JP2005099266A - Phase difference control substrate and display - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a phase difference control substrate wherein thickening of film thickness due to an ink returning phenomenon is eliminated when a phase difference controlling layer is provided, then, uniform cell gap can be obtained over the entire region of a display area when a liquid crystal cell is constituted, cutting especially collective bonding of a plurality of screens after bonding to a counter substrate is made possible and dust generated when cutting neither contaminates nor damages the display area. <P>SOLUTION: The phase difference control layer 4 composed of a liquid crystalline polymer is layered on a substrate 2 via a color filter layer 3 etc. and the phase difference control layer 4 is layered so as to leave a margin at an outer peripheral part of the substrate (1) or so as to be flat from the center part to the outer peripheral part of the phase difference control layer 4 (2). In the case (2), the thickness of the outer peripheral part is preferably made to be ≤+10 μm as compared with the flat part of the center part of the layer 4. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an improved retardation control substrate in which the thickness of the retardation control layer in the outer peripheral portion of the substrate is eliminated from that of other portions, and the retardation control substrate is The present invention relates to a display configured by using, in particular, a liquid crystal display.

  In various types of displays, retardation films are often used on the viewing side for the purpose of adjusting the viewing angle. For example, in a reflection type liquid crystal display, in order to obtain circularly polarized light, a quarter-wave retardation film is used in addition to a linearly polarizing plate. Further, in a vertical alignment mode liquid crystal display widely applied to a liquid crystal display for TV in recent years, a phase difference having a negative birefringence anisotropy in which the optical axis is perpendicular to the substrate in order to reduce the viewing angle dependency. Both a film (negative C plate) and a retardation film (positive A plate) whose optical axis is horizontal to the substrate and has positive birefringence anisotropy are used. Many retardation films such as viewing angle compensation films using liquid crystals are on the market.

  These retardation films are used by sticking other retardation plates and polarizing plates to each other with their optical axes at a specific angle and sticking them outside the liquid crystal cell. Since the refractive index of the film differs from the refractive index of the retardation film or polarizing plate, external light is reflected at the bonding interface, and this external light reflection lowers the display contrast and remarkably deteriorates the image quality.

  Such a problem can be solved by applying a retardation control layer made of a liquid crystalline polymer in the liquid crystal cell instead of applying the retardation film described above outside the liquid crystal cell. That is, a liquid crystal having a glass transition temperature and using a liquid crystalline polymer that can freeze the liquid crystal structure below the glass transition temperature, or having a reactive group such as an unsaturated bond in the molecular structure A phase difference control layer can be formed by applying a reactive monomer and three-dimensionally crosslinking in the liquid crystal layer state using the reactive group to freeze the liquid crystal structure.

  By the way, when constituting the retardation control layer, the above liquid crystalline polymer or liquid crystalline monomer is formed on a substrate having an alignment function by using a known method such as a spin coating method, a slit & spin coating method, or the like. It can be applied uniformly. However, in coating by these known methods, the film thickness uniformity of the coating film is excellent except for the outer peripheral portion of the substrate to be coated. However, the film returns to the outer peripheral portion from the end surface of the substrate due to a so-called ink return phenomenon. There is a problem that the thickness increases. For example, as shown in FIG. 4A, in the conventional phase difference control plate 11, a color filter (indicated by “CF” in the figure) layer 13 is laminated on a substrate 12, and the color filter layer 13 is covered. The phase difference control layer 14 is laminated so as to cover the outer peripheral portion of the substrate 12 of the phase difference control layer 14 and has a raised portion 14a having a thick film thickness.

  Among the displays, particularly in a liquid crystal display, it is desirable to use a retardation control substrate in which a retardation control layer is laminated on the entire surface of one of the substrates sandwiching the liquid crystal layer. When overlapping the counter substrate with the phase difference control layer on the inside, it is necessary to obtain a uniform cell gap over the entire display area. This is because if the cell gap is uneven, display unevenness occurs, and the display quality is significantly impaired. However, as shown in FIG. 4B, the phase difference control plate having the raised portion 14 a of the phase difference control layer 14 whose thickness is increased due to the ink return phenomenon at the outer peripheral portion of the substrate 12 as described above. When 11 is used, the cell gap in the outer peripheral portion of the liquid crystal cell 15 becomes large due to the influence of the raised portion 14a, so that it is difficult to obtain a uniform cell gap over the entire display area. In particular, in the case of multi-sided arrangement in which the color filter layer 13 is provided on the substrate 12 for a plurality of screens, a plurality of liquid crystal display cells are formed at the same time on the counter substrate. It is difficult to obtain a uniform cell gap in the plane.

  In order to obtain a uniform cell gap, it may be possible to cut and remove the thickened ink film on the outer periphery in advance, but then add the cutting process. The risk of polluting and scratching the display area with dust is unavoidable, and it is also possible to eliminate contamination and scratches by providing a cutting protective film, but the cutting protective film forming process and removal process have also been added, An increase in the number of processes is inevitable. In addition, when cutting is performed, the screens are inevitably overlapped on a screen-by-screen basis, resulting in poor manufacturing efficiency.

Alternatively, a retardation plate is also introduced in which a liquid crystal layer composed of a low-molecular nematic liquid crystal and a non-liquid crystalline polymer substance is sandwiched between two transparent substrates. (For example, refer to Patent Document 1).
JP-A-8-286179 (page 3, FIG. 1).

