With Chemical Or Physical Modification Of Liberated Fiber Patents (Class 162/9)
  • Patent number: 6080277
    Abstract: Cellulose particles are provided which have cationic groups even in the interior.
    Type: Grant
    Filed: October 14, 1997
    Date of Patent: June 27, 2000
    Assignee: TFM Handels-Aktiengesellschaft
    Inventors: Jorg Oberkofler, Thomas Moser, Anton Schmalhofer, Jeffrey F. Spedding
  • Patent number: 6059924
    Abstract: An improved method of preparing a fluff pulp sheet used to produce fluffed pulp exhibiting enhanced dry compression and liquid wicking and retention characteristics using typical paper-making equipment, wherein a chemical pulp slurry is mildly refined prior to the steps of sheet formation, pressing and drying.
    Type: Grant
    Filed: January 2, 1998
    Date of Patent: May 9, 2000
    Assignee: Georgia-Pacific Corporation
    Inventor: Martin G. Hoskins
  • Patent number: 5958180
    Abstract: Processes for increasing the strength of cellulosic fibers are carried out by contacting relatively dry cellulosic fibers with an agent in particulate or vapor form comprising a carboxylic acid cyclic anhydride at an elevated temperature for a time sufficient to significantly increase the bonding strength of the fibers. The treated fibers bond more readily to one another and they also hold wet and dry strength aids more strongly. Furthermore, the treatment does not significantly affect the internal chemical structure of the fibers so that paper made from the fibers exhibits overall improved dimensional stability.
    Type: Grant
    Filed: September 23, 1997
    Date of Patent: September 28, 1999
    Assignee: International Paper Company
    Inventors: Martin A. Hubbe, Dinkar G. Wagle, Erwin R. Ruckel
  • Patent number: 5935383
    Abstract: The invention is a method for improving the efficiency of aqueous cationic wet strength additives by pretreating cellulose surfaces with reactive anionic compounds, thus providing the cellulose surface with additional anionic sites suitable for retaining a high proportion of said cationic wet strength additives on the cellulose. The wet strength additives on the cellulose surface are cured or reacted with the cellulose surface. The resulting fibrous material has unusually high wet strength with unusually low doses of cationic wet strength additive. The preferred reactive anionic compounds comprise compounds having a reactive group suitable for covalent bonding to hydroxyl groups on cellulose, and further having sulfonic or other anionic end groups capable of attracting cationic wet strength compounds in aqueous solution. The invention also includes means of preventing photoyellowing of high-yield fibers while simultaneously improving wet strength performance.
    Type: Grant
    Filed: March 6, 1998
    Date of Patent: August 10, 1999
    Assignee: Kimberly-Clark Worldwide, Inc.
    Inventors: Tong Sun, Jeffrey Dean Lindsay
  • Patent number: 5928470
    Abstract: Metal oxides or metal hydroxides, such as titanium dioxide, are incorporated into papermaking fibers by absorbing an organometallic compound into the fiber walls while the fibers are dry or slurried with a non-aqueous solvent and thereafter contacting the ester-containing fibers with water to precipitate the metal oxides or metal hydroxides. The resulting modified fibers can provide greater opacity and other improved properties to papers made from such fibers.
    Type: Grant
    Filed: November 7, 1997
    Date of Patent: July 27, 1999
    Assignee: Kimberly-Clark Worldwide, Inc.
    Inventor: Thomas Gerard Shannon
  • Patent number: 5914003
    Abstract: Cellulose is effectively oxidized with nitrogen dioxide in a hydrofluoroether solvent.
    Type: Grant
    Filed: June 9, 1998
    Date of Patent: June 22, 1999
    Assignee: Mach I, Inc.
    Inventors: Brian M. Kosowski, Bernard M. Kosowski
  • Patent number: 5906894
    Abstract: A multi-ply paperboard comprising at least one ply of conventional cellulose fibers and from about 0.1 to about 6 weight percent of a water-borne binding agent; and at least one ply containing up to 20% of chemically intra-fiber crosslinked cellulosic high-bulk fibers and from about 0.1 to about 6 weight percent of a water-borne binding agent. The water-borne binding agent may be 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 or polyacrylonitrile. A method for making the paperboard is disclosed.
    Type: Grant
    Filed: October 4, 1996
    Date of Patent: May 25, 1999
    Assignee: Weyerhaeuser Company
    Inventors: Hugh West, Amar N. Neogi, Dwight A. Dudley, II, Dwayne M. Shearer
  • Patent number: 5873979
    Abstract: In preparing individualized polycarboxylic acid crosslinked fibers, defibration requirements are reduced to obtain a particular wet responsiveness and satisfactory absorbency properties are maintained even without washing or bleaching and washing, and improved dry resiliency is obtained, by using a reduced surface tension solution of polycarboxylic acid crosslinking agent.
