JP2010250121A - Method of manufacturing color filter, and liquid crystal display device having color filter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a color filter having a phase difference layer formed at a planned line width. <P>SOLUTION: The method of manufacturing the color filter includes a color filter layer-forming step of disposing a plurality of colored layers 5, 6 and 7 directly or indirectly on a base material 2, and a phase difference layer-forming step of forming the phase difference layer 9 in a linear pattern at a predetermined position. The phase difference layer-forming step includes a first step of applying liquid crystal composition containing liquid crystal compound containing a polymerizable functional group and aligning the liquid crystal compound in a predetermined direction, and a second step of radiating active radiation to a liquid crystal-coated film via a halftone mask having an opening of a predetermined pattern and polymerizing the liquid crystal compound. The halftone mask of the second step has the opening at a position determined according to the forming position of the linear phase difference layer. The line width of a part with low light transmittance in the opening is larger than that of a part with high light transmittance in the opening. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a color filter manufacturing method and a liquid crystal display device including the color filter.

  Color display liquid crystal display devices (color liquid crystal display devices) have the advantages of being thin and light and have low power consumption. In various industrial fields, TVs, computers, mobile phones, electronic notebooks, various terminal devices, and vending machines Used for display devices such as images and video.

  The color liquid crystal display device has a structure (liquid crystal cell) including a substrate facing each other and a driving liquid crystal layer in which liquid crystal is sealed between the substrates. In addition, a color filter layer including a colored layer is provided on one of the substrates constituting the liquid crystal cell. As the colored layer constituting the color filter layer, for example, various colored layers such as a red colored layer (R), a green colored layer (G), and a blue colored layer (B) are known. .

  Liquid crystal display devices have been widely used especially in mobile device applications, and as a result, there has been a demand for further thinning, power saving, and display of liquid crystal images that are easy to see in any environment (ambient brightness). ing. In order to meet this problem, a transflective liquid crystal display device having a transmissive display function and a reflective display function has been proposed.

  As an excellent transflective liquid crystal display device, there has been proposed a liquid crystal display device in which a retardation layer is formed in a reflective portion determined in accordance with a reflective display function. As the retardation layer, one having a “structure obtained by aligning and polymerizing a polymerizable liquid crystal compound having a polymerizable functional group in a predetermined direction” is known.

  However, in general, the polymerizable liquid crystal compound constituting the retardation layer has a wavelength dispersion characteristic of the refractive index, and the refractive index anisotropy of the polymerizable liquid crystal compound increases on the short wavelength side. On the other hand, when the retardation layer is formed in a predetermined portion of the color liquid crystal display device, the actually required wavelength dispersion characteristic is such that the refractive index anisotropy is increased on the long wavelength side. Therefore, in the color liquid crystal display device in which the retardation layer is formed, the wavelength dispersion characteristic of the retardation layer becomes a problem.

  Regarding this problem, a color filter in which the retardation of the retardation layer is changed according to the color type of the colored layer has been proposed (Patent Document 1).

JP 2008-1116731 A

  In the color filter described in Patent Document 1, the retardation layer is obtained by applying a liquid crystal composition liquid containing a polymerizable liquid crystal compound having a polymerizable functional group to a substrate to obtain a coating film and curing the coating film. And formed. Curing of the coating film is performed by irradiating the coating film with actinic radiation such as ultraviolet rays from a predetermined actinic radiation source to cause a polymerization reaction of the polymerizable liquid crystal compound contained in the coating film. At this time, actinic radiation is irradiated toward the coating film through a halftone mask on which a predetermined mask pattern is formed, and a retardation layer having a predetermined pattern corresponding to the mask pattern is formed. In this color filter, the retardation layer gives a partially different phase difference to the incident light flux. That is, a phase difference given to a light beam passing through a colored layer of a predetermined color type out of an incident light beam and a phase difference given to a light beam passing through a colored layer of a color type different from that color type are different from each other. Yes.

  By the way, in order to obtain a color filter that can be used by being incorporated in a transflective liquid crystal display device, the phase difference layer of the color filter has a portion corresponding to the reflective portion while avoiding a portion corresponding to the transmissive portion. Often patterned linearly. Then, among the color filters described in Patent Document 1, what can be used by being incorporated in a transflective liquid crystal display device, the phase difference layer of the color filter is formed in a linear shape and incident light flux. Therefore, it has a part that gives a relatively high phase difference and a part that gives a low phase difference. However, when forming the retardation layer with the color filter described in Patent Document 1, the dose of active radiation applied to the coating film is higher in the portion corresponding to the portion having a higher phase difference in the coating film. More than the part corresponding to the low part. For this reason, in the color filter described in Patent Document 1, the portion of the coating film corresponding to the portion having a high phase difference is more likely to cure the coating film in a wider range than the portion corresponding to the portion having a low phase difference. One of the high phase difference portion and the low phase difference portion has a value deviated from the expected line width, and the retardation layer may be formed in an irregular line width. As a method for solving the problem due to this, a method is conceivable in which a portion having the smallest width in the retardation layer is determined and a portion having a larger width than that portion is shielded by a black matrix. However, in such a method, the portion of the retardation layer that can exhibit the optical function is greatly limited, and the retardation layer cannot be effectively used.

  Actually, in a color transflective liquid crystal display device, the reflective part is often used as an auxiliary, and in this case, the line width of the retardation layer is set to about 10 μm to 50 μm, and the line is averaged. The width is often set to about 30 μm. Furthermore, in a transflective liquid crystal display device, the boundary between the reflective part and the transmissive part is often partitioned by a black matrix in plan view. In that case, both side edges of the retardation layer are in plan view. A black matrix is formed along the longitudinal direction of the linear retardation layer so as to be hidden by the black matrix. And even if the black matrix is formed thin, it is usually about 5 μm in width and about 10 μm in width. Then, in a color transflective liquid crystal display device, a portion where the retardation layer can exhibit a function of causing a phase difference in an incident light beam is usually about 20 μm wide when a side of 5 μm on one side of the retardation layer is shielded with a black matrix. It will be part of. By the way, when the color types of the color layers constituting the color filter layer are three colors of RGB, the line width of the retardation layer is approximately 1 μm at each portion of the retardation layer facing each pixel of RGB. In many cases, the difference between the line width deviated from the planned line width and the thin line width portion and the thick portion becomes about 2 μm. At this time, if it is intended to eliminate the distorted line width of the retardation layer by the black matrix as described above, it is necessary to make the width of the black matrix larger than the planned width. As a result, the portion of the retardation layer that can exhibit the optical function is reduced by 10%, and the retardation layer cannot be used effectively. Of course, a configuration in which a black matrix is not disposed at both ends of the retardation layer is also conceivable, but even in that case, it is desirable that the line widths of the retardation layer be uniform so that RGB balance (white balance) can be achieved.

  In view of the above problems, the present invention provides a color filter having a retardation layer, in which the retardation layer gives a partially different phase difference to the incident light flux and is formed in a predetermined shape pattern. An object of the present invention is to provide a method for producing a color filter having a retardation layer formed with a predetermined line width, and to provide a liquid crystal display device having a color filter having such a retardation layer. With the goal.

