Abstract: There are provided a method for efficiently producing a water-soluble cellulose ether without using a special apparatus, and a novel water-soluble cellulose ether. More specifically, there are provided a method for producing a water-soluble cellulose ether including a first pulverization step of pulverizing a starting water-soluble cellulose ether to obtain a first pulverization product, and a first sieving step of sieving the first pulverization product by using a first sieve whose mesh surface is coated with an inorganic metal compound to obtain a first-sieve-passed water-soluble cellulose ether fraction; and a novel water-soluble cellulose ether.

Abstract: There are provided a porous water-soluble nonionic cellulose ether having an average pore size of 36 ?m or smaller and an average particle size of from 30 to 300 ?m; and a method for continuously producing said cellulose ether comprising the steps of: pulverizing a first water-soluble nonionic cellulose ether to obtain a first pulverized product, and sieving the pulverized product through a sieve having an opening of from 40 to 400 ?m to obtain a first residue-on-sieve and a first sieve-passing fraction, wherein a portion or all of the first residue-on-sieve containing particles having particle sizes smaller than and greater than the opening of the sieve is re-pulverized together with a second water-soluble nonionic cellulose ether in the step of pulverizing to obtain a second pulverized product, which is pulverized to obtain the cellulose ether as a second sieve-passing fraction containing the re-pulverized particles.

Abstract: There are provided a porous water-soluble nonionic cellulose ether having an average pore size of 36 ?m or smaller and an average particle size of from 30 to 300 ?m; and a method for continuously producing said cellulose ether comprising the steps of: pulverizing a first water-soluble nonionic cellulose ether to obtain a first pulverized product, and sieving the pulverized product through a sieve having an opening of from 40 to 400 ?m to obtain a first residue-on-sieve and a first sieve-passing fraction, wherein a portion or all of the first residue-on-sieve containing particles having particle sizes smaller than and greater than the opening of the sieve is re-pulverized together with a second water-soluble nonionic cellulose ether in the step of pulverizing to obtain a second pulverized product, which is pulverized to obtain the cellulose ether as a second sieve-passing fraction containing the re-pulverized particles.

Abstract: Provided is a method for producing a hydroxyalkyl alkyl cellulose having high thermal gel strength while suppressing a reduction in thermal gelation temperature. More specifically, provided is a method for producing a hydroxyalkyl alkyl cellulose including steps of: mixing cellulose pulp with a first alkali metal hydroxide solution to obtain alkali cellulose, reacting the alkali cellulose with an alkylating agent and a hydroxyalkylating agent to obtain a first reaction product mixture, adding a second alkali metal hydroxide solution to the first reaction product mixture without further adding any of alkylating and hydroxyalkylating agents to obtain a second reaction product mixture, and subjecting the second reaction product mixture to purification to obtain a hydroxyalkyl alkyl cellulose.

Abstract: Hydroxypropyl methyl cellulose having a high thermal gel strength even at a low viscosity is provided and utilized. Specifically provided is hydroxypropyl methyl cellulose having such properties that a 2% by weight aqueous solution of the hydroxypropyl methyl cellulose has a viscosity at 20° C. of 300 to 2,000 mPa·s and a storage elastic modulus at 85° C. of 2,000 to 4,500 mPa. Also provided is a food comprising the hydroxypropyl methyl cellulose. Further provided is a method for producing the hydroxypropyl methyl cellulose, the method comprising a step of depolymerizing, with an acid, high-viscosity hydroxypropyl methyl cellulose having such a property that a 2% by weight aqueous solution of the high-viscosity hydroxypropyl methyl cellulose has a viscosity at 20° C. of 70,000 to 100,000 mPa·s to obtain the hydroxypropyl methyl cellulose.

Abstract: There is provided a method for producing hypromellose phthalate (HPMCP), the method not requiring any special device, and facilitating removal of impurities. More specifically, there is provided a method for producing HPMCP, including an esterification step of esterifying hypromellose with a carboxybenzoylating agent in the presence of an aliphatic carboxylic acid to obtain a reaction product solution containing HPMCP; a precipitation step of precipitating the HPMCP by mixing the reaction product solution with water to obtain a suspension of the precipitated HPMCP; a neutralization step of neutralizing the suspension with a basic substance to obtain a neutralized suspension; and a washing step of washing the HPMCP contained in the neutralized suspension to obtain the washed HPMCP.

Abstract: There is provided a method for producing hypromellose acetate succinate (HPMCAS), the method not requiring any special device and facilitating removal of impurities. More specifically, there is provided a method for producing HPMCAS, including an esterification step of esterifying hypromellose with an acetylating agent and a succinoylating agent in the presence of an aliphatic carboxylic acid to obtain a reaction product solution containing HPMCAS; a precipitation step of precipitating the HPMCAS by mixing the reaction product solution with water to obtain a suspension of the precipitated HPMCAS; a neutralization step of neutralizing the suspension with a basic substance to obtain a neutralized suspension; and a washing step of washing the HPMCAS contained in the neutralized suspension to obtain the washed HPMCAS.