    Type: Grant
    Filed: June 3, 1997
    Date of Patent: February 23, 1999
    Assignee: The Procter & Gamble Company
    Inventor: Shahrokh A. Naieni
  • Patent number: 5843278
    Abstract: A method of producing a soft paper product incudes, a) providing a pulp sheet at a moisture content of no greater than about 10%, the pulp of said sheet not having been previously subjected to dry milling and not being predominately anfractuous; b) treating the pulp sheet at moisture content of no greater than about 10% with liquid ammonia of a concentration of at least 90% for a period of time less than or equal to about 60 seconds effective to increase degree of softness in the sheet of pulp from that existing prior to the treating, the pulp in the treated sheet remaining not predominately anfractuous after said treating; c) forming the treated pulp sheet into a papermaking slurry; and d) feeding the papermaking slurry into the headbox of a paper machine and producing a tissue paper product therefrom which has greater softness than a tissue paper product made from the same pulp which has not been so treated with said ammonia.
    Type: Grant
    Filed: February 14, 1997
    Date of Patent: December 1, 1998
    Assignee: Potlatch Corporation
    Inventors: Gopal C. Goyal, Robert E. Packwood, Jr., Mary L. Minton
  • Patent number: 5840249
    Abstract: A method for improving products such as toothpaste, shampoo, soap, detergent and lotions or creams and such improved products. The products are improved by adding a hydrous cellulose pulp that has an unlimited shelf life to the product. The hydrous cellulose pulp is resistant to decomposition and can be produced either by recycling waxed paper or through a process that begins with virgin vegetable constituents and wax. During the defibering process an emulsifier is added to the slurry and its temperature is elevated to 150.degree.-190.degree. Fahrenheit.
    Type: Grant
    Filed: February 28, 1997
    Date of Patent: November 24, 1998
    Inventor: Bernard Bendiner
  • Patent number: 5834095
    Abstract: Disclosed is a process for treating cellulosic fibers using high temperatures that is effective to result in modified cellulosic fibers that exhibit desired properties such as water retention values and wet curl values. The high temperature process is quite efficient and has been found to produce cellulosic fibers that are essentially uniformly treated. Also disclosed is a handsheet prepared from the treated cellulosic fibers for use in disposable absorbent products.
    Type: Grant
    Filed: December 17, 1996
    Date of Patent: November 10, 1998
    Assignee: Kimberly-Clark Worldwide, Inc.
    Inventors: Jacek Dutkiewicz, Krzysztof Andrzej Szymonski, Gerard Martin Aberson, Tong Sun
  • Patent number: 5779736
    Abstract: The present invention discloses a process for producing a fibrillated cellulose acetate fiber comprising contacting cellulose acetate fiber with a strong base solution at conditions sufficient to remove greater than about 5% of bulk acetyl groups from said cellulose acetate fiber. Modified cellulose acetate staple fiber comprising an outer layer of regenerated cellulose in which at least about 5% of the acetyl groups are removed on an overall fiber basis are also disclosed. Paper products incorporating said fibers are also disclosed.
    Type: Grant
    Filed: January 19, 1995
    Date of Patent: July 14, 1998
    Assignee: Eastman Chemical Company
    Inventors: Tim J. Frederick, Melvin G. Mitchell, Lee R. Partin, Alan K. Wilson, Richard D. Neal
  • Patent number: 5779857
    Abstract: Defibrated cellulose product comprising a fibrous structure having good compressibility under the influence of heat and pressure. The structure is obtained by cross-linking, in a dry state, cellulose fibers which are impregnated with cross-linking agent and at least one polyfunctional alcohol, and which a difibrated prior to carrying out the cross-linking reaction. The cross-linking reaction is carried out at an elevated temperature of at least 110.degree. C.
    Type: Grant
    Filed: November 30, 1995
    Date of Patent: July 14, 1998
    Assignee: Stora Kopparbergs Bergslags Aktiebolaf
    Inventor: Leif Norlander
  • Patent number: 5759349
    Abstract: This invention relates to the application of an optically active dye or fluorecent whitening agent within a paper fiber such that the dye or whitening agent does not migrate out of the fiber at a level of toxicological concern. Such processes of this type, generally, allow the dye or whitening agent to be used in hygienic end use applications.
