Abrasion resistant polyurethane coatings for rigid plastics
AssigneePPG Industries, Inc.
InventorCharles R. Coleman
Life of this patent
Estimating the term…
Abstract
A method is disclosed for casting a colorless, single phase liquid reaction mixture comprising an aliphatic diisocyanate and a polyester polyol against a rigid transparent plastic and curing at a sufficiently rapid rate at temperatures of about 175.degree. to 275.degree. F. (about 79.degree. to 135.degree. C.) to form a relatively soft, resilient, abrasion resistant branched polyurethane coating without warpage or deterioration of the rigid plastic. The polyesterurethane coatings disclosed are characterized by durometer values at 70.degree. F. between Shore A 50 and Shore D 80, and molecular weights between branch points between 1000 and 13,000.
Claims9
An abrasion resistant branched polyurethane coated rigid plastic transparency comprising:
- a. a transparent rigid plastic substrate;
- and
- b. an abrasion resistant transparent branched polyurethane coating at least 5 mils thick formed from the reaction of an aliphatic diisocyanate and a polyol comprising a polyester polyol, said polyurethane having a durometer value at 70.degree. F. between Shore A 50 and Shore D 80 and said polyol comprising sufficient triol to produce a branched polyurethane with a molecular weight between branch points between 1000 and 13,000
Dependencies are inferred from the claim text.