JP2009020396A - Color filter, liquid crystal display device using the same and method of manufacturing color filter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a color filter which does not cause light leakage from anywhere of a colored part in the color filter having a transparent colored layer and a retardation layer; and to provide a method of manufacturing the color filter using a photolithography, which does not cause light leakage from anywhere of the colored part with respect to the manufacturing method of color filter. <P>SOLUTION: The color filter, where a substrate, the transparent colored layer and the retardation layer are formed in the order, is fundamentally characterized in that: the cross-sectional contour of the colored part constituting the transparent colored part does not substantially incline in the one-sided direction; and liquid crystal molecules constituting the retardation layer positioned on the upper surface of the colored part are preferably oriented. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

The present invention relates to a color filter, a liquid crystal display device using the same, and a method of manufacturing the same, and more specifically, a color filter including a transparent coloring layer composed of colored transparent colored portions of even-numbered colors of four or more colors. The present invention relates to a liquid crystal display device used and a manufacturing method thereof.

  At present, liquid crystal display devices capable of color display (color liquid crystal display devices) are widely used. On the viewer side of a general color liquid crystal display device, a color filter in which colored portions corresponding to pixels (dots) are finely patterned is provided as a display side substrate, and a liquid crystal drive substrate including a liquid crystal drive electrode is provided. A liquid crystal cell is formed by sandwiching driving liquid crystal molecules between them, and this is switched for each pixel to switch between bright display (white display) and dark display (black display). In a typical color filter, colored portions of three colors corresponding to the three primary colors of red (R), green (G), and blue (B) are repeatedly arranged side by side in stripes at each pixel width. A transparent colored layer is formed. Three pixels (dots) of R, G, and B constitute one picture element (pixel), and each picture element can perform color display by the additive color mixing method.

  In recent years, in order to express more complex colors, the above three colored portions are provided with complementary colored portions such as yellow (hereinafter also referred to as “Y”) and cyan (hereinafter also referred to as “C”). There has been proposed a color filter including a transparent colored layer constituted by the added four colored portions. For example, Patent Document 1 proposes a method for improving the color reproducibility of a color liquid crystal display device. In the liquid crystal display device described above, the area of one color pixel is composed of pixels of four colors such as C in addition to RGB. The transparent colored layer may be patterned in two vertical and horizontal orthogonal matrix patterns or in two oblique directions in addition to repeating the stripe-shaped colored portions arranged side by side as described above.

  In addition, a color filter including four pixels obtained by adding a colorless and transparent pixel to a basic three primary colors of RGB to a colorless and transparent (hereinafter also referred to as “W”) pixel for white display has been proposed (for example, Patent Document 2 below). Patent Document 3). Since the W pixel has higher light utilization efficiency than the other pixels, the color filter in which the W pixel is added to RGB is a color filter proposed mainly for improving the luminance of white display.

  By the way, in recent years, as an optical element used in a liquid crystal display device or the like, an optical element that provides a retardation layer in a substrate in order to expand a viewing angle has been developed (for example, Patent Document 4 below). This is a so-called in-cell structure in which a cross-linkable liquid crystal material is fixed in a state of being oriented in a desired direction directly or indirectly on a substrate instead of a retardation film that has been conventionally attached to the outside of the substrate. An optical element provided with a retardation layer. By forming a transparent colored layer in the optical element having the in-cell retardation layer, it can be used as a color filter substrate.

JP 2006-267541 A Japanese Patent Laid-Open No. 5-88011 JP 2006-259135 A JP 2004-240102 A

  However, when a color filter substrate having a transparent colored layer composed of a plurality of colored portions between a substrate and an in-cell retardation layer (hereinafter also simply referred to as a “retardation layer”) is formed, transmitted light is transmitted to the substrate. It has been found that light leakage may occur partially when the light is transmitted (hereinafter, also simply referred to as “light leakage problem”).

Therefore, the present inventor has studied in detail the above-described light leakage problem of the color filter. As a result, the color filter is provided with a transparent colored layer composed of a plurality of colored portions, and it has been found that light leakage may occur in a specific colored portion portion of the transparent colored layer. The light leakage at the specific colored portion is caused by the light leakage problem of the conventional color filter, which is a problem.

  The problem of the light leakage of the specific colored portion is that when the transparent colored layer is composed of four or more colored portions, particularly when the arrangement pattern of the colored portions is striped, or there are a plurality of colored portions. In a pattern in which all colored portions are repeatedly formed in at least one direction in the form of a matrix composed of rows and columns, there is a problem in the entire transparent colored layer (that is, the entire effective display area).

Even when light leakage is not confirmed in the entire transparent colored layer, light leakage is confirmed at least in the colored portion existing at the extreme end of the transparent colored layer (that is, the critical portion of the effective display area). was there. In such a case, a solution may be considered in which only the black matrix line width in the critical portion of the effective display area is designed to be particularly large so that the area where light leakage may occur is blocked. However, for a small display such as a mobile phone, there is a demand for securing a display area as large as possible within a physically limited area, and it is not desirable to shield the critical part of the effective display area. There was a case. Of course, there are color filters that are not provided with a black matrix. In such color filters as well, light leakage in the critical portion of the effective display area may be a problem.

  The present invention has been made in view of the above-described problem of light leakage of the color filter. In a color filter having a transparent colored layer and a retardation layer, the color in which light leakage does not occur from any of the colored portions. It is an object of the present invention to provide a filter and a color filter manufacturing method using a photolithography method, in which light leakage does not occur from any of the colored portions.

As a result of diligent efforts by the present inventors, it has been found that, among the colored portions constituting the transparent colored layer, the outer shell of the vertical cross section parallel to the repeating direction is formed with an inclination that is practically biased in one direction. More specifically, when the cross-section outer shell of the colored portion cut by an arbitrary vertical plane parallel to the repeating direction of each colored portion is observed, any one color is used in the transparent colored layer composed of the three colored portions. In the colored portion of the transparent colored layer composed of the four colored portions, in the colored portion of one color or two colors, the cross-sectional outer shell is left and right non-contrast and is inclined substantially in one direction. It was.

Among the crosslinkable liquid crystal materials constituting the retardation layer formed on the transparent colored layer, the orientation of the crosslinkable liquid crystal material existing above the colored portion where the inclined gradient is formed is regulated by the inclination. I found out that it was confused. In addition, light leakage has occurred at the location where the above alignment failure has occurred, and the color filter substrate in which such light leakage has occurred is used as a substrate on one side of a display device such as a liquid crystal display device. In addition, it was found that the display image quality deteriorates.

  Therefore, the color filter substrate of the present invention has the substrate, the transparent colored layer, and the retardation layer in this order. Based on the above knowledge, the transparent colored layer provided in the color filter constitutes the transparent colored layer. The colored shell is essentially characterized in that the outer shell of the cross section of the colored portion is not substantially inclined in one direction, and the method for producing a color filter according to the second invention is a photolithography method. When forming each colored portion, the colored portion is formed at a position not adjacent to any colored portion, or a further colored portion is formed in a region where the colored portion already formed at the left and right positions is present. It is a basic feature.

That is, the present invention
(1) A retardation formed by fixing a transparent colored layer composed of at least an even number and four or more colored portions and a crosslinkable liquid crystal material in a desired direction, directly or indirectly on a substrate. A color filter comprising layers in this order, wherein the colored portions are arranged in a predetermined pattern in order with at least one direction as a repeating direction, and the colored portions are cut in a vertical section in the repeating direction. A color filter characterized in that the cross-section outer shell is not substantially inclined and inclined in one direction;
(2) The color filter as described in (1) above, wherein the cross-section outer shell of each colored portion is substantially symmetrical
(3) The color filter as described in (1) or (2) above, wherein a substantially flat outer shell portion exists in the left-right direction from the central portion of the cross-section outer shell of each colored portion.
(4) The color filter according to any one of (1) to (3) above, wherein a black matrix layer is provided on the substrate and below the transparent colored layer.
(5) Two substrates are opposed to each other, a driving liquid crystal layer is provided in a space formed between the substrates, and a voltage is applied to change the orientation of driving liquid crystal molecules filled in the driving liquid crystal layer. In the liquid crystal display device having a multilayer structure in which a layer including an electrode portion is provided and a polarizing plate is stacked on the outside of the two substrates, the color filter according to (1) to (4) described above is used as one substrate. A liquid crystal display device characterized by being used;
(6) A method for producing a color filter comprising a transparent colored layer composed of an even number of four or more colored portions arranged in a predetermined pattern in order with at least one direction as a repeating direction directly or indirectly on a substrate Then, by a photolithography method, a colored portion of one color is formed at a position where a colored portion is to be formed on the substrate at a position arbitrarily selected in a predetermined pattern, and the colored portion formed first is first, Next, in the colored portion formation scheduled area where the colored portion is not yet formed, the odd-numbered positions toward the one direction of the predetermined pattern with respect to the colored portion formed first, or two already formed colored portions The transparent colored layer is formed by forming a colored portion after the second color at a position adjacent to the portion, and then crosslinked directly or indirectly on the transparent colored layer. A liquid crystal composition containing a liquid crystal material is applied to form a coating film, the crosslinkable liquid crystal material present in the coating film is oriented in a desired direction, and then the coating film is irradiated with light and / or heat. The color filter according to any one of (1) to (4) above, wherein the retardation layer is formed by crosslinking and fixing the crosslinkable liquid crystal material in an aligned state. Manufacturing method,
(7) The method for producing a color filter as described in (6) above, wherein the pattern in which the colored portions constituting the transparent colored layer are arranged is a stripe shape,
(8) The formation position of the first color of the colored stripe pattern is an odd number including the colored portion corresponding to the extreme end of the effective display region or the colored portion corresponding to the extreme end of the effective display region. It is a coloring part, The manufacturing method of the color filter as described in said (7) characterized by the above-mentioned.
(9) The method for producing a color filter as described in (6) above, wherein the pattern in which the colored portions constituting the transparent colored layer are arranged is a matrix.
Is a summary.

