Matte beads

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... 

Adhesive forces and attractive interactions are greatest for parallel planar surfaces and decrease in proportion to the contact area. Matte beads in the 1 to 5 pm diameter range, when coated at a low-number density in overcoat layers, mechanically retard adhesion interactions between stacked layers (as in a box of sheet film or paper) and rolled layers (as in large rolls during manufacturing or in consumer roll film), since only point contacts can be made with a surface coming in contact with an overcoat layer containing matte beads. 

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