Pitch Control Patents (Class 162/DIG4)
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Patent number: 5286347Abstract: A method for inhibiting the deposition of pitch on and/or for removing pitch from the surfaces of pulping and papermaking machinery by adding an effective amount of a melamine formaldehyde-type polymer to a pulp slurry or furnish in contact with said machinery.Type: GrantFiled: May 5, 1992Date of Patent: February 15, 1994Assignee: Calgon CorporationInventor: Paul F. Richardson
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Patent number: 5266166Abstract: Methods for inhibiting deposition of organic contaminants from pulp in pulp and papermaking systems which comprises treating the pulp and papermaking system with an effective amount of a polyalkylene oxide/vinyl acetate graft copolymer.Type: GrantFiled: May 18, 1992Date of Patent: November 30, 1993Assignee: Betz PaperChem, Inc.Inventors: David D. Dreisbach, Iris D. Barton
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Patent number: 5256254Abstract: The present invention is directed to the use of phosphate esters or taurines to inhibit dryer section deposition in a pulp making or paper machine when the pulp furnish used contains tacky materials. The deposition control agent may be added to the pulp furnish or sprayed on the paper web. The phosphate ester may be a mono-, di- or triester.Type: GrantFiled: July 12, 1991Date of Patent: October 26, 1993Assignee: Betz PaperChem, Inc.Inventors: Jacqueline K. Pease, Dennis W. Barton, Glenn J. Henderson
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Patent number: 5256252Abstract: A method of controlling pitch deposits in a pulp and papermaking process comprising adding lipase and a cationic polymer to a cellulosic slurry in amounts effective for diminishing pitch deposits from the cellulosic slurry in a pulp and/or paper mill. The method may include adding lipase and a cationic polymer to a cellulosic slurry in amounts effective for both reducing the triglyceride content of a cellulosic slurry by hydrolysis and diminishing the concentration of fatty acids released by the hydrolysis in the aqueous phase of a cellulosic slurry. The triglyceride hydrolysate content of the aqueous phase of a cellulosic slurry, formed by the action of lipase on triglyceride within the cellulosic slurry, is reduced when the amount of lipase and the amount of a cationic polymer is maintained for a time period sufficient to hydrolyze at least some of the triglyceride in the cellulosic slurry and reduce the triglyceride hydrolysate in the aqueous phase of the cellulosic slurry.Type: GrantFiled: July 15, 1992Date of Patent: October 26, 1993Assignee: Nalco Chemical CompanyInventors: Jawed M. Sarkar, Martha R. Finck
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Patent number: 5246547Abstract: A method for controlling pitch in papermaking systems which comprises the step of adding a hydrophobic polyelectrolyte copolymer coagulant to pulp and paper process water. The hydrophobic polyelectrolyte copolymer coagulant comprises diallyldimethylammonium chloride and a hydrophobic monomer selected from the group consisting of: quaternized dimethylaminoethylacrylates and quaternized dimethylaminoethylmethacrylates.Type: GrantFiled: July 14, 1992Date of Patent: September 21, 1993Assignee: Nalco Chemical CompanyInventors: Martha R. Finck, Carol S. Greer, Manian Ramesh
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Patent number: 5246548Abstract: A method for the control of pitch in paper making machine dryer fabrics or equipment which are not in continuous contact with process water comprising applying to the fabrics or equipment, a water-soluble or water-dispersible cationic polymer and a water-soluble or water dispersible anionic aromatic polymer.Type: GrantFiled: October 28, 1992Date of Patent: September 21, 1993Assignee: Dearborn Chemical Company LimitedInventors: David A. Aston, John K. Hochu
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Patent number: 5230774Abstract: Pitch control agents comprising a combination of water-soluble zirconium compounds and cationic polymers are described.Ammonium zirconium carbonate is preferred in combination with poly DADMAC and/or with EPI-DMA polymers.Type: GrantFiled: September 3, 1991Date of Patent: July 27, 1993Assignee: Nalco Chemical CompanyInventors: Carol S. Greer, Nancy P. James
