Subsequent Treatment Process Patents (Class 536/76)
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Patent number: 5928613Abstract: In a production process of a cellulose acetate which comprises (a) a reduced pressure-acetylation step of acetylating a cellulose under a reduced pressure in the presence of sulfuric acid or other acidic catalyst, with distilling off a gaseous phase component of the reaction system out of the system, and (b) a post-acetylation step of allowing the acetylation to further proceed by increasing the pressure as compared with the pressure of the reduced pressure-acetylation step by means of release of the pressure reduction of the reaction system or the like, the shift operation from the reduced pressure-acetylation step to the post-acetylation step is conducted by taking a distilling rate of a distillate in the reduced pressure-acetylation step as an index to control the reaction temperature of the post-acetylation step.Type: GrantFiled: June 8, 1998Date of Patent: July 27, 1999Assignee: Daicel Chemical Industries, Ltd.Inventor: Mitsuru Yamashita
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Patent number: 5929229Abstract: The present invention relates to a process for preparing cellulose esters having a total DS/AGU of 0.1 to 3.0, said process consisting of contacting the following:(i) a cellulose material,(ii) a solubilizing amount of a solvent system comprising a carboxamide diluent or a urea-based diluent,(iii) an acylating reagent, and(iv) a titanium-containing compound.Type: GrantFiled: March 6, 1998Date of Patent: July 27, 1999Assignee: Eastman Chemical CompanyInventors: Kevin J. Edgar, Richard T. Bogan
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Patent number: 5919920Abstract: Cellulose acetate having a high moldability and low solution viscosity in spite of having a high average degree of polymerization is obtained. The low molecular weight components of cellulose acetate (e.g., CTA having average degree of acetylation of 59.0 to 62.5%) are eluted with a washing solvent to produce a cellulose acetate having a molecular weight distribution Mw/Mn of 1 to 1.7. As the washing solvent, those swell or partially dissolve the cellulose acetate, for example, those which dissolve 0.1 to 30% by weight of cellulose acetate can be used. This solvent includes, for example, a solvent having a solubility parameter .delta. of 7 to 12.5 (ketones, ethers, organic acid, esters, etc.).Type: GrantFiled: November 21, 1996Date of Patent: July 6, 1999Assignee: Daicel Chemical Industries, Ltd.Inventors: Ko Murakami, Toshinori Okano, Hiroki Taniguchi, Atsunobu Kiyose, Shu Shimamoto
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Patent number: 5914397Abstract: An object of the invention is to obtain cellulose acetate having improved physical properties, particularly film strength and improved flexibility of the molded product. Cellulose acetate having an average degree of acetylation of not less than 59%, viscosity average degree of polymerization (DP) of not less than 290. and concentrated solution viscosity (.eta.) according to falling ball viscosity method for viscosity average degree of polymerization (DP) expressed by the following formula (1):2.814.times.ln(DP)-11.753.ltoreq.ln(.eta.).ltoreq.7.28.times.ln(DP)-37.059( 1)and a process for the production thereof.Type: GrantFiled: November 21, 1996Date of Patent: June 22, 1999Assignee: Daicel Chemical Industries, Ltd.Inventors: Atsunobu Kiyose, Shu Shimamoto, Yuichiro Shuto, Hiroki Taniguchi
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Patent number: 5869646Abstract: In a production process of a cellulose acetate which comprises (a) a reduced pressure-acetylation step of acetylating a cellulose under a reduced pressure in the presence of sulfuric acid or other acidic catalyst, with distilling off a gaseous phase component of the reaction system out of the system, and (b) a post-acetylation step of allowing the acetylation to further proceed by increasing the pressure as compared with the pressure of the reduced pressure-acetylation step by means of release of the pressure reduction of the reaction system or the like, the shift operation from the reduced pressure-acetylation step to the post-acetylation step is conducted by taking a distilling rate of a distillate in the reduced pressure-acetylation step as an index to control the reaction temperature of the post-acetylation step.Type: GrantFiled: January 22, 1997Date of Patent: February 9, 1999Assignee: Daicel Chemical Industries, Ltd.Inventor: Mitsuru Yamashita