  However, with the retardation plate described in Patent Document 1, the disadvantage of using two transparent substrates is inevitable even if the thickness of the retardation control layer can be made uniform, and the retardation control layer is included in the liquid crystal cell. There is no intention to set up.

  In view of the above problems, the present invention eliminates the point that the film thickness has increased due to the ink return phenomenon from the end surface of the substrate to the outer periphery, and covers the entire display area when used in the construction of a liquid crystal cell. A uniform cell gap can be obtained, so that the cutting process after bonding to the counter substrate is possible, and in particular, batch bonding for multiple screens is possible. It is an object of the present invention to provide a phase difference control plate that does not cause a risk of polluting the display area or causing scratches.

  As a result of the inventor's investigation, the solution to the point that the film thickness of the retardation control layer has increased due to the ink return phenomenon from the end surface of the substrate to the outer peripheral part is to remove the outer peripheral retardation control layer or It became clear that the problem can be solved by processing the thinned part of the retardation control layer of the part to make it thin, taking either means, or taking both means simultaneously. The present invention has been reached.

  A first invention for solving the problem has a laminated structure in which at least one retardation control layer made of a liquid crystalline polymer is laminated on a substrate, and the retardation controlling layer comprises (1) the substrate. Or (2) flat from the center portion to the outer peripheral portion of the retardation control layer, or the above (1) and (2) The present invention relates to a phase difference control board characterized by being both.

  According to a second invention, in the first invention, the retardation control layer is flat from the central portion to the outer peripheral portion, and the thickness of the outer peripheral portion of the retardation control layer is larger than the thickness of the central portion. The present invention relates to a phase difference control board characterized by being +10 μm or less.

  A third invention relates to the phase difference control substrate according to the first or second invention, wherein a color filter layer is laminated in addition to the phase difference control layer.

  According to a fourth aspect of the present invention, an overcoat layer is laminated on a surface opposite to the substrate side of the phase difference control layer of the phase difference control substrate of any one of the first to third aspects, and the overcoat layer Is (a) laminated with a margin left on the outer periphery of the substrate, or (b) flat from the center to the outer periphery of the overcoat layer, or (a) Further, the present invention relates to a phase difference control board that is both of the above (b).

  5th invention has the structure of any one of 1st-4th invention, and the phase difference control board | substrate which has a transparent electrode layer on one side, and another board | substrate which has an electrode layer, The electrode which the said both board | substrate has The present invention relates to a liquid crystal display characterized in that the layers face each other and face each other, and a liquid crystal layer is sealed between the two substrates.

  According to a sixth aspect of the present invention, an outer peripheral portion of the substrate is formed by laminating a retardation control layer by applying a composition for forming a retardation control layer on a substrate, and then cleaning the end surface using a solvent. The retardation control substrate is characterized in that the retardation control layer is removed to form a margin in the outer peripheral portion of the substrate, and / or the retardation control layer is flattened from the central portion to the outer peripheral portion. It is related with the manufacturing method.

  In the seventh invention, after the end face cleaning is performed according to the method of the seventh invention, the overcoat layer is laminated on the substrate including the retardation control layer by using the overcoat layer forming composition. Then, by performing end face cleaning using a solvent, the overcoat layer in the outer peripheral portion of the substrate is removed to form a margin in the outer peripheral portion of the substrate, and / or the overcoat layer is formed in the center thereof. It is related with the manufacturing method of the phase difference control board characterized by planarizing from a part to an outer peripheral part.

  According to the invention of claim 1, the retardation control layer laminated on the substrate is laminated with a margin left on the outer peripheral portion of the substrate or / and the outer periphery from the central portion of the retardation control layer. Since it is flat over the part, a phase difference control substrate capable of realizing a uniform cell gap with the counter substrate over the entire display area can be provided.

  According to the invention of claim 2, in addition to the effect of the invention of claim 1, the thickness of the outer peripheral portion of the retardation control layer is defined as +10 μm or less compared to the thickness of the center portion, so that the cell gap uniformity is further increased. It is possible to provide a phase difference control board capable of increasing the height.

  According to the invention of claim 3, in addition to the effect of the invention of claim 1 or 2, it is possible to provide a phase difference control substrate that enables color display of an image by laminating a color filter layer. it can.

  According to the fourth aspect of the present invention, the overcoat layer is laminated on the surface opposite to the substrate side of the retardation control layer, and the overcoat layer has a margin on the outer periphery of the substrate. Since it is laminated and / or is flat from the center to the outer periphery of the overcoat layer, a uniform cell gap is realized between the counter substrate and the entire display area. It is possible to provide a phase difference control board that can be used.

  According to the invention of claim 5, since the retardation control substrate capable of exhibiting the effects of any of claims 1 to 4 is used, the film thickness of the outer peripheral portion of the retardation control layer is increased. This eliminates the disadvantages caused by this phenomenon, and does not involve cutting, so that there is no trouble caused by cutting, and a uniform cell gap can be realized over the entire display area. A liquid crystal display can be provided.

  According to the invention of claim 6, the phase difference control layer is formed on the substrate, and then the end face cleaning is performed, so that the phase difference control layer on the outer periphery can be removed or the thickness can be reduced. Thus, it is possible to provide a method for manufacturing a phase difference control board that can easily eliminate the problems caused by the rise of the phase difference control layer.

  According to the invention of claim 7, even when the overcoat layer is further laminated, the overcoat layer on the outer peripheral portion can be removed or the thickness can be reduced by cleaning the end face. It is possible to provide a method of manufacturing a phase difference control substrate that can easily eliminate the troubles caused by the overcoating of the overcoat layer.

