Carboxy-functional, polyether-based reaction products and aqueous basecoat materials comprising the reaction products

Patent metadata

Field	Value
Publication number	US-10889090-B2
Application number	US-201616060482-A
Country	US
Kind code	B2
Filing date	Nov 30, 2016
Priority date	Dec 9, 2015
Publication date	Jan 12, 2021
Grant date	Jan 12, 2021

Abstract

The present invention relates to a pigmented aqueous basecoat material comprising a polyether-based reaction product which is preparable by reaction of (a) at least one cyclic carboxylic anhydride comprising a free carboxylic acid group and/or the halide of a carboxylic acid group
with
(b) at least one polyether of the general structural formula (I)

in which

R is a C 3 to C 6 alkylene radical and n is selected accordingly such that the polyether (b) possesses a number-average molecular weight of 800 to 4000 g/mol, the components (a) and (b) being used in the reaction in a molar ratio of 0.7/2.3 to 1.6/1.7 and the resulting reaction product possessing an acid number of 10 to 50 mg KOH/g.

First claim

What is claimed is:

1. A pigmented aqueous basecoat material, comprising
a polyether-based reaction product prepared by reacting
(a) trimellitic anhydride
with
(b) at least one polyether of formula (I)

wherein
R is a C 4 alkylene radical and n is selected accordingly such that the polyether (b) possesses a number-average molecular weight of from 1000 to 2900 g/mol,
wherein a molar ratio of (a) to (b) ranges from 0.45/1 to 0.55/1 and the polyether-based reaction product has an acid number of 10 to 30 mg KOH/g.

2. The basecoat material of claim 1 , wherein the polyether (b) possesses a number-average molecular weight of 1200 to 2900 g/mol.

3. The basecoat material of claim 1 , wherein R in the formula (I) comprises a tetramethylene radical.

4. The basecoat material of claim 1 , wherein the polyether-based reaction product possesses a number-average molecular weight of 1500 to 15,000 g/mol.

5. The basecoat material of claim 1 , wherein a sum total of weight-percentage fractions, based on a total weight of the basecoat material, of all polyether-based reaction products is 0.1 to 20 wt %.

6. The basecoat material of claim 1 , further comprising
a melamine resin and
a polyurethane resin that is grafted with olefinically unsaturated monomers and comprises hydroxyl groups.

7. A polyether-based reaction product, obtained by reacting
(a) trimellitic anhydride
with
(b) at least one polyether of formula (I)

wherein
R is a C 4 alkylene radical and n is selected accordingly such that the polyether (b) possesses a number-average molecular weight of from 1000 to 2900 g/mol,
wherein a molar ratio of (a) to (b) ranges from 0.45/1 to 0.55/1 and the polyether-based reaction product has an acid number of 10 to 30 mg KOH/g.

8. A method for improving adhesion and stonechip resistance of a paint system produced from a pigmented aqueous basecoat material, the method comprising:
introducing the polyether-based reaction product of claim 7 into the basecoat material.

9. A method for producing a multicoat paint system, the method comprising
(1) applying the basecoat material of claim 1 to a substrate,
(2) forming a basecoat from the basecoat material,
(3) applying a clearcoat material to the basecoat, and subsequently
(4) curing the basecoat together with the clearcoat.

10. The method of claim 9 , wherein the substrate is a metallic substrate coated with a cured electrocoat, and all coats applied to the electrocoat are cured jointly.

11. The method of claim 9 , wherein the substrate is a multicoat paint system which possesses defects.

12. A multicoat paint system, produced by the method of claim 9 .

13. A multicoat paint system with defects, produced by forming the defects on the multicoat paint system of claim 12 as a result of external mechanical influences.

Assignees

• Basf Coatings Gmbh

Inventors

• Steinmetz Bernhard
• Hoffmann Peter
• Reuter Hardy

Classifications

• C09D151/08

  grafted on to macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds · CPC title

• C09D5/08

  Anti-corrosive paints · CPC title

• C08J2351/08

  grafted on to macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds · CPC title

• C08G63/123

  the acids or hydroxy compounds containing carbocyclic rings · CPC title

• C08J7/043 Primary

  Improving the adhesiveness of the coatings per se, e.g. forming primers (adhesives in the form of films or foils characterised by the primer layers between the polymer carriers and the adhesives C09J7/50) · CPC title