| 摘要 |
783,002. Making paper, &c. bags. BOWATER RESEARCH & DEVELOPMENT CO., Ltd. [formerly BOWATERS DEVELOPMENT & RESEARCH, Ltd.]. March 21, 1956 [March 21, 1955], No. 8208/55. Class 94(2). [Also in Group XXVIII] Multiply bags have a barrier ply consisting of paper with a layer of impervious material such as polythene, the longitudinal seam of the barrier ply being formed by securing a separate paper strip along its abutting or overlapping edges. The other side of the strip may have a similar impervious layer. In one method of making bags in which the barrier ply is innermost, paper webs 24 and the composite web 25 are passed in transversely staggered relation through gluing means 11-13 for applying adhesive to their margins 26, and thence to tubing apparatus (details not shown). During tubing, a strip 30 of paper having an impervious layer is passed from a roll 19 through gluing means 15-17 to beneath a roller 21 which secures it to the abutting edges of the web 25. In another method, Figs. 4, 5 (not shown), the non- composite webs are assembled as before, but prior to the composite web being laid on them, the adhesive coated seam strip is secured to one of its longitudinal edges with a margin projecting for application to its other edge after tubing. |
