Polyurethane urea solutions for textile coatings

Patent metadata

Field	Value
Publication number	US-10358575-B2
Application number	US-201515501036-A
Country	US
Kind code	B2
Filing date	Mar 26, 2015
Priority date	Aug 5, 2014
Publication date	Jul 23, 2019
Grant date	Jul 23, 2019

Abstract

The invention relates to a method for coating textiles and/or leather, comprising applying at least one polyurethane urea dissolved in a solvent or solvent mixture, wherein the solvent consists of one or more monohydroxy-functional alcohols, or a solvent mixture consisting of organic solvents, containing >80 wt. % of at least one monohydroxy-functional alcohol in relation to the total mass of the solvent mixture is used, and wherein the polyurethane urea is formed by: a) at least one araliphatic, aliphatic and/or cycloaliphatic diisocyanate; b) at least one polyether polyol having a number average molecular weight Mn≥400 and ≤6000 g/mol and an average hydroxyl functionality of ≥1.5 and ≤4; c) at least one amino-functional compound having at least two isocyanate reactive amino groups; and optionally other components. The invention also relates to a textile or leather coating produced using this method and a dissolved polyurethane urea, and to the use of the polyurethane urea for coating substrates and for producing free films.

First claim

The invention claimed is:

1. A process for coating one of textiles and leather, comprising applying to the one of textiles and leather at least one polyurethane urea formed from
a) at least one of an araliphatic, an aliphatic and a cycloaliphatic diisocyanate,
b) at least one polyether polyol having a number-average molecular weight M n of ≥400 and ≤6000 g/mol, determined by means of gel permeation chromatography (GPC) in tetrahydrofuran (THF) at 23° C., and a mean hydroxyl functionality of ≥1.5 and ≤4,
c) at least one amino-functional compound having at least two isocyanate-reactive amino groups,
d) optionally, at least one alcohol having at least two hydroxyl groups and a molar mass of ≥60 and ≤399 g/mol,
e) optionally, at least one compound having a group reactive toward isocyanate groups,
f) optionally, ≤20% by weight, based on the total mass of the at least one polyurethane urea, of at least one different polyol than b) having a number-average molecular weight M n of ≥500 and ≤6000 g/mol and a mean hydroxyl functionality of ≥1.5 and ≤4,

wherein the at least one polyurethane urea is dissolved in a solvent or solvent mixture,
wherein the solvent consists of one or more monohydroxy-functional alcohols or a solvent mixture consisting of organic solvents containing >80% by weight, based on the total mass of the solvent mixture, of at least one monohydroxy-functional alcohol.

2. The process according to claim 1 , wherein component b) is a poly(tetramethylene glycol) polyether polyol.

3. The process according to claim 1 , wherein component a) is selected from the group consisting of aliphatic and cycloaliphatic diisocyanates having at least one isocyanate group bonded to a secondary or tertiary carbon atom.

4. The process according to claim 1 , wherein component a) is selected from the group consisting of isophorone diisocyanate (IPDI) and bis(4,4′ isocyanatocyclohexyl) methane (H12-MDI).

5. The process according to claim 1 , wherein component c) is selected from amines having at least two isocyanate-reactive amino groups bonded to primary or secondary carbon atoms.

6. The process according to claim 1 , wherein component c) comprises a diamine of symmetric structure.

7. The process according to claim 1 , wherein component c) is selected from the group consisting of ethylenediamine and bis(4,4′ isocyanatocyclohexyl) methane (H12-MDA).

8. The process according to claim 1 , wherein the solvent mixture contains ≥99% by weight of monohydroxy-functional alcohols.

9. The process according to claim 1 , wherein the monohydroxy-functional alcohol is selected from the group consisting of ethanol and isopropanol and mixtures thereof.

10. The process according to claim 1 , further including preparing the at least one polyurethane urea by converting components a) and b) and optionally d) and f) into an NCO-terminated prepolymer in a first step and reacting the NCO-terminated prepolymer of the first step with component c) and optionally components d) and e).

11. The process according to claim 10 , wherein the NCO-terminated prepolymer is initially charged and component c) and optionally components d) and e) are added.

12. The process according to claim 10 , wherein the molar ratio of isocyanate-reactive groups of component c) to the free NCO groups of the prepolymer is ≥70% and ≤95%.

13. The process according to claim 1 , further including applying the dissolved at least one polyurethane urea to one of a textile material and a leather and coagulating the at least one polyurethane urea upon or within the one of the textile material and leather.

14. One of a textile and a leather coating obtained by the process according to claim 1 .

15. A polyurethane urea formed from
a) at least one of an araliphatic, an aliphatic and a cycloaliphatic diisocyanate,
b) at least one polyether polyol having a number-average molecular weight M n of ≥400 and ≤6000 g/mol, determined by means of gel permeation chromatography (GPC) in tetrahydrofuran (THF) at 23° C., and a mean hydroxyl functionality of ≥1.5 and ≤4,
c2) at least one amino-functional compound selected from symmetric diamines having at least two isocyanate-reactive amino groups bonded to primary or secondary carbon atoms,
d) optionally, at least one alcohol having at least two hydroxyl groups and a molar mass of ≥60 and ≤399 g/mol,
e) optionally, at least one compound having a group reactive toward isocyanate groups,
f) optionally, ≤20% by weight, based on the total mass of the polyurethane urea, of at least one different polyol than b) having a number-average molecular weight M n of ≥500 and ≤6000 g/mol and a mean hydroxyl functionality of ≥1.5 and ≤4,

wherein the polyurethane urea is dissolved in a solvent or solvent mixture, wherein the solvent consists of one or more monohydroxy-functional alcohols or a solvent mixture consisting of organic solvents containing ≥92% by weight, based on the total mass of the solvent mixture, of at least one monohydroxy-functional alcohol.

16. The polyurethane urea according to claim 15 , wherein component c) is selected from the group consisting of ethylenediamine and bis(4,4′ isocyanatocyclohexyl) methane (H12-MDA).

17. A process for coating of substrates, comprising including the polyurethane urea according to claim 15 in a coating applied to a substrate.

18. A process for production of free films, comprising applying the polyurethane urea according to claim 15 to a shaped body and coagulating the polyurethane urea.

Assignees

• Covestro Deutschland Ag

Inventors

• Dörr Sebastian
• Viala Sophie
• Michaelis Thomas

Classifications

• C08G18/4238

  derived from dicarboxylic acids and dialcohols · CPC title

• C08G18/12

  using two or more compounds having active hydrogen in the first polymerisation step · CPC title

• C08G18/73

  acyclic · CPC title

• C08G18/4018

  Mixtures of compounds of group C08G18/42 with compounds of group C08G18/48 · CPC title

• D06N3/146

  characterised by the macromolecular diols used · CPC title