| 摘要 |
<p>By cold rolling a metal sheet coated with a film of polymer, the adhesion and other physical properties of the film are improved. The film serves as a lubricant for the rolling and as a protective coating for the sheet which, however, allows further working of the sheet, if desired. (The rolls may be heated or cooled during rolling for controlling the temperature of bonding). The increased adhesion is due to minute roughening of the metal surface after rolling and also to reactive sites being formed in the polymer on stressing to cause chemical bonding. Heat treatment after rolling can further increase the film adhesion. The sheet thickness is from 5-75 mils, the film thickness at least 0,2 mils thick, and the rolling temperature below 400 DEG F. Suitable metals include steel, copper, iron, aluminium and tin plate, and suitable plastics include film forming polymers and interpolymers of vinyl acetate, vinyl alcohol, vinyl chloride, vinylidene chloride, vinyl acetals, styrene, butadiene, isoprene, acrylate and methacrylate esters, acrylic and methacrylic amides, acrylonitrile, ethylene, propylene, tetrafluoroethylene and ethylene oxide. Appropriate plasticizers may be used but it is preferred to use plasticizer-free systems. The film may be formed by doctoring on of plastisols or emulsions, rolling or spraying on of solutions, extruding or calendering of melts or of plastics softened with volatile solvents, or pressing on of preferred films.</p> |
