摘要 |
<p>Epoxide resins, which polymerize on exposure to actinic radiation, have, per average molecule, at least two photopolymerizable groups and also at least two 1,2-epoxide groups, one or more such epoxide groups being contained in units of formula <IMAGE> Photopolymerizable epoxide resins are commonly prepared by introduction of photopolymerizable groups into a molecule of an epoxide resin by reaction with some of the epoxide groups: the modified resin, having a low epoxide group content, usually exhibits poorer adhesion and lower glass transition temperature than would otherwise be the case. In the new resins, secondary hydroxyl groups generated on introduction of the photopolymerizable groups have been converted into glycidyl ether groups, thus they have a higher epoxide content.</p> |