Calcium Sulfate Specified (e.g., Gypsum, Anhydrite, Plaster Of Paris, Etc.) Patents (Class 106/732)
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Publication number: 20150101510Abstract: The invention provides methods and compositions for producing and grinding cement. The method makes use of combining an additive with one or more components selected from a list of gypsum, hemihydrate, anhydrite, calcium sulfate to form a mixture then blending the mixture with clinker, and finally grinding the mixture and clinker to form cement. By adding the additives before grinding the amount of water and energy needed for mixing is reduced.Type: ApplicationFiled: October 14, 2014Publication date: April 16, 2015Applicant: ECOLAB USA INC.Inventor: Bo L. Tran
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Patent number: 8845801Abstract: Bone cements and methods provided include a bone cement composition having collective attributes and properties desirable for initial fixation as well as interventional applications. Compositions include an amount of Portland cement and an amount of calcium sulfate.Type: GrantFiled: December 29, 2010Date of Patent: September 30, 2014Assignee: Regents of the University of MinnesotaInventors: Wook-Jin Seong, Young Cheul Heo, Hyeon Cheol Kim, Iel Yong Sung, Soo Cheol Jeong
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Publication number: 20140205751Abstract: A mortar composition in the form of a dry powder, ready for use, comprising at least one powdery binder and at least one aggregate, as well as possibly at least one standard additive and/or adjuvant, and formed from particles, at least some of which, referred to as fine particles, are liable to produce an emission of dust, characterised in that it also comprises a fluid additive that consists of least one non-polar hydrocarbon organic substance and that has a capacity for agglomeration of the said fine particles, and in that the dry mortar composition comprises agglomerates of line particles formed by the fluid additive.Type: ApplicationFiled: March 7, 2014Publication date: July 24, 2014Applicant: PAREXGROUP SAInventors: Alain Laudet, Daniel Daviller
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Patent number: 8648120Abstract: The present invention provides a liquid rheology modifier containing compounds (A) and (B) selected from combination (1) of compound (A) selected from cationic surfactants and compound (B) selected from anionic aromatic compounds and combination (2) of compound (A) from cationic surfactants and compound (B) selected from brominated compounds; and dicarboxylic acid (C).Type: GrantFiled: September 5, 2007Date of Patent: February 11, 2014Assignee: Kao CorporationInventors: Koji Koyanagi, Hotaka Yamamuro, Toshiharu Kojima
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Publication number: 20130036948Abstract: Provided herein are compositions, methods, and systems for a material containing metastable carbonate and stabilizer. Methods for making the compositions and using the compositions are also provided.Type: ApplicationFiled: April 26, 2012Publication date: February 14, 2013Inventors: MIGUEL FERNANDEZ, Irvin Chen, Patricia Tung Lee, Matthew Ginder-Vogel
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Patent number: 8105500Abstract: A slurry rheology modifier comprises a first water-soluble low-molecular compound [referred to hereinafter as compound (A)] and a second water-soluble low-molecular compound [referred to hereinafter as compound (B)] being different from the compound (A), wherein the viscosity of an aqueous solution at 20° C. prepared by mixing an aqueous solution SA (with a viscosity at 20° C. of 100 mPa·s or less) of compound (A) with an aqueous solution SB (with a viscosity at 20° C. of 100 mPa·s or less) of compound (B) in the ratio of 50/50 by weight can be at least twice as high as the viscosity of either aqueous solution before mixed.Type: GrantFiled: April 30, 2008Date of Patent: January 31, 2012Assignee: Kao CorporationInventors: Hotaka Yamamuro, Koji Koyanagi, Daisuke Shiba
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Patent number: 8021476Abstract: The invention relates to gypsum mortar with expanded vermiculite added with citric acid and tartaric acid and to the method for obtaining same, containing the following elements in the following proportions: between 40% and 70% calcium sulphate; between 40% and 70% laminated expanded vermiculite; between 0.05% and 0.3% citric acid; between 0.05% and 1% tartaric acid; between 0.01% and 0.5% sodium or potassium citrate; and water q.s.p. 1000 ml, in which, for surface coating, the added vermiculite is obtained following treatment in a vertical furnace, which provides improved grain size and sheets of exfoliated vermiculite without water or air, and the mortar is provided with citric acid and tartaric acid, copper sulphate and sodium or potassium scitrate, with the water being added before the mixture is produced.Type: GrantFiled: March 13, 2009Date of Patent: September 20, 2011Assignee: Fire Test, S.L.Inventors: Barbara Roman Aleman, Pilar Torres Zacarias