    Type: Grant
    Filed: July 25, 1997
    Date of Patent: June 2, 1998
    Assignee: Westvaco Corporation
    Inventors: James Joseph Foster, Roger Wayne Ogden
  • Patent number: 5755828
    Abstract: Crosslinked cellulose fibers having free pendant carboxylic acid groups are disclosed. The fibers include a polycarboxylic acid covalently coupled to the fibers, and are crosslinked with a crosslinking agent having a cure temperature lower than the cure temperature of the polycarboxylic acid. Methods for producing the fibers and for producing a fibrous sheet incorporating the fibers are also disclosed.
    Type: Grant
    Filed: December 18, 1996
    Date of Patent: May 26, 1998
    Assignee: Weyerhaeuser Company
    Inventor: John A. Westland
  • Patent number: 5725601
    Abstract: A water absorbent cross-linked, carboxyalkylated cellulose-containing material is produced by impregnating a cellulose-containing material with an aqueous reaction solution including a carboxyalkylating agent, an alkali metal hydroxide, and a cross-linking agent dissolved in water in an initial content of 50 to 90% by weight, the molar ratio of the carboxylating agent to glucose groups of cellulose being 0.7 to 2.0; adjusting the water content of the aqueous reaction solution impregnated in the cellulose-containing material to 20 to 60% by weight and of at least 5% by weight below the initial water content by evaporating a portion of water; and subjecting the water content-adjusted cellulose-containing material to a simultaneous cross-linking and carboxylating reaction procedure at 50.degree. to 110.degree. C., while maintaining the water content at 20 to 60% and of at least 5% by weight below the initial water content.
    Type: Grant
    Filed: August 1, 1996
    Date of Patent: March 10, 1998
    Assignee: New Oji Paper Co., Ltd.
    Inventors: Kozo Tajiri, Masayo Maeda, Haruo Tsukamoto
  • Patent number: 5709774
    Abstract: Heat-treated-in-air high lignin content cellulosic fibers which are free of moieties from crosslinking agents, for use in absorbent structures, are prepared by fluffing high lignin content fibers at a consistency of at least 40%, and heating in air at atmospheric pressure at a temperature ranging from 120.degree. C. to 280.degree. C. fluffed fiber water admixture having a consistency of at least 60% or moisture-free fluffed fibers, to remove any moisture content and heat treat the resulting moisture-free high lignin content fibers for at least 5 seconds, or by heating a sheet of dry (0-40% moisture content) high lignin content fibers utilizing these same heating conditions and then fluffing.
    Type: Grant
    Filed: April 26, 1996
    Date of Patent: January 20, 1998
    Assignee: The Procter & Gamble Company
    Inventor: Shahrokh A. Naieni
  • Patent number: 5705383
    Abstract: The present invention relates to the use of certain fungi in the reduction of the pitch and/or lignin content of cellulosic materials. In particular, the white rot fungi Schizophyllum commune, Trichaptum biforme and Phanerochaete gigantea are useful in reducing pitch and/or lignin, or both, which saves electrical energy during the mechanical refining of pulps and pulpwoods used in making cellulosic products.
    Type: Grant
    Filed: September 29, 1995
    Date of Patent: January 6, 1998
    Assignee: Clariant Finance (BVI) Limited
    Inventors: Robert A. Blanchette, Sara Iverson, Chad J. Behrendt
  • Patent number: 5698074
    Abstract: Disclosed is a fiber comprising, chemically bonded together, (a) a conventional cellulosic fiber, such as a Kraft fiber or a chemithermomechanical pulp fiber; (b) poly(acrylate-co-itaconate) copolymer, such as the acid form of a poly(acrylate-co-itaconate) copolymer comprising 90-95 mole % acrylate and 5-10 mole % itaconate having weight average molecular weight of about 600,000-900,000; and (c) a polyol, such as polyethylene glycol; also disclosed are methods for making such fibers, especially evaporatively depositing an intimate mixture of the copolymer and polyol on the fiber followed by thermally crosslinking at specific temperatures for limited periods; absorbent paper which can be made by wet-laying the fiber, especially in admixture with conventional fiber; and derivative paper structures, such as multi-ply disposable absorbent towels.
    Type: Grant
    Filed: May 1, 1995
    Date of Patent: December 16, 1997
    Assignee: The Procter & Gamble Company
    Inventors: Robert Lee Barcus, David William Bjorkquist
  • Patent number: 5691193
    Abstract: A process for the bleaching of kraft pulps with non-chlorine chemicals, employing a sequential reaction of oxidative enzymes and hydrogen peroxide. The kraft pulp can be from conventional or extended pulping, or from an oxygen delignification step. The enzyme reaction is monitored by methanol release which results from the demethylation of lignin. The process essentially comprises three steps. The first step is the oxidation of kraft pulp either with manganese peroxidase enzyme in the presence of Mn(II) salts, hydrogen peroxide and chelator, or with laccase enzyme preferably in the presence of 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS), or a combination of both enzymes in a crude mixture as typically produced by certain fungi. The Mn(II) salts and chelator may already be present in sufficient amount in the pulp. This first step is performed at an acidic pH, and moderate temperatures for a period of time between 30 and 240 minutes.
