Absorbent core for disposable absorbent articles with increased absorption rate and improved integrity
The present disclosure invention relates to a disposable absorbent article ( 100 ) comprising a liquid-pervious topsheet ( 10 ), a liquid-impervious backsheet ( 20 ) and an absorbent assembly ( 30 ) between the topsheet ( 10 ) and the backsheet ( 20 ). The absorbent assembly ( 30 ) comprises an absorbent core ( 40 ), an upper core wrap ( 50 ) and a lower core wrap ( 60 ). The absorbent core ( 40 ) comprises at least two cavities ( 70 ) free of absorbent material wherein the upper core wrap ( 50 ) and the lower core wrap ( 60 ) are permanently attached to each other, said cavities ( 70 ) being interconnected via at least one connecting line ( 80 ) comprising absorbent material. The absorbent core ( 40 ) has a first basis weight in the zone out of the cavities ( 70 ) and the connecting lines ( 80 ) and a second basis weight in the connecting lines ( 80 ), the first basis weight being greater than the second basis weight. in the cavities ( 70 ). The resulting absorbent assembly ( 30 ) may show all together a very good integrity, a very good distribution of fluids and a quick rate of absorption.
1. A disposable absorbent article ( 100 ) having a longitudinal direction and a transverse direction, the absorbent article comprising:
a liquid-pervious topsheet ( 10 ),
a liquid-impervious backsheet ( 20 ) and
an absorbent assembly ( 30 ) disposed between the topsheet ( 10 ) and the backsheet ( 20 ) and having two longitudinal edges ( 41 , 41 ′), two transverse edges ( 42 , 42 ′), a wearer-facing surface ( 43 ), a garment-facing surface ( 44 ), a longitudinal central axis (Y-Y) extending along a length of the absorbent assembly ( 30 ) and a transverse central axis (X-X) defining a front portion ( 45 ) and a back portion ( 46 ), the absorbent assembly ( 30 ) comprising:
an absorbent core ( 40 ),
an upper core wrap ( 50 ) and
a lower core wrap ( 60 ),
wherein the absorbent core ( 40 ) comprises absorbent material comprised by a mixture of superabsorbent polymer and cellulosic fibers,
wherein the absorbent core ( 40 ) comprises at least two cavities ( 70 ) free of absorbent material having a width (W 1 ) with respect to the transverse central axis (X-X) and a length (L 1 ) with respect to the longitudinal central axis (Y-Y), said cavities ( 70 ) being interconnected via at least one connecting line ( 80 ) having a width (W 2 ) with respect to the transverse central axis (X-X) and a length (L 2 ) with respect to the longitudinal central axis (Y-Y), the at least one connecting line ( 80 ) comprising absorbent material,
wherein the absorbent core ( 40 ) has a first basis weight (bw 1 ) in the zone out of the cavities ( 70 ) and the connecting lines ( 80 ), and a second basis weight (bw 2 ) in the connecting lines, the first basis weight (bw 1 ) being greater than the second basis weight (bw 2 ), and wherein the upper core wrap ( 50 ) and the lower core wrap ( 60 ) are permanently attached to each other in the cavities ( 70 ).
2. The disposable absorbent article ( 100 ) according to claim 1 , wherein the at least two cavities ( 70 ) are aligned on the longitudinal central axis (Y-Y) of the absorbent assembly ( 30 ) and interconnected via at least one longitudinal connecting line ( 80 ) substantially parallel to the longitudinal central axis (Y-Y).
3. The disposable absorbent article ( 100 ) according to claim 1 , wherein the cavities ( 70 ) form a pattern, the pattern comprising two rows of at least two cavities ( 70 ), the cavities ( 70 ) of each row being longitudinally interconnected via at least one longitudinal connecting line ( 80 ) substantially parallel to the longitudinal central axis (Y-Y), each row being disposed on each side of the longitudinal central axis (Y-Y).
4. The disposable absorbent article ( 100 ) according to claim 1 , wherein the cavities ( 70 ) are longitudinally spaced from each other by a distance between 5 mm and 250 mm and are transversely spaced from each other by a distance between 5 mm and 250 mm.
5. The disposable absorbent article ( 100 ) according to claim 1 , wherein the cavities ( 70 ) have a shape selected from the group consisting of triangles, squares, rectangles, polygons, circles, ovals, semi-circles, arrow-shapes, crosses, irregular shapes and combinations thereof.
6. The disposable absorbent article ( 100 ) according to claim 1 , wherein the cavities ( 70 ) have an area between 50 mm 2 and 2500 mm 2 .
7. The disposable absorbent article according to claim 1 , wherein more than 50% of the total area of the cavities ( 70 ) is disposed in the front portion ( 45 ) of the absorbent assembly ( 30 ).
8. The disposable absorbent article according to claim 1 , wherein the ratio (W 2 /W 1 ) between the transverse width (W 2 ) of the at least one connecting line and the transverse width (W 1 ) of the cavities ( 70 ) is at most 1.
9. The disposable absorbent article according to claim 1 , wherein the ratio (bw 2 /bw 1 ) between the second basis weight (bw 2 ) and the first basis weight (bw 1 ) is between 0.25 and 0.95.
10. The disposable absorbent article according to claim 1 , wherein the upper core wrap ( 50 ) is permanently attached to the lower core wrap ( 60 ) in the cavities ( 70 ) by means of adhesive, thermal bonding, pressure bonding, mechanical bonding, ultrasonic bonding or combinations thereof.
11. The disposable absorbent article according to claim 1 , wherein said disposable absorbent article ( 100 ) is selected from the group consisting of baby diapers, adult diapers, baby pants, adult pants, adult incontinence undergarments or pads, sanitary napkins and panty liners.
12. The disposable absorbent article according to claim 1 , wherein one or more connecting lines ( 80 ) comprise regions having the second basis weight (bw 2 ) and regions having a third basis weight (bw 3 ), wherein the first basis weight (bw 1 ) is greater than the second basis weight (bw 2 ), and the second basis weight (bw 2 ) is greater than the third basis weight (bw 3 ).