Patents Assigned to EKA Chemicals AB
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Patent number: 9156990Abstract: The present invention relates to a filler comprising calcium salt and cellulose derivative having a degree of substitution of net ionic groups up to about 0.65, wherein the filler is substantially free from fibers or fibrils of cellulose or lignocellulose. The invention also relates to a filler comprising calcium salt and a cellulose derivative having a degree of substitution of net ionic groups up to about 0.65, wherein the cellulose derivative contains cationic groups.Type: GrantFiled: December 21, 2004Date of Patent: October 13, 2015Assignee: EKA CHEMICALS ABInventors: Peter Marten Van Der Horst, Erik Sanne, Kjell Rune Andersson, Cherryleen Garcia-Lindgren, Marie-Louise Wallberg, Sune Wännström
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Patent number: 7825240Abstract: There are described novel cross-linked polymers based on bis-silane, bis-thioether, bis-sulphoxide, bis-sulphone and butane-di-yl derivatives of polysaccharides and oligosaccharides, their shaping as support materials useful for the separation or preparation of enantiomers; a process for preparing the said cross-linked polymer compounds, a process for preparing balls of support materials containing the said cross-linked polymer compounds; a method of obtaining balls of support materials useful in chromatography or in organic synthesis; and the use of the said support materials containing the cross-linked polymer compounds in separation or in preparation of enantiomers, through employment in chromatography or organic synthesis processes in a heterogeneous medium; and the use of the said cross-linked polymer compounds in the form of membranes in processes using percolation through membranes for the separation or the preparation of enantiomers.Type: GrantFiled: October 29, 2003Date of Patent: November 2, 2010Assignee: Eka Chemicals ABInventor: Raphaël Duval
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Patent number: 7576034Abstract: The invention concerns a crosslinked optically active three-dimensional polymer network, consisting of homochiral units of a first selector and of homochiral units of at least a second selector of different structure from the first selector, the homochiral units of the first selector comprising at least three polymerisable or crosslinkable functional groups and the homochiral units of the second selector comprising at least two polymerisable or crosslinkable functional groups, the homochiral groups being chemically mutually bound. The invention also concerns a method for making such a polymer network and its uses.Type: GrantFiled: September 23, 2002Date of Patent: August 18, 2009Assignee: Eka Chemicals ABInventors: Raphaël Duval, Hubert Leveque
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Patent number: 7067640Abstract: The invention relates to a method which comprises synthesizing bifunctional compounds then chiral compounds from the bifunctional compounds, also to synthesizing supports comprising these chiral compounds, and the use of these supports for preparing or separating enantiomers, or for asymmetric synthesis. The invention also relates to bifunctional compounds, their use as a source of functionalized polymers, and to the chiral compounds, also to the use of these chiral compounds in a chiral support in the form of a three-dimensional network or for separating or preparing enantiomers, principally for analytical or preparative chromatography, and in a support for the production of chiral molecules by asymmetric synthesis.Type: GrantFiled: April 3, 2000Date of Patent: June 27, 2006Assignee: EKA Chemicals ABInventors: Raphaël Duval, Hubert Leveque
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Patent number: 6255272Abstract: The invention relates to particles comprising a peroxy compound with capability of realeasing hydrogen peroxide or peroxy acids in aqueous solutions and an amino acid of the formula (HOOC)2N—CnHmCOOH—R in which R is H, CH2OH OR CH3, n is 1, 2 or 3 and m is 0-2n; or a salt thereof. The invention also relates to use of the particles and a composition comprising such particles.Type: GrantFiled: April 5, 2000Date of Patent: July 3, 2001Assignee: Eka Chemicals ABInventors: Hans Lagnemo, Monica Jigstam
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Patent number: 6174383Abstract: The invention relates to a method at pickling of steel in an acidic aqueous pickling solution containing Fe3+ and Fe2+, wherein the steel is contacted with pickling solution that continuously is brought to circulate through a conduit into which hydrogen peroxide is supplied to oxidize Fe2+ to Fe3+.Type: GrantFiled: July 1, 1998Date of Patent: January 16, 2001Assignee: EKA Chemicals ABInventors: Charlotte Angel, Troy Berglind, Arne Frestad, Sven-Eric Lunner, Anders Waleij