  Hereinafter, some terms used in the present invention and the description for explaining the present invention will be explained.

In the present invention, “substantially not inclined in one direction” specifically refers to each color constituting the transparent colored layer in the present invention in which a retardation layer is formed on the transparent colored layer. This means that the outer shell of the cross section of the colored picture element does not show an inclination that is biased in one direction to the extent that alignment failure occurs in the crosslinkable liquid crystal material located on the picture element. As an example in which the outer shell of the cross section perpendicular to the longitudinal direction of the colored portion is not substantially inclined and inclined in one direction, it is desirable that the outer shell is flat. Even when there is an inclination, it includes the case where a flat portion is formed at the center of the width of the outer shell in the colored portion or in the vicinity thereof. More specifically, the lateral dimension of the outer shell in the colored portion is within a range of 35% on one side (70% on both sides) from the center of the width (for example, the lateral dimension when the cross-sectional outer shell of the colored portion is observed is about 100 μm to (If the predetermined interval is about 2.7 μm, it is appropriate that the predetermined interval is about 2.7 μm). Excludes only positive or negative cases. Depending on the display screen size, the horizontal dimension of the colored portion is also appropriately changed. For example, in the case of a small screen such as a mobile phone display screen, the sampling number may be small when the sampling interval is 2.7 μm. Therefore, as another indicator of the sampling interval, the range of 70% on both sides can be divided into about 20 to 40 equal parts in the width direction.

The outer shell having the above-mentioned cross section is particularly preferably “substantially symmetrical”. As an example of left-right symmetry, in addition to a pattern in which the outer shell is flat, in the cross-section outer shell of the colored portion, both ends swell and a pattern in which an upward slope is formed from the central region toward both ends, the central region is A pattern in which a downward slope is formed toward both ends of the swell, or a flat portion exists in the central area, and a downward slope is formed on both ends across the flat portion, and the flat portion is raised to both ends by calculation. An example is a pattern in which an inclination is formed, and the inclination to the both end portions is formed at substantially the same left and right angles.

More specifically, the "substantially bilaterally symmetrical" outer shell of the colored section in the present invention is more specifically, by measuring the color filter surface using a fine shape measuring instrument ET4000L (manufactured by Kosaka Laboratory), Can be confirmed. In the present invention, when the cross-sectional outer shell is “substantially bilaterally symmetric”, when the line width (lateral dimension when observing the cross-sectional outer shell) of one colored portion is 150 μm or less, the cross-sectional outer shell This means that the difference in height between the two ends of the sheet is 2500 mm or less. Further, when the line width of one colored portion (lateral dimension when the outer shell is observed) exceeds 150 μm, it means that the difference in height between both ends of the outer shell is 1700 mm or less.

  The colored portion that can absorb visible light having a specific wavelength means a colored and transparent colored portion, and does not include a colorless and transparent region that does not contain a pigment or the like.

  The “cross-section outer shell” refers to the outline of the upper surface portion in a cross-sectional shape obtained by cutting the colored portion perpendicularly with a plane parallel to the repeating direction of each colored portion, unless otherwise specified.

  In addition, in the constituent layers constituting the optical element of the present invention, the expression method meaning the vertical direction such as “upper”, “upper”, “upper surface” or “lower”, “lower”, “lower surface”, etc. When arranged in the orientation of the lower layer, in any constituent layer, the substrate surface side is expressed as the “down” direction, and the side opposite to the substrate surface is expressed as the “up” direction.

  In the present invention, the “effective display area” means an area where transmitted light is emitted / incident and predetermined display or observation is performed. For example, when the present invention is used as an optical member in a liquid crystal panel, It means an area corresponding to an image display area in the liquid crystal panel.

  In the transparent colored layer in the color filter substrate of the present invention, the cross-sectional outer shell of each colored portion constituting the transparent colored layer is not substantially inclined in one direction. Therefore, in the color filter substrate of the present invention, in the retardation layer formed directly or indirectly on the upper surface of the transparent colored layer, the orientation of the crosslinkable liquid crystal material constituting the same is inclined so that the cross-section outer shell of the colored portion is inclined. There is no possibility of causing orientation failure due to.

In particular, when the retardation layer is formed by vertically aligning and fixing the crosslinkable liquid crystal material, the protective film can be omitted for the purpose of flattening the upper surface of the transparent colored layer. Even in the case where the retardation layer is formed by horizontally aligning and fixing the material, the protective film can be made significantly thinner than before. Therefore, the color filter of the present invention can contribute to the thinning of the liquid crystal cell.

As a result, in the color filter substrate of the present invention, the above problem of light leakage is solved, and when the color filter substrate of the present invention is used as a substrate on one side of a display device such as a liquid crystal display device, It is possible to provide a high-quality full-color display generated from even-numbered and four or more colored portions, which can prevent deterioration in image quality due to a problem and reliably realize high contrast.

Moreover, since the color filter substrate of the present invention has an in-cell retardation layer, the phase of transmitted light can be adjusted well and the viewing angle can be expanded without laminating an in-cell film outside the substrate. .

  Further, according to the method for producing a color filter substrate of the present invention, an even number of four or more colored portions can be formed without changing the number of steps and labor from the conventional method for forming a transparent colored layer using a photolithography method. The upper surface is not substantially inclined in one direction simply by specifying the formation position in a region where no other colored portion exists on the left or right side, or a region where other colored portions exist on both the left and right sides. A colored part can be formed.

Below, the color filter of this invention and its manufacturing method are demonstrated using FIG. 1 and FIG. The cross section of the colored portion described in the drawings shown for explaining the present invention is actually changed from the aspect ratio and illustrated as a schematic shape in order to explain the shape of the outer shell of the cross section. In FIG. 2, the cross-section outer shell of each colored portion is illustrated as being flat, but this does not necessarily mean that the cross-section outer shell becomes flat according to the manufacturing method of the present invention. According to the manufacturing method of the present invention, the cross-section outer shell is prevented from being inclined substantially in one direction.

FIG. 1 shows a red (hereinafter sometimes simply referred to as “R”) colored portion 3, a yellow (hereinafter sometimes simply referred to as “Y”) colored portion 4, and a green (hereinafter simply referred to as “G”). ) A top view of the transparent colored layer 8 formed by forming the colored portions 5 and the colored portions 6 of the blue color (hereinafter simply referred to as “B”) colored portions 6 into stripes of a plurality of rows and one column. It is. 2 (2F) is a cross-sectional view of the color filter 7 including the transparent colored layer 8 and the retardation layer 9 of FIG. 1, and is a schematic cross-sectional view when cut in the XX direction in FIG. 2 (2A) to (2F) show a black matrix (hereinafter also referred to as “BM”) 2 on a glass substrate 1, a transparent colored layer 8 composed of four colored portions, and a retardation layer. 9 is divided into each step to show one aspect of the manufacturing method of the present invention for producing a color filter 7 having the above-described steps.

