Abstract: A pressure-sensitive adhesive or pressure-sensitive adhesive tape for removing a foreign matter present on the surface of an article from the article, the pressure-sensitive adhesive having the property of curing with an actinic energy source to have a three-dimensional network molecular structure, a modulus of elasticity (as measured in accordance with JIS K 7127) before the curing of lower than 1 kg/mm.sup.2 and a modulus of elasticity after the curing of 1 kg/mm.sup.2 or higher, and a degree of volumetric shrinkage through the curing of 2% or higher.

Abstract: A siloxane-modified polyimide precursor which can be converted into a polyimide having excellent adhesion and moisture resistance is produced by simultaneously polymerizing a diaminosiloxane and a diamine containing no silicon atoms in its molecule with 3,3',4,4'-biphenyltetracarboxylic dianhydride, wherein the diaminosiloxane is used in an amount of 1 to 4 mole % per mole of the total diamino compounds and such that the silicon content in the final reaction product is 0.5 wt % or less. The thus obtained precursor solution is further heat aged to reduce the molecular weight of the precursor so that solution viscosity is decreased to a proper level suitable for coating operation.