    Type: Grant
    Filed: June 23, 1994
    Date of Patent: November 25, 1997
    Assignee: Pulp and Paper Research Institute of Canada
    Inventors: Michael Geoffrey Paice, Robert Ernest Bourbonnais
  • Patent number: 5679220
    Abstract: A method for enhancing the deposition and retention of particulate filler on papermaking fibers. In a first vessel, there is formed a slurry of papermaking fibers and in a second vessel there is formed a slurry of lime or its equivalent. The fiber slurry is at a consistency of not greater than about 5%. These separately formed slurries are thereafter combined with a gaseous precipitant in a flow reactor and under conditions whereby the gaseous precipitant is subjected to rapid shear and calcium carbonate is deposited in situ on the fibers. Unexpectedly, the reaction time for the formation and deposition of the calcium carbonate filler is very rapid. Control over the pH of the reactants in the reactor is achieved through the sequence of introduction of the reactants to the reactor. Also, through selection of the molar ratio of the gaseous precipitant and lime, the morphology of the calcium carbonate crystals may be controlled.
    Type: Grant
    Filed: January 19, 1995
    Date of Patent: October 21, 1997
    Assignee: International Paper Company
    Inventors: M. C. Matthew, Sanjay Patnaik, Paul Hart, Thomas Amidon
  • Patent number: 5665205
    Abstract: A high level of calcium carbonate filler is added to secondary fiber pulp by in situ attachment to the secondary fibers. The secondary fiber pulp is mixed with an alkaline salt such as calcium oxide or calcium hydroxide and contacted with a reaction gas such as carbon dioxide in a gas-liquid contactor apparatus through efficient mixing in order to precipitate filler material such as calcium carbonate crystal complexes on the secondary fibers. The resulting pulp products have comparable or, in some cases, better brightness, cleanliness, and other sheet properties as compared to filler addition by conventional methods.
    Type: Grant
    Filed: January 19, 1995
    Date of Patent: September 9, 1997
    Assignee: International Paper Company
    Inventors: Narendra R. Srivatsa, Sanjay Patnaik, Paul Hart, Thomas E. Amidon, Jean J. Renard
  • Patent number: 5662773
    Abstract: The present invention discloses a process for treating filter rods comprising cellulose acetate tow waste comprising the steps of:a. cutting said filter rods so that fiber of said cellulose acetate have a fiber length of less than about 4 inches; andb. treating said cut filter rods with an aqueous base until at least 5% of acetyl groups on said cellulose acetate has been hydrolyzed.Filter rods treated in this manner are suitable for use in various paper products. The process of the present invention may further include a step for repulping the cut filter rods to repulp any included plugwrap.Modified fiber comprising cellulose acetate wherein at least 5% of acetyl groups on said cellulose acetate have been hydrolyzed, said fiber having a length of less than about 4 inches, are also disclosed.Paper products comprising between about 5 and about 90% of the fiber of claim 21 and paper pulp are also disclosed.
    Type: Grant
    Filed: January 19, 1995
    Date of Patent: September 2, 1997
    Assignee: Eastman Chemical Company
    Inventors: Tim J. Frederick, Melvin G. Mitchell, Lee R. Partin
  • Patent number: 5597730
    Abstract: A method for degrading coal tar, coal tar distillation fractions, and organic compounds, specially those compounds having three or more fused rings of the type often associated with coal tar, whether derived from coal tar or synthesized independently. According to the present invention degradation takes place by means of the nonspecific degradation reaction used by white rot fungi to degrade lignin. The degradation reaction occurs in part by means of a lignin degrading enzyme and hydrogen peroxide, both produced by white rot fungi.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: January 28, 1997
    Assignee: Utah State University Foundation
    Inventors: Steven D. Aust, John A. Bumpus
  • Patent number: 5573640
    Abstract: A composition of paper comprising 99 to 10 weight percent cellulose fibers and 1 to 90 weight percent cored cellulose fibers that are uniformly dispersed within the paper. The cored cellulose fibers are composed of a cellulose sheath that is 4 to 15 weight percent of the weight of the fiber and a cellulose acetate core. The cored cellulose fibers contain no substantial crimp and have an average length of 1 to 7 mm, a density of 1.20 to about 1.35 gm/cc, a denier 1 to 30 grams per 9,000 meters and a uniform dispersion index of less than 0.15.