  First, BM2 is formed on the upper surface of a suitable glass substrate 1 by orderly patterning so that a space between the BM2s is a position where a colored portion is to be created (FIG. 2A). Next, the R colored portion 3 is formed by a photolithography method in accordance with the planned production position of the R colored portion (FIG. 2B). Subsequently, the Y colored portion 4 is formed in the same manner at a position that is not adjacent to the R colored portion 3 and is therefore a colored portion non-created region on both sides (FIG. 2C). That is, as shown in FIG. 2C, the second colored Y portion 4 is formed with odd colored portions in the row direction with the first colored R portion 3 as a reference (first). It is formed in the planned area.

  Then, as the third colored portion, the G colored portion 5 is similarly formed between the R colored portion 3 and the Y colored portion 4 (FIG. 2D). Further, as a colored portion of four color surfaces, a B colored portion 6 is formed between the Y colored portion 4 and the R colored portion 3 by the photolithography method as described above to form a transparent colored layer 8 (FIG. 2E). . As described above, the G coloring portion 5 and the B coloring portion 6 are formed in a region sandwiched between two already formed coloring portions. Finally, a composition containing a crosslinkable liquid crystal material was applied directly on the upper surface of the transparent colored layer to form a coating film, and the crosslinkable liquid crystal material contained in the coating film was aligned in a desired direction. Thereafter, the cross-linkable liquid crystal materials are fixed by cross-linking polymerization to form the retardation layer 9, and the color filter substrate 7 is completed (FIG. 2F). In the present specification, an embodiment in which the colored portions of RGBY of four colors are formed in the order of R, Y, G, and B will be described, but the transparent colored layer in the present invention is not limited to this and is used. The design of the type of the colored part and the creation area of the colored part may be changed as appropriate. The particularly important point regarding the manufacturing method of the present invention is that the first created colored portion is first, then the second color is formed at odd-numbered positions in the row direction, and the third color is formed at further odd-numbered positions. A color plane is formed, or the third and subsequent colored portions are formed at even-numbered positions adjacent to the colored portions already formed at odd-numbered positions.

  According to the manufacturing method of the present invention illustrated in FIG. 2, when the cross section perpendicular to the longitudinal direction of the colored portion is observed in the formed color filter, the cross-section outer shell is substantially biased in one direction. As a result, there is no problem of light leakage caused by the inclination. Hereinafter, a conventional example will be described as a comparison object, and according to the manufacturing method of the present invention, a mechanism will be described in which a colored portion whose cross-section outer shell is not substantially inclined and tilted in one direction is created.

First, as a conventional example, FIG. 6 shows an example of a transparent colored layer used in a conventional color filter having a problem of light leakage. FIG. 6 is a top view of the transparent colored layer 101 composed of the three colored portions of the R colored portion 102, the G colored portion 103, and the B colored portion 104. The transparent colored layer 101 is formed by patterning the colored portions 102, 103, and 104 in the order of R, G, and B into a stripe shape of a plurality of rows and one column by a photolithography method.

  Next, in FIG. 7, the BM 114 is patterned on the glass substrate 113, the transparent colored layer 101 is laminated thereon, and then the crosslinkable liquid crystal material 112 is aligned and fixed in a desired direction on the upper surface thereof. A schematic cross-sectional view of a color filter substrate 111 formed by forming a retardation layer 120 is shown. FIG. 7 is a cross-sectional view of the color filter 111 cut in the YY direction in FIG. As shown in FIG. 7, the R colored portion 102 and the B colored portion 104 created as the first color and the third color have respective cross-sectional outer shells formed so as to cope with left and right. On the other hand, the G-colored portion 103 formed as the second color has a left side (that is, the R-colored portion side) end portion that rises high toward the paper surface, and a right-side end portion that is lower than the end portion. An inclined surface is formed in one direction from the left side to the right side.

  And among the crosslinkable liquid crystal material 112 that constitutes the retardation layer 120 laminated on the upper surface of the transparent colored layer 101, controlled by the inclination in one direction observed in the cross-section outer shell of the G colored portion 103, The crosslinkable liquid crystal material 112 above the inclined outer shell causes alignment failure. In the conventional transparent colored layer 101, the portion where light leakage occurs is shown by a dotted frame in FIG. 6, and this light leakage portion is just the orientation of the crosslinkable liquid crystal material 112 positioned above the G coloring portion 103. Corresponds to the defective part.

  As described above, in the transparent colored layer 101 provided in the conventional color filter shown in FIG. 7, when each colored portion is formed by photolithography, in some colored portions (G colored portion in FIG. 7) The mechanism by which the cross-section outer shell can be inclined substantially in one direction is considered as follows.

The coating film formed by applying the colored resist to the substrate surface in the photolithography process is formed so as to cover the laminate already provided on the substrate surface. It is formed. Next, the film is covered with a photomask so as to have a desired patterning shape and exposed, and further, unexposed portions are washed away to form colored portions. At that time, if the exposure is performed including the area where the coating film is raised, the colored portion is completed in a shape that leaves the raised area.

  In view of the above-mentioned rising point, when looking at each colored portion in FIG. 7, the first R colored portion 102 formed first covers the BM 114 already formed on the glass substrate 113 and R A colored resist is applied to form a coating film (hereinafter also referred to as “R coating film”). Therefore, the R coating film becomes a slightly raised coating film on the BM 114. Next, in a region where the R colored portion is to be formed, the BM 114 is exposed by covering with a photomask so that a striped colored portion is formed on the end, and an unexposed portion is deleted to form an R colored portion. The As shown in FIG. 7, the cross-section outer shell of the R colored portion 102 formed in this way is formed in a shape in which the portion riding on the BM 114 is slightly raised to the left and right approximately equally.

  Next, regarding the G coloring portion 103 formed second, the G coloring resist is applied on the base material surface so as to cover the R coloring portion 102 and the exposed BM 114 (hereinafter referred to as “G”). Also referred to as “coating film”). ) Is formed. The G coating film swells greatly on the upper surface of the R colored portion 102, while the BM 114 has a smaller swell on the upper surface. Next, in the same manner as the method of exposing the R coating film, the G coating film is exposed to remove the unexposed portion, and a G colored portion is formed. As shown in FIG. 7, the cross-section outer shell of the G coloring portion 103 formed in this way is greatly swelled at the end portion on the R coloring portion 102 side, while the end portion on the opposite side is just as much as riding on the BM 114. As a result, a biased inclined surface that is inclined downward from the right side to the left side of the paper surface is formed.

  The B colored portion 104 formed at the end covers the already formed G colored portion 103 and R colored portion 102 and is coated with a B colored resist, so that the G colored portion 103 and the R colored portion 102 A coating film (hereinafter, also referred to as “B coating film”) that greatly rises on the upper surface is formed. Therefore, when the formation area of the B colored portion is exposed and the unexposed portion is removed to form the B colored portion, the outer shell of the cross-section becomes a shape in which the left and right ends are greatly raised.

  In the above description, as exemplified in the formation of the R colored portion 102, the G colored portion 103, and the B colored portion 104, the colored portion formed by the photolithography method is governed by the shape of the laminate already existing on the substrate surface. It is understood that the shape of the coating film made of the colored resist is determined, the unexposed portion is removed while the shape is maintained, and the shape of the colored portion that is the remaining portion is determined. Therefore, when the process of applying a colored resist to form a coating film, covering with a photomask, exposing, and removing the unexposed portion is one cycle, a transparent colored layer composed of three colored portions is formed. When trying to form from three cycles by the photolithography method, an inclination that is substantially biased in one direction is formed in the outer shell of the cross section in the second colored layer. Also, in the case of four color filters, the same problem occurs in the second and third colored layers if the colored layers are formed in order, for example, adjacent to each other. .

  On the other hand, in the manufacturing method of the present invention, the first colored portion is formed, and then the second colored portion is an odd-numbered position in the left-right direction with reference to the first formed colored portion. Or it forms in the position pinched | interposed adjacent to two already formed coloring parts. In other words, in the manufacturing method of the present invention, the colored portions formed in a plurality of rows and one column or more are not formed with other colored portions in the adjacent left and right regions, or already in both the left and right regions. Therefore, when a colored resist is applied to form a coating film, the swell of the coating film is substantially bilaterally symmetrical about the colored part formation planned area. As a result, when the cross-sectional shape perpendicular to the longitudinal direction of the colored portion finally formed is observed, the outer shell of the cross-section is not substantially inclined in one direction.

  Thus, in the color filter of the present invention manufactured by the above manufacturing method, as shown in FIG. 3, when the cross-sectional shape perpendicular to the longitudinal direction of the colored portion is observed, the outer shell of the cross-section is substantially in one direction. Therefore, the orientation of the crosslinkable liquid crystal material disposed on the upper surface of the transparent colored layer is not disturbed by the shape of the upper surface of the transparent colored layer. Therefore, the problem of light leakage due to the inclination does not occur.

