| 摘要 |
<p>1,187,503. Laminated stencil blanks. KONTOR KEMI A.S. 4 July, 1967 [11 July, 1966], No. 30647/67. Heading B5N. A stencil blank for perforation by electrical sparks comprises a backing sheet and a stencil sheet which is of inherently electrically conductive synthetic resin or which has at least one layer of such material. Suitable synthetic resins are polyolefins such as polyisobutylene, which have been subjected to bombardment by electrons; polyamides subjected to vacuum pyrolysis at 850‹ C.; and polymers treated with tetracyano-quino-di-methane. The stencil sheet may be formed of two bonded resin layers with different conductivities, or of a thin paper sheet containing finely dispersed carbon particles coated with the resin. The backing sheet is of conductive paper or of paper with conductive coating.</p> |
