Liquid crystal device, process for producing same and liquid crystal apparatus

Abstract

A liquid crystal device, comprising: a pair of substrates each provided with an electrode including one substrate having thereon a color filter and a coating layer, and a liquid crystal layer comprising a chiral smectic liquid crystal disposed together with spacer beads between the pair of substrates, wherein the liquid crystal layer has a thickness smaller than a diameter of the spacer beads and a maximum thickness of the coating layer, the coating layer having a pencil hardness of at most 7H. The above layer structure between the substrates is effective in improving resistance to external shock and providing a uniform cell gap.

What is claimed is:  
     
         1 . A liquid crystal device, comprising: a pair of substrates each provided with an electrode including one substrate having thereon a color filter and a coating layer, and a liquid crystal layer comprising a chiral smectic liquid crystal disposed together with spacer beads between the pair of substrates, wherein 
 the liquid crystal layer has a thickness smaller than a diameter of the spacer beads and a maximum thickness of the coating layer, the coating layer having a pencil hardness of at most 7H.    
     
     
         2 . A device according to    claim 1   , comprising a sealing agent disposed between the pair of substrates at a peripheral portion thereof, the coating layer extending to a portion corresponding to the peripheral portion.  
     
     
         3 . A device according to    claim 1   , wherein the coating layer has a pencil hardness of 3H-7H.  
     
     
         4 . A process for producing a liquid crystal device, comprising the steps of: 
 forming on a first insulating substrate a light-interrupting layer, a color filter comprising plural color filter segments, a coating layer, a barrier layer, a transparent electrode, an auxiliary electrode, a short-circuit prevention layer, a roughened surface-forming layer, and an insulating layer in succession in this order,    forming on a second insulating substrate a transparent electrode, an auxiliary electrode, a short-circuit prevention layer, a roughened surface-forming layer, and an insulating layer in succession in this order,    rubbing the surface of each of the alignment layers on the first and second substrates, dispersing adhesive beads over the alignment layer surface formed on the first substrate or the second substrate,    disposing a sealing agent having a prescribed pattern on the insulating layer surface formed on the second substrate or the first substrate,    dispersing spacer beads over the insulating layer surface provided with the sealing agent,    adhesively bonding the first and second substrate to each other while fixing the first or second substrate over which the adhesive beads are dispersed,    scribing the first and second substrates to remove an unnecessary portion,    injecting a chiral smectic liquid crystal from an injection port into a gap between the first and second substrates, and    sealing up the injection port.    
     
     
         5 . A process according to    claim 4   , wherein each of the first and second insulating substrates comprises a glass plate immediately on which an undercoat layer comprising SiO 2  is formed in a thickness of 200-1000 Å.  
     
     
         6 . A process according to    claim 4   , wherein the light-interrupting layer comprises a black stripe composed of an alloy of Mo and Ta having a thickness of 500-1500 Å.  
     
     
         7 . A process according to    claim 4    wherein the color filter comprises a resin layer having a thickness of 1.0-2.0 μm and comprising plural photosensitive resins containing at least one pigment.  
     
     
         8 . A process according to    claim 7   , wherein the photosensitive resins comprise polyamide.  
     
     
         9 . A process according to    claim 4   , wherein the coating layer comprises an organic silane-based resin layer having a maximum thickness of 1.5-5 μm.  
     
     
         10 . A process according to    claim 4   , wherein the barrier layer comprises an SiO 2  layer having a thickness of 100-1000 Å.  
     
     
         11 . A process according to    claim 4   , wherein each of the transparent electrodes formed on the first and second substrates comprises an ITO layer having a thickness of 300-3000 Å.  
     
     
         12 . A process according to    claim 4   , wherein each of the auxiliary electrodes formed on the first and second substrates comprises a metal lamination layer of Mo—Ta/Al/Mo—Ta having a thickness of 500-2500 Å.  
     
     
         13 . A process according to    claim 4   , wherein each of the short-circuit prevention layers formed on the first and second substrates comprises a lamination layer including a Ta 2 O 5  layer having a thickness of 500-1200 Å and a Ti—Si layer disposed thereon having a thickness of 500-1000 Å.  
     
     
         14 . A process according to    claim 4   , wherein each of the roughened surface-forming layers formed on the first and second substrates comprises a Ti—Si layer having a thickness of 100-300 Å and containing SiO 2  beads dispersed therein having a diameter of 300-700 Å.  
     
     
         15 . A process according to    claim 4   , wherein each of the insulating layer comprises a polyimide film having a thickness of 50-1000 Å.  
     
     
         16 . A process according to    claim 4   , wherein the rubbing step is performed by rubbing the surface of the insulating layer with a rubbing roller about which a raised rubbing cloth comprising aramide fiber is wound.  
     
     
         17 . A process according to    claim 4   , wherein the dispersion of the adhesive beads on one substrate is performed by dispersing a dispersion of adhesive beads comprising a thermosetting resin having a diameter of 2-10 μm in a solvent at a density of 50-130 particles/mm 2  in a region corresponding to a sealing area within a sealing portion of the other substrate.  
     
     
         18 . A process according to    claim 17   , wherein the thermosetting resin comprises epoxy resin or acrylic resin.  
     
     
         19 . A process according to    claim 4   , wherein the sealing agent comprises a thermosetting resin.  
     
     
         20 . A process according to    claim 19   , wherein the thermosetting resin comprises epoxy resin.  
     
     
         21 . A process according to    claim 4   , wherein the dispersion step of the spacer beads is performed by dispersing the spacer beads in the form of a dispersion in ethanol so as to provide a density of 100-700 particles/mm 2 .  
     
