LIQUID CRYSTAL DISPLAY HAVING HIGH RESPONSE SPEED

• US 20120282838A1
• Filed: 06/26/2012
• Published: 11/08/2012
• Est. Priority Date: 09/17/2008
• Status: Active Grant

• Current Assignee: TCL China Star Optoelectronics Technology Co. Ltd. (TCL Technology Group Corp.)
• Original Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Inventors: KIM, Jae-Hoon
• Granted Patent: US 8,937,698 B2
• Time in Patent Office: Days
• US Class Current: 445/25
• CPC Class Codes: C09K 2323/02 Alignment layer characterised by chemical composition
• CPC Class Codes: C09K 2323/023 Organic silicon compound, e.g. organosilicon
• CPC Class Codes: C09K 2323/025 Polyamide
• CPC Class Codes: C09K 2323/027 Polyimide
• CPC Class Codes: G02F 1/133711 by organic films, e.g. polymeric films
• CPC Class Codes: G02F 1/133715 by first depositing a monomer
• CPC Class Codes: G02F 1/133726 made of a mesogenic material
• CPC Class Codes: G02F 1/133753 with different alignment orientations or pretilt angles on a same surface, e.g. for grey scale or improved viewing angle
• CPC Class Codes: G02F 1/133757 with different alignment orientations
• CPC Class Codes: G02F 1/133788 by light irradiation, e.g. linearly polarised light photo-polymerisation

Abstract

First alignment is performed by forming an alignment layer that includes a photopolymerizable monomer or oligomer on a substrate and the like, introducing liquid crystal, and bringing the liquid crystal into contact with the alignment layer including the photopolymerizable monomer or oligomer.

The liquid crystal is then subjected to secondary alignment by photopolymerizing the photopolymerizable monomer or oligomer including the alignment layer to form an alignment regulator in a state in which an electric field is applied to the liquid crystal to change the alignment of the liquid crystal.

Claims

1-174. -174. (canceled)

175. A method for manufacturing a liquid crystal display, comprising:

forming a first alignment layer that comprises an alignment base layer and a plurality of alignment regulators on a first substrate;

assembling the first substrate and a second substrate interposing liquid crystal layer therebetween; and

applying a voltage between a first electrode and a second electrode formed on at least one of the first substrate and the second substrate, and irradiating light to the first alignment layer so that the alignment regulators form pretilt states according to the electric field between the first electrode and the second electrode.

176. The method of claim 175, wherein the forming of the first alignment layer comprises:

coating a liquid film on the first substrate comprising the alignment base layer and the alignment regulators extended from the alignment base layer.

177. The method of claim 175, wherein the forming of the first alignment layer comprises:

coating a mixture comprising an alignment base material and a plurality of monomers or oligomers photopolymerizable by the irradiation of non-polarizing light on the first substrate.

178. The method of claim 177, wherein the forming of the first alignment layer comprises:

performing heat treatment of the mixture coated on the first substrate to cure the first alignment layer. the heat treatment is performed at a temperature in the range of 100 to 180.degree. C. for 0.5 to 1 hour.

179. The method of claim 178, further comprising, before the assembling of the first substrate and the second substrate, forming a second alignment layer that comprises an alignment base layer and a plurality of alignment regulators on the second substrate.

180. The method of claim 179, wherein the forming of the second alignment layer comprises:

coating a mixture comprising an alignment base material and the plurality of monomers or oligomers photopolymerizable by the irradiation of non-polarizing light on the second substrate.

181. The method of claim 180, wherein the forming of the second alignment layer comprises:

performing heat treatment of the mixture coated on the second substrate to cure the second alignment layer. the heat treatment is performed at a temperature in the range of 100 to 180.degree. C. for 0.5 to 1 hour.

182. The method of claim 178, wherein the assembling of the first substrate and the second substrate comprises:

coating a sealant on any one of the first substrate and the second substrate and dripping a liquid crystal; and

aligning the first substrate and the second substrate to perform attachment.

