JP4157537B2 - Method for manufacturing color filter and method for manufacturing liquid crystal display device - Google Patents

Description

  The present invention relates to a color filter and a liquid crystal display device, and more particularly to a liquid crystal display device excellent in display quality and a color filter used therefor.

  In recent years, a color liquid crystal display device has attracted attention as a flat display. As an example of a color liquid crystal display device, a black matrix, a colored layer composed of a plurality of colors (usually three primary colors of red (R), green (G), and blue (B)), a common transparent electrode layer, and an alignment layer are provided. A transmissive liquid crystal in which a color filter and a counter electrode substrate including a thin film transistor (TFT element), a pixel electrode, and an alignment layer face each other with a predetermined gap and a liquid crystal material is injected into the gap to form a liquid crystal layer. There is a display device. There is also a reflective liquid crystal display device in which a reflective layer is provided between the color filter substrate and the colored layer.

  In such a color liquid crystal display device, when the alignment state of the liquid crystal changes due to a liquid crystal alignment failure, a voltage change applied to the liquid crystal, a voltage variation in the display surface, or the like, a display failure occurs. This display defect includes the following image sticking and white unevenness.

  Image sticking occurs when the voltage is lowered or turned off after a voltage is applied to the same pixel for a certain period of time, so that the transmittance of this pixel differs from the transmittance of the surrounding pixels for which the voltage was not applied for a certain period of time. This is a phenomenon in which the uneven state is recognized, and the uneven state continues even after being left for a long time. In a burn-in phenomenon in a normally white panel, a pixel to which a voltage is applied for a certain time appears darker than surrounding pixels. Such seizure phenomenon is caused by the fact that the ionic substance adheres to the electrode during voltage application, and the ionic substance remains adsorbed on the electrode even if the voltage is released next, and the voltage due to this ionic substance is liquid crystal. It is thought that this is caused by continuing to act on

  Further, the white unevenness is a phenomenon in which the uneven state is recognized because a part of the display area does not become zero transmittance when a black screen is displayed by applying a voltage. This is because the voltage applied between the electrodes should be kept constant, but if there is an ionic substance in the liquid crystal, the ionic substance moves, that is, the current flows, so the voltage between the electrodes The cause is thought to be descending.

  It is considered that the ionic substance that causes the display defect phenomenon as described above does not stay on the electrode but easily moves in the liquid crystal layer. Various sources can be considered as the source of this ionic substance. In order to prevent display defects, impurities from chemicals, air, pure water, etc. used in the manufacturing process, management from equipment, human bodies, etc. Dust generation management and process conditions are optimized. Further, impurities such as residues are removed by cleaning the surface of the color filter or the counter electrode substrate, or by irradiating with ultraviolet rays or polishing the surface in the manufacturing process.

  Although such a response makes it difficult for the display failure phenomenon to occur, there is a problem that the probability of the display failure is still high under severe display conditions such as long-time display and high temperature and high humidity.

  The present invention has been made in view of the circumstances as described above, and provides a color filter that can more reliably prevent an ionic substance from being mixed into a liquid crystal layer, and a liquid crystal display device excellent in display quality. With the goal.

  The present invention considers a resin member that is in contact with the liquid crystal layer of a liquid crystal display device as one of the sources of the ionic substance as described above, and has a correlation with a display defect due to the ionic substance transferred from the resin member into the liquid crystal layer. As a characteristic, attention is paid to the voltage holding ratio and the residual DC (ΔE) of the liquid crystal subjected to the impurity extraction process from the resin member.

That is, in order to achieve the above object, the present invention is formed so as to cover a substrate, a colored layer formed of a plurality of colors formed in a predetermined pattern on the substrate, and at least the colored layer. a transparent resin protective layer, in the manufacturing method of a color filter in which a plurality of Ru and a transparent resin pillar-shaped convex portion protruding than the resin protective layer formed on the predetermined portion, a voltage holding ratio of 95% or more and a residual A liquid crystal having a DC (ΔE) of 0.05 V or less is prepared, and as a resin member, the liquid crystal has a voltage holding ratio of 80% or more after being immersed in the liquid crystal and subjected to impurity extraction treatment, and residual DC. A resin member having (ΔE) of 0.5 V or less was selected, and the resin protective layer and the resin columnar protrusion were formed using the resin member .
As another aspect of the present invention, the common transparent electrode layer is formed on the resin protective layer .

The present invention provides a method for manufacturing a liquid crystal display device , comprising: a color filter and a counter electrode substrate facing each other so as to provide a gap through a seal member; and a liquid crystal layer sealed in the gap. Is configured to use a color filter manufactured by the above-described method for manufacturing a color filter .

Further, the present invention includes a color filter and an opposite electrode substrate opposite to each other to provide a gap via a sealing member, and a liquid crystal layer sealed in the gap, the opposite electrode substrate a resin light shielding layer In the method of manufacturing a liquid crystal display device including a semiconductor driving element, the color filter uses a color filter manufactured by the above-described method for manufacturing a color filter, has a voltage holding ratio of 95% or more, and residual DC (ΔE ) Is 0.05 V or less, and the liquid crystal has a voltage holding ratio of 80% or more after being immersed in the liquid crystal and subjected to impurity extraction treatment as a resin member, and residual DC (ΔE) A resin member having a voltage of 0.5 V or less is selected, and the resin light shielding layer is formed using the resin member .

According to the present invention, the resin protective layer and the resin columnar protrusions that constitute the color filter are made of resin in which the voltage holding ratio and the residual DC (ΔE) of the liquid crystal subjected to the impurity extraction process by the resin member are within a predetermined range In addition, the color filter of the present invention is used in the liquid crystal display device, and the resin member that is in contact with the liquid crystal layer or is closest to the liquid crystal layer through a thin film is extracted from the resin member. Since the resin material is such that the voltage holding ratio and residual DC (ΔE) of the liquid crystal subjected to is within a predetermined range, even under severe display conditions such as long-time display and high temperature and high humidity, Occurrence of display defects such as unevenness is prevented, and a liquid crystal display device having excellent display quality is possible.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, exemplary embodiments of the invention will be described with reference to the drawings.
[Color filter]
FIG. 1 is a schematic sectional view showing an example of an embodiment of a color filter of the present invention. In FIG. 1, a color filter 31 of the present invention includes a substrate 32, a black matrix 34 and a colored layer 35 formed on the substrate 32, and a transparent resin protective layer so as to cover the black matrix 34 and the colored layer 35. Further, transparent resin columnar convex portions 37 are formed at predetermined locations of the black matrix 34 so as to protrude from the resin protective layer 36.