    Type: Grant
    Filed: July 28, 1995
    Date of Patent: November 12, 1996
    Assignee: Eastman Chemical Company
    Inventors: Tim J. Frederick, Melvin G. Mitchell, Lee R. Partin
  • Patent number: 5567272
    Abstract: The present invention relates to a process for recycling silicone-coated paper by disintegration and new formation of sheets, which comprises carrying out the disintegration in the presence of one or more salts of monophosphoric esters.
    Type: Grant
    Filed: August 28, 1995
    Date of Patent: October 22, 1996
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Peter Hentzschel, Walter Kamutzki, Dieter Wolf
  • Patent number: 5562740
    Abstract: Disclosed is a process for making reduced odor individualized, crosslinked fibers which includes the steps of providing cellulosic fibers, contacting the fibers with a solution containing a C.sub.2 -C.sub.9 polycarboxylic acid crosslinking agent, mechanically separating the fibers into substantially individual form, drying the fibers and reacting the crosslinking agent with the individualized fibers to form intrafiber crosslink bonds. The individualized cellulosic fibers are then contacted with a strong alkaline solution and strong oxidizing agent to reduce the odor and increase the brightness. Preferably, the crosslinking agent is citric acid, and preferably, between about 1.0 weight % and about 12.0 weight % of the crosslinking agent reacts to form the intrafiber crosslink bonds. Preferably, the alkaline solution is an aqueous solution of sodium hydroxide, and preferably, about 0.09 weight % of the sodium hydroxide, on a dry fiber weight basis, is applied to the crosslinked fibers.
    Type: Grant
    Filed: June 15, 1995
    Date of Patent: October 8, 1996
    Assignee: The Procter & Gamble Company
    Inventors: Jeffery T. Cook, Walter D. Daniels, Pedro A. Rodriguez, Peter A. Graef, Clifford R. Bolstad, William L. Duncan
  • Patent number: 5536369
    Abstract: The invention relates to a fluff pulp for absorbent sanitary products consisting of cellulose with cross linkings between the cellulose molecules in the cellulose fibers, and a method for its preparation. The characteristics feature of the invention is that the chemical cross linkings between the cellulose molecules in the cellulose fibers are at least partly formed by a heterocyclic compound containing in addition to coal at least two nitrogen atoms in the ring. The specific volume of the pulp in wet state is at least 9 dm.sup.3 /kg, its absorption capacity >11 g/g, and its brightness (dry sheet) is at least >65% ISO.
    Type: Grant
    Filed: August 30, 1994
    Date of Patent: July 16, 1996
    Assignee: Stora Kopparbergs Bergslags Aktiebolag
    Inventor: Leif Norlander
  • Patent number: 5522967
    Abstract: Disclosed is a method for the surface modification of cellulose fiber and the resulting product, sulfonated cellulose. Cellulose is first oxidized, preferably with sodium metaperiodate (NaIO.sub.4), to form dialdehyde oxycellulose, which is then reacted with sodium bisulfite (NaHSO.sub.3) to produce sulfonated cellulose. Sulfonation of the cellulose fiber significantly increases the dry and wet tensile strength as well as the wet strength:dry strength ratio, making this modified cellulose fiber extremely useful in a wide variety of paper products requiring a combination of good strength in both wet and dry applications.
    Type: Grant
    Filed: May 27, 1994
    Date of Patent: June 4, 1996
    Assignee: Kimberly-Clark Corporation
    Inventor: Ramakant T. Shet
  • Patent number: 5520777
    Abstract: In manufacturing fiberboard, it is known to press mixtures of lignocellulosic material and binding agents to form a board product. In this invention, an improved process for manufacturing fiberboard is disclosed including the step of adding a solution of maleic anhydride and glycerol to the lignocellulosic material prior to refining thereof. The binder used is preferably phenolic-formaldehyde resin, in which case post-heating may be beneficial.
    Type: Grant
    Filed: September 2, 1994
    Date of Patent: May 28, 1996
    Assignee: Midnorth Forest Industry Alliance Inc.
