Fluorinated amine products

• US 5,929,201 A
• Filed: 05/20/1997
• Issued: 07/27/1999
• Est. Priority Date: 03/29/1996
• Status: Expired due to Fees

• Current Assignee: Elsicon Incorporated
• Original Assignee: Elsicon Incorporated
• Inventors: Gibbons, Wayne M., Shannon, Paul J., Sun, Shao-Tang
• Primary Examiner(s): HAMPTON HIGHTOWER, PATRICIA
• Application Number:
  US08/859,403
• Time in Patent Office: 798 Days
• Field of Search: 528/353, 528/174, 528/125, 528/128, 528/170, 528/171, 528/172, 528/173, 528/179, 528/183, 528/185, 528/188, 528/220, 528/229, 528/350, 359/44, 359/90, 350/345, 350/341, 350/346, 350/349, 350/350 R, 350/350 S, 350/351
• US Class Current: 528/353
• CPC Class Codes: C08G 73/10 Polyimides; Polyester-imides; Polyamide-imides; Polyamide acids or similar polyimide precursors
• CPC Class Codes: C08G 73/1039 comprising halogen-containing substituents
• CPC Class Codes: C08G 73/1085 Polyimides with diamino moieties or tetracarboxylic segments containing heterocyclic moieties
• CPC Class Codes: G02F 1/133723 Polyimide, polyamide-imide
• CPC Class Codes: G02F 1/133788 by light irradiation, e.g. linearly polarised light photo-polymerisation

Abstract

The present invention relates to amine compositions and the preparation of polyimides. The polyimides can be used for inducing alignment of a liquid crystal medium with polarized light and liquid crystal display elements.

Claims

1. A polyamic acid which is the reaction product of an amine component comprising a monoamine of the formula:

space="preserve" listing-type="equation">X.sub.1 --(CF.sub.2).sub.p --(CH.sub.2).sub.n --X--Ar--NH.sub.2

wherein Ar is selected from the group consisting of ##STR42## X is selected from the group consisting of --O--, --S-- and --NR-- and a covalent bond, wherein R is H or a C₁ to C₄ hydrocarbon, X1 is selected from HE and F, n is 0-4 and p is 6-20, wherein when X is --S-- or a covalent bond, n is 1-4 and wherein the monoamine comprises about from 0.1 to 15 mol % of the amine component;

at least one diamine; and

at least one tetracarboxylic dianhydride;

wherein the monamine comprises about from 0.01 to 5 mol % of the main component.

2. A polyamic acid of claim 1 wherein X is selected from the group --O-- and --NR-- and n is 1-4.

3. A polyamic acid of claim 1 wherein the tetracarboxylic dianhydride is a diaryl ketone tetracarboxylic dianhydride of the general formula ##STR43## wherein X₂ is independently selected from the group 11, CL, F, Br, R₁ and R₁ O--, wherein R₁ is independently selected from C₁ -C₃ perflourinated alkyl chain, C₁ -C₃ partially fluorinated alkyl chain and C₁ -C₈ hydrocarbon chain;

m is 1 or 0; and

Z is selected from the group --S--, --O--, --SO₂ --, --CH₂, --C((CF₃)₂, --C(O)--, --CH₂ CH₂ --, --NR-- and a covalent bond, wherein R is a C₁ -C₄ hydrocarbon chain.

4. A polyamic acid of claim 3 wherein the tetracarboxylic dianhydride is selected from 3,3'"'"'4,4'"'"'-benzophenonetetracarboxylic dianhydride and 2,2'"'"'-dichloro-4,4'"'"',5,5'"'"'-benzophenonetetracarboxylic dianhydride.

5. A polyamic acid of claim 4 wherein the tetracarboxylic dianhydride consists essentially of 3,3'"'"'4,4'"'"'-benzophenonetetracarboxylic dianhydride.

6. A polyimide derived from the polyamic acid of claim 1.

7. A polyimide derived from the polyamic acid of claim 2.

8. A polyimide derived from the polyamic acid of claim 3.

9. A polyimide derived from the polyamic acid of claim 4.

10. A polyimide derived from the polyamic acid of claim 5.

11. A process for inducing pre-tilt in alignment of a liquid crystal medium adjacent to a surface of an optical alignment layer comprising:

(a) exposing at least one optical alignment layer, comprising anisotropically absorbing molecules and hydrophobic moieties, to polarized light;

the polarized light having a wavelength within the absorption band of said anisotropically absorbing molecules;

wherein the exposed anisotropically absorbing molecules induce alignment of the liquid crystal medium at an angle + and -θ

with respect to the direction of the polarization of the incident light beam and along the surface of the optical alignment layer, and induce a pre-tilt at an angle Φ

with respect to the surface of the optical alignment layer; and

(b) applying a liquid crystal medium to the optical alignment layer, and wherein the anisotropically absorbing molecules and hydrophobic moieties are covalently bonded to a polyimide of claim 6.

12. A liquid crystal display element comprising a polyimide of claim 6.

13. A polyamic acid of claim 1 wherein the monoamine comprises about from 1 to 12 mol % of the amine component.