Abstract: Provided is a method for efficiently and continuously producing a cellulose ether containing a reduced amount of indissoluble component. Specifically, the method includes a contact step of bringing pulp into contact with an alkali metal hydroxide solution in the presence of a heat removal solvent to obtain alkali cellulose; a reaction step of subjecting the alkali cellulose to a reaction with an etherifying agent; a partial condensation step, after completion of the reaction, of partially condensing a gas present in a reaction vessel used for the reaction to separate the gas into gas and liquid components for returning some or all of the gas component to the contact step for reuse as some or all of the heat removal solvent; and a step of incinerating the liquid component and, when all of the gas component is not returned to the contact step, the remainder of the gas component.

Abstract: Provided is a method for producing low-substituted hydroxypropyl cellulose with less yellowing. More specifically, the method for producing purified low-substituted hydroxypropyl cellulose includes the steps of: reacting alkali cellulose and an etherifying agent to obtain a reaction mixture; dispersing the reaction mixture in water containing a portion of acetic acid necessary for neutralizing the total amount of the reaction mixture to neutralize a portion of the reaction mixture, and then completely neutralizing with the remaining acetic acid to cause precipitation, to obtain a slurry containing crude low-substituted hydroxypropyl cellulose; disintegrating a solid component in the slurry through a cutter pump, the solid component containing the crude low-substituted hydroxypropyl cellulose, and discharging the slurry containing the disintegrated solid component; washing the discharged slurry with water to obtain a cake of purified low-substituted hydroxypropyl cellulose; and drying the cake.

Abstract: Provided is a method for producing a hydroxyalkyl alkyl cellulose having high thermal gel strength while suppressing a reduction in thermal gelation temperature. More specifically, provided is a method for producing a hydroxyalkyl alkyl cellulose including steps of: mixing cellulose pulp with a first alkali metal hydroxide solution to obtain alkali cellulose, reacting the alkali cellulose with an alkylating agent and a hydroxyalkylating agent to obtain a first reaction product mixture, adding a second alkali metal hydroxide solution to the first reaction product mixture without further adding any of alkylating and hydroxyalkylating agents to obtain a second reaction product mixture, and subjecting the second reaction product mixture to purification to obtain a hydroxyalkyl alkyl cellulose.

Abstract: A method for producing a cellulose ether having a high viscosity while keeping the same degree of polymerization as that in the production of a shaped pulp without changing a raw material or production facility. More specifically, provided is a method for producing a cellulose ether including steps of: cutting or pulverizing pulp to obtain sheet-like, chip-like, or powdery cellulose pulp, wherein the pulp is formed in a form of roll whose surface layer on at least one of the circumferential side and the ends is removed, or in a form of bale whose surface layer on at least one side is removed; bringing the obtained cellulose pulp into contact with an alkali metal hydroxide solution to obtain alkali cellulose; reacting the alkali cellulose with an alkylating agent to obtain a reaction product mixture; and subjecting the reaction product mixture to purification to obtain the cellulose ether.

Abstract: Provided is a composition for forming a film, the composition not having completely dissolved hydroxypropyl methyl cellulose (HPMC), and enabling formation of the film having a uniform thickness by suppressing the viscosity increase of the composition around an immersion temperature of 50° C. More specifically provided is a composition for forming a film, the composition comprising hypromellose having methoxy group content of 28.0 to 30.0% by weight and hydroxypropoxy group content of 7.6 to 8.5% by weight, wherein a 2% by weight aqueous solution of the hypromellose provides a viscosity at 20° C. of 4.0 to 6.5 mPa·s, a 20% by weight dispersion of the hypromellose provides a viscosity at 50° C. of 2,000 to 11,000 mPa·s, and a 20% by weight aqueous solution of the hypromellose provides a gelation temperature of 54 to 57° C.; and a solvent.

Abstract: Provided are a method for producing a water-soluble cellulose ether having a low degree of polymerization and enhanced whiteness, and the like. The method includes the steps of: bringing a pulp powder having a multiplication product of less than 0.004 mm2 which is obtained by multiplying a number-average fiber length by a number-average fiber width, each measured with a Kajaani fiber length analyzer, into contact with an alkali metal hydroxide to obtain an alkali cellulose; reacting the alkali cellulose with an etherifying agent to obtain a crude water-soluble cellulose ether having a high degree of polymerization; purifying the crude water-soluble cellulose ether; drying the purified water-soluble cellulose ether; grinding the dried water-soluble cellulose ether into a water-soluble cellulose ether powder; and depolymerizing the water-soluble cellulose ether powder to obtain the water-soluble cellulose ether having a low degree of polymerization.

