| 摘要 |
PURPOSE: To prevent the whitening of a produced printing plate and the whitening of a solvent and to improve the solvent resistance, printing resistance and flexibility of the plate by using an acrylic ester copolymerized emulsion in place of vinyl acetate. CONSTITUTION: An aq. soln. of stilbazolium group added partially saponified PVA is prepd. and 20-45% of the aq. soln. is mixed with 2045% acrylic ester copolymerized emulsion, 5-20% reactive monomer having an acryloyl group, 5-20% reactive oligomer having methacryloyl groups and a photopolymn. initiator. For example, 1.0-4.25mol% stilbazolium groups are added to PVA having a saponification degree of 70-95% and a polymn. degree of 500-3,500 and 300g aq. soln. of the resultant PVA is mixed under stirring with 350g acrylic ester copolymerized emulsion, 98g reactive monomer having an acryloyl group to which 2g polymn. initiator has been added and 98g reactive oligomer having methacryloyl groups to which 2g polymn. initiator has been added. |
