JP2007047203A - Method for manufacturing liquid crystal display element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a liquid crystal display element, with which the liquid crystal display element with excellent display quality is manufactured. <P>SOLUTION: A light shielding section is formed by applying coloring resists with a plurality of colors to a substrate for forming a light shielding section for a plurality of times in superposing, and making coloring pigments of the coloring resists applied at least on and after the second application be adsorbed to a coloring resist layer formed with the first application of the coloring resist. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a liquid crystal display element, and more particularly to a method for manufacturing a liquid crystal display element having a light shielding portion.

  In general, a liquid crystal display element has an array substrate, a counter substrate, a liquid crystal layer sandwiched between the substrates, and a color filter formed on one of the array substrate and the counter substrate. ing. The color filter is composed of colored layers of red, green and blue. Between the array substrate and the counter substrate, for example, plastic beads having a uniform particle diameter are arranged as spacers, and the gap between the two substrates is kept constant. The array substrate and the counter substrate are joined by a sealing material disposed on the peripheral edge of both substrates. As a display method of the liquid crystal display element, for example, a TN (twisted nematic) display method, an STN (super twisted nematic) display method, a GH (guest-host) display method, or an ECB (electric field control birefringence) display method. And a method using a ferroelectric liquid crystal.

  In a color display type active matrix driving liquid crystal display element, a plurality of signal lines and a plurality of scanning lines are arranged in a matrix on an array substrate, and amorphous silicon (for example, near each intersection of these signal lines and scanning lines) A thin film transistor (hereinafter referred to as TFT) using a-Si) as a channel layer is provided. A plurality of auxiliary capacitance lines are disposed on the array substrate and extend in parallel with the scanning lines. Each auxiliary capacitance line is opposed to the auxiliary capacitance electrode via an insulating film, and the auxiliary capacitance element is configured by the auxiliary capacitance line, the insulating film, and the auxiliary capacitance electrode. Each TFT is connected to a pixel electrode formed on the substrate. An alignment film is formed on the substrate including the pixel electrode.

  In the counter substrate, a color filter, a counter electrode, and an alignment film are sequentially formed on the substrate. An electrode transition material for applying a voltage from the array substrate to the counter substrate is provided at the peripheral portions of the array substrate and the counter substrate. The electrode transition material is made of a conductive material such as silver paste, and electrically connects the array substrate and the counter substrate. A liquid crystal layer is formed between the array substrate and the counter substrate, and polarizing plates are respectively disposed on the outer surfaces of these substrates to constitute a liquid crystal display element (see, for example, Patent Document 1). Such a liquid crystal display element has a plurality of pixels, and each pixel includes a TFT and a pixel electrode.

Recently, in addition to the liquid crystal display element provided with the color filter on the counter substrate as described above, various liquid crystal display elements provided with the color filter on the array substrate have been developed, and the COA for forming the color filter on the array substrate is provided. A liquid crystal display element has been developed that achieves a high aperture ratio by adopting a (color filter on array) structure, and thus a high transmittance. In addition, a liquid crystal display element or the like has been developed in which a columnar spacer is formed on at least one of an array substrate and a counter substrate by photolithography to maintain a uniform inter-substrate distance. When the liquid crystal display element has a COA structure, a light shielding portion is formed at the peripheral edge of the color filter on the array substrate. The light shielding portion is formed by processing a black resist by a photolithography method.
Japanese Patent Laid-Open No. 11-258635

  In the above-described liquid crystal display element, since a high-speed response is recently required, a narrow cell gap is made to reduce a gap (cell gap) between the array substrate and the counter substrate, and the columnar spacer is formed low. . By forming the columnar spacers low by a photolithography method, the processability can be improved.

However, when the columnar spacer and the light shielding part are simultaneously formed of the same material, the film thickness of the light shielding part is reduced, and the OD (optical density) value (optical density) of the light shielding part is lowered. For this reason, light leakage occurs in the light shielding portion, and the appearance of the display image is deteriorated.
The present invention has been made in view of the above points, and an object thereof is to provide a method of manufacturing a liquid crystal display element capable of manufacturing a liquid crystal display element excellent in display quality.