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Patent number: 7910230Abstract: The preparation of gypsum parts (dihydrate calcium sulfate) with high mechanical strength is obtained with the aid of water layers with nanometric thickness. Calcium sulfate is used, dihydrate as well as hemihydrate, to obtain parts from these two materials, pure or mixed, especially to use in construction work, where the parts are prepared by compressing their slightly humidified powders.Type: GrantFiled: September 21, 2006Date of Patent: March 22, 2011Assignee: Inovamat, Inovacao Em Materiais Ltda.Inventors: Milton Ferreira de Souza, Hebert Luis Rossetto, Wellington Massayuki Kanno
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Patent number: 7901506Abstract: In this invention a cementitious capillary crystalline waterproof material with an eka-molecular sieve structure and its manufacturing method is disclosed. The major ingredient of this material is Portland cement; the accessories include silicon dioxide, alumina, magnesia, calcium sulphonate, methlycellulose, quick-setting agent and sodium aluminate, etc. Put separately major ingredient and accessories premixed in given proportion separately into the major ingredient bin and the accessory bins. The major ingredient passing through an impulse flowmeter is carried to the dosing machine; and in the same time, the premixed accessories are automatically weighed by the weighing device using gewichtsabnahme method when they are carried to the above dosing machine; they are mixed in the premixing machine and the refine-mixing machine and prepared to the product. The product is mixed with water and forms slurry.Type: GrantFiled: June 2, 2008Date of Patent: March 8, 2011Inventor: Huidong Zhang
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Patent number: 7337587Abstract: A construction assembly includes a plurality of plaster boards, each of the plaster boards having a plaster body and at least one sheet of liner, the liner including an inner surface attached to the plaster body and an outer surface having an outer face; wherein said plaster boards are assembled creating at least one joint; and a joint-pointing coat jointing said plaster boards to form a substantially plane outer surface including the outer surface of said at least one joint and said outer surface of said liner, wherein the composition of the joint-pointing coat is adapted for the finishing of said at least one joint; wherein both the joint-pointing coat in the dry state and the outer face of the sheet of liner are adapted to form an overall surface having a substantially homogeneous coloration.Type: GrantFiled: June 1, 2004Date of Patent: March 4, 2008Assignee: Lafarge PlatresInventors: Francois Zuber, Claude Leclercq, Pascal Bourne-Chastel
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Publication number: 20070289744Abstract: Cementitious compositions are provided that can be use in drilling oil and gas well applications. The compositions include a source of hydraulically settable cement, calcium carbonate, free lime and alkali ions, calcium sulfate and an organic component. Methods for cementing a casing and liners and for remedial operations such as plugging back and squeeze cementing are also provided.Type: ApplicationFiled: June 20, 2006Publication date: December 20, 2007Applicant: Holcim (US) Inc.Inventors: Arlen Earl Bingamon, Stephen C. Morrical, Francis Allison Innis, Anthony Martin Sorcic
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Patent number: 7052543Abstract: The current invention provides an improved permeable cement composition for formation of downhole sand screens. The improved composition includes an effective amount of a surfactant. Addition of the surfactant to the permeable cement composition yields at least a pumpable slurry with a minimal amount of water or brine solution.Type: GrantFiled: March 1, 2005Date of Patent: May 30, 2006Assignee: Halliburton Energy Services, Inc.Inventors: Philip D. Nguyen, Johnny A. Barton
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Patent number: 6626991Abstract: The invention relates to a cement slurry for cementing an oil well or the like, the slurry having a density lying in the range 0.9 g/cm3 to 1.3 g/cm3, and being constituted by a solid fraction and a liquid fraction, having porosity (volume ratio of liquid fraction over solid fraction) lying in the range 38% to 50%. The solid fraction is constitued by a mixture of lightweight particles, microcement and optionally portland cement and gypsum. Such cements have remarkable mechanical properties due to their very low porosity in spite of having very low density.Type: GrantFiled: July 2, 2002Date of Patent: September 30, 2003Inventors: Bruno Drochon, Andre Garnier