  The color filter 31 is used in a liquid crystal display device in a state where a common transparent electrode layer and an alignment layer are provided on the resin protective layer 36. In this case, the resin member includes a resin protective layer 36 and a resin columnar convex portion 37. It is the closest position to the liquid crystal or a position in contact with the liquid crystal. In the present invention, the resin member that is in contact with the liquid crystal layer of the liquid crystal display device is considered as one of the sources of impurities such as ionic substances, and as a characteristic that correlates with display defects due to impurities transferred from the resin member into the liquid crystal layer, We paid attention to the voltage holding ratio and residual DC (ΔE) of the liquid crystal subjected to the impurity extraction treatment from the resin member.

  That is, in order to prevent white unevenness, which is one of display defects, it is necessary to maintain the voltage applied between the electrodes located on both sides of the liquid crystal layer. In the present invention, the resin protective layer 36 and the resin The columnar protrusion 37 is defined as a voltage holding ratio of the liquid crystal subjected to the impurity extraction treatment being 80% or more, preferably 90% or more, more preferably 95% or more. In order to prevent image sticking, which is one of display defects, an unnecessary voltage continues to be applied to the liquid crystal layer when the residual DC (ΔE) is reduced as much as possible and the voltage applied to the liquid crystal layer is released. It is necessary to prevent this. In the present invention, the residual DC (ΔE) of the liquid crystal subjected to the impurity extraction treatment between the resin protective layer 36 and the resin columnar protrusion 37 is 0.5 V or less, preferably 0.2 V or less, more preferably 0.1 V or less. Stipulate that Thereby, even under severe display conditions such as long-time display and high temperature and high humidity, display defects such as image sticking and white unevenness can be prevented, and a liquid crystal display device with excellent display quality can be achieved.

Here, the impurity extraction process, the measurement condition of the voltage holding ratio, and the measurement condition of the residual DC (ΔE) will be described.
(Impurity extraction process)
A resin member having a surface area of 4 cm ² is immersed in a liquid crystal having a volume of 0.2 ml and extracted at a temperature of 105 ° C. for 5 hours. In addition, the liquid crystal to be used has a voltage holding ratio of 95% or more measured under the following voltage holding ratio measuring conditions in the state before the impurity extraction treatment, and a residual measured under the following residual DC (ΔE) measuring conditions. A liquid crystal having a DC (ΔE) of 0.05 V or less is used.

(Voltage holding ratio measurement conditions)
As a layer structure, a measurement cell comprising a substrate / electrode / alignment layer / liquid crystal / alignment layer / electrode / substrate is prepared, and liquid crystal subjected to impurity extraction treatment is injected and measured under the following conditions.
・ Distance between electrodes: 5 to 15 μm
・ Applied voltage pulse amplitude: 5V
・ Applied voltage pulse frequency: 60 Hz
・ Applied voltage pulse width: 16.67 msec

(Residual DC (ΔE) measurement conditions)
In the voltage-capacitance hysteresis loop illustrated in FIG. 2, the residual DC (ΔE) is an electrostatic capacity defined by the formula (C0 + Cs) / 2 from the maximum capacitance (Cs) and the minimum capacitance (C0). This is a voltage shift amount in the capacitor (indicated by an arrow in FIG. 2). For the measurement, a measurement cell comprising a substrate / electrode / alignment layer / liquid crystal / alignment layer / electrode / substrate is prepared as a layer structure, and the liquid crystal subjected to the impurity extraction treatment is injected and measured under the following conditions.
・ Distance between electrodes: 5 to 15 μm
Liquid crystal used: Capacitance saturation voltage (Vs ′ in FIG. 2) is 10V
・ Voltage-Capacitance hysteresis loop measurement voltage range: -10V to + 10V

  When the color filter 31 is used in a liquid crystal display device, it is used in a state where a common transparent electrode layer or alignment layer is provided on the resin protective layer 36. The thickness of the common transparent electrode layer or alignment layer is as follows. However, since it is usually as thin as 0.01 to 1 μm and an effect of shielding impurities cannot be expected, the resin protective layer 36 needs to have the above characteristics.

  The substrate 32 constituting the color filter 31 has flexibility such as a transparent rigid material such as quartz glass, pyrex glass, or synthetic quartz plate, or a transparent resin film, an optical resin plate, or the like. A transparent flexible material can be used. Among them, Corning 7059 glass is a material having a small coefficient of thermal expansion, excellent dimensional stability and workability in high-temperature heat treatment, and is an alkali-free glass containing no alkali component in the active matrix. Suitable for color filters for color liquid crystal display devices.

The black matrix 34 constituting the color filter 31 is formed by forming a metal thin film such as chromium having a thickness of about 1000 to 2000 mm by a sputtering method, a vacuum vapor deposition method or the like, and patterning this thin film, and shielding light such as carbon fine particles. Forming a resin layer made of polyimide resin, acrylic resin, epoxy resin or the like containing particles and patterning the resin layer, photosensitive resin containing light-shielding particles such as carbon fine particles or metal oxides It may be any one formed by forming a layer and patterning the photosensitive resin layer.
In the present invention, the color filter 31 may not include the black matrix 34.

  Further, the colored layer 35 may be formed by a pigment dispersion method using a photosensitive resin containing a desired colorant, in which a red pattern 35R, a green pattern 35G, and a blue pattern 35B are arranged in a desired pattern shape. Further, it can be formed by a known method such as a printing method, an electrodeposition method, or a transfer method. In addition, for example, by increasing the thickness of the colored layer 35 in the order of the red pattern 35R, the green pattern 35G, and the blue pattern 35B, an optimal liquid crystal layer thickness may be set for each color of the colored layer 35. .

