A photocurable resin composition comprising
(a) 10 to 90 parts by weight of a urethane acrylate resin which is obtainable by reacting a polyester in which an alicyclic dicarboxylic acid component accounts for 100 mole percent of the total acid component and an aliphatic diol having a side chain and/or alicyclic diol accounts for 60 to 100 mole percent of the total alcohol component while an aliphatic tri- or polyol accounts for 40 to 0 mole percent with (i) an aliphatic or alicyclic polyisocyanate and an active hydrogen compound containing a polymerizable unsaturated group or (ii) a monofunctional isocyanate compound containing a polymerizable unsaturated group within the molecule,
(b) 90 to 10 parts by weight of a non-aromatic crosslinking agent having at least one (meth)acryloyl group within the molecule, and (c) an effective amount of a photosensitizer to initiate a photopolymerization reaction between (a) and (b). The composition has a remarkably high degree of weather resistance corresponding to a weather-o-meter time of not less than 4,000 hours.
一种光固化
树脂组合物,包括
(a) 10 至 90 份(重量)聚
氨酯
丙烯酸酯
树脂,该
树脂可通过将脂环族二
羧酸组分占总酸组分的 100 摩尔%、具有侧链的脂肪族二元醇和/或脂 环族二元醇占总醇组分的 60 至 100 摩尔%、脂肪族三元或多元醇占 40 至 0 摩尔%的聚酯与(i)脂肪族或脂环族多
异氰酸酯和含有可聚合的不饱和活性氢化合物反应而得或多元醇占 40 至 0 摩尔%,(i) 脂肪族或脂环族多
异氰酸酯和含有可聚合不饱和基团的活性氢化合物,或 (ii) 分子中含有可聚合不饱和基团的单官能
异氰酸酯化合物、
(c) 有效量的光敏剂,以引发(a)和(b)之间的光聚合反应。该组合物具有极高的耐候性,其耐候性计时间不少于 4000 小时。