An object of the present invention is to provide a method for producing a polysaccharide derivative in which the use of a reagent such as an acid catalyst is not needed and a reaction can be smoothly progressed without causing any side reactions. A method for producing a polysaccharide derivative of the present invention includes a step of dissolving a raw material including a polysaccharide in at least one ionic liquid having an anion which is a non-carboxylate anion and reacting the raw material with an acyl group donor, a conjugate acid of the anion having a pKa of 4 or higher in vacuum.

An object of the present invention is to provide a method for producing a polysaccharide derivative in which the use of a reagent such as an acid catalyst is not needed and a reaction can be smoothly progressed without causing any side reactions. A method for producing a polysaccharide derivative of the present invention includes a step of dissolving a raw material including a polysaccharide in at least one ionic liquid having an anion which is a non-carboxylate anion and reacting the raw material with an acyl group donor, a conjugate acid of the anion having a pKa of 4 or higher in vacuum.

A process for acylation of a solid material (3, 9) bearing reactogenic hydroxyls includes at least one fatty acid chloride (1) is distributed at least on the surface of the solid material (3, 9) using a distributor device (2) having an application surface. At least one fatty acid chloride (1) is distributed at least on the surface of the solid material (3, 9) is heated at a temperature, referred to as acylation temperature, below the vaporization temperature of the at least one fatty acid chloride (1), so as to enable an acylation of the solid material (3, 9). A stream of a gaseous composition (6) is directed over the said solid material (3, 9) at the acylation temperature, so as to entrain at least one portion of gaseous hydrochloric acid (7) formed by the acylation reaction

The application surface of the distributor device (2) is a velvet provided with velvet filiform elements that are suitable for taking up the at least one fatty acid chloride (1) by contact with the at least one fatty acid chloride, and releasing at least one fatty acid chloride by bringing the filiform elements of the velvet into contact with the solid material (3, 9). The distribution step (12, 14) is carried out so as to distribute over the solid material (3, 9) an amount of the at least one fatty acid chloride (1) of between 20 mg/m.sup.2 and 1 g/m.sup.2 surface area of the solid material (3, 9).

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.

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.

According to an example aspect of the present invention, there is provided a use of molar mass controlled cellulose in injection molding, extrusion and three dimensional printing applications.

According to an example aspect of the present invention, there is provided a use of molar mass controlled cellulose in injection molding, extrusion and three dimensional printing applications.

According to an example aspect of the present invention, there is provided a use of molar mass controlled cellulose in injection molding, extrusion and three dimensional printing applications.

According to an example aspect of the present invention, there is provided a use of molar mass controlled cellulose in injection molding, extrusion and three dimensional printing applications.

Cellulose derivative particles including an alkoxy group having 2 or more carbons or an acyl group having 3 or more carbons, wherein the cellulose derivative particles have an average particle size of 80 nm or greater and 100 μm or less, a sphericity of 70% or greater and 100% or less, and a surface smoothness of 80% or greater and 100% or less; and a total substitution degree of the cellulose derivative is 0.7 or greater and 3 or less.