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Patent number: 6607592Abstract: The invention concerns a composition in dry state for mortar or concrete, comprising a cement and an antishrinkage agent. The invention is characterized in that the antishrinkage agent consist of a calcium sulphate, particularly an anhydrous calcium sulphate, associated with at least a glycol ether.Type: GrantFiled: October 31, 2000Date of Patent: August 19, 2003Assignee: VicatInventor: Jean-Dominique Ceccaldi
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Publication number: 20030110983Abstract: The present invention uses a three-dimensional metal reinforcing aggregate as an aggregate in producing a common ready-mixed concrete according to its object of use in producing the ready-mixed concrete and a mortar. Since it is the three-dimensional metal reinforcing aggregate, it is a technique to enhance the external pressure, internal pressure and tensile strength when the ready-mixed concrete is hardened and solidified. Since the three-dimensional metal reinforcing aggregate is forced into between an aggregate and an aggregate in the ready-mixed concrete, the aggregate and the aggregate are further bound, thereby enhancing the internal pressure, the external pressure and the tensile strength. For example, if split, crack and the like is generated on the concrete body near the cold joint of the placed concrete, the conventional concrete body leads to drop thereof and causes an accident.Type: ApplicationFiled: December 12, 2001Publication date: June 19, 2003Inventor: Yukinori Hayashi
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Patent number: 6478868Abstract: The present invention provides improved early-enhanced strength cement compositions and methods. The cement compositions can be utilized in surface construction projects as well as in the construction of oil, gas and water wells. The improved cement compositions of this invention are basically comprised of a hydraulic cement, water present in an amount sufficient to form a slurry and hydrophobic silica powder.Type: GrantFiled: August 26, 1999Date of Patent: November 12, 2002Assignee: Halliburton Energy Services, Inc.Inventors: Baireddy R. Reddy, Ronald J. Crook, Bryan K. Waugh, Russell M. Fitzgerald, Dennis W. Gray, Brent E. Traxel
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Patent number: 6447597Abstract: An additive, a mixture incorporating the additive and a method of formulating a mortar incorporating the additive. The additive is based on calcium sulfoaluminate composed of C3AH6 and CAH10 where C=calcium oxide, A=aluminum oxide and H=water. The admixture includes gypsum and calcium hydroxide. The calcium aluminum hydrates are obtained by hydration of high alumina cement particles to eliminate any lack of hydration in the core of the particle. The method involves the preparation of such particles and the mix incorporates the particles to produce a homogeneously hydrated cement additive.Type: GrantFiled: February 4, 2000Date of Patent: September 10, 2002Assignee: National Research CouncilInventors: Wellington L. Repette, Noel P. Mailvaganam
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Patent number: 6436184Abstract: The invention concerns a hydration modifying agent for mortar and concrete comprising a combination of 30 to 80% of calcium sulphate, 3 to 60% of ethylene/propylene oxide copolymer and 0.5 to 6% of an activator for the copolymer. The invention also concerns a Portland dry cement comprising 2 to 10 wt. % of said hydration modifying agent and a method for preparing such a mortar or concrete composition, and a self-spreading concrete topping made from said mortar or concrete composition.Type: GrantFiled: June 26, 2000Date of Patent: August 20, 2002Assignee: VicatInventors: Jean-Dominique Ceccaldi, Laurent Izoret
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Patent number: 6350304Abstract: The construction material comprises a construction base material and microcapsules inside of which liquid containing hinokitiol is incorporated and a plurality of which are to be mixed into the construction base material and the liquid in the microcapsules transudes into the construction base material because the microcapsules collapse due to at least change with time.Type: GrantFiled: October 30, 2000Date of Patent: February 26, 2002Assignee: Topics Co., Ltd.Inventor: Eisaku Tozaka
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Patent number: 6290772Abstract: This invention relates to enhancing the compressive strength of cements after 1, 3, 7 and 28 days following hydration and to improving porosity and finished surfaces of the hardened cements and concretes made therefrom. The improved cements are prepared using certain hydroxylamine additives in amounts of up to 0.1% which preferably are added during grinding of the cement in which case the amines further act as grinding aids.Type: GrantFiled: September 30, 1999Date of Patent: September 18, 2001Assignee: W.R. Grace & Co.-Conn.Inventors: Josephine Ho-wah Cheung, David Francis Myers