183. The method of claim 182, wherein the assembling of the first substrate and the second substrate comprises:

coating a sealant on either one of the first substrate and the second substrate so as to have a liquid crystal injection hole, and aligning the first substrate and the second substrate to perform attachment, and injecting the liquid crystal into a space formed by the first substrate, the second substrate, and the sealant.

184. The method of claim 183, wherein the plurality of alignment regulators are formed of reactive mesogens (RM).

185. The method of claim 184, wherein the reactive mesogen is represented by the following formula:

P1-A1-(Z1-A2)n-P2, wherein P1 and P2 are independently selected from acrylate, methacrylate, vinyl, vinyloxy, and epoxy groups, A1 and A2 are independently selected from 1,4-phenylene and naphthalene-2,6-diyl groups, Z1 is any one of COO—

, OCO—

, and single bonds, and n is any one of 0, 1, and 2.

186. The method of claim 185, wherein the reactive mesogen is represented by any one of the following formulas:

##STR00002## wherein P1 and P2 are independently selected from acrylate, methacrylate, vinyl, vinyloxy, and epoxy groups.

187. The method of claim 184, wherein the alignment base layer comprises at least one of a poly-amic acid, a poly-imide, lecithin, nylon, and PVA (polyvinyl alcohol).

188. The method of claim 177, further comprising injecting a liquid crystal material between the first substrate and the second substrate after polymerizing the monomers or oligomers included in the first alignment layer.

189. The method of claim 177, further comprising, before the assembling of the first substrate and the second substrate, forming a second alignment layer including an alignment base layer and a plurality of monomers or oligomers on a second substrate, wherein the plurality of monomers or oligomers included in the second alignment layer are polymerized when the plurality of monomers or oligomers included in the first alignment layer are polymerized.

190. The method of claim 189, wherein the first alignment layer further includes a polymerization initiator.

191. The method of claim 190, wherein the second alignment layer includes a polymerization initiator.

192. The method of claim 191, wherein the polymerization initiator may include at least one of methyl ethyl kotone peroxide, benzoyl peroxide, cumene hydroperoxide, t-butyl peroctoate, dicumyl peroxide, or benzoyl alkyl ether based compounds, acetophenone based compounds, benzophenone based compounds, xanthone based compounds, benzoin ether based compounds, and benzyl ketal based compounds.

193. The method of claim 175, wherein the first electrode is formed on the first substrate, the second electrode is formed on the second substrate, and the first electrode comprises a first cutout.

194. The method of claim 193, wherein the second electrode comprises the second cutout.

195. The method of claim 193, further comprising forming an organic material protrusion on the second electrode.

196. The method of claim 195, further comprising forming an organic material protrusion on at least one of the first electrode and the second electrode.

197. A method for manufacturing a liquid crystal display, comprising:

forming a first electrode throughout a first region and a second region on the first substrate;

forming a second electrode on a second substrate;

forming a first alignment layer that comprises a first alignment base layer and first alignment regulators on one of the first substrate and the second substrate;

introducing a liquid crystal between the first substrate and the second substrate;

covering the second region by a photomask;

applying a first voltage between the first electrode and the second electrode, and irradiating a light to the first alignment layer to form a pre-tilt in the first region; and

applying a second voltage between the first electrode and the second electrode, and irradiating a light to the first alignment layer to form a pretilt in the second region, wherein the first voltage and the second voltage are different from each other.

198. The method of claim 197, further comprising forming a first domain division means in the first electrode.

199. The method of claim 198, wherein the first domain division means is a cutout formed together in the patterning of the first electrode.

200. The method of claim 199, further comprising forming a second domain division means in the second electrode.

201. The method of claim 200, wherein the second domain division means is a cutout formed together in the patterning of the second electrode.

