Patent ID: 9056519
Filing Date: 2015-06-16
Classification: B43L,C08G,C09D,Y10T

Abstract:
1. A method of forming a coating having a write-erasable surface on a substrate comprising: combining an isocyanate resin component and an acrylic polyol resin component in relative amounts with respect to each other to produce a composition, wherein the composition is in an organic solvent-based carrier, and further wherein a) the isocyanate resin component comprises 20-40% by weight of the composition, and b) the acrylic polyol resin component comprises 10-20% by weight of the composition; applying the composition to a substrate, to cure under ambient conditions so that a coating having a write-erasable surface is produced on the substrate, the coating being characterized by: a gloss finish greater than 65 when measured at 60°; an average surface roughness of less than 7,500 nm and a maximum surface roughness of less than 10,000 nm; a Sward hardness of greater than about 10; a Taber abrasion of less than 150 mg/thousand cycles; an elongation at break is between about 5 percent and about 400 percent; a sag resistance is between about 4 mils to about 24 mils; and a contact angle measured using deionized water of less than about 150 degree, and so that after the coating is marked with a marking material comprising a colorant and a solvent, the marking material can be erased from the write-erasable surface to be effectively invisible.