  In the present invention, as described above, the voltage holding of the liquid crystal in which the resin protective layer 36 and the resin columnar protrusion 37 which are the resin members closest to or in contact with the liquid crystal are subjected to the impurity extraction process is performed. It is essential that the rate is 80% or more and the residual DC (ΔE) is 0.5 V or less. Therefore, the colored layer 35 that is not closest to the liquid crystal and not in contact with the liquid crystal does not need to satisfy the above essential requirements, and can be formed by a known method as described above. However, the present invention excludes that the colored layer 35 is such that the voltage holding ratio of the liquid crystal subjected to the impurity extraction treatment is 80% or more and the residual DC (ΔE) is 0.5 V or less. Not what you want. In order to impart the above-described characteristics (the voltage holding ratio of the liquid crystal subjected to the impurity extraction treatment to 80% or more and the residual DC (ΔE) to 0.5 V or less) to the colored layer 35 in this way, an acrylic copolymer Etc. can be used.

  The resin protective layer 36 is provided to flatten the surface of the color filter 31 and to prevent the components contained in the colored layer 35 from eluting into the liquid crystal layer. The color filter 31 is a liquid crystal display device. When used, the black matrix 34 and the colored layer 35 are formed so as to cover at least the liquid crystal layer. In order to make this resin protective layer 36 have the above-mentioned characteristics (the voltage holding ratio of the liquid crystal subjected to the impurity extraction treatment is 80% or more and the residual DC (ΔE) is 0.5 V or less), acrylic resin is used. It can be formed using a resin material such as a polymer. The thickness of the resin protective layer 36 can be set in consideration of the light transmittance of the material used, the surface state of the color filter 31, and the like, and can be set, for example, in the range of 0.1 to 3.0 μm. .

  The resin columnar convex portion 37 constituting the color filter 31 functions as a spacer when the color filter 31 is bonded to the counter electrode substrate. This resin columnar convex part 37 can be formed by, for example, applying a photosensitive resin paint, exposing, developing, and curing in a predetermined pattern. The resin columnar convex portion 37 has a certain height so as to protrude in the range of about 2 to 10 μm from the resin protective layer 36, and the protruding amount is a thickness required for the liquid crystal layer of the liquid crystal display device. It can set suitably from the above. Further, the formation density of the resin columnar protrusions 37 can be appropriately set in consideration of the thickness unevenness of the liquid crystal layer, the aperture ratio, the shape, material, and the like of the columnar protrusions 37. For example, the colored layer 35 is formed. Necessary and sufficient spacer functions are expressed at a ratio of one for each of the red pattern 35R, the green pattern 35G, and the blue pattern 35B. The shape of the resin columnar convex portion 37 is not particularly limited, and may be a columnar shape, a prismatic shape, a truncated cone shape, or the like.

In order to make such a resin columnar protrusion 37 have the above-described characteristics (the voltage holding ratio of the liquid crystal subjected to the impurity extraction treatment is 80% or more and the residual DC (ΔE) is 0.5 V or less). It can be formed using a resin material such as an acrylic copolymer.
In the above-described embodiment, the colored layer 35 including a plurality of colors is provided so as to cover the black matrix 34, but the colored layer 35 may be provided in a non-formation portion of the black matrix 34.

[Liquid Crystal Display]
Next, the liquid crystal display device of the present invention will be described.
FIG. 3 is a schematic sectional view showing an embodiment of the liquid crystal display device of the present invention. In FIG. 3, the liquid crystal display device 101 has the color filter 31 and the counter electrode substrate 111 facing each other at a predetermined interval, the periphery is sealed with a seal member (not shown), and the liquid crystal layer 105 is formed in the gap portion. It has been done. Although not shown, polarizing plates are disposed outside the color filter 31 and the counter electrode substrate 111, respectively.

  The color filter 31 constituting the liquid crystal display device 101 of the present invention is the above-described color filter 31 of the present invention. Therefore, the resin protective layer 36 and the resin columnar protrusion 37 constituting the color filter 31 have the above-described characteristics (the voltage holding ratio of the liquid crystal subjected to the impurity extraction process is 80% or more, and the residual DC (ΔE) is 0. 5V or less). In addition, a common transparent electrode layer 106 for driving liquid crystal and an alignment layer 107 are formed on the resin protective layer 36 of the color filter 31.

  On the other hand, the counter electrode substrate 111 constituting the liquid crystal display device 101 of the present invention includes a transparent pixel electrode 113 and a thin film transistor (TFT) 114 for driving a liquid crystal on a transparent substrate 112, and an alignment layer so as to cover the transparent pixel electrode 113. 115 is formed. The counter electrode substrate 111 includes a gate line group (not shown) for opening and closing a thin film transistor (TFT) 114, a signal line group (not shown) for supplying a video signal, and a common transparent electrode layer on the color filter 31 side. A voltage supply line (not shown) to 106 is provided. These lead wires are usually made of a metal such as aluminum formed in a lump in the manufacturing process of the thin film transistor (TFT) 114.

  As the transparent substrate 112 constituting the counter electrode substrate 111, those described as the color filter substrate 32 can be used.

  The common transparent electrode layer 106 and the transparent pixel electrode layer 113 constituting the liquid crystal display device 101 are made of indium tin oxide (ITO), zinc oxide (ZnO), tin oxide (SnO), or an alloy thereof. The film is formed by a general film formation method such as sputtering, vacuum deposition, or CVD. The thickness of such an electrode layer is about 0.01 to 1 μm, and the effect of blocking the migration of impurities generated from a member located outside the electrode layer to the liquid crystal layer 105 cannot be expected.

  Furthermore, the alignment layers 107 and 115 constituting the liquid crystal display device 101 can be formed of an organic compound such as polyimide, polyamide, polyurethane, and polyurea, and the thickness is about 0.01 to 1 μm. Can do. Such alignment layers 107 and 115 are coated by various printing methods and known coating methods, and then fired and then subjected to alignment treatment (rubbing). Incidentally, since the alignment layers 107 and 115 made of such an organic compound have a very small thickness, it is not necessary to consider the mixing of impurities into the liquid crystal layer 105 which causes display defects. Such alignment layers 107 and 115 can hardly be expected to shield the migration of impurities generated from the members located outside of the alignment layers 107 to the liquid crystal layer 105.