  In order to solve the above problems, a method of manufacturing a liquid crystal display element according to an aspect of the present invention includes an array substrate having a plurality of wirings and a plurality of switching elements connected to the plurality of wirings, and a gap between the array substrates. A counter substrate held and opposed to the substrate; a liquid crystal layer sandwiched between the array substrate and the counter substrate; and a light shielding portion formed on one of the array substrate and the light shielding portion forming substrate. In the method for manufacturing a liquid crystal display element provided, a plurality of colored resists are applied to the light-shielding portion forming substrate in a plurality of times and applied to the colored resist layer formed by applying the first colored resist at least a second time or later. The light-shielding portion is formed by adsorbing the color pigment of the color resist applied to the substrate.

  According to the present invention, a method for manufacturing a liquid crystal display element capable of manufacturing a liquid crystal display element excellent in display quality can be provided.

  Hereinafter, a method for manufacturing a liquid crystal display element according to an embodiment of the present invention will be described in detail with reference to the drawings. First, the configuration of the liquid crystal display element manufactured by this manufacturing method will be described.

  As shown in FIG. 12, the liquid crystal display element includes an array substrate 1, a counter substrate 2, a liquid crystal layer 3, a color filter 4, a light shielding part 5, polarizing plates 6 and 7, and retardation plates 8 and 9. And a backlight unit L. In this embodiment, an XGA (eXtended Graphics Array) array substrate 1 will be described as an example.

  The array substrate 1 includes a glass substrate 10 as a transparent insulating substrate. On the glass substrate 10, a plurality of signal lines and a plurality of scanning lines (not shown) are provided in a matrix, and for example, TFTs 11 are provided as switching elements in the vicinity of the intersections between the signal lines and the scanning lines. The TFT 11 includes a gate electrode 12 extending a part of the scanning line, a gate insulating film 13 provided on the gate electrode, a semiconductor film 14 facing the gate electrode through the gate insulating film, and one region of the semiconductor film. And a drain electrode 16 connected to the other region. The source electrode 15 is connected to a signal line, and the drain electrode 16 is connected to a pixel electrode 17 described later.

  On the glass substrate 10 including the TFT 11, the scanning line, and the signal line, the red coloring layer 4R, the green coloring layer 4G, and the blue coloring layer 4B are adjacent to each other and arranged alternately. The colored layers 4R, 4G, and 4B form the color filter 4. The color filter 4 is formed in a rectangular color filter forming region R <b> 1 located at the center of the glass substrate 10. Outside the color filter forming region R1, a rectangular frame-shaped light shielding portion 5 is formed on the glass substrate 10. The light-shielding part 5 is formed in the light-shielding part forming region R2 along the entire periphery of the colored layer peripheral part of the color filter forming region R1. The light shielding portion 5 contributes to shielding light leaking from the color filter forming region R1, that is, the periphery of the image display region.

Although not all shown, a plurality of columnar spacers 31 as spacers are formed on the colored layers 4R, 4G, and 4B at a predetermined density, for example, only on the colored layer 4R. Pixel electrodes 17 are formed on the colored layers 4R, 4G, and 4B, respectively, and arranged in a predetermined pattern. The pixel electrode 17 is electrically connected to the drain electrode 16 of the TFT 11 through a contact hole 4h formed through the colored layers 4R, 4G, and 4B. An alignment film 18 is formed on almost the entire surface of the glass substrate 10 so as to overlap the pixel electrode 17.
The counter substrate 2 includes a glass substrate 20 as a transparent insulating substrate. On the glass substrate 20, a counter electrode 21 and an alignment film 22 are sequentially formed.

  The array substrate 1 and the counter substrate 2 are arranged to face each other with a predetermined gap by a columnar spacer 31. The array substrate 1 and the counter substrate 2 are bonded to each other by a sealing material 32 disposed at the peripheral edge of both substrates. The liquid crystal layer 3 is sandwiched between the array substrate 1 and the counter substrate 2. A liquid crystal injection port (not shown) formed in a part of the sealing material 32 is sealed with a sealing material (not shown). On the outer surface of the array substrate 1, a polarizing plate 6 and a retardation plate 7 are arranged in order. On the outer surface of the counter substrate 2, a polarizing plate 8 and a retardation plate 9 are arranged in order. The outer surface of the phase difference plate 9 is a display surface S for displaying an image.

  The backlight unit L is disposed on the outer surface side of the array substrate 1. The backlight unit L includes a light guide plate La disposed to face the phase difference plate 7, and a light source Lb and a reflection plate Lc disposed to face one side edge of the light guide plate.

