Photo-curable resin composition, patterning process, and substrate protecting film

A photo-curable resin composition comprising

• (A) an organosiloxane-bearing polymer comprising recurring units of the following general formula (1):
• 14
• wherein R1 to R4 are each independently a monovalent hydrocarbon radical of 1 to 8 carbon atoms, n is an integer of 1 to 1,000, and X is a radical selected from the group consisting of
• 15
• and having a weight average molecular weight of 500 to 200,000,
• (B) at least one member selected from the group consisting of formalin-modified or formalin-alcohol-modified amino condensates, phenol compounds having on the average at least two methylol or alkoxymethylol radicals per molecule, and epoxy compounds having on the average at least two epoxy radicals per molecule,
• (C) a photoacid generator, and
• (D) a silicon compound of the following general formula (2):
• (R11)mSi(OR 12)4−m (2)
• wherein R11 is a substituted or unsubstituted monovalent hydrocarbon radical of 1 to 9 carbon atoms, R12 is an alkyl radical of 1 to 4 carbon atoms, R11 and R12 may be the same or different, m is an integer of 0 to 2, or a partial hydrolytic condensate thereof.