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Patent number: 5821359Abstract: The invention relates to a process for acetylation of lignocellulosic fibres (LF) using an acetylating agent comprising acetic anhydride at a temperature of above 140.degree. C. and a pressure of 100-150 kPa wherein raw or substantially raw LFs are treated with a superheated acetylating agent comprising at least 20 % w/w acetic anhydride for a duration of at least 1.5 minutes in an acetylation reactor (3), the treatment with superheated acetylating agent also ensuring that the acetylated LFs are substantially free from occluded, adsorbed or absorbed acetylating agent, the amounts of which are less than 5 % w/w of the acetylated LFs recovered from the base of a circulation cyclone (5), so as to substantially acetylate the LFs to achieve a weight gain of at least 2 %. The LFs may optionally be pre-treated, prior to being treated with the superheated acetylating agent, preferably by spraying, for a very short period of time.Type: GrantFiled: August 20, 1997Date of Patent: October 13, 1998Assignee: A-Cell Acetyl Cellulosics ABInventors: Helen Louise Nelson, David Ian Richards
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Patent number: 5821358Abstract: Methods and compositions are provided for the modification of polysaccharide structures using polysaccharidase binding or catalytic domains either alone or in tandem to modify the structure of polysaccharides. These methods and compositions are exemplified by the use of cellulase binding and catalytic domains to polish cotton, and to alter dying characteristics, texture and porosity of cellulose fibers.Type: GrantFiled: June 30, 1994Date of Patent: October 13, 1998Assignee: University of British ColumbiaInventors: Neil R. Gilkes, Douglas G. Kilburn, Robert C. Miller, Jr., Anthony Warren
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Patent number: 5817381Abstract: A process and materials are described in which highly refined celleuloise fibers are broken down into microfibers and further processed into compositions, films. coatings and solid materials which are biodegradable and even edible. The process for the formation of hardenable compositions may comprise:providing a composition comprising non-wood cellulose fiber, 36. mechanically reducing the size of the non-wood cellulose fiber to less than 2 mm, reducing the amount of binding of microfibers by lignin within said non-wood cellulose fibers present in said composition comprising cellulose fiber to form a first fiber product, providing pressure of at least 300 psi to said first fiber product while it is in the presence of a liquid, and removing said pressure within a time interval which will cause said cellulose fiber to break down into a second fiber product comprising microfibers in said liquid.Type: GrantFiled: November 13, 1996Date of Patent: October 6, 1998Assignees: Agricultural Utilization Research Institute, Regents of the University of MinnesotaInventors: Ling Chen, Rongsheng Roger Ruan, Jack Edgar Johnson, Paul Bradley Addis, Li Xu, Lun Yi
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Patent number: 5741901Abstract: The present invention relates to a modified cellulose ester containing unsaturated pendent groups which can be prepared by reacting a cellulose ester containing residual hydroxyl groups with, for example, maleic anhydride in acetic acid solvent with sodium acetate catalyst. The modified cellulose ester is not homopolymerizable but will copolymerize in the presence of vinyl crosslinking agents and a photoinitiator upon exposure to ultraviolet radiation. The modified cellulose ester is useful as a protective and/or decorative coating for wood, metal, plastics, paper, board, and other substrates, as well as an additive to printing inks, and as a nail polish. In addition, because of the propensity for the pendant carboxyl groups to form hydrophilic salts with amines, the modified cellulose esters can be formulated to be water-dispersible.Type: GrantFiled: November 16, 1995Date of Patent: April 21, 1998Assignee: Eastman Chemical CompanyInventors: Phillip Michael Cook, Robert Andrew Simm
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Patent number: 5705631Abstract: A laminar flow process for preparing cellulose diacetate fibers is disclosed. In the process, a precipitation-acid stream and an acid-dope stream are contacted in a zone having substantially laminar flow. The acid-dope stream is annularly disposed within and flows in the same direction as the precipitation-acid stream. The precipitation-acid stream has a temperature of 100.degree. to 200.degree. F. and comprises 25 to 35 percent by weight acetic acid and 75 to 65 percent by weight water. The acid-dope stream has a temperature in the range of 100.degree. to 200.degree. F. and comprised of 5 to 22 weight percent of cellulose diacetate having an inherent viscosity of at least 1.0, and 95 to 78 percent by weight of a mixture comprising 65 to 90 weight percent acetic acid and 35 to 10 weight percent water. The precipitation-acid stream has a linear flow greater than or equal to the linear flow of the acid-dope stream. The weight ratio of the precipitation-acid stream to the acid-dope stream is at least 9:1.Type: GrantFiled: December 15, 1995Date of Patent: January 6, 1998Assignee: Eastman Chemical CompanyInventor: Michael Orlando Malcolm
