Patent ID: 7211368

Claim:
A liquid stereolithography resin comprising a first urethane acrylate oligomer, a first acrylate monomer, a polymerization modifier, a second urethane acrylate oligomer different from the first urethane acrylate oligomer, and a stabilizer; wherein the first urethane acrylate oligomer is an aliphatic polyester urethane diacrylate oligomer, wherein the first acrylate monomer is ethoxylated (3) trimethylolpropane acrylate, and the polymerization modifier is selected from the group consisting of isobornyl acrylate, ethoxylated (5) pentaerythritol tetraacrylate, an aliphatic urethane acrylate, tris-(2-hydroxyethyl)isocyanurate triacrylate, and mixtures thereof, wherein the resin includes 5–35 weight % an aliphatic polyester urethane diacrylate oligomer and 0.5–25 weight % ethoxylated (3) trimethylolpropane acrylate, wherein the resin includes 15–45 weight % ethoxylated (5) pentaerythritol tetraacrylate.