Dissolution and processing of cellulose

Patent metadata

Field	Value
Publication number	US-10179823-B2
Application number	US-201615147739-A
Country	US
Kind code	B2
Filing date	May 5, 2016
Priority date	Nov 24, 2006
Publication date	Jan 15, 2019
Grant date	Jan 15, 2019

Abstract

The invention relates to a method for dissolving the components of gel forming materials suitable for use in wound care comprising the steps of admixing said components with an ionic liquid. The ionic liquid may be selected from the group of tertiary amine N-oxides, N,N-dimethyl formamide/nitrogen tetroxide mixtures, dimethyl sulphoxide/paraformaldehyde mixtures and solutions of limium chloride in N,N-dimethyl acetamide or N-methyl pyrrolidone.

First claim

The invention claimed is:

1. A solution consisting of a chemically modified cellulose dissolved in an ionic liquid wherein the chemically modified cellulose is carboxymethylcellulose, and the ionic liquid consists essentially of a liquid ionic compound which is liquid below 150 ° C., the liquid ionic compound having:
(i) a cation with a structure selected from:

 wherein
R 1 and R 2 are independently C 1 -C 6 alkyl or C 1 -C 6 alkoxyalkyl; and
R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , and R 9 are independently H, C 1 -C 6 alkyl, C 1 -C 6 alkoxyalkyl, or C 1 -C 6 alkoxy; and

(ii) an anion selected from halogen, pseudohalogen, or C 1 -C 6 carboxylate.

2. The solution of claim 1 , wherein the carboxymethylcellulose prior to dissolution comprises a powder.

3. The solution of claim 1 , wherein the dissolved carboxymethylcellulose is capable of being processed into a fiber, a nanofiber, a film, a coating, a foam, or a sponge.

4. The solution of claim 1 , wherein the dissolved carboxymethylcellulose is capable of being processed into a fiber.

5. The solution of claim 4 , wherein the fiber is sodium carboxymethyl cellulose fiber.

6. The solution of claim 5 , wherein the sodium carboxymethyl cellulose fiber has a degree of substitution of at least 0.05 carboxymethyl groups per glucose unit and a tenacity of at least 10 cN/tex.

7. The solution of claim 1 , wherein the carboxymethylcellulose is suitable for use in the treatment of wounds.

Assignees

• Convatec Technologies Inc

Inventors

• Kershaw David
• Adams Simon

Classifications

• C08B11/12

  substituted with carboxylic radicals {, e.g. carboxymethylcellulose [CMC]} · CPC title

• A61L15/28 Primary

  Polysaccharides or their derivatives {(A61L15/225 takes precedence)} · CPC title

• C08J2301/28

  Alkyl ethers · CPC title

• D10B2509/00

  Medical; Hygiene · CPC title

• D01D5/06

  Wet spinning methods {(D01D5/0046 takes precedence)} · CPC title