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Patent number: 5223097Abstract: A method for the control of pitch in an aqueous system used in pulp or paper making is disclosed which comprises adding to the system, or to the pulp making or paper making machinery, a water soluble polymer derived from (a) an epihalohydrin, a diepoxide or a precursor of an epihalohydrin or diepoxide, (b) an alkyl amine having a functionality with respect to an epihalohydrin of 2 and (c) an amine which has a functionality with respect to an epihalohydrin greater than 2 and which does not possess any carbonyl groups.Type: GrantFiled: June 20, 1989Date of Patent: June 29, 1993Assignee: W. R. Grace ABInventor: Thord G. G. Hassler
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Patent number: 5221436Abstract: There is disclosed a process for controlling the deposition of pitch in a paper-making process, wherein there is incorporated into the paper-making composition a coated inorganic particulate material which comprises a clay mineral coated with (a) a cationic polyelectrolyte which is a water-soluble substituted polyolefin containing quaternary ammonium groups or with (b) an inorganic gel or with (c) a mixture of (a) and (b).Type: GrantFiled: November 28, 1990Date of Patent: June 22, 1993Assignee: ECC International LimitedInventors: Keith R. Rogan, John M. Adams
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Patent number: 5213661Abstract: A method is disclosed for the detackification of stickies in the production of recycled paper products containing secondary fibers. Oxygen is used to reduce the tackiness of stickies in secondary pulps, and optionally is used with alkali and/or detackification agents for optimum stickies control. The preferred alkali source is fully oxidized white liquor.Type: GrantFiled: May 21, 1991Date of Patent: May 25, 1993Assignee: Air Products and Chemicals, Inc.Inventors: Ronald C. Naddeo, Konstantinos Hristofas, Vincent L. Magnotta
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Patent number: 5176796Abstract: The method for avoiding pitch troubles includes the treatment with an acylglycerol lipase. The method of the present invention overcomes the pitch troubles in a process for the production of mechanical pulp and/or mechanical pulp-containing paper.Type: GrantFiled: April 15, 1991Date of Patent: January 5, 1993Assignee: Jujo Paper Co., Ltd.Inventors: Yuko Irie, Motoo Matsukura, Kunio Hata
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Patent number: 5167767Abstract: This invention relates to an improved press felt conditioning treatment which controls the deposition of polymerically flocculated particulate substances in a press felt. The treatment comprises applying to the felt an effective inhibiting amount of a conditioner comprising a combination of a polymethylnaphthalene sulfonate and a type A phosphate ester comprising a nonyl phenol hydrophobe based phosphate ester having between 6 and 10 moles of ethylene oxide and a mono to diester ratio of approximately 60 to 40 or a type B phosphate ester comprising a tridecyl alcohol hydrophobe based phosphate ester having between 6 and 10 moles of ethylene oxide and a mono to diester ratio of about 60 to 40. The use of this combination was found to be especially effective at preventing the deposition of polymerically flocculated particulate substances in a press felt and paper machine.Type: GrantFiled: March 25, 1991Date of Patent: December 1, 1992Assignee: Betz PaperChem, Inc.Inventors: Clarice A. Owiti, Abdul Q. Khan
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Patent number: 5135613Abstract: Pitch formation in a paper mill is controlled by a chemical composition of a water-soluble polymer of polycyanoguanidineammoniumchloride (PGAC) or polycyanoguanidineureaammoniumchloride (PGUAC).Type: GrantFiled: February 4, 1991Date of Patent: August 4, 1992Assignee: Maxichem, Inc.Inventor: John J. Waldmann
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Patent number: 5131982Abstract: DADMAC containing polymers, both homopolymers and copolymers are used in effective coagulating amounts to treat cellulosic fibres recycled from coated broke recovery. The DADMAC containing polymers are either homopolymers or are preferably copolymers containing acrylamide. Recycle of coated broke can cause difficulties when the fibres are recycled to the paper manufacturing process because the coatings contain binders which cause what is referred to as "white pitch", the accumulation of which can cause holes in the paper, build-up of residues and sticky masses, and clogging of felts and the like in the manufacture of paper. The use of the DADMAC polymers eliminates this difficulty in making paper from recycled cellulose fibres ottained from coated broke recycle.Type: GrantFiled: February 26, 1990Date of Patent: July 21, 1992Assignee: Nalco Chemical CompanyInventor: Michael R. St. John