The present invention includes (1) a light-transmitting base material, a color filter layer having a plurality of colored layers and provided directly or indirectly to the base material, and a partially different position with respect to incident light flux. A method for producing a color filter comprising a phase difference layer and a phase difference layer provided in a linear pattern at a predetermined position directly or indirectly with respect to a substrate,
A color filter layer forming step of providing a plurality of colored layers directly or indirectly on the substrate;
A retardation layer forming step of forming a retardation layer in a linear pattern at a predetermined position directly or indirectly with respect to the substrate, and
In the retardation layer forming step, a liquid crystal composition containing a liquid crystal compound having a polymerizable functional group is applied directly or indirectly to a substrate to form a liquid crystal coating film, and the liquid crystal contained in the liquid crystal coating film A liquid crystal compound contained in the liquid crystal coating film is polymerized by irradiating the liquid crystal coating film with actinic radiation through a first step of aligning the compound in a predetermined direction and a halftone mask having openings of a predetermined pattern. A second stage,
In the halftone mask used in the second stage, an opening is formed at a position determined according to the formation position of the linear retardation layer, and the opening has a difference in phase difference given to the incident light beam. Each of the predetermined portions corresponding to the portion of the retardation layer divided based on the light transmittance, and the opening portion is larger than the line width of the portion where the light transmittance is high in the opening portion. A method for producing a color filter, characterized in that the line width of the portion having a low light transmittance in is made larger.
(2) The method for producing a color filter according to (1), wherein the retardation layer forming step is performed after the color filter layer forming step,
(3) The method for producing a color filter according to (1), wherein the color filter layer forming step is performed after the retardation layer forming step.
(4) A transmissive portion that is used in a transflective display device having both transmissive and reflective liquid crystal display functions, and is defined corresponding to a portion that exhibits the transmissive liquid crystal display function, and a reflective type A method of manufacturing a color filter comprising a reflective portion defined corresponding to a portion that exhibits the liquid crystal display function of
In the phase difference layer forming step, the phase difference layer is patterned so as to avoid the transmission portion and cover the reflection portion, the method for producing a color filter according to any one of (1) to (3) above,
(5) A liquid crystal display device including a liquid crystal cell in which liquid crystal is sealed between a pair of facing substrates,
A liquid crystal display device in which a color filter obtained by the manufacturing method according to any one of (1) to (4) is incorporated as one of substrates constituting a liquid crystal cell;
Is the gist.

  According to the present invention, when a linear phase difference layer that gives a partially different phase difference to an incident light beam is formed, a halftone mask having an opening whose line width is adjusted is used. . At this time, the line width of the opening of the halftone mask is adjusted according to the portion of the retardation layer that is partitioned based on the difference in the phase difference applied to the incident light beam. As a result, in the plan view of the retardation layer, at least one of the region where the retardation layer of the retardation layer is high and the region where the retardation layer of the retardation layer is low is likely to be out of the expected line width. The conventional problem that it has become difficult to form a retardation layer having a line width of 2 mm can be effectively suppressed.

(A) It is a top view for demonstrating the state in which the phase difference layer was formed in the 1st Embodiment of this invention. (B) In the 1st Embodiment of this invention, it is a coating film. It is a cross-sectional schematic diagram for demonstrating the process of irradiating actinic radiation toward the direction, (c) It is a cross-sectional schematic diagram which shows typically the AA line cross section of Fig.1 (a). In the 2nd Embodiment of this invention, it is a cross-sectional schematic diagram for demonstrating typically the state in which the colored layer was formed on the phase difference layer. (A) It is a top view for demonstrating the state of the color filter manufactured in the 3rd Embodiment of this invention typically, (b) The BB sectional view of FIG. 3 (a) is typical. It is a cross-sectional schematic diagram shown. It is a perspective schematic diagram for demonstrating typically the structure of the transflective liquid crystal display device incorporating the color filter manufactured by this invention. It is a plane schematic diagram for demonstrating typically the example of the mask pattern of a halftone mask. It is a plane schematic diagram for demonstrating the formation pattern of the colored layer in an Example.

  In the present invention, as shown in FIGS. 1 (a) and 1 (c), a light-transmitting substrate 2 and a plurality of colored layers 5, 6, and 7 are provided directly or indirectly on the substrate 2. And a retardation layer 9 provided directly or indirectly with respect to the color filter layer 3.

  Here, the phase difference layer 9 shows a layer structure that gives a partially different phase difference to an incident light beam incident on the phase difference layer 9, and this is based on a plan view of the phase difference layer 9. On the surface of the material 2, it is formed in a line at a predetermined position. In this specification, “providing a partially different phase difference with respect to an incident light beam” means that a predetermined region (region A, region B) that does not overlap each other in a plan view of the retardation layer 9 is selected. In addition, the phase difference given to the portion of the incident light beam that has passed through the region A of the phase difference layer 9 in the thickness direction of the phase difference layer 9 and the phase difference given to the portion of the light beam that has passed through the region B are Indicates different from each other. The phase difference layer 9 is divided into predetermined portions based on the value of the phase difference given to the incident light beam. That is, in a plan view of the phase difference layer 9, “a portion where the phase difference given to the incident light beam has a certain value (Na)” or “a value that has a phase difference given to the incident light beam (Nb). The “parts such as” can be divided into regions. In the phase difference layer 9, the portion divided based on the value of the phase difference (regionally divided portion (partitioned region)) forms a portion specified by one grouped region, a strip shape or a matrix An area group formed by forming a predetermined pattern such as a shape may be used.

[First Embodiment]
A specific embodiment of the method for manufacturing the color filter 1 according to the present invention will be described (first embodiment) (FIGS. 1A, 1B, and 1C).

  This color filter manufacturing method includes a color filter layer forming step and a retardation layer forming step, and the color filter layer forming step is performed before the retardation layer forming step.

(Color filter layer formation process)
In the color filter layer forming step, which is a step of forming the color filter layer, the colored layers 5, 6, and 7 that allow visible light of a predetermined range of incident light to pass through are directly or indirectly provided on the substrate 2. It is realized by. At this time, the colored layers 5, 6, and 7 are provided so as to have thicknesses (film thicknesses) set as appropriate. In the example of FIG. 1, the color filter layer 3 is provided directly on the base material 2.

  Therefore, first, the base material 2 is prepared. The base material 2 may be a single layer or a single layer or a composite material composed of a plurality of types of multilayers.

  The substrate 2 is preferably configured so as to be optically isotropic. As the base material 2, a plate-like body made of various materials such as a glass substrate and a plastic substrate can be appropriately selected.

  On the surface of the prepared base material 2, a region where the colored layers 5, 6, and 7 of a predetermined color are scheduled to be formed is determined. The portion designated in the region forms the colored layer formation scheduled portions N1, N2, and N3 (FIG. 1B). FIG. 1B shows an example of the color filter in which the color filter layer 3 is formed by providing the color layers 5, 6, and 7 on the color layer formation scheduled portions N 1, N 2, and N 3 of the substrate 2. It is a cross-sectional schematic diagram for demonstrating.

