GB554300A - Improvements in sensitive photographic materials - Google Patents

Abstract

554,300. Sensitive photographic materials. KODAK, Ltd., BATLEY, A., SOPER, A. K., and BLABER, M. P. W. (Eastman Kodak Co., Wynd, C. L. A., and Lane, G.T.). Sept. 10, 1941, Nos. 7152/43, 7153/43 (both divided out of 554,292), and 7158/43 (divided out of 557,109). [Class 98 (ii)] A metal or other support is sensitized by transferring thereto a sensitive emulsion layer stripped from another support. A latent image may be formed in the emulsion layer before or after stripping. A sensitive silver salt emulsion layer temporarily held on another support may be caused to adhere on its outermost side to the metal or other support by means of an adhesive layer first coated on the metal or other support and the temporary support is simultaneously or subsequently dry-stripped off. Alternatively, the adhesive layer may be coated on the outermost side of the emulsion layer. The temporary support may be left as a protective layer until the material is required for use. The adhesive layer may be a layer which can be rendered adhesive by heat or by treatment with a softener. A varnish layer may be applied to the sensitive side of the stripping material before it is caused to adhere to the metal by the adhesive layer. Adhesive layers may be coated both on the emulsion and on the metal. Supports other than metal are concrete, hard sheets of plastics, and tracing cloth. In an example, paper is coated with a solution of beeswax in trichlorethylene, then with a process-type emulsion, and then with a lacquer prepared by dissolving a mixture of cellulose nitrate, ester gum, dibutyl phthalate, and formamide in a mixed solvent comprising acetone, butyl acetate, butyl alcohol, and amyl acetate. The metal support may comprise anodized polished aluminium coated with a lacquer prepared by dissolving a mixture of cellulose nitrate, ester gum and dibutyl phthalate in a mixed solvent comprising ethyl acetate and n-butyl acetate. Before use, a softener solution comprising industrial spirit and the mono-methyl ether of ethylene glycol is applied to either or both lacquer surfaces, and the two are pressed into contact. After curing for 24 hours, the paper is stripped off. For photolithography, the emulsion should have a low melting point, e.g. below 160‹ F. To facilitate writing on the material, a matting material may be incorporated in the surface or a matt over-coating layer may be provided. The metal sheet may be rendered non- corrosible before use by treating in a bath containing phosphoric acid or by coating with a black lacquer. With a black support, the image may be produced in a light-coloured substance, e.g. silver iodide. If a white or coloured lacquer is used, the image is produced in a black or coloured subtance. The lacquer may contain a phosphorescent or fluorescent substance for use in the method described in Specification 548,795. The temporary support may be opaque or coloured to render it absorbent of rays to which the emulsion is sensitive. Specifications 549,371, 553,341, and 555,383 also are referred to.