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Patent number: 5705632Abstract: A process for the preparation of a cellulose acetate film comprises the steps of: cooling a mixture of cellulose acetate and an organic solvent to -100.degree. to -10.degree. C.; warming the cooled mixture to 0.degree. to 50.degree. C. to dissolve the cellulose acetate in the organic solvent; casting the obtained solution on a support; and evaporating the organic solvent to form the cellulose acetate film. The cellulose acetate has an average acetic acid content in the range of 58.0 to 62.5%. The organic solvent is acetone.Type: GrantFiled: January 19, 1996Date of Patent: January 6, 1998Assignees: Fuji Photo Film Co., Ltd., Daicel Chemical Industries, Ltd.Inventors: Kazuhiro Shimoda, Masahiko Murayama, Hidekazu Yamazaki, Tohru Shibata, Shu Shimamoto, Hiroyuki Takemoto, Naoto Habu
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Patent number: 5674999Abstract: An improved process for surface treating water soluble cellulosic polymers with crosslinking agents to provide products which are more readily dispersible in cold water, and have longer viscosity delay times than can be achieved with polymers treated in low intensity mixers, such as ribbon blenders, comprising distributing the crosslinking agent using a continuous, high intensity mixer, followed by heating to facilitate surface crosslinking. This process also allows for a reduced level of crosslinking chemicals to be used.Type: GrantFiled: December 18, 1995Date of Patent: October 7, 1997Assignee: The Dow Chemical CompanyInventors: Michael R. Smith, Gary J. Schulz, Kenneth C. Reibert
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Patent number: 5663310Abstract: A cellulose acetate solution has cellulose acetate in a solvent. The cellulose acetate has an average acetic acid content in the range of 58.0 to 62.5%. In the first embodiment of the invention, the solvent is a mixture of acetone and another organic solvent. The organic solvent is an ether having 3 to 12 carbon atoms, a ketone having 4 to 12 carbon atom, an ester having 3 to 12 carbon atoms, or an alcohol having 1 to 6 carbon atoms. In the second embodiment, the solvent is the ether, the ketone or the ester. Processes for the preparation of the solution and a cellulose acetate film are also disclosed.Type: GrantFiled: January 19, 1996Date of Patent: September 2, 1997Assignees: Fuji Photo Film Co., Ltd., Daicel Chemical Industries, Ltd.Inventors: Kazuhiro Shimoda, Masahiko Murayama, Hidekazu Yamazaki, Tohru Shibata, Shu Shimamoto, Hiroyuki Takemoto, Naoto Habu
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Patent number: 5610233Abstract: This invention relates to aqueous coating compositions containing water soluble cellulose esters which are cross-linked with a resin system in the presence of an organic sulfonic acid catalyst for the formation of a film. The cellulose esters contain a low degree of substitution performed by solvolysis of cellulose esters of higher degree of substitution in the presence of a carboxylic acid catalyst.Type: GrantFiled: August 3, 1995Date of Patent: March 11, 1997Assignee: Eastman Chemical CompanyInventor: Mahendra K. Sharma
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Patent number: 5608051Abstract: This invention relates to a process for the acetylation of lignocellulosic materials (LM) by (a) bringing the LM into the intimate contact with an acetylating agent comprising acetic anhydride at a temperature from 70.degree.-140.degree. C. and (b) bringing the acetylated LM from step (a) into contact with a superheated chemical agent comprising acetic acid and/or anhydride at a temperature above 140.degree. C. so as to reduce the acetic acid or acetic anhydride content of the acetylated LM to below 10% by weight. LM's treated in this manner have excellent dimensional stability.Type: GrantFiled: October 13, 1994Date of Patent: March 4, 1997Assignee: BP Chemicals LimitedInventors: Helen L. Nelson, David I. Richards, Rune Simonson
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Patent number: 5597912Abstract: Process for reducing the degree of substitution of cellulose esters employing carboxylic acids as solvolysis promoters is disclosed. Exemplary cellulose esters are cellulose acetate, cellulose propionate, cellulose butyrate, cellulose acetate propionate, and cellulose acetate butyrate.Type: GrantFiled: March 4, 1994Date of Patent: January 28, 1997Assignee: Eastman Chemical CompanyInventors: Kevin J. Edgar, Charles M. Buchanan
