| abstract |
A photocurable, ethylenically-unsaturated, water-soluble oligomer comprising the reaction product of 100 parts by weight of a dextrin compound, and 35 to 70 parts by weight of at least one ethylenically-unsaturated monomer capable of reacting with at least one hydroxyl group of the dextrin compound, the oligomer having an average in the range of 0.1 to 0.7 ethylenically-unsaturated moiety per anhydroglucose unit and an equivalent weight of 440 to 990, and at least 75 weight percent of the oligomer is water soluble at 20 DEG C. in a concentration of at least 2.5 percent by weight. The oligomer when photocured in combination with an ethylenically-unsaturated monomer is useful as a photoresist in positive-acting, water-developable, lithographic printing plates. |