Patent ID: 8680171
Filing Date: 2014-03-25
Classification: B32B,H01L,Y02E

Abstract:
1. A method of encapsulating a photovoltaic cell comprising the step of curing an encapsulation composition, wherein said curing step comprises applying UV radiation at ambient pressure and temperature, the encapsulation composition being liquid at room temperature and comprising: at least one polyvinyl acetal resin which is a derivative of either polyvinyl acetate or vinyl acetate copolymer, wherein the polyvinyl acetal resin has repeating units of Formula I: wherein R is H or a substituted or unsubstituted organic radical, and Ac is an acetate group having the formula —(C═O)CH 3 , the polyvinyl acetal resin having a weight average molecular weight of about 10,000 to about 250,000, and wherein the weight percent of a is from 0 to about 80, the weight percent of b is from about 20 to about 90, the weight percent of c is from about 0 to about 10, and the weight percent of d is greater than 0 and up to about 30, wherein the total weight percent of a+b+c+d is 100 percent, and where N is from about 50 to about 1500, the resin comprising vinyl acetal units, and one or more ethylenically unsaturated monomers, oligomers, or a combination thereof, and at least one thermal free radical initiator or/and at least one photoinitiator.