Absorbent structure for absorbent articles
Absorbent structures for diapers are provided, comprising, immobilized onto a supporting sheet, an absorbent layer with absorbent material containing superabsorbent polymer particles and therein, in the front region, a first and a second substantially longitudinal channel, each being free of said superabsorbent polymeric particles, for improved fit and/or performance throughout the use thereof.
1. An absorbent structure for an absorbent article, comprising a longitudinal axis, a supporting sheet and an absorbent layer of absorbent material, comprising a superabsorbent polymer material and a cellulosic material, said absorbent layer being supported by and immobilized on said supporting sheet; and said absorbent layer having a transverse dimension and an average width W, a longitudinal dimension and average length L, and a height dimension;
and said absorbent layer having a first longitudinally extending side portion on one side of said longitudinal axis and a second longitudinally extending side portions on the other side of the longitudinal axis; and said absorbent layer having a front region, back region and therein between a crotch region, each arranged sequentially in said longitudinal dimension;
wherein said absorbent layer has at least a first continuous, substantially longitudinally extending channel and a second continuous, substantially longitudinally extending channel that are substantially free of said superabsorbent polymer material and extending through the height of said absorbent layer, said first channel being present in said first side portion's front region only and said second channel being present in said second side portion's front region only, and each channel having an average width W′ that is least about 4% of the average width W of said absorbent layer and an average length L′ that is up to 25% of the average length L of said absorbent layer and at least 10 mm; and
wherein said supporting sheet folds into said first and second channels.
2. The absorbent structure of claim 1 , wherein said absorbent layer has longitudinal side edges and a transverse front edge and a transverse back edge, and said channels do not extend up to any of the longitudinal side edges or a transverse front edge of said absorbent layer.
3. The absorbent structure of claim 1 , wherein said W′ is from about 7% to about 25% of W.
4. The absorbent structure of claim 1 , wherein said absorbent layer comprises one or more further channels that are substantially free of superabsorbent polymer material, extending substantially in the longitudinal dimension, each further channel having an average width W″ of at least about 4% W.
5. The absorbent structure of claim 4 , wherein said one or more further channels are present in at least the crotch region of said absorbent layer.
6. The absorbent structure of claim 1 , further comprising one or more adhesive materials to immobilize said absorbent material onto said supporting sheet.
7. The absorbent structure of claim 6 , wherein said one or more adhesive materials includes a first adhesive material that is applied to said absorbent layer or part thereof once supported by said supporting sheet, said adhesive being a thermoplastic fibrous adhesive material.
8. The absorbent structure of claim 6 , wherein said one or more adhesive material include a second adhesive material present between said supporting sheet and said absorbent layer.
9. The absorbent structure of claim 1 , wherein said absorbent material consists substantially of said superabsorbent polymer material, being in the form of particles.
10. The absorbent structure of claim 1 , further comprising a material present adjacent said absorbent layer, selected from the group consisting of: i) a further supporting sheet, ii) an acquisition material layer; iii) a second absorbent structure, comprising a second supporting sheet and a second absorbent layer, wherein said second absorbent layer and said absorbent layer of the first structure are sandwiched between said supporting sheet of the first structure and said second supporting sheet.
11. The absorbent structure of claim 10 , comprising the second absorbent structure, wherein the second absorbent structure comprises channels and wherein said channels of said second absorbent structure are substantially identical to said channels of said first absorbent structure and substantially completely overlapping therewith.
12. The absorbent structure of claim 10 , comprising the second absorbent structure, wherein said supporting sheet of the first structure and/ or said second supporting sheet folds into said channels, or part thereof, and wherein one or both said supporting sheets comprise an adhesive material and wherein said supporting sheets are adhered to one another or to said absorbent layer in said channels by pressure bonding or by an adhesive material.
13. The absorbent structure of claim 10 , wherein a pressure is applied selectively to the supporting sheet material portion that correspond to said channels, to further fold said supporting sheet into said channels, wherein said absorbent layer and/ or said supporting sheet comprising one or more adhesive material and said pressure aids to bond said supporting sheet into said channels.
14. The absorbent structure of claim 1 , the absorbent article preferably being a diaper.