GB454137A - Improvements in or relating to diazo type printing - Google Patents

Abstract

454,137. Photographic diazotype processes. WATERMAN, H. I., 63, Nieuwe Plantage, Delft, and BORGESIUS, T. W. A., 87, Nieuwe Bossche Weg, Tilburg, both in Holland. March 20, 1936, No. 8428. [Class 98 (ii)] A light or heat sensitive layer comprises casein or casein containing products such as skimmed milk, diazotized before, during or after production of the layer. The layer may be applied on a paper, glass, cellulose or nitrocellulose base or on fabrics, such as mercerized cotton or cotton treated with cuprammonium solution. Fabrics may be impregnated with a solution of the caseincontaining material. Binding media such as gelatine, agar-agar, and carragheen moss, and plasticizers such as phenol, tricresylphosphate and butylphosphate may be added, and the layer may be hardened with formalin or alum. The layer may be attached to the base by adhesives such as collodion. The casein may be dissolved in ammonia, borax, waterglass or sodium phosphate in the production of the layer. Exposure to light is effected under a negative or stencil, or images may be produced with heated stamps or rolls. The diazotized product is coupled with #- naphthol, Schaffers' acid, H-acid, M-acid, R-acid, S-acid, Cleve's acids, resorcinol, aniline, aminophenols, phenylpyrazolone derivatives or arylamides of acetylacetic acid. The image may be after-treated with potassium dichromate or copper sulphate.