  The liquid crystal layer 105 constituting the liquid crystal display device 101 has a voltage holding ratio of 95% or more measured under the above voltage holding ratio measurement conditions in the state before the impurity extraction process, and It can be formed using a liquid crystal having a residual DC (ΔE) measured under a residual DC (ΔE) measurement condition of 0.05 V or less.

  In such a liquid crystal display device 101 of the present invention, the thickness of the liquid crystal layer 105 is set by the resin columnar convex portion 37, and the liquid crystal layer 105 is directly in contact with the liquid crystal layer 105 or through a thin film such as an alignment layer or a transparent electrode. The resin members located closest to the liquid crystal layer 105 are only the resin protective layer 36 and the resin columnar protrusions 37 constituting the color filter 31. As described above, the resin protective layer 36 and the resin columnar convex portion 37 set the voltage holding ratio of the liquid crystal subjected to the impurity extraction treatment to 80% or more, preferably 90% or more, more preferably 95% or more. And the residual DC (ΔE) is 0.5 V or less, preferably 0.2 V or less, more preferably 0.1 V or less. Accordingly, the liquid crystal display device 101 is excellent in display quality by preventing occurrence of display defects such as image sticking and white unevenness even under severe display conditions such as long-time display and high temperature and high humidity. .

  FIG. 4 is a schematic cross-sectional view showing another embodiment of the liquid crystal display device of the present invention. In FIG. 4, a liquid crystal display device 201 has a color filter 31 ′ and a counter electrode substrate 211 facing each other at a predetermined interval, a peripheral portion is sealed with a seal member (not shown), and a liquid crystal layer 205 is formed in the gap portion. It is formed. Although not shown, polarizing plates are provided outside the color filter 31 ′ and the counter electrode substrate 211, respectively.

  The color filter 31 ′ constituting the liquid crystal display device 201 of the present invention is the same as the color filter 31 of the present invention described above except that the black matrix 34 is not provided, and each member is denoted by the same member number. is there. Therefore, the resin protective layer 36 and the resin columnar protrusion 37 constituting the color filter 31 ′ have the above-described characteristics (the voltage holding ratio of the liquid crystal subjected to the impurity extraction process is 80% or more and the residual DC (ΔE) is 0. .5V or less). Further, a common transparent electrode layer 206 for driving liquid crystal and an alignment layer 207 are formed on the resin protective layer 36 of the color filter 31 ′.

  On the other hand, the counter electrode substrate 211 constituting the liquid crystal display device 201 of the present invention is formed on the semiconductor driving element 220, the transparent pixel electrode 213, and the semiconductor driving element 220 integrally formed on the transparent substrate 212. A resin light shielding layer 215 and an alignment layer 216 formed to cover the transparent pixel electrode 213, the semiconductor driving element 220, and the resin light shielding layer 215 are provided.

  The semiconductor driving element 220 is a thin film transistor (TFT) including a gate electrode 221, a gate insulating film 222, a semiconductor layer 223 such as amorphous silicon, a source electrode 224, and a drain electrode 225. The drain electrode 225 has one end connected to the semiconductor layer 223 and the other end connected to the transparent pixel electrode 213.

  The resin light shielding layer 215 is formed on the source electrode 224 and the drain electrode 225 so as to shield the semiconductor layer 223, and functions to suppress the light leakage current of the semiconductor driving element 220. The resin light-shielding layer 215 is a resin member that is in contact with the liquid crystal layer 205 via the alignment layer 216 in the liquid crystal display device 201. In the present invention, the resin light-shielding layer 215 is made of liquid crystal that has been subjected to impurity extraction processing. The voltage holding ratio is 80% or more, preferably 90% or more, more preferably 95% or more, and the residual DC (ΔE) is 0.5 V or less, preferably 0.2 V or less, more preferably 0. .1V or less.

Such a resin light-shielding layer 215 is formed by forming a photosensitive resin layer containing insulating light-shielding particles such as Cu—Fe—Mn composite oxide, and patterning the photosensitive resin layer. Any of these may be used.
As the transparent substrate 212 constituting the counter electrode substrate 211, those described as the color filter substrate 32 can be used.

  The common transparent electrode layer 206 and the transparent pixel electrode 213 constituting the liquid crystal display device 201 are made of indium tin oxide (ITO), zinc oxide (ZnO), tin oxide (SnO), or an alloy thereof. The film is formed by a general film forming method such as sputtering, vacuum deposition, or CVD. The thickness of such an electrode layer is about 0.01 to 1 μm, and an effect of shielding impurities can hardly be expected.

  Furthermore, the alignment layers 207 and 216 constituting the liquid crystal display device 201 can be formed of an organic compound such as polyimide, polyamide, polyurethane, or polyurea, and the thickness is about 0.01 to 1 μm. Can do. Such alignment layers 207 and 216 are coated by various printing methods and known coating methods, and then fired and then subjected to alignment treatment (rubbing). Since the alignment layers 207 and 216 made of such an organic compound have a very small thickness, it is not necessary to consider the mixing of impurities into the liquid crystal layer 205 that causes display defects. Such alignment layers 207 and 216 can hardly be expected to act to shield impurities.

  The liquid crystal layer 205 constituting the liquid crystal display device 201 has a voltage holding ratio of 95% or more measured under the voltage holding ratio measuring condition as described above in the state before the impurity extraction process, and It can be formed using a liquid crystal having a residual DC (ΔE) measured under a residual DC (ΔE) measurement condition of 0.05 V or less.

  In such a liquid crystal display device 201 of the present invention, the thickness of the liquid crystal layer 205 is set by the resin columnar convex portion 37, and the liquid crystal layer 205 is directly in contact with the liquid crystal layer 205 or through a thin film such as an alignment layer or a transparent electrode. The resin members located closest to the liquid crystal layer 205 are only the resin protective layer 36, the resin columnar protrusion 37, and the resin light-shielding layer 215 of the counter electrode substrate 211 that constitute the color filter 31 ′. The resin protective layer 36, the resin columnar convex portion 37, and the resin light shielding layer 215 have a voltage holding ratio of the liquid crystal subjected to the impurity extraction treatment of 80% or more, preferably 90% or more, more preferably as described above. The residual DC (ΔE) is 0.5 V or less, preferably 0.2 V or less, more preferably 0.1 V or less. Thereby, the liquid crystal display device 201 is excellent in display quality by preventing occurrence of display defects such as image sticking and white unevenness even under severe display conditions such as long-time display and high temperature and high humidity. .