Next, an apparatus for manufacturing a liquid crystal display element will be described.
As shown in FIG. 1, the manufacturing apparatus 40 includes a hot plate 41 for firing the material forming the color filter 4 and the light shielding unit 5, and a plate-shaped mask 42 having an opening 42 a. . The opening 42a is formed at a location facing the color filter forming region R1. The mask 42 is formed so as to cover the light shielding portion forming region R2. The mask 42 is made of stainless steel. In addition, the mask 42 should just be formed by providing the opening part 42a in the inorganic flat plate using materials, such as stainless steel, glass, and earthenware.

Next, a method for manufacturing a liquid crystal display element will be described. In particular, a method for manufacturing the array substrate 1 as the light shielding portion forming substrate will be described in detail.
First, as a transparent insulating substrate, a mother glass 100 as a substrate having a size larger than that of the array substrate 1 is prepared, and the array substrate is formed using the mother glass. After that, two array substrates 1 are formed at the same time. Here, a manufacturing method thereof will be described on behalf of one array substrate.

  As shown in FIG. 2, the TFT 11, signal lines and scanning lines (not shown) are formed on the mother glass 100 by normal manufacturing processes such as repeated film formation and patterning. Thereafter, the process proceeds to the step of forming the color filter 4, the light shielding part 5, and the columnar spacer 31 on the mother glass 100 described above.

  As shown in FIG. 9, first, in step S1, when the formation process of the color filter 4, the light shielding portion 5, and the columnar spacer 31 is started, in step S2, a red resist 4Ra as a coloring resist is used to form the mother glass 100 using a spinner. Apply to the entire upper surface. The red resist 4Ra used here is, for example, a negative ultraviolet curable acrylic resin resist in which a red pigment is dispersed as a coloring pigment.

Next, as shown in FIG. 3, in step S3, the red resist 4Ra is exposed to patterning using a predetermined photomask 51. At the time of exposure, the red resist 4Ra is irradiated with ultraviolet rays with a wavelength of 365 nm and an exposure amount of 100 mJ / cm ² . Here, the photomask 51 used is a color filter forming region R1 in a stripe shape pattern in which ultraviolet rays are irradiated to a portion to be colored in red, and a frame shape in which ultraviolet rays are irradiated on the light shielding portion forming region R2. A pattern and a pattern for the contact hole 4h connecting the pixel electrode 17 and the TFT 11 are provided. Thereafter, in step S4, the exposed red resist 4Ra is developed with a 1% aqueous solution of KOH for 20 seconds. Thereby, the red resist layer 4R1 and the red resist layer 5R1 are simultaneously formed in the color filter forming region R1 and the light shielding portion forming region R2, respectively.

  Next, as shown in FIGS. 1 and 4, in step S <b> 5, the mother glass 100 on which the red resist layers 4 </ b> R <b> 1 and 5 </ b> R <b> 1 are formed is placed on the hot plate 41 of the manufacturing apparatus 40. Then, a mask 42 is placed on the red resist layer 5R1. At this time, the mask 42 is placed so that the opening 42a faces the color filter forming region R1. Thereby, the red resist layer 5R1 is entirely covered with the mask. Subsequently, the hot plate 41 is heated, and the red resist layers 4R1 and 5R1 are temporarily baked at 200 ° C. for 5 minutes.

  Here, the inventors of the present invention set the solvent residual ratio of the red resist layers 4R1, 5R1 immediately after the applied red resist 4Ra is exposed and developed to 100%, and the solvent residual ratio when the solvent evaporation is saturated by heating. The solvent residual ratio was determined with 0%. In addition, the solvent residual rate was calculated | required by measuring the mass of red resist layer 4R1, 5R1.

  When the solvent residual ratio of the red resist layers 4R1, 5R1 was determined, the solvent residual ratio of the red resist layer 4R1 not covered with the mask 42 was 1% or less, and the solvent of the red resist layer 5R1 covered with the mask 42 was The residual rate was 80%.

  Next, in step S6, a green resist 4Ga as a colored resist is applied to the entire surface of the mother glass 100 using a spinner. The green resist 4Ga used here is, for example, a negative ultraviolet curable acrylic resin resist in which a green pigment is dispersed as a coloring pigment. As a result, the green pigment 4 of the green resist 4Ga applied over the insufficiently baked red resist layer 5R1 is adsorbed to the red resist layer 5R1.

