| 摘要 |
PROBLEM TO BE SOLVED: To improve the durability and contamination resistance of a projecting screen which has high luminance and excellent diffusion performance and affords videos having high image quality by providing a plastic base material sheet with a coating film of a coating material contg. powder of calcite. SOLUTION: The sheet 1 of the transparent plastic is used as the base material sheet and the sheet 1 is provided with the coating film 2 of the coating material contg. the powder 3 of the calcite. In such a case, the arbitrary plastic sheet 1 is used for the base material sheet and the sheet having the excellent solvent resistance and dimensional stability is more preferable. The sheets formed of polyester, such as triacetyl cellulose, polyethylene terephthalate and polyethylene naphthalate, are the representative examples thereof. The coating material having the powder 3 of the calcite consists of a suitable vehicle, such as melamine resin and urethane resin, and a suitable solvent meeting the vehicle. Further, the powder 3 of the calcite has adequately a grain size of 2 to 20μm and the grain size distribution thereof is preferably as narrow as possible.
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