Matthew J Snyder

US Patent:

60110805, Jan 4, 2000

Filed:

Aug 19, 1998

Appl. No.:

9/136184

Inventors:

Andrew T. Daly - Sinking Springs PA
Jeno Muthiah - Wernersville PA
Richard P. Haley - Reading PA
Owen H. Decker - Wyomissing PA
Eugene P. Reinheimer - Wyomissing PA
Matthew B. Snyder - Coatesville PA

Assignee:

Morton International, Inc. - Chicago IL

International Classification:

C08F 246

US Classification:

522107

Abstract:

This invention provides a UV curable powder coating composition comprising a particulate blend of a non-crystalline unsaturated polyester base resin, a crystalline unsaturated crosslinker resin co-polymerizable with the base resin, and a photoinitiator, that exhibits reduced or eliminated hazing in the cured coating formed therefrom upon being cured at low temperatures demanded by certain heat sensitive substrates. This is accomplished by incorporating in the powder composition a recrystallization inhibitor which is comprised of a crystalline epoxy resin. When this powder blend is melted for curing, all of the crystalline resin species tend to separate and recrystallize out of the molten powder slower and less completely than they do in the absence of the recrystallization inhibitor. This prevents a visible haze from quickly developing on the surface of the molten coating before the coating can be cured with UV radiation.

US Patent:

61368822, Oct 24, 2000

Filed:

Jul 8, 1999

Appl. No.:

9/349074

Inventors:

Andrew T. Daly - Sinking Springs PA
Jeno Muthiah - Wernersville PA
Richard P. Haley - Reading PA
Owen H. Decker - Wyomissing PA
Eugene P. Reinheimer - Wyomissing PA
Matthew B. Snyder - Coatesville PA

Assignee:

Morton International Inc. - Chicaog IL

International Classification:

C08F 246
C08F 248

US Classification:

522107

Abstract:

This invention provides a UV curable powder coating composition comprising a particulate blend of a non-crystalline unsaturated polyester base resin, a crystalline unsaturated crosslinker resin co-polymerizable with the base resin, and a photoinitiator, that exhibits reduced or eliminated hazing in the cured coating formed therefrom upon being cured at low temperatures demanded by certain heat sensitive substrates. This is accomplished by incorporating in the powder composition a recrystallization or haze inhibitor which is comprised of a crystalline epoxy resin. When this powder blend is melted for curing, the crystalline crosslinker resin visually appears to separate and recrystallize out of the molten powder less completely than it does in the absence of the recrystallization or haze inhibitor. This prevents a visible haze from developing on the surface of the coating upon curing with UV radiation.