Class 536/70 - With pretreatment process

Subclass of Class 536 - Organic compounds -- part of the class 532-570 series
Definition: Processes in which cellulose undergoes a physical or chemical
No. of patents: 33
Last issue date: 04/04/2006

Number	Title	Issue Date
7022837	Cellulose ethers and method of preparing the same The present inventors have discovered that the solution rheology of cellulose ethers prepared from cellulose pulp is altered by mercerizing and recovering cellulose pulp before preparing the cellulose ethers. For example, the solution viscosity of carboxymethyl cell...	04/04/2006
6835828	Alkylene oxide modified hardwood cellulose Disclosed is a process for producing reactive cellulose for use in the manufacture of cellulose acetate having superior clarity by mercerizing hardwood cellulosic material and reacting it with an hydroxyalkylating agent to a degree of molar substitution ranging from...	12/28/2004
6683174	Cellulose triacetates and methods for producing the cellulose triacetates The present invention provides a cellulose triacetate which exhibits a satisfactory filtration performance Thus, the present invention provides a cellulose triacetate whose occlusion constant (K) determined by the following method is 70 or less. Method: t...	01/27/2004
6407224	Catalytic system for cellulose acylation process for producing said catalytic system, and for its practical application A catalytic system for cellulose acylation includes an adduct of sulfuric acid with N,N-dimethylacetamide, free sulfuric acid or free N,N-dimethylacetamide with the following mole ratio of the components: adduct:1.0; free sulfuric acid, max:0.49; or free ...	06/18/2002
6103891	Method for the synthesis of nucleotide or oligonucleotide phosphoramidites The present invention presents novel methods for recovery of phosphoramidites from the waste products of oligonucleotide synthesis. The methods include reacting a trihalophenoxydihalophosphorane with a H-phosphonate in the presence of an amine....	08/15/2000
6083498	Chemical attractants for yellowjackets and paper wasps Compositions and lures are described which provide vapor blends of acetic acid and one or more compounds selected from the group consisting of isobutanol, racemic 2-methyl-1-butanol, S-(-)-2-methyl-1-butanol, 2-methyl-2-propanol, heptyl butyrate, and buty...	07/04/2000
5990304	Cellulose acetate excellent in physical strength, and process for production thereof An object of the invention is to obtain cellulose acetate with improved physical properties, particularly film strength arid improved flexibility of the molded product. Cellulose acetate wherein average degree of acetylation is not less than 59%, viscosit...	11/23/1999
5962677	Cellulose acetate with high moldability and process for production thereof 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...	10/05/1999
5929229	Direct process for the production of cellulose esters 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 carboxamid...	07/27/1999
5928613	Apparatus for acetylating cellulose 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 compo...	07/27/1999
5914397	Cellulose acetate excellent in physical strength, and process for production thereof 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%, visco...	06/22/1999
5869646	Method and apparatus for acetylating cellulose 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 compo...	02/09/1999
5821359	Acetylation of lignocellulosic fibres 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° C. and a pressure of 100-150 kPa wherein raw or substantially raw LFs are treated with...	10/13/1998
5770726	Process for preparing a cellllose acetoacetate alkanoates The present invention relates to a process for preparing a substituted cellulose acetoacetate alkanoate without using a carboxamide/lithium chloride solvent system. The process involves contacting cellulose in a carboxylic acid diluent with an acetylating...	06/23/1998
5750677	Direct process for the production of cellulose esters The present invention relates to a process for preparing cellulose esters having a total DS/AGU of 0.1 to 3.0, said process comprising contacting the following: (i) a cellulose material, (ii) a solubilizing amount of a solvent system comprising a carboxamide ...	05/12/1998
5723600	Method for incorporating cellulose esters into cellulose by immersing cellulose in an acid-dope solution A method for treating cellulose with cellulose ester for use in various paper products involves reacting cellulose and an acid anhydride to form a cellulose ester-carboxylic acid solution. Acetic anhydride may be used as the acid anhydride, and a cellulos...	03/03/1998
5674999	Process for preparing readily dispersible water-soluble cellulosic polymers 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 l...	10/07/1997