Next, as shown in FIG. 5, in step S7, the green resist 4Ga is exposed to patterning using a predetermined photomask 52. At the time of exposure, the green resist 4Ga is irradiated with ultraviolet rays with a wavelength of 365 nm and an exposure amount of 100 mJ / cm ² . Here, the photomask 52 used is a color filter forming region R1, a stripe shape pattern in which ultraviolet rays are irradiated to a portion to be colored green, and a pattern for a contact hole 4h connecting the pixel electrode 17 and the TFT 11 And have. Thereafter, in step S8, the exposed green resist 4Ga is developed with a 1% aqueous solution of KOH for 20 seconds. Thereby, the green resist layer 4G1 is formed in the color filter forming region R1. The green pigment G is maintained in a state of being adsorbed on the red resist layer 5R1.

  Next, as shown in FIGS. 1 and 6, in step S <b> 9, the mother glass 100 on which the green resist layer 4 </ b> G <b> 1 is formed is placed on the hot plate 41 of the manufacturing apparatus 40. Then, the mask 42 is placed on the red resist layer 5R1 on which the green pigment G is adsorbed. At this time, the mask 42 is placed so that the opening 42a faces the color filter forming region R1. Thereby, the red resist layer 5R1 is entirely covered with the mask. Subsequently, the hot plate 41 is heated, and the red resist layers 4R1, 5R1 and the green resist layer 4G1 are temporarily baked at 200 ° C. for 5 minutes.

  Here, the inventors of the present application set the solvent residual rate of the green resist layer 4G1 immediately after the applied green resist 4Ga is exposed and developed to 100%, and the solvent residual rate when the solvent evaporation is saturated by heating to 0%. The solvent residual ratio of the green resist layer 4G1 was determined by measuring the mass of the green resist layer 4G1. Further, the solvent residual ratio of the red resist layer 5R1 was also obtained.

  When the solvent residual ratio of the red resist layer 5R1 and the green resist layer 4G1 was determined, the solvent residual ratio of the red resist layer 5R1 covered with the mask 42 was 70%, and the green resist layer 4G1 not covered with the mask 42 The solvent residual ratio of was 1% or less. At this time, the light transmitted through the light shielding portion forming region R2 toward the display surface S is a mixed color of red and green.

  Subsequently, as shown in FIG. 10, in step S <b> 10, a blue resist 4 </ b> Ba as a colored resist is applied on the entire surface of the mother glass 100 using a spinner. The blue resist 4Ba used here is, for example, a negative ultraviolet curable acrylic resin resist in which a blue pigment is dispersed as a color pigment. As a result, like the green pigment G, the blue pigment B of the blue resist 4Ba applied over the insufficiently baked red resist layer 5R1 is adsorbed to the red resist layer 5R1.

Next, as shown in FIG. 7, in step S11, the blue resist 4Ba is exposed to patterning using a predetermined photomask 53. At the time of exposure, the blue resist 4Ba is irradiated with ultraviolet rays with a wavelength of 365 nm and an exposure amount of 100 mJ / cm ² . Here, the photomask 53 used is a color filter formation region R1 and a stripe shape pattern that irradiates ultraviolet rays to a portion to be colored green, and a pattern for a contact hole 4h that connects the pixel electrode 17 and the TFT 11 And a pattern in which ultraviolet rays are irradiated to a portion where the columnar spacer 31 is desired to be formed. Thereafter, in step S12, the exposed blue resist 4Ba is developed with a 1% aqueous solution of KOH for 20 seconds. As a result, the blue resist layer 4B1 is formed in the color filter forming region R1, and the columnar spacers 31 having a film thickness of 3.0 μm are formed on the red resist layer 4R1. The green pigment G and the blue pigment B are maintained in a state of being adsorbed on the red resist layer 5R1.

  Next, as shown in FIG. 8, in step S13, the mother glass 100 on which the blue resist layer 4B1 is formed is placed on the hot plate 41 of the manufacturing apparatus 40. Subsequently, the hot plate 41 is heated without placing the mask 42, and the red resist layers 4R1, 5R1, the green resist layer 4G1, and the blue resist layer 4B1 are subjected to main baking at 220 ° C. for 1 hour.