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Patent number: 5532350Abstract: A solid composition of matter comprising one or more polysaccharides which has been cross-linked with either titanium or zirconium cross-linking agents is provided. The composition demonstrates absorbent properties and is useful in absorbent articles of manufacture. Also provided is a method for preparing the compositions.Type: GrantFiled: February 15, 1994Date of Patent: July 2, 1996Assignee: Rhone-Poulenc Inc.Inventors: Ian W. Cottrell, Animesh Goswami, Manjit S. Chowdhary
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Patent number: 5519130Abstract: Haloalkanoic acid impurities are decomposed in the presence of certain surfactants carboxymethyl cellulose or thioglycollic acids salts which may contain them as unconverted reactants by contacting them with dehalogenase enzyme.Type: GrantFiled: November 21, 1994Date of Patent: May 21, 1996Assignee: Zeneca LimitedInventors: David Byrom, Barbara A. Abbishaw
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Patent number: 5505830Abstract: Electron beam radiation of resin blends and compounds comprises in major part by weight of cellulose acetate accelerates the rate and increases the degree of biodegradation of the compounds and products made therefrom, and renders the same fully compostable, without sacrifice of physical properties.Type: GrantFiled: January 27, 1995Date of Patent: April 9, 1996Assignee: Planet Polymer Technologies, Inc.Inventor: Robert J. Petcavich
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Patent number: 5484913Abstract: A calcium-modified oxidized cellulose hemostat provides faster hemostasis than does either unmodified or sodium- or potassium-modified oxidized cellulose. The percentage by weight of calcium in the modified oxidized cellulose must be in a range between about 0.5 and about 4, in order to enhance hemostasis, while not interfering excessively with bioabsorbability. In a second embodiment, an oxidized cellulose hemostat is modified with both calcium and either sodium or potassium. The second embodiment may be used to deliver acid-sensitive materials.Type: GrantFiled: March 24, 1995Date of Patent: January 16, 1996Assignee: Johnson & Johnson Medical, Inc.Inventors: Reginald L. Stilwell, Elaine J. Whitmore, Lowell G. Saferstein
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Patent number: 5451672Abstract: A process for producing cellulose acetate from a hard, low-grade pulp sheet having a high sheet density on an industrial scale without impairing the acetylation reactivity of the pulp, characterized in that a pulp sheet having a sheet density of at least 0.5 g/cm.sup.3 is used as the cellulose material and the pulp sheet is disintegrated while feeding less than 40 parts by weight, based on 100 parts by weight (in terms of oven-dry weight) of the pulp sheet, of water into the disintegrating section of a disintegrator in the step of disintegrating the material. The present process is economically advantageous because the drying and humidity controlling steps are simplified due to the quantity of water to be fed being small.Type: GrantFiled: October 12, 1993Date of Patent: September 19, 1995Assignee: Daicel Chemical Industries, Ltd.Inventors: Hiroki Taniguchi, Yoshiaki Kaino, Ryota Iwata
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Patent number: 5449555Abstract: There are described filaments on the basis of a cellulose acetate soluble in acetone, the degree of polymerization (DP) of the cellulose acetate being between about 110 and 210 and the degree of substitution (DS) preferably between about 2.2 and 2.7. Optically isotropic spinning solutions can be obtained, the cellulose acetate concentration of which is about 35 to 47 mass-%. When such an optically isotropic spinning solution is spun, in particular by dry spinning, filaments are obtained in a profitable manner because the costs connected with the recovery of the acetone can be appreciably lowered, without impairing the desirable properties of the filaments, which are suitable in particular for the production of cigarette filter tow.Type: GrantFiled: January 21, 1994Date of Patent: September 12, 1995Assignee: Rhone-Poulenc Rhodia AktiengesellschaftInventors: Ties Karstens, Wolfgang Koppe, Joachim Schatzle, Gunter Maurer
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Patent number: 5371211Abstract: Cellulose esters of polycarboxylic acids, and their salts, such as the hydrogen cellulose ester of succinic acid, and the potassium salts thereof, are known to be useful in the preparation of conductive layers in composite such as photographic films. This invention comprises the discovery that such esters and salts provide improved conductive layers, if made from amorphous cellulose obtained by deacylating a material (such as cellulose acetate) using a lower alcohol as the deacylating agent, and an alkali metal alkoxide as the catalyst. Thus, the conductivity of potassium cellulose succinate (KCS) is improved, if made from a cellulose produced as described above. Furthermore, gelatin/KCS coating solutions made from improved KCS coating solutions of this invention have lower viscosities; this makes them much more suitable for roll coating, a support to be coated such as by a skim pan--air knife technique.Type: GrantFiled: December 4, 1990Date of Patent: December 6, 1994Assignee: Eastman Kodak CompanyInventor: Jan W. H. Faber
