| 摘要 |
A wet-laid non-woven fabric web having the hand and drape of a woven fabric-for use as a filter, table napkin, towelling bandage, bookbinding &c. is formed in a paper-making machine by depositing an aqueous dispersion of fibres on a screen assembly which comprises a base screen member-for example of Fourdrinier wire - having superimposed thereon a moulding screen member of coarser mesh so that the web has a greater fibre concentration between the elements of the moulding screen member than thereon. The coarser screen member may be a woven screen having less than a 1/10th and preferably less than 1/50th of the number of apertures in the fine mesh screen, and may have solid discs secured to the member to block off selected areas of the screen so that the formed web has circular portions of low fibre concentration (Fig. 14, not shown). The coarser screen member may also be corrugated or have protrusions to form a corrugated or creped web. The crepe may be of over 100% and be in the machine and/or cross-machine directions. A Four-drinier, rotoformer, or cylinder machine may be used. The fibres in the slurry should be well dispersed by having a concentration of substantially less than 5% or by using a dispersing agent. The strength of the web may be increased by treatment with latex, polyvinyl chloride or cationic agents, or by a post-formation treatment-such as spot welding. Fibres of hemp, casoa jute, kraft, rayon, nylon, polyester or vinyl copolymers may be used.
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