As described above, the color filter of the present invention including the transparent colored layer and the retardation layer composed of four or more colored transparent colored portions can be easily formed by the production method of the present invention. However, the manufacturing method of the color filter of the present invention including the transparent colored layer whose cross-section outer shell is not substantially inclined in one direction is not limited to the manufacturing method of the present invention. Moreover, according to the manufacturing method of the present invention, the present invention is not limited to the case of forming a transparent colored layer composed of four or more even-colored colored portions, and transparent coloring composed of three colored transparent colored portions. It can also be used for the production of color filters with layers. However, when a transparent colored layer comprising three colored transparent colored portions is prepared according to the production method of the present invention, this is regarded as pseudo six colors, and two cycles of steps are required for each colored colored portion. Therefore, attention should be paid to increasing the number of conventional processes.

  In the above description, the color filter of the present invention has been described using the transparent colored layer in which each colored portion is patterned in a stripe shape of a plurality of rows and one column, but the pattern of the transparent colored layer in the present invention is not limited thereto, Other patterns such as a matrix of a plurality of rows and a plurality of examples may be used as long as they are arranged in a plurality of rows and at least one column.

  When the BM is provided in the color filter, one colored portion is formed between the two BMs, and the hems of two adjacent colored portions are formed on the upper surface of one BM. Is common. This is because when the color filter is used for a liquid crystal cell or the like, the BM region is a light shielding region, and the BM is an opening region, so that the specified colored portion exists without a gap in the opening region. There is a need. Therefore, it is common that the skirt portion of the colored portion is formed on the BM.

  Here, the configuration of two adjacent colored portions that run on the BM can be roughly classified as follows. That is, (1) they are not in contact with each other on the BM, (2) they are in contact with each other on the BM, and (3) one is on the other on the BM. be able to. In particular, in the case of patterning a colored portion by photolithography, the colored portion previously formed on the BM is first coated with the colored portion constituting the other colored portion. Since this is applied and exposed to remove the excess part, before exposure, one side must be on top of the other, and in recent years the BM line width has been reduced to enlarge the opening area. Since there exists a tendency to form, it can be said that the relationship of said (3) is substantial.

When the transparent coloring layer satisfying the above relationship (3) is carried out and the production method of the present invention is carried out, for example, as shown in FIG. Since the other colored portions are formed in an unformed state, they do not run on the adjacent colored portion on the BM, while the G colored portion and the B colored portion formed between the R colored portion and the Y colored portion. Is formed on the hems of the already formed R colored part and Y colored part.
In other words, in the transparent colored layer formed by the photolithography method, the first colored portion is positioned evenly at the hem of the odd colored portion when the first colored portion is positioned first. The transparent colored layer in a relationship where the skirt of the colored portion is on the surface is shown in the manufacturing method of the present invention, “one colored portion is arbitrarily selected in a predetermined pattern in the colored portion formation scheduled area on the substrate. The colored portion formed first is the first colored portion, and then in the colored portion formation planned region where the colored portion is not yet formed, the predetermined pattern is formed on the basis of the colored portion formed first. By forming the transparent colored layer by forming the second and subsequent colored portions at odd positions in the row direction toward one direction or at positions adjacent to two already formed colored portions. It can be said that those formed.

  The above description does not mean that all the transparent colored layers in the color filter manufactured by the manufacturing method of the present invention have the relationship (3). Even if it is a transparent colored layer manufactured in the order of creation of the colored layer shown in the manufacturing method of the present invention, the transparent colored layer having the relationship (1) or (2) is prepared by adjusting the exposure method. Is possible. On the other hand, if the colored layer is not produced in the production order shown in the production method of the present invention, it is difficult to produce the transparent colored layer having the relationship (3).

  Hereinafter, the constituent layers of the color filter of the present invention will be described in more detail.

(About the board)
The substrate used in the present invention is preferably configured so as to be optically isotropic, and a glass substrate, a film having light transmissivity such as a film can be arbitrarily used. In particular, when the color filter of the present invention is used for a liquid crystal display, the substrate forming material is preferably alkali-free glass. The thickness of the substrate is, for example, about 5 μm to 3 mm depending on the application.

(About black matrix)
In the color filter of the present invention, when forming the BM, for example, a metal thin film having a light shielding property or a light absorbing property, such as a metal chromium thin film or a tungsten thin film, is formed on a substrate in a rectangular lattice shape or a stripe shape. Alternatively, it can be formed by patterning in a triangular lattice pattern or the like. Moreover, it is also possible to form by printing an organic material such as a black resin in a predetermined shape by a transfer method or the like.

  In the present invention, formation of BM is optional. However, even if alignment failure occurs in the critical region between the colored portions due to the presence of the BM, if the alignment failure region is within the BM region in plan view, transmission through the alignment failure region is attempted. Since light is blocked, it is preferable in that light leakage and coloring problems can be prevented from appearing on the display panel.

  The manufacturing method example of BM will be described in more detail. After the prepared black matrix material is washed on the glass substrate according to a conventional method, it is applied to a thickness of 3.0 μm by spin coating, at 90 ° C. for 3 minutes. Pre-baking, exposing a predetermined pattern (100 mJ / cm 2), spray development using 0.05% KOH aqueous solution for 60 seconds, followed by post-baking at 200 ° C. for 30 minutes to produce a black matrix substrate. it can. Further, the black matrix forming step may be performed by etching a substrate on which metal chromium or the like is vapor-deposited on a transparent substrate in advance. In the present invention, the BM formation method is not limited to the above, and whether or not the BM is provided in the present invention is arbitrary.

(About coloring part)
The colored portion in the present invention has a predetermined pattern by a photolithography method, directly or indirectly on a substrate, using a colored resist that transmits light of each color wavelength band for each of red, green, blue, yellow, and the like. Arranged and formed. As the arrangement form (patterning) of the colored portions, various arrangement patterns such as a stripe type, a mosaic type, and a triangle type can be selected. Hereinafter, the red, blue, green, and yellow colored portions will be described. However, in the present invention, a colored transparent colored portion other than these can be appropriately selected and formed.

<Red colored part>
Although the thickness of the red coating film formed as the red colored portion is different depending on the required color reproducibility and the composition of the red colored portion to be laminated, in general, the film thickness of the red colored portion is It is preferably in the range of 1 μm to 3 μm, and particularly preferably in the range of 1 μm to 2 μm. When the film thickness is thicker than the above range, for example, curing by photolithography method, patterning does not work, fine irregularities occur on the colored portion surface, or the shape becomes an inversely tapered shape, which is not preferable. If it is thinner than the range, it is difficult to obtain the required high color purity, which is not preferable.

The red colored portion formed in the present invention is generally composed of a red pigment, a yellow pigment, a binder, a dispersant, and other additives. Although the kind of binder changes with the manufacturing method of a red colored part, in this invention, it is preferable on the property of invention that a red colored part is formed by photolithography methods, such as a pigment dispersion method. Therefore, in the present invention, a UV curable resin is used as the binder resin.

As the red pigment, a red pigment generally used for a color filter can be used. Specifically, CI Pigment Red 9, CI Pigment Red 97, CI Pigment Red 122, CI Pigment Red 123, CI Pigment Red 149, CI Pigment Red 168, CI Pigment Red 177, CI Pigment Red 180, CI Pigment Red 192, CI Pigment Red 215, CI Pigment Red 216, CI Pigment Red v217, CI Pigment Red 220, CI Pigment Red 223, CI Pigment Red 223 224, CI Pigment Red 226, CI Pigment Red 227, CI Pigment Red 228, CI Pigment Red 240, Pigment Red 254, CI Pigment Red 48: 1, CI Pigment Orange 5, CI Pigment Orange 13, CI Pigment Orange 17, CI Pigment Orange 31, CI Pigment Orange 36, CI Pigment Oren 38, CI Pigment Orange 40, CI Pigment Orange 42, CI Pigment Orange 43, CI Pigment Orange 51, CI Pigment Orange 55, CI Pigment Orange 59, CI Pigment Orange 61, CI Pigment Orange 64, CI Pigment Orange 65, CI Pigment Orange One or more of 71 may be used in combination.
Among these, CI Pigment Red 177 and CI Pigment Red 254 are preferable, and CI Pigment Red 177 and CI Pigment Red 254 are preferably combined.