  Colored layers 5, 6, and 7 of predetermined colors corresponding to the respective colored layer formation scheduled portions N1, N2, and N3 of the base material 2 are formed. Regions defined by the colored layer formation scheduled portions N1, N2, and N3 of the substrate 2 are covered with the colored layers 5, 6, and 7, respectively.

  The colored layers 5, 6, and 7 of the predetermined colors have different color types. Note that different color types in this specification indicate that the wavelength that maximizes the transmittance of light in the visible light region (having a wavelength of 400 nm to 700 nm) differs by 10 nm or more.

  In the example of FIG. 1, the colored layer formation scheduled portions N1, N2, and N3 are formed in a strip shape, and the colored layers 5, 6, and 7 of three colors (red (R), green (G), and blue (B)) are formed. However, the color filter layer 3 is formed by these colored layers 5, 6, 7 being arranged in a strip shape according to the colored layer formation scheduled portions N 1, N 2, N 3.

  The colored layers 5, 6, and 7 are formed by a photolithography method as described below, or a printing method or the like.

<When a colored layer is formed by photolithography>
First, for each color type of the colored layers 5, 6, and 7, a color material dispersion liquid in which a color material formed by blending a pigment corresponding to each color type and a resin material such as a photocurable resin is dispersed in a solvent. Is prepared. A colored material dispersion prepared corresponding to the colored layer 5 is applied to the substrate 2 to form one side of the coating film. And after irradiating the coating film with light of a predetermined wavelength through a photomask in which a pattern is formed in a predetermined shape corresponding to the predetermined colored layer formation scheduled portion N1 in the base material 2, development processing is performed, 2, the colored layer 5 can be formed. As for the colored layers 6 and 7, the same method as the method for forming the colored layer 5 is applied except that the coloring material dispersion and the photomask pattern are different, so that the base material 2 is colored. Layers 6 and 7 can be formed.

  In the color filter layer forming step, as shown in FIG. 1, the colored layers 5, 6, and 7 are formed for each color type on the flat substrate 2 surface.

  The colored layers 5, 6, and 7 of each color have a light-transmitting property with respect to visible light having a predetermined wavelength, and the incident visible light is dispersed to obtain red (R), green (G), and blue (B ) And light. At this time, the RGB three-color colored layers (red (R) colored layer 5, green (G) colored layer 6, blue (B) colored layer 7) are divided into fine sections for each predetermined region. Thus, one section forms one pixel. In addition, one picture element is formed by the three pixels defined by the three color layers of RGB arranged in the frame order.

  The color filter layer 3 may be composed of three color layers 5, 6 and 7 of the RGB system, or may be composed of three color layers of the CMY system which are complementary colors. Alternatively, it may be composed of four or more colored layers. In addition to the strip shape, the colored layer may have an appropriate shape such as a rectangular shape or a triangular shape.

(Retardation layer forming process)
The retardation layer forming step is a step of forming the retardation layer 9 directly or indirectly with respect to the substrate 2. The retardation layer 9 formed in the retardation layer forming step is formed with a structure in which a liquid crystal compound is polymerized.

  In the example of the color filter 1 in FIGS. 1A and 1C, the retardation layer forming step is performed after the color filter layer forming step, and the retardation layer 9 is the color filter layer 3 with respect to the substrate 2. It is formed indirectly via.

  The phase difference layer forming step includes forming a liquid crystal coating film 4 directly or indirectly on the substrate 2 and aligning the liquid crystal compound contained in the liquid crystal coating film 4 in a predetermined direction (first stage), liquid crystal A step of curing the liquid crystal coating film 4 while aligning the liquid crystal compound contained in the coating film 4 in a predetermined direction and a (second stage) (FIG. 1B) are provided.

  By the way, before the first stage is performed, the alignment film is formed on the base material 2 according to the necessity of laying the alignment film. Then, the first stage is performed, and the liquid crystal coating film 4 is formed on the alignment film. At this time, as the alignment film, a vertical alignment film or a horizontal alignment film is selected according to the alignment (for example, horizontal alignment, vertical alignment) required for the liquid crystal compound included in the retardation layer 9.

  When a horizontal alignment film is selected as the alignment film, first, a coating film is prepared by applying directly or indirectly to a substrate using a material such as polyimide that can be used for the alignment film. For example, in the example of FIG. 1, the coating film is formed so that the color filter layer surface is covered with the coating film. As a method for forming the coating film, a conventionally known method (printing method, spin coating method, etc.) is appropriately employed. When the coating film is produced, the coating film is subjected to a rubbing process, and the coating film forms a horizontal alignment film.

<First stage>
In forming the liquid crystal coating film 4, a liquid crystal composition is prepared. The liquid crystal composition includes a liquid crystal compound and a solvent.

  The liquid crystal composition is selected according to the required optical function of the retardation layer 9 and the type and orientation of the selected liquid crystal compound. As the liquid crystal compound, a liquid crystal compound capable of forming a nematic liquid crystal phase or a liquid crystal compound capable of forming a smectic liquid crystal phase can be used. Examples of such a liquid crystal compound include a liquid crystal compound having a rod-like molecular shape and a liquid crystal compound having a disc-like molecular shape, and a liquid crystal compound having a rod-like molecular shape is preferable.

  The liquid crystal compound is preferably a polymerizable liquid crystal compound having an unsaturated double bond as a polymerizable functional group in the molecular structure forming the liquid crystal compound. The polymerizable liquid crystal compound is more preferably a polymerizable liquid crystal compound capable of undergoing a crosslinking polymerization reaction in a liquid crystal phase (also referred to as a crosslinked polymerizable liquid crystal compound or a crosslinkable liquid crystal compound). Those having an unsaturated double bond at both ends of the molecular structure (having two or more unsaturated double bonds) are preferred. By forming the retardation layer 9 using a polymerizable liquid crystal compound, a crosslinked polymer structure in which molecules forming the polymerizable liquid crystal compound are mutually crosslinked can be formed in the retardation layer 9.

  Specific examples of the polymerizable liquid crystal compound include nematic liquid crystal compounds having a polymerizable functional group (polymerizable nematic liquid crystal molecules). Examples of the polymerizable nematic liquid crystal compound include monomers, oligomers, and polymers having at least one polymerizable group such as (meth) acryloyl group, epoxy group, octacene group, and isocyanate group in one molecule. As such a polymerizable liquid crystal compound, more specifically, as the polymerizable liquid crystal monomer, compounds represented by the following formulas (1) to (11) can be given.

・・・（１）

... (1)

・・・（２）

... (2)

・・・（３）

... (3)

・・・（４）

... (4)

・・・（５）

... (5)

・・・（６）

... (6)

・・・（７）

... (7)

・・・（８）

... (8)

・・・（９）

... (9)

・・・（１０）

... (10)

・・・（１１）

上記の式（１１）中、メチレン基の数（アルキレン基の鎖長）を示すａ〜ｂはいずれも整数であって、ａ、ｂが、各々個別に２〜１２であり、より好ましくは３〜１０、特に好ましくは４〜８である。

(11)

In the above formula (11), a to b indicating the number of methylene groups (chain length of the alkylene group) are all integers, and a and b are each 2 to 12, more preferably 3 -10, particularly preferably 4-8.

