Coating compositions incorporating ingredients having secondary amine, hydroxyl and isocyanate functionality
View Patent ↗The present invention provides coating compositions with excellent curing performance. Curing can occur very rapidly for excellent cycle time, yet with minimal (if any) foaming. A preferred catalyst system helps to provide excellent initial and follow through cure through the entirety of the coating thickness, even with respect to in-mold coating (IMC) applications. Preferred aspects of the invention provide a composition having zero, or nearly zero, emissions of volatile organic compounds (VOC) when applied and cured.
1. A coating composition derived from ingredients, comprising:
a) a secondary amine component;
b) a 100% solids polyisocyanate component; and
c) a catalyst system, comprising:
(i) a first catalyst comprising catalytically active aluminum; and
(ii) a second catalyst comprising a catalytically active zirconium,
wherein the first catalyst and the second catalyst are present in a ratio of 1:10 to 10:1 parts by weight, and wherein the composition is applied to a mold surface as an in-mold coating.
2. A coating composition according to claim 1 , further comprising d) a polyol component.
3. The coating composition of claim 1 , wherein
the secondary amine component comprises at least one compound according to the formula
X 1 —[NH—Z 1 —(COOR 1 ) m ] n
wherein each R 1 independently is a monovalent moiety other than H that is substantially inert with respect to being co-reactive with NCO functionality at a temperature of 150° C. or less, X 1 is a moiety having a valency of n that is substantially inert with respect to being co-reactive with NCO functionality at a temperature of at least 150° C. or less, Z 1 is a single bond or linking group with a valence of m+1; m is 1 to 20; and n is at least 1 and no greater than 20.
4. A cured coating obtained from a composition of claim 1 .
5. A coating composition according to claim 1 , further comprising an air release additive.
6. A coating composition according to claim 1 , further comprising a thixotrope.
7. The composition of claim 1 , wherein the first and second catalysts are present in a ratio of 1:1.5 to 1:2.
8. The composition of claim 1 , wherein the first catalyst is an aluminum chelate in 2, 4-pentanedione, and the second catalyst is a zirconium chelate in 2,4-pentanedione.