PROCESS FOR FORMATION OF INSULATING LAYER OF SILYLATED POLYSILSESQUIOXANE ON ELECTRONIC CIRCUIT BOARD

摘要

A lower alkyl polysilsesquioxane having a general formula …… wherein R is lower alkyl, preferably CH3 or C2H5, and n is an integer equal to about 50 to about 10,000, prepared by (a) dissolving a lower alkyl trifunctional silane in an organic solvent at a temperature of -20 DEG C to -50 DEG C to form an organic solution thereof: (b) hydrolysing the lower alkyl trifunctional silane by dropping water into the organic solution at a temperature of -20 DEG C to -50 DEG C under an inert gas pressurised at 1,000 to 3,000 Pa; and (c) gradually heating the organic solution together with a water phase lying therebeneath up to a temperature of 60 DEG C to 100 DEG C under an inert gas pressurised at 1,000 to 3,000 Pa. …Also, a flat surfaced insulating layer of a silylated organopolysilsesquioxane having a general formula …… wherein R<1> and R<2> are each selected from alkyl and phenyl (preferably methyl or ethyl), and n is an integer equal to about 50 to about 2,000, preferably about 50 to about 500, formed on a circuit board having stepwise differences in height thereon, by applying an organic solution of the polymer; evaporating the solvent; and melting the polymer to flatten the surface of the polymer and curing the polymer.