Patent ID: 8309653

Claim:
A composition comprising: an isocyanate resin component selected from the group consisting of hydrophilic aliphatic diisocyanate monomers, hydrophilic aliphatic diisocyante homopolymers, hydrophilic aliphatic diisocyanate oligomers, and combinations thereof, and an acrylic polyol resin component, wherein at least one of the isocyanate resin component and the acrylic polyol resin component is in a water-based carrier, and further wherein a) the isocyanate resin component comprises 20-40% by weight of the composition, b) the acrylic polyol resin component comprises 10-20% by weight of the composition, and c) the isocyanate resin component and the acrylic polyol resin component are present in relative amounts with respect to each other such that when the isocyanate resin component and the acrylic polyol resin component are combined with one another under ambient conditions, the composition cures to form a material having a write-erasable surface, which material has at least one characteristic selected from the group consisting of: a Sward hardness of greater than about 25; a Taber abrasion of less than 150 mg/thousand cycles; the elongation at break between about 5 percent and about 400 percent; the sag resistance between about 4 mils to about 24 mils; a contact angle measured from the surface of the material using deionized water of less than about 150 degree; and combination thereof; which material is further characterized in that, when its surface is written on with a marking material comprising a colorant and a solvent, the solvent comprising one or more of water, alcohols, alkoxy alcohols, ketones, ketonic alcohols, esters, acetates, mineral spirits, or mixtures thereof, the marking material can be erased from the surface of the write-erasable material to be substantially invisible for more than 100 cycles of writing and erasing at the same position.