abstract |
A defoamer composition comprising (A) an organopolysiloxane containing an oxyalkylene group having an appropriate hydrophilic-hydrophobic balance, (B) another organopolysiloxane containing an oxyalkylene group serving as a surface active agent for component (C), (C) a dimethylpolysiloxane for retaining defoaming power, and (D) a silica filler can maintain defoaming power for a long time, for example, when it is added to a developer for exposed photosensitive resin which is subject to shearing stresses in the wash-out step. |