GB1193987A - Heat-Developable Diazotype Material - Google Patents

Abstract

1,193,987. Photographic diazotype materials. VAN DER GRINTEN N.V. Nov. 21, 1967 [Dec. 2, 1966], No. 52981/67. Heading G2C. A heat-developable, diazotype material comprises a support coated with a diazonium compound, an acid or acid salt, a water-soluble hydrophilic binder, an azo-coupler of formular R 1 -CH 2 -CO-R 2 wherein R 1 is an acyl group and R 2 is an amine residue derived from a primary amine having a molecular weight of at least 150, a melting point above 50‹ C. and a solubity in water less than 1x10<SP>-3</SP> mol/litre, and a material generating alkali on heating above 100‹ C. and having a solubility in water less than 2 grams per litre, the coupler and alkali-generater being in the form of dispersed particles of average size between 0À1 and 10. The ingredients may be in one or two layers; the alkali generator and/or coupler being dispersed in the lower layer. The material may also contain another coupler such as a dihydroxymaphthalene so that a black image is formed on development. The sensitive materials are preferably those of Specifications 1,115,496, and 1,066,105. In the examples, a dispersion of the coupler in polyvinyl alcohol and polyvinyl pyrrolidone is prepared and either directly coated on a support or admixed with a dispersion containing the heat-sensitive material and coated on a support or admixed with a dispersion containing all other ingredients and silica and coated on the support. If two layers are used, the top layer contains the diazonium compound, acid and hydrophilic binder. Specified couplers are N-acetoacet-4-benzoylamino-dialkoxyanilines, N-acetoacet-trihtalo-or bezoyl-anilines, N-acetoacet-octa-or hexa-decylamine, and N,N<SP>1</SP> -bis (acetoacet) decane-or dodecane-diamines.