| 摘要 |
1, 185, 540. Light-and heat-sensitive materials. KALLE A.G. Nov.17, 1967 [March 23, 1967], No.52460/67. Heading G2C. A light-and heat-sensitive diazo type material comprises a support coated with one or more layers containing a diazonium compound, an azo coupler, an acid stabilizer and a heat-sensitive N 2 N- disubstituted biuret of formula in which R 1 and R 2 are alkyl, cycloalkyl, aralkyl or aryl or together complete a heterocyclic ring. The biuret and optionally the coupler may be located in a first layer on the support and overcoated with a light-sensitive layer or, if the support is porous, the biuret may be coated in a layer on the back of the support. Alternatively, the biuret layer may be coated over the light-sensitive layer. The heat-sensitive layer preferably contains a polymeric binder and a pigment e.g. silicon or titanium dioxide, aluminium silicate or barium sulphate. The material may be imagewise exposed to light and developed by heat or be imagewise exposed to heat and fixed by uniform exposure to light to produce an azo dye image. |