  The amount of the liquid crystal compound contained in the liquid crystal composition varies depending on the desired film thickness of the retardation layer 9, the magnitude of the desired retardation, and the like, but is usually 10% to 40% by weight with respect to the liquid crystal composition. %.

  The solvent can dissolve the liquid crystal compound and the like and inhibits the alignment performance of such a material when a “material that imparts alignment to the liquid crystal compound” such as an alignment film is provided on the substrate 2. If it does not, it will not specifically limit. Specific examples of the solvent include hydrocarbons such as toluene, ketones such as methyl ethyl ketone, amide solvents such as N-methyl-2-pyrrolidone, and glycol solvents such as diethylene glycol dimethyl ether.

  The liquid crystal composition contains a photopolymerization initiator such as Irgacure 184, Irgacure 369, Irgacure 651, Irgacure 907 (all manufactured by Ciba Specialty Chemicals), Darocur (Merck). It is preferable that Further, the liquid crystal composition may contain a surfactant serving as an auxiliary agent that improves the coating properties. When the liquid crystal molecules contained in the retardation layer 9 are twisted and aligned according to the optical function of the retardation layer 9 and the type and orientation of the selected liquid crystal compound, the liquid crystal composition includes S A chiral agent such as −811 may be included as appropriate.

  When a liquid crystal compound having a polymerizable functional group (polymerizable liquid crystal compound) is selected and a liquid crystal composition containing the same is prepared, the liquid crystal composition is applied directly or indirectly to the substrate 2. Thereby, the liquid crystal coating film 4 is formed (FIG. 1B), where the liquid crystal coating film 4 is formed on the surface of the color filter layer 3 in FIG.

  Examples of the method for applying the liquid crystal composition include spin coating, roll coating, slide coating, printing, and die coating.

  The liquid crystal coating film is preferably pre-baked between the first stage and the second stage (pre-baking treatment). In this pre-baking treatment, the liquid crystal compound contained in the liquid crystal coating film 4 is more effectively brought into a predetermined alignment state, and the solvent contained in the liquid crystal coating film 4 is removed. The pre-baking temperature and time may vary depending on the characteristics of the polymerizable liquid crystal compound contained in the liquid crystal composition, but are usually 70 ° C. to 120 ° C. for several minutes to 30 minutes.

<Second stage>
When the polymerizable liquid crystal compound contained in the liquid crystal coating film 4 is aligned in a predetermined direction, the active radiation L is then applied to the liquid crystal coating film 4 through the halftone mask 10 (FIG. 1B). ). At this time, the polymerizable functional groups of the polymerizable liquid crystal compound undergo a polymerization reaction, and the liquid crystal coating film 4 is cured by this polymerization reaction. In addition, in the polymerizable liquid crystal compound having two or more polymerizable functional groups, a cross-linking polymerization reaction between the polymerizable liquid crystal compounds occurs depending on the conditions of the polymerization reaction.

The actinic radiation L is a concept including both electromagnetic waves including ultraviolet rays and particle beams having energy quanta that can polymerize molecules including electron beams. As the active radiation L, ultraviolet rays are preferably used. As the ultraviolet light, light having a wavelength of about 250 to 400 nm is used, and as its light source, an ultrahigh pressure mercury lamp, a high pressure mercury lamp, a xenon lamp, a metal halide lamp, or the like is used. Moreover, although the irradiation light quantity of an ultraviolet-ray changes with kinds and composition of a polymeric liquid crystal compound, the kind and quantity of a photoinitiator, it is the range of about 10-3000 mJ / cm < ² > normally.

  The halftone mask 10 is a photomask in which openings that can transmit light are patterned in a “predetermined pattern”, and the amount of light transmitted by changing the amount of light transmitted through the openings for each predetermined region. This is a multi-tone photomask with various types.

  The pattern of the opening in the halftone mask 10 is “the position and shape of the phase difference layer 9 and the phase difference of the phase difference layer 9 divided on the basis of the phase difference given to the incident light flux and the phase difference between the portions. "The position and shape at which the opening is formed, the line width and the amount of transmitted light for a predetermined region in the opening".

  That is, in the halftone mask 10, the opening is linear (partially linear with a different width) at a position corresponding to the “region where the linear retardation layer 9 is to be formed on the substrate 2”. Is formed. Further, in the halftone mask 10, regions in the in-plane direction of the retardation layers 9 a, 9 b, and 9 c that are classified according to the difference in the retardation required for the retardation layer 9 (in the divided region (FIG. 1B)). Are the areas of the liquid crystal coating film 4, which are the areas U 1, U 2, and U 3)), and have different light transmittances and line widths. That is, the opening has different “transmitted light amount and line width” for each portion corresponding to the segmented region of the retardation layer 9.

  For example, as shown in FIG. 1B, in the halftone mask 10, a region determined corresponding to the region where the retardation layer 9 exists is a light transmissive portion, and that portion is an opening. In FIG. 1C, the phase difference required for the phase difference layer 9 is given to the light flux that has passed through any of the colored layers 5, 6, and 7 among the light flux incident on the color filter 1. It depends on whether the phase difference should be met. In that case, the opening of the halftone mask is opposed to “the liquid crystal coating film 4 formed facing the portions of the color filter layer 3 corresponding to the colored layers 5, 6, and 7 of the color filter layer 3”. The pattern is formed for each of the “parts to perform” with different light transmittance and line width. Specifically, “each part of the liquid crystal coating film 4 facing the colored layers 5, 6, 7” (each of the liquid crystal coating film 4 corresponding to each of the regions U 1, U 2, U 3 of the phase difference layers 9 a, 9 b, 9 c). The portion of the opening facing the region is regions R1, R2, and R3. For each of the regions R1, R2, and R3, the halftone mask 10 sets the light transmittance to the transmittance of the region R1> the transmittance of the region R2> the transmittance of the region R3, and the line width (light is transmitted). The opening is patterned so that the width in the short side direction of the opening, which is a transparent portion, satisfies the line width of the region R1 <the line width of the region R2 <the line width of the region R3.

  In the second stage, after the liquid crystal coating film 4 is cured, the liquid crystal coating film 4 forming the retardation layer 9 is preferably developed and further baked (post-baked) (baking treatment). In the firing treatment, the firing temperature and firing time vary depending on the type and composition of the polymerizable liquid crystal compound and the reaction initiation temperature of an additive such as a polymerization initiator, etc., but usually 150 ° C. to 260 ° C., The range is from about 10 minutes to 60 minutes.

  In this way, in the color filter manufacturing method, the linear phase difference layer 9 that gives a partially different phase difference to the light flux incident on the color filter 1 is formed. That is, by performing the second stage using the halftone mask 10 as described above, the linear phase difference layer 9 (9a, 9b, 9c) having a desired phase difference distribution pattern is formed. (FIGS. 1A and 1C).

  When manufacturing a color filter having a retardation layer, simply using a halftone mask as before will form a "linear retardation layer that gives a partially different phase difference to the incident light beam". When trying to do so, there is a concern that the line width of the retardation layer may change according to the difference in transmittance of the opening of the halftone mask. In this regard, according to the present invention, the retardation layer as described above can be formed so that the line width thereof is substantially constant. Therefore, in order to make the line width of the retardation layer uniform, There is no need to cover a relatively wide line with a black matrix, reducing the need to reduce the light transmitting area in the color filter, ensuring an aperture ratio in the color filter, and further improving the white balance of the color filter. Can keep.

