| 摘要 |
PROBLEM TO BE SOLVED: To provide a manufacturing method for an optical sheet consisting of a thermoplastic resin containing a crystalline resin which can maintain the amorphous state of the resin sheet while obtaining a high transfer precision of an embossing shape. SOLUTION: This manufacturing method is used for manufacturing the optical sheet consisting of the transparent crystalline resin sheet under the amorphous state the front surface of which undergoes an embossing process. In the manufacturing method, an embossing belt 13 made of a metal the surface of which has the embossing shape is wound around a heating roll 11 and a cooling roll 12, and the embossing process is applied to the resin sheet 10 at a temperature of the glass transition temperature or higher on the embossing belt 13. Then, the resin sheet 10 is peeled from the embossing belt 13 by rapidly cooling the resin sheet 10 to a temperature being lower than the glass transition temperature. Thus, the whitening of the resin sheet 10 by the excessive crystallization can be prevented from occurring even when the resin sheet 10 is made of crystalline resins while maintaining the shape transferability to the resin sheet 10. COPYRIGHT: (C)2009,JPO&INPIT |
