Thin fluid absorbent core-absorbent paper
The present disclosure relates to fluid absorbent cores including at least one absorption layer, the layer including at least 80% by weight of water-absorbent polymer particles, 0 to 10% by weight of an adhesive and from 0 to 10% by weight of fibrous material, wherein the water-absorbent polymer particles within the absorption layer are water-absorbent polymer particles having a vortex of 40 s or less and having a roundness of 0.79 to 0.85 and/or a CRC of 38 g/g to 85 g/g.
1. A fluid absorbent core comprising:
at least one absorption layer, the at least one absorption layer comprising at least 80% by weight of water-absorbent polymer particles,
0 to 10% by weight of an adhesive, and
from 0 to 10% by weight of fibrous material,
wherein the water-absorbent polymer particles within the at least one absorption layer are water-absorbent polymer particles having a vortex of 40 s or less and having a roundness of 0.79 to 0.85 and a centrifuge retention capacity (CRC) of 38 g/g to 85 g/g;
wherein the water-absorbent polymer particles have a free swell capacity (FSC) (1 min) of at least 25 g/g/s.
2. The fluid absorbent core according to claim 1 , comprising at least two absorption layers, an upper layer and a bottom layer, wherein at least the bottom layer comprises water-absorbent polymer particles.
3. The fluid absorbent core according to claim 2 , wherein a nonwoven material is sandwiched between the upper layer and the bottom layer.
4. The fluid absorbent core according to claim 2 , wherein a Water Pouring Time is 28 s or less and a Water Pouring Rewet 3.5 g or less measured for an absorbent core according to a water pouring test.
5. The fluid absorbent core according to claim 2 , wherein a Liquid Diffusion Length is at least 245 mm, a total strike-thru time 45 s or less and a Total Rewet 40 g or less measured for an absorbent core according to a strike-thru/rewet method.
6. The fluid absorbent core according to claim 1 , wherein the water-absorbent polymer particles have a CRC of 40 g/g to 80 g/g.
7. The fluid absorbent core according to claim 1 , wherein the water-absorbent polymer particles have a roundness of 0.80 to 0.85.
8. The fluid absorbent core according to claim 1 , wherein the water-absorbent polymer particles have an extractables content of 10 wt % or less.
9. The fluid absorbent core according to claim 1 , wherein the water-absorbent polymer particles have a volumetric absorption under load (VAUL) (τ=21 g cm −2 ) of 1000 s or less.
10. The fluid absorbent core according to claim 1 , wherein the water-absorbent polymer particles have a liquid uptake of 20 g/g (T 20 ) of 1000 s or less.
11. The fluid absorbent core according to claim 1 , wherein the water-absorbent polymer particles have a difference between a wet weight of filter papers and a dry weight of the filter papers (SAP-Rewet) (3 min) of 1.5 g or less.
12. An absorbent article, comprising:
an upper liquid-pervious sheet,
a lower liquid-impervious sheet,
a fluid absorbent core according to claim 1 , and
an optional acquisition distribution layer between the upper liquid-pervious sheet and the fluid absorbent core.
13. The fluid absorbent core according to claim 1 , wherein the water-absorbent polymer particles within the at least one absorption layer are in the form of droplet polymers.
14. Water-absorbent polymer particles having a vortex of 40 s or less and having a roundness of 0.79 to 0.85 and a centrifuge retention capacity (CRC) of 38 g/g to 85 g/g;
wherein the water-absorbent polymer particles have a free swell capacity (FSC) (1 min) of at least 25 g/g/s.
15. The water-absorbent polymer particles according to claim 14 , wherein the water-absorbent polymer particles are in the form of droplet polymers.