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Patent number: 5364935Abstract: Disclosed is a process comprising continuously flowing a composition through a hydrolysis zone so as to achieve a residence time distribution such that at least 81% of the area under the residence time distribution curve is within plus or minus 50% of the mean residence time. The composition comprises cellulose triacetate in the range of 5 to 30%, water in the range of 4 to 25%, and acetic acid in the range of 45 to 91%.Type: GrantFiled: April 23, 1993Date of Patent: November 15, 1994Assignee: Eastman Chemical CompanyInventors: Mark K. Cox, Tim J. Frederick
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Patent number: 5330642Abstract: Apparatus for filtering cellulose acetate solutions, including a backflush filter to effect filtration so as to avoid solvent losses and filtering aids that must be dumped, dilution means including solvent supply means for diluting the backflush liquid, separation means for eliminating solid insoluble components, and means for recycling backflush liquid freed from solids to a plant for producing new cellulose acetate spin solution.Type: GrantFiled: March 11, 1992Date of Patent: July 19, 1994Assignee: Lenzing AktiengesellschaftInventor: Walter Klein
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Patent number: 5328934Abstract: A process for recycling waste from the manufacture filtered cigarettes is disclosed herein. The process comprises the following steps: A waste stream from the manufacture of filtered cigarettes is provided. The waste stream includes tobacco, cellulose ester polymer, and paper. A substantial portion of the cellulose ester polymer is separated from this waste stream. This cellulose ester polymer is contacted with a sufficient volumne of fluid to extract contaminants therefrom. The fluid is under pressure and temperature conditions, such that the fluid is a supercritical or a near supercritical fluid.Type: GrantFiled: October 27, 1992Date of Patent: July 12, 1994Assignee: Hoechst Celanese CorporationInventor: David A. Schiraldi
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Patent number: 5294703Abstract: Provided is a novel improved process for the preparation of .alpha.-D-cellobiose octaacetate via the acetylative degradation of cellulose or cellulose acetate. The title compound is provided in high yield and quality in a facile one-pot process, amenable to large-scale synthesis.Type: GrantFiled: April 7, 1993Date of Patent: March 15, 1994Assignee: Eastman Kodak CompanyInventors: John A. Hyatt, Tony L. Sander, D. Mark Naylor, Bobby L. Bernard
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Patent number: 5244734Abstract: A process for producing fine cellulose particles, which comprises(1) mixing viscose with a water-soluble anionic polymeric compound or polyethylene glycol or its derivative to form a dispersion of fine particles of viscose,(2) (i) heating the dispersion or mixing it with a coagulating agent to thereby coagulate the viscose in the dispersion, and thereafter neutralizing it with an acid to form fine particles of cellulose, or (ii) coagulating and neutralizing the dispersion with an acid to form fine particles of cellulose, and(3) thereafter, separating the fine particles of cellulose from the mother liquor. The fine cellulose particles(a) are composed substantially of II-type cellulose,(b) have a crystallinity, of 5 to 35% by weight,(c) are composed substantially of particles of not more than 20 micrometers, and(d) have a sharp particle size distribution.Type: GrantFiled: January 15, 1988Date of Patent: September 14, 1993Assignees: Kanebo Ltd., Kanebo Rayon, Ltd.Inventors: Shigeru Okuma, Kanji Yamagishi, Masami Hara, Keizo Suzuki, Toshihiro Yamamoto
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Patent number: 5214137Abstract: A one step process for preparing cellulose diacetates from processed film having cellulose triacetate as a base. The process involves use of an organic acid such as acetic acid and a solvolysis agent such as an alkanol or water. Hydrogen and a hydrogenation catalyst are optionally employed. The process allows for a simple way of recycling a material that presently is not recycled to any appreciable extent.Type: GrantFiled: February 8, 1991Date of Patent: May 25, 1993Assignee: Eastman Kodak CompanyInventors: Alan K. Wilson, Fred D. Barlow, Jr.
