Method for producing liquid developer
US-2020064752-A1 · Feb 27, 2020 · US
Hydroxypropyl methyl cellulose acetate succinate and method for producing the same
US11753483B2 · US · B2
| Field | Value |
|---|---|
| Publication number | US-11753483-B2 |
| Application number | US-202017083615-A |
| Country | US |
| Kind code | B2 |
| Filing date | Oct 29, 2020 |
| Priority date | Nov 1, 2019 |
| Publication date | Sep 12, 2023 |
| Grant date | Sep 12, 2023 |
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- Title
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Abstract
Official abstract text for this publication.
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.
First claim
Opening claim text (preview).
The invention claimed is: 1. A method for producing hydroxypropyl methyl cellulose acetate succinate comprising: 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 hydroxypropyl methyl cellulose acetate succinate; a precipitation step of precipitating the hydroxypropyl methyl cellulose acetate succinate by mixing the reaction product solution with water to obtain a suspension of the precipitated hydroxypropyl methyl cellulose acetate succinate; and a washing and recovering step of washing the hydroxypropyl methyl cellulose acetate succinate in the suspension and recovering the washed hydroxypropyl methyl cellulose acetate succinate. 2. The method for producing the hydroxypropyl methyl cellulose acetate succinate according to claim 1 , wherein a shape of each of the stirring blades is selected from the group consisting of a frame, a turbine, a ribbon, and an anchor wing.
Assignees
Inventors
Classifications
- C08B13/00Primary
Preparation of cellulose ether-esters · CPC title
- C08B3/26Primary
Isolation of the cellulose ester · CPC title
- C08B3/16Primary
Preparation of mixed organic cellulose esters {, e.g. cellulose aceto-formate or cellulose aceto-propionate} · CPC title
Cellulose; Derivatives thereof · CPC title
Stationary reactors having moving elements inside (B01J19/08, B01J19/26 take precedence) · CPC title
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- What does patent US11753483B2 cover?
- 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, t…
- Who is the assignee on this patent?
- Shinetsu Chemical Co
- What technology area does this patent fall under?
- Primary CPC classification C08B13/00. Mapped technology areas include Chemistry & Metallurgy.
- When was this patent published?
- Publication date Tue Sep 12 2023 00:00:00 GMT+0000 (Coordinated Universal Time) (B2). Legal status and post-grant events are not shown on this page.
- What related patents are in patentsdb?
- We list 3 related publications on this page (citations in our corpus or others sharing the same primary CPC).