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Patent number: 6241815Abstract: A composition for use in construction materials, which may be substituted for high performance concrete, patching materials, joint compounds, and the like, such as backer boards or panels, which includes a settable calcium sulfate, preferably a hemihydrate, Portland cement, a finely divided pozzolanic material, lime, and an aggregate, optionally including other additives. The volume ratio of the aggregate to the combined calcium sulfate, Portland cement, pozzolanic material, and lime (a cementitious binder) is equal to or greater than 2/1. Panels made from this composition are useful, particularly when exposed to water since they have good dimensional stability.Type: GrantFiled: August 10, 1999Date of Patent: June 5, 2001Assignee: United States Gypsum CompanyInventor: David Bonen
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Patent number: 6048393Abstract: This invention relates to enhancing the compressive strength of cements after 1, 3, 7 and 28 days following hydration and to improving porosity and finished surfaces of the hardened cements and concretes made therefrom. The improved cements are prepared using certain hydroxylamine additives in amounts of up to 0.1% which preferably are added during grinding of the cement in which case the amines further act as grinding aids.Type: GrantFiled: May 26, 1998Date of Patent: April 11, 2000Assignee: W.R. Grace & Co. -Conn.Inventors: Josephine Ho-wah Cheung, David Francis Myers
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Patent number: 5958131Abstract: A composition suitable for adding to water to produce a water-resistant hydraulic solid which composition comprises components (a), (b) and (c) as follows:(a) calcium sulphate hemihydrate;(b) portland cement;(c) calcined clay having a pozzolanic activity;wherein the percentages by weight of components (a), (b) and (c) in the said composition are in the respective ranges:(a) from 20% to 98%;(b) from 1% to 50%;(c) from 1% to 30%;the percentages of components (a), (b) and (c) adding to 100% in the three component composition.Type: GrantFiled: December 18, 1997Date of Patent: September 28, 1999Assignee: ECC International Ltd.Inventors: Anthony Hales Asbridge, Thomas Richard Jones
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Patent number: 5858083Abstract: Cementitious binders include calcium sulfate beta-hemihydrate, a cement component comprising Portland cement, and either silica fume or rice-husk ash. The silica fume or rice-husk ash component is at least about 92 wt % amorphous silica and has an alumina content of about 0.6 wt % or less.Type: GrantFiled: May 19, 1997Date of Patent: January 12, 1999Assignee: National Gypsum CompanyInventors: Elisha Stav, Edward A. Burkard, Ronald S. Finkelstein, Daniel A. Winkowski, Lambert J. Metz, Patrick J. Mudd
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Patent number: 5806594Abstract: Foamed cement slurry compositions and a process or method for cementing well casings or pipes utilizing such compositions are described, the compositions being characterized by critical ratios of particular solid and liquid components. The slurry compositions formed provide unique properties such as rapid set or hydration, and are designed particularly for use with weakly consolidated formations.Type: GrantFiled: March 31, 1997Date of Patent: September 15, 1998Assignee: Schlumberger Technology CorporationInventors: David A. Stiles, Jean Mari Guy de Rozieres, deceased
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Patent number: 5788762Abstract: Novel cementitious systems comprised of gypsum, calcined clay, and clinker consisting essentially of hydraulic calcium silicates are disclosed which have the following properties: (1) a water demand of less than about 33% nc; (2) one-day strengths of at least about 1000 psi; and (3) low alkali functionality. By increasing the amount of calcined clay, the resulting cementitious system will sequentially gain the following properties: (1) alkali non-reactiveness; (2) alkali resistance; and (3) low chloride permeability. Novel methods of preparing the novel cementitious systems of this invention are also disclosed. The novel methods not only reduce production costs by decreasing fuel and raw material consumption, but they also allow the cement producer to proactively address significant environmental concerns related to the manufacturing process.Type: GrantFiled: January 27, 1997Date of Patent: August 4, 1998Assignee: Ash Grove Cement CompanyInventors: Gregory S. Barger, Eric R. Hansen