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Patent number: 5202432Abstract: An assay for an analyte wherein sample is applied to a support capable of binding proteins by essentially only hydrogen bonding and fixed on the support. Analyte may be determined on the support by use of a suitable tracer. A preferred support is amphiphilic cellulose acetate. In an immunoassay, it is possible to determine analyte without use of a supported ("capture") antibody.Type: GrantFiled: February 4, 1991Date of Patent: April 13, 1993Assignee: ChemetronInventor: G. B. Del Campo
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Patent number: 5175276Abstract: An improved process for the production of cellulose ester fibrets wherein a thickened slurry of the fibrets in a liquid mixture of a solvent for the fibrets and a fibret non-solvent is contacted with saturated steam in the separation of the solvent from the fibrets.Type: GrantFiled: December 14, 1990Date of Patent: December 29, 1992Assignee: Hoechst Celanese CorporationInventors: Samuel S. McNair, Jr., David M. Gault
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Patent number: 5150723Abstract: Disclosed is a novel tobacco smoke filter material comprising a filter element such as cellulose acetate crimped tow having at least about 1 weight percent of micro acicular crystals of a compound such as sodium carbonate present on the surfaces of the filter element. Also disclosed is a process for preparation of such tobacco smoke filter material comprising immersing the filter element in a solution of the compound capable of forming the micro acicular crystals, followed by removing the filter element from the solution and removing residual liquid, thereby forming the novel tobacco smoke filter material.Type: GrantFiled: June 8, 1990Date of Patent: September 29, 1992Assignee: Eastman Kodak CompanyInventors: Benedict M. Lee, James E. Harris
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Patent number: 5142034Abstract: Process for reducing the degree of substitution of cellulose esters employing Lewis acids as solvolysis promoters is disclosed. Novel low degree of substitution cellulose esters produced by the invention process are also described.Type: GrantFiled: April 16, 1990Date of Patent: August 25, 1992Assignee: Eastman Kodak CompanyInventors: Michael Bellas, Charles M. Buchanan, Kevin J. Edgar, Ted C. Germroth, Alan K. Wilson
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Patent number: 5064949Abstract: Cellulose ester microparticles with unique properties are made by a process having the following steps:(a) dissolving a cellulose ester in a liquid comprising a solvent for the cellulose ester and a non-solvent for the cellulose ester, thereby forming a dope;(b) spheronizing the dope thereby forming fine droplets of the dope;(c) dropping the droplets for a finite amount of time; and(d) precipitating the droplets in a bath containing a precipitant.Type: GrantFiled: June 3, 1991Date of Patent: November 12, 1991Assignee: Hoechst Celanese CorporationInventors: Thomas L. Steiner, Kenneth A. Domeshek, William Stitt, Jesse L. Riley, Lance J. Deutsch
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Patent number: 5059659Abstract: Water insoluble polymers are treated to place on their exposed surfaces the pendant alkyl imidocarbonyl (amide) groups to impart a high degree of hydrophilicity to that surface. Nitrile-containing polymers or copolymers in the form of insoluble films, filters or membranes are treated to convert a substantial fraction of the surface nitrile groups into the corresponding amide by the use of hydrogen peroxide or concentrated acids. The surface is rendered hydrophilic and resistant to fouling to the extent that even proteins are not denatured thereupon. The surface may also be converted to substituted amides by subsequent reactions to impart to it other functionalities or to serve as the basis for coupling reactions. Other polymers capable of surface treatment to produce pendant amidocarbonyl groups include ones containing pendant esters which on cleavage of the oxygen-carbon bond give pendant alcohol groups.Type: GrantFiled: January 3, 1991Date of Patent: October 22, 1991Assignee: Harry P. GregorInventors: Harry P. Gregor, Alexander Burshteyn, Leonard T. Hodgins, John Kassotis, Edgar Samuelson
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Patent number: 5026841Abstract: Process for the preparation of finely divided porous cellulose in the form of essentially spherical particles by formation of a suspension, in which an organic solution of a cellulose ester of aromatic or aromatic-aliphatic carboxylic acids containing a C.sub.5 -C.sub.12 alkanol is stirred into an aqueous solution of an anionic surfactant, the solvent is removed and the particles are isolated and hydrolyzed under heterogeneous conditions. They are suitable as adsorbents in e.g. chromatographic processes.Type: GrantFiled: June 16, 1989Date of Patent: June 25, 1991Assignee: Ciba-Geigy CorporationInventors: Eric Francotte, Gabriele Baisch