5608050	Process for the manufacture of cellulose acetate The specification discloses a process for the manufacture of cellulose acetate. The process reacts, at a temperature suitable for acetylation, an acetic acid activated pretreated cellulose raw material containing 100 parts cellulose by dry weight, and 0.5...	03/04/1997
5451672	Process for producing cellulose acetate 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 ...	09/19/1995
5378828	Process for preparing soluble alkali metal salts of cellulose sulfate using chlorosulfuric acid and pyridine The present invention provides a process for the preparation of water soluble alkali metal salts of cellulose sulfate having a degree of substitution ranging from 1 to 3 and viscosity of 1 percent aqueous solution in excess of 20 centipoises (cps). The pr...	01/03/1995
5371207	Pressure pretreatment for improving the acetylation of cellulose A novel method has been discovered for the pretreatment of cellulose with acetic acid and acetic anhydride under pressure, resulting in uniformly activated cellulose fibers. The improved process for producing cellulose diacetate comprises the steps of: (1...	12/06/1994
5294703	Process for preparing ଱-D-cellobiose octaacetate Provided is a novel improved process for the preparation of ଱-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 ...	03/15/1994
5244945	Synthesis of plastics from recycled paper and sugar cane A method is provided for preparing a cellulose ester plastic composition from waste paper (e.g. recycled paper) and/or sugar cane bagasse. The paper or bagasse is reacted with an acid anhydride in the presence of a catalyst to esterify some of the hydroxy...	09/14/1993
5150723	Process for the production of tobacco smoke filters 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 fi...	09/29/1992
5150721	Tobacco smoke filter material and process for production thereof Disclosed is a novel process of preparing tobacco smoke filter material, wherein an acidic compound such as citric acid is dissolved in a cellulose acetate spinning solution prior to spinning the filaments of the filter material....	09/29/1992
5141006	Tobacco smoke filter material and process for production thereof Disclosed is a novel process of preparing tobacco smoke filter material, wherein an acidic compound such as citric acid is dissolved in a cellulose acetate spinning solution (dope) prior to spinning the filaments of the filter material....	08/25/1992
5114535	Process for the production of cellulose acetate from wood pulp A process for making cellulose acetate from wood pulp takes wet wood pulp and instead of converting it into dry pulp sheet which is the usual feedstock for acetate, dries and mechanically separates the pulp into a cellulose flock using a pin mill through ...	05/19/1992
5036900	Method for acetylating shredded cellulosic Cellulosic sheet material is processed in preparation for esterification for example acetylation to produce cellulose acetate, by treating the sheet material with water and then feeding the wetted material into a machine that simultaneously shreds and dri...	08/06/1991
4480090	Process for esterification of cellulose using as the catalyst the combination of sulfuric acid, phosphoric acid and a hindered aliphatic alcohol The present invention relates to a method of preparing lower fatty acid esters of cellulose which comprises esterifying at a temperature of between about 75° C. and about 110° C. a cellulose compound having esterifiable hydroxyl groups with an esterifyi...	10/30/1984
4399275	Preparation of highly reactive cellulose Highly reactive cellulose is prepared by mercerizing cellulosic material and reacting it with an hydroxyalkylating agent to a degree of substitution ranging from 0.05 to 0.3, said degree of substitution being short of rendering the cellulose appreciably s...	08/16/1983
4385172	Prevention of hornification of dissolving pulp Heat treatment of never-dried dissolving pulps prior to drying prevents or retards the hornification and consequent decrease in esterification reactivity which normally occurs on drying of untreated pulps....	05/24/1983
4336370	Process for activating cellulose pulp to improve ease of esterification Treatment of dissolving pulp derived from wood with small quantities of C2 -C18 carboxylic acids and subsequent storage of the treated pulp, under conditions where little acid evaporation can occur, for periods of about two hours or ...	06/22/1982
4162359	Production of cellulose acetate Cellulose acetate is produced by subjecting highly purified cellulosic dissolving pulp to a bleaching sequence including at least one alkaline extraction stage and acetylating the bleached pulp to convert the pulp to cellulose acetate. The yellowness inde...	07/24/1979

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Class 536/70 - With pretreatment process