| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain the subject low-viscosity novolak type resin useful as an electrical and electronic material such as an adhesive, a coating material, an insulating material or a laminate by regulating the area percentage of a dinuclear substance in a gel permeation chromatography(GPC) to a specific value or above. SOLUTION: This resin is obtained by regulating the area percentage of a dinuclear substance in a GPC of to >=15%, preferably >=30%. The resin is preferably an o-cresol novolak type resin. The viscosity of the resin is preferably <=0.5 P. The resin is obtained by carrying out a condensing reaction of, e.g. phenols (o-cresol) with aldehydes or ketones (e.g. formalin) in the presence of an acidic catalyst such as p-toluenesulfonic acid while controlling the charging ratio of the phenols to the aldehydes or ketones so as to provide the value or above of the area percentage of the dinuclear substance in the GPC, providing novolaks and then epoxidizing the resultant novolaks.</p> |