  Thereby, the red resist layers 4R1, 5R1, the green resist layer 4G1, and the blue resist layer 4B1 are cured, and the colored layers 4R, 5R, the colored layer 4G, and the colored layer 4B having a thickness of about 3.0 μm are formed. The In the light shielding part forming region R2, the light shielding part 5 having a thickness of about 3.0 μm is formed by adsorbing the green pigment G and the blue pigment B to the colored layer 5R. Thereby, the process of forming the color filter 4, the light shielding part 5, and the columnar spacer 31 is completed (step S14). The light shielding portion 5 viewed from the display surface S is black, and light incident on the light shielding portion forming region R2 toward the display surface is shielded by the light shielding portion.

  Thereafter, a plurality of pixel electrodes 17 are formed on the contact holes 4h and the colored layers 4R, 4G, and 4B using ITO (indium tin oxide) as a transparent conductive material. Subsequently, an alignment film material is applied to the entire surface of the mother glass 100 to a film thickness of 100 nm to form an alignment film 18. The alignment film 18 is subjected to a predetermined alignment process (rubbing). As a result, two array substrates 1 are formed on the mother glass 100.

  on the other hand. The counter substrate 2 forms a counter electrode 21 made of, for example, ITO as a transparent conductive material on the glass substrate 20, and applies the alignment film material to a thickness of 100 nm on the counter electrode to form the alignment film 22. To do. The alignment film 22 is subjected to a predetermined alignment process (rubbing).

  Next, for example, a thermosetting sealing material 32 is printed along the periphery of the glass substrate 20, and then an electrode transition material is formed in the vicinity of the sealing material. Subsequently, the counter substrate 2 is opposed to the array substrate 1, and the counter substrate is bonded to the mother glass 100 using the sealing material 32. Thereafter, the sealing material 32 is heated and cured to fix the mother glass 100 and the counter substrate 2. Subsequently, the mother glass 100 is divided along the periphery of the array substrate 1. Thus, two sets of empty liquid crystal cells are obtained. The array substrate 1 and the counter substrate 2 hold a predetermined gap by a plurality of columnar spacers 31.

  Subsequently, liquid crystal having a positive dielectric anisotropy is injected from a liquid crystal injection port formed in a part of the sealing material 32 by vacuum injection. Thereafter, the liquid crystal injection port is sealed with a sealing material made of, for example, an ultraviolet curable resin. As a result, liquid crystal is sealed between the array substrate 1, the counter substrate 2, and the sealing material 32, and the liquid crystal layer 3 is formed. Next, the polarizing plate 6 and the phase difference plate 7 are arranged on the outer surface of the array substrate 1, and the polarizing plate 8 and the phase difference plate 9 are arranged on the outer surface of the counter substrate 2 in this order. Further, the backlight unit L is arranged on the outer surface of the phase difference plate 7 and assembled into a module. Thereby, a liquid crystal display element is completed.

  As shown in FIG. 11, when the OD value was measured using the liquid crystal display element completed in the present embodiment, the OD value of the light shielding part 5 was 4.5, and sufficient light shielding performance was obtained. Furthermore, the contrast ratio was uniformly as high as 500: 1 over the entire display screen, and a liquid crystal display device excellent in display quality was obtained. The response speed of the liquid crystal display element was 20 ms, and high-speed response could be realized. The liquid crystal display element was continuously lit for 1000 hours in an environment of high temperature (60 ° C.) and high humidity (80%), and a reliability test was conducted, but there was no display unevenness and image sticking, and the display quality was good. It was confirmed that this was a highly reliable liquid crystal display element.

  According to the method of manufacturing a liquid crystal display element configured as described above, the green pigment G of the green resist 4Ga and the blue pigment B of the blue resist 4Ba are formed on the red resist layer 5R1 formed by applying the red resist 4Ra. The light-shielding part 5 is formed by adsorbing. When the light shielding portion 5 is formed, the red resist layer 5R1 is heated so that the residual ratio of the solvent in the red resist layer 5R1 after heating is different from the residual ratio of the solvent in the red resist layer 5R1 before heating. . More specifically, when the red resist layers 4R1 and 5R1 and the green resist layer 4G1 are formed, the red resist layer 5R1 on which the mask 42 is placed is heated to form an uncured red resist layer 5R1, whereby the red color after heating The light shielding portion 5 is formed by lowering the solvent residual ratio of the resist layer 5R1 lower than the solvent residual ratio of the red resist layer 5R1 before heating.