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Patent number: 5024232Abstract: Novel radiopaqaue materials comprise heavy metal salts, such as bismuth and uraniuim salts complexed with a polymer. The metallic complexes which are permanent, nonleachable and have radiopacities at least equivalent to that of aluminum do not adversely affect the mechanical and physical properties of compositions. They are useful as medical and dental resins, in fabricating medical and dental appliances, prosthetic devices, radiation shielding devices and radiopaque polyester fabrics for clothing.Type: GrantFiled: July 25, 1989Date of Patent: June 18, 1991Assignee: The Research Foundation of State University of NYInventors: Johannes Smid, Israel Cabasso, Alan Obligin, H. Ralph Rawls
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Patent number: 5021201Abstract: Uniform discoid particles made of at least one member selected from the group consisting of a natural high molecular substance, a synthetic high molecular substance and an inorganic compound, wherein each particle has a diameter of 20 to 2,000 .mu.m and a thickness/diameter ratio of 1/2 to 1/50, and not less than 80% of the whole particles have a diameter within the range of 0.5 to 2 times the number average diameter, and a process for preparing the particles. The discoid particle of the present invention has a larger surface area and therefore has a high efficiency when employed in various uses such as a parent material for an ion exchange resin, a packing material for a chromatograph, a catalyst and an culture medium for cell culture in comparison with conventional spherical particle.Type: GrantFiled: November 9, 1989Date of Patent: June 4, 1991Assignee: Kanegafuchi Kagaku Kogyo Kabushiki KaishaInventors: Tamiyuki Eguchi, Michito Tsunomori
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Patent number: 4958014Abstract: A multi-cellular cellulose particle having a multiplicity of cells spaced from one another by cell membranes is described, which cells have a maximum inscribed sphere diameter of larger than 2 .mu.m. The cells have a continuous hole structure in which the cells communicate with one another through openings in the membranes separating two adjacent cells. The multi-cellular cellulose particle is prepared by forming drops of a solution of cellulose or a cellulose derivative, cooling the drops at a temperature lower than the solidification temperature of the solution to freeze the drops, and removing the solvent by extraction or nullifying the dissolving power of the solvent.Type: GrantFiled: August 9, 1988Date of Patent: September 18, 1990Assignee: Asahi Kasei Kogyo Kabushiki KaishaInventor: Junichi Shirokaze
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Patent number: 4888420Abstract: Microparticle of cellulose acetate and derivatives thereof characterized by being water soluble, having a large interior void space and having a plurality of open exterior surface pores. These water soluble microparticles can be loaded with a chemical selected from the group consisting of pharmaceuticals, dyes, flavorings, agriculturals, solid catalysts and fragrances.Type: GrantFiled: December 8, 1987Date of Patent: December 19, 1989Assignee: Celanese Fibers, Inc.Inventors: Thomas L. Steiner, Dana T. Minnick, Kenneth A. Domeshek, Donald H. Lester, Jr.
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Patent number: 4882392Abstract: Novel radiopaque materials comprise heavy metal salts, such as bismuth and uranium salts complexed with a polymer. The metallic complexes which are permanent, nonleachable and have radiopacities at least equivalent to that of aluminum do not adversely affect the mechanical and physical properties of compositions. They are useful as medical and dental resins, in fabricating medical and dental appliances, prosthetic devices, radiation shielding devices and radiopaque polyester fabrics for clothing.Type: GrantFiled: November 18, 1988Date of Patent: November 21, 1989Assignee: The Research Foundation of State University of New YorkInventors: Johannes Smid, Israel Cabasso, Alan Obligin, H. Ralph Rawls
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Patent number: 4837271Abstract: Curable mixtures based on(A) compounds containing hydroxyl groups,(B) curable compounds,(C) catalysts and(D) if appropriate a diluent and if appropriate further additives,in which compounds which are used as the curing compounds(B) are those which contain at least two enol ether groups of the formula (I) ##STR1## The mixtures according to the invention already cure rapidly at low temperatures and are particularly suitable for the production of shaped articles or coatings or as a constituent in lacquers.Type: GrantFiled: June 23, 1988Date of Patent: June 6, 1989Assignee: Hoechst AGInventor: Gerhard Brindopke
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Patent number: 4697007Abstract: The preparation of microcrystalline triacetylcellulose by acid-catalyzed acetylation of microcrystalline cellulose, perfluoroalkanesulfonic acids with 1 to 8 carbon atoms are used as the catalyst, resulting in a non-hazardous process and high yields of exceptionally high purity product, the latter being particularly suitable for chromatographic purposes, in particular for the chromatographic resolution of racemates.Type: GrantFiled: March 1, 1985Date of Patent: September 29, 1987Assignee: Merck Patent Gesellschaft mit beschrankter HaftungInventors: Georg Seitz, Rainer Wernicke