As the yellow pigment, a yellow pigment generally used for a color filter can be used. Specifically, CI Pigment Yellow 20, CI Pigment Yellow 24, CI Pigment Yellow 83, CI Pigment Yellow 86, CI Pigment Yellow 93, CI Pigment Yellow 109, CI Pigment Yellow 110, CI Pigment Yellow 117, CI Pigment Yellow 125, CI Pigment Yellow 137, CI Pigment Yellow 138, CI Pigment Yellow 139, CI Pigment Yellow 185, CI Pigment Yellow 147, CI Pigment Yellow 148, CI Pigment Yellow 150, CI Pigment Yellow 153, CI Pigment Yellow, CI Pigment Yellow 154, CI Pigment Yellow 166, CI Pigment Yellow 168, particularly preferably CI Pigment Yellow 83, CI Pigment Yellow 138, CI Pigment Yellow 139, C.I. Pigment Yellow 150.

In addition, the said pigment may use what was surface-treated, such as a rosin process, an acidic group process, a basic process, and a pigment derivative process, as needed. Further, as a dispersant necessary for dispersing the pigment, styrene / butyl styrene copolymer, long-chain polyaminoamide phosphate, polyamide, high molecular weight polycarboxylate, oleylamine acetate, tetraalkylammonium salt, oleic acid Sodium, oleic acid amino oleate, phosphate ester salt, alkylbenzene sulfonate, etc. can be mentioned. Such a dispersant can be contained in the range of 30 to 100 parts by weight with respect to 100 parts by weight of the pigment.

As the binder resin used together with such a red pigment and a yellow pigment, for example, a UV curable resin is used. As the UV curable resin, examples of the binder resin component include monomers having an acidic group such as (meth) acrylic acid, maleic anhydride, styrenesulfonic acid, styrene, α-methylstyrene, ethyl (meth) acrylate. And a copolymer obtained by copolymerizing a monomer such as (meth) acrylamide.

Moreover, you may add a photoinitiator as another additive, Specifically, a halomethylated triazine derivative, a halomethylated oxadiazole derivative, an imidazole derivative, a benzophenone derivative etc. are mentioned. These photopolymerization initiators are compounds capable of generating radicals that polymerize a polymerizable group of a photopolymerizable monomer with ultraviolet rays, and are used alone or in combination.
Furthermore, examples of the photopolymerizable monomer include isobutyl acrylate, t-butyl acrylate, stearyl acrylate, 2-methoxyethyl acrylate, and 3-methoxybutyl acrylate.

Specific examples of the solvent used for the coating for forming a red colored portion include diisopropyl ether, n-pentane, diethyl ether, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, methyl 3-ethoxypropionate, diglyme, An organic solvent such as butyl carbitol is exemplified.

In addition, various additives can be added to the red colored portion of the present embodiment as necessary, for example, a sensitizer, a coatability improver, a development improver, a crosslinking agent, a polymerization inhibitor, You may contain a plasticizer, a flame retardant, etc. In addition, about the addition of the various additives added to the said pigment, it is the same also about the other pigment mentioned later.

<Green coloring part>
Although the thickness of the green coating formed as the green colored portion is different depending on the required color reproducibility and the composition of the green colored portion to be laminated, in general, the thickness of the green colored portion is Usually, it is in the range of 1 μm to 3 μm, preferably in the range of 1 μm to 2 μm. The reason for this range is the same as the reason for the red colored portion, and a description thereof will be omitted here.

The green colored portion formed in the present invention is formed by applying a green colored portion forming paint, drying, pattern exposure and developing, like the above layer. The colored portion-forming paint is mainly composed of a binder resin such as a green pigment, a yellow pigment, and a UV curable resin, and a solvent.

As the green pigment, a green pigment generally used for a color filter can be used. Specifically, CI pigment green 7, CI pigment green 36, CI pigment green 47 are particularly preferable as the green pigment. Green 36 is listed.

Further, since the yellow pigment, binder resin, paint solvent, and other additives to be added are the same as those described in the above layer, the description thereof is omitted here.

<Blue coloring part>
Although the thickness of the green coating film formed as the blue colored portion differs depending on the required color reproducibility and the composition of the green colored portion to be laminated, generally, the film thickness of the green colored portion is Usually, it is in the range of 1 μm to 3 μm, preferably in the range of 1 μm to 2 μm. The reason for this range is the same as the reason for the red colored portion, and a description thereof will be omitted here.

  As the blue pigment, a blue pigment generally used for a color filter can be used. Specifically, as a blue pigment, a blue pigment generally used for a color filter can be used. CI pigment blue 15 (CI pigment blue 15: 1, CI pigment blue 15: 2, CI pigment blue 15: 3, CI pigment blue 15: 4, CI pigment blue 15: 5, CI pigment blue 15 : 6), CI pigment blue 21, CI pigment blue 22, CI pigment blue 60, CI pigment blue 64, particularly preferably CI pigment blue 15: 6.

Further, a purple pigment may be added to the blue colored portion in order to adjust the color tone. Specific examples of such purple pigments include CI pigment violet 19, CI pigment violet 23, CI pigment violet 29, CI pigment violet 32, CI pigment violet 33, CI pigment violet 36 and CI pigment violet 37. CI pigment violet 38, CI pigment violet 40, CI pigment violet 50, and CI pigment violet 23 are particularly preferable.
Further, the binder resin, the solvent for paint, and other additives to be added are the same as those described in the above layer, and thus the description thereof is omitted here.

<Yellow coloring part>
The film thickness of the yellow coating film formed as the yellow colored part is different depending on the required color reproducibility and the composition of the yellow colored part to be laminated, but in the present invention, the film thickness of the yellow colored part is Usually, it is in the range of 1 μm to 3 μm, preferably in the range of 1 μm to 2 μm. The reason for this range is the same as that for the other colored portions, and a description thereof is omitted here.

The yellow colored portion used in the present invention is formed by applying a paint for forming a yellow colored portion, drying, pattern exposure, and developing in the same manner as the above layer. The part-forming paint is mainly composed of a yellow pigment, a binder resin such as a UV curable resin, and a solvent. Since the yellow pigment, binder resin, paint solvent, and other additives to be added are the same as those described in the above layer, description thereof is omitted here.

<Others>
Cyan or magenta is known as a colored resist that constitutes a colored transparent colored portion other than red, green, blue, and yellow. As described above, other known colored portion resists can be appropriately used for constituting the colored portion in the present invention.

(About retardation layer)
The retardation layer 9 is made of a crosslinkable liquid crystal material, and is a layer for controlling the phase difference of light transmitted to the display. This control is desired for the crosslinkable liquid crystal material constituting the retardation layer 9. It is implement | achieved by making it fix in this oriented state by making it orientate in the direction of this, and carrying out a crosslinking polymerization mutually.

  The type of retardation layer that can be formed by designing the alignment direction of the crosslinkable liquid crystal material constituting the retardation layer 9 in a desired direction is to fix the liquid crystal molecules by vertical alignment (homeotropic alignment). By doing so, there is a so-called positive C plate in which the optical axis of the liquid crystal molecules faces the normal direction of the retardation layer and has an extraordinary ray refractive index larger than the ordinary ray refractive index in the normal direction of the retardation layer. . In another aspect, the retardation layer 9 has a so-called positive layer in which the optical axis of the liquid crystal molecules is parallel to the retardation layer and has an extraordinary ray refractive index larger than the ordinary ray refractive index in the in-plane direction of the retardation layer. A plate may be sufficient. Furthermore, by making the optical axis of the liquid crystal molecules parallel to the phase difference layer and adopting a cholesteric orientation having a spiral structure in the normal direction, the phase difference layer as a whole has an extraordinary ray refractive index smaller than the ordinary ray refractive index. It may be a so-called negative C plate that is in the normal direction of the retardation layer. Furthermore, the discotic liquid crystal having negative birefringence anisotropy may be a negative A plate having its optical axis in the in-plane direction of the retardation layer. Further, the retardation layer 9 may be a hybrid alignment plate that is inclined with respect to the layer or whose angle changes in a direction perpendicular to the layer.

  The retardation layer 9 may be a layer composed of any one of the positive C plate, the negative C plate, the positive A plate, and the hybrid alignment plate described above, but is formed by combining these layers. It may be a layer. For example, the retardation layer 9 may be configured by sequentially laminating a positive A plate and a positive C plate on the upper surface of the substrate 2. Alternatively, a positive A plate is first formed on the upper surface of the substrate 2, then a colored layer composed of a transparent colored portion and a light shielding region, which will be described later, is formed, and a positive C plate is further formed on the upper surface of the colored layer. May be. The C plate, negative C plate, positive A plate, and hybrid alignment plate that can be used as the retardation layer 9 can be appropriately formed on the transparent colored layer by a conventionally known method.