  In the first embodiment of the present invention, the color filter layer forming step is performed before the retardation layer forming step. Therefore, when looking at all the steps for manufacturing the color filter, the color filter layer forming step can be reduced to the steps to be performed after the retardation layer is formed. As described above, when the number of steps to be performed after forming the retardation layer is reduced, it is easy to predict whether or not the phase difference is reduced due to the steps performed after forming the retardation layer.

[Second Embodiment]
In the first embodiment of the present invention described above, the color filter layer forming step is performed before the retardation layer forming step. However, the present invention is not limited to this, but before the color filter layer forming step. The retardation layer forming step may be performed (second embodiment) (FIG. 2).

  That is, the manufacturing method of the second embodiment includes a color filter layer forming step and a retardation layer forming step, and the retardation layer forming step is performed before the color filter layer forming step.

  First, in the manufacturing method of the second embodiment, the individual color filter layer forming step and the retardation layer forming step are the same as those in the first embodiment except that the execution order of the forming steps of the color filter layer and the retardation layer is changed. It is the same process as the form. However, in the retardation layer forming step, the surface serving as the base for forming the liquid crystal coating film 4 is not the surface of the color filter layer 3 but the surface of the substrate 2. Further, in the color filter layer forming step, at least a part of a surface serving as a base for forming the color filter layer 3 becomes the retardation layer 9.

  In the manufacturing method of the second embodiment, a retardation layer 9 (9a, 9b, 9c) is formed on a substrate, and a predetermined color / predetermined in a predetermined position on the retardation layer 9. The colored layers 5, 6, and 7 having a thickness of 5 are formed, and the color filter layer 3 is formed by the colored layers 5, 6, and 7 (FIG. 2).

  In addition, thicknesses such as the thickness of the colored layer and the thickness of the retardation layer are values indicated by a stylus step meter.

  In the second embodiment of the present invention, the retardation layer forming step is performed before the color filter layer forming step. Therefore, according to the second embodiment of the present invention, the color filter 1 having a configuration in which the retardation layer 9 is covered with the color filter layer 3 is obtained. At this time, the retardation layer 9 is formed on the base material 2 having a relatively smooth surface, and the possibility that the orientation of the retardation layer 9 is disturbed is suppressed. It becomes easy to achieve a highly reliable state. Therefore, according to the present invention, it is possible to obtain the color filter 1 that meets strict requirements for electrical reliability.

[Third Embodiment]
In the manufacturing method of the first or second embodiment, the black matrix 8 that blocks light is formed in a pattern that partitions a plurality of types of colored layers 5, 6, and 7 in plan view of the color filter 1. The black matrix formation process to provide may be provided (3rd Embodiment) (FIG. 3). FIG. 3 is a plan view (FIG. 3A) and a cross-sectional view (FIG. 3B) for explaining an example of the color filter 1 when the black matrix 8 is formed on the surface of the substrate 2. FIG.

(Black matrix formation process)
As shown in FIG. 3, a light-shielding black matrix 8 is formed in a predetermined region on the surface of the substrate 2. The black matrix 8 can be formed by a method similar to the method of forming the colored layer, such as a method of coating an organic material containing a black pigment or the like on the surface of the substrate 2. The black matrix 8 is appropriately formed in a predetermined pattern such as a lattice shape according to various conditions such as the formation pattern of the colored layers 5, 6, and 7.

  In the manufacturing method of the first embodiment or the manufacturing method of the third embodiment subordinate to the manufacturing method of the first embodiment, the retardation layer forming step is performed after the color filter layer forming step. Before, the intermediate | middle layer formation process which forms an intermediate | middle layer between a colored layer and a phase difference layer may be performed. This intermediate layer forms a planarized surface. Therefore, the intermediate layer is formed by performing the intermediate layer forming step, so that the retardation layer can be formed on a flat surface in the subsequent retardation layer forming step.

[Liquid crystal display device incorporating a color filter]
The color filter 1 can be obtained by the production method of the present invention. For example, the color filter 1 can be used by being incorporated in a transflective liquid crystal display device as described below.

  A liquid crystal display device (semi-transmissive / semi-reflective liquid crystal display device) using the color filter 1 manufactured by the manufacturing method of the present invention will be described by taking a liquid crystal display device having a driving method as a VA mode as an example (FIG. 4). . FIG. 4 is a perspective view schematically showing a configuration of a transflective liquid crystal display device.

  As shown in FIG. 4, the transflective liquid crystal display device 30 has a liquid crystal 44 light between a pair of substrates 25 (first substrate 22 and second substrate 23) facing each other according to an applied voltage. A liquid crystal cell 40 formed by forming a driving liquid crystal layer 28 in which a liquid crystal material 24 is sealed with a variable axis direction is provided, and two polarizing plates 19 and 20 are provided outside the liquid crystal cell 40 in the thickness direction. Further, a backlight (not shown) is provided on the outside thereof. The backlight is provided so that light is incident on the second substrate 23 at a position further outside the polarizing plate of the second substrate 23.

  The transflective liquid crystal display device 30 has a reflective display function and a transmissive display function. The liquid crystal cell 40 is formed with a reflective portion 60 that is defined as a portion that exhibits a reflective display function and a transmissive portion 61 that is defined as a portion that exhibits a transmissive display function.

  The first substrate 22 and the second substrate 23 respectively include a glass substrate 110 and a glass substrate 111 as the base material 2, and the first substrate 22 has a black matrix 8 and a colored layer on the glass substrate 110. A color filter layer 3 composed of 5, 6, and 7 is laminated, and an alignment film (not shown) is laminated on the color filter layer 3. Further, on the first substrate 22, the retardation layer 9 is patterned on a portion of the alignment film corresponding to the reflective portion 60. The phase difference layer 9 depends on “the color layer (colored layer 5, 6, 7) facing the portion disposed and formed through the alignment film”. The phase difference is different. That is, of the incident light beams incident on the phase difference layer 9, the phase differences given to the portions of the light beams that have passed through the colored layers 5, 6, and 7 are different from each other. The retardation layer 9 is formed in a linear shape, and a plurality of the retardation layers 9 are formed side by side in the lateral direction, and the longitudinal direction thereof is aligned, and the retardation distribution pattern corresponds to the distribution pattern of the colored layer. In this example, the retardation layer 9 is a layer that exhibits an optical function of causing a quarter-wave phase difference in light.

  Further, on the first substrate 22, the column bodies 50 are further distributed and arranged at predetermined positions (column body formation planned positions) using a known method such as a photolithography method. The column 50 is made of a photocurable resin material such as an acryl-based and amide-based or ester-based polymer containing a polyfunctional acrylate. The height of the column 50 is set according to the distance between the first substrate 22 and the second substrate 23.

  Further, in the first substrate 22, the polarizing plate 19 is disposed on the outer surface side of the glass substrate 1.

