Absorbent sheet of variable local base weight with a band prepared with a perforated polymeric band

摘要

A method for manufacturing an absorbent cellulosic sheet corresponding to strip (10), the method comprises: (A) compactly dehydrating a paper pulp for papermaking in order to form a nascent weft (154) having a seemingly random distribution of fiber orientation for papermaking; (B) apply the nascent weft (154) to a transfer surface (358) that moves at a superficial transfer rate; (C) match the nascent weft (154) from the transfer surface (358) to a consistency of 30% to 60% characterized in that it uses a generally flat polymeric accordion band (50) provided with perforations through the band, wherein the acording stage occurs under pressure at a nip of the band (174) defined between the transfer surface (358) and the accordion band (50), the band (50) moves at a speed of band that is slower than the superficial transfer speed; and where the geometry of the band, the parameters of the nip, the delta velocity and the consistency of the band are selected such that the band (154) corresponds to the transfer surface (358) and is redistributed in the corresponding band (50) to form the weft (154) wet in the web, the weft (154) having wet: (a) fiber-enriched regions of a relatively high local basis weight, including fiber-enriched regions: (i) convex parts hollow, and (ii) crested fiber enriched parts adjacent to the convex parts, each part enriched with crested fiber, an inclination of the fiber orientation in the transverse direction of the machine (CD), the fiber enriched parts being interconnected ridges with (b) connection regions of a relatively low local basis weight; (D) apply vacuum to the accordion band (50) while the wet weft (154) is retained in the band to expand the wet weft (154) and melt the convex parts and the crested fiber enriched parts; and (E) drying the wet weft (154) to form the absorbent cellulosic sheet (10), wherein the papermaking pulp is selected and the steps of band matching, vacuum application and drying are controlled so such that the sheet (10) has: (a) hollow convex regions enriched with fiber (12) on an upper side of the sheet (10), the convex regions having a relatively high local basis weight, (b) connection regions ( 18) forming a network that interconnects the convex regions (12), the connection regions having a relatively low local basis weight; and (c) transition areas (38) with consolidated fibers that undergo transition from the connection regions (18) to the convex regions (12).