High brightness non-wood pulp
Disclosed are non-wood pulps having a fiber length greater than about 1.70 mm and a brightness of about 80% or greater. The relatively high degree of brightness is achieved without a loss fiber length or pulp yield. The high degree of brightness and relatively long fiber length makes the pulps well suited for the manufacture of wet-laid fibrous products, particularly wet-laid tissue products. The pulps may be prepared from plants of the family Asparagaceae by mechanical pulping and more preferably by a chemi-mechanical pulping using a sodium hydroxide alkaline peroxide solution where the primary pulp is cleaned to reduce debris prior to bleaching. Preferably the cleaned primary pulp has less than about 5% debris prior to bleaching.
1. A non-wood pulp comprising a plurality of fibers derived from a plant of the family Asparagaceae, the non-wood pulp having a fines content of less than about 2.0%, a Freeness from about 400 mL to about 700 mL, a fiber length from about 1.70 to about 2.50 m, and a brightness of about 80% or greater.
2. The non-wood pulp of claim 1 comprising 1% or less of debris.
3. The non-wood pulp of claim 1 comprising 0.6% or less of debris.
4. The non-wood pulp of claim 1 having a brightness from about 80 to about 92%.
5. The non-wood pulp of claim 1 having a coarseness from about 4.0 to about 10.0 mg/100 m and a porosity from about 100 to about 450 cfm.
6. The non-wood pulp of claim 1 having a Tensile Index of at least about 20 Nm/g and a porosity from about 100 to about 450 cfm.
7. The non-wood pulp of claim 1 wherein the plurality of fibers are derived from one or more plants of the genus Hesperaloe.
8. The non-wood pulp of claim 7 wherein the one or more plants are selected from H. funifera, H. parviflora, H. nocturna, H. chiangii, H. tenuifolia, H. engelmannii and H. malacophylla.
9. The non-wood pulp of claim 1 having a Freeness from about 400 to about 600 mL.
10. A chemi-mechanical non-wood pulp comprising a plurality of fibers derived from one or more plants of the genus Hesperaloe and having a Freeness from about 400 to about 600 mL, a fiber length from about 2.00 to about 2.50 mm, a brightness of at least about 80%, and about 1% or less of debris.
11. The chemi-mechanical non-wood pulp of claim 10 having a coarseness less than about 10.0 mg/100 m.
12. The chemi-mechanical non-wood pulp of claim 10 having a fines content of less than about 2.0%.
13. The chemi-mechanical non-wood pulp of claim 10 having a Very Long Fiber (VFL) content of about 0.10% or less.