Patent ID: 8278548

Claim:
A photovoltaic array backsheet comprising: an acrylic film comprising: a multi-stage acrylic polymer comprising from 10% to 75% by weight, based on the weight of said multi-stage polymer, first polymer comprising, as copolymerized units, from 0% to 20% by weight, based on the weight of said first polymer, C1-C6 alkyl methacrylate, said methacrylate having a homopolymer glass transition temperature (“Tg”) of from 60° C. to 120° C. and from 80% to 100% by weight, based on the weight of said first polymer, C1-C12 alkyl acrylate, said acrylate having a homopolymer Tg of lower than 10° C.; and from 25% to 90% by weight, based on the weight of said multi-stage polymer, second polymer formed in the presence of said first polymer comprising, as copolymerized units, from 50% to 100% by weight, based on the weight of said second polymer, C1-C6 alkyl methacrylate, said methacrylate having a homopolymer glass transition temperature (“Tg”) of from 60° C. to 120° C.; from 0% to 20% by weight, based on the weight of said second polymer, C1-C12 alkyl acrylate, said acrylate having a homopolymer Tg of lower than 10° C., and from 0% to 30% by weight, based on the weight of said second polymer, of a polymer having a homopolymer Tg of higher than 120° C.; and from 1% to 20%, by weight based on the weight of said film, pigment; and affixed thereto, a polyester layer.