GB686686A - Photographic diazotype material and methods for preparing the same - Google Patents

Abstract

686,686. Photographic diazotype material. ASSOCIATED DRAWING MATERIALS & EQUIPMENT, Ltd. Jan. 10, 1951 [Jan. 10, 1950], No. 650/50. Class 98 (ii). A photographic diazotype print has selected areas coated with different diazotype preparations and/or with different colouring materials. The support may be of paper, cloth, card, or film and may be different coloured in selected areas by applying the colouring by rollers, brushing, spraying with or without a mask, or by printing, using a very open screen when the colour is in the form of greasy ink. In an example of this procedure, a sheet of paper is coloured yellow on the left-hand side by a roller dipping into an aqueous or alcoholic solution of Auramine O, red along a central line by a disc-like roller dipping into an aqueous or alcoholic solution of Rhodamine 6GB, and blue on the right-hand side by a roller dipping into an aqueous or alcoholic solution of Victoria Blue B. After drying, the paper is coated with a light-sensitive diazotype solution, and again dried. The rollers may be plain or embossed, and the diazotype solution may be applied first. The support may, alternatively, be coated in selected areas with different diazotype solutions. In an example of this procedure, the left-hand side of the paper is coated with an acidified solution of the zinc chloride double salt of diazotized 1-N-ethyl : N-benzylamino-4- aminobenzene, and the right-hand side with an acidified solution of the zinc chloride double salt of diazotized 1 - N : N - diethylamino - 2- chloro-4-aminobenzene. The exposed paper is developed in an alkaline solution of phloroglucinol to give black markings on the lefthand side and red-brown markings on the right-hand side.