Tailored hemicellulose in non-wood fibers for tissue products
A tissue sheet includes softwood fibers and treated non-wood fibers from plants in the Poaceae family, wherein the treated non-wood fibers have less than 15 percent hemicellulose. Also, a tissue sheet consists essentially of softwood fibers and treated non-wood fibers, wherein the treated non-wood fibers have less than 15 percent hemicellulose. Customizing the tensile index and Canadian standard freeness (CSF) of fibers in a tissue sheet includes treating non-wood fibers by removing a portion of hemicellulose from the non-wood fibers; forming a tissue sheet comprising softwood fibers and the treated non-wood fibers; and adjusting the portion of hemicellulose removed from the non-wood fibers to achieve a desired the tensile index and Canadian standard freeness (CSF) of the treated non-wood fibers.
1. A method of manufacturing a tissue sheet comprising the steps of:
dispersing a plurality of softwood fibers in water to form a first fiber slurry;
treating a plurality of non-wood fibers derived from one or more plants in the Poaceae family with a hemicellulose enzyme to yield treated non-wood fibers having less than 15 percent hemicellulose and a Canadian Standard Freeness (CSF) greater than about 350 ml;
dispersing the treated non-wood fibers to form a second fiber slurry;
dispersing the first and second fiber slurries onto a forming fabric to form a wet tissue web;
dewatering the wet tissue web to form a partially dewatered tissue web; and
drying the partially dewatered tissue web to form a dried tissue web.
2. The method of claim 1 , wherein the non-wood fibers are derived from the group consisting of wheat, corn, miscanthus, bamboo, and combinations thereof.
3. The method of claim 1 , further comprising the steps of dispersing a plurality of eucalyptus fibers to form a third fiber furnish slurry and dispersing the third fiber furnish onto a forming fabric with the first and second fiber furnishes to form a wet tissue web.
4. The method of claim 1 , further comprising the steps of dispersing a plurality of hardwood fibers to form a third fiber furnish slurry and dispersing the third fiber furnish onto a forming fabric with the first and second fiber furnishes to form a wet tissue web.
5. The method of claim 1 , wherein the first and second fiber slurries are dispersed onto the forming fabric in layers to form a wet tissue web having two outer layers and at least one inner layer.
6. The method of claim 5 , wherein an outer layer comprises treated non-wood fibers and the at least one inner layer comprises softwood fibers.
7. The method of claim 5 , wherein the at least one inner layer comprises treated non-wood fibers.
8. The method of claim 1 , wherein the treated non-wood fibers have at least 50 percent less hemicellulose than the same non-wood fibers without treatment.
9. The method of claim 1 , wherein the treated non-wood fibers have at least 70 percent less hemicellulose than the same non-wood fibers without treatment.
10. The method of claim 1 , wherein the dried tissue web has a lower tensile index compared to a tissue sheet comprising softwood fiber and eucalyptus fiber in the place of the treated non-wood fiber.
11. The method of claim 1 , wherein the treated non-wood fiber has a Water Retention Value (WRV) less than about 3.5.