| 摘要 |
<p>717,022. Printing surfaces. TRAVIS, R. A. Nov. 26, 1952 [Dec. 5, 1951 ; Feb. 20, 1952], No. 29937/52. Class 100 (2). [Also in Group VIII] Stereotype flongs.-A flong consists of a smooth-surfaced fibrous sheet comprised of a mixture of short water-absorbent fibres, and long non-absorbent fibres of high tensile strength, the water-absorbent fibres constituting the major proportion of the sheet and serving to make the sheet water-absorbent and impressible, while the non-absorbent fibres serve to make the sheet dimensionally stable when its moisture content varies. The water absorbent fibre may be comprised of cellulose and the long non-absorbent fibre of glass fi'ament of a diameter between .00002 and 0004 inches. The length of the cellulose and glass fibres is approximately 0.080- 0.120 inches and about 0.5 inches respectively, the glass fibre content being from 20 to 50 per cent of the sheet by weight. The flong also includes a clay fibre amounting to between 5 and 20 per cent of the sheet by weight. The flong is prepared by beating a pulp of cellulose fibres, adding to the pulp the glass fibres, mixing the glass fibres with the pulp so as not to crush, break, or otherwise shorten the glass fibres, matting the cellulose and glass fibres together, and withdrawing the surplus water of the pulp. The sheet is col'ected, built up to the required thickness, and given a smooth facing consisting of china clay talc or ground mica and an adhesive such as dextrin or starch.</p> |
