BELT-CREPED MULTILAYER SHEET WITH VARIABLE LOCAL BASIC WEIGHT WITH CELLULOSE MICROFIBRE OBTAINED BY MEANS OF PERFORATED POLYMER TAPE Russian patent published in 2017 - IPC D21H21/14 D21H25/00 

FIELD: pulp and paper industry.

SUBSTANCE: invention relates to multilayer absorbing sheet, containing cellulose fibre, suitable for paper towels and napkins. Product in form of multilayer napkin or multilayer towel comprises at least one web obtained by wet laying, produced by belt creping method, wherein at least one web obtained by wet laying contains from 20 to 60 WT% of fibrillated regenerated cellulose microfibres and from 40 to 80 WT% of paper forming fibres originating from wood pulp, wherein said, at least, one web obtained by wet laying has following formed in it: (i) plurality of enriched with fibres hollow dome-shaped areas, projecting from upper side of, at least, one web obtained by wet laying, wherein hollow dome-shaped areas have side wall, formed along, at least, their front edge, wherein side wall has local basic weight, which exceeds average basic weight of, at least, one web obtained by wet laying; (ii) connecting network forming areas, connecting hollow dome-shaped areas of, at least, one web obtained by wet laying, wherein connecting areas have local basic weight, which is much lower, than hollow dome-shaped areas local basic weight; and (iii) transition areas with consolidated fibrous areas, which transfer from connecting areas to hollow dome-shaped areas, extending upward and inside from connecting areas to hollow dome-shaped areas side walls. Multilayer absorbing sheet comprises, at least, first and second layers, connected together. In one design provided are first and second layers with originating from pulp paper forming fibres and fibrillated regenerated cellulose microfibres, having CSF value of less than 175 ml; wherein sheet has thickness of 180–250 mil/8 sheets and shows wiping dry time of less than 20 s, SAT capacity in range of 350–500 g/m², SAT rate in range of 0.05–0.25 g/s^0.5, wet elongation CD in range of 400–2,500 g/3" and CD-tensile strength ratio in wet state/in dry state from 35 to 60 %. Multilayer sheets have sufficient absorbing capacity for use as conventional paper towels.

EFFECT: preferred products have differential pores volume for pores with diameter of less than 5 mqm, making, at least, 75 mm³/g/mqm.

76 cl, 42 dwg, 12 tbl