  For this reason, high-speed response is realized by narrowing the cell gap, and even if the film thickness of the light shielding part 5 is about 3.0 μm, sufficient light shielding performance can be obtained by forming the light shielding part 5 as described above. Can be obtained. From the above, when the OD value of the light shielding part 5 is formed with a film thickness of about 3.0 μm and the pigment concentration of the colored layer 5R is higher than the pigment concentration of the red resist 4Ra, the light shielding part 5 is formed of a black resist. It can be seen that the OD value when the green pigment G and the blue pigment B are formed on the red resist layer 5R1 is higher than the OD value when the OD value is formed. As a result, light leakage at the light shielding portion 5 can be suppressed, and a method for manufacturing a liquid crystal display element excellent in display quality can be obtained.

  Further, since the color filter 4 and the columnar spacer 31 can be formed of the same material at the same time when forming the light shielding portion 5, the color filter, the light shielding portion, and the columnar spacer can be efficiently formed without increasing the manufacturing process. it can.

  Next, the reason why the OD value of the light shielding part 5 in the above-described embodiment is higher than the OD value of the light shielding part formed of black resist will be described. That is, the reason why the light-shielding portion with a high OD value cannot be formed with a black resist will be described. Since the OD value of the light shielding part depends on the film thickness of the light shielding part, a sufficient film thickness is necessary to obtain a sufficient OD value. Usually, in a pigment-dispersed colored resist, the pigment concentration that can be contained in the colored resist is about 30% to 40% or less from the viewpoint of dispersion stability. When the light-shielding portion 5 is formed by dispersing a colored resist having good light absorption such as carbon black, a sufficient OD value can be obtained even if the thickness of the light-shielding portion is small. However, since carbon black is conductive, the reliability of the product is lowered.

  If a colored pigment having sufficiently high resistance and reliability is used, it is conceivable to increase the pigment concentration in order to increase the OD value. In this case, however, exposure during pattern formation does not reach the depth of the colored resist. At the time of development, the deep part where the light did not reach is dissolved, so that the workability becomes a problem such as a so-called reverse taper shape. From the above, it is impossible to form a light-shielding portion having a high OD value and a thin film thickness using a black resist.

  Further, unlike the above-described embodiment, the inventors of the present invention set the time for heating the green resist 4Ra, that is, the time for temporary baking of the green resist to 20 minutes, 30 minutes, 40 minutes, and 60 in step S9. The solvent residual ratio of the red resist layer 5R1 and the appearance of the light-shielding part 5 after firing the blue resist layer 4B1 were investigated respectively. Appearance of the light-shielding part 5 is ◯ when sufficient light-shielding performance is obtained, △ when sufficient light-shielding performance is not obtained but the light-shielding performance is not a problem, and when light shielding is insufficient. Each was evaluated with x. In addition, the liquid crystal display element was manufactured similarly to embodiment mentioned above except having changed the time of temporary baking of green resist 4Ra.

As shown in FIG. 11, when the solvent residual ratio of the red resist layer 5R1 is 20%, the light shielding part 5 viewed from the display surface S is black as in the above-described embodiment, and sufficient light shielding performance is obtained. When the solvent residual ratio of the red resist layer 5R1 was 10%, the light shielding portion 5 viewed from the display surface S was light black, but there was no problem in the light shielding performance. However, when the solvent residual ratio of the red resist layer 5R1 is 2%, the light shielding portion 5 viewed from the display surface S is a mixed color of red and green, and the OD value of the light shielding portion is less than 1.0. Since light omission occurs in the light shielding portion 5 and light of mixed colors of red and green is displayed on the display surface S, the light shielding performance is insufficient.
As described above, when forming the light-shielding portion 5, the green resist G5 and the blue pigment B of the blue resist 4Ba are adsorbed on the red resist layer 5R1 having a solvent residual ratio of at least 10% or more. The layer 5 may be formed. Further, the solvent residual ratio of the red resist layer 5R1 is not limited to the adjustment of the heating time (baking time) but may be varied by adjusting the heating temperature (baking), or may be varied by adjusting the heating time and the heating temperature. May be.

  When the liquid crystal display element is completed by setting the residual ratio of the solvent of the red resist layer 5R1 to 10% or more, the contrast ratio is uniformly as high as 500: 1 over the entire display screen, and a liquid crystal display element excellent in display quality can be obtained. It was. The response speed of the liquid crystal display element was 20 ms, and high-speed response could be realized. The liquid crystal display element was continuously lit for 1000 hours in an environment of high temperature (60 ° C.) and high humidity (80%), and a reliability test was performed. It was confirmed that this was a highly reliable liquid crystal display element.