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Patent number: 5785751Abstract: A composition of hydraulic cement is disclosed, having low water demand, high strength and low fragility. The cement comprises finely ground Portland cement clinker, calcium sulfate and a dry modifier containing an organic water reducing component in a weight percent ratio of 91 to 97:2 to 7:0.085 to 4, respectively. The clinker particles comprise three fractions, I, II and III chemically bonded with the organic water reducing component and having respective particle sizes: I--0.05 to 10 mkm in a weight percent of 15.3 to 34.3; II--10.1 to 30 mkm in a weight percent of 37.2 to 77.5; III--30.1 to 80 mkm in a weight percent of 4.2 to 19.6; plus a fraction IV--having a particle size more than 80 mkm in a weight percent less than 4.9 and free of the modifier. The calcium sulfate comprises a fraction of particles of a size 0.5 to 15 mkm, free of the modifier. The dry modifier is chemically bonded with the three clinker fractions in the following weight percent quantities: I--0.045 to 1.7; II--0.02 to 2.Type: GrantFiled: April 16, 1996Date of Patent: July 28, 1998Assignee: Cement Technology CorporationInventors: Nikolay Fedorovich Bashlykov, Sergey Alekseevich Zubehin, Valery Nicolaevich Serduk, Vicheslav Rovimovitch Falikman, Boris Emmanuilovich Yudovetch, Jaime Moreno, Claudio Augusto Eberhardt, Alfonso Cadaval, Nagmet Suleimanov-Gonzalez, Shahviran Teimurogly Babaev
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Patent number: 5749963Abstract: The hardenable mortar composition consists of a bonding agent component including a hydraulic bonding agent, such as cement, gypsum or mortar, and a paste-forming agent consisting of a liquid solvent inert with respect to the hydraulic bonding agent, and an aqueous component kept separate from the bonding agent component until the two components are mixed to form a hardened mortar composition. The aqueous component includes water and a hydrophobic adsorbent or absorbent. The hydrophobic adsorbent or absorbent is included in the aqueous component to avoid the emergence of the paste-forming agent, which is at the very least unsightly, when the aqueous component is mixed with the bonding agent component. The hydrophobic adsorbent or absorbent binds the paste-forming agent which would otherwise escape during mixing and remains as an inert additive in the setting mortar composition, without reducing the hardness thereof.Type: GrantFiled: February 13, 1997Date of Patent: May 12, 1998Assignee: fischerwerke, Artur Fischer GmbH & Co. KGInventors: Norbert Arnold, Willi Haug, Stefan Lind
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Patent number: 5741357Abstract: A hydraulic cement composition is disclosed which utilizes as part of an expansive component novel coated particles of high alumina cement. The particles have a core of substantially unhydrated high alumina cement and an outer layer of hydration products of the core, which outer layer delays the reaction of the particles with other materials in the composition. By varying the nature and relative amounts of the coated particles the amount the cement composition may expand and the setting time of the cement may be varied. The coated particles may be formed by partial hydration, drying and grinding of a mixture of high alumina cement powder alone with water.Type: GrantFiled: August 21, 1995Date of Patent: April 21, 1998Inventor: Shamim A. Sheikh
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Patent number: 5723226Abstract: A fire resistant article comprising at least about 65 wt. % gypsum dihydrate, reinforcing fibers disposed substantially homogeneously throughout said set gypsum dihydrate, inorganic binder, and optionally refractive filler. This composition provides superior resistance to damage when subjected to a stream of pressurized water as from a fire hose.Type: GrantFiled: June 7, 1995Date of Patent: March 3, 1998Assignee: G-P Gypsum CorporationInventors: Hubert C. Francis, Anne H. Ksionzyk
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Patent number: 5718759Abstract: A cementitious composition useful for water-resistant construction materials, including floor underlayments, backing boards, self-leveling floor materials, road patching materials, fiberboard, fire-proofing sprays, and fire-stopping materials includes about 20 wt. % to about 75 wt. % calcium sulfate beta-hemihydrate, about 10 wt. % to about 50 wt. % Portland cement, about 4 wt. % to about 20 wt. % silica fume and about 1 wt. % to about 50 wt. % pozzolanic aggregate. The Portland cement component may also be a blend of Portland cement with fly ash and/or ground blast slag.Type: GrantFiled: October 18, 1996Date of Patent: February 17, 1998Assignee: National Gypsum CompanyInventors: Elisha Stav, Edward A. Burkard, Ronald S. Finkelstein
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Patent number: 5685903Abstract: A cementitious composition useful for water-resistant construction materials, including floor underlayments, backing boards, self-leveling floor materials, road patching materials, fiberboard, fire-proofing sprays, and fire-stopping materials includes about 20 wt. % to about 75 wt. % calcium sulfate beta-hemihydrate, about 10 wt. % to about 50 wt. % Portland cement, about 4 wt. % to about 20 wt. % silica fume and about 1 wt. % to about 50 wt. % pozzolanic aggregate. The Portland cement component may also be a blend of Portland cement with fly ash and/or ground blast slag.Type: GrantFiled: September 13, 1996Date of Patent: November 11, 1997Assignee: National Gypsum CompanyInventors: Elisha Stav, Edward A. Burkard, Ronald S. Finkelstein