  FIG. 5 is a schematic cross-sectional view showing another embodiment of the liquid crystal display device of the present invention. In FIG. 5, a liquid crystal display device 501 is a reflective liquid crystal display device, in which a color filter 31 ″ and a counter electrode substrate 511 are opposed to each other at a predetermined interval, and a peripheral portion is sealed with a seal member (not shown). A liquid crystal layer 505 is formed in the gap portion, although not shown, a retardation plate and a polarizing plate are disposed outside the counter electrode substrate 511 on the viewer side.

  The color filter 31 ″ constituting the liquid crystal display device 501 of the present invention is provided with the reflective layer 38 between the substrate 32, the black matrix 34, and the colored layer 35, and the color filter 31 of the present invention described above. Each member is indicated by the same member number. Therefore, the resin protective layer 36 and the resin columnar convex portion 37 constituting the color filter 31 ″ have the above-described characteristics (liquid crystal subjected to impurity extraction processing). Voltage holding ratio of 80% or more and residual DC (ΔE) of 0.5 V or less).

The reflective layer 38 constituting the color filter 31 ″ can be formed by forming a metal thin film such as aluminum by a known film forming means such as a vapor deposition method or a sputtering method.
A common transparent electrode layer 506 for driving liquid crystal and an alignment layer 507 are formed on the resin protective layer 36 of the color filter 31 ″.

  On the other hand, a counter electrode substrate 511 constituting the liquid crystal display device 501 of the present invention includes a transparent pixel electrode 513 and a thin film transistor (TFT) 514 for driving liquid crystal on a transparent substrate 512, and an alignment layer covering the transparent pixel electrode 513. 515 is formed. The counter electrode substrate 511 includes a gate line group (not shown) for opening and closing a thin film transistor (TFT) 514, a signal line group (not shown) for supplying a video signal, and a common transparent electrode on the color filter 31 ″ side. A voltage supply line (not shown) is provided to the layer 506. These lead wires are usually made of a metal such as aluminum formed in a lump in the manufacturing process of the thin film transistor (TFT) 514. is there.

As the transparent substrate 512 that constitutes the counter electrode substrate 511, those described as the color filter substrate 32 can be used.
The common transparent electrode layer 506 and the transparent pixel electrode layer 513 constituting the liquid crystal display device 501 are made of indium tin oxide (ITO), zinc oxide (ZnO), tin oxide (SnO), or an alloy thereof. The film is formed by a general film formation method such as sputtering, vacuum deposition, or CVD. The thickness of such an electrode layer is about 0.01 to 1 μm, and an effect of shielding impurities can hardly be expected.

  Furthermore, the alignment layers 507 and 515 constituting the liquid crystal display device 501 can be formed of an organic compound such as polyimide, polyamide, polyurethane, or polyurea, and the thickness is about 0.01 to 1 μm. Can do. Such alignment layers 507 and 515 are coated by various printing methods and known coating methods, and then fired and then subjected to alignment treatment (rubbing). Since the alignment layers 507 and 515 made of such an organic compound are extremely small in thickness, it is not necessary to consider the mixing of impurities into the liquid crystal layer 505 that cause display defects. Such alignment layers 507 and 515 can hardly be expected to act to shield impurities.

  The liquid crystal layer 505 constituting the liquid crystal display device 501 has a voltage holding ratio of 95% or more measured under the voltage holding ratio measuring condition as described above in the state before the impurity extraction process described above, and as described above. It can be formed using a liquid crystal having a residual DC (ΔE) measured under a residual DC (ΔE) measurement condition of 0.05 V or less.

In the liquid crystal display device 501 of the present invention as described above, the thickness of the liquid crystal layer 505 is set by the resin columnar convex portion 37, and the liquid crystal layer 505 is in direct contact with the liquid crystal layer 505 or through a thin film such as an alignment layer or a transparent electrode. The resin member located closest to the liquid crystal layer 505 is only the resin protective layer 36 and the resin columnar convex portion 37 constituting the color filter 31 ″. The resin protective layer 36 and the resin columnar convex portion 37 are As described above, the voltage holding ratio of the liquid crystal subjected to the impurity extraction treatment is 80% or more, preferably 90% or more, more preferably 95% or more, and the residual DC (ΔE) is 0.5 V. In the following, it is preferably 0.2 V or less, more preferably 0.1 V or less, so that the liquid crystal display device 501 can display images even under severe display conditions such as long-time display and high temperature and high humidity. With Viewing failure such as uneven whiteness is prevented, is excellent in display quality.
The embodiments of the color filter and the liquid crystal display device described above are examples, and the present invention is not limited to these.

Next, an Example is shown and this invention is demonstrated further in detail.
Impurity extraction treatment test Preparation of sample In order to use for the impurity extraction process, a coating film was formed on a glass substrate (Corning 7059 glass) using various materials used for a color liquid crystal display device as follows.
(1) Photosensitive paint for black matrix and photosensitive paint for colored layer

  Black matrix photosensitive paint and colored layer photosensitive paints R1, G1, G2, and B1 add beads to the dispersion composition (containing pigment, dispersant, and solvent) and disperse with a disperser for 3 hours. Then, the dispersion from which the beads have been removed and the clear resist composition (polymer, monomer, additive, disclosure agent and solvent) are mixed, and the composition is shown below. A paint shaker was used as the disperser.

