Absorbent core with curved channel-forming areas
A substantially planar absorbent core includes a core wrap enclosing an absorbent material that is substantially free of cellulose fibers and forms a pattern of discrete absorbent material areas. The core further comprises at least a pair of curved longitudinally-extending channel-forming areas substantially free of absorbent material, through which the top side of the core wrap is attached to the bottom side of the core wrap along a core wrap bond. Each of the longitudinally-extending channel-forming areas are longitudinally flanked internally by a first flanking absorbent material area and externally by a second flanking absorbent material area, the first and second flanking absorbent material areas following the curvature of the channel-forming area.
1. A substantially planar absorbent core comprising a core wrap enclosing an absorbent material, the absorbent core having a longitudinal axis and comprising a front region, a back region and a middle region, each region having an equal length along the longitudinal axis, wherein the absorbent material is substantially free of cellulose fibers and forms a pattern of absorbent material areas,
the core further comprising at least a pair of curved longitudinally-extending channel-forming areas substantially free of absorbent material, through each of which the top side of the core wrap is attached to the bottom side of the core wrap along a core wrap bond, so that when the absorbent material areas adjacent the channel-forming areas absorb a fluid and swells, three-dimensional channels are formed along each core wrap bond,
wherein these channel-forming areas are disposed on opposite sides of the longitudinal axis,
wherein each of said longitudinally-extending channel-forming areas are longitudinally flanked internally by a first flanking absorbent material area and externally by a second flanking absorbent material area, the first and second flanking absorbent material areas following the curvature of the channel-forming area.
2. The absorbent core of claim 1 , wherein the longitudinally-extending channel-forming areas are symmetrically disposed relative to the longitudinal axis.
3. The absorbent core of claim 1 , wherein the longitudinally-extending channel-forming areas are concave towards the longitudinal axis and are closest to each other in the middle region.
4. The absorbent core of claim 1 , further comprising a central absorbent material area at least partially contiguous with the longitudinal axis.
5. The absorbent core of claim 4 , wherein the central absorbent material area branches towards the front and/or the back of the core.
6. The absorbent core of claim 3 , wherein the central absorbent material area forms the internally longitudinally flanking area of the channel-forming areas.
7. The absorbent core of claim 1 , further comprising straight longitudinally-extending material areas.
8. The absorbent core of claim 1 , wherein the absorbent core comprises from about 2 g to about 16 g of superabsorbent polymer particles.
9. The absorbent core of claim 1 , further comprising a thermoplastic adhesive material to immobilize at least some of the absorbent material within the core wrap.
10. The absorbent core of claim 9 wherein the thermoplastic adhesive material comprises at least one selected from auxiliary glue and a micro-fibrous glue.
11. The absorbent core of claim 1 , wherein the core wrap comprises a first substrate and a second substrate and the first substrate forms substantially the whole of the top side of the core wrap and the second substrate forms substantially the whole of the bottom side of the core wrap.
12. The absorbent core of claim 11 , wherein the first substrate and the second substrate are sealed in a C-wrap configuration along their longitudinal side edges.
13. The absorbent core of claim 1 , wherein the absorbent material is macroscopically profiled in the longitudinal direction so that the basis weight of the absorbent material is higher in the middle region than in the front region and/or back region.
14. An absorbent article comprising the absorbent core of claim 1 .
15. The absorbent article of claim 14 , wherein the article is a baby diaper.