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Patent number: 5080759Abstract: The deposition of stickies on machinery used in the pulping and papermaking processes and in the final paper produced in the papermaking process using secondary or recycled paper is controlled by adding an amount of a water-soluble organotitnium(IV) compound to the aqueous system of a pulping and/or papermaking process, effective to reduce or remove the deposition of the stickies on the machinery and the resulting paper.Type: GrantFiled: September 4, 1990Date of Patent: January 14, 1992Assignee: Quaker Chemical CorporationInventors: John H. Buzby, Robert D. Evans
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Patent number: 5074961Abstract: The invention is a process for controlling pitch deposition from pulp in papermaking systems, by an effective amount of a polymer having methyl ether groups pendant to the backbone of the polymer to the pulp term "polymer". A preferred embodiment of the invention is controlling pitch deposition by adding an effective amount of a water soluble cellulose ether.Type: GrantFiled: July 17, 1989Date of Patent: December 24, 1991Assignee: Betz Laboratories, Inc.Inventors: David D. Dreisbach, Gilbert S. Gomes
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Patent number: 5074958Abstract: A process for removing stickies and/or PCDD's and PCDF's from cellulose-containing fibers such as waste paper is provided. The process comprises contacting the fibers with supercritical or near supercritical propane for a period of time sufficient to extract a substantial portion of the stickies and/or PCDD's and PCDF's without substantially damaging the fibers. Extraction efficiencies of up to 95% for PCDD's or PCDF's and of about 70% to 95% for stickies have been achieved with the technique.Type: GrantFiled: April 15, 1991Date of Patent: December 24, 1991Assignee: Kimberly-Clark CorporationInventors: Carol A. Blaney, Shafi U. Hossain
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Patent number: 5073235Abstract: A process for improving the life of papermaking belts containing a cured photosensitive polymeric resin is disclosed. The process includes the continuous application of an effective amount of chemical compounds capable of slowing down the degradation rate of the photosensitive polymeric resin to the belt's surface during the papermaking operation. Preferably, the chemical compounds are antioxidants which inhibit or retard oxidation of the cured resin and its ensuing degradative effects.Type: GrantFiled: April 12, 1990Date of Patent: December 17, 1991Assignee: The Procter & Gamble CompanyInventor: Paul D. Trokhan
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Patent number: 5037508Abstract: Kaolin clay treated with 0.5 to 1.5 wt. % of aluminum chlorohydrate or a double hydroxide of aluminum and magnesium are an effective pitch adsorption agent for use in paper making processes.Type: GrantFiled: March 29, 1990Date of Patent: August 6, 1991Assignee: J. M. Huber CorporationInventors: Walter J. Hyder, Albert C. Kunkle, Robert M. Weaver
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Patent number: 5009746Abstract: A process for removing sticky contaminants ("stickies") from cellulose-containing fibers such as waste paper is provided. The process comprises contacting the fibers with supercritical or near supercritical carbon dioxide for a period of time sufficient to extract a substantial portion of the stickies without substantially damaging the fibers.Type: GrantFiled: October 12, 1990Date of Patent: April 23, 1991Assignee: Kimberly-Clark CorporationInventors: Shafi U. Hossain, Carol A. Blaney
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Patent number: 4997523Abstract: A composition and method for inhibiting the deposition of white pitch on the surfaces of papermaking equipment during the processing of recycled coated broke. The process involves adding to the coated broke during repulping a composition having a first compound of a tetrafunctional alkoxylated diamine having the structure: ##STR1## wherein R.sub.1 and R.sub.2 are ethylene oxide or propylene oxide and R.sub.1 and R.sub.2 are not the same, and a second compound selected from the group consisting of a phosphate, phosphonate and phosphonic acid.Type: GrantFiled: June 20, 1990Date of Patent: March 5, 1991Assignee: Betz PanerChem, Inc.Inventors: Jacqueline K. Pease, Catherine S. Dixon, Daniel L. Michalopoulos
