Liquid crystal display device and method of fabricating the same
An LCD device includes first and second substrates, an alignment layer formed on at least one of the substrates, and a liquid crystal layer formed between the substrates, wherein the alignment layer is formed of a polymeric material containing a polymer main chain and a photo-reaction group combined with the polymer main chain that generates a photo-dimerization reaction by UV rays.
1 . An LCD device comprising:
first and second substrates;
an alignment layer formed on at least one of the substrates; and
a liquid crystal layer formed between the substrates,
wherein the alignment layer is formed of a polymeric material containing a polymer main chain and a photo-reaction group combined with the polymer main chain that generates a photo-dimerization reaction by UV rays.
2 . The LCD device as claimed in claim 1 , wherein the photo-reaction group is selected from a group of a Cinnamoyl based material, a Chalcone based material, a Coumarine based material, and a Maleimide based material.
3 . The LCD device as claimed in claim 2 , wherein the photo-reaction group is a Cinnamoyl compound expressed by the following chemical formula:
wherein X is selected from a group of —((CH 2 )nO)m-, —O((CH 2 )nO)m-,
(m and n are positive numbers between 0 and 10), and Y is selected from a group of
in the above Y, each of 1 to 9 is selected from a group of -A, —(CA 2 )nCA 3 , —O(CA 2 )nCA 3 , —(O(CA 2 )m)nCA 3 , —O(CA 2 )nOCA 3 , —(OCA 2 )m)nOCA 2 ,
(m and n are positive numbers between 0 and 10, and A and B respectively represent H, F, Cl, CN, CF 3 or CH 3 ).
4 . The LCD device as claimed in claim 2 , wherein the photo-reaction group is a Chalcone compound expressed by the following chemical formula:
wherein n is a positive number between 0 and 10, each of 1 to 5 is selected from a group of -A, —(CA 2 )nCA 3 , —O(CA 2 )nCA 3 , —(O(CA 2 )m)nCA 3 , —O(CA 2 )nOCA 3 , —(O(CA 2 )m)nOCA 3 ,
(m and n are positive numbers between 0 and 10, and A and B respectively represent H, F, Cl, CN, CF 3 or CH 3 ).
5 . The LCD device as claimed in claim 2 , wherein the photo-reaction group is a Coumarine compound expressed by the following chemical formula:
wherein each of 1 to 6 is selected from a group of -A, —(CA 2 )nCA 3 , —O(CA 2 )nCA 3 , —(O(CA 2 )m)nCA 3 , —O(CA 2 )nOCA 3 , —
(O(CA 2 )m)nOCA 3 ,
(m and n are positive numbers between 0 and 10, and A and B respectively represent H, F, Cl, CN, CF 3 or CH 3 ).
6 . The LCD device as claimed in claim 2 , wherein the photo-reaction group is a Maleimide compound expressed by the following chemical formula:
wherein Y is selected from a group of
(n is a positive number between 0 and 10), and each of 1 and 2 is selected from a group of —H, —F, —CH 3 , —CF 3 , —CN,
7 . The LCD device as claimed in claim 1 , wherein the polymer main chain is a polymeric material selected from a group of polyimide, polyamic acid, polyamide, polynorbornene, polyamideimide, polyvinyl, polyolefine, polystyrene, polyacrylate, poly(vinylchloride), polyether, polyester, polythioether, polysulfone, polyethersulfone, polyetheretherketon, polyurea, polyurethane, polybenzimidazol, polyacetal, and poly(vinylacetate).
8 . The LCD device as claimed in claim 7 , wherein the polymer main chain is a polyimide compound or a polyamicacid compound expressed by the following chemical formula:
wherein m+n=1, 0≦m≦1 and 0≦n≦1 are obtained.
9 . The LCD device as claimed in claim 8 , wherein the polyimide compound or the polyamicacid compound is fabricated by a reaction between amine and dianhydride.
10 . The LCD device as claimed in claim 9 , wherein the dianhydride is selected from a group of
11 . The LCD device as claimed in claim 10 , wherein a hydrogen atom of the dianhydride is replaced with a Cinnamoyl compound.
12 . The LCD device as claimed in claim 10 , wherein a hydrogen atom of the dianhydride is replaced with a Chalcone compound.
13 . The LCD device as claimed in claim 10 , wherein a hydrogen atom of the dianhydride is replaced with a Coumarine compound.
14 . The LCD device as claimed in claim 10 , wherein a hydrogen atom of the dianhydride is replaced with a Maleimide compound.