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Patent number: 5639298Abstract: A set control composition and/or interground blend of materials including a calcium sulfate material and magnesium sulfate.Type: GrantFiled: November 27, 1995Date of Patent: June 17, 1997Assignee: Air Products and Chemicals, Inc.Inventors: F. MacGregor Miller, Timothy Jay Roth, William Russell Welliver, John Robert Brown
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Patent number: 5626665Abstract: Novel cementitious systems comprised of gypsum, calcined clay, and clinker consisting essentially of hydraulic calcium silicates are disclosed which have the following properties: (1) a water demand of less than about 33% nc; (2) one-day strengths of at least about 1000 psi; and (3) low alkali functionality. By increasing the amount of calcined clay, the resulting cementitious system will sequentially gain the following properties: (1) alkali non-reactiveness; (2) alkali resistance; and (3) low chloride permeability. Novel methods of preparing the novel cementitious systems of this invention are also disclosed. The novel methods not only reduce production costs by decreasing fuel and raw material consumption, but they also allow the cement producer to proactively address significant environmental concerns related to the manufacturing process.Type: GrantFiled: November 4, 1994Date of Patent: May 6, 1997Assignee: Ash Grove Cement CompanyInventors: Gregory S. Barger, Eric R. Hansen
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Patent number: 5273579Abstract: The present invention concerns a quick setting composition capable of obtaining satisfactory strength developability irrespective of the fluctuation of the ingredients in a metallurgical slag, excellent in the strength developability at cold temperature, easy for coagulation control and inexpensive as well, which contains a cement ingredient comprising portland cement and/or mixed cement, 2 to 50% by weight at the integral ratio of a quick setting agent prepared by adding 3 to 20% by weight of an alkali carbonate at an internal ratio to a mixture comprising 40 to 95% by weight of a finely powdery metallurgical slag and 5 to 60% by weight of II-type anhydrous gypsum, based on the cement ingredient, and 0.1 to 5% by weight of a coagulation controlling agent comprising an organic acid type coagulation retarder and an alkali sulfate and/or calcium salt based on the total weight of the cement ingredient and the quick setting ingredient.Type: GrantFiled: April 28, 1993Date of Patent: December 28, 1993Assignee: Mitsubishi Mining and Cement Co., Ltd.Inventors: Yoshio Tanaka, Tetsuro Tsutsumi, Keiji Saito, Hisanobu Tanaka
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Patent number: 5155959Abstract: Firedoor constructions manufactured from board compositions containing calcium sulfate in hemi-hydrate or anhydrous form and fibrous additives, including pulped paper fibers preferably derived from waste newspaper, capable of being formed into firedoor members having superior mechanical properties and/or fire resistance.Type: GrantFiled: May 14, 1991Date of Patent: October 20, 1992Assignee: Georgia-Pacific CorporationInventors: Turner W. Richards, Hubert C. Francis, George F. Fowler
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Patent number: 5133806Abstract: There is disclosed a softy mud solidifying agent which comprises cement, and at least two members selected from the group consisting of pozzolanic substances, inorganic compounds and organic compounds. The solidifying agent is capable of solidifying dredged earth, sand, softy mud, etc. in such a manner that their mixture can be re-cast into water to form submerged banks, artificial fish-gathering places, etc., without causing water pollution.Type: GrantFiled: January 6, 1992Date of Patent: July 28, 1992Assignees: Fujita Corporation, Onoda Chemico Co., Ltd.Inventors: Hiroyuki Sakamoto, Masao Sagara, Masao Shimoda, Kitsugi Kyoichi
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Patent number: 4347167Abstract: A semiconducting internal boundary layer ceramic composition having a fine grain structure suitable for use in thin-layer multilayer capacitors is made in one step by firing a mixture comprising a major amount of finely divided strontium titanate, a minor amount of a compound containing either strontium or titanium, or an element functionally equivalent thereto, a minor amount of a semiconductor forming ingredient (dopant), the identity of which depends on whether the mixture is rich in strontium or in titanium, and a minor amount of a counterdopant selected from cuprous oxide or silver oxide. When the mixture is rich in titanium, the chemical doping agent used to produce semiconductivity is an oxide of a trivalent metal selected from bismuth, boron, iron, antimony, lanthanum and the rare earth and transition metals. When the mixture is rich in strontium, the dopant is an oxide of a pentavalent or hexavalent metal selected from tungsten (+6), niobium (+5), tantalum (+5), and molybdenum (+6).Type: GrantFiled: October 1, 1980Date of Patent: August 31, 1982Assignee: University of Illinois FoundationInventors: David A. Payne, Sang M. Park