Next, the prepared black matrix photosensitive paint and colored layer photosensitive paints R1, G1, G2, and B1 were each applied to a glass substrate to a thickness of 1.5 μm by spin coating, 90 ° C., Pre-baked under conditions of 3 minutes, whole surface exposure (500 mJ / cm ² ), spray development using 0.05% KOH aqueous solution for 60 seconds, and then post-baked at 200 ° C. for 30 minutes, glass with a coating film A substrate was produced.
(Photosensitive paint for black matrix)
Black pigment: 14.0 parts by weight (TM Black # 95550 manufactured by Dainichi Seika Kogyo Co., Ltd.)
-Dispersant (Disperbyk 111 manufactured by Big Chemie Co., Ltd.) ... 1.2 parts by weight-Polymer (VR60 manufactured by Showa Polymer Co., Ltd.) ... 2.8 parts by weight-Monomer (SR399 manufactured by Sartomer Co., Ltd.) ... 3.5 weights Parts ・ Additive (L-20, manufactured by Soken Chemical Co., Ltd.) 0.7 parts by weight Initiator 1.6 parts by weight (2-benzyl-2-dimethylamino-1- (4-morpholino)
Phenyl) -butanone-1)
・ Initiator: 0.3 part by weight (4,4′-diethylaminobenzophenone)
Initiator (2,4-diethylthioxanthone) 0.1 part by weight Solvent (ethylene glycol monobutyl ether) 75.8 parts by weight

(Photosensitive paint R1 for red pattern)
・ Red pigment: 4.8 parts by weight (Chromotal Red A2B manufactured by Ciba Geigy)
・ Yellow pigment: 1.2 parts by weight (PASFOL Yellow D1819 manufactured by BASF)
Dispersant (Solsperse 24000 manufactured by Zeneca Corporation) 3.0 parts by weight Monomer (SR399 manufactured by Sartomer Co.) 4.0 parts by weight Polymer 1 5.0 parts by weight Initiator (manufactured by Ciba Geigy) Irgacure 907) 1.4 parts by weight Initiator 0.6 parts by weight (2,2'-bis (o-chlorophenyl) -4,5,4 ', 5'-
Tetraphenyl-1,2'-biimidazole)
・ Solvent: 80.0 parts by weight (propylene glycol monomethyl ether acetate)

(Photosensitive paint G1 for green pattern)
Green pigment: 4.2 parts by weight (Monestral Green 9Y-C manufactured by Zeneca)
・ Yellow pigment: 1.8 parts by weight (PASFOL Yellow D1819 manufactured by BASF)
Dispersant (Solsperse 24000 manufactured by Zeneca Corporation) 3.0 parts by weight Monomer (SR399 manufactured by Sartomer Co.) 4.0 parts by weight Polymer 1 5.0 parts by weight Initiator (manufactured by Ciba Geigy) Irgacure 907) 1.4 parts by weight Initiator 0.6 parts by weight (2,2'-bis (o-chlorophenyl) -4,5,4 ', 5'-
Tetraphenyl-1,2'-biimidazole)
・ Solvent: 80.0 parts by weight (propylene glycol monomethyl ether acetate)

(Photosensitive paint G2 for green pattern)
Green pigment: 4.2 parts by weight (Zeneca Co., Ltd. Monastral Green 6Y-CL)
・ Yellow pigment: 1.8 parts by weight (PASFOL Yellow D1819 manufactured by BASF)
Dispersant (Solsperse 24000 manufactured by Zeneca Corporation) 3.0 parts by weight Monomer (SR399 manufactured by Sartomer Co.) 4.0 parts by weight Polymer 1 5.0 parts by weight Initiator (manufactured by Ciba Geigy) Irgacure 907) 1.4 parts by weight Initiator 0.6 parts by weight (2,2'-bis (o-chlorophenyl) -4,5,4 ', 5'-
Tetraphenyl-1,2'-biimidazole)
・ Solvent: 80.0 parts by weight (propylene glycol monomethyl ether acetate)

(Photosensitive paint B1 for blue pattern)
・ Blue pigment: 6.0 parts by weight (BASF Heliogen Blue L6700F)
-Pigment derivative: 0.6 parts by weight (Solsperse 12000 manufactured by Zeneca)
・ Dispersant (Solsperse 24000 manufactured by Zeneca Corporation) 2.4 parts by weight Monomer (SR399 manufactured by Sartomer Co., Ltd.) 4.0 parts by weight Polymer 1 5.0 parts by weight Initiator (manufactured by Ciba Geigy) Irgacure 907) 1.4 parts by weight Initiator 0.6 parts by weight (2,2'-bis (o-chlorophenyl) -4,5,4 ', 5'-
Tetraphenyl-1,2'-biimidazole)
・ Solvent: 80.0 parts by weight (propylene glycol monomethyl ether acetate)

  The polymer 1 is based on 100 mol% of a copolymer of benzyl methacrylate: styrene: acrylic acid: 2-hydroxyethyl methacrylate = 15.6: 37.0: 30.5: 16.9 (molar ratio). 2-methacryloyloxyethyl isocyanate was added at 16.9 mol%, and the weight average molecular weight was 42500. The same applies to the polymer 1 used in the following other paints.

(2) Coating for protective layer A coating for protective layer having the following composition was prepared, and a glass substrate with a coating film was prepared in the same manner as described above.
(Protective layer paint)
・ Monomer (SR399 manufactured by Sartomer Co., Ltd.) 7.1 parts by weight Polymer 1 8.8 parts by weight Epoxy resin 9.7 parts by weight (Epicoat 180S70 manufactured by Yuka Shell Epoxy Co., Ltd.)
Initiator (Irgacure 907 manufactured by Ciba Geigy Co., Ltd.) ... 1.4 parts by weight Initiator ... 1.0 part by weight (2,2'-bis (o-chlorophenyl) -4,5,4 ', 5'-
Tetraphenyl-1,2'-biimidazole)
・ Solvent (dimethyldiglycol): 38.0 parts by weight ・ Solvent (3-methoxybutyl acetate): 34.0 parts by weight

