Fine fibrous cellulose, dispersed solution, sheet, laminated sheet, laminate, and method for producing fine fibrous cellulose

Patent metadata

Field	Value
Publication number	US-12553185-B2
Application number	US-202117999308-A
Country	US
Kind code	B2
Filing date	May 19, 2021
Priority date	May 19, 2020
Publication date	Feb 17, 2026
Grant date	Feb 17, 2026

Abstract

It is an object of the present invention to provide fine fibrous cellulose capable of enhancing transparency and suppressing coloring, when the fine fibrous cellulose are processed into a dispersed solution or a sheet. The present invention relates to fine fibrous cellulose, in which the amount of substituents introduced is less than 0.5 mmol/g and the fiber width is 1 to 10 nm. Moreover, the present invention relates to a dispersed solution and a sheet, each of which comprises fine fibrous cellulose. Furthermore, the present invention relates to a method for producing fine fibrous cellulose, comprising: (A) removing at least a part of substituents from fine fibrous cellulose with a fiber width of 1000 nm or less having the substituents, and (B) performing a uniform dispersion treatment on the resulting fine fibrous cellulose after completion of the (A).

First claim

The invention claimed is:

1 . A sheet comprising fine fibrous cellulose, in which the amount of substituent introduced is less than 0.5 mmol/g and having a fiber width of 1 to 10 nm,
wherein the fine fibrous cellulose has a carbamide group, the haze is 5.0% or less, and the YI value at a thickness of 50 μm is 1.5 or less.

2 . The sheet according to claim 1 , wherein the substituent is an anionic group.

3 . The sheet according to claim 1 , wherein the substituent is a phosphorus oxoacid group, or substituent derived from the phosphorus oxoacid group.

4 . The sheet according to claim 1 , wherein when the sheet is heated at 160° C. for 6 hours, the YI increase percentage calculated according to the following equation is 1500% or less:
YI increase percentage (%)=(yellowness index of sheet after heating−yellowness index of sheet before heating)/yellowness index of sheet before heating×100,

wherein the yellowness index of the sheet is a yellowness index measured in accordance with JIS K 7373:2006.

5 . The sheet according to claim 1 , wherein the total light transmittance is 90.0% or more.

6 . The sheet according to claim 1 , wherein the surface roughness of at least one surface is 10 nm or less.

7 . A laminated sheet having a fiber layer and a resin layer, wherein
the fiber layer is the sheet according to claim 1 .

8 . The laminated sheet according to claim 7 , wherein the thickness of the fiber layer is 20 μm or more.

9 . The laminated sheet according to claim 7 , wherein the density of the fiber layer is 1.0 g/cm 3 or more.

10 . The laminated sheet according to claim 7 , wherein the resin layer is directly laminated on the fiber layer.

11 . The laminated sheet according to claim 7 , wherein the resin layer comprises at least one type selected from a polycarbonate resin, an acrylic resin and polyethylene terephthalate resin.

12 . The laminated sheet according to claim 7 , wherein the resin layer further comprises an adhesion aid.

13 . The laminated sheet according to claim 12 , wherein the adhesion aid is at least one type selected from an isocyanate compound and an organic silicon compound.

14 . The laminated sheet according to claim 13 , wherein the adhesion aid is an isocyanate compound, and the content of the isocyanate compound is 10 parts by mass or more and 40 parts by mass or less with respect to 100 parts by mass of the resin comprised in the resin layer.

15 . The laminated sheet according to claim 7 , wherein the YI value is 2.0 or less.

16 . The laminated sheet according to claim 7 , wherein the haze is 2.0% or less.

17 . A laminate comprising the laminated sheet according to claim 7 and an adherend.

Assignees

• Oji Holdings Corp

Inventors

• SUGIYAMA Ikue
• Matsubara Yusuke
• SHISHIDO Rina
• FUSHIMI Hayato
• Nishikori Yoshiharu

Classifications

• D21H21/26

  Agents rendering paper transparent or translucent · CPC title

• B32B2307/412

  Transparent · CPC title

• B32B2305/22

  Fibres of short length · CPC title

• B32B2262/062

  Cellulose fibres, e.g. cotton · CPC title

• B32B27/12

  next to a fibrous or filamentary layer · CPC title