| 摘要 |
1464783 Surface treatment of sheet material BURROUGHS CORP 19 Nov 1974 [19 Dec 1973] 49939/74 Heading B5A A sheet or piece of plastics material 72, such as a credit card, is polished or embossed by passing through the nip of heated input rollers 10 and 12 between polished belts 44 and 46 and as maintained under heat and pressure by heatresistant squeeze rollers 48 and 50 so as to soften only the surface of the sheet which then assumes the pattern or smoothness of the belt. The belt then passes in an arc through the coolant material 62 still maintained in contact with the polished belt. Pieces are discharged through rolls 30, 32 to be stacked. Squeegee members 64 and 66 remove the coolant from the belts before return to the heated rollers. The heat imparted to the plastics, the pressure of the squeeze rolls and the time the plastics take to pass through the nip of the rollers to the coolant are adjusted so as to result in polishing moulding of the surface only. |