    Inventor: Walter S. Shisko
  • Patent number: 5507914
    Abstract: A process for enhancing the freeness of paper pulp, which comprises the steps of adding to the pulp from about 0.5 to about 2.5 kilograms per ton based on the dry weight of the pulp, of a cellulolytic enzyme at the vertical tank of the papermaking process, allowing the pulp to contact the cellulolytic enzyme for from about 30 minutes to about 60 minutes, adding at least 0.011%, based on the dry weight of the pulp, of a water soluble cationic polymer, adding at least 0.007%, based on the dry weight of the pulp, of a water soluble anionic polymer and forming the thus treated pulp into paper.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: April 16, 1996
    Assignee: Nalco Chemical Company
    Inventors: Jawed M. Sarkar, Hanuman P. Didwania
  • Patent number: 5501768
    Abstract: The throughdryability of dewatered, but wet, sheets made from papermaking fibers can be significantly increased by subjecting an aqueous suspension of the fibers at high consistency to elevated temperatures with sufficient working of the fibers. Such a treatment is particularly effective for improving the efficiency of throughdrying processes used in the manufacture of certain products, such as tissues and paper towels, made from furnishes having a significant amount of secondary or recycled fibers.
    Type: Grant
    Filed: April 29, 1994
    Date of Patent: March 26, 1996
    Assignee: Kimberly-Clark Corporation
    Inventors: Michael A. Hermans, Robert J. Makolin, Kristin A. Goerg-Wood, Fung-jou Chen
  • Patent number: 5501770
    Abstract: A process for improving the freeness of paper pulp, which comprises the steps of adding to the pulp at least 0.05%, based on the dry weight of the pulp, of a cellulolytic enzyme, allowing the pulp to contact the cellulolytic enzyme for from about 40 minutes to about 60 minutes at a temperature of at least 40.degree. C., adding at least 0.011%, based on the dry weight of the pulp, of a water soluble cationic polymer, adding at least 0.007%, based on the dry weight of the pulp, of a water soluble anionic or nonionic polymer and forming the thus treated pulp into paper.
    Type: Grant
    Filed: August 12, 1994
    Date of Patent: March 26, 1996
    Assignee: Nalco Chemical Company
    Inventors: Jawed M. Sarkar, Hanuman P. Didwania
  • Patent number: 5487419
    Abstract: A process for the production of and a composition of redispersible mechanically disassembled cellulose and the resultant product, referred to as microdenominated cellulose (MDC). The process is characterized by drying the MDC in the presence of a dispersion agent. The product is characterized by a settled volume of greater than 50%, as determined on the basis of a 1% by weight suspension in water after twenty-four hours, and a water retention value of over 350%. MDC is useful as an ingredient in foods, pharmaceutical and cosmetic products.
    Type: Grant
    Filed: July 9, 1993
    Date of Patent: January 30, 1996
    Assignee: Microcell, Inc.
    Inventor: Michael K. Weibel
  • Patent number: 5476790
    Abstract: The fungi Schizophyllum commune, Trichaptum biforme and Phanerochaete gigantea are useful in reducing the pitch content of pulps and pulpwoods used in making cellulosic products.
    Type: Grant
    Filed: November 3, 1994
    Date of Patent: December 19, 1995
    Assignee: Sandoz Ltd.
    Inventors: Robert A. Blanchette, Roberta L. Farrell, Sara Iverson
  • Patent number: 5472874
    Abstract: The fungus Phlebia tremellosa is useful in reducing the pitch content of pulps and pulpwoods used in making cellulosic products.
    Type: Grant
    Filed: May 20, 1994
    Date of Patent: December 5, 1995
    Assignee: Sandoz Ltd.
    Inventors: Robert A. Blanchette, Roberta L. Farrell, Sara Iverson
  • Patent number: 5423946
    Abstract: A process for improving the freeness of paper pulp, which comprises the steps of adding to the pulp at least 0.05%, based on the dry weight of the pulp, of a cellulolytic enzyme, allowing the pulp to contact the cellulolytic enzyme for from about 40 minutes to about 60 minutes at a temperature of at least 40.degree. C., adding at least 0.011%, based on the dry weight of the pulp, of a water soluble cationic polymer, adding at least 0.007%, based on the dry weight of the pulp, of a water soluble anionic or nonionic polymer and forming the thus treated pulp into paper.
    Type: Grant
    Filed: March 7, 1994
    Date of Patent: June 13, 1995
    Assignee: Nalco Chemical Company
    Inventors: Jawed M. Sarkar, David R. Cosper
  • Patent number: 5413676
    Abstract: A cellulosic fiber of improved wettability comprising cellulosic fibers with small discrete crystal domain of ionic salt attached to the surface of the fiber. The method of making the cellulosic fiber of improved wettability is also claimed.
    Type: Grant
    Filed: September 30, 1993
    Date of Patent: May 9, 1995
    Assignee: Chicopee
    Inventors: Hien V. Nguyen, Cecilia Vargas
  • Patent number: 5407827
    Abstract: Bleaching pulp with an enzyme system, containing thermostatic xylanose activity, obtained from a strain of Thermomonospora fusca and more specifically from a new strain with the designation KW3 and deposition number DSM 6013.
