Regioselectively substituted cellulose esters produced in a halogenated ionic liquid process and products produced therefrom

Patent metadata

Field	Value
Publication number	US-9777074-B2
Application number	US-201514858450-A
Country	US
Kind code	B2
Filing date	Sep 18, 2015
Priority date	Feb 13, 2008
Publication date	Oct 3, 2017
Grant date	Oct 3, 2017

Abstract

This invention relates to novel compositions comprising regioselectively substituted cellulose esters. One aspect of the invention relates to processes for preparing regioselectively substituted cellulose esters from cellulose dissolved in ionic liquids. Another aspect of the invention relates to the utility of regioselectively substituted cellulose esters in applications such as protective and compensation films for liquid crystalline displays.

First claim

That which is claimed is:

1. A cellulose ester comprising at least two different acyl groups, wherein at least one of said acyl groups comprises an aromatic compound, wherein said cellulose ester is regioselectively substituted with a RDS ratio of C6>C3>C2.

2. The cellulose ester of claim 1 , wherein said aromatic compound comprises a benzoate or a substituted benzoate.

3. The cellulose ester of claim 1 , wherein said aromatic compound comprises a benzoate.

4. The cellulose ester of claim 1 , wherein said cellulose ester has a degree of substitution from 1.6 to 2.9.

5. The cellulose ester of claim 1 , wherein at least one of said acyl groups comprises acetate or propionate.

6. The cellulose ester of claim 1 , wherein the ring RDS ratio of said cellulose ester for C6/C3 or C6/C2 is at least 1.05.

7. A film comprising said cellulose ester of claim 1 .

8. The film of claim 7 , wherein said film comprises a +C plate, a −C plate, a +A plate, or −A plate.

9. The film of claim 7 , wherein said film has an Rth in the range of −400 to +100 nm.

10. The film of claim 7 , wherein said film has an Rth in the range of −160 to +270 nm.

11. A compensation film comprising a regioselectively substituted cellulose ester comprising at least two different acyl groups, wherein at least one of said acyl groups comprises an aromatic compound, wherein the degree of substitution of said aromatic compound is greater at the C2 and C3 positions relative to the C6 position, wherein said film comprises a +C plate, a −C plate, a +A plate, or −A plate.

12. The film of claim 11 , wherein said aromatic compound comprises a benzoate or a substituted benzoate.

13. The film of claim 11 , wherein said aromatic compound comprises a benzoate.

14. The film of claim 11 , wherein said cellulose ester has a RDS ratio of C6>C3>C2.

15. The film of claim 11 , wherein said cellulose ester has a degree of substitution from 1.6 to 2.9.

16. The film of claim 11 , wherein at least one of said acyl groups comprises acetate or propionate.

17. The film of claim 11 , wherein said film has an Rth in the range of −400 to +100 nm.

18. The film of claim 11 , wherein said film has an Rth in the range of −160 to +270 nm.

Assignees

• Eastman Chem Co

Inventors

• Buchanan Charles Michael
• Buchanan Norma Lindsey
• Donelson Michael Eugene
• Gorbunova Maryna Grigorievna
• Kuo Thauming
• Wang Bin

Classifications

• C08J2301/10

  Esters of organic acids · CPC title

• C08B1/003

  Preparation of cellulose solutions, i.e. dopes, with different possible solvents, e.g. ionic liquids (solutions used in the manufacture of monocomponent artificial filaments or cellulose or derivatives thereof D01F2/02) · CPC title

• G02F2202/40

  Materials having a particular birefringence, retardation · CPC title

• B29D11/00788

  Producing optical films · CPC title

• G02F1/13363

  Birefringent elements, e.g. for optical compensation · CPC title