Method for the production of adhesive-coated articles, articles obtainable thereby and their use

Patent metadata

Field	Value
Publication number	US-9321939-B2
Application number	US-201113823335-A
Country	US
Kind code	B2
Filing date	Sep 14, 2011
Priority date	Sep 17, 2010
Publication date	Apr 26, 2016
Grant date	Apr 26, 2016

Abstract

Method for the production of adhesive-coated articles, articles obtainable thereby and their use A method for the production of adhesive-coated articles comprises the steps of: (I) providing a substrate; (II) applying a first polyurethane and/or polyurethane-polyurea polymer onto the substrate, the first polyurethane and/or polyurethane-polyurea polymer being capable of attaining an at least partially crystalline state with a final degree of crystallinity and wherein during and/or after the application the first polyurethane and/or polyurethane-polyurea polymer is present in a non-crystalline state. The method further comprises the steps: (III) applying onto the first polyurethane and/or polyurethane-polyurea polymer of step (II) a composition comprising a mixture of a second polyurethane and/or polyurethane-polyurea polymer and furthermore an acrylate polymer, wherein the application is performed while the degree of crystallinity of the first polyurethane-polyurea polymer is lower than its final degree of crystallinity; and (IV) cooling the article obtained to a temperature below the glass transition temperature of the acrylate polymer.

First claim

The invention claimed is:

1. A method for the production of an adhesive-coated article, comprising the steps of:
(I) providing a substrate;
(II) applying a first polyurethane and/or polyurethane-polyurea polymer onto the substrate,
the first polyurethane and/or polyurethane-polyurea polymer being capable of attaining an at least partially crystalline state with a final degree of crystallinity,
wherein during and/or after the application the first polyurethane and/or polyurethane-polyurea polymer is present in a non-crystalline state;
wherein the first polyurethane and/or polyurethane-polymer has a melting temperature from ≧42° C. to ≦80° C., a glass transition temperature from ≧−100° C. to ≦−10° C. and a molecular weight M w from ≧20000 g/mol to ≦80000 g/mol, the glass transition temperature being determined by differential scanning calorimetry according to DIN 65467 at a heating rate of 20 K/min,

wherein the method further comprises the steps:
(III) applying onto the first polyurethane and/or polyurethane-polyurea polymer of step (II) a composition comprising a mixture of a second polyurethane and/or polyurethane-polyurea polymer and furthermore an acrylate polymer,
wherein the application is performed while the degree of crystallinity of the first polyurethane-polyurea polymer is lower than its final degree of crystallinity,
wherein the second polyurethane and/or polyurethane-polyurea polymer has a glass transition temperature from ≧−50° C. to ≦10° C. and the acrylate polymer has a glass transition temperature of ≧30° C., the glass transition temperatures being determined by differential scanning calorimetry according to DIN 65467 at a heating rate of 20 K/min.; and

(IV) cooling the article obtained to a temperature below the glass transition temperature of the acrylate polymer.

2. The method according to claim 1 , wherein the composition in step (III) is applied via intaglio printing.

3. The method according to claim 1 , wherein step (III) is performed ≧0.1 seconds to ≦60 seconds after the end of step (II).

4. The method according to claim 1 , wherein in step (IV) the obtained article is cooled to a temperature below the glass transition temperature of the acrylate polymer via a chill roll.

5. The method according to claim 1 , wherein the method is conducted as a roll-to-roll process.

6. The method according to claim 1 , wherein the composition in step (III) has a thickness of ≧1 μm to ≦50 μm after drying.

7. The method according to claim 1 , wherein the first polyurethane and/or polyurethane-polyurea polymer in step (II) is a latent reactive adhesive and furthermore the second polyurethane and/or polyurethane-polyurea polymer and/or the acrylate polymer in step (III) comprise free isocyanate reactive groups.

8. The method according to claim 1 , wherein the first polyurethane and/or polyurethane-polyurea polymer in step (II) is obtained by the reaction of:
(A) at least one diol and/or polyol component,
(B) at least one di- and/or polyisocyanate component,
(C) at least one component having sulphonate and/or carboxylate groups,
(D) mono-, di- and/or tri-amino-functional and/or hydroxyamino-functional compounds, as appropriate, and
(E) other isocyanate-reactive compounds, as appropriate.

9. The method according to claim 1 , wherein the second polyurethane and/or polyurethane-polyurea polymer in step (III) is obtained by the reaction of:
(A) at least one diol and/or polyol component,
(B) at least one di- and/or polyisocyanate component,
(C) at least one component having sulphonate and/or carboxylate groups,
(D) mono-, di- and/or tri-amino-functional and/or hydroxyamino-functional compounds, as appropriate, and
(E) other isocyanate-reactive compounds, as appropriate.

10. The method according to claim 1 , wherein the acrylate polymer in step (III) is obtained by the reaction of:
(a) ≧40% to ≦70% by weight of styrene and/or other vinyl aromatic compounds,
(b) ≧4% to ≦40% by weight of an acrylic ester,
(c) ≧2% to ≦5% by weight of an acid-functional, olefinically unsaturated monomer and
(d) ≧10% to ≦40% by weight of a methacrylic ester,
wherein the total weight proportions of the components a) to d) amount to ≦100% by weight.

11. An article of manufacture, obtained by the method according to claim 1 , comprising:
a substrate;
a first layer on top of to the substrate,
the first layer comprising a first polyurethane and/or polyurethane-polyurea polymer which has a melting temperature from ≧42° C. to ≦80° C., a glass transition temperature from ≧−100° C. to ≦−10° C. and a molecular weight M w from ≧20000 g/mol to ≦80000 g/mol, and

a second layer on top of to the first layer,
the second layer comprising a second polyurethane and/or polyurethane-polyurea polymer with a glass transition temperature from ≧−50° C. to ≦10° C. and
further comprising an acrylate polymer which has a glass transition temperature of ≧30° C.,

all glass transition temperatures being determined by differential scanning calorimetry according to DIN 65467 at a heating rate of 20 K/min.

12. The article of manufacture according to claim 11 , wherein the article does not comprise a release paper or a release film.

13. A method for coating of an object utilizing the article according to claim 11 .

Assignees

• Büchner Jörg
• Kraus Harald
• Nazaran Pantea
• Wintermantel Matthias
• Covestro Deutschland Ag

Inventors

• Büchner Jörg
• Kraus Harald
• Nazaran Pantea
• Wintermantel Matthias

Classifications

• C08G18/722

  Combination of two or more aliphatic and/or cycloaliphatic polyisocyanates · CPC title

• C08G2170/80

  Compositions for aqueous adhesives · CPC title

• C08G18/4238

  derived from dicarboxylic acids and dialcohols · CPC title

• C08G18/10

  Prepolymer processes involving reaction of isocyanates or isothiocyanates with compounds having active hydrogen in a first reaction step · CPC title

• C08L75/04

  Polyurethanes · CPC title