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Patent number: 4995944Abstract: A method is disclosed for treating papermill felts to inhibit the deposit of sticky material thereon. The method comprises applying an aqueous solution which contains at least about 2 ppm of a cationic polymer; which contains a water soluble cationic surfactant; the surfactant being applied in an amount effective to inhibit build-up of deposits derived from the cationic polymer. Cationic surfactants are preferred. Particular use is disclosed of water soluble surfactants which have a molecular weight between about 200 and 800 and having the general formula: ##STR1## wherein each R is independently selected from the group consisting of hydrogen, polyethylene oxide groups, polypropylene oxide groups, alkyl groups having between about 1 and 22 carbon atoms, aryl groups, and aralkyl groups, at least one of said R groups being an alkyl group having at least about 8 carbon atoms, and wherein X.sup.- is an anion, or 1/n of an n-valent anion.Type: GrantFiled: August 9, 1990Date of Patent: February 26, 1991Assignee: Dearborn Chemical Company Ltd.Inventors: David A. Aston, Stewart N. Paul
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Patent number: 4985120Abstract: The deposition of pitch on the machinery used in pulping and papermaking processes and in the final paper produced in the papermaking process is prevented by adding an effective amount of a water-soluble organotitanium compound to the aqueous system of a pulping and/or papermaking process to prevent the deposition of the pitch on the machinery and in the final paper. The addition of an effective amount of a water-soluble organotitanium compound to the aqueous system of pulping and papermaking processes also removes pitch deposits from the machinery used in the pulping and papermaking processes.Type: GrantFiled: August 17, 1990Date of Patent: January 15, 1991Assignee: Quaker Chemical CorporationInventors: John H. Buzby, Robert D. Evans
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Patent number: 4964952Abstract: A method of controlling pitch in an aqueous system involved in paper making as described which comprises adding a cationically modified tannin to the system.Type: GrantFiled: April 28, 1988Date of Patent: October 23, 1990Assignee: W. R. Grace & Co.-Conn.Inventors: John J. Bennison, Richard P. Clifford
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Patent number: 4964955Abstract: A method of and substances for reducing pitch in pulping and papermaking operations, particularly in furnishes made by mechanical pulping processes containing wood pulp in amounts greater than about 10% by weight, are disclosed. The method comprises adding to a pitch-containing furnish a stable, water dispersible particulate composite substance prepared by irreversibly adsorbing a water soluble cationic polymer, e.g., a poly(diallyldimethylammonium chloride), onto an essentially water insoluble particulate substrate, e.g., kaolin, thereby rendering the cationic polymer insoluble and immobile, the cationic polymer being sufficiently electropositive so that the particulate composite pitch control substance exhibits a zeta potential of at least about +30 mV, and preferably from about +60 mV to about +80 mV, the amount of the composite substance added to the furnish being effective to finely disperse pitch for removal as finely-dispersed pitch-containing aggregates in a paper sheet produced from said furnish.Type: GrantFiled: December 21, 1988Date of Patent: October 23, 1990Assignee: Cyprus Mines CorporationInventors: Richard S. Lamar, William E. Pratt, Kenneth E. Weber, Robert E. Roeder
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Patent number: 4956119Abstract: The present invention involves new anti-foam compositions which control foaming in aqueous systems and by nature of their unique cloud point characteristics are insoluble and particulate above their inverse cloud point, and soluble below it. This property makes them particulate non-depositing defoamers. As the defoamed aqueous system cools down these novel products become soluble, preventing insoluble material (pitch) from depositing on process equipment and matter being processed.Type: GrantFiled: April 20, 1989Date of Patent: September 11, 1990Inventors: Thomas C. Friel, Jr., Anthony J. O'Lenick, Jr.