(Comparative example)
In the comparative example, in step S9, the red resist layer 5R1 was heated (fired) without placing the mask 42 even when the green resist 4Ra was baked to manufacture a liquid crystal display element. Note that a liquid crystal display element was formed in the same manner as in the above-described embodiment except that firing was performed without using the mask 42 in the above-described manner.

  In step S9, when the red resist layer 5R1 that is not covered with the mask 42 is baked and the solvent residual ratio of the baked red resist layer 5R1 is determined, the solvent residual ratio is 1% or less. The viewed red resist layer 5R1 remained red. Furthermore, when the red resist layer 5R1 that is not covered with the mask 42 is baked in Step S13 and the residual solvent ratio of the red resist layer 5R1 after baking is determined, the residual solvent ratio in this case is also 1% or less. The red resist layer 5R1 viewed from the display surface S remained red.

In the liquid crystal display element of the comparative example,
The contrast ratio was as high as 500: 1 and the display characteristics were high. The response speed of the liquid crystal display element was 20 ms, and high-speed response could be realized. The liquid crystal display element was continuously lit for 1000 hours in an environment of high temperature (60 ° C.) and high humidity (80%), and a reliability test was performed. It was confirmed that this was a highly reliable liquid crystal display element. However, the OD value of the light shielding part 5 was less than 1.0. Needless to say, the light shielding performance is insufficient because light leakage occurs in the light shielding portion 5 and red light is displayed on the display surface S.

  The present invention is not limited to the above-described embodiment, and can be variously modified within the scope of the present invention. For example, the mask 42 should just be formed by providing the opening part 42a in the mesh-shaped inorganic flat plate. Thereby, the solvent volatility can be controlled, and the solvent of the red resist layer 5R1 can be uniformly left.

  The order in which the colored resist is applied is not limited to the above-described embodiment, and the red resist, the green resist, and the blue resist may be applied in any order, so that the light shielding portion 5 has sufficient light shielding performance. As long as it has.

  When the color filter 4 and the light shielding part 5 are not formed simultaneously with the same material, the material for forming the light shielding part is not limited to the red resist, the green resist, and the blue resist. When forming the light-shielding portion 5, a plurality of colored resists are applied on the glass substrate 10 in a plurality of times and applied to the colored resist layer formed by the first application of the colored resist at least the second and subsequent times. The light-shielding portion may be formed by adsorbing the colored pigment of the colored resist.

For this reason, it is possible to form the light shielding part 5 using at least two kinds of colored resists, and when forming the light shielding part, the first colored resist is applied on the glass substrate 10 to form a colored resist layer. Then, by applying a second colored resist different from the first colored resist over the colored resist layer, the colored pigment of the second colored resist is adsorbed on the colored resist layer to form a light shielding portion. And the light-shielding part 5 should just have sufficient light-shielding performance.
The color filter 4, the light shielding part 5, and the columnar spacer 31 are formed on the array substrate 1 side. However, the color filter 4, the light shielding part 5, and the columnar spacer 31 are not limited thereto, and may be formed on the counter substrate 2 side as the light shielding part forming substrate.

The schematic perspective view which shows the manufacturing apparatus of the light-shielding part of the liquid crystal display element which concerns on embodiment of this invention. Sectional drawing which shows the manufacturing process of the light-shielding part of the liquid crystal display element which concerns on embodiment of this invention, and a color filter. Sectional drawing which shows the manufacturing process of the said light shielding part and rar filter following FIG. Sectional drawing which shows the manufacturing process of the said light-shielding part and color filter following FIG. Sectional drawing which shows the manufacturing process of the said light-shielding part and color filter following FIG. Sectional drawing which shows the manufacturing process of the said light-shielding part and color filter following FIG. Sectional drawing which shows the manufacturing process of the said light-shielding part and color filter following FIG. Sectional drawing which shows the manufacturing process of the said light-shielding part and color filter following FIG. FIG. 7 is a flowchart for forming a light shielding portion and a color filter shown in FIGS. 2 to 6. FIG. 9 is a flowchart for forming a light shielding portion and a color filter shown in FIG. 7 and FIG. 8 following FIG. 9. The figure which showed the change of the solvent residual amount of a colored resist layer at the time of forming a light-shielding part by changing baking time, and the change of OD value with a table | surface. Sectional drawing which shows the liquid crystal display element manufactured by the manufacturing method of the liquid crystal display element which concerns on embodiment of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Array substrate, 2 ... Counter substrate, 3 ... Liquid crystal layer, 4 ... Color filter, 4R, 4G, 4B, 5R ... Colored layer, 4Ra ... Red resist, 4Ga ... Green resist, 4Ba ... Blue resist, 4R1, 5R1 ... Red resist layer, 4G1 ... green resist layer, 4B1 ... blue resist layer, 5 ... light-shielding part, 10,20 ... glass substrate, 40 ... production apparatus, 41 ... hot plate, 42 ... mask, 42a ... opening, 100 ... mother Glass, G, B ... pigments.

