An esterified cellulose ether is provided wherein the ester groups are phthalyl groups, the degree of substitution of phthalyl groups is from 0.02 to 0.18, the degree of neutralization of phthalyl groups is not more than 0.75, and the esterified cellulose ether has a solubility in water of at least 2.0 weight percent at 2 C.

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.

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.

Provided are low-substituted hydroxypropyl cellulose (L-HPC) having a hydroxypropoxy content of from 5 to 16% by weight, and having, on a basis of a dynamic image analysis to divide all particles into fine, spherical, and fibrous particles consisting of long and short fibrous particles, a volume fraction of the long fibrous particles of from 15 to 50% and a volume fraction of the short fibrous particles of from 23 to 60%; and a solid preparation containing the L-HPC. Also provided is a method for producing the L-HPC including the steps: bringing sheet-like or chip-like pulp having a length-weighted average fiber length of from 2.40 to 3.50 mm into contact with an alkali metal hydroxide solution, reacting the resulting alkali cellulose with propylene oxide, and dispersing the resulting reaction product in water containing an acid to partially dissolve it therein, followed by neutralization with an acid to precipitate crude L-HPC.

The present invention relates to a cellulose composite that makes separation and aggregation less likely to occur, and, more specifically, relates to a cellulose composite comprising cellulose and one or more types of water-soluble carboxymethyl cellulose wherein tan of an aqueous dispersion obtained by dispersing 1 mass % of the cellulose composite in ion-exchanged water is 0.6 or lower.

The present invention relates to a cellulose composite that makes separation and aggregation less likely to occur, and, more specifically, relates to a cellulose composite comprising cellulose and one or more types of water-soluble carboxymethyl cellulose wherein tan of an aqueous dispersion obtained by dispersing 1 mass % of the cellulose composite in ion-exchanged water is 0.6 or lower.

A method is used to prepare silver nanoparticles in the form of a silver nanoparticle cellulosic polymeric composite. A cellulosic polymer, organic solvent having a boiling point at atmospheric pressure of 100 C. to 500 C. and a Hansen parameter (.sub.T.sup.Polymer) equal to or greater than that of the cellulosic polymer, and a nitrogenous base are mixed to form a premix solution. Upon heating the premix solution to a temperature of at least 75 C., a solution of reducible silver ions is added that is equimolar or less in relation to the nitrogenous base. The weight ratio of reducible silver ions to the cellulosic polymer is 5:1 to 50:1. The resulting silver nanoparticle composite is cooled, isolated, and re-dispersed in an organic solvent, providing a non-aqueous silver-containing dispersion comprising the silver nanoparticle cellulosic polymeric composite.

A method is used to prepare silver nanoparticles in the form of a silver nanoparticle cellulosic polymeric composite. A cellulosic polymer, organic solvent having a boiling point at atmospheric pressure of 100 C. to 500 C. and a Hansen parameter (.sub.T.sup.Polymer) equal to or greater than that of the cellulosic polymer, and a nitrogenous base are mixed to form a premix solution. Upon heating the premix solution to a temperature of at least 75 C., a solution of reducible silver ions is added that is equimolar or less in relation to the nitrogenous base. The weight ratio of reducible silver ions to the cellulosic polymer is 5:1 to 50:1. The resulting silver nanoparticle composite is cooled, isolated, and re-dispersed in an organic solvent, providing a non-aqueous silver-containing dispersion comprising the silver nanoparticle cellulosic polymeric composite.

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.