Abstract: An oil-in-water type composition which can provide a chewy texture both in a non-cooked state and a heated state and does not show water/oil separation, including: an alkyl cellulose, a 1% by mass aqueous solution of which has a viscosity at 20° C. of from 4,000 to 11,000 mPa·s when measured with a Brookfield type viscometer and a 1.5% by mass aqueous solution of which has a storage modulus G? (65° C.) at 65° C. of from 2,500 to 4,500 Pa; an edible oil or fat; and water. Also provided is a food using the alkyl cellulose.

Abstract: Provided is a method of stably producing a water-soluble nonionic cellulose ether powder having a high bulk density at low cost by adding a minimum amount of water. More specifically provided is a method for producing a water-soluble nonionic cellulose ether powder, comprising the steps of: reacting alkali cellulose with an etherifying agent to obtain a reaction product; washing and draining the reaction product to obtain a water-soluble nonionic cellulose ether; mixing the water-soluble nonionic cellulose ether with such an amount of water of 70° C. or higher as to make a water content of the water-soluble nonionic cellulose ether become 55 to 90% by weight to obtain a water-containing water-soluble nonionic cellulose ether having a water content of 55 to 90% by weight; cooling the water-containing water-soluble nonionic cellulose ether; and drying and pulverizing the cooled water-containing water-soluble nonionic cellulose ether.

Abstract: Hydroxypropyl methyl cellulose having a high thermal gel strength even at a low viscosity is provided and utilized. Specifically provided is hydroxypropyl methyl cellulose having such properties that a 2% by weight aqueous solution of the hydroxypropyl methyl cellulose has a viscosity at 20° C. of 300 to 2,000 mPa·s and a storage elastic modulus at 85° C. of 2,000 to 4,500 mPa. Also provided is a food comprising the hydroxypropyl methyl cellulose. Further provided is a method for producing the hydroxypropyl methyl cellulose, the method comprising a step of depolymerizing, with an acid, high-viscosity hydroxypropyl methyl cellulose having such a property that a 2% by weight aqueous solution of the high-viscosity hydroxypropyl methyl cellulose has a viscosity at 20° C. of 70,000 to 100,000 mPa·s to obtain the hydroxypropyl methyl cellulose.

Abstract: Provided is a composition for forming a film, the composition not having completely dissolved hydroxypropyl methyl cellulose (HPMC), and enabling formation of the film having a uniform thickness by suppressing the viscosity increase of the composition around an immersion temperature of 50° C. More specifically provided is a composition for forming a film, the composition comprising hypromellose having methoxy group content of 28.0 to 30.0% by weight and hydroxypropoxy group content of 7.6 to 8.5% by weight, wherein a 2% by weight aqueous solution of the hypromellose provides a viscosity at 20° C. of 4.0 to 6.5 mPa·s, a 20% by weight dispersion of the hypromellose provides a viscosity at 50° C. of 2,000 to 11,000 mPa·s, and a 20% by weight aqueous solution of the hypromellose provides a gelation temperature of 54 to 57° C.; and a solvent.

Abstract: There are provided a porous water-soluble nonionic cellulose ether having an average pore size of 36 ?m or smaller and an average particle size of from 30 to 300 ?m; and a method for continuously producing said cellulose ether comprising the steps of: pulverizing a first water-soluble nonionic cellulose ether to obtain a first pulverized product, and sieving the pulverized product through a sieve having an opening of from 40 to 400 ?m to obtain a first residue-on-sieve and a first sieve-passing fraction, wherein a portion or all of the first residue-on-sieve containing particles having particle sizes smaller than and greater than the opening of the sieve is re-pulverized together with a second water-soluble nonionic cellulose ether in the step of pulverizing to obtain a second pulverized product, which is pulverized to obtain the cellulose ether as a second sieve-passing fraction containing the re-pulverized particles.

Abstract: The invention is a method for efficiently preparing alkali cellulose having a uniform alkali distribution therein. More specifically, the invention is a method for preparing alkali cellulose comprising steps of bringing pulp into continuous contact with an alkali metal hydroxide solution in a bucket conveyor type contactor to generate a contact mixture, and draining the contact mixture; a method for preparing a cellulose ether comprising use of the alkali cellulose thus prepared; and an apparatus for preparing alkali cellulose comprising a bucket conveyor contactor comprising at least one inlet port for introducing pulp and an alkali metal hydroxide solution at one end and at least one outlet port for discharging a contact mixture wherein the pulp and the alkali metal hydroxide solution can be moved from one end to the other end while bringing them into contact with each other to generate the contact mixture; and a drainer for separating a cake from the contact mixture discharged from the outlet port.

Abstract: The invention is a method for efficiently preparing alkali cellulose having a uniform alkali distribution therein. More specifically, pulp and an excess alkali metal hydroxide solution are introduced continuously in a screw conveyor type contactor and brought into contact with each other in the screw conveyor type reactor. By changing at least one factor selected from the group consisting of a rotation speed of the screw conveyor, a screw pitch and a length of immersion zone, a ratio of an alkali to cellulose in the alkali cellulose obtained by draining is controlled. The alkali cellulose thus obtained is etherified into the corresponding cellulose ether.