US 6,294,619 B1 · Stable powder coating compositions which produce consistent finishes

Abstract

The invention provides powder coatings that consistently produce durable finishes when cured, and are stable when uncured. These powder coatings of the invention include novel film forming systems. The novel film forming system, in turn, includes a polymer component and a crosslinker component. In one embodiment, the polymer component is novel; and, in another embodiment, both the polymer and crosslinker components are novel. The novel polymer component includes a novel polyester polyol. This novel polyester polyol includes the reaction product of a cycloaliphatic component and a polyfunctional isocyanurate component. The novel crosslinker component which can be used when practicing certain embodiments of this invention includes a novel, polyfunctional isocyanate compound which is at least partially blocked with at least one of the following: a polyhydroxy aromatic compound, or a mixture of a polyhydroxy aromatic compound and a hydroxy-functional ester compound.

Claims30

Dependent claims

A powder coating composition comprising a film forming resin system, wherein said film forming resin system comprises:

a. a polymer component comprising a polyester polyol which comprises the reaction product of:
i. a cycloaliphatic component which comprises the reaction product of:
(1) a cycloaliphatic acid, and
(2) a cyclic polyol, and
ii. a polyfunctional isocyanurate component which comprises at least one compound that has at least two groups reactive towards carboxylic groups, and
b. a crosslinker component capable of crosslinking said polyester polyol, said crosslinker component comprising a polyfunctional isocyanate which is at least partially blocked with at least one of the following:
i. a polyhydroxy aromatic compound having at least one of the following structures:
HO—Φ1—R1—Φ1—OH
where Φ1 consists of a phenylene group, and Rh is an alkylene group having 0 to 4 carbon atoms, or
HO—Φ2—OH
where Φ2 consists of a phenylene group or a naphthylene group, or
ii. a mixture of the polyhydroxy aromatic compound and a hydroxy-functional ester compound.

9 more elements

Dependencies are inferred from the claim text.

Stable powder coating compositions which produce consistent finishes

Life of this patent

Stable powder coating compositions which produce consistent finishes

Life of this patent

Abstract

Claims30