    Type: Grant
    Filed: August 20, 1991
    Date of Patent: April 18, 1995
    Assignee: Sandoz Ltd.
    Inventors: Jutta Casimir-Schenkel, Susan Davis, Armin Fiechter, Beat Gysin, Elizabeth Murray, Jean-Jacques Perrolaz, Wolfgang Zimmermann
  • Patent number: 5399412
    Abstract: Uncreped throughdried basesheets can be made with the caliper of the basesheet being independent of the basis weight of the basesheet. Multi-ply wipers and towels produced by plying together two or more of such basesheets having a relatively low basis weight can provide products with improved caliper and absorbency for a given strength level and the amount of fiber used.
    Type: Grant
    Filed: May 21, 1993
    Date of Patent: March 21, 1995
    Assignee: Kimberly-Clark Corporation
    Inventors: Stephen J. Sudall, Steven A. Engel
  • Patent number: 5399240
    Abstract: The invention is a method of making a wet formed, sheeted, readily reslurriable sheeted crosslinked cellulose and the products made by the method. Crosslinked wood pulp fibers tend to be quite brittle. If crosslinked while in sheeted form, the sheets cannot be readily defibered, either in a wet or dry state, without serious fiber degradation. The sheet products of the present invention can be easily redispersed or repulped in water without significant fiber breakage. The present products are made by including within the sheet, while still in wet form, a debonding or softening agent which is preferably added before the latent crosslinking reactant. Most preferably the debonder is added prior to the headbox of a paper machine and the crosslinking reactant is applied near the end of the forming wire or at the press section. The treated sheet is dried conventionally. Crosslinking may occur entirely during drying or during a period of additional heating, usually at a temperature in excess of 100.degree. C.
    Type: Grant
    Filed: July 2, 1993
    Date of Patent: March 21, 1995
    Assignee: Weyerhaeuser Company
    Inventors: Peter A. Graef, Frank R. Hunter
  • Patent number: 5384012
    Abstract: An improved process for preparing crosslinked individualized cellulosic fibers wherein drying and curing are carried out in two separate stages while the fibers are entrained in turbulent pressurized superheated steam at elevated temperatures.
    Type: Grant
    Filed: March 26, 1993
    Date of Patent: January 24, 1995
    Assignee: James River Corporation of Virginia
    Inventor: Sherrill J. Hazard, Jr.
  • Patent number: 5384011
    Abstract: An improved process for preparing crosslinked individualized cellulosic fibers wherein drying and curing are carried out in two separate stages while the fibers are entrained in turbulent pressurized superheated steam at elevated temperatures.
    Type: Grant
    Filed: February 12, 1993
    Date of Patent: January 24, 1995
    Assignee: James River Corporation of Virginia
    Inventor: Sherrill J. Hazard, Jr.
  • Patent number: 5366591
    Abstract: A method of forming a crosslinked cellulose product is disclosed wherein cellulose fibers are exposed to a solution that includes a catalyst and a crosslinking agent selected from the group consisting of a cyclic N-sulfatoimide or cyclic N-phosphatoimide; a dimethoxyethanal; a mixture of glyoxal and imidazolidone; a diethanol; or a periodate. Specific examples of the crosslinking agents of the present invention include pyridinium N-sulfatosuccinimide; 2,2'-sulfonyldiethanol; sodium periodate; a mixture of dimethoxyethanal and urea; and a mixture of glyoxal and 2-imidazolidone. An acid or base catalyst, as appropriate, may be used with the crosslinking agent to increase the crosslinking reaction rate. In especially preferred embodiments, cellulose fibers are exposed to the crosslinking agent and catalyst, then separated into individualized fibers in a fiberizer.
    Type: Grant
    Filed: January 13, 1992
    Date of Patent: November 22, 1994
    Inventor: Richard A. Jewell
  • Patent number: 5348620
    Abstract: The throughdryability of dewatered, but wet, sheets made from papermaking fibers can be significantly increased by subjecting an aqueous suspension of the fibers at high consistency to elevated temperatures with sufficient working of the fibers. Such a treatment is particularly effective for improving the efficiency of throughdrying processes used in the manufacture of certain products, such as tissues and paper towels, made from furnishes having a significant amount of secondary or recycled fibers.