  FIG. 1 and FIG. 2 are views showing examples of the retardation control plate of the present invention and examples of a laminated structure of a liquid crystal display using these. The phase difference control plate 1 shown in FIGS. 1 (a) and 2 (a) is the same as that shown in FIG. 4 (a) except that a removal line 5a or 5b is added.

  As shown in FIG. 1A, the phase difference control plate 1 is formed by laminating a color filter (indicated by “CF” in the figure) layers 3 on a substrate 2 in two horizontal directions. A retardation control layer 4 is laminated on the substrate 2 including the color filter layer 3, and the retardation control layer 4 is formed by applying and drying a coating composition for forming the retardation control layer. The surface (upper surface in the drawing) of the phase difference control layer 4 has a flat portion 4 b except for the outer peripheral portion of the substrate 2, and the film thickness of the phase difference control layer 4 at the outer peripheral portion of the substrate 2. It has a thickened raised portion 4a.

  In the example described with reference to FIG. 1, removal is performed with a removal line 5 a extending perpendicularly to the substrate 2 from the boundary between the raised portion 4 a and the flat portion 4 b on the surface of the formed retardation control layer 4 as a boundary. The phase difference control layer 4 in the portion outside the line 5a is removed, the exposed portion 2a is formed in the portion of the surface of the substrate 2 where the raised portion 4a is present, and the phase difference control layer 4 consisting only of the flat portion 4b is formed. A phase difference control substrate 1a having the same is formed (FIG. 1B).

  An example in which a liquid crystal display is configured using the phase difference control substrate 1a shown in FIG. 1B will be described with reference to FIG. 1C. The counter substrate 7 faces the phase difference control substrate 1a and remains. At the outer periphery of the phase difference control layer 4, the phase difference control substrate 1a and the counter substrate 7 are bonded together via a sealant 6 to perform sealing, and after sealing, each chip is cut and then the phase difference control substrate 1a. A liquid crystal layer 5 is sealed in a gap formed by a seal between the liquid crystal display 5 and the counter substrate 7 to form a liquid crystal display 5a having a uniform cell gap (FIG. 1D). In this case, since the cutting process is performed after the sealing step, there is no risk of contamination of the surface of each substrate in contact with the liquid crystal of the liquid crystal display 5a due to glass pieces or the like generated during the cutting. In addition, bead-like spacer particles may be dispersed for the purpose of keeping the gap interval, that is, the cell gap constant. An electrode layer for driving the liquid crystal layer and an alignment layer for aligning the liquid crystal are usually formed inside the retardation control substrate and the counter substrate. The electrode layer on the retardation control substrate side is a transparent electrode layer. Preferably there is.

  Next, in the example described with reference to FIG. 2, the removal line 5 b (FIG. 2) extending from the surface of the flat portion 4 b toward the outer periphery of the upper portion of the raised portion 4 a on the surface of the phase difference control layer 4. Using (a)) as a boundary, thinning processing is performed to remove the portion above the removal line 5b on the outer periphery of the phase difference control layer 4, and the surface of the substrate 2 rises to the portion where the raised portion 4a was present. A slight raised portion 4a ′ which is a trace of the portion is left. In this example, the distance between the removal line 5b and the surface of the substrate 2 is assumed to move away from the substrate 2 as it approaches the outside of the substrate 2, and as the outer peripheral portion goes outward in addition to the flat portion 4b. A phase difference control substrate 1b on which the phase difference control layer 4 having the slightly inclined portion 4a ′ is formed is obtained (FIG. 2B).

  Similarly to the phase difference control substrate 1a shown in FIG. 1B, the phase difference control substrate 1b shown in FIG. 2B also faces the phase difference control substrate 1b and the counter substrate 7, and the phase difference control layer 4a. In the outer peripheral portion of the substrate, sealing is performed by bonding through a sealant 6, and after sealing, the chip is cut for each chip, and then a liquid crystal layer is sealed between them to form a liquid crystal display 5 b (FIG. 2C )). Also in this case, since the cutting process is performed after the sealing step, there is no risk of contamination of the surface of each substrate in contact with the liquid crystal of the liquid crystal display 5a due to glass pieces or the like generated at the time of cutting. The spacer particles, the electrode layer, and the alignment layer are the same as described with reference to FIG.

  At this time, when the outer peripheral sealing agent 6 is provided on the inclined portion 4a ′, the distance between the phase difference control substrate 1b and the counter substrate 7 in the outer peripheral portion is slightly wider in the outer peripheral portion (FIG. 2C). ) Since the height of the inclined portion 4a ′ is lower than the height of the original raised portion 4a, the nonuniformity of the cell gap is improved.

  In the above, the inclined portion 4a 'may be formed so as to be slightly thinner toward the outside, or may be formed in the same plane as the flat portion 4b, not the inclined portion 4a'. Here, when the thinning process for thinning the outer peripheral portion of the phase difference control layer 4 is performed, the thickness (maximum thickness) of the outer peripheral portion of the phase difference control layer 4 is the central portion of the phase difference control layer. It is preferable to planarize to be +10 μm or less compared to the thickness. Of course, ideally, the difference is more preferably 0 μm.

  FIG. 3 is a plan view showing the relationship between the phase difference control board 1 having the raised portion 4a and the phase difference control board 1a (or 1b) of the present invention. In the example shown in FIG. 3, the color filter layer 3 is arranged by laminating two screens in the left-right direction and three screens in the up-down direction, and the phase difference control layer 4 is laminated. The phase difference control substrate 1 is configured to have a raised portion 4a having a thick film on the outer periphery of the substrate.