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Patent number: 4310402Abstract: In a high temperature gas measuring device consisting of a zirconia oxide solid electrolyte cell bonded to a support member, a sealant exhibiting a thermal coefficient of expansion comparable to zirconia and a melting point in excess of 1000.degree. C. is used to seal the cell to the support member. The preferred sealants which meet these requirements include:(1) 3 MgO.sup.. Al.sub.2 O.sub.3.sup.. 6 SiO.sub.2(2) 52% Nd.sub.4 (SiO.sub.4).sub.3, 48% Ca.sub.2 SiO.sub.4(3) 57% La.sub.4 (SiO.sub.4).sub.3, 43% Ca.sub.2 SiO.sub.4(4) 50% Y.sub.4 (SiO.sub.4).sub.3, 50% Ca.sub.2 SiO.sub.4(5) (a) La.sub.2 O.sub.3.sup.. Al.sub.2 O.sub.3 : 50 mol % of each (b) 40% La.sub.2 O.sub.3.sup.. 60% Al.sub.2 O.sub.3.Type: GrantFiled: November 5, 1980Date of Patent: January 12, 1982Assignee: Westinghouse Electric Corp.Inventors: Arnold O. Isenberg, David F. Bradley
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Patent number: 4286905Abstract: A method is disclosed for removing stock from a metal part comprised of steel, malleable cast iron or nodular cast iron. A moving relationship is established between the part and a cutting tool formed of a substantially full dense hot pressed ceramic material consisting essentially of a generally uniform mixture of 50-70% by weight Al.sub.2 O.sub.3 and the remainder substantially Si.sub.3 N.sub.4. The tool is advanced into the surface of the part at a predetermined depth of cut and feed rate which results in the removal of stock from the part during periods of relative movement. A portion of the Al.sub.2 O.sub.3 may be replaced by up to 15% stabilized ZrO.sub.2 or HfO.sub.2 to further improve strength at higher temperatures.Type: GrantFiled: April 30, 1980Date of Patent: September 1, 1981Assignee: Ford Motor CompanyInventor: Shyam K. Samanta
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Patent number: 4284432Abstract: Ceramic powder material mainly consists of silicon nitride wherein the content of oxygen combined with generally unavoidable impurities as measured by activation analysis accounts for less than 2% by weight. The above-mentioned ceramic powder material can also be prepared preferably by the method which comprises the step of heating raw ceramic powder material mainly consisting of silicon nitride to 1,400.degree. C. to 1,900.degree. C. in the presence of a separately prepared nonsintered molding of ceramic material or sintered molding of ceramic material having a porosity of at least 10%.Type: GrantFiled: September 21, 1979Date of Patent: August 18, 1981Assignee: Tokyo Shibaura Electric Co. Ltd.Inventors: Katsutoshi Nishida, Michiyasu Komatsu, Tadashi Miyano
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Patent number: 4283752Abstract: A dielectric material which meets the temperature requirements for X7R grade capacitors consists of a fired ternary niobate composition. A dielectric constant of at least 2000 and a limited change in dielectric constant with temperature is present in compositions having the approximate formula:Pb.sub.x .multidot.Ba.sub.y .multidot.Sr.sub.z (Nb.sub.2 O.sub.6)where x, y and z represent the mole fractions of each of Pb, Ba and Sr which are in the ranges of X=0.1 to 0.4, y=0.1 to 0.4, z=0.4 to 0.5, the sum of x, y and z being 1. Modifications which increase these ranges include doping the ternary niobate composition with a rare earth and substitution of Ta.sub.2 O.sub.5 for Nb.sub.2 O.sub.5. During preparation, the composition is heated in a cycle which produces a mixture of phases, primarily rhombohedral and tetragonal structures similar to those of PbNb.sub.2 O.sub.6.Type: GrantFiled: May 1, 1978Date of Patent: August 11, 1981Assignee: Corning Glass WorksInventor: Margaret M. Layton
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Patent number: 4280846Abstract: A mixture of oxides or salts of barium, titanium and tin (principal materials) are initially ground with two different classes of dopants. The first class consists of oxides or salts of rare earths or of elements such as antimony. The second class consists of oxides or salts of elements such as manganese or copper. After calcining and sintering, cooling of the ceramic body is obtained by adjusting to a very low rate (negative gradient of 10 to 30.degree. C. per hour) in a pure oxygen atmosphere.The material is primarily suited for use in capacitors having one or a number of layers which may be separated by electrodes inserted prior to sintering. The material has high apparent permittivity and can be employed at much higher voltages than in barrier-layer capacitors.Type: GrantFiled: July 27, 1979Date of Patent: July 28, 1981Assignee: Thomson-CSFInventors: Eliane Charles, Mieczyslaw Hildebrandt, Francois Buchy
