Cellulose fibers and process for producing the same, cellulose fiber assembly, and cellulose-fiber composite material

Patent metadata

Field	Value
Publication number	US-9309385-B2
Application number	US-201313972408-A
Country	US
Kind code	B2
Filing date	Aug 21, 2013
Priority date	Feb 21, 2011
Publication date	Apr 12, 2016
Grant date	Apr 12, 2016

Abstract

The present invention relates to cellulose fibers wherein a part of the hydroxyl groups of the cellulose have been substituted with at least one of a carboxy group and formyl group of 0.1 mmol/g or larger based on the weight of the cellulose fibers, and have been further substituted with a chemical modification group other than the carboxy and formyl groups.

First claim

The invention claimed is:

1. Cellulose fibers having a number-average fiber diameter of 18-25 nm and comprising cellulose,
wherein a part of the hydroxyl groups of the cellulose is substituted with at least one of a carboxy group and formyl group from 0.1 mmol/g to 1.0 mmol/g based on the weight of the cellulose fibers, and is further substituted with a chemical modification group other than the carboxy and formyl groups,
wherein the chemical modification group is an acyl group, and
wherein a degree of substitution with the chemical modification group is from 0.5 to 1.0.

2. The cellulose fibers of claim 1 , wherein the degree of substitution with the chemical modification group is from 0.53-0.91.

3. The cellulose fibers of claim 1 , wherein the degree of substitution with the chemical modification group is from 0.61-0.75.

4. The cellulose fibers of claim 3 , wherein the chemical modification group is an acetyl group.

5. The cellulose fibers of claim 1 , wherein the at least one of the carboxy group and formyl group has been introduced by an oxidation treatment.

6. The cellulose fibers of claim 1 , wherein the cellulose fibers are obtained by purifying a cellulose-comprising material and substituting part of the hydroxyl groups of the cellulose-comprising material with at least one of a carboxy group and formyl group and with the chemical modification group, to obtain the cellulose.

7. The cellulose fibers of claim 1 , wherein the chemical modification group is an acetyl group.

8. A cellulose fiber assembly, comprising:
the cellulose fibers of claim 1 .

9. A cellulose-fiber composite material, comprising:
the cellulose fibers of claim 1 ; and
a matrix material.

10. A process for producing cellulose fibers of claim 1 , the process comprising:
subjecting raw cellulose fibers to an oxidation treatment, a chemical modification treatment, and a fibrillation treatment.

Assignees

• Mitsubishi Chem Corp
• Oji Holdings Corp

Inventors

• Umemoto Tomokazu
• Ogita Naohide
• Shimizu Takanori
• Noishiki Yasutomo
• Nagatani Hiroyuki
• Banzashi Go

Classifications

• C08J2333/06

  of esters containing only carbon, hydrogen, and oxygen, the oxygen atom being present only as part of the carboxyl radical · CPC title

• C08B3/06

  Cellulose acetate {, e.g. mono-acetate, di-acetate or tri-acetate} · CPC title

• C08B15/04

  Carboxycellulose, e.g. prepared by oxidation with nitrogen dioxide · CPC title

• D01F2/24

  from cellulose derivatives · CPC title

• Y10T428/298

  Physical dimension · CPC title