  Therefore, the relationship where the raised portion 4a is raised relative to the other flat portions 4b of the phase difference control layer 4 only has to be eliminated. Therefore, the raised portion 4a of the phase difference control layer 4 is formed over the entire thickness of the substrate. May be completely removed or only a portion protruding from the flat portion 4b of the raised portion 4a may be removed without causing a change in the planar area of the phase difference control layer 4, and a slight rise The portion 4a ′ or a completely flat portion may be used. Further, when only the latter protruding portion is removed, the removed portion may be thinner than the flat portion 4b.

  Regardless of what has been described with reference to FIGS. 1 and 2, removing the raised portion 4 a of the phase difference control layer 4 from the surface to the substrate surface means that the portion of the raised portion 4 a near the center of the substrate 2 is slightly. Including remaining state. In this case, a protruding portion in which a part of the raised portion 4a protrudes from the flat portion is formed on the outer peripheral portion, but the protruding height of the protruding portion is +10 μm or less compared to the thickness of the central portion of the phase difference control layer. Is preferable, and 0 μm is more preferable. Moreover, removing the part which protruded rather than the flat part 4b of the bulging part 4a already mentioned includes that the part which protruded remains a little. The removal of the raised portion 4a from the surface to the substrate surface and the removal of the protruding portion of the raised portion 4a from the flat portion 4b are sufficient if only one of them is performed. Also good.

  In the above description, the phase difference control substrate 1 (including 1a and 1b) has been described as an example in which the color filter layer 3 and the phase difference control layer 4 are sequentially laminated on the substrate 2. The control layer 4 may be a single layer or multiple layers. Since the present invention is valid as long as at least the phase difference control layer 4 is laminated on the substrate 2, the color filter layer 3 may be omitted. Conversely, in addition to the substrate 2 and the phase difference control layer 4, there are various types. These layers may be laminated. Examples of the various layers include a black matrix, an overcoat layer, an alignment layer, or an electrode layer including the color filter layer 3. For example, the black matrix is laminated between the substrate and the color filter layer 3, the overcoat layer is laminated on the surface opposite to the substrate 2 side of the retardation control layer 4, and the electrode layer and the alignment layer are On the side opposite to the substrate side of the phase difference control layer 4, the electrode layer and the alignment layer are laminated in this order from the phase difference control layer 4 side.

  When various layers other than the above-described phase difference control layer 4 are also provided by coating, there is a problem that the layer thickness increases from the end surface of the substrate to the outer peripheral portion to form a raised portion. In such a case, it is preferable to remove the raised portion by the same method as that for removing the raised portion 4a of the phase difference control layer 4. In particular, when an overcoat layer is laminated on the surface opposite to the substrate 2 side of the phase difference control layer 4, the overcoat layer is often formed on the entire surface, and the thickness is also thick. It is preferable to remove the swelled portion because there is a great trouble caused by the occurrence of the above. The removal of the raised portion of the overcoat layer is either one of (a) removing the raised portion from the surface to the substrate surface, or (b) removing the portion protruding from the flat portion of the raised portion. Or both (a) and (b) may be performed. As described above with reference to FIGS. 1 (c) and 2 (c), the liquid crystal display with improved cell gap uniformity is obtained by removing the raised portion of the overcoat layer. Can be obtained.

  Examples of the substrate 2 of the retardation control substrate in the present invention include inorganic base materials such as glass, silicon, and quartz, and organic base materials as listed below. Examples of organic base materials include acrylics such as polymethyl methacrylate, polyamide, polyacetal, polybutylene terephthalate, polyethylene terephthalate, polyethylene naphthalate, triacetyl cellulose, or syndiotactic polystyrene, polyphenylene sulfide, polyether ketone, polyether ether Ketone, fluororesin, polyether nitrile, etc., polycarbonate, modified polyphenylene ether, polycyclohexene, polynorbornene resin, etc., or polysulfone, polyethersulfone, polysulfone, polyarylate, polyamideimide, polyetherimide, or heat Examples include plastic polyimide, but polypropylene and other common polypropylene. Made of sticks can also be used. Although there is no limitation in particular in the thickness of the board | substrate 2, a thing of about 5 micrometers-1 mm is used according to a use, for example.

  The black matrix is formed by applying a paint-type resin composition containing a black colorant to one side and solidifying it once, and then applying a photoresist, or a paint-type photosensitive resin containing a black colorant. It can form by performing application | coating, exposure, and image development using a conductive resin composition, Therefore, it can comprise from the resin composition containing a black coloring agent.

  Alternatively, the black matrix is a two-layer chrome black matrix having a laminated structure of CrOx / Cr (x is an arbitrary number, “/” represents a laminated structure), or CrOx / CrNy / Cr (with reduced reflectance). x, y are arbitrary numbers), and a three-layer chrome black matrix or the like is formed by various methods such as vapor deposition, ion plating, or sputtering. It can also be formed by forming a thin film and patterning it using photolithography, electroless plating, or printing using black ink composition. The thickness of the black matrix is about 0.2 μm to 0.4 μm when formed as a thin film, and about 0.5 μm to 2 μm when formed by a printing method.

