Light sensitive emulsion

Photoprocessing operations involve the developing of images in a light-sensitive emulsion that has been coated onto paper, plastic film, or a glass base. This emulsion is generally composed of silver halide salts. 

The printing surface (plate, cylinder, screen, etc.) is coated with a light sensitive emulsion and light is passed through the negative (or positive) on to this emulsion. Multiple images may be produced and accurately positioned on the printing surface by the step and repeat technique. 

Finally we address the emulsion layers that contain light-sensitive silver halide. Some of these other layers, as discussed above, contain particulates such as matte beads in overcoats, nanoparticulate semiconductors in antistat layers, copolymeric latexes in subbing layers, etc. Such layers are intrinsically composite multiphase layers, and this is also the case for the light-sensitive emulsion layers. In addition to microcrystals or nanocrystals of silver halide, present to capture light and to form developable... 

In the photographic sector, PEGs are suitable for the following products light-sensitive emulsions, photographic papers, developers, fixing, and stop baths. 

Photographic base paper. A suitable base paper for the production of photographic paper is a moisture resistant, dimensionally stable, chemically neutral chemical pulp paper that is free from traces of iron or copper. Today, papers coated with a thin polyethylene foil on both sides have replaced barite paper. This paper is used for the uptake of light-sensitive emulsions. 

In this way the exudation of the optical brightening agent from the surface of the poly(olefin) is prevented. In addition, a second corona discharge immediately prior to coating light-sensitive emulsion layer is necessary. 

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