As a professional color booklet printing services supplier, Image Printing Packaging Limited has the advantages of high quality, aggressive prices and prompt delivery. We are devoted to offering our professional color booklet printing services for overseas customers. Not only color booklet printing services do we provide, we also specialize in various book printing, bible printing, notebook printing and calendar printing services too.
For the brilliant enamel now often generally applied to fine cards and other purposes of color booklet printing, the following formula is given. For white and for all pale and delicate shades, take twenty-four parts, by weight, of paraffine; add thereto 100 parts of pure kaolin (China clay), very dry and reduced to a fine powder. Before mixing with the kaolin, the paraffine must be heated to fusing point. Let the mixture cool, and it will form a homogeneous mass, which is to be reduced to powder, and worked into paste in a paint-mill, with warm water. This is the enamel ready for application. It can be tinted according to fancy. The metal plate, of copper or zinc, is coated with a very thin layer color booklet printing, and when this coat has become perfectly dry, a film of bichromatized albumen is flowed over the plate. It is next exposed in the camera, and afterwards washed with water, in order to dissolve all the albumen which has not been rendered insoluble by the luminous action; it is then treated with spirit of turpentine, which dissolves all those parts of the layer of bitumen that have become exposed. The plate can now be attacked directly by water acidulated with from four to six per cent of nitric acid. The great advantage of this method consists in the high sensitiveness of the bichromatized albumen, at the same time preserving the solid reserve produced by the bitumen of a metallic surface. When a pen has become so corroded as to be useless, it can be made good as new by holding it in the flame of a gas jet for half a minute; then drop in cold water, take out, wipe clean, and it will be ready for use color booklet printing.
To produce electrotypes or stereotypes of letters, signatures, ordinary written matter, drawings or sketches, coat a smooth surface of glass or metal with a smooth, thin layer of gelatine, and let it dry. Then write or draw upon it with an ink containing chrome alum, allow it to dry exposed to light, and immerse the plate in water for color booklet printing jobs. Those parts of the surface which have not been written upon will swell up and form a relief plate, while those parts which have been written upon with the chrome ink have become insoluble in water, after exposure to light. The relief may be transferred to plaster of Paris, and from this may be made a plate in type metal.
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