  Each color pattern of the color filter layer 4 may be provided for each aperture of the black matrix, but for convenience, it is provided in a strip shape from the front side to the back side in FIG. May be. The color filter layer 4 may be formed by preparing an ink composition colored in a predetermined color and printing it for each color pattern. However, a paint type containing a colorant of a predetermined color may be used. It is more preferable to carry out by a photolithography method using the photosensitive resin composition. The thickness of the color filter layer 4 is about 1 μm to 5 μm.

  Prior to forming the phase difference control layer 4, an alignment film is formed as necessary. The alignment film is for aligning liquid crystal polymers used for constituting the phase difference control layer 4 in a predetermined direction. A resin composition in which a resin film such as a polyamide resin or a polyimide resin is dissolved. Can be formed by applying rubbing that rubs in a predetermined direction with a roller or the like around which the cloth is wound. In addition, when stacking two layers of the phase difference control layer 4, it is preferable to stack an alignment film between the first layer and the second layer.

  The phase difference control layer 4 can be formed by polymerizing a polymerizable liquid crystalline monomer when the phase difference control layer 4 whose optical axis is horizontal to the layer is formed, specifically, The composition can be formed by applying a composition for forming a retardation control layer, which is a photopolymerizable liquid crystal composition in which a photopolymerization initiator is blended with a monomer, and exposing to ultraviolet rays, and the optical axis is perpendicular to the layer. When forming the retardation control layer 4, it is similarly formed using a composition for forming a retardation control layer, which is a photopolymerizable liquid crystal composition containing a chiral agent, preferably a polymerizable chiral agent. Can do.

  As the polymerizable liquid crystal monomer, for example, known ones as disclosed in JP-T-10-508882 and as the polymerizable chiral agent can be used, for example, as disclosed in JP-A-7-258638. More specifically, examples of the polymerizable liquid crystal monomer include those represented by the following formulas (1) to (11), and examples of the chiral agent include those represented by the following formulas (12) to (14). The following can be exemplified.

上記各式の表記において、「式１１」〜「式１４」中のいずれもメチレン基の数（アルキレン基の鎖長）を示すａ〜ｅはいずれも整数であって、まず、ａ、ｂが、各々個別に２〜１２であり、より好ましくは４〜１０、特に好ましくは６〜９であり、ｃ、ｄはいずれも２〜１２であり、より好ましくは４〜１０であり、特に好ましくは６〜９であり、さらにｅは２〜６である。また、「式１２」および「式１３」中のＹは、「化１５」および「化１６」に示す「式ｉ」〜「式ｘｘｉｖ」のいずれかであって、より好ましくは「式ｉ」、「式ｉｉ」、「式ｉｉｉ」、「式ｖ」、もしくは「式ｖｉｉ」のいずれかである。

In the above formulas, “a” to “e” indicating the number of methylene groups (chain length of the alkylene group) in “Formula 11” to “Formula 14” are all integers. , Individually 2 to 12, more preferably 4 to 10, particularly preferably 6 to 9, and c and d are both 2 to 12, more preferably 4 to 10, particularly preferably. 6-9, and e is 2-6. Y in “Formula 12” and “Formula 13” is any one of “Formula i” to “Formula xxiv” shown in “Formula 15” and “Formula 16”, and more preferably “Formula i”. , “Formula ii”, “formula iii”, “formula v”, or “formula vii”.

  In order to form the phase difference control layer 4, the photopolymerizable liquid crystal composition as described above is used, dissolved or diluted with a solvent as necessary, and spin coating method, die coating, slit coating, or other appropriate methods. According to the method, coating is performed on the target surface, and polymerization is performed by irradiating with ultraviolet rays.

  The obtained phase difference control layer 4 has a bulging portion 4a on the outer peripheral portion, which is a problem, so as described above, the bulging portion 4a is removed from the surface to the substrate surface, Or the part which protruded rather than the flat part 4b of the rising part 4a is removed. These removals can be performed before or after polymerization when the retardation control layer 4 is formed using a photopolymerizable liquid crystal composition. When the phase difference control layer 4 is a multilayer, these removals may be performed for each layer or after the multilayer phase difference control layer 4 is laminated.

  In order to perform the above-described removal, it is preferable to clean the end face of the substrate using an organic solvent. The organic solvent is formed between the raised portion 4a and the flat portion 4b of the retardation control layer 4 described with reference to FIG. It blows out only to the part near the edge part of the board | substrate 2 rather than the removal line 5a set to the boundary, and makes it melt | dissolve with an organic solvent. In order to prevent the blown-out organic solvent from flowing closer to the center of the substrate 2 than the removal line 5a, it is preferable to perform evacuation by vacuum or reduced pressure from the end side of the substrate 2. For example, an end portion of the substrate 2 having the phase difference control layer 4 is inserted into the region where one side is open, such as a U-shaped cross section from the opened side, The organic solvent is blown out by the nozzle installed downward on the inner surface corresponding to the wire, and exhausted by vacuum or reduced pressure from the exhaust port or decompression port installed at the position corresponding to the vertical line on the right side of the “U” By restricting the flow of the blown organic solvent in one direction, the organic solvent is blown continuously, and if necessary, the substrate 2 having the phase difference control layer 4 is moved continuously, The raised portion 4a of the retardation control layer 4 can be removed by end face cleaning, or the thickness of the raised portion 4a can be reduced. In addition, the rising portion of the phase difference control layer 4 provided on the lower side of the substrate 2 can be removed by installing the nozzle upward on the inner surface corresponding to the lower line of the “U”. The cleaning of the end face of the substrate using the organic solvent may be performed using a nozzle that is inclined toward the end side of the substrate 2, and even if it is performed in this way, the blown-out organic solvent is more than the predetermined position. Flowing toward the center of the substrate 2 can be prevented.

