| 摘要 |
PURPOSE:To obtain the title adhesive suffering little decrease in resistance to soldering heat and little deterioration of applicability with time by dissolving an epoxy resin, a polyvinyl butyral, an isocyanate, and a melamine resin having a specified pH value in an organic solvent. CONSTITUTION:Melamine is reacted with formaldehyde at a molar ratio of 1:(1.5 to 4.0) under neutral or weakly alkaline conditions, if necessary, in the presence of a lower alcohol, and the pH is adjusted to a value of 5 to 7 with an acid, thus giving a melamine resin (A) having a pH of 5 to 7. 5-30wt.% epoxy resin (B) preferably comprising a bisphenol or novolak epoxy resin, 30-70wt.% polyvinyl butyral (C) preferably having a degree of butyralization of 60-65mol% and a degree of polymerization of 1,000 to 2,000, 1-15wt.% isocyanate (D) (e.g. diphenylmethane diisocyanate), and 10-50wt.% component A are dissolved in a solvent (E). |
