Patent ID: 9169586
Filing Date: 2015-10-27
Classification: A61F,D04H

Abstract:
1. A process for preparing an absorbent topsheet layer having a density which varies in the transverse direction for reduced transverse capillarity, the absorbent topsheet layer configured for a cotton-based sanitary towel with wings for physiological liquids, said process comprising: (a) a first hydroentangling of a pre-needled or pre-punched layer of fibres with pressures between 30 and 60 bars, with jets of water adjacent one to the other, in order to obtain a light cohesion between the fibres resulting in a lightly hydroentangled pad; and (b) a second hydroentangling of the lightly hydroentangled pad obtained from step (a), using pressures higher than or equal to 100 bars, said jets being distanced one from the other with a pitch of at least 0.5 mm; wherein said topsheet layer consists of a nonwoven form of natural fibres of cotton or a mixture thereof with polylactic acid and/or viscose, and said process provides the topsheet layer with a first plurality of longitudinal straight lines with a form of grooves having a density of fibres of at least 5% greater than a second plurality of longitudinal straight lines, each alternated with each longitudinal line, said lines with lower density representing longitudinal channelings for the liquid along which the liquid can expand, the lines with greater density constituting a barrier to the passage of the liquid in the transverse direction with respect to said longitudinal lines, and said first plurality of longitudinal lines of higher density of fibres having a smaller thickness with respect to the thickness of said second plurality of longitudinal lines.