  Almost all organic solvents can be used for end face cleaning. For example, ketone solvents such as acetone, methyl ethyl ketone, or cyclohexanone, ethyl acetate, propylene glycol monomethyl ether acetate, or methoxybutyl acetate. An ester solvent such as methanol, ethanol or isopropanol, a halogen solvent such as chloroform, methylene chloride or carbon tetrachloride, or tetrahydrofuran, benzene, toluene or xylene can be used.

  In particular, when the substrate surface is cleaned with an organic solvent after the retardation control layer 4 is formed by using a liquid crystalline monomer and cured by ultraviolet exposure or the like, among the above organic solvents, the comparison is performed. It is more preferable to use a solvent having a high general solubility, such as tetrahydrofuran, chloroform, methylene chloride, N-methylpyrrolidone, γ-butyrolactone, dimethylacetamide, or dimethylformamide.

  In order to more reliably clean the end face of the substrate, friction cleaning performed by bringing a brush, a sponge or the like into contact can be used in combination.

  The above removal is performed by using a sandpaper or the like, which is obtained by spreading and adhering appropriate abrasive grains on a sheet, and a chemical polishing method or a mechanical polishing method, or a mechanochemical using them in combination. Polishing (also referred to as MCP or chemical mechanical polishing (CMP)) can be performed. The chemical polishing method is performed, for example, by supplying an etching liquid as an abrasive to an abrasive member made of a foam such as cloth, non-woven fabric, or polyurethane resin. Can be used. The mechanical polishing method uses, for example, cloth, non-woven fabric, or polyurethane resin as a polishing member, impregnated with fine powder of colloidal silica or cerium oxide as an abrasive, or disperses colloidal silica or cerium oxide. This is performed by supplying the dispersed liquid. In any case, the polishing member is brought into contact with the outer peripheral portion of the phase difference control layer while relatively moving the object and the polishing member, and the polishing agent is supplied as necessary. These chemical polishing methods, mechanical polishing methods, or mechanochemical polishing using them in combination, or ordinary polishing methods, are used when the retardation control layer 4 is formed using a polymerizable liquid crystalline monomer. It is preferable to carry out after curing by exposure or the like.

  The overcoat layer can also be formed using a transparent thermoplastic resin for a normal paint binder, but preferably an acrylate-based, methacrylate-based, polyvinyl cinnamate-based, or cyclized rubber-based reactive agent. It is preferably made of a cured product of an ionizing radiation curable resin having a vinyl group (actually, an electron beam curable resin or an ultraviolet curable resin, which is often the latter). The overcoat layer is applied and dried using the overcoat layer forming composition, or the ionizing radiation curable resin is mixed with a solvent, a diluent, a monomer, or the like, and an appropriate additive as necessary. It can be formed by uniformly applying and drying an ionizing radiation-curable composition for forming an overcoat layer obtained by mixing, and then curing it by irradiation with ionizing radiation. The overcoat layer is also subjected to end face cleaning similar to that performed for the retardation control layer 4 to remove the overcoat layer on the outer periphery of the substrate 2 or to reduce the thickness of the outer periphery of the overcoat layer. It can be thinned and flattened from the center portion to the outer peripheral portion of the overcoat layer, and the same effect as when the phase difference control layer 4 without the overcoat layer is end-face cleaned can be produced.

  The phase difference control substrate of the present invention will be specifically described below by way of example in which a phase difference control layer is laminated on a substrate via a color filter layer.

