Clear coating compositions with improved scratch resistance

• US 20070244258A1
• Filed: 03/29/2006
• Published: 10/18/2007
• Est. Priority Date: 03/29/2006
• Status: Abandoned Application

• Current Assignee: PPG Industries Ohio Incorporated (Nouryon BV)
• Original Assignee: PPG Industries Ohio Incorporated (Nouryon BV)
• Inventors: Swarup, Shanti, Schwartzmiller, Davina, Simpson, Dennis, Olson, Kurt, Sadvary, Richard
• Application Number:
  US11/392,126
• Publication Number:
  US 20070244258A1
• Time in Patent Office: Days
• US Class Current: 525/165
• CPC Class Codes: C08G 18/4063 Mixtures of compounds of group C08G18/62 with other macromolecular compounds
• CPC Class Codes: C08G 18/4233 derived from polymerised higher fatty acids or alcohols
• CPC Class Codes: C08G 18/4241 from dicarboxylic acids and dialcohols in combination with polycarboxylic acids and/or polyhydroxy compounds which are at least trifunctional
• CPC Class Codes: C08G 18/792 formed by oligomerisation of aliphatic and/or cycloaliphatic isocyanates or isothiocyanates
• CPC Class Codes: C08J 2467/00 Characterised by the use of polyesters obtained by reactions forming a carboxylic ester link in the main chain of polyester-amides C08J2477/12; of polyester-imides C08J2479/08; Derivatives of such polymers
• CPC Class Codes: C08J 7/0427 with only one layer of a composition containing a polymer binder with more layers C08J7/042
• CPC Class Codes: C08J 7/046 Forming abrasion-resistant coatings; Forming surface-hardening coatings
• CPC Class Codes: C08K 9/06 with silicon-containing compounds
• CPC Class Codes: C08L 2666/04 Macromolecular compounds according to groups C08L7/00 - C08L49/00, or C08L55/00 - C08L57/00; Derivatives thereof
• CPC Class Codes: C08L 2666/14 Macromolecular compounds according to C08L59/00 - C08L87/00; Derivatives thereof
• CPC Class Codes: C08L 2666/16 Addition or condensation polymers of aldehydes or ketones according to C08L59/00 - C08L61/00; Derivatives thereof
• CPC Class Codes: C08L 2666/54 Inorganic substances
• CPC Class Codes: C09D 133/066 containing -OH groups
• CPC Class Codes: C09D 167/00 Coating compositions based on polyesters obtained by reactions forming a carboxylic ester link in the main chain based on polyester-amides C09D177/12; based on polyester-imides C09D179/08; Coating compositions based on derivatives of such polymers
• CPC Class Codes: C09D 175/04 Polyurethanes

Abstract

A clear coating composition for use over a colored basecoat having improved scratch resistance is disclosed. The coating composition comprises a film-forming polymer and a curing agent. The improvement is due to the incorporation in the clear coating composition of an adjuvant resin having functional groups reactive with the curing agent and positioned between the functional groups a moiety having a hydrocarbon chain of at least 10 contiguous carbon atoms.

Claims

1. A clear coating composition for use over a colored basecoat comprising:

(a) a polymeric film-forming material having reactive functional groups,

(b) a curing agent having functional groups reactive with the functional groups of (a), and optionally

(c) inorganic particles, and

(d) an adjuvant resin having 2 or more terminal functional groups reactive with the functional groups of (b) and positioned between the terminal functional groups a moiety having a hydrocarbon chain of at least 10 contiguous carbon atoms, the polymer having a functional group equivalent weight of 90 to 500;

wherein when the coating composition is applied to a substrate and cured, the cured coating is characterized as having a Fischer Hardness Value of 90 to 160.

2. The composition of claim 1 containing inorganic particles and when cured having an initial 20°

gloss of at least 70 and after scratch testing retaining greater than 40 percent of the initial 20°

gloss.

3. The composition of claim 1 in which the Fischer Hardness Value is between 100 and 140.

4. The composition of claim 1 in which the adjuvant resin has more than two terminal functional groups.

5. The composition of claim 1 in which the functional groups of (d) are active hydrogen groups.

6. The composition of claim 5 in which the active hydrogen groups are hydroxyl groups.

7. The composition of claim 1 in which the adjuvant resin (d) is a polyester prepared from a polycarboxylic acid and a polyol.

8. The composition of claim 7 in which the moiety having a hydrocarbon chain of at least 10 contiguous carbon atoms is derived from the polycarboxylic acid.

9. The composition of claim 1 in which the moiety positioned between the terminal active hydrogen groups is a hydrocarbon chain containing at least 16 carbon atoms.

10. The composition of claim 6 in which the hydroxyl groups are derived from a triol.

11. The composition of claim 10 in which the polyol is selected from trimethylolpropane and pentaerythritol.

12. The composition of claim 7 comprising a mixture of polycarboxylic acids including the polycarboxylic acid having a moiety containing a hydrocarbon chain of at least 16 contiguous carbon atoms and a polycarboxylic acid having a hydrocarbon chain of less than 10 contiguous carbon atoms.

13. The composition of claim 12 which contains an additional polycarboxylic acid selected from linear aliphatic polycarboxylic acids having a hydrocarbon chain with less than 10 contiguous carbon atoms and a cycloaliphatic polycarboxylic acid.

14. The composition of claim 7 in which the polycarboxylic acid is a fatty polycarboxylic acid.

15. The composition of claim 14 in which the fatty dicarboxylic acid has a hydrocarbon chain of from 16 to 40 contiguous carbon atoms.

16. The composition of claim 1 in which (d) is present in the composition in amounts of 1 to 50 percent by weight based on weight of resin solids.

17. The composition of claim 16 in which (d) is present in the composition in amounts of 2 to 40 percent by weight based on weight of resin solids.

18. The composition of claim 1 as a one-package system comprising a polymeric film-forming material containing hydroxyl groups and an aminoplast resin curing agent.

19. A multilayer composite coating comprising a colored basecoat and a clear topcoat, the clear topcoat being deposited on the colored basecoat from the clear coating composition of claim 1.