15 . The LCD device as claimed in claim 9 , wherein the amine is selected from a group of (a) to (e):
(a)
wherein, X1 is O, CO,
(n is a positive number between 0 and 20, and H may be replaced with F),
(n is a positive number between 0 and 20, and H may be replaced with F),
and X1 is an ortho-, meta-, para-, or their composite structure,
wherein R1 and R2 are (CH 2 )n (n is a positive number between 0 and 10) or
wherein X is (CH 2 )nH, CN, OCF 3 , O(CH 2 )nH, or O(CF 2 )nCF 3 , and X is an ortho-, meta-, para-, or their composite structure,
(d)
NH 2 —(CH 2 )n-NH 2 ,
wherein n is a positive number between 1 and 20, and
wherein m and n are positive numbers between 0 and 10.
16 . The LCD device as claimed in claim 15 , wherein a hydrogen atom of the amine is replaced with a Cinnamoyl compound.
17 . The LCD device as claimed in claim 15 , wherein a hydrogen atom of the amine is replaced with a Chalcone compound.
18 . The LCD device as claimed in claim 15 , wherein a hydrogen atom of the amine is replaced with a Coumarine compound.
19 . The LCD device as claimed in claim 15 , wherein a hydrogen atom of the amine is replaced with a Maleimide compound.
20 . The LCD device as claimed in claim 1 , wherein the polymeric material of the alignment layer has λmax in the range of about 270 nm to 350 nm.
21 . The LCD device as claimed in claim 1 , wherein the polymeric material includes a benzene ring is an ortho-, meta-, para- or their composite structure.
22 . A method of fabricating an LCD device having first and second substrates, comprising:
coating an alignment layer on at least one of the substrates;
rubbing the alignment layer; and
irradiating polarized UV rays onto the alignment layer,
wherein the alignment layer is formed of a polymeric material containing a polymer main chain and a photo-reaction group combined with the polymer main chain that generates a photo-dimerization reaction by UV rays.
23 . The method as claimed in claim 22 , wherein an alignment direction of the alignment layer rubbed is identical with an alignment direction of the alignment layer irradiated with UV rays.
24 . The method as claimed in claim 22 , wherein the step of irradiating the UV rays is performed on the entire surface of the substrate.
25 . The method as claimed in claim 22 , wherein the step of irradiating the UV rays is performed only in a region of the alignment layer where step is formed on the substrate.
26 . The method as claimed in claim 22 , wherein the rubbing process is performed before the step of irradiating the UV rays.
27 . The method as claimed in claim 22 , wherein the step of irradiating the UV rays is performed before the rubbing process.
28 . The method as claimed in claim 22 , wherein the rubbing process and the step of irradiating the UV rays are performed simultaneously.
29 . The method as claimed in claim 22 , wherein the step of irradiating the UV rays is performed by irradiating partially polarized UV rays or linearly polarized UV rays.
30 . The method as claimed in claim 22 , wherein the polarized UV rays have an irradiation energy in the range of 10 mJ to 3000 mJ.
31 . The method as claimed in claim 22 , wherein the UV rays are irradiated vertically or obliquely to the substrate.
32 . The method as claimed in claim 22 , wherein the step of coating the alignment layer is performed by spin coating or roll coating after dissolving an alignment component in an organic solvent at the concentration of 1˜20 wt % and viscosity of 1˜10000 cps.
33 . The method as claimed in claim 22 , wherein the step of coating the alignment layer is performed to obtain a thickness of 50 nm to 200 nm.
34 . The method as claimed in claim 22 , further comprising bonding both substrates to each other.
35 . The method as claimed in claim 34 , wherein the step of bonding both substrates to each other includes dropping a liquid crystal onto any one of the substrates.
36 . The method as claimed in claim 22 , wherein the photo-reaction group is selected from a group of a Cinnamoyl based material, a Chalcone based material, a Coumarine based material, and a Maleimide based material.
37 . The method as claimed in claim 36 , wherein the photo-reaction group is a Cinnamoyl compound expressed by the following chemical formula:
wherein X is selected from a group of —((CH 2 )nO)m-, —O((CH 2 )nO)m-,
(m and n are positive numbers between 0 and 10), and Y is selected from a group of
in the above Y, each of 1 to 9 is selected from a group of -A, —(CA 2 )nCA 3 , —O(CA 2 )nCA 3 , —(O(CA 2 )m)nCA 3 , —O(CA 2 )nOCA 3 , —(O(CA 2 )m)nOCA 3 ,
(m and n are positive numbers between 0 and 10, and A and B respectively represent H, F, Cl, CN, CF 3 or CH 3 ).
