| 摘要 |
<p>1,228,325. Bonded non-wovens. KENDALL CO. 16 Oct., 1969 [25 Nov., 1968; 9 June, 1969], No. 50907/69. Heading D1R. A bonded nonwoven fabric is prepared by applying to the surface of an unbonded or weakly bonded fibrous web 10 of textile length fibres e.g. rayon or continuous filaments of e.g. polypropylene an aqueous dispersion of a polymer binder 18 containing in suspension ultra-short fibres of length between 50 and 300 microns e.g. wood pulp from a flooder box 16. The polymeric binder may be a polyacrylic binder, polyvinyl resin or butadienestyrene polymer. The web 10 is advanced to a suction box 29 and then passed to screen 26 where it is dried by I.R. heaters 32 to set the binder. The layer of ultra-short fibres 44 are disposed substantially horizontally and penetrate into the web but are more highly concentrated at or near the surface of the web. Alternatively an aqueous suspension of the ultra short fibres may be applied to the unbonded web and a dispersion of a polymeric binder subsequently applied. Successive applications of ultra-short fibres suspended in binder dispersion may be applied wherein the fibres in the initial application are shorter than in subsequent application. In a further embodiment, the ultra-short fibres may be coated with a polymeric binder and applied to the unbonded web from an aqueous suspension and the web subjected to treatment with the same or different binder.</p> |