202. The method of claim 201, further comprising, before the introducing of the liquid crystal between the first substrate and the second substrate, forming a second alignment layer that comprises an second alignment base layer and a plurality of second alignment regulators on one of the first substrate and the second substrate;

203. The method of claim 202, further comprising:

forming a gate line on the first substrate; and

forming a data line insulated from and crossing the gate line, a drain electrode extended from the data line, and a capacitive coupling electrode connected to the drain electrode, wherein the first electrode includes the first subpixel electrode connected to the drain electrode, and the second subpixel electrode separated from the first subpixel electrode and overlapping the capacitive coupling electrode.

204. The method of claim 203, further comprising:

forming a gate line on the first substrate;

forming a data line insulated from and crossing the gate line; and

forming a thin film transistor connected to the gate line and the data line, and having a drain electrode, wherein the first electrode is connected to the thin film transistor through the drain electrode, and wherein the first electrode includes first and second pixel electrodes, the gate line includes a first gate line and a second gate line respectively disposed for the first and second pixel electrodes, the thin film transistor includes first and second thin film transistors respectively connected to the first and second pixel electrodes, the first and second gate lines, and the data line, and the drain electrode includes first and second drain electrodes.

205. A method for manufacturing a liquid crystal display, comprising:

forming a first electrode on a first substrate;

forming a second electrode on a second substrate facing the first substrate;

forming a first alignment layer that comprises an alignment base layer and photopolymerizable monomers or oligomers on one of the first and second substrates;

forming a liquid crystal layer including photopolymerizable monomers or oligomers and a liquid crystal between the first substrate and the second substrate; and

applying a voltage between the first electrode and the second electrode, and irradiating light to the first alignment layer to polymerize the photopolymerizable monomers or oligomers to form alignment regulators having a pretilt of a predetermined angle in the first alignment layer.

206. The method of claim 205, further comprising forming a domain division means dividing the first electrode into a plurality of domains on the first substrate.

207. The method of claim 206, wherein the forming of the domain division means includes forming a cutout in the first electrode, or a protrusion on the first electrode.

208. The method of claim 207, wherein azimuthal angles of the pretilt of the alignment regulators formed in the domains are different from each other between neighboring domains.

209. A method for manufacturing a liquid crystal display, comprising:

forming a first alignment layer that comprises an alignment base layer and a photopolymerizable monomer or oligomer, and a polymerization initiator on a first substrate;

assembling the first substrate on which the first alignment layer is formed and a second substrate;

applying a voltage between a first electrode and a second electrode formed on at least one of the first substrate and the second substrate, and polymerizing the monomer or oligomer included in the first alignment layer; and

injecting a liquid crystal material between the first substrate and the second substrate after polymerizing the monomer or oligomer included in the first alignment layer.

210. A method for manufacturing a liquid crystal display, comprising:

providing a first substrate including a gate line, a data line intersecting the gate line, a thin film transistor having a control electrode and an input electrode respectively connected to the gate line and the data line, a first linear electrode connected to an output terminal of the thin film transistor, and a second linear electrode facing the first linear electrode;

providing a second substrate;

forming a first alignment layer that comprises a alignment base layer and a photopolymerizable monomer or oligomer, and a polymerization initiator on one of the first substrate and the second substrate;

assembling the first substrate on which the first alignment layer is formed and a second substrate; and

applying a voltage between the first linear electrode and the second linear electrode, and irradiating light to the first alignment layer to polymerize the photopolymerizable monomer or oligomer.

211. A method for manufacturing a liquid crystal display, comprising:

forming a first alignment layer that comprises an alignment base layer and a plurality of photo-reactive functional groups assembling the first substrate on which the first alignment layer is formed and a second substrate;

applying a voltage between a first electrode and a second electrode formed on at least one of the first substrate and the second substrate, and injecting a liquid crystal material between the first substrate and the second substrate wherein the photo-reactive functional group is the reactive mesogen represented by the following formula;

P1-A1-(Z1-A2)n-P2, wherein P1 and P2 are independently selected from acrylate, methacrylate, vinyl, vinyloxy, and epoxy groups, A1 and A2 are independently selected from 1,4-phenylene and naphthalene-2,6-diyl groups, Z1 is any one of COO—

, OCO—

, and single bonds, and n is any one of 0, 1, and 2.