High performance aqueous coating compositions

• US 7,834,086 B2
• Filed: 06/04/2007
• Issued: 11/16/2010
• Est. Priority Date: 06/02/2006
• Status: Active Grant

• Current Assignee: Swimc, LLC (The Sherwin-Williams Company)
• Original Assignee: Valspar Sourcing, Inc. (Sherwin-Williams Company)
• Inventors: Weber, Carl H, Killilea, T. Howard, Wildman, Michael C., Johnson, Bruce A.
• Primary Examiner(s): Sastri; Satya B
• Application Number:
  US11/757,916
• Publication Number:
  US 20070282046A1
• Time in Patent Office: 1,261 Days
• Field of Search: 525/902, 525/220, 524/261, 524/832
• US Class Current: 524/832
• CPC Class Codes: C08K 5/5415 containing at least one Si—O bond
• CPC Class Codes: C08K 5/5419 containing at least one Si—C bond
• CPC Class Codes: C08K 5/5435 containing oxygen in a ring
• CPC Class Codes: C08L 2312/08 by silane
• CPC Class Codes: C09D 133/02 Homopolymers or copolymers of acids; Metal or ammonium salts thereof
• CPC Class Codes: C09D 133/14 of esters containing halogen, nitrogen, sulfur or oxygen atoms in addition to the carboxy oxygen
• CPC Class Codes: Y10S 525/902 Core-shell
• CPC Class Codes: Y10T 428/31511 Of epoxy ether
• CPC Class Codes: Y10T 428/31663 As siloxane, silicone or silane
• CPC Class Codes: Y10T 428/31855 Of addition polymer from unsaturated monomers

Abstract

This invention relates to coating compositions that include water; a latex polymer and a silane coupling agent. The latex polymer preferably comprises acetoacetoxy functionality, or is a multistage latex, or is an acetoacetoxy functional multistage latex. The silane coupling agent is preferably a functionalized silane coupling agent (more preferably an epoxy-functional silane coupling agent). The compositions may be used to coat a variety of substrates, including wood, cement and fiber cement. Articles having the coating applied thereto are also provided.

Claims

1. A coating composition, comprising:

water;

a multistage latex polymer having acetoacetoxy functionality; and

at least about 0.25 weight % and less than about 10 weight %, based on the weight of the latex polymer, of a silane coupling agent that provides improved resistance to delamination from a cement substrate when a coating made from the composition is exposed for one hour at 60°

C. to 1,034 kPa pressure from an automotive tire tread section heated to 60°

C., wherein the silane coupling agent does not contain a functional group capable of reacting with another component of the coating composition.

2. The composition of claim 1, wherein the multistage latex polymer comprises at least one soft stage having a Tg between about −

65 and 30°

C. and at least one hard stage having a Tg between about 30 and 230°

C.

3. The composition of claim 2, wherein the multistage latex polymer comprises 50 to 90 weight % soft stage polymer morphology having a Tg between about −

5 and 25°

C. and 10 to 50 weight % hard stage polymer morphology having a Tg between about 30 and 105°

C., based on total polymer weight.

4. The composition of claim 2, wherein the multistage latex polymer has a gradient Tg.

5. The composition of claim 1, wherein the composition comprises at least 10 weight % multistage latex polymer, based on total solids of the composition.

6. The composition of claim 1, wherein the multistage latex polymer is made using from 0.5 to 10 weight % acetoacetoxy functional monomer based on the total weight of the multistage latex polymer.

7. The composition of claim 1, wherein the composition includes less than 10 weight % volatile organic compounds.

8. The composition of claim 1, wherein the composition further comprises a low VOC coalescent in an amount of at least 1 weight %.

9. The composition of claim 1, wherein the composition resists crush when two face-to-face coated embossed substrates are subjected to a pressure of 8 kg/cm².

10. The composition of claim 1, wherein the silane coupling agent is present in an amount of from 0.25 to 5 weight percent based on the weight of latex polymer.

11. The composition of claim 10, wherein the silane coupling agent is present in an amount of from 0.5 to 2 weight percent based on the weight of latex polymer.

12. The composition of claim 1, wherein the composition is in the form of a sealer layer atop a wood or porous substrate.

13. The composition of claim 1, wherein the composition is in the form of a sealer layer atop a cementitious substrate.

14. The composition of claim 1, wherein the composition is in the form of a topcoat layer atop a cementitious substrate.

15. The composition of claim 1, wherein the coating composition resists damage from hot tires.