(3) Photosensitive paint for columnar projections Two types of photosensitive coatings S1 and S2 for columnar projections having the following compositions were prepared. Next, the prepared photosensitive coatings for columnar protrusions are applied onto a glass substrate by a spin coating method, prebaked at 100 ° C. for 3 minutes, exposed to the whole surface, and spray-developed using a 0.01% KOH aqueous solution. Then, a glass substrate with a coating film was produced by post-baking at 200 ° C. for 30 minutes.
(Photosensitive paint S1 for columnar protrusions)
Monomer (SR399 manufactured by Sartomer Co., Ltd.) 8.7 parts by weight Polymer 1 10.9 parts by weight Epoxy resin 12.1 parts by weight (Epicoat 180S70 manufactured by Yuka Shell Epoxy Co., Ltd.)
-Surfactant: 1.0 part by weight (Nippon Yuka nonionic HS-210)
・ Initiator (Irgacure 369 manufactured by Ciba Geigy Co., Ltd.) 1.2 parts by weight Initiator 1.0 part by weight (2,2′-bis (o-chlorophenyl) -4,5,4 ′, 5′-
Tetraphenyl-1,2'-biimidazole)
・ Solvent: 29.1 parts by weight (propylene glycol monomethyl ether acetate)
・ Solvent (Acetic acid-3-methyoxybutyl) 36.0 parts by weight

(Photosensitive paint S2 for columnar protrusions)
Monomer (SR399 manufactured by Sartomer Co., Ltd.) 8.7 parts by weight Polymer 1 10.9 parts by weight Epoxy resin 12.1 parts by weight (Epicoat 180S70 manufactured by Yuka Shell Epoxy Co., Ltd.)
・ Surfactant ... 2.0 parts by weight (Nippon Yuka nonionic HS-210)
・ Initiator (Irgacure 369 manufactured by Ciba Geigy Co., Ltd.) 1.2 parts by weight Initiator 1.0 part by weight (2,2′-bis (o-chlorophenyl) -4,5,4 ′, 5′-
Tetraphenyl-1,2'-biimidazole)
・ Solvent: 28.1 parts by weight (propylene glycol monomethyl ether acetate)
・ Solvent (Acetic acid-3-methyoxybutyl) 36.0 parts by weight

B. Impurity extraction treatment and measurement of voltage holding ratio / residual DC (ΔE) For the various glass substrates with a coating film produced in step 1, the impurity extraction treatment for liquid crystal (MLC-6846-000 manufactured by Merck Japan Co., Ltd.) is performed by the following method, and then the voltage holding ratio and residual DC (ΔE) of this liquid crystal are determined. The measurement was performed under the following measurement conditions, and the results are shown in Table 1 below.

The liquid crystal used had a voltage holding ratio of 98% or more measured under the following voltage holding ratio measurement conditions in the state before the impurity extraction treatment, and the residual DC (ΔE) measured under the following residual DC (ΔE) measuring conditions. ) Was 0.01 V or less.
(Impurity extraction method)
A glass substrate with a coating having a surface area of 4 cm ² is immersed in a liquid crystal having a capacity of 0.2 ml, and extraction is carried out by holding at 105 ° C. for 5 hours.

(Voltage holding ratio measurement conditions)
As a layer structure, a measurement cell consisting of substrate / electrode / alignment layer / liquid crystal / alignment layer / electrode / substrate is prepared, and liquid crystal subjected to impurity extraction treatment is injected and measured under the following conditions.
・ Distance between electrodes: 5 to 15 μm
・ Applied voltage pulse amplitude: 5V
・ Applied voltage pulse frequency: 60 Hz
・ Applied voltage pulse width: 16.67 msec

(Residual DC (ΔE) measurement conditions)
As a layer structure, a measurement cell comprising a substrate / electrode / alignment layer / liquid crystal / alignment layer / electrode / substrate is prepared, and liquid crystal subjected to impurity extraction treatment is injected, and residual DC (ΔE) ( In the voltage-capacitance hysteresis loop,
From the maximum capacitance (Cs) and the minimum capacitance (C0), the formula (C0 + Cs) /
Measure the voltage shift amount (indicated by the arrow in FIG. 2) in the capacitance specified in 2.
・ Distance between electrodes: 5 to 15 μm
Liquid crystal used: Capacitance saturation voltage (Vs ′ in FIG. 2) is 10V
・ Voltage-capacitance hysteresis loop measurement voltage range: -10V to + 10V

Production of color filter (1) Color filter sample 1
As a substrate for a color filter, a glass substrate (Corning 7059 glass) having a size of 100 mm × 100 mm and a thickness of 0.7 mm was prepared. After this substrate was washed according to a conventional method, a black matrix photosensitive paint having the above composition was applied to the entire surface of one side of the substrate, and mask exposure, development, and post-baking were performed to form a black matrix (thickness: 1.5 μm).

  Next, a colored layer was formed using the three types of photosensitive paints R1, G1, and B1 for the colored layer having the above composition. That is, a red pattern photosensitive paint R1 was applied to the entire surface of the substrate on which the black matrix was formed by spin coating to form a red photosensitive resin layer, and prebaked (90 ° C., 3 minutes). . Thereafter, the red photosensitive resin layer is alignment-exposed using a photomask for a predetermined colored pattern, developed with a developer (0.05% KOH aqueous solution), and then post-baked (200 ° C., 30 minutes). Then, a red pattern (thickness: 1.5 μm) was formed at a predetermined position with respect to the black matrix pattern.

Similarly, a green pattern (thickness of 1.5 μm) was formed at a predetermined position with respect to the black matrix pattern using the photosensitive paint G1 for the green pattern. Further, a blue pattern (thickness: 1.5 μm) was formed at a predetermined position with respect to the black matrix pattern by using the photosensitive paint B1 for the blue pattern.
As a result, a color filter (sample 1) having a structure as shown in FIG. 1 was obtained.

(2) Color filter sample 2
A color filter (Sample 2) was produced in the same manner as Sample 1 except that three types of photosensitive paints R1, G2, and B1 having the above compositions were used as the photosensitive paint for the colored layer.

(3) Color filter sample 3
The protective layer paint having the above composition is applied by spin coating so as to cover the black matrix and the colored layer of the color filter (sample 2), and dried to form a protective layer having a thickness of 1.5 μm. A color filter (sample 3) having a structure as shown in FIG. 4 was obtained.

