Reaction product and pigmented basecoat material comprising said product

• US 10,457,830 B2
• Filed: 06/16/2015
• Issued: 10/29/2019
• Est. Priority Date: 07/01/2014
• Status: Active Grant

• Current Assignee: BASF Coatings GmbH (BASF SE)
• Original Assignee: BASF Coatings GmbH (BASF SE)
• Inventors: Steinmetz, Bernhard, Hoffmann, Peter, Reuter, Hardy
• Primary Examiner(s): Chin, Hui H
• Application Number:
  US15/322,336
• Publication Number:
  US 20170137662A1
• Time in Patent Office: 1,596 Days
• Field of Search: 524599
• CPC Class Codes: B05D 7/14 to metal, e.g. car bodies involving a chemical reaction between the metal and the coating C23
• CPC Class Codes: B05D 7/572 all layers being cured or baked together
• CPC Class Codes: C08F 136/06 Butadiene
• CPC Class Codes: C08F 279/02 on to polymers of conjugated dienes
• CPC Class Codes: C08G 81/027 containing polyester or polycarbonate sequences
• CPC Class Codes: C09D 151/003 grafted on to macromolecular compounds obtained by reactions only involving unsaturated carbon-to-carbon bonds C09D151/04, C09D151/06 take precedence
• CPC Class Codes: C09D 167/06 Unsaturated polyesters having carbon-to-carbon unsaturation
• CPC Class Codes: C09D 175/04 Polyurethanes

Abstract

The present invention relates to a pigmented aqueous basecoat material comprising a reaction product which is preparable by reaction of

• (a) at least one aliphatic linear polyester having two functional end groups (a.1), with
• (b) at least one diene polymer having two functional end groups (b.1),
• where at least one type of group (a.1) is reacted in a linking manner with at least one type of group (b.1), said components (a) and (b) are used in the reaction in a molar ratio of 2.3/0.7 to 1.7/1.6 and the resulting reaction product possesses a number-average molecular weight of 1000 to 15 000 g/mol.

Claims

1. A pigmented aqueous basecoat material, comprising:

a reaction product which is prepared by reaction of

(a) at least one aliphatic linear polyester having two functional end groups (a.1), with

(b) at least one diene polymer having two functional end groups (b.1),

wherein at least one type of group (a.1) is reacted in a linking manner with at least one type of group (b.1), said components (a) and (b) are used in the reaction in a molar ratio of 2.3/0.7 to 1.7/1.6 and the resulting reaction product possesses a number-average molecular weight of 1000 to 15 000 g/mol.

2. The pigmented aqueous basecoat material as claimed in claim 1, wherein the diene polymer (b) is a polybutadiene having two functional end groups and a number-average molecular weight of 500 to 5000 g/mol.

3. The pigmented aqueous basecoat material as claimed in claim 2, wherein the diene polymer comprises two hydroxyl groups as functional end groups.

4. The pigmented aqueous basecoat material as claimed in claim 1, wherein components (a) and (b) are used in a molar ratio of 2.1/0.9 to 1.8/1.5.

5. The pigmented aqueous basecoat material as claimed in claim 1, wherein the reaction product is prepared by ring-opening reaction of an aliphatic lactone with a diene polymer comprising two hydroxyl end groups, the molar ratio of aliphatic lactone to diene polymer being from 2/1 to 50/1.

6. The pigmented aqueous basecoat material as claimed in claim 5, wherein the aliphatic lactone the following formula (I):

7. The pigmented aqueous basecoat material as claimed in claim 6, wherein the lactone is epsilon-caprolactone.

8. The pigmented aqueous basecoat material as claimed in claim 5, wherein the molar ratio of the aliphatic lactone to diene polymer is from 5/1 to 40/ 1.

9. The pigmented aqueous basecoat material as claimed in claim1, wherein the sum total of the weight-percentage fractions, based on the total weight of the pigmented aqueous basecoat material, of all the reaction products is 0.1 to 30 wt %.

10. The pigmented aqueous basecoat material as claimed in claim 1, which comprises a polyurethane resin that is grafted with olefinically unsaturated monomers and that also comprises hydroxyl groups, and a melamine resin.

11. A method for producing a multicoat paint system comprising:

(1) applying a pigmented aqueous basecoat material to a substrate,

(2) forming a polymer film from the coating material applied in stage (1),

(3) applying a clearcoat material to the resulting basecoat film, and then

(4) curing the basecoat film together with the clearcoat film,

wherein a pigmented aqueous basecoat material as claimed in claim 1 is used in stage (1).

12. The method as claimed in claim 11. wherein the substrate is a metallic substrate coated with a cured electrocoat film, and all of the films applied to the electrocoat film are cured jointly.

13. A multicoat paint system obtained by the method as claimed in claim 11.

14. The pigmented aqueous basecoat material as claimed in claim 6, wherein n+m is from 2 to 6.

15. A method of improving stability of paint, the method comprising:

adding a reaction product to a paint that comprises a basecoat material,

wherein the reaction product is prepared by reaction of

(a) at least one aliphatic linear polyester having two functional end groups (a.1), with

(1) at least one diene polymer having two functional end groups (b.1),

wherein at least one type of group (a.1) is reacted in a linking manner with at least one type of group (b.1), said components (a) and (b) are used in the reaction in a molar ratio of 2.3/0.7 to 1.7/1.6 and the resulting reaction product possesses a number-average molecular weight of 1000 to 15 000 g/mol.