Cellulosic products using high-bulk cellulosic fibers

• US 5,840,787 A
• Filed: 09/30/1996
• Issued: 11/24/1998
• Est. Priority Date: 03/25/1994
• Status: Expired due to Term

• Current Assignee: Weyerhaeuser NR Company (Weyerhauser)
• Original Assignee: Weyerhaeuser Company (Weyerhauser)
• Inventors: Dudley, Dwight Albert II, Shearer, Dwayne M., Neogi, Amar N., West, Hugh
• Primary Examiner(s): Szekely, Peter A.
• Application Number:
  US08/723,325
• Time in Patent Office: 785 Days
• Field of Search: 524/13, 524/14, 524/15, 524/16, 524/35, 525/54.21, 106/163.1, 106/210, 169/2157.6
• US Class Current: 524/35
• CPC Class Codes: A61L 15/24 Macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds; Derivatives thereof A61L15/225 takes precedence
• CPC Class Codes: A61L 15/28 Polysaccharides or their derivatives A61L15/225 takes precedence
• CPC Class Codes: C08B 15/10 Crosslinking of cellulose
• CPC Class Codes: C08L 1/00 Compositions of cellulose, modified cellulose or cellulose derivatives
• CPC Class Codes: C08L 1/08 Cellulose derivatives
• CPC Class Codes: C08L 2666/02 Organic macromolecular compounds, natural resins, waxes or and bituminous materials
• CPC Class Codes: C08L 35/00 Compositions of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a carboxyl radical, and containing at least one other carboxyl radical in the molecule, or of salts, anhydrides, esters, amides, imides or nitriles thereof; Compositions of derivatives of such polymers
• CPC Class Codes: D21C 9/005 organic compounds
• CPC Class Codes: D21H 11/20 Chemically or biochemically modified fibres
• CPC Class Codes: D21H 17/07 Nitrogen-containing compounds
• CPC Class Codes: D21H 17/15 Polycarboxylic acids, e.g. maleic acid
• CPC Class Codes: D21H 17/28 Starch

Abstract

A fiber/binding agent composition comprising: individualized chemically crosslinked high-bulk fibers comprising individualized fibers chemically intra-fiber crosslinked with a crosslinking agent that is a polycarboxylic acid or is selected from the group of urea derivatives consisting of methylated urea, methylated cyclic ureas, methylated lower alkyl substituted ureas, dihydroxy cyclic ureas, and methylated dihydroxy cyclic ureas, and mixtures thereof; and from about 0.1 to about 6 weight percent of a water-borne binding agent. The water-borne binding agent is selected from the group consisting of starch, a polyvinyl alcohol, a polyvinyl acetate latex, a polyethylene/acrylic acid copolymer, an acrylic acid polymer, an oxidized polyethylene, a polyvinyl chloride, a polyvinyl chloride/acrylic acid copolymer, an acrylonitrile/butadiene/styrene copolymer and polyacrylonitrile.

Claims

1. A fiber-binder sheet or pad product wherein adjacent fibers are in contact and form plural fiber crossover points which comprises:

from 0.5-100.0 weight percent chemically intrafiber crosslinked high bulk cellulosic fibers in admixture with 99.5-0.0 weight percent conventional cellulose fibers; and

from about 0.1 to about 6 weight percent of a water borne binding agent, said binding agent being more heavily concentrated at the fiber--fiber crossover points of crosslinked fibers with each other and with other fibers during removal of water from the product, whereby the binder more effectively contributes strength and integrity to the structure.

2. The product of claim 1 wherein the water-borne binding agent is anionic, nonionic, or cationic.

3. The product of claim 1 wherein the water-borne binding agent is selected from the group consisting of a starch, a modified starch, a polyvinyl alcohol, a polyvinyl acetate, a polyethylene/acrylic acid copolymer, an acrylic acid polymer, a polyacrylate, a polyacrylamide, a polyamine, guar gum, an oxidized polyethylene, a polyvinyl chloride, a polyvinyl chloride/acrylic acid copolymer, an acrylonitrile/butadiene/styrene copolymer and polyacrylonitrile.

4. The product of claim 3 wherein the binding agent is selected from the group consisting of starch and modified starch.

5. The product of claim 3 wherein the binding agent is polyvinyl alcohol.

6. The product of claim 1 wherein the product comprises from about 0.25 weight percent to about 5 weight percent water-borne binding agent.

7. The product of claim 1 further including from about 5 weight percent to about 99.5 weight percent conventional fiber furnish.

8. The product of claim 1 further including at least about 90 weight percent conventional fiber furnish.

9. The product of claim 1 further including at least about 80 weight percent conventional fiber furnish.

10. The product of claim 1 wherein said high bulk fibers are individualized prior to forming said sheet or pad product.

11. The product of claim 1 in which the density is less than about 0.6 g/cm³ which corresponds to a bulk greater than about 1.7 cm³ /g.