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Patent number: 6113741Abstract: The invention relates to a process for the production of paper on a paper machine containing a dilution headbox in which a main aqueous flow containing cellulosic fibres and filler is mixed in said headbox with a diluting aqueous flow to form a resulting aqueous flow which is ejected onto a wire and dewatered to form a web of paper, wherein one or more components providing improved retention are introduced into the main aqueous flow and an additive resulting in slower dewatering and/or being selected from non-ionic and anionic organic polymers is introduced into the diluting aqueous flow.Type: GrantFiled: December 4, 1997Date of Patent: September 5, 2000Assignee: Eka Chemicals ABInventors: Kalle Kettunen, .ANG.ke Kjellander, Maria Norell
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Patent number: 6103064Abstract: The invention relates to a process for the production of paper from a suspension of cellulose containing fibres, and optional fillers, which comprises adding a water-soluble cationic or amphoteric branched acrylamide-based polymer and an anionic aluminium-containing silica sol to the suspension and forming and draining the suspension on a wire.Type: GrantFiled: May 13, 1998Date of Patent: August 15, 2000Assignee: Eka Chemicals ABInventors: Anna Asplund, Kjell Andersson, Erik Lindgren
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Patent number: 6100322Abstract: The invention relates to a process for the production of paper from a suspension of cellulose containing fibers, and optional fillers, comprising adding to the suspension a low molecular weight cationic organic polymer, a high molecular weight cationic or amphoteric polymer and anionic inorganic particles, forming and draining the suspension on a wire, wherein the low molecular weight polymer has a molecular weight below 700,000 and the high molecular weight polymer has a molecular weight above 1,000,000, said polymers being simultaneously added to the suspension.Type: GrantFiled: October 2, 1998Date of Patent: August 8, 2000Assignee: Eka Chemicals ABInventors: Michael Persson, Joakim Carlen, Hans Johansson, Carlos Cordoba
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Patent number: 6087457Abstract: The invention relates to a method of surface sizing cellulose based products such as paper, board and paper board. The method comprises applying to the surface of said products an aqueous dispersion of a copolymer obtainable by free-radical emulsion polymerization of a monomers mixture comprising at least one monomer selected from the group consisting of styrene and derivatives thereof; at least one monomer selected from the group consisting of esters of ethylenically unsaturated carboxylic acids and alkanols; and at least one monomer selected from the group consisting of ethylenically unsaturated carboxylic and sulfonic acids and salt thereof; optionally in combination with other ethylenically unsaturated copolymerizable monomers.Type: GrantFiled: March 29, 1996Date of Patent: July 11, 2000Assignee: Eka Chemicals ABInventor: Yi-Guan Tsai
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Patent number: 6083347Abstract: The present method generally relates to a method for production of absorbent material having improved sorptive capacity, which material comprises cellulosic fibres, wherein said method comprises treating said fibres, in the presence of water, with a hydrophobic substance having a specific surface area of at least 50 m.sup.2 /g, wherein the treatment comprises contacting said substance and said fibres together when the fibres have a dry content of at least 20%.Type: GrantFiled: March 24, 1997Date of Patent: July 4, 2000Assignee: Eka Chemicals ABInventors: Ingemar Thebrin, Svante W.ang.hlen, Erik Lindgren, Kerstin Malmborg
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Patent number: 6071431Abstract: The invention relates to particles comprising a peroxy compound with capability of releasing hydrogen peroxide or peroxy acids in aqueous solutions and an amino acid of the formula (HOOC) .sub.2 N--C.sub.n H.sub.m COO--R in which R is H,CH.sub.2 OH, or CH.sub.3, n is 1, 2 or 3 and m is 0-2n; or a salt thereof. The invention also relates to use of the particles and a composition comprising such particles.Type: GrantFiled: March 18, 1997Date of Patent: June 6, 2000Assignee: EKA Chemicals ABInventors: Hans Lagnemo, Monica Jigstam
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Patent number: 5985235Abstract: The invention relates to a method of activating a catalyst for hydrogenation of anthraquinones or derivatives thereof used in production of hydrogen peroxide comprising the step of treating the catalyst with an acid. The invention also relates to a method of producing hydrogen peroxide.Type: GrantFiled: December 3, 1996Date of Patent: November 16, 1999Assignee: EKA Chemicals ABInventors: Mats Nystrom, Mikael Siverstrom
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Patent number: 5980717Abstract: A substantial and increasing problem with the pulping chemical recovery system, is the presence of chloride and potassium in the spent liquor entering the recovery boiler. Chloride and potassium increase the stickiness of carryover deposits and dust particles to the recovery boiler tubes, which accelerate fouling and plugging in the upper part of the recovery boiler. The present invention relates to a process by which the content of potassium ions in a recovery system for pulping chemicals can be reduced. The process comprises bringing spent liquor to a recovery boiler, burning said spent liquor, collecting precipitator dust formed, forming a solution by dissolving the precipitator dust in a liquid, where the solution of precipitator dust is subjected to a treatment with an inorganic ion exchange material in order to remove at least a part of the potassium therein.Type: GrantFiled: December 29, 1997Date of Patent: November 9, 1999Assignee: Eka Chemical ABInventors: Roland Pudas, Magnus Linsten, Roy Hammer-Olsen, Bjorn Svedin, Ingrid Velander
