# US 10,501,891 B1 · Crosslinking cellulose with Glyoxal to improve absorption properties > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,501,891 B1 - Document ID: US10501891B1 - Status: Granted - Kind: B1 - Application number: 16/257,760 - Filed: 2019-01-25 - Granted: 2019-12-10 - Earliest claimed: 2019-01-25 - Assignees: Rayonier Performance Fibers, LLC - Applicants: Rayonier Performance Fibers, LLC - Inventors: Michael Washburn - Web page: https://patentgrep.com/patent/US10501891B1 ## CPC - D21H 11/20: Chemically or biochemically modified fibres - A61F 13/53747: {the layer is facing the topsheet (layer is part of the topsheet A61F13/511)} - C08B 15/10: Crosslinking of cellulose - C08K 5/07: Aldehydes; Ketones - C08L 1/02: Cellulose; Modified cellulose - A61F 2013/530051: {being made in cross-linked cellulosic fibres} - A61F 2013/530737: {by the absorbent capacity} - C08L 2205/16: Fibres; Fibrils - C08L 2312/00: Crosslinking - D21C 9/005: {organic compounds} - D21H: PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR - A61F: FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS (dental prosthetics A61C) - C08B: POLYSACCHARIDES; DERIVATIVES THEREOF (polysaccharides containing less than six saccharide radicals attached to each other by glycosidic linkages C07H; fermentation or enzyme-using processes C12P19/00; sugar industry C13; production of cellulose D21) - C08K: Use of inorganic or non-macromolecular organic substances as compounding ingredients (paints, inks, varnishes, dyes, polishes, adhesives C09) - C08L: COMPOSITIONS OF MACROMOLECULAR COMPOUNDS (compositions based on polymerisable monomers C08F, C08G; artificial filaments or fibres D01F; textile treating compositions D06) - D21C: PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR ## Abstract The present invention is directed to a novel dialdehyde based reagent that is neutralized, wherein the preparation of the reagent includes the steps of provide a dialdehyde; provide a caustic soda; mix both reagents until pH of the dialdehyde is 5.5 to 7.5; and stir the mixture. ## Claims ### Claim 1 A dialdehyde based reagent, which consists of: a solution of dialdehyde and a caustic soda in water, wherein the solution has a pH of about 5.5 to 7.5, and wherein the dialdehyde is 2.0% by weight in the solution. ### Claim 2 (depends on 1) The dialdehyde based reagent of claim 1, wherein the reagent is suitable for making liquid surge fiber. ### Claim 3 (depends on 2) The dialdehyde based reagent of claim 2, wherein the surge fiber is useful as a surge layer in an absorbent article. ### Claim 4 (depends on 1) The dialdehyde based reagent of claim 1, wherein the dialdehyde is selected from glyoxal, glutaraldehyde, 1,4-cyclohexane dicarbaldehyde, and 1,3-cyclohexane dicarbaldehyde, and mixtures thereof. ### Claim 5 (depends on 1) The dialdehyde based reagent of claim 1, wherein the caustic soda is sodium hydroxide or potassium hydroxide. ### Claim 6 (depends on 1) A method of making liquid surge fiber, comprising: providing a solution of the dialdehyde based reagent of claim 1; providing cellulosic fiber derived from wood pulp; applying the solution of the dialdehyde based reagent to the cellulosic fibers to impregnate the cellulosic fibers; and drying the treated cellulosic fibers. ### Claim 7 (depends on 6) The method of claim 6, wherein the solution of the dialdehyde based reagent is applied to the cellulosic fiber by spraying, dipping or applying with a puddle press, size press or a blade-coater. ### Claim 8 (depends on 6) The method of claim 6, wherein the cellulosic fiber is provided in sheet or roll form. ### Claim 9 (depends on 6) The method of claim 6, wherein the solution of the reagent is applied to the cellulosic fibers to provide 1 wt % to about 3 wt % of dialdehyde based reagent on the fiber. ### Claim 10 (depends on 6) The method of claim 6, wherein the cellulosic fiber is a cellulose fiber selected from the group consisting of: hardwood cellulose pulp, softwood cellulose pulp obtained from a kraft or sulfite chemical process, caustic-treated pulp and combinations and mixtures thereof. ### Claim 11 (depends on 6) The method of claim 6, wherein the drying is conducted at a temperature within the range of about 120° C. to about 160° C. ### Claim 12 (depends on 6) The method of claim 6, wherein the treated cellulosic fibers are dried for a period that affords the fibers with a moisture content of less than 7%. ### Claim 13 (depends on 1) A cellulose fiber which is crosslinked by the dialdehyde based reagent of claim 1. ### Claim 14 (depends on 13) An article of manufacture comprising the cellulose fiber of claim 13. ### Claim 15 (depends on 1) A composition consisting of the dialdehyde based reagent according to claim 1 and cellulose fibers derived from wood pulp. ### Claim 16 (depends on 15) A composition according to claim 15, wherein the concentration of the dialdehyde based reagent to cellulose fibers is 0.5 to 3.0 wt % of reagent to fibers. ### Claim 17 (depends on 1) A composition consisting of cellulose fibers derived from wood pulp, which are crosslinked with the dialdehyde based reagent according to claim 1. ### Claim 18 (depends on 17) The composition according to claim 17, wherein the fibers have a free swell (FS) greater than about 9.0 g/g, and an absorbency under load of 0.3 psi of greater than about 8.0 g/g. ### Claim 19 (depends on 1) A method of making a liquid surge fiber, comprising: providing a solution of the dialdehyde based reagent of claim 1, applying the solution of the dialdehyde based reagent to cellulosic fibers derived from wood pulp in sheet form to impregnate the cellulosic fibers, removing excess solution from the cellulosic fibers by pressing to a desired pickup, and drying and curing the cellulosic fibers at a temperature not higher than 135° C. for a period sufficient to afford completely dry cellulosic fibers. ### Claim 20 (depends on 19) The method of claim 19, wherein the completely dry cellulosic fibers contain less than 30.0% knots and fines and has and ISO brightness of over 80%.