Multi-layered non-woven structure for use as a component of disposable absorbent articles
The present invention relates to multi-layered non-woven structures being useful as components of disposable absorbent articles and garments comprising super absorbent particles and thereby acts as a core. The invention thereby ensures that the body fluids can penetrate from a first layer, which acts as an acquisition layer, up to a third layer comprising SAP particles, the second non-woven layer serving to decrease the fluid volume per surface unit, as a conventional dispersion layer. However the second layer of the invention additionally acts like a non-return valve, preventing, or at least strongly limiting, any fluid transfer from the third layer to the first layer. Channels free of SAP can additionally be design to improve the inlet and rewet properties of the multilayer acquisition and distribution sheet non-woven material.
1 . A multilayer acquisition and distribution sheet nonwoven material for hygiene articles comprising at least three layers on top of each other:
a first layer for acquiring and transferring body fluids to the second layer;
a second layer for receiving the body fluids from the first layer and spreading the body fluids over the second layer, and
a third layer comprising superabsorbent polymer (SAP) particles, for receiving the body fluids from the second layer, the second layer forwarding the body fluids to the third layer irreversibly, the second layer comprising void volumes and wherein the void volumes in the second layer are smaller than the SAP particles,
wherein the second layer is arranged with the void volumes smaller than void volumes of the third layer of which the fibers are coarse fibers, whereas fibers of the second layer are finer,
wherein void volumes in the first layer are larger than the void volumes in the second layer,
wherein the SAP particles are dispersed in the third layer according to a pattern which leaves channels extending through the third layer from the second nonwoven layer, free of SAP particles, wherein the channels do not extend into the second layer or the first layer,
wherein the first layer and the second layer comprise a plurality of discrete portions, with regions between the plurality of discrete portions each defining a continuous void space, wherein the continuous void spaces are located so as to not overlap with the channels in the third layer.
2 . The multilayer acquisition and distribution sheet nonwoven material of claim 1 , wherein the fibers of the second layer have a fiber size in a range of 0.7 to 7 decitex (dtex).
3 . The multilayer acquisition and distribution sheet nonwoven material according to claim 1 , wherein:
fibers of the first layer have a first fiber size in a first range of 2 to 28 dtex;
fibers of the second layer have a second fiber size in a second range of 0.7 to 7 dtex; and
fibers of the third layer have a third fiber size in a third range of 2 to 70 dtex.
4 . The multilayer acquisition and distribution sheet nonwoven material of claim 1 , wherein the channels are free of SAP particles in a swollen state, where fluid is present in the third layer, and in a non-swollen state, where fluid is not present in the third layer.