Each photosensitive resin composition (hereinafter referred to as a photoresist) for forming each color pattern of a black matrix and a color filter layer formed on a substrate was prepared. Each photoresist is prepared by adding beads to a pigment, a dispersant, and a solvent, using a paint shaker as a disperser, dispersing for 3 hours, and then removing the beads, a polymer, a monomer, an additive, It was prepared by mixing a resist composition comprising an initiator and a solvent. The composition of each photoresist is as shown below, and the number of parts is based on mass.
Photoresist for forming black matrix, black pigment, 14.0 parts (manufactured by Dainichi Seika Kogyo Co., Ltd., TM Black # 95550)
・ Dispersant ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ 1.2 parts (Bic Chemie Co., Disparvic 111)
・ Polymer ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ 2.8 parts (made by Showa Polymer Co., Ltd., (meth) acrylic resin, product number; VR60)
・ Monomer ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ 3.5 parts (manufactured by Sartomer Co., Ltd., polyfunctional acrylate, product number: SR399)
・ Additive (dispersibility improver) ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ 0.7 parts (Chemical L-20, manufactured by Soken Chemical Co., Ltd.)
Initiator ... 1.6 parts (2-benzyl-2-dimethylamino-1- (4-morpho Linophenyl) -butanone-1)
・ Initiator (4,4′-diethylaminobenzophenone) ··· 0.3 parts · Initiator (2,4-diethylthioxanthone) ··· 0.1 parts · Solvent ( Ethylene glycol monobutyl ether) ... 75.8 parts Photoresist for forming red pattern Red pigment (CIPR254) ... 3.5 (Ciba Specialty Chemicals Co., Ltd., Chromoval DPP Red BP)
・ Yellow pigment (CI PY139): 0.6 part (BASF, Pariotor Yellow D1819))
・ Dispersant ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ 3.0 parts (Zeneca Co., Ltd., Solsperse 24000)
・ Polymer 1 (below) ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ 5.0 parts ・ Monomer ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・..... 4.0 parts (manufactured by Sartomer, polyfunctional acrylate, product number: SR399)
・ Initiator ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ 1.4 parts (Ciba Specialty Chemicals Co., Ltd., Irgacure 907)
・ Initiator ... 0.6 parts (2,2'-bis (o-chlorophenyl) -4,5 , 4 ′, 5′-tetraphenyl-1,2′-biimidazole)
・ Solvent ... 80.0 parts (propylene glycol monomethyl ether acetate)
In addition, the polymer 1 is 100 mol% of the copolymer in which the polymer 1 is benzyl methacrylate: styrene: acrylic acid: 2-hydroxyethyl methacrylate = 15.6: 37.0: 30.5: 16.9 (molar ratio). On the other hand, 16.9 mol% of 2-methacryloyloxyethyl isocyanate is added, and the weight average molecular weight is 42500, and the same applies thereafter.
Green Pattern Forming Photoresist Instead of the red pigment and yellow pigment in the above red pattern forming photoresist, the following pigments were used in the following amounts.
・ Green pigment (CIPG7) ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ 3.7 parts (Seika Fast Green 5316P manufactured by Dainichi Seika)
-Yellow pigment (CI PY139) ... 2.3 parts (manufactured by BASF, Paliotor Yellow D1819)
Blue pattern forming photoresist Instead of the red pigment, yellow pigment, and dispersant in the above red pattern forming photoresist, the following were used in the following amounts.
-Blue pigment (CI PB15: 6) ... 4.6 parts (BASF Heliogen Blue L6700F))
・ Purple pigment (CI. PV23) ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ 1.4 parts (Clariant, Foster Palm RL-NF)
Pigment derivative: 0.6 parts (Solsperse 12000 manufactured by Zeneca)
・ Dispersant ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ 2.4 parts (Solsparse 24000 manufactured by Zeneca)
As a substrate, a melt-formed borosilicate thin plate glass having a thickness of 0.7 mm (manufactured by Corning, USA, product number: 7059) was prepared, washed, and then a black matrix forming photoresist was formed on the substrate by spin coating. After application, pre-baking is performed under conditions of temperature: 90 ° C. and heating time: 3 minutes, and after pre-baking, UV exposure is performed through a predetermined pattern so that the irradiation dose becomes 100 mJ / cm ^2. , Spray development using 0.05% KOH aqueous solution was performed for 60 seconds, and then post-baking was performed under the conditions of temperature: 200 ° C. and heating time: 30 minutes, and the thickness having an aperture corresponding to a pixel was 1 A black matrix of 2 μm was formed.

Next, a black matrix is formed on the substrate, a red pattern forming photoresist is applied by spin coating, prebaked under conditions of a temperature of 80 ° C. and a heating time of 5 minutes, and then predetermined. Through the pattern, alignment exposure is performed so that the irradiation dose from the ultraviolet light source becomes 300 mJ / cm ^2, and after the exposure, spray development using a 0.1% KOH aqueous solution is performed for 60 seconds, and then the temperature; 200 ° C., and Post baking was performed under the condition of heating time: 60 minutes, and a red pattern having a thickness of 2.6 μm was formed at a position corresponding to a predetermined opening of the black matrix.

  Subsequently, in the same manner as the red pattern forming step, a green pattern having a thickness of 2.6 μm is formed using a green pattern forming photoresist, and then a blue pattern forming photoresist is used. .6 μm blue pattern is formed by arranging red, green and blue color patterns at positions corresponding to different apertures of the black matrix, and a pattern in which three patterns of red, green and blue are arranged A filter layer was formed.

  A black matrix and a color filter layer are formed on a substrate, and a soluble polyimide resin-based ink composition for forming an alignment film (manufactured by JSR Corporation, product number: AL1254) is patterned in a required shape by a flexographic printing method. After printing, printing and drying to remove the solvent, baking is performed under the conditions of temperature: 200 ° C. and heating time: 1 hour, and after baking, the surface is rubbed to obtain an alignment film having a thickness of 700 mm Was formed on the entire surface of the substrate including the color filter layer. Although not provided here, a transparent overcoat layer may be interposed between the color filter layer and the alignment film.

  Separately, photosensitive resin compositions (1) and (2) for forming a retardation control layer were prepared. As the photosensitive resin composition (1) for the A plate, a liquid crystal material having a mesogen at the center and a polymerizable acrylate group at both ends and a spacer between the mesogen at the center and the acrylate groups at both ends And 1 part of a photopolymerization initiator (1-hydroxycyclohexyl phenyl ketone, manufactured by Ciba Specialty Chemicals, Inc., Irgacure 184) and 25 parts of toluene as a solvent were prepared. In addition to the same composition as the photosensitive resin composition (1), the photosensitive resin composition (2) for the C plate further contains 5 parts of a chiral material having polymerizable acrylate groups at both ends. Prepared by blending and mixing.

  The prepared ink is applied onto the alignment film using a spin coating method, and after coating, the substrate is heated on a hot plate at a temperature of 100 ° C. for 5 minutes, and a dry coating having a liquid crystal state of 1.0 μm in thickness is applied. A membrane was obtained. This dry coating film has a raised portion where the thickness of the portion within 3 cm from the peripheral edge of the substrate is 14 μm at the maximum.