  Specifically, in order to form the retardation layer 9, first, a liquid crystal composition containing a crosslinkable liquid crystal material is applied onto a substrate to form a liquid crystal coating film. For the application of the liquid crystal composition, for example, gravure printing method, offset printing method, relief printing method, screen printing method, transfer printing method, electrostatic printing method, plateless printing method, gravure coating method, roll Coating methods such as coating methods, knife coating methods, air knife coating methods, bar coating methods, dip coating methods, kiss coating methods, spray coating methods, die coating methods, comma coating methods, ink jet methods, spin coating methods, slit coating methods, etc. Or a combination of these methods can be used as appropriate.

  Subsequently, the solvent component is removed by drying under reduced pressure, and the crosslinkable liquid crystal material contained in the liquid crystal coating film is oriented in a desired direction, and then irradiated with ultraviolet rays, electron beams, or the like, or irradiated with heat. A cross-linkable liquid crystal material oriented in the direction can be polymerized to form a retardation layer. However, the method of forming the retardation layer in the present invention is not limited to this, and is a conventionally known method in which the crosslinkable liquid crystal is polymerized and fixed on the substrate surface in a state of being oriented in a desired direction. Any method may be adopted as long as it can be used.

  For example, when the liquid crystal coating film is used as the retardation layer 9 having a function as a positive C plate, the crosslinkable liquid crystal materials are polymerized by homeotropic alignment of the crosslinkable liquid crystal material in the liquid crystal coating film. Giving homeotropic alignment to a crosslinkable liquid crystal material means that the liquid crystal coating film is heated by means of heating with infrared rays, etc., and the temperature of the liquid crystal coating film is changed so that the crosslinkable liquid crystal contained therein has a liquid crystal phase. The temperature (liquid crystal phase temperature) is equal to or higher than the temperature at which the crosslinkable liquid crystal becomes the isotropic phase (liquid phase).

In addition, polymerization (crosslinking polymerization) between crosslinkable liquid crystal materials provided with alignment in the liquid crystal coating film is to irradiate the surface of the liquid crystal coating film with light having a photosensitive wavelength of a photopolymerization initiator contained in the liquid crystal composition. You can proceed with. At this time, the wavelength of light applied to the liquid crystal coating film is appropriately selected according to the absorption wavelength of the liquid crystal composition, but is generally about 200 to 500 nm. The light applied to the liquid crystal coating film is not limited to monochromatic light, and may be light having a certain wavelength range including the photosensitive wavelength of the photopolymerization initiator. In addition, in making the liquid crystal coating film into the retardation layer 9, the liquid crystal coating film is irradiated with light to advance the crosslinking polymerization reaction of the crosslinkable liquid crystal material, and the liquid crystal coating film is further baked using an oven or the like. It may be done. By performing such firing, the polymerization reaction of the crosslinkable liquid crystal material contained in the retardation layer 9 can be promoted.
As described above, the crosslinkable liquid crystal material contained in the liquid crystal coating film is polymerized to form the retardation layer 9 fixed in a state where the crosslinkable liquid crystal material is oriented in a desired direction.

<Crosslinkable liquid crystal material>
As a liquid crystal material for constituting the retardation layer 9, a nematic liquid crystal having a rod-like structure is used as a liquid crystal material having positive birefringence anisotropy, and a liquid crystal material having negative birefringence anisotropy is used. A discotic liquid crystal having a disk-like structure can be used. These liquid crystal materials include liquid crystal monomers, liquid crystal oligomers, or liquid crystal polymers. In the present invention, these liquid crystal materials may be collectively referred to as liquid crystal molecules for convenience.

It is a polymerizable liquid crystal molecule, particularly a cross-linkable liquid crystal monomer, which is polymerized and cured by irradiation with ionizing radiation such as ultraviolet rays and electron beams in that it can be cured while maintaining the alignment state of the liquid crystal molecules. It is preferable to use one. Since retardation amount and alignment characteristics are determined by the birefringence Δn of the liquid crystal molecules and the thickness of the retardation layer, Δn is preferably about 0.03 to 0.15.

More specifically, the crosslinkable liquid crystal material contained in the liquid crystal composition used for forming the retardation layer has an unsaturated double bond in its molecular structure and is three-dimensional in the liquid crystal state. A polymerizable liquid crystal material capable of fixing the liquid crystal structure by crosslinking is considered. Here, as the polymerization type liquid crystal material, it is possible to use a compound included in (Chemical Formula 1) to (Chemical Formula 11) as shown in the general formula or a mixture of two or more of the following compounds. . In the case of the liquid crystalline monomer represented by the general chemical formula (Formula 11), X is preferably 4 to 6 (integer). Here, since the retardation amount and the alignment characteristics are determined by the birefringence Δn and the film thickness of the liquid crystal molecules, Δn is preferably about 0.03 to 0.20, more preferably about 0.05 to 0.15. The liquid crystal layer can be patterned by various printing methods or photolithography methods.
The polymerization type liquid crystal can be applied by dissolving in various organic solvents. The organic solvent is not particularly limited as long as the liquid crystal is dissolved, but it is preferable that the organic solvent can be uniformly applied on the substrate. If the substrate is water / oil repellant or if the added surfactant has strong water / oil repellency, UV cleaning and plasma treatment should be performed as long as the vertical alignment ability is not hindered. It is also possible to improve the performance.

（尚、Ｘは、４から６の整数である。）

(X is an integer from 4 to 6.)

  Moreover, it is preferable to mix | blend a photoinitiator in the said liquid crystal composition in the range which does not impair the alignment of a liquid crystal, and the radical polymerization initiator which generate | occur | produces a free radical by the energy of an ultraviolet-ray is preferable. The blending amount of the photopolymerization initiator is about 0.01% to 15% (mass basis), and more preferably about 0.5% to 10% (mass basis).

  Specific examples of the photopolymerization initiator include benzyl (also referred to as bibenzoyl), benzoin isobutyl ether, benzoin isopropyl ether, benzophenone, benzoylbenzoic acid, methyl benzoylbenzoate, 4-benzoyl-4'-methyldiphenyl sulfide, benzylmethyl Ketal, dimethylaminomethylbenzoate, 2-n-butoxyethyl-4-dimethylaminobenzoate, isoamyl p-dimethylaminobenzoate, 3,3'-dimethyl-4-methoxybenzophenone, methylobenzoyl formate, 2-methyl- 1- (4- (methylthio) phenyl) -2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butan-1-one, 1- (4 -Dodecylpheny ) -2-hydroxy-2-methylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1- (4-isopropylphenyl) -2 -Hydroxy-2-methylpropan-1-one, 2-chlorothioxanthone, 2,4-diethylthioxanthone 2,4-diisopropylthioxanthone, 2,4-dimethylthioxanthone, isopropylthioxanthone, 1-chloro-4-propoxythioxanthone, etc. Can be mentioned.

(About full-color liquid crystal display devices)
A liquid crystal display device 51 using the color filter 7 of the present invention will be described with reference to FIG.
FIG. 5 is a schematic cross-sectional view of a liquid crystal display device 51 including the color filter 7 of the present invention. As the liquid crystal display device 51, a so-called IPS driving method is exemplified, but other driving methods such as an MVA driving method and an OCB driving method may be used.

In the liquid crystal display device 51, the color filter 7 is incorporated as a substrate on one side as shown in FIG. 2E on the viewer side (upper side in FIG. 5) facing the viewer. The color filter 7 may further be provided with an alignment film for aligning the driving liquid crystal material in a desired direction on the upper surface (the driving liquid crystal layer side), but the alignment film is not shown. .
On the other hand, a liquid crystal driving substrate 71 in which a liquid crystal driving circuit 78 and a liquid crystal driving electrode 79 whose applied voltage is controlled thereby is provided on the driving liquid crystal layer 22 side is disposed on a backlight (not shown) side far from the observer. Has been. The liquid crystal drive electrode 79 is formed in a comb-like pattern for each pixel defined by the BM2.

  The driving liquid crystal layer 22 including the driving liquid crystal molecules 21 is enclosed in a sealed space surrounded by the retardation layer 14, the liquid crystal driving substrate 71, and the seal 18, and an applied voltage applied from the liquid crystal driving electrode 79 in the in-panel direction. As a result, the driving liquid crystal molecules 21 are switched. In order to secure a space for the driving liquid crystal layer 22, a plurality of columnar bodies are generally formed between the color filter 7 and the liquid crystal driving substrate 71, but this is not shown in FIG. To do.

