Radiation-curable coating composition, method for producing scratch-resistant coatings, use of the coating composition, and substrate coated with a coating composition

Patent metadata

Field	Value
Publication number	US-10465092-B2
Application number	US-201716071562-A
Country	US
Kind code	B2
Filing date	Jan 16, 2017
Priority date	Jan 21, 2016
Publication date	Nov 5, 2019
Grant date	Nov 5, 2019

Abstract

The present invention relates to a radiation-curable coating composition, especially for producing a scratch-resistant coating on polycarbonate surfaces, comprising at least one urethane acrylate of an isocyanurate trimer of 1,6-hexamethylene diisocyanate and butanediol monoacrylate. The invention also relates to a method for producing scratch-resistant coatings on polycarbonate surfaces, to the use of the coating composition, and to a substrate coated accordingly.

First claim

What is claimed is:

1. A radiation-curable coating composition, comprising:
i) 45.0 to 59.0 wt % of a urethane acrylate prepared from an isocyanurate trimer of 1,6-hexamethylene diisocyanate and butanediol monoacrylate, wherein the isocyanurate trimer has an NCO content in a range of 19.6 to 24.0 wt % and an equivalent weight of 175 to 214, and the urethane acrylate has a weight ratio of the isocyanurate trimer to the butanediol monoacrylate in a range of 1.0:0.65 to 1.0:0.9;
ii) 25.0 to 37.0 wt % of a tetrafunctional polyester acrylate monomer;
iii) 8.0 to 12.0 wt % of a component A selected from the group consisting of a diol diacrylate ester, a monoacrylate ester, and mixtures thereof;
iv) 2.3 to 3.5 wt % of a photoinitiator;
v) 2.1 to 3.1 wt % of a reactive acryloyltriazole UV absorber;
vi) 1.5 to 2.0 wt % of a nonreactive UV absorber;
vii) 0.7 to 1.0 wt % of a sterically hindered amine;
viii) 0.4 to 0.9 wt % of a flow control additive;
where the weight percentage ranges are based on a sum of the solid content of components i) to viii), their sum making 100 wt %.

2. The coating composition of claim 1 , which comprises 45.0 to 55.0 wt % of the urethane acrylate, based on a sum of the solids contents of components i) to viii).

3. The coating composition of claim 1 , wherein the tetrafunctional polyester acrylate monomer has an ether bond.

4. The coating composition of claim 1 , wherein component iii) is a diol diacrylate ester.

5. The coating composition of claim 1 , wherein the component iii) is a diol diacrylate ester having 2 to 12 carbon atoms in the longest carbon chain.

6. The coating composition of claim 1 , wherein the photoinitiator comprises a phosphorus-containing compound.

7. The coating composition of claim 1 , wherein the photoinitiator comprises a mixture of a phosphorus-containing compound and an aromatic α-hydroxy ketone.

8. The coating composition of claim 1 , wherein the reactive acryloyltriazole UV absorber is an acryloylphenolbenzotriazole.

9. The coating composition of claim 1 , wherein the sterically hindered amine is a diester of sebacic acid.

10. The coating composition of claim 1 , which is curable with UV radiation.

11. The coating composition of claim 1 , which is a clearcoat material.

12. A method for producing a scratch-resistant coating on a polycarbonate surface, the method comprising:
i) applying the coating composition of claim 1 to a polycarbonate surface, and
ii) curing the coating composition with UV radiation.

13. The method of claim 12 , wherein the scratch-resistant coating has a dry film thickness in a range of 8 to 25 μm.

14. A method for protecting a vehicle headlamp from scratches, effects of weathering, or both scratches and effects of weathering, the method comprising:
i) coating the vehicle headlamp with the coating composition of claim 1 .

15. An article comprising a substrate, wherein the substrate is coated with the coating composition of claim 1 , and wherein the coating composition is cured.

Assignees

• Basf Coatings Gmbh

Inventors

• Kauffer Isabelle
• Klein Guenter
• Mayenfels Peter
• Wenking Ulrike
• Leitner Thomas

Classifications

• C08F220/343

  in the form of urethane links · CPC title

• C08F222/102

  of dialcohols, e.g. ethylene glycol di(meth)acrylate or 1,4-butanediol dimethacrylate · CPC title

• C08J7/0427

  with only one layer of a composition containing a polymer binder (with more layers C08J7/042) · CPC title

• C09D151/08

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

• C08J2475/16

  having terminal carbon-to-carbon unsaturated bonds · CPC title