  For the obtained dried coating film, an end face cleaning device (manufactured by Tokyo Ohka Kogyo Co., Ltd., product number: EBR) is used, and propylene glycol monomethyl ether acetate is used as the cleaning liquid, within 3 cm from the peripheral edge of the substrate. Cleaning treatment by spraying the cleaning liquid was performed over the entire area until the film thickness of the dried coating film reached 11 μm. The film thickness was measured after exposure using a stylus type film thickness meter (manufactured by KLA-Tencor Corp., product name: Alphastep).

After the above cleaning treatment, the dried coating film is irradiated with ultraviolet rays (wavelength: 365 nm, irradiation energy: 10 J / cm ² ), and after fixing the liquid crystal state, the whole substrate is placed on a hot plate at a temperature of 200 ° C. The curing reaction was completely advanced by heating for 10 minutes to form an A plate retardation control layer having a thickness of 1.0 μm in the effective display area.

  After the A plate was formed as described above, the photosensitive resin composition (2) was used, and a dry coating film was obtained in the same manner as performed using the photosensitive resin composition (1). Thereafter, washing treatment and ultraviolet irradiation were sequentially performed to form a C plate retardation control layer having a thickness of 2.5 μm. The cleaning process was performed over the entire area within 3 cm from the peripheral edge of the substrate until the total thickness of each of the A plate and the C plate reached 13.5 μm. In this case as well, for more reliable cell assembly when applied to a liquid crystal cell, it is preferable that the dried coating film in the entire area within 3 cm from the substrate end face is completely removed.

  After forming the black matrix, the color filter layer, and the two phase difference control layers, that is, the color filter substrate with the phase difference control layer in which the A plate and the C plate are laminated, as described above, An alignment film is formed on the plate, spacer beads (Sekisui Chemical Co., Ltd., trade name: “Micropearl”) are sprayed in a dry state, an outer peripheral sealant is applied to the outer periphery of the effective display area, and a counter substrate is formed. And a cell for liquid crystal encapsulation was obtained.

  In the same manner as in Example 1, a black matrix, a color filter layer, an A plate, and a C plate were sequentially formed on a substrate, and then an overcoat layer was formed on the entire surface of the C plate as follows.

To form the overcoat layer, a protective film forming ink prepared using an acrylic resin (manufactured by JSR, product number: JNPC80) is applied by spin coating, temperature: 100 ° C., heating time After pre-baking under conditions of 5 minutes, washing treatment, ultraviolet irradiation and post-baking were performed to form an overcoat layer having a thickness of 1.5 μm. The cleaning process is performed in the same manner as in the case of the A plate and the C plate in Example 1, and each of the A plate, the C plate, and the overcoat layer is spread over the entire area within 3 cm from the peripheral edge of the substrate. This was performed until the total film thickness reached 15 μm. Ultraviolet irradiation was performed on the entire surface under conditions of 300 mJ / cm ² , and post-baking was performed under the conditions of temperature: 200 ° C., heating time: 60 minutes.

It is a figure which shows the phase difference control board which has a phase difference control layer from which the outer peripheral part was removed. It is a figure which shows the phase difference control board which has a phase difference control layer by which the outer peripheral part was thinned. It is a figure which shows the swelling part of a phase difference control layer. It is a figure which shows the conventional phase difference control board.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Phase difference control board 2 ... Board 3 ... CF (color filter) layer 4 ... Phase difference control layer 5 ... Removal line 6 ... Outer peripheral part sealant 7 ... Opposite substrate 8 ... Spacer

Claims (7)

  The substrate has a laminated structure in which at least one phase difference control layer made of a liquid crystalline polymer is laminated, and the phase difference control layer is (1) laminated with a margin on the outer periphery of the substrate. Or (2) a phase difference control substrate that is flat from the center to the outer periphery of the phase difference control layer, or is both the above (1) and (2) .   2. The retardation control layer is flat from the center to the outer periphery, and the thickness of the outer periphery of the retardation control layer is +10 μm or less compared to the thickness of the center. Phase difference control board.   The phase difference control substrate according to claim 1, wherein a color filter layer is laminated in addition to the phase difference control layer.   The overcoat layer is laminated | stacked on the surface on the opposite side to the said substrate side of the said phase difference control layer of the phase difference control board in any one of Claims 1-3, The said overcoat layer is (a). The substrate is laminated with leaving a blank space, or (b) is flat from the center to the outer periphery of the overcoat layer, or (a) and (b) A phase difference control board characterized by being both.   The phase difference control substrate having the configuration according to any one of claims 1 to 4 and having a transparent electrode layer on one side and another substrate having an electrode layer are arranged such that the electrode layers of both the substrates are inside. A liquid crystal display having a liquid crystal layer sealed between the substrates.   After laminating the phase difference control layer by coating with a composition for forming a phase difference control layer on the substrate, the phase difference control layer in the outer peripheral portion of the substrate is washed by using a solvent. A method of manufacturing a phase difference control substrate, wherein a blank is formed on the outer peripheral portion of the substrate and / or the phase difference control layer is planarized from the central portion to the outer peripheral portion. After end face cleaning is performed according to the method of claim 6, the overcoat layer-forming composition is applied onto the substrate including the retardation control layer, the overcoat layer is laminated, and then a solvent is used. By cleaning the end surface, the overcoat layer on the outer peripheral portion of the substrate is removed to form a margin in the outer peripheral portion of the substrate, or / and the overcoat layer is flattened from the central portion to the outer peripheral portion. A method of manufacturing a phase difference control board.

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