Esterified cellulose ethers which have i) as ester groups aliphatic monovalent acyl groups or groups of the formula C(O)RCOOA or a combination of aliphatic monovalent acyl groups and groups of the formula C(O)RCOOA, wherein R is a divalent aliphatic or aromatic hydrocarbon group and A is hydrogen or a cation, and ii) a content of not more than 0.85 weight percent acetone-insoluble esterified cellulose ether particles, when the esterified cellulose ether is present in a mixture of 12.5 weight parts of esterified cellulose ether and 87.5 weight parts of acetone at 21 C., the weight percent acetone-insoluble esterified cellulose ether particles being based on the total weight of the esterified cellulose ether, wherein iii) not more than 14 percent of the acetone-insoluble esterified cellulose ether particles have a particle size of more than 90 micrometers.

There is provided a method for producing hypromellose phthalate (HPMCP) which exhibits an excellent solubility when dissolved in a solvent, while suppressing formation of undissolved matter. More specifically, there is provided a method for producing HPMCP, including an esterification step of esterifying hypromellose dissolved in glacial acetic acid with phthalic anhydride in the presence of sodium acetate at a temperature of from 75 to 100 C. to obtain a reaction product solution; a cooling step of cooling the reaction product solution to 70 C. or lower; and a precipitation step of mixing the cooled reaction product solution with water of from 0 to 40 C. to obtain a suspension of precipitated HPMCP.

There is provided a method for producing hypromellose phthalate (HPMCP) which exhibits an excellent solubility when dissolved in a solvent, while suppressing formation of undissolved matter. More specifically, there is provided a method for producing HPMCP, including an esterification step of esterifying hypromellose dissolved in glacial acetic acid with phthalic anhydride in the presence of sodium acetate at a temperature of from 75 to 100 C. to obtain a reaction product solution; a cooling step of cooling the reaction product solution to 70 C. or lower; and a precipitation step of mixing the cooled reaction product solution with water of from 0 to 40 C. to obtain a suspension of precipitated HPMCP.

An aqueous composition useful for producing capsules shells comprises a) at least one dispersed esterified cellulose ether comprising (i) groups of the formula C(O)RCOOA or (ii) a combination of aliphatic monovalent acyl groups and groups of the formula C(O)RCOOA, wherein R is a divalent aliphatic or aromatic hydrocarbon group and A is hydrogen or a cation, and b) from 0.05 to 20 percent of at least one salt of a fatty acid, based on the weight of the dispersed esterified cellulose ether, wherein the median particle size, d50, of the dispersed esterified cellulose ether particles is up to 7 micrometers, such median particle size (d50) being the size at which 50 mass percent of the particles have a smaller equivalent diameter and 50 mass percent have a larger equivalent diameter.

An aqueous composition useful for producing capsules shells comprises a) at least one dispersed esterified cellulose ether comprising (i) groups of the formula C(O)RCOOA or (ii) a combination of aliphatic monovalent acyl groups and groups of the formula C(O)RCOOA, wherein R is a divalent aliphatic or aromatic hydrocarbon group and A is hydrogen or a cation, and b) from 0.05 to 20 percent of at least one salt of a fatty acid, based on the weight of the dispersed esterified cellulose ether, wherein the median particle size, d50, of the dispersed esterified cellulose ether particles is up to 7 micrometers, such median particle size (d50) being the size at which 50 mass percent of the particles have a smaller equivalent diameter and 50 mass percent have a larger equivalent diameter.

A process for making esterified cellulose ethers which have i) a combination of aliphatic monovalent acyl groups and groups of the formula C(O)RCOOA wherein R is a divalent aliphatic or aromatic hydrocarbon group and A is hydrogen or a cation, ii) a weight average molecular weight M.sub.w of from 80,000 Dalton to 350,000 Dalton, iii) a Polydispersity M.sub.w/M.sub.n of from 1.3 to 4.1, and iv) a viscosity of up to 4.0 mPa.Math.s, measured as a 2.0 wt % solution of the esterified cellulose ether in 0.43 wt % aqueous NaOH at 20 C., are useful as enteric polymers for pharmaceutical dosage forms.

A process for making esterified cellulose ethers which have i) a combination of aliphatic monovalent acyl groups and groups of the formula C(O)RCOOA wherein R is a divalent aliphatic or aromatic hydrocarbon group and A is hydrogen or a cation, ii) a weight average molecular weight M.sub.w of from 80,000 Dalton to 350,000 Dalton, iii) a Polydispersity M.sub.w/M.sub.n of from 1.3 to 4.1, and iv) a viscosity of up to 4.0 mPa.Math.s, measured as a 2.0 wt % solution of the esterified cellulose ether in 0.43 wt % aqueous NaOH at 20 C., are useful as enteric polymers for pharmaceutical dosage forms.

A cellulose ether acetate phthalate is provided, wherein the degree of substitution of phthalyl groups is from 0.02 to 0.25, the degree of neutralization of phthalyl groups is not more than 0.5, the degree of substitution of acetyl groups is from 0.02 to 0.40, and the total degree of substitution of phthalyl and acetyl groups is not more than 0.50. The cellulose ether acetate phthalate has a solubility in water of at least 2.0 weight percent at 2 C.

A resin composition containing: a cellulose ester having at least two types of acyl groups; and an esterified starch.

An all-solid-state secondary battery includes a positive electrode active substance layer; a negative electrode active substance layer; and an inorganic solid electrolyte layer, in which at least one of the positive electrode active substance layer, the negative electrode active substance layer, or the inorganic solid electrolyte layer contains an inorganic solid electrolyte having conductivity of ions of metal belonging to Group 1 or 2 of the periodic table and a cellulose polymer.