GB957838A - Diazotype materials - Google Patents

Abstract

957,838. Diazotype materials. CHEMISCHE FABRIEK L. VAN DER GRINTEN N.V. Sept. 12, 1960 [Sept. 17, 1959], No. 7090/63. Divided out of 957,836. Heading G2C. Transparent diazotype material comprises a transparent support provided with a hydrophilic film layer of a hydrolysed cellulose ester or hydrolysed polyvinyl ester sensitised with a diazo compound where X is an anion, Y is Cl or Br and Z is dibenzylamino or N-ethyl or methyl-N-cyclohexyl- or benzyl-amino. Specified transparent supports are transparent paper or linen and synthetic resin film. Specified optional ingredients of the sensitised layer are acids, stabilizers, e.g. sodium salt of naphthalene 1, 3, 6 tri-sulphonic acid, and reducing agents e.g. thiourea. In Examples I and II surface hydrolysed cellulose acetate on transparent paper is sensitised with a solution of (I) 17. 7g 4-N, N- dibenzylamino-3-chloro-benzene diazonium chloride zinc chloride double salt and 5 g citric acid in a litre of 34% aqueous ethanol (I) and (II) 35 g. 4- (N-methyl-N-cyclohexylamino)-3-chloro-benzene diazonium chloride, 5g. tartaric acid and 30g. sodium naphthalene 1, 3, 6 trisulphonate in a litre of 24% aqueous ethanol. In Example III transparent paper is coated with a hydrophobic layer of cellulose nitrate and overcoated with a hydrophilic layer of 63% hydrolysed cellulose triacetate which is sensitised with a solution of 33g. 4-(N-methyl- N-benzylamino)-3-chlorobenzene diazonium chloride zinc chloride double salt, 6g. citric acid and 10g. sodium benzene-1, 3-disulphonate in a litre of 24% aqueous ethanol. The materials give translucent copies of which the image has a high absorp tion for ultraviolet radiation and which are suitable for intermediate originals for the production of further diazotype copies. They are particularly suitable for processing as described in Specification 957, 836 but may also be used under other processing conditions. Specifications 698, 040, 712, 606 and 726, 755 also are referred to.