     
         22 . A process according to    claim 21   , wherein the spacer beads comprise silica beads having a diameter of 0.6-3.5 μm.  
     
     
         23 . A process according to    claim 4   , wherein the adhesive beads and the spacer beads are dispersed on the first substrate and the second substrate, respectively.  
     
     
         24 . A process according to    claim 4   , wherein the resultant liquid crystal device has a cell gap of 0.5-3 μm.  
     
     
         25 . A process according to    claim 4   , wherein, in the scribing step, the first and second substrates have different scribing positions.  
     
     
         26 . A process according to    claim 4   , wherein, the sealing step of the injection port is performed by using a room temperature curing epoxy resin.  
     
     
         27 . A liquid crystal device, comprising: a pair of oppositely disposed substrates each provided with a group of transparent electrodes in the form of stripes, and a liquid crystal disposed between the substrates, wherein 
 each of the transparent electrodes partially has an auxiliary electrode in its length direction and has both lead-out end portions in a region other than a display region, each of the lead-out end portions including an exposed check portion where the auxiliary electrode is patternized so as to expose the transparent electrode.    
     
     
         28 . A device according to    claim 27   , wherein the exposed check portions has a width larger than that of the remaining portion and are disposed alternately at every transparent electrode in their width direction.  
     
     
         29 . A device according to    claim 27   , wherein each of the exposed check portion has both end portions where the auxiliary electrode is connected so as to enclose the exposed check portion.  
     
     
         30 . A device according to    claim 27   , wherein the device includes a dummy electrode in a region other than a display region.  
     
     
         31 . A device according to    claim 27   , wherein the pair of substrates includes one substrate having thereon a color filter and a coating layer, and includes a liquid crystal layer comprising a chiral smectic liquid crystal as the liquid crystal disposed together with spacer beads between the pair of substrates, wherein 
 the liquid crystal layer has a thickness smaller than a diameter of the spacer beads and a maximum thickness of the coating layer, the coating layer having a pencil hardness of at most 7H.    
     
     
         32 . A device according to    claim 31   , comprising a sealing agent disposed between the pair of substrates at a peripheral portion thereof, the coating layer extending to a portion corresponding to the peripheral portion.  
     
     
         33 . A device according to    claim 31   , wherein the coating layer has a pencil hardness of 3H-7H.  
     
     
         34 . A color liquid crystal display apparatus, including: 
 a liquid crystal device, comprising: a pair of oppositely disposed first and second substrates each provided with a group of transparent electrodes in the form of stripes, and a liquid crystal layer comprising a chiral smectic liquid crystal disposed together with spacer beads between the pair of substrates, the first substrate having thereon a color filter comprising plural color filter segments and a coating layer, wherein the transparent electrodes on the second substrate have a width smaller than that of the transparent electrodes on the first substrate,    scanning signal supply means for supplying scanning signals to the transparent electrodes on the first substrate, and    data signal supply means for supplying data signals including an interval at a prescribed temperature or below to the transparent electrodes on the second substrate, each of the data signals corresponding to each of color filter segments of the color filter.    
     
     
         35 . An apparatus according to    claim 34   , wherein the liquid crystal layer has a thickness smaller than a diameter of the spacer beads and a maximum thickness of the coating layer, and the coating layer has a pencil hardness of at most 7H.  
     
     
         36 . An apparatus according to    claim 34   , wherein the liquid crystal device comprises a sealing agent disposed between the first and second substrates at a peripheral portion thereof, and the coating layer extends to a portion corresponding to the peripheral portion.  
     
     
         37 . An apparatus according to    claim 34   , wherein the coating layer has a pencil hardness of 3H-7H.  
     
     
         38 . A liquid crystal device, comprising: a pair of oppositely disposed substrates each provided with a group of transparent electrodes, and a liquid crystal disposed between the substrates, the groups of transparent electrodes of the pair of substrates intersect with each other to form a pixel at each intersection, wherein 
 one of the substrates includes a light-interrupting layer for covering a part of the pixel located in a position corresponding to at least one end portion of the pixel.    
     
     
         39 . A device according to    claim 38   , wherein the liquid crystal comprises a chiral smectic liquid crystal.  
     
     
         40 . A device according to    claim 38   , wherein the pair of substrates includes at least one substrate which has been subjected to uniaxial aligning treatment from a prescribed starting position in a uniaxial aligning direction forming an angle of 50-90° C. with respect to the light-interrupting layer, and the end portion of the pixel has an edge line closer to the prescribed starting position.  
     
     
         41 . A device according to    claim 39   , wherein the chiral smectic liquid crystal has a small thickness sufficient to suppress formation of a helical structure thereof, and shows a tendency to generate a hairpin defect and a lightning defect in pairs.  
     
     
         42 . A device according to    claim 41   , wherein the lightning defect is located a position closer to the light-interrupting layer than the hairpin defect when the hairpin defect and the lightning defect in pairs are generated.  
     
     
         43 . A device according to    claim 41   , wherein chiral smectic liquid crystal assumes C 1  uniform alignment state.  
     
     
         44 . A device according to    claim 38   , wherein the light-interrupting layer has a width larger than that of another light-interrupting layer located in a position corresponding to another end portion of the pixel.  
     
     
         45 . A device according to    claim 38   , wherein at least one of the pair of substrates has a color filter comprising plural color filter segments in the form of stripes or dots under or below a corresponding group of transparent electrodes, each of the pixels comprising at least one color filter segment.