38 . The method as claimed in claim 36 , wherein the photo-reaction group is a Chalcone compound expressed by the following chemical formula:
wherein n is a positive number between 0 and 10, each of 1 to 5 is selected from a group of -A, —(CA 2 )nCA 3 , —O(CA 2 )nCA 3 , —(O(CA 2 )m)nCA 3 , —O(CA 2 )nOCA 3 , —(O(CA 2 )m)nOCA 3 ,
(m and n are positive numbers between 0 and 10, and A and B respectively represent H, F, Cl, CN, CF 3 or CH 3 ).
39 . The method as claimed in claim 36 , wherein the photo-reaction group is a Coumarine compound expressed by the following chemical formula:
wherein each of 1 to 6 is selected from a group of -A, —(CA 2 )nCA 3 , —O(CA 2 )nCA 3 , —(O(CA 2 )m)nCA 3 , —O(CA 2 )nOCA 3 , —(O(CA 2 )m)nOCA 3 ,
(m and n are positive numbers between 0 and 10, and A and B respectively represent H, F, Cl, CN, CF 3 or CH 3 ).
40 . The method as claimed in claim 36 , wherein the photo-reaction group is a Maleimide compound expressed by the following chemical formula:
wherein Y is selected from a group of
(n is a positive number between 0 and 10), and each of 1 and 2 is selected from a group of —H, —F, —CH 3 , —CF 3 , —CN,
41 . The method as claimed in claim 22 , wherein the polymer main chain is a polymeric material selected from a group of polyimide, polyamic acid, polyamide, polynorbornene, polyamideimide, polyvinyl, polyolefine, polystyrene, polyacrylate, poly(vinylchloride), polyether, polyester, polythioether, polysulfone, polyethersulfone, polyetheretherketon, polyurea, polyurethane, polybenzimidazol, polyacetal, and poly(vinylacetate).
42 . The method as claimed in claim 41 , wherein the polymer main chain is a polyimide compound or a polyamicacid compound expressed by the following chemical formula:
wherein m+n=1, 0≦m≦1, and 0≦n≦1 are obtained.
43 . The method as claimed in claim 42 , wherein the polyimide compound or the polyamicacid compound is fabricated by a reaction between amine and dianhydride.
44 . The LCD device as claimed in claim 43 , wherein the dianhydride is selected from a group of
45 . The method as claimed in claim 44 , wherein a hydrogen atom of the dianhydride is replaced with the Cinnamoyl compound.
46 . The method as claimed in claim 44 , wherein a hydrogen atom of the dianhydride is replaced with the Chalcone compound.
47 . The method as claimed in claim 44 , wherein a hydrogen atom of the dianhydride is replaced with the Coumarine compound.
48 . The method as claimed in claim 44 , wherein a hydrogen atom of the dianhydride is replaced with the Maleimide compound.
49 . The method as claimed in claim 43 , wherein the amine is selected from a group of (a) to (e):
wherein, X1 is O, CO,
(n is a positive number between 0 and 20, and H may be replaced with F),
(n is a positive number between 0 and 20, and H may be replaced with F),
and X1 is an ortho-, meta-, para-, or their composite structure,
wherein R1 and R2 are (CH 2 )n (n is a positive number between 0 and 10) or
wherein X is (CH 2 )nH, CN, OCF 3 , O(CH 2 )nH, or O(CF 2 )nCF 3 , and X is an ortho-, meta-, para-, or their composite structure,
(d)
NH 2 —(CH 2 )n-NH 2 ,
wherein n is a positive number between 1 and 20, and
wherein m and n are positive numbers between 0 and 10.
50 . The method as claimed in claim 49 , wherein a hydrogen atom of the amine is replaced with the Cinnamoyl compound.
51 . The method as claimed in claim 49 , wherein a hydrogen atom of the amine is replaced with the Chalcone compound.
52 . The method as claimed in claim 49 , wherein a hydrogen atom of the amine is replaced with the Coumarine compound.
53 . The method as claimed in claim 49 , wherein a hydrogen atom of the amine is replaced with the Maleimide compound.
54 . The method as claimed in claim 22 , wherein the polymeric material of the alignment layer has λmax in the range of about 270 nm to 350 nm so as not to generate photo-decomposition due to UV rays.
55 . The method as claimed in claim 22 , wherein the polymeric material including a benzene ring is an ortho-, meta-, para- or their composite structure.