  The liquid crystal display device 51 includes, in order from the observer side, a linearly polarizing plate 81, a retardation film 82 having an optical compensation function as a positive A plate, a retardation layer 14, a driving liquid crystal layer 22, a liquid crystal driving substrate 71, and linearly polarized light. A plate 83 and a backlight are arranged, and bright display and dark display are performed by controlling transmission or blocking of the backlight light for each picture element. Note that the linearly polarizing plate 81 and the linearly polarizing plate 83 are disposed so that the transmission axis directions are orthogonal to each other.

  Like the liquid crystal display device 51, according to the liquid crystal display device using the color filter of the present invention, the colored portions of four or more colors that are colored and transparent can display more complex colors in full color display, and In addition, there is no light leakage, and high-quality display with high contrast can be realized.

(Board adjustment)
A glass substrate (7059 glass manufactured by Corning Co., Ltd.) as a base material subjected to the cleaning treatment and a photoresist for colored portions of four colors of BM and red, green, blue and yellow were prepared. And the photoresist for coloring part was apply | coated to each color as shown below on the glass substrate upper surface, and the colored layer was laminated | stacked and formed on the base material. The composition of each photoresist will be described later.

(Coloring material adjustment)
A pigment-dispersed photoresist was used as a coloring material for BM and each region. The pigment-dispersed photoresist uses a pigment as a coloring material, adds beads to a dispersion composition (containing a pigment, a dispersant, and a solvent), disperses them with a disperser for 3 hours, and then removes the beads. And a clear resist composition (polymer, monomer, additive, disclosure agent and solvent). Its composition is shown below. A paint shaker was used as the disperser.

(Create BM)
First, the BM photoresist prepared above is applied to a glass substrate by spin coating, pre-baked (pre-baked) at 90 ° C. for 3 minutes, and exposed using a mask formed in a predetermined pattern ( 100 mJ / cm ² ), followed by spray development using a 0.05% KOH aqueous solution for 60 seconds, followed by post-baking (baking) at 200 ° C. for 30 minutes to form a BM having a thickness of 1.2 μm A base material (BM forming base material) was produced.

(Create transparent colored layer)
On the BM forming substrate, a pattern is designed so that a line having a width of 200 μm and a length of 4 cm becomes 100 rows × 1 column, and colored portions are repeatedly formed in order of red, green, yellow, and blue from the end. Each colored part was created as follows. It should be noted that, in relation to the BM, the design was made so that both ends of the above-mentioned line exist at positions where the BM is lifted.
First, a red (R) pigment-dispersed photoresist is applied on the surface of the BM-forming substrate by spin coating, pre-baked at 80 ° C. for 3 minutes, and then the position corresponding to the red colored portion ( Stripe pattern patterned so that a red colored portion is formed on the 4n-3rd line (where n is an integer greater than or equal to 1. The same shall apply hereinafter) with the first end of the picture element region as the first. The film was exposed to ultraviolet light (300 mJ / cm ² ) using a photomask for spraying, followed by spray development using a 0.1% KOH aqueous solution for 60 seconds, followed by post-baking (baking) at 200 ° C. for 60 minutes, and BM A pattern of a red (R) colored portion having a film thickness of 2.6 μm was formed at a predetermined position with respect to the pattern.

Subsequently, using a method similar to the method for forming the pattern of the red (R) colored portion, except that a patterned photomask on which the colored portion is formed is used 4n-1th, yellow (Y) coloring A department was created.
Thereafter, using a method similar to the method for forming the pattern of the red (R) colored portion except that a patterned photomask on which the colored portion is formed is used 4n-2nd, the green (G) colored portion It was created.
Finally, the blue (B) colored portion is created using the same method as the pattern forming method for the red (R) colored portion except that a patterned photomask on which the colored portion is formed is used 4nth. did.
In this way, a color filter in which a transparent colored layer constituted by repeatedly arranging BM and a red colored portion, a green colored portion, a yellow colored portion, and a blue colored portion in this order on a glass substrate was prepared. Was taken as Example 1.

<Photoresist for black matrix>
Black pigment: 14.0 parts by weight (TM Black # 95550 manufactured by Dainichi Seika Kogyo Co., Ltd.)
・ Dispersant: 1.2 parts by weight (Disperbyk 111 manufactured by Big Chemie Co., Ltd.)
・ Polymer 2.8 parts by weight (VR60 manufactured by Showa Polymer Co., Ltd.)
・ Monomer: 3.5 parts by weight (SR399, manufactured by Sartomer)
・ Additive: 0.7 parts by weight (L-20 manufactured by Soken Chemical Co., Ltd.)
Initiator: 1.6 parts by weight (2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1)
・ Initiator: 0.3 parts by weight (4,4'-diethylaminobenzophenone)
・ Initiator: 0.1 parts by weight (2,4-diethylthioxanthone)
・ Solvent: 75.8 parts by weight (ethylene glycol monobutyl ether)

<Red (R) colored portion photoresist>
・ Red pigment: 4.8 parts by weight (CIPR254 (Chromophthal DPP Red BP manufactured by Ciba Specialty Chemicals))
・ Yellow pigment: 1.2 parts by weight (CI PY139 (PASFOL Yellow D1819 manufactured by BASF))
・ Dispersant: 3.0 parts by weight (Solsparse 24000 manufactured by Zeneca)
-Monomer: 4.0 parts by weight (SR399 manufactured by Sartomer Co., Ltd.)
-Polymer 1 ... 5.0 parts by weight-Initiator ... 1.4 parts by weight (Irgacure 907 manufactured by Ciba Geigy)
・ 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)

<Green (G) Colored photoresist>
Green pigment: 3.7 parts by weight (CI PG7 (Seika Fast Green 5316P manufactured by Dainichi Seika))
・ Yellow pigment: 2.3 parts by weight (CI PY139 (PASFOL Yellow D1819 manufactured by BASF))
・ Dispersant: 3.0 parts by weight (Solsparse 24000 manufactured by Zeneca)
-Monomer: 4.0 parts by weight (SR399 manufactured by Sartomer Co., Ltd.)
-Polymer 1 ... 5.0 parts by weight-Initiator ... 1.4 parts by weight (Irgacure 907 manufactured by Ciba Geigy)
・ 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)

<Blue (B) Colored photoresist>
Blue pigment: 4.6 parts by weight (CI PB15: 6 (BASF Heliogen Blue L6700F))
・ Purple pigment: 1.4 parts by weight (CI PV23 (Clariant Foster Palm RL-NF))
・ Pigment derivative: 0.6 parts by weight (Solsperse 12000 manufactured by Zeneca)
・ Dispersant: 2.4 parts by weight (Solsparse 24000 manufactured by Zeneca Corporation)
-Monomer: 4.0 parts by weight (SR399 manufactured by Sartomer Co., Ltd.)
-Polymer 1 ... 5.0 parts by weight-Initiator ... 1.4 parts by weight (Irgacure 907 manufactured by Ciba Geigy)
・ 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)

<Yellow (Y) Colored photoresist>
・ Yellow pigment: 6.0 parts by weight (CI PY139 (PASFOL Yellow D1819 manufactured by BASF))
・ Dispersant: 3.0 parts by weight (Solsparse 24000 manufactured by Zeneca)
-Monomer: 4.0 parts by weight (SR399 manufactured by Sartomer Co., Ltd.)
-Polymer 1 ... 5.0 parts by weight-Initiator ... 1.4 parts by weight (Irgacure 907 manufactured by Ciba Geigy)
・ 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)

  In addition, the polymer 1 described in this specification is a copolymer 100 of benzyl methacrylate: styrene: acrylic acid: 2-hydroxyethyl methacrylate = 15.6: 37.0: 30.5: 16.9 (molar ratio). 2-Methacryloyloxyethyl isocyanate is added 16.9 mol% with respect to mol%, and the weight average molecular weight is 42500.

(Formation of retardation layer)
A retardation layer was formed on the upper surface of the transparent colored layer by the method described below.

<Formation of vertical alignment film>
First, in order to form a so-called positive C plate as a retardation layer on the transparent colored portion, a vertical alignment film was first formed.
Specifically, using JALS2021 (manufactured by JSR Co., Ltd.) as an alignment film material, patterning is performed on the above color filter by flexographic printing, and then baking is performed at 200 ° C. for 1 hour, thereby achieving a vertical alignment of 600 mm in thickness. A base substrate provided with a film was obtained. In this case, a protective layer made of a transparent resin may be provided between the colored layer and the alignment film. This is because the step of the color filter is relaxed and more reliable liquid crystal alignment is possible.