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Patent number: 4956051Abstract: The present invention involves the use of a polymeric material comprised of polyvinyl alcohol moieties to control the depositing tendency of adhesive materials contained in waste paper and paper products which are being utilized to produce finished paper products. The polyvinyl alcohol is added to the water sprays or showers used on the felts, wires, and press rolls.Type: GrantFiled: July 27, 1989Date of Patent: September 11, 1990Assignee: Betz PaperChem, Inc.Inventor: Robert D. Moreland
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Patent number: 4950361Abstract: The deposition of pitch on the machinery used in the pulping and papermaking processes and in the final paper produced in the papermaking process is prevented by adding an effective amount of a water-soluble zirconium(IV) compound to the aqueous system of a pulping and/or papermaking process to prevent the deposition of pitch on the machinery and in the final paper. The addition of an effective amount of a water-soluble zirconium(IV) compound to the aqueous system of the pulping and papermaking process also removes pitch deposits from the machinery used in the pulping and papermaking processes.Type: GrantFiled: September 15, 1988Date of Patent: August 21, 1990Assignee: Quaker Chemical CorporationInventors: Gregory W. Bender, Stan D. Buratto, Robert D. Evans
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Patent number: 4927465Abstract: Kaolin clay treated with 0.5 to 1.5 wt. % of aluminum chlorohydrate or a double hydroxide of aluminum and magnesium are an effective pitch adsorption agent for use in paper making processes.Type: GrantFiled: October 19, 1987Date of Patent: May 22, 1990Assignee: J. M. Huber CorporationInventors: Walter J. Hyder, Albert C. Kunkle, Robert M. Weaver
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Patent number: 4923566Abstract: Urea is used to pacify "stickies" in the manufacture of paper products, particularly coated boxboard.Type: GrantFiled: April 26, 1989Date of Patent: May 8, 1990Assignee: Nalco Chemical CompanyInventors: Shamel M. Shawki, Richard N. Van Oss
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Patent number: 4906383Abstract: This invention relates to novel polymeric compositions which are useful for water treatment. These novel compositions are comprised of polymers of .alpha., .beta. ethylenically unsaturated monomer(s), preferably containing carboxylic acid or carboxylic amide functionalities, and amine-containing allyl ether monomers.Type: GrantFiled: July 5, 1988Date of Patent: March 6, 1990Assignee: Betz Laboratories, Inc.Inventors: Fu Chen, William S. Carey
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Patent number: 4895622Abstract: This invention relates to an improved press felt conditioning treatment which controls the deposition of polymerically flocculated particulate substances in a press felt. The treatment comprises applying to the felt an effective inhibiting amount of a conditioner comprising a relatively low molecular weight organic, anionic polymer and at least one hydrophilic, nonionic or anionic surfactant. The polymer preferrably has an acrylic acid or methacrylic acid functionality and is preferrably selected from the group consisting of homopolymers of acrylic acid, a methacrylic acid/polyethylene glycol allyl ether copolymer, a homopolymer of methacrylic acid, an acrylic acid/polyethylene glycol allyl ether copolymer, and an acrylic acid/1-allyloxy-2-hydroxypropane sulfonic acid copolymer.Type: GrantFiled: November 9, 1988Date of Patent: January 23, 1990Assignee: Betz Laboratories, Inc.Inventors: Daniel J. Barnett, Abdul Q. Khan, Patricia R. Keen
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Patent number: 4886575Abstract: The invention is directed to the use of polyvinyl alcohol to control the problem of "stickies" in waste paper processing.Type: GrantFiled: October 8, 1985Date of Patent: December 12, 1989Assignee: Betz Laboratories, Inc.Inventor: Robert D. Moreland
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Patent number: 4871424Abstract: The invention relates to a process for controlling pitch deposition from pulp in papermaking systems which comprises adding to the pulp an effective amount of a polymer having hydroxyl groups pendant to the backbone of the polymer. The polymer can be polyvinyl alcohol having 50% to 100% hydrolysis. The polymer can also be a water-soluble copolymer having recurring units of nonionic hydrophilic monomers, and/or hydrophobic monomers, wherein the copolymer has at least 20 mol percent of vinyl alcohol. In another aspect, this invention comprises adding to the pulp an effective amount of a water-soluble polymer derived by substituting hydroxyl groups onto a preformed reactive polymer, wherein the water-soluble polymer has at least 20 mol percent of hydroxyl groups.Type: GrantFiled: June 7, 1988Date of Patent: October 3, 1989Assignee: Betz Laboratories, Inc.Inventors: David D. Dreisbach, Gilbert S. Gomes
