm/800 μm, 145 seconds drying

Resin Mixture Surface Coating

[0067]

TABLE-US-00010 Polyacrylate Ecronova Ecrylic RA646H 900 g PUR-polyacrylate-hybrid; Ecronova ET 2012 100 g Crosslinker Bayhydur XP 2655 100 g Microcorundum WCA5 100 g Wetting/separating agent Deurowood MA7  10 g

Surface Coating

[0068] 400 μm, 100 seconds drying

Result:

[0069] Final weight: 155 g/m.sup.2 [0070] Residual moisture: 3.3% [0071] Resin applied: 125 g/m.sup.2, core 95 g/m.sup.2, surface 30 g/m.sup.2 [0072] No sticking to the plate, transparent [0073] Abrasion resistance 1350 revolutions according to DIN 13329 [0074] Resistance to micro-scratches MSR-A3 (reduction in the degree of gloss) [0075] MSR-B3 (micro-scratching)

EXAMPLE 4

[0076] Impregnation with an aqueous dispersion comprising a polyurethane/polyacrylate-hybrid-polymer, whereby the polyurethane in the polyurethane/polyacrylate-hybrid-polymer is crosslinkable via NH.sub.2-groups; surface coating with an aqueous dispersion comprising a polyacrylate and a polyurethane/polyacrylate-hybrid-polymer, whereby the polyacrylate is crosslinkable via OH-groups and self-linkable, and the polyurethane in the polyurethane/polyacrylate-hybrid-polymer is cross-linkable via NH.sub.2-groups; use of a corundum-filled overlay with a basis weight of 25 g/m.sup.2 and with 3 g/m.sup.2 of corundum

Resin Mixture Core Impregnation

[0077]

TABLE-US-00011 PUR/acrylate-hybrid: Ecronova ET 2012 1000 g Water  200 g Wetting/separating agent Deurowood MA7  10 g [0078] Wet impregnation 1: 800 μm/800 μm, 20 seconds pre-drying [0079] Wet impregnation 2: 800 μm/800 μm, 60 seconds intermediate drying [0080] Wet impregnation 3: 800 μm/800 μm, 150 seconds intermediate drying

Resin Mixture Surface Coating

[0081]

TABLE-US-00012 Polyacrylate Ecronova Ecrylic RA646H 800 g PUD: Ecronova ET 2012-1036-2 200 g Crosslinker Bayhydur XP 2655 100 g Microcorundum WCA5 100 g Wetting/separating agent Deurowood MA7  10 g

Surface Coating

[0082] one-sided 500 μm, 130 seconds drying

Result:

[0083] Final weight: 142 g/m.sup.2 [0084] Residual moisture: 2.5% [0085] Resin applied: 123 g/m.sup.2, core 92 g/m.sup.2, surface 31 g/m.sup.2 [0086] No sticking to the plate, transparent [0087] Abrasion resistance 1400 revolutions according to DIN 13329 [0088] Resistance to micro-scratching MSR-A2 (reduction of the degree of gloss) [0089] MSR-B3 (micro-scratching)

EXAMPLE 5

[0090] Impregnation with an aqueous dispersion comprising a non-functional polyurethane (without reactive end groups); surface coating with an aqueous dispersion comprising a polyacrylate that is linkable over OH-groups and additionally self-linkable; use of a corundum-filled overlay with a basis weight of 25 g/m.sup.2 and with 3 g/m.sup.2 of corundum

Resin Mixture for the Core Impregnation:

[0091]

TABLE-US-00013 PUD: Imperial DLC-F 1000 g Water  100 g Wetting/separating agent Deurowood MA7  10 g

Dip Impregnation

[0092] Wet impregnation 1: 500 μm/500 μm, 20 seconds pre-drying [0093] Wet impregnation 2: 500 μm/500 μm, 110 seconds drying

Resin Mixture for the Surface Coating

[0094]

TABLE-US-00014 Polyacrylate Ecronova Ecrylic RA646H 1000 g  Water 50 g Crosslinker Bayhydur XP 2655 100 g  Wetting/separating agent Deurowood MA7 10 g Microcorundum WCA5 100 g 

Surface Coating

[0095] 600 μm, 110 seconds drying

Result:

[0096] Final weight: 134 g/m.sup.2 [0097] Residual moisture: 2.8% [0098] Resin applied: 130 g/m.sup.2, core 79 g/m.sup.2, surface 26 g/m.sup.2 [0099] No sticking to the plate, transparent [0100] Abrasion resistance 750 revolutions according to DIN 13329 [0101] Resistance to micro-scratches MSR-A3 (decrease in the degree of gloss) [0102] MSR-B3 (micro-scratching)

EXAMPLE 6

[0103] Impregnation with an aqueous dispersion comprising a non-functional polyurethane (without reactive end groups); surface coating with an aqueous dispersion comprising a polyacrylate that is linkable via OH-groups and additionally self-linkable and a non-functional polyurethane (without reactive end groups); use of a corundum-filled overlay with a basis weight of 25 g/m.sup.2 and with 3 g/m.sup.2 of corundum

Resin Mixture for the Core Impregnation:

[0104]

TABLE-US-00015 PUD: Impranil DLC-F 1000 g Water  150 g Wetting/separating agent Deurowood MA7  10 g

Dip Impregnation

[0105] Wet impregnation 1: 800 μm/800 μm, 20 seconds pre-drying [0106] Wet impregnation 2: 800 μm/800 μm, 110 seconds drying

Resin Mixture for the Surface Coating

[0107]

TABLE-US-00016 Polyacrylate: Ecronova Ecrylic RA646H 900 g PUD: Impranil DLC-F 100 g Water  50 g Crosslinker Bayhydur XP 2655 100 g Wetting/separating agent Deurowood MA 7  10 g Microcorundum WCA5 100 g

Surface Coating

[0108] 400 μm, 90 seconds drying

Result:

[0109] Final weight: 134 g/m.sup.2 [0110] Residual moisture: 2.0% [0111] Resin applied: 131 g/m.sup.2, core 80 g/m.sup.2, surface 26 g/m.sup.2 [0112] No sticking to the plate, transparent [0113] Abrasion test 780 revolutions according to DIN EN 13329 [0114] Micro-scratching MSR-A2 (decrease in the degree of gloss) [0115] MSR-B3 (micro-scratching)