    Type: Grant
    Filed: December 18, 1992
    Date of Patent: September 20, 1994
    Assignee: Kimberly-Clark Corporation
    Inventors: Michael A. Hermans, Robert J. Makolin, Kristin A. Goerg, Fung-Jou Chen
  • Patent number: 5324391
    Abstract: A method is disclosed for preparing a quantity of individual treated fibers from one or more fiber mats in a treatment apparatus. The apparatus comprises a fiber treatment zone, a conveyor for conveying each mat through the fiber treatment zone, wherein each mat is impregnated by an applicator with a crosslinking substance, and directly to an attrition device. The attrition device fiberizes the mats to form a fiber output having a low nit level, such as no more than about three, and a dryer for both drying the fiber output and curing the crosslinking substance. The fiberizer is configured to have minimize the accumulation of fiber at locations therein. An optional component of the fiberizer is a novel fluff generator comprised of multiple rotors each having plural longitudinally extended rows of radially extending rotor pins that rotate past groups of shorter pins mounted on the inside surface of the fluff generator housing.
    Type: Grant
    Filed: November 9, 1992
    Date of Patent: June 28, 1994
    Assignee: Weyerhaeuser Company
    Inventors: Allan R. Carney, Peter A. Graef, Mark W. Bowns, Clifford R. Bolstad, Fred E. Olmstead
  • Patent number: 5314582
    Abstract: A cellulosic fiber of improved wettability comprising cellulosic fibers with small discrete crystal domain of ionic salt attached to the surface of the fiber. The method of making the cellulosic fiber of improved wettability is also claimed.
    Type: Grant
    Filed: July 22, 1992
    Date of Patent: May 24, 1994
    Assignee: Chicopee
    Inventors: Hien V. Nguyen, Cecilia Vargas
  • Patent number: 5275699
    Abstract: There is disclosed a filled cellulosic fiber composition, as well as a method for filling dried cellulosic fibers with an inorganic filler by contacting the dried fibers with a first salt solution, followed by contact with a second salt solution. The first and second salt solutions combine to form a precipitate within the cell wall of the cellulosic fibers. The filled cellulosic fiber composition may be made into a variety of paper products, including paper, having a high filler content. The precipitates of the present invention include carbonates, phosphates, silicates and borates of aluminum, barium, calcium, magnesium and zinc. The first salts include carbonates, phosphates, silicates and borates of sodium, ammonium, potassium and lithium, and the second salts include chlorides, nitrates, and sulfates of aluminum, barium, calcium, magnesium and zinc.
    Type: Grant
    Filed: October 7, 1992
    Date of Patent: January 4, 1994
    Assignee: University of Washington
    Inventors: G. Graham Allan, John P. Carroll
  • Patent number: 5225047
    Abstract: The invention is a method of making a wet formed, sheeted, readily reslurriable sheeted crosslinked cellulose and the products made by the method. Crosslinked wood pulp fibers tend to be quite brittle. If crosslinked while in sheeted form, the sheets cannot be readily defibered, either in a wet or dry state, without serious fiber degradation. The sheet products of the present invention can be easily redispersed or repulped in water without significant fiber breakage. The present products are made by including within the sheet, while still in wet form, a debonding or softening agent which is preferably added before the latent crosslinking reactant. Most preferably the debonder is added prior to the headbox of a paper machine and the crosslinking reactant is applied near the end of the forming wire or at the press section. The treated sheet is dried conventionally. Crosslinking may occur entirely during drying or during a period of additional heating, usually at a temperature in excess of 100.degree. C.
    Type: Grant
    Filed: August 17, 1989
    Date of Patent: July 6, 1993
    Assignee: Weyerhaeuser Company
    Inventors: Peter A. Graef, Frank R. Hunter
  • Patent number: RE35460
    Abstract: The present invention relates to a method for loading a chemical compound within the fibers of a fibrous material and to the fibrous materials produced by the method. In the method, a fibrous cellulose material is provided which consists of a plurality of elongated fibers having a fiber wall surrounding a hollow interior. The fibrous material has a moisture content such that the level of water ranges from 40-95% of the weight of the fibrous material and the water is positioned substantially within the hollow interior of the fibers and within the fiber walls of the fibers. A chemical is added to the fibrous material in a manner such that the chemical is disposed in the water present in the fibrous material. The fibrous material is then contacted with a gas which is reactive with the chemical to form a water insoluble chemical compound. The method provides a fibrous material having a chemical compound loaded within the hollow interiors and within the fiber walls of the plurality of fibers.
    Type: Grant
    Filed: October 21, 1993
    Date of Patent: February 25, 1997
    Assignee: The United States of America as represented by the Secretary of Agriculture
    Inventors: John H. Klungness, Daniel F. Caulfield, Irving B. Sachs, Marguerite S. Sykes, Freya Tan, Richard W. Shilts