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Patent number: 4280850Abstract: Polycrystalline ceramic bodies of Si.sub.3 N.sub.4 when prepared to obtain an intergranular phase which is substantially crystalline, exhibits significantly improved mechanical strength at elevated temperatures above 1,000.degree. C. up to 1600.degree. C. over bodies having glass-containing intergranular phases.Type: GrantFiled: June 15, 1978Date of Patent: July 28, 1981Assignee: GTE Laboratories, IncorporatedInventors: J. Thomas Smith, Carr L. W. Quackenbush, F. Joseph Reid
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Patent number: 4269641Abstract: A method for providing strong adhesion of two ceramic articles to each other or one ceramic article to an article of metallic copper, which method comprises applying, in the former adhesion, a powder mixture of CuS--LaCrO.sub.3 --SiO.sub.2 --Cu to the opposed surfaces of the two ceramic articles or, in the latter adhesion, a powder mixture of CuS--LaCrO.sub.3 --SiO.sub.2 to the opposed surfaces of the ceramic article and the article of metallic copper and, thereafter, heating the pair of articles in the air at a temperature of from 1000.degree. to 1200.degree. C.Type: GrantFiled: October 11, 1979Date of Patent: May 26, 1981Assignees: Agency of Industrial Science and Technology, Ministry of International Trade and IndustryInventors: Yoshihiro Ebata, Yasuo Toibana, Tsuneo Uetsuki, Saburo Kose, Makoto Kinoshita
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Patent number: 4266978Abstract: A non-aqueous gel of at least two metal oxides which is a precursor for glassy amorphous or crystalline mixed oxides is produced by reacting an alkoxide of one metal and a halide of another metal producing a low molecular weight polymeric reaction product, heating the reaction product to produce a polymeric product of substantially higher molecular weight, and heating the higher molecular weight polymeric product in air to remove its carbonaceous content.Type: GrantFiled: June 25, 1979Date of Patent: May 12, 1981Assignee: General Electric CompanyInventor: Svante Prochazka
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Patent number: 4265666Abstract: Ceramic material for a low temperature direct heating electron gun cathode, wherein it is constituted by a mixed ceramic material of a hexaboride of a refractory material consisting of at least one substance with a high emissive power from the group consisting of La, Sr, and Ba hexaborides and a conductive material, boron carbide, having a resistivity higher than that of an emissive substance, the structure of the ceramic material resulting from its production by cofritting of the said components.Type: GrantFiled: August 17, 1979Date of Patent: May 5, 1981Assignee: Commissariat a l'Energie AtomiqueInventors: Michel Contre, Philippe Martin, Monique Quetier
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Patent number: 4261753Abstract: The present invention relates to a structural composition useful in corrosive hydrogen-fluorine environments at temperatures in excess of 1400.degree. K. The composition is formed of a isostatically pressed and sintered or a hot-pressed mixture of lanthanum hexaboride particles and about 10-30 vol. % carbon. The lanthanum-hexaboride reacts with the high-temperature fluorine-containing bases to form an adherent layer of corrosion-inhibiting lanthanum trifluoride on exposed surfaces of the composition. The carbon in the composite significantly strengthens the composite, enhances thermal shock resistance, and significantly facilitates the machining of the composition.Type: GrantFiled: January 22, 1980Date of Patent: April 14, 1981Assignee: The United States of America as represented by the United States Department of EnergyInventors: Cressie E. Holcombe, Louis Kovach, Albert J. Taylor
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Patent number: 4248440Abstract: Disclosed is a coating for bearing faces of piston rings and a powder composition for plasma spray application of such coating. The plasma spray powder comprises 94%-98% by weight of aluminum oxide and titanium oxide and 2%-6% by weight of yttrium oxide. The inclusion of yttrium oxide in the aluminum oxide-titanium oxide coating composition reduces the tendency of the coating to blistering and spalling which resulting in coating loss during use of the ring. Intra-coating delamination is substantially reduced or eliminated.Type: GrantFiled: September 12, 1979Date of Patent: February 3, 1981Assignee: Ramsey CorporationInventor: Harold E. McCormick
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Patent number: 4247249Abstract: High temperature resistant turbine engine shrouds are formed of an amphoteric refractory oxide, a phosphate binding agent and optionally a stabilizer, reinforcement and/or porosity controller.Type: GrantFiled: September 22, 1978Date of Patent: January 27, 1981Assignee: General Electric CompanyInventor: Paul A. Siemers