GB367480A - Improved process of printing in colours - Google Patents

Abstract

367,480. Ink. CAVE, R. G., 22, St. Phillip's Road, Dalston, London. Dec. 2, 1930, No. 36314. [Class 146 (iii).] In a process for producing multicolour prints by successively printing superimposed monochromatic component pictures through fine screens of silk or wire gauze treated with a filling material to render them impermeable to ink except at the parts corresponding with the monochromatic picture to be printed by means of the screens, the inks employed consist of aqueous solutions of dyestuffs thickened with a water-soluble thickening agent, this resulting in more rapid dryings. The thickener must be such as not to prevent the admixture of the dyestuffs in the different inks to produce composite colours, and may consist of gum tragacanth, wheat or other starch, or a mixture of these substances, the proportion varying with the agent employed and the viscosity desired. For the purpose of assisting in the solution of dyestuffs whose solubility in water is insufficient to produce the required depth of colour, the solutions may contain an organic solvent such as alcohol which is miscible with water, and is sufficiently volatile not to interfere with the rate of drying.