Film sensitized with the aid of a compound diazo and method of this layer preparation of

摘要

524,786. Diazotype sensitive materials. NAAMLOOZE VENNOOTSCHAP PHILIPS' CLOEILAMPENFABRIEKEN. Feb. 7, 1939, No. 4053. Convention date, Feb. 10, 1938. [Class 98 (ii)] In preparing diazotype papers &c. of the self-developing type, at least one constituent is applied to the paper &c. in the form of a powder suspended in a binder dissolved in a volatile liquid in which none of the constituents is soluble, and the liquid is then volatilized. The refractive index of the binder is approximately that of the constituent which most diffuses the light. Suitable binders are polystyrene, polyacrylic acid esters, resins such as dammar and mastic, and beeswax or beeswax and paraffin. As solvents chlorinated hydrocarbons such as carbon tetrachloride and ethylene chloride may be used. A material which absorbs moisture, e.g. dried starch, or one yielding a difficultly soluble hydrated oxide with alkali, e.g. aluminium sulphate, may be included in the layer. In an example, anhydrous soda or quicklime, dye components such as phloroglucinol, resorcinol, or R-salt, aluminium sulphate talc or wheat flour are mixed in a ball mill with ground polystyrene, the mixture is dispersed in carbon tetrachloride, and the dispersion is applied to a carrier, as with a roller.