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Patent number: 5961803Abstract: An increasing problem with the pulping chemical recovery system, is the presence of chloride and potassium in the recovery boiler. Chloride and potassium increase inter alia the stickiness of carryover deposits and dust particles to the recovery boiler tubes, which accelerate fouling, corrosion and plugging of the recovery boiler. As the environmental legislation becomes more stringent, the degree of system closure increases. The present invention relates to a process by which the collected precipitator dust is leached, at a temperature exceeding 50.degree. C., for a residence time sufficient to get a chloride and potassium enriched leach solution and to remove at least a part of the content of metal ions in a solid phase. Said leach solution is electrochemically treated, preferably in an electrodialysis cell, in order to remove at least a part of the chloride and potassium therein. By the present process, the problem of sticky deposits in the recovery boiler can be substantially reduced.Type: GrantFiled: July 9, 1996Date of Patent: October 5, 1999Assignee: Eka Chemicals ABInventors: Johan Landfors, Roy Hammer-Olsen, Kimona Haggstrom
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Patent number: 5961948Abstract: The invention relates to a method of producing hydrogen peroxide by direct reaction between hydrogen and oxygen in an aqueous reaction medium, in which method hydrogen and oxygen are contacted with a catalyst suspended into the reaction medium, and the catalyst is a catalytically active surface material deposited on a support of porous silica, alumina or non-fluorinated carbon having a BET surface less than about 150 m.sup.2 /g, wherein pores with a diameter exceeding about 10 nm constitute more than about 50% of the total pore volume. The invention also relates to a catalyst useful in the claimed method.Type: GrantFiled: June 24, 1997Date of Patent: October 5, 1999Assignee: EKA Chemicals ABInventor: Johan Wanng.ang.rd
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Patent number: 5938894Abstract: A method in which a sheet of cellulosic fibres is shredded into fluff wherein, prior to shredding, the fibres are treated in the presence of water with a hydrophobic substance having a specific surface area of at least about 50 m.sup.2 /g, to yield improved sorptive capacity; fluff obtainable by the method; absorbent articles comprising such fluff; use of a substance of said kind for improving the sorptive capacity of absorbent material comprising the fibers; a process for production of absorbent material obtained by shredding a sheet of such fibers in which the fibers, prior to shredding, have been treated in the presence of water with a substance of said kind to yield improved sorptive capacity; and absorbent material obtainable from the process.Type: GrantFiled: March 24, 1997Date of Patent: August 17, 1999Assignee: Eka Chemicals ABInventors: Ingemar Thebrin, Svante W.ang.hlen, Erik Lindgren, Kerstin Malmborg
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Patent number: 5932000Abstract: A method for preparing concrete or mortar in which a mixture of a hydraulic binder, aggregates, water, and colloidal silica is prepared. The relative standard deviation of the particle size distribution by numbers of the colloidal silica is at least about 30%. The invention also relates to concrete or mortar obtainable by the method.Type: GrantFiled: September 12, 1997Date of Patent: August 3, 1999Assignee: EKA Chemicals ABInventors: Hans Bergqvist, Satish Chandra
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Patent number: 5929015Abstract: The invention relates to particles having a core comprising a peroxy compound with capability of releasing hydrogen peroxide or peroxy acids in aqueous solutions. The particles have a coating containing a silicate, and a water soluble magnesium salt, and the core and/or the coating contains an aliphatic organic compound or a salt thereof as a chelating agent. The invention also relates to preparation and use of the particles as well as a composition containing such particles.Type: GrantFiled: March 18, 1997Date of Patent: July 27, 1999Assignee: EKA Chemicals ABInventors: Hans Lagnemo, Monica Jigstam
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Patent number: 5916447Abstract: A method for treatment of water in which an aqueous solution containing a freshly made polymerised iron substance is produced, the produced polymerised iron substance is aged sufficiently long to provide for efficient treatment of water, and the aqueous solution containing aged polymerised iron substance is added to the water to be treated.Type: GrantFiled: October 15, 1997Date of Patent: June 29, 1999Assignee: Eka Chemicals ABInventors: Felix Hulten, Goran Sivertsson