Patent ID: 6550380
Filing Date: 2003-04-22
Classification: B41C,B41J

Abstract:
A method for stencil plate making of a stencil sheet for stencil printing performed for a micro porous plastic sheet, comprising the steps of:providing required heat for melting a surface or inside of the plastic sheet to a form of negative image by heating means of a thermal head (TPH); thermally shrinking or heat melting micro pores in the heated area of said micro porous plastic sheet; and pressing the micro pores of the sheet for blockage wherein the following formula (1) and (2) concerning driving conditions for said thermal head; the following formula (3) concerning pressure for stencil making for pressing the micro pores; and the following formula (4) concerning thermal shrinking rate of said sheet are satisfied simultaneously, âˆ’30&lE;Tpâˆ’Tm&lE;300 (Â° C.)â€ƒâ€ƒ(1) (wherein, Tp represents heating peak temperature, and Tm represents a melting temperature (melting point) of the sheet)10&lE;ToÃ—100/Ts&lE;80 (%)â€ƒâ€ƒ(2) (wherein, To represents current-carrying time period, Ts represents current-carrying cycle, ToÃ—100/Ts represents the ratio of To to Ts)0.1&lE;p&lE;1.0 (MPa)â€ƒâ€ƒ(3) (wherein, P represents pressure for stencil plate making)1&lE;STm-30&lE;20 (%)â€ƒâ€ƒ(4) (wherein, STm-30 represents the thermal shrinkage rate at a temperature 30Â° C. lower than that of the melting point of the sheet Tm in TMA (thermal mechanical analysis).