Absorbent materials

Abstract

Provided is an absorbent material and a method of making an absorbent material. The absorbent material comprises a blend of a super-absorbent first type of gel-forming fiber with a second type of gel-forming fiber, wherein the super-absorbent first type of gel-forming fiber is formed from a super-absorbent polymer. Such absorbent materials are useful in the manufacture of absorbent articles such as wound dressings.

Claims

1. An absorbent material comprising: a blend of a super-absorbent first type of gel-forming fibre with a second type of gel-forming fibre, wherein the super-absorbent first type of gel-forming fibre is formed from a polyacrylate or a co-polymer thereof; and reinforcing fibres.

2. The absorbent material according to claim 1, wherein the second type of gel forming fibre is a polysaccharide.

3. The absorbent material according to claim 1, wherein the second type of gel forming fibre is not modified cellulose.

4. The absorbent material according to claim 2, wherein the second type of gel forming fibre is alginate.

5. The absorbent material according to claim 1, comprising at least 5% of the super-absorbent first type of gel-forming fibres, by weight of the total fibre content of the material.

6. The absorbent material according to claim 1, comprising no more than 50% of the super-absorbent first type of gel-forming fibres, by weight of the total fibre content of the material.

7. The absorbent material according to claim 1, wherein the reinforcing fibres are thermoplastic bicomponent fibres.

8. The absorbent material according to claim 1, wherein the reinforcing fibres are formed from non-modified cellulose.

9. The absorbent material according to claim 1, comprising at least 5% reinforcing fibres, by weight of the total fibre content of the material.

10. The absorbent material according to claim 1, comprising from 10% to 30%of the super-absorbent first type of gel-forming fibres, from 50% to 70% of the second type of gel-forming fibres and from 10% to 20% reinforcing fibres, by weight of the total fibre content of the material.

11. The absorbent material according to claim 10, comprising from 10% to 30% polyacrylate, from 50% to 70% alginate and from 10% to 20% reinforcing fibres, by weight of the total fibre content of the material.

12. An absorbent article cornprising the absorbent material according to claim 1.

13. The absorbent article according to claim 12, wherein the absorbent article is a wound dressing.

14. The absorbent material according to claim 1, wherein the reinforcing fibres are lyocell.

15. The absorbent material according to claim 1, wherein the material is made by a method comprising carding.

16. An absorbent material comprising: a blend of a super-absorbent first type of gel-forming fibre with a second type of gel-forming fibre, wherein the super-absorbent first type of gel-forming fibre is formed from a poiyacrylate or a co-polymer thereof; and at least 30% of the second type of gel-forming fibre by weight of the total fibre content of the material.

Description

EXAMPLES

Example 1

(1) Calcium alginate fibres were cut to approximately 50 mm length and mixed with polyacrylate fibres (SAF, purchased from Technical Absorbents Limited, Grimsby, UK) and/or a solvent spun cellulose fibre (TENCEL (), Lenzing Fibres AG) in the ratios presented in Table 1. The fibres were passed through a sample card and the resultant web was needle bonded. Comparative calcium alginate fabric containing no polyacrylate fibres was manufactured in a similar manner. The absorbency was measured by weighing a 5 cm5 cm piece of sample material (W.sub.1). Next, the sample was placed in Solution A at 37 C. for 30 minutes in a petri dish. Then, the square was lifted out of the petri-dish by holding the square by one corner, and the sample was allowed to drain for 30 seconds. The sample was then reweighed to obtain the end weight (W.sub.2). The fabric absorbency is given by ((W.sub.2-W.sub.1)/W.sub.1).

(2) TABLE-US-00001 TABLE 1 % (w/w) Absorbency (g/g) TENCEL Free Alginate (RTM) polyacrylate swell Retention 100 0 0 16 9 90 0 10 19 80 0 20 19 11 70 10 20 19 12 70 0 30 24 14 60 0 40 27 17 50 0 50 29 18 Commercial products Sorbsan (Calcium alginate) 17 AQUACEL (RTM) 16 DURAFIBER (RTM) 18

(3) In the absence of polyacrylate, the absorbency (free swell) of the material was less than that of the commercial products. The inclusion of at least 10% polyacrylate allowed the material to absorb at least as much solution as the commercial products.

Example 2

(4) The lateral wicking of the material was determined by laying a 15 mm100 mm strip of fabric in a petri dish and subsequently adding 1 g of a saline solution coloured with a blue dye to the centre of the strip using a dropping pipette. The spread of the blue dyed area at the widest point was measured. This was performed in triplicate.

(5) TABLE-US-00002 Mean lateral wicking (mm) % 20 3.3 polyacrylate 30 2.3 DURAFIBER (RTM) 2.5 AQUACEL (RTM) 2.4

(6) Surprisingly, it was found that material comprising 20% polyacrylate had a mean lateral wicking which was significantly improved over that of the commercial products. Increasing the amount of polyacrylate to 30% resulted in a lateral wicking value which was substantially the same as that of the commercial products.