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Patent number: 4861429Abstract: This invention relates to a process for inhibiting white pitch deposition in felts of a papermaking system including adding to the felts an effective inhibiting amount of an organic, anionic polyelectrolyte. The molecular weight of the polyelectrolyte is preferably from about 1,000 to 100,000. The polyelectrolyte is selected from the group consisting of polyacrylic acid, polmethacrylic acid, acrylic acid/polyethylene glycol allyl ether copolymers, methacrylic acid/polyethylene glycol allyl ether copolymers, acrylic acid/1-allyloxy-2-hydroxypropane sulfonic acid copolymers. The use of these polyelectrolytes in combination with surfactants provides an especially effective white pitch inhibiting and total felt conditioning process when applied to the felt.Type: GrantFiled: July 29, 1988Date of Patent: August 29, 1989Assignee: Betz Laboratories, Inc.Inventors: Daniel J. Barnett, Daniel L. Michalopoulos
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Patent number: 4846933Abstract: A process for controlling pitch deposition from pulp in papermaking systems which comprises adding to the pulp an effective amount of a polymer containing polymerized units of methyl vinyl ether.Type: GrantFiled: February 17, 1988Date of Patent: July 11, 1989Assignee: Betz Laboratories, Inc.Inventors: David D. Dreisbach, Gilbert S. Gomes
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Patent number: 4765867Abstract: The invention relates to a process for controlling pitch deposition from pulp in papermaking systems which comprises adding to the pulp an effective amount of a water-soluble quaternized polyamine ionene polymer.Type: GrantFiled: July 2, 1986Date of Patent: August 23, 1988Assignee: Betz Laboratories, Inc.Inventors: David D. Dreisbach, Gilbert S. Gomes, Michael A. Schuster
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Patent number: 4744865Abstract: The invention relates to a process for controlling pitch deposition from pulp in papermaking systems which comprises adding to the pulp an effective amount of a polymer having methyl ether groups pendant to the backbone of the polymer.Type: GrantFiled: June 3, 1986Date of Patent: May 17, 1988Assignee: Betz Laboratories, Inc.Inventors: David D. Dreisbach, Gilbert S. Gomes
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Patent number: 4673460Abstract: An improved method for deresination of wood chips or pulp is provided. The method comprises contacting the chips or pulp with an ethoxylated alkyl phenol deresinating composition during processing to reduce the level of natural resins present therein. The improvement comprises substituting a sufonated fatty acid for part of the ethoxylated alkyl phenol while maintaining substantially the same level of deresination.Type: GrantFiled: September 27, 1984Date of Patent: June 16, 1987Assignee: Stepan CompanyInventor: Donald K. Raff
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Patent number: 4652377Abstract: Inhibition of sulfate scale precipitation in a water system is accomplished by adding to said water system an effective threshold inhibition amount of a polyacrylic acid, phytic acid, and a phosphonocarboxylic acid containing at least one phosphono group, at least two carboxylic groups, and a hydrocarbon chain of at least two carbon atoms. The active materials are used in the ratio of 0.1 to 30 parts polyacrylic acid and 0.1 to 30 parts phosphonocarboxylic acid per one weight part of phytic acid.Type: GrantFiled: August 20, 1985Date of Patent: March 24, 1987Assignee: The BF Goodrich CompanyInventor: Zahid Amjad
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Patent number: 4608123Abstract: Disclosed is a method of minimizing the untoward effect of contaminants, such as pitch and related materials, in the papermaking operation. An aqueous dispersion of water-dispersible synthetic pulp, such as polypolyolefin pulp, is added to a pulp slurry comprised of cellulosic pulp, at a point prior to sheet formation. The synthetic pulp adsorbs a substantial amount of the pitch present in the pump slurry and prevents it from depositing on the papermaking apparatus.Type: GrantFiled: February 20, 1985Date of Patent: August 26, 1986Assignee: Hercules IncorporatedInventor: Robert J. Leahy