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Patent number: 4663447Abstract: Cellulose acetate is formed into porous, spherical particles, having an acetylation degree of 49 to 60%, a particle diameter of 0.05 to 10 mm, a sphericity of 0.7 or larger, a pore volume of 0.4 cc/g or larger and a collapsing strength of 9 kg or higher.Type: GrantFiled: January 23, 1985Date of Patent: May 5, 1987Assignee: Daicel Chemical Industries, Ltd.Inventors: Kazuhiro Yamazaki, Manabu Uchida
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Patent number: 4638057Abstract: A porous cellulose acetate molding containing an odoriferous substance is provided which is prepared by incorporating an odoriferous substance in a porous molding comprising cellulose acetate having a combined acetic acid of 50 to 58%, a pore volume of at least 0.65 cc/g and a collapsing strength of at least 10 kg. Said porous cellulose acetate may be one which is surface-saponified. Examples of the odoriferous substances include volatile substances such as insect repellents, antibacterials and mold inhibitors. Said porous cellulose acetate molding can adsorb the odoriferous substances fully without substantially changing its shape and persistently volatilize the substance for a long time.Type: GrantFiled: February 27, 1985Date of Patent: January 20, 1987Assignee: Daicel Chemical Industries, Ltd.Inventors: Shigeyuki Takahashi, Manabu Uchida, Kazuhiro Yamazaki
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Patent number: 4590265Abstract: The present invention provides a novel cellulosic material and a process for preparing the same. The cellulosic material is a carboxylated cellulose ester material having an acid number of at least about 5, an inherent viscosity of from about 0.01 to about 1.00 and wherein the anhydroglucose units thereof have ring substituents comprising by weight based on total polymer weight, of from about 0.05 to about 20% hydroxyl groups, from about 0.5 to about 44% acetyl groups, from 0 to about 54% butyryl groups, from 0 to about 47% propionyl groups, from about 0.4 to about 4.0% total carboxyl groups wherein from about 20% to about 100% of these carboxyl groups are non-saponifiable backbone, and wherein the material has a lactone level of from about 4.52.times.10.sup.-5 to about 6.13.times.10.sup.-4. The carboxylated cellulose esters of the present invention are prepared by reacting a cellulose ester with ozone at a temperature of about 25.degree. to 80.degree. C.Type: GrantFiled: April 18, 1985Date of Patent: May 20, 1986Assignee: Eastman Kodak CompanyInventors: Richard T. Bogan, Chung-Ming Kuo
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Patent number: 4548847Abstract: The invention comprises of an anionic polyelectrolyte hydrogel reversibly cross-linked with a polyvalent metal cation having a valence of at least two. This hydrogel may be combined with a removal agent for imparting delayed swelling characteristics when contacted with a water-containing fluid. The delayed swelling allows the water-containing fluid to penetrate or permeate the system before swelling is initiated, thereby providing enhanced wetting prior to the onset of swelling and alleviating gel blockage.Type: GrantFiled: January 9, 1984Date of Patent: October 22, 1985Assignee: Kimberly-Clark CorporationInventors: Gerard M. Aberson, Gerard J. F. Ring
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Patent number: 4549012Abstract: A new class of compounds, perfluoroacyl modified cellulose acetate polymers, has been synthesized. A novel method of preparation of these compounds is shown. It was discovered that these polymers can be used to form membranes having superior characteristics. The perfluoroacyl modification allows these polymers to be cast as ultrathin membranes resulting in improved gas flux rates while maintaining a high degree of selectivity, improved resistance to water, and the elimination of post treatment procedures. Furthermore these polymers can be spun as hollow fibers.Type: GrantFiled: August 13, 1984Date of Patent: October 22, 1985Inventor: Ashok K. Sharma
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Patent number: 4518433Abstract: The application discloses a process for making a polymeric powder which is readily dispersible in water to provide a composition useful for forming an enteric coating on pharmaceutical dosage forms and also a process for using the powder for its intended purpose.Type: GrantFiled: November 8, 1982Date of Patent: May 21, 1985Assignee: FMC CorporationInventors: Emanuel J. McGinley, Domingo C. Tuason, Jr.
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Patent number: 4501886Abstract: High strength, high modulus cellulose triacetate fibers are produced by spinning a 30-42% by weight solution of cellulose triacetate having an acetyl content of at least 42.5% and an inherent viscosity of at least 5 from a solvent mixture comprising trifluoroacetic acid and another solvent having a molecular weight of less than 160 in a mol ratio of 0.3-3.0 through an air gap into a coagulating bath. The fibers are optionally heat treated under tension or saponified to provide high strength high modulus regenerated cellulose fibers.Type: GrantFiled: August 1, 1983Date of Patent: February 26, 1985Assignee: E. I. Du Pont de Nemours and CompanyInventor: John P. O'Brien