There is provided a method for efficiently produce hydroxypropyl methyl cellulose acetate succinate (HPMCAS) having excellent flowability, where acetic acid in a reaction product mixture subjected to a wash and recovery step can be reduced. More specifically, there is provided a method for producing HPMCAS including an esterification step of esterifying hydroxypropyl methyl cellulose (HPMC) with acetic anhydride and succinic anhydride in acetic acid as a solvent to obtain a reaction product solution containing HPMCAS; a water addition step of adding water to the reaction product solution to obtain a water-added reaction product solution; an acetic acid removal step of removing at least a portion of both the solvent acetic acid and acetic acid derived from the acetic anhydride from the water-added reaction product solution to obtain a mixture having an acetic acid content reduced; and a wash and recovery step of washing the mixture and recovering the HPMCAS.

There is provided a method for efficiently produce hydroxypropyl methyl cellulose phthalate (HPMCP) having excellent flowability, where acetic acid in a reaction product mixture subjected to a wash and recovery step can be reduced. More specifically, there is provided a method for producing HPMCP including an esterification step of esterifying hydroxypropyl methyl cellulose (HPMC) with phthalic anhydride in acetic acid as a solvent to obtain a reaction product solution containing HPMCP; a water addition step of adding water to the reaction product solution to obtain a water-added reaction product solution; an acetic acid removal step of removing at least a portion of the acetic acid from the water-added reaction product solution to obtain a mixture having an acetic acid content reduced; and a wash and recovery step of washing the mixture and recovering the HPMCP.

There is provided a method for efficiently produce hydroxypropyl methyl cellulose phthalate (HPMCP) having excellent flowability, where acetic acid in a reaction product mixture subjected to a wash and recovery step can be reduced. More specifically, there is provided a method for producing HPMCP including an esterification step of esterifying hydroxypropyl methyl cellulose (HPMC) with phthalic anhydride in acetic acid as a solvent to obtain a reaction product solution containing HPMCP; a water addition step of adding water to the reaction product solution to obtain a water-added reaction product solution; an acetic acid removal step of removing at least a portion of the acetic acid from the water-added reaction product solution to obtain a mixture having an acetic acid content reduced; and a wash and recovery step of washing the mixture and recovering the HPMCP.

An aqueous composition which is useful for producing coatings and capsule shells comprises a) dispersed particles of an esterified cellulose ether comprising (i) groups of the formula —C(O)—R—COOA or (ii) a combination of aliphatic monovalent acyl groups and groups of the formula —C(O)—R—COOA, wherein R is a divalent hydrocarbon group and A is hydrogen or a cation, and the total degree of ester substitution is more than 0.70, and b) an esterified cellulose ether comprising aliphatic monovalent acyl groups and groups of the formula —C(O)—R—COOH, R being a divalent hydrocarbon group, wherein I) the degree of neutralization of the groups —C(O)—R—COOH is not more than 0.4, II) the total degree of ester substitution is from 0.03 to 0.70, and III) the esterified cellulose ether b) has a solubility in water of at least 2.0 weight percent at 2° C.

An aqueous composition which is useful for producing coatings and capsule shells comprises a) dispersed particles of an esterified cellulose ether comprising (i) groups of the formula —C(O)—R—COOA or (ii) a combination of aliphatic monovalent acyl groups and groups of the formula —C(O)—R—COOA, wherein R is a divalent hydrocarbon group and A is hydrogen or a cation, and the total degree of ester substitution is more than 0.70, and b) an esterified cellulose ether comprising aliphatic monovalent acyl groups and groups of the formula —C(O)—R—COOH, R being a divalent hydrocarbon group, wherein I) the degree of neutralization of the groups —C(O)—R—COOH is not more than 0.4, II) the total degree of ester substitution is from 0.03 to 0.70, and III) the esterified cellulose ether b) has a solubility in water of at least 2.0 weight percent at 2° C.

A process for recovering an esterified cellulose ether from a reaction product mixture obtained from a reaction of (a) a cellulose ether with (b) an aliphatic monocarboxylic acid anhydride or a di- or tricarboxylic acid anhydride or a combination of an aliphatic monocarboxylic acid anhydride and a di- or tricarboxylic acid anhydride, comprises the steps of (i) contacting the reaction product mixture with an aqueous liquid and precipitating the esterified cellulose ether from the reaction product mixture, and (ii) isolating the precipitated esterified cellulose ether from the mixture obtained in step (i), Tackiness of the esterified cellulose ether can be reduced when before or in step (i) a particulate silicon oxide or metal oxide is dispersed or suspended in the reaction product mixture, the aqueous liquid or a combination thereof.

There is provided a method for producing hydroxypropyl methyl cellulose acetate succinate (HPMCAS), including an esterification step of reacting hydroxypropyl methyl cellulose with an acetylating agent and a succinoylating agent in the presence of an aliphatic carboxylic acid in a kneader reactor equipped with two or more stirring blades rotating around their own axes and orbitally revolving, 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; and a washing and recovery step of washing the HPMCAS in the suspension and recovering the washed HPMCAS. Further, there is provided HPMCAS having yellowness at 20° C. of 15.0 or less, as determined in a 2% by mass solution of the HPMCAS in a mixed solvent of dichloromethane, methanol and water in a mass ratio of 44:44:10.

There is provided a method for producing hydroxypropyl methyl cellulose phthalate (HPMCP), including an esterification step of reacting hydroxypropyl methyl cellulose with a carboxybenzoylating agent in the presence of an aliphatic carboxylic acid in a kneader reactor equipped with two or more stirring blades rotating around their own axes and orbitally revolving, 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; and a washing and recovery step of washing the HPMCP in the suspension and recovering the washed HPMCP. Further, there is provided HPMCP having yellowness at 20° C. of 10.0 or less, as determined in a 10% by mass solution of the HPMCP in acetone.

There are provided low-substituted hydroxypropyl cellulose (L-HPC) having good compressibility and capping-prevention performance, and others. Specifically, provided are L-HPC having a hydroxypropoxy content of 5 to 16% by weight, a volume fraction of long fibrous particles of 20 to 40% and a volume fraction of short fibrous particles of 26 to 60% with the proviso that the latter is greater than the former; and a solid preparation containing the L-HPC. Also provided is a method for producing the L-HPC including the steps of: bringing powdery pulp having a length-weighted mean width of 10 to 25 m into contact with an alkali metal hydroxide solution, reacting the alkali cellulose with propylene oxide, and neutralizing the alkali metal hydroxide present in the reaction product with an acid to precipitate crude low-substituted hydroxypropyl cellulose in the absence of a step of dissolving a portion or all of the reaction product.

Provided is a nonaqueous binder for electrodes or separators, which is used in a lithium ion battery that has excellent cycle life characteristics at high temperatures. A nonaqueous binder for electrodes or separators of lithium ion batteries, which is obtained by complexing cellulose nanofibers and a thermoplastic fluororesin, and which is characterized in that the cellulose nanofibers have a fiber size (diameter) of from 0.002 m to 1 m (inclusive), a fiber length of from 0.5 m to 10 mm (inclusive), and an aspect ratio ((fiber length of cellulose nanofibers)/(fiber diameter of cellulose nanofibers)) of from 2 to 100,000 (inclusive).