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Patent number: 4313790Abstract: A process is disclosed for the production of paper and paper-like products which consists of the addition to the papermaking furnish of kraft lignin or modified kraft lignin and poly(oxyethylene).Type: GrantFiled: March 31, 1980Date of Patent: February 2, 1982Assignee: Pulp and Paper Research Institute of CanadaInventors: Robert H. Pelton, Lawrence H. Allen, Henry M. Nugent
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Patent number: 4190491Abstract: A process for preventing deposition of pitch in papermaking comprising incorporating in a paper pulp slurry a water-soluble linear cationic polymer comprised of units of the formula ##STR1## wherein A is a (C.sub.2 -C.sub.3) alkylene group,R is H or CH.sub.3 ;R.sup.1 is a hydroxyethyl or hydroxypropyl group,R.sup.2 is a (C.sub.1 -C.sub.4) alkyl group,R.sup.3 is a (C.sub.1 -C.sub.4) alkyl group, andX is an anion;said polymer having a viscosity average molecular weight of about 35,000 to 70,000.Type: GrantFiled: August 24, 1978Date of Patent: February 26, 1980Assignee: Rohm and Haas CompanyInventors: Thomas J. Drennen, Robert A. Gill
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Patent number: 4184912Abstract: Pitch formation in paper mill pulp systems may be inhibited by treating such systems, at a point prior to where pitch deposits normally occur, with at least 0.Type: GrantFiled: November 17, 1978Date of Patent: January 22, 1980Assignee: Nalco Chemical CompanyInventor: James H. Payton
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Patent number: 4100067Abstract: Valuable amino alkane diphosphonic acids in which one or both hydrogen atoms of the amino group are substituted by hydroxy alkane groups, and their alkali metal salts and a process of using them are described. Said compounds are highly water-soluble, are stable against hydrolysis even at temperatures exceeding 100.degree. C., and have a high sequestering power so that they can be used advantageously, for instance, in processing aqueous media of considerable hardness, and in suppressing scale and corrosion in aqueous media used for heat treatment of containers.Type: GrantFiled: January 18, 1977Date of Patent: July 11, 1978Assignee: Benckiser-Knapsack GmbH.Inventors: Klaus Sommer, Guenter Raab
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Patent number: 4010067Abstract: The difficulties encountered in the manufacture of paper, cardboard, and other cellulosic articles, as they are caused by the formation of resinous or pitch deposits on the paper as well as on the paper machines and processing apparatus, are overcome or at least considerably reduced, by the addition of phosphonic acids and more particularly of alkyl, amino or hydroxy alkyl, or cycloalkyl phosphonic acids or their alkali metal salts and of orthophosphoric acid or its alkali metal salts and/or of polyphosphoric acids. If required, amino polycarboxylic acids, hydroxy carboxylic acids, or their alkali metal salts, or alkali metal polyphosphates are also added during processing.Type: GrantFiled: February 21, 1975Date of Patent: March 1, 1977Assignee: Benckiser-Knapsack GmbHInventors: Ernst Hoeger, Margarete Scholl
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Patent number: 3992249Abstract: The deposition of adhesive pitch particles from aqueous suspension of cellulose fibers is inhibited and, if desired, substantially prevented, from depositing on the surfaces of pulp-making equipment by adding to the suspension an anionic polymer containing at least about 25 mol percent but not more than about 85 mol percent of hydrophobic oleophilic linkages selected from the group comprising styrene, isobutylene, methylstyrene, allyl stearate, octadecyl acrylate, octadecene, dodecene, n-octadecylacrylamide, vinyl stearate and vinyl dodecyl ether and at least about 15 mol percent but not more than about 75 mol percent of hydrophilic acid linkages selected from the group comprising acrylic acid, methacrylic acid, maleic acid, itaconic acid, acrylamidoacetic acid, maleamic acid and styrenesulfonic acid, forming a pitch-polymer complex of said particles and said polymer, and removing said complex with the water used to wash said cellulose fiber suspension thereby separating substantially all of the pitch-polymerType: GrantFiled: December 8, 1975Date of Patent: November 16, 1976Assignee: American Cyanamid CompanyInventor: Charles Edward Farley