| 摘要 |
<p>PURPOSE:To improve the accuracy of thickness of the circumferential part of a laminated sheet thereby minimizing the width of the trimming so as to increase the yield of the laminated sheet, by using mirror plates, the thickness of the circumferential part of each of which is gradually reduced toward the edges. CONSTITUTION:A prepreg 8 that has been obtained by impregnating a base material with a thermosetting resin varnish is sandwiched between the mirror plates, the circumferential part of each of which is thinner than the remaining part and is gradually tapered outwardly. An example of such a mirror plate is a square plate of stainless steel having a thickness of 2.5mm. with the length of the side being 1,060mm. whose circumferential part extending 30mm. is tapered finally to be 2.3mm. in thickness. Then the prepreg and the mirror plates are heated under pressure to mold the prepreg to obtain a laminated sheet. Accodingly the accuracy of the thickness of the circumferential part of the laminated sheet can be improved, and the width of the trimming to obtain a laminated sheet whose thickness is in the range of a prescribed tolerance can be minimized so that the yield of the laminated sheet can be increased.</p> |
