| 摘要 |
1,217,844. Polyurethane coating composition; polymer compositions. COLUMBIA RIBBON & CARBON MFG. CO. Inc. 25 Nov., 1968 [25 Nov., 1967], No. 53710/67. Headings C3P and C3R. [Also in Division D2] In making a pressure-sensitive transfer element (see Division D2) a composition of a moisture-curable, saturated, polyester-based urethane prepolymer in solvents (methyl ethyl ketone and ethyl acetate in the examples), which may also contain polyvinyl acetate, is coated on to a substrate and the solvents evaporated. A further composition comprising a ground pigment paste (oil and black toner with a wetting agent e.g. lecithin), methyl ethyl ketone, toluene and a vinyl chloride/vinyl acetate copolymer is applied over the urethane layer, and the solvents evaporated to give a microporous polymer layer containing ink in its pores. |
