Curled fiber mats and methods of making and using same
Disclosed herein are The invention relates to curled fiber mats. The invention further includes methods of making curled fiber mats, comprising forming a fibrous media from a fibrous material, treating the fibrous media with a crosslinking agent to form a treated fibrous media, and drying and/or curing the treated fibrous media to produce a curled fiber mat that has a permanent curl.
1. A method comprising:
forming not previously curled fiber mat comprising bicomponent fibers and not previously curled cellulosic pulp fibers,
treating the not previously curled fiber mat with a crosslinking agent to form a treated not previously curled fiber mat, and
drying and/or curing the treated not previously curled fiber mat to produce a curled fiber mat,
wherein the step of drying and/or curing the treated fiber mat produces curled cellulosic fibers,
wherein the curled cellulosic fibers are crosslinked internally by the crosslinking agent to form permanently curled cellulosic fibers, and
wherein the curled fiber mat comprises bicomponent fibers that are bonded with the permanently curled cellulosic pulp fibers.
2. The method of claim 1 , wherein the drying is at a temperature of 100° 0 C. or greater.
3. The method of claim 1 , wherein the drying is for a time from 10 seconds to 10 minutes.
4. The method of claim 1 , wherein the curing is at a temperature of 145° C. or greater.
5. The method of claim 1 , wherein the curing is at a temperature of 180° C. to 190° C.
6. The method of claim 1 , wherein the curing is for a time from 30 seconds or greater.
7. The method of claim 1 , wherein the curing is for a time from 30 seconds to 5 minutes.
8. The method of claim 1 , wherein the drying occurs before and separate from the curing.
9. The method of claim 1 , wherein the curing and the drying occur simultaneously.
10. The method of claim 1 , wherein the crosslinking agent comprises a carboxylic acid.
11. The method of claim 1 , wherein the crosslinking agent is selected from the group consisting of citric acid, glutaraldehyde, and combinations thereof.
12. The method of claim 1 , wherein the crosslinking agent is present in an amount of 3.5% to 20%, based on the weight of the not previously curled fiber mat.
13. The method of claim 1 , wherein the crosslinking agent comprises citric acid and a hypophosphite.
14. The method of claim 13 , wherein the citric acid is added in an amount of at least 0.5% by weight, based on the weight of the not previously curled fiber mat, and
wherein the citric acid and the hypophosphite are in a ratio of 1 citric acid to 0.2-0.4 hypophosphite based on the weight of the not previously curled fiber mat.
15. The method of claim 1 , wherein the curled fiber mat has a final curl index of 0.28 or greater.
16. The method of claim 1 , wherein the curled fiber mat has a thickness of 0.5 mm to 3 mm.
17. The method of claim 1 , wherein the curled fiber mat is a curled fiber airlaid mat or a curled fiber wetlaid mat.
18. The method of claim 1 , wherein the not previously curled fiber mat is made by an airlaid process or a wetlaid process.
19. The method of claim 1 , wherein the not previously curled cellulosic pulp fibers comprise not previously curled Kraft pulp fibers.