(4) Color filter sample 4
The columnar convex photosensitive paint S1 having the above composition was applied by spin coating so as to cover the protective layer of the color filter (sample 3), and prebaked (100 ° C., 3 minutes). Thereafter, exposure is performed using a predetermined columnar convex photomask, development is performed with a developer (0.01% KOH aqueous solution), and then post-baking (200 ° C., 30 minutes) is performed, and the height is 5 μm. A plurality of columnar protrusions were formed to obtain a color filter (sample 4) having a structure as shown in FIG.

(5) Color filter sample 5
A color filter (Sample 5) was prepared in the same manner as Sample 4 except that the photosensitive coating S2 having the above composition was used as the photosensitive coating for columnar convex portions.

Production of Liquid Crystal Display Device A transparent common electrode made of indium tin oxide (ITO) was formed on each of the color filters (samples 1 to 5).
Further, a glass substrate (Corning 7059 glass) having a size of 100 mm × 100 mm and a thickness of 0.7 mm was prepared as a transparent substrate. After this substrate is cleaned according to a standard method, thin film transistors (TFTs) are formed at a plurality of predetermined locations on the substrate, and transparent pixel electrodes are formed of indium tin oxide (ITO) so as to be connected to the drain electrodes of each TFT. Thus, a counter electrode substrate was produced.

Next, a polyimide resin coating was applied and dried to cover the transparent common electrode of the color filter and the transparent pixel electrode of the counter electrode substrate, and an alignment layer (thickness 0.07 μm) was provided to perform alignment treatment.
Next, liquid crystal display devices (Samples 1 to 5) were produced using these color filters and the counter electrode substrate. In addition, Merck Japan MLC-6846-000 was used as liquid crystal.

Evaluation of liquid crystal display devices For the five types of liquid crystal display devices (samples 1 to 5) produced, image display was continuously performed for 72 hours under the conditions of 23 ° C. and 60% RH, and the display quality was evaluated according to the following criteria. The results are shown in Table 2 below.
(Evaluation criteria for display quality)
○: Display quality is extremely good without image sticking and white unevenness ×: Image sticking and white unevenness are observed, and a display defect phenomenon is observed.

As shown in Table 2, each of the liquid crystal display devices of Samples 1, 3, and 4 has a liquid crystal layer in a position where each of the constituting color filters is in direct contact with the liquid crystal layer or through an alignment layer or a transparent electrode Is the color filter of the present invention that maintains the voltage holding ratio of the liquid crystal subjected to the impurity extraction treatment at 80% or more and the residual DC (ΔE) at 0.5 V or less. Even when the display is performed for a long time under high humidity, the display failure phenomenon does not occur.
On the other hand, in the liquid crystal display device of sample 2, the green pattern of the colored layer having a voltage holding ratio of less than 80% and a residual DC (ΔE) exceeding 0.5 V is in direct contact with the liquid crystal layer. In a liquid crystal display device, columnar protrusions having a voltage holding ratio of less than 80% and a residual DC (ΔE) of more than 0.5 V are in direct contact with the liquid crystal layer, so both image sticking and white unevenness are observed, resulting in a display failure phenomenon. Was recognized.

Industrial use of the invention

  This is useful in the production of color filters used in liquid crystal display devices and in the production of liquid crystal display devices.

It is a schematic sectional drawing which shows an example of embodiment of the color filter of this invention. It is a figure which shows the voltage-capacitance hysteresis loop for demonstrating residual DC ((DELTA) E). It is a schematic sectional drawing which shows one Embodiment of the liquid crystal display device of this invention. It is a schematic sectional drawing which shows other embodiment of the liquid crystal display device of this invention. It is a schematic sectional drawing which shows other embodiment of the liquid crystal display device of this invention.

Explanation of symbols

31, 31 ', 31 "... Color filter 32 ... Substrate 34 ... Black matrix 35 ... Colored film 36 ... Resin protective layer 37 ... Resin columnar protrusion 101, 201, 501 ... Liquid crystal display device 105, 205, 505 ... Liquid crystal layer 111 , 211, 511 ... counter electrode substrate 114, 220, 514 ... semiconductor drive element (thin film transistor)
215: Resin light shielding layer 106, 206, 506 ... Common transparent electrode 113, 213, 513 ... Transparent pixel electrode

Claims (4)

A substrate, a colored layer composed of a plurality of colors formed in a predetermined pattern on the substrate, a transparent resin protective layer formed so as to cover at least the colored layer, and the resin protection formed at a plurality of predetermined sites in the manufacturing method of the color filter to be a transparent resin pillar-shaped convex portion protruding than layer,
A liquid crystal having a voltage holding ratio of 95% or more and a residual DC (ΔE) of 0.05 V or less is prepared, and as a resin member, the voltage of the liquid crystal after being subjected to impurity extraction treatment by being immersed in the liquid crystal A resin member having a retention rate of 80% or more and a residual DC (ΔE) of 0.5 V or less is selected, and the resin protective layer and the resin columnar protrusion are formed using the resin member. The manufacturing method of the color filter characterized by this. The method for producing a color filter according to claim 1, wherein a common transparent electrode layer is formed on the resin protective layer. In a manufacturing method of a liquid crystal display device comprising a color filter and a counter electrode substrate facing each other so as to provide a gap portion via a seal member, and a liquid crystal layer sealed in the gap portion,
A method for manufacturing a liquid crystal display device , wherein the color filter uses a color filter manufactured by the method for manufacturing a color filter according to claim 1. A color filter and a counter electrode substrate facing each other so as to provide a gap portion through a seal member, and a liquid crystal layer sealed in the gap portion, wherein the counter electrode substrate includes a semiconductor driving element having a resin light shielding layer. In the manufacturing method of the liquid crystal display device provided,
The color filter using a color filter manufactured by the method for producing a color filter according to claim 1 or claim 2,
A liquid crystal having a voltage holding ratio of 95% or more and a residual DC (ΔE) of 0.05 V or less is prepared, and as a resin member, the voltage of the liquid crystal after being subjected to impurity extraction treatment by being immersed in the liquid crystal A liquid crystal display characterized by selecting a resin member having a retention rate of 80% or more and a residual DC (ΔE) of 0.5 V or less, and forming the resin light-shielding layer using the resin member Device manufacturing method .

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