Claims (11)

An array substrate having a plurality of wirings and a plurality of switching elements connected to the plurality of wirings, a counter substrate disposed opposite to the array substrate while maintaining a gap, and sandwiched between the array substrate and the counter substrate In a method for manufacturing a liquid crystal display element comprising: a liquid crystal layer that is formed; and a light-shielding portion formed on one of the array substrate and the opposing substrate.
A plurality of colored resists are applied to the light-shielding portion forming substrate in a plurality of times, and a colored resist color pigment applied at least a second time is applied to a colored resist layer formed by applying the first colored resist. A method of manufacturing a liquid crystal display element, wherein the light shielding portion is formed by adsorption.   2. The liquid crystal display element according to claim 1, wherein by heating the colored resist layer, the solvent residual ratio of the colored resist layer after heating is different from the solvent residual ratio of the colored resist layer before heating. Manufacturing method. After placing a mask on the colored resist layer,
By heating the colored resist layer to form the uncured colored resist layer, the solvent residual rate of the colored resist layer after heating is different from the solvent residual rate of the colored resist layer before heating, 2. The method of manufacturing a liquid crystal display element according to claim 1, wherein the residual solvent rate of the colored resist layer on which the mask is placed is different from the residual solvent rate of the colored resist layer on which the mask is not placed. The mask is mesh-shaped;
The method for manufacturing a liquid crystal display element according to claim 3, wherein the colored resist layer on which the mesh-shaped mask is mounted is heated.   4. The method according to claim 2, wherein during the heating, the heating time and the heating temperature are adjusted so that the solvent residual ratio of the colored resist layer after the heating is different from the solvent residual ratio of the colored resist layer before the heating. The manufacturing method of the liquid crystal display element of description. When the solvent residual ratio of the colored resist layer immediately after exposing and developing the colored resist applied for the first time is 100%, and when the solvent evaporation is saturated by heating, the solvent residual ratio is 0%.
2. The liquid crystal display according to claim 1, wherein the light shielding portion is formed by adsorbing a colored pigment of a colored resist applied at least a second time or more to a colored resist layer having a solvent residual ratio of 10% or more. Device manufacturing method.   2. The liquid crystal display according to claim 1, wherein a red resist, a green resist, and a blue resist are applied as a plurality of colored resists on the light shielding portion forming substrate to form the light shielding portion. Device manufacturing method.   The liquid crystal display element according to claim 7, wherein when forming the light shielding portion, a color filter including a red colored layer, a green colored layer, and a blue colored layer is simultaneously formed using the plurality of colored resists. Production method.   The method for manufacturing a liquid crystal display element according to claim 7, wherein when forming the light shielding portion, a columnar spacer that holds a gap in the array substrate is simultaneously formed using the colored resist.   The method for manufacturing a liquid crystal display element according to claim 1, wherein the light shielding portion is formed on the array substrate. An array substrate having a plurality of wirings and a plurality of switching elements connected to the plurality of wirings, a counter substrate disposed opposite to the array substrate while maintaining a gap, and sandwiched between the array substrate and the counter substrate In a method for manufacturing a liquid crystal display element comprising: a liquid crystal layer that is formed; and a light-shielding portion formed on one of the array substrate and the opposing substrate.
Applying a first colored resist on the light shielding part forming substrate to form a colored resist layer;
Applying a second colored resist different from the first colored resist on the colored resist layer to adsorb the colored pigment of the second colored resist to the colored resist layer to form the light shielding portion. A method for manufacturing a liquid crystal display element.

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