<Preparation of Liquid Crystal Composition Containing Crosslinkable Liquid Crystal Material>
A liquid crystal composition containing a crosslinkable liquid crystal material constituting the retardation layer was prepared as follows.
As a polymerizable liquid crystalline monomer molecule showing a nematic liquid crystal layer, 20 parts by weight of a compound represented by (Chemical Formula 11) (where X is 6) and a photopolymerization initiator (“Irgacure 907” manufactured by Ciba Geigy Co., Ltd.) ) 0.8 parts by weight, 59.2 parts by weight of chlorobenzene as a solvent, and 20 parts by weight of a solution obtained by diluting the vertical alignment film forming solution JALS-2021-R2 with diethylene glycol dimethyl ether to 12.5%, A liquid crystal composition was prepared.

<Formation of retardation layer>
Next, the prepared liquid crystal composition was placed on a spin coater (manufactured by MIKASA, “trade name 1H-360S”), and the liquid crystal composition prepared in advance was dried. The upper surface of the alignment film was spin-coated so that the subsequent film thickness was about 1.5 μm. In this embodiment, the spin coating method is applied. However, the present invention is not limited to this as long as it can be uniformly applied on the substrate, and may be die coating, slit coating, or a combination thereof. There is no particular limitation.
Subsequently, the substrate is heated on a hot plate at 100 ° C. for 3 minutes to remove the residual solvent and align the liquid crystalline monomer contained in the liquid crystal solution in the vertical direction, and the film formed by the liquid crystal solution is white. The alignment of the liquid crystal molecules was confirmed by visually confirming the liquid crystal transition point that became transparent. Subsequently, under a nitrogen atmosphere, the entire surface of the liquid crystal coating film is irradiated with ultraviolet rays (20 mW / cm ² , 365 nm, 10 nm) using an ultraviolet irradiation device (“TOSCURE 751” manufactured by Harrison Toshiba Lighting Co., Ltd.) having an ultrahigh pressure mercury lamp. Second), the crosslinkable liquid crystalline molecules constituting the liquid crystal layer were three-dimensionally crosslinked and cured. A curing reaction was completed by heating and baking on a 230 ° C. hot plate for 60 minutes, and a retardation layer of a positive C plate having a thickness of 1.45 μm was obtained.

(Comparative example)
Patterning in which the colored portion is formed 4n-2 after the red colored portion is formed 4n-3 so that the colored portion is repeatedly formed in the order of red, green, yellow, and blue to form a transparent colored layer. The green colored part is formed using the photomask formed, then the yellow colored part is formed using the patterned photomask in which the colored part is formed 4n-1 and finally the colored part is formed 4nth. A color filter was prepared in the same manner as in Example 1 except that a blue colored portion was formed using a patterned photomask to be used as Comparative Example 1.

(Evaluation 1) Light Leakage Evaluation In order to evaluate the performance of whether or not light leakage is prevented when light is transmitted through the color filter, light leakage of Example 1 was evaluated by the following method.

  In the state which applied the light of the sample of Example 1 created as mentioned above in the state which set the polarization microscope CPX31-P by Olympus Co., Ltd. to the cross Nicol state, and sandwiched the color filter of Example 1 on the polarizing plate. The substrate was rotated and the presence or absence of light leakage was observed with the naked eye. As a result, no light leakage was observed in the entire region of Example 1.

For Comparative Example 1, a sample was formed in the same manner as in Example 1, and then light leakage was evaluated. As a result, light leakage was confirmed at the green colored portion and the yellow colored portion.

(Evaluation 2) Measurement of front luminance The front luminance was measured using a luminance measurement system constructed with a luminance measuring device, a color filter with a retardation layer, a polarizing plate, and a light irradiation unit that emits light.

  In the luminance measurement system, the luminance measuring device detects light that has passed through the color filter with a retardation layer sandwiched in a polarizing plate crossed Nicol state among the light emitted from the light irradiation unit, and the light sensor detects And a measuring unit that measures the luminance based on the received signal. Specifically, “BM-9” manufactured by Topcon Corporation was used as a luminance measuring device for measuring luminance.

  Using the above luminance measurement system, the front luminance was measured as follows. First, a color filter with a retardation layer is arranged with two polarizing plates sandwiched in a crossed Nicol state, a light irradiation part is arranged outside the first polarizing plate, and a liquid crystal is sandwiched with a color filter with a retardation layer. An optical sensor was disposed at a position facing the thickness direction of the layer and outside the second polarizing plate.

Next, light is irradiated from the light irradiation unit toward the liquid crystal display device, and the light that has passed through the cell from the position outside the second polarizing plate and passed through the first polarizing plate is detected by the optical sensor. The amount of brightness (luminance) was measured by the measurement unit, and the front luminance was measured. As a result of the above measurement, the front luminance of Example 1 was 0.21 cd / m ² .

Also in Comparative Example 1, as in Example 1, front luminance was measured according to the above evaluation 2. As a result, the front luminance of Comparative Example 1 was 0.41 cd / m ² .

  From the results of the above evaluations 1 and 2, the color filter of the present invention does not cause light leakage when transmitting light. For example, when used as a substrate on one side of a liquid crystal display, a high-quality image is obtained. It is possible to provide. Further, it was also confirmed by the front luminance of evaluation 2 that there was no light leakage in the color filter of the present invention.

It is a top view of the transparent colored layer in the color filter of this invention. 2A to 2E are schematic side views of the substrate in each step for explaining the steps of the color filter manufacturing method of the present invention. It is the cross-sectional schematic of the color filter of this invention. It is a section schematic diagram of a transparent colored layer in a color filter of the present invention. 1 is a schematic cross-sectional view of a liquid crystal display device of the present invention. It is a top view of the transparent colored layer in the conventional color filter. It is a cross-sectional schematic diagram of a conventional color filter.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Glass substrate 2 Black matrix 3 Red colored part 4 Yellow colored part 5 Green colored part 6 Blue colored part 7 Color filter 8 Transparent colored layer 9 Phase difference layer 14 Phase difference layer 21 Drive liquid crystal molecule 22 Drive liquid crystal layer

Claims (9)

A transparent colored layer composed of at least an even number and four or more colored portions directly or indirectly on a substrate, and a retardation layer in which a crosslinkable liquid crystal material is fixed in a desired direction. A color filter provided in this order,
The colored portions are arranged in a predetermined pattern in order with at least one direction as a repeating direction, and a cross-sectional outer shell in a vertical section in which the colored portions are cut in the repeating direction is substantially biased in one direction. A color filter characterized by being not inclined. The color filter according to claim 1, wherein the outer shells of the colored portions are substantially symmetrical. 3. The color filter according to claim 1, wherein a substantially flat outer shell portion exists in a lateral direction from a central portion of the cross-section outer shell of each colored portion. The color filter according to any one of claims 1 to 3, wherein a black matrix layer is provided on the substrate and below the transparent colored layer. From the electrode part which faces two substrates, provides a driving liquid crystal layer in a space formed between the substrates, and changes the orientation of driving liquid crystal molecules filled in the driving liquid crystal layer by applying a voltage. The color filter according to any one of claims 1 to 4 is used as one substrate in a multi-layered liquid crystal display device in which a polarizing plate is laminated on the outside of the two substrates. A liquid crystal display device. A method for producing a color filter comprising a transparent colored layer composed of even and four or more colored portions arranged in a predetermined pattern in order with at least one direction as a repeating direction, directly or indirectly on a substrate. , By using a photolithographic method, a colored portion of one color is formed at a position where the colored portion is to be formed on the substrate at an arbitrarily selected position in a predetermined pattern, and this first formed colored portion is the first, In a colored portion formation scheduled area where no colored portion is formed, the odd numbered position toward one direction of the predetermined pattern or two already formed colored portions with respect to the first formed colored portion as a reference The transparent colored layer is formed by forming a colored portion for the second and subsequent colors at a matching position, and then the crosslinkable liquid crystal is directly or indirectly formed on the transparent colored layer. A liquid crystal composition containing a coating material is applied to form a coating film, the crosslinkable liquid crystal material present in the coating film is oriented in a desired direction, and then the coating film is irradiated with light and / or heat. The method for producing a color filter according to any one of claims 1 to 4, wherein the retardation layer is formed by cross-linking and fixing the cross-linkable liquid crystal material in an aligned state. The method for producing a color filter according to claim 6, wherein a pattern in which the colored portions constituting the transparent colored layer are arranged is in a stripe shape. The formation position of the first color of the colored striped pattern is a colored portion corresponding to the extreme end of the effective display region, or an odd number of colored portions including the colored portion corresponding to the extreme end of the effective display region. The method for producing a color filter according to claim 7, wherein: The method for producing a color filter according to claim 6, wherein the pattern in which the colored portions constituting the transparent colored layer are arranged is a matrix.

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