  The second substrate 23 includes a reflection film 34 that reflects light at a portion corresponding to the reflection portion 60, and a portion that can transmit light using a portion corresponding to the transmission portion 61 as a non-installation region of the reflection film 34. Further, a transparent conductive film 45 such as a TFT (not shown) or ITO which forms a driving circuit for switching driving whether or not voltage is applied to the liquid crystal 44 of the driving liquid crystal layer 28 is laminated, and these are laminated. An alignment film (not shown) is formed so as to cover it.

  The first substrate 22 and the second substrate 23 are kept at a predetermined interval (cell gap) by bringing the tip K of the column 50 into contact with the second substrate 23. At this time, the cell gap is determined so that the cell gap of the reflection part 60 is about ½ of the cell gap of the transmission part 61.

  The liquid crystal display device 30 may be configured such that a retardation film 31 is interposed between the polarizing plate 19 and the glass substrate 1 and the viewing angle compensation is performed by the retardation film 31 as necessary. Good.

  In this specification, the transflective liquid crystal display device 30 uses the VA mode as the driving method of the liquid crystal 44 of the driving liquid crystal layer 28, but the driving method is not limited to this.

[Method for producing color filter used in transflective liquid crystal display]
The manufacturing method according to any one of the first to third embodiments is configured to be able to manufacture a color filter used in the transflective liquid crystal display device 30 having the transmissive display function and the reflective display function as described above. It may be. Here, the color filter used in the transflective liquid crystal display device 30 corresponds to a transmissive portion determined corresponding to an area displayed by the transmissive display function and an area displayed by the reflective display function. And a reflection portion defined by

  This color filter can be manufactured by performing the retardation layer forming step in the following manner in the manufacturing method of any of the first to third embodiments, and forming the retardation layer 9 by patterning. . In the phase difference layer forming step, as shown in FIG. 5, as the halftone mask 10, a linear shape capable of transmitting light according to the formation pattern of the reflection portion 60 (the portion where the linear phase difference layer 9 is formed). The opening 11 as a region (a linear region having a partially different width) (region Q in FIG. 5) is patterned, and light is transmitted in a predetermined region corresponding to the divided region of the retardation layer 9 Those with different rates and line widths are prepared. For example, for the regions q1, q2, and q3 in the opening 11, the light transmittance of the region q1> the light transmittance of the region q2> the light transmittance of the region q3. Further, the relationship between the line widths in the opening 11 is such that the line width of the region q1 <the line width of the region q2 <the line width of the region q3, and the halftone mask 10 shown in FIG. The line widths S1, S2, and S3 of the regions q1, q2, and q3 in the region Q are S1 <S2 <S3. That is, the halftone mask 10 is prepared in which a predetermined pattern is formed so that the retardation layer 9 can be formed on the reflection portion 60 while avoiding the transmission portion 61. Then, with the halftone mask 10, a linear retardation layer 9 that imparts a partially different phase difference to the incident light beam incident on the color filter is formed by patterning.

  Thus, according to the present invention, a transflective liquid crystal display device using a color filter having a retardation layer can be obtained.

  Below, the Example of this invention and the comparative example with respect to this are shown.

(Preparation of base material)
A glass substrate (low expansion coefficient non-alkali glass plate (Corning, 1737 glass) (length 100 mm × width 100 mm, thickness 0.7 mm)) was prepared as a base material.

(Preparation of organic material for forming black matrix, coloring material dispersion for forming colored layer)
A pigment dispersion type photoresist (each of which is an organic material for forming a black matrix, and a coloring material dispersion for forming a colored layer corresponding to each color type of red (R), green (G), and blue (B). BM photoresist, red photoresist, green photoresist, blue photoresist).

  For the coloring material dispersion, the components constituting the transmission part and the reflection part (the colored layer for the transmission part and the coloring layer for the reflection part) are divided into the spectral components of the transmission part and the reflection part for each color of RGB. Prepared according to the concentration. Thereby, a total of six types of pigment-dispersed photoresists were prepared.

  A pigment dispersion type photoresist uses a pigment as a coloring material, adds beads to a dispersion composition (containing a pigment, a dispersant, and a solvent), disperses for 3 hours with a disperser, and then removes the beads. A clear resist composition (containing polymer, monomer, additive, initiator and solvent) is mixed. The composition components and blending amounts of various pigment-dispersed photoresists are shown below. A paint shaker (manufactured by Asada Tekko Co., Ltd.) was used as the disperser.

(1) Photoresist for BM, black pigment, 14.0 parts by weight (manufactured by Dainichi Seika Kogyo Co., Ltd.) TM Black # 95550)
・ Dispersant ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ 1.2 parts by weight (manufactured by Big Chemie, Disperbic 111)
・ Polymer ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ 2.8 parts by weight (made by Showa Polymer Co., Ltd., (meth) acrylic resin, product no. : VR60)
・ Monomer ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ 3.5 parts by weight (manufactured by Sartomer, polyfunctional acrylate, product number: SR399)
Additive (dispersibility improver) ... 0.7 part by weight (manufactured by Soken Chemical Co., Ltd., Chemtry L-20)
-Initiator ... 1.6 parts by weight (2-benzyl-2-dimethylamino-1- (4- Morpholinophenyl) -butanone-1)
・ Initiator (4,4'-diethylaminobenzophenone) ... 0.3 parts by weightInitiator (2,4-diethylthioxanthone) ... 0.1 parts by weight Solvent (ethylene glycol monobutyl ether) ... 75.8 parts by weight

(2) Red photoresist / red pigment (CIPR254) ... 1.75 parts by weight (Ciba Specialty Chemicals Co., Ltd., Chromoval DPP Red) BP)
・ Yellow pigment (CI PY139): 0.3 part by weight (manufactured by BASF, Paliotor Yellow D1819)
・ Dispersant ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ 1.5 parts by weight (Zeneca Co., Ltd., Solsperse 24000)
・ Polymer 1 (below) ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ 5.0 parts by weight ・ Monomer ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・... 4.0 parts by weight (manufactured by Sartomer Co., Ltd., polyfunctional acrylate, product number: SR399)
・ Initiator ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ 1.4 parts by weight (Ciba Specialty Chemicals Co., Ltd., Irgacure 907)
-Initiator ... 0.6 parts by weight (2,2'-bis (o-chlorophenyl) -4, 5,4 ′, 5′-tetraphenyl-1,2′-biimidazole)
・ Solvent ... 85.4 parts by weight (propylene glycol monomethyl ether acetate)

  However, polymer 1 is based on 100 mol% of copolymer of benzyl methacrylate: styrene: acrylic acid: 2-hydroxyethyl methacrylate = 15.6: 37.0: 30.5: 16.9 (molar ratio), 2-Methacryloyloxyethyl isocyanate is added with 16.9 mol%, and the weight average molecular weight is 42500.

  In addition, the said composition is a composition of the photoresist for red for reflection parts. As the red photoresist for the transmission portion, a red pigment, a yellow pigment, and a dispersant were prepared in amounts that were twice the above amounts, respectively.

(3) Green photoresist The same composition component as the red photoresist except that the following green pigment and yellow pigment were used in the following amounts instead of the red pigment and yellow pigment in the red photoresist. The same amount was used.
-Green pigment (CIPG7) ... 1.9 parts by weight (Daiichi Seika Seika Fast Green 5316P))
-Yellow pigment (CI PY139) ... 1.1 parts by weight (manufactured by BASF, Paliotor Yellow D1819)

  In addition, the said composition is a composition of the green photoresist for reflection parts. As the green photoresist for the transmissive portion, a green pigment, a yellow pigment, and a dispersant were each prepared in double amounts as described above.

(4) Blue pattern forming photoresist Instead of the red pigment, yellow pigment, and dispersion in the above-described red photoresist, the following blue pigment, purple pigment, and dispersion are used in the following amounts, and The same composition components as the red photoresist were used in the same amount except that the following pigment derivatives were used in the following amounts.
-Blue pigment (CI PB15: 6) ... 2.3 parts by weight (BASF Heliogen Blue L6700F))
・ Purple pigment (CI PV23) ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ 0.7 parts by weight (Clariant, Foster Palm RL-NF)
・ Pigment derivative ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ 0.3 parts by weight (Solsperse 12000 manufactured by Zeneca)
・ Dispersant ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ 1.2 parts by weight (Solsperse 24000 manufactured by Zeneca)

  The above composition is the composition of the blue photoresist for the reflective portion. A blue photoresist for the transmission part was prepared by adding the green pigment, the yellow pigment, the dispersant, and the pigment derivative in double amounts as described above.

(Preparation of liquid crystal composition liquid for forming retardation layer)
As the liquid crystal composition for forming the retardation layer, a liquid crystal composition liquid having the following composition was prepared. Composition components other than the solvent shown in each composition of the following liquid crystal composition liquids 1 and 2 are mixed in the following blending amounts (parts by weight) corresponding to the respective composition components and dissolved in the following solvents, respectively. A liquid crystal composition as a polymerizable liquid crystal composition for forming a retardation layer was prepared.

(Composition of liquid crystal composition liquid)
Polymerizable liquid crystal compound ... 28.75 parts by weight (compound in which a and b are both 6 in chemical formula 11)
Photopolymerization initiator ... 1.24 parts by weight (Irgacure 907 (Ciba Specialty Chemicals))
Polymerization inhibitor: 0.01 parts by weight (2,6-di-t-butyl-p-cresol)
Solvent ... 70.00 parts by weight (diethylene glycol dimethyl ether)

Example 1

(Formation of black matrix)
The BM photoresist is applied onto the cleaned glass substrate by spin coating, the solvent is reduced by drying under reduced pressure, and pre-baked (prebaked) at 80 ° C. for 3 minutes to provide a striped BM. After exposure (100 mJ / cm ² ) using a mask formed with such a pattern, followed by spray development using a 0.05% KOH aqueous solution for 60 seconds, firing was performed at 230 ° C. for 30 minutes ( Post-baking) was performed to form a BM having a thickness of 1.2 μm. In this way, what formed BM on the glass substrate surface (it is called BM board | substrate) was obtained.

(Formation of color filter layer)
Next, the blue photoresist for the reflective part is applied onto the BM substrate by spin coating, the solvent is removed by drying under reduced pressure, and prebaked at 80 ° C. for 3 minutes to form a blue colored layer pattern. Alignment exposure (100 mJ / cm ² ) was performed using a photomask on which a corresponding pattern was formed. Subsequently, spray development using a 0.1% KOH aqueous solution was performed for 60 seconds, followed by post-baking at 230 ° C. for 30 minutes to form a blue colored layer for the reflective portion so as to have a predetermined positional relationship with the BM pattern. Formed.

  Furthermore, in the same manner as the method for forming the blue colored layer for the reflective part on the BM substrate, the green colored layer for the reflective part, the red colored layer for the reflective part, the blue colored layer for the transmissive part, and the transmissive part By forming the green colored layer and the red colored layer for the transmission part, a “substrate on which the color filter layer was formed” was obtained. The film thickness (target film thickness) of each color layer for the reflective portion and the film thickness (target film thickness) of each color layer for the transmissive portion were both 1.3 μm. Here, the pattern of the colored layer for the reflective portion and the pattern of the colored layer for the transmissive portion are patterns in which red, green, and blue colored layers are arranged in the order of frames, respectively. The pixel pattern composed of the colored layer pattern of the reflective portion and the pixel pattern composed of the colored layer pattern of the transmissive portion are intermittently provided with a substantially rectangular light transmissive portion in a predetermined direction at a predetermined position in the in-plane direction of the glass substrate. It is a pattern formed by arranging in a lattice pattern, and is a pattern in which red, green, and blue colored layers are arranged in a surface order (FIG. 6). In FIG. 6, the BM substrate is indicated by the symbol U, the black matrix is indicated by the symbol M, and the red, green, and blue colored layers are the symbols C (R), C (G), and C (B). The red colored layer, the green colored layer, and the blue colored layer for the reflective portion are indicated by the symbols C (R1), C (G1), and C (B1), and the red colored layer for the transmissive portion is green. The colored layer and the blue colored layer are denoted by reference numerals C (R2), C (G2), and C (B2). A substrate in which a color filter layer composed of a colored layer is formed on a BM substrate is referred to as a CF substrate.

(Formation of retardation layer)
On the surface of the CF substrate (on the surface on which the color filter layer is formed on the two front and back surfaces of the CF substrate), an alignment film forming composition (manufactured by JSR Corporation, AL1254) is applied using a spin coater, The coating film was formed so that the film thickness of the coating film was 0.1 μm or less, and baked in an oven at 230 ° C. for 30 minutes. Next, using a rubbing apparatus, the coating film was subjected to an alignment treatment to form an alignment film.

  Thereafter, the liquid crystal composition liquid for forming the retardation layer prepared above was applied onto the alignment film surface by a spin coating method to obtain a liquid crystal coating film, and prebaked at 80 ° C. for 3 minutes. Next, a halftone mask was prepared in which a pattern was formed corresponding to the phase difference formation pattern of the reflecting portion (a linear pattern crossing the colored layer of the reflecting portion). That is, the pattern formed on the halftone mask is a pattern formed in a “line shape that crosses the colored layer forming portion of the reflective portion of the color filter layer in plan view of the CF substrate”. Further, the pattern formed on the halftone mask was formed so that the transmittance and the line width were different for each divided region of the retardation layer. The divided region of the retardation layer corresponds to a region that is divided for each region facing the formation portion of the red colored layer, the green colored layer, and the blue colored layer. Therefore, the openings of the halftone mask are formed to have different transmittances and line widths corresponding to the respective portions of the liquid crystal coating film facing the formation portions of the red colored layer, the green colored layer, and the blue colored layer. It was done. At this time, the transmittance of the opening was designed to be 100, 80, and 60%, respectively, according to the segmented regions corresponding to the red colored layer, the green colored layer, and the blue colored layer forming portion of the color filter layer. Furthermore, the line widths of the openings were designed to be 23, 24, and 25 μm, respectively, according to the divided areas corresponding to the formation portions of the red colored layer, the green colored layer, and the blue colored layer. Here, 100% indicates that the transmittance of the portion with the highest transmittance (the portion corresponding to the portion where the red colored layer is formed) is 100%. In that case, the transmittance of the portion corresponding to the formation portion of the green coloring layer and the blue coloring layer is relatively 80% and 60%.

