| 摘要 |
Compounds having repeating units of the formula I (* CHEMICAL STRUCTURE *) (I) in which R1 is an alkylene, cycloalkylene, alkenylene, alkynylene, or arylenebisalkyl group, in which one or more aliphatic CH2 groups may be replaced by oxygen or sulfur atoms, R2 is an alkyl, alkenyl, alkynyl, cycloalkyl, alkoxyalkyl, aryl, aralkyl or aryloxyalkyl radical, R3 is an alkyl or aryl radical, X is -CO-, -O-CO- or -NH-CO-, and n is an integer greater than 1, especially from 3 to 50. are cleavable by acid and, in combination with photolytic acid donors and alkali-soluble binders, are constituents of positive-working mixtures which are used especially in recording materials for UV radiation and high-energy radiation. The materials are distinguished by a high resolution in conjunction with high image contrast. |