Through this halftone mask, alignment exposure (200 mJ / cm ² ) was performed on the liquid crystal coating film, and then butt development was performed for 5 seconds using methyl ethyl ketone (MEK), and then post-baking was performed at 230 ° C. for 30 minutes. Thus, a color filter was obtained in which the retardation layer was formed in a linear shape that crossed the colored layer of the reflective portion on the CF substrate.

(Measurement of line width for each color filter retardation layer)
The line width of the retardation layer in the obtained color filter was measured with a dimension measuring machine (AMIC-1300, manufactured by Sokkia Co.). At this time, the line width of the retardation layer was measured for each divided region of the retardation layer of the color filter, that is, for each region corresponding to the colored layer. The results are shown in Table 1.

(Measurement of phase difference of colored layers of each color filter)
The retardation (nm) generated in the light passing through the retardation layer of the obtained color filter was measured as follows. For the measurement, a microspectrophotometer OSP-SP200 manufactured by Olympus and two polarizing plates were used. First, the two polarizing plates are arranged one above the other so that the optical axes of the two polarizing plates are parallel, and the optical axis of the retardation layer is at an angle of 45 ° with respect to the optical axis of the polarizing plate. The color filter was sandwiched between the two polarizing plates, and the spectral transmittance of light incident from the lower polarizing plate and transmitted through the upper polarizing plate was measured. Next, by rotating the upper polarizing plate by 90 ° with the rotation axis in the thickness direction of the color filter, the two polarizing plates are brought into a state in which their optical axes cross each other. Spectral transmittance was measured. Based on the measurement result of the spectral transmittance, the phase difference for the light passing through the colored layer of each color was calculated by the rotational analyzer method. Measurement and calculation were performed for each color pixel. When measuring the phase difference using a microspectrophotometer, a measurement spot (measurement spot diameter of 10 μm) is selected in the central part of the colored layer formation region of each color in plan view of the color filter, and the measurement spot is ranked. Phase difference was measured. Thereby, the phase difference for each segmented region of the phase difference layer of the color filter is measured. The results are shown in Table 1.

Comparative Example 1
Instead of the halftone mask used in Example 1, the transmittance is 100, 80, 60%, depending on the divided region corresponding to the red colored layer, the green colored layer, and the blue colored layer forming portion of the color filter layer. The same method as in Example 1 was performed, except that a halftone mask having openings designed to have line widths of 25, 25, and 25 μm was used. Using the color filter thus obtained, the same method as in Example 1 was used to measure the line width for each segmented region of the phase difference layer of the color filter and the phase difference of the colored layer of each color. The results are shown in Table 1.

Comparative Example 2
Instead of the halftone mask used in Example 1, the transmittance is 100, 100, 100%, depending on the divided region corresponding to the formation portion of the red colored layer, the green colored layer, and the blue colored layer of the color filter layer. The same method as in Example 1 was performed, except that a halftone mask having openings designed to have line widths of 25, 25, and 25 μm was used. Using the color filter thus obtained, the same method as in Example 1 was used to measure the line width for each segmented region of the phase difference layer of the color filter and the phase difference of the colored layer of each color. The results are shown in Table 1.

Example 2
(Formation of black matrix)
The step of forming the black matrix was performed by the same method as in Example 1.

(Formation of retardation layer)
A retardation layer was formed on the surface of the BM substrate (on the BM formation surface of the two surfaces of the BM substrate) in the same manner as in Example 1. However, the opening of the halftone mask has a transmittance and a line width corresponding to each part of the liquid crystal coating film that is expected to face the formation part of the red colored layer, the green colored layer, and the blue colored layer later. It is formed to be different. At this time, the transmittance was designed to be 100%, 80%, and 60%, respectively, depending on the divided areas that will correspond to the red color layer, the green color layer, and the blue color layer formation portion of the color filter layer. Furthermore, the line width was designed to be 23, 24, and 25 μm, respectively, according to the divided areas corresponding to the formation portions of the red colored layer, the green colored layer, and the blue colored layer later.

(Formation of color filter layer)
Next, the six kinds of photoresists for each color adjusted as described above are applied by spin coating on the substrate on which the retardation layer is formed (on the surface on which the retardation layer is formed), and the reflecting portion is colored red. A color filter layer was formed in the same manner as in Example 1 except that the layer, the green color layer, the blue color layer, and the red color layer, green color layer, and blue color layer of the transmission part were formed.

  In this way, a color filter was obtained in which the retardation layer was formed in a linear shape across the colored layer of the reflective portion on the BM substrate, and the color filter layer was formed on the retardation layer. Using the obtained color filter, the line width measurement for each divided region of the retardation layer of the color filter and the retardation measurement of the colored layer of each color were performed in the same manner as in Example 1. The results are shown in Table 1.

Comparative Example 3
Instead of the halftone mask used in Example 2, the transmittance is 100, 100, 100%, depending on the divided region corresponding to the red colored layer, the green colored layer, and the blue colored layer forming portion of the color filter layer. The same method as in Example 2 was performed except that a halftone mask having openings designed to have line widths of 25, 25, and 25 μm was used. Using the color filter obtained in this manner, the line width measurement for each divided region of the phase difference layer of the color filter and the phase difference measurement of the colored layer of each color were performed in the same manner as in Example 2. The results are shown in Table 1.

DESCRIPTION OF SYMBOLS 1 Color filter 2 Base material 3 Color filter layer 4 Liquid crystal coating film 5, 6, 7 Colored layer 8 Black matrix 9 Phase difference layer 10 Halftone mask 11 Opening part 19, 20 Polarizing plate 22 1st board | substrate 23 2nd board | substrate 24 Liquid crystal material 25 A pair of substrates 28 A liquid crystal layer for driving 30 A liquid crystal display device 31 A retardation film 34 A reflective film 40 A liquid crystal cell 44 A liquid crystal 50 A column 60 A reflective portion 61 A transparent portion 110,111 A glass substrate R1, R2, R3, q1, q2, q3 Predetermined area in halftone mask Q Area of light transmitting part in halftone mask L Traveling direction of irradiated light

Claims (5)

A base material having optical transparency, a color filter layer having a plurality of colored layers and provided directly or indirectly to the base material, and a partially different phase difference with respect to the incident light flux A method for producing a color filter comprising a retardation layer provided in a linear pattern at a predetermined position directly or indirectly,
A color filter layer forming step of providing a plurality of colored layers directly or indirectly on the substrate;
A retardation layer forming step of forming a retardation layer in a linear pattern at a predetermined position directly or indirectly with respect to the substrate, and
In the retardation layer forming step, a liquid crystal composition containing a liquid crystal compound having a polymerizable functional group is applied directly or indirectly to a substrate to form a liquid crystal coating film, and the liquid crystal contained in the liquid crystal coating film A liquid crystal compound contained in the liquid crystal coating film is polymerized by irradiating the liquid crystal coating film with actinic radiation through a first step of aligning the compound in a predetermined direction and a halftone mask having openings of a predetermined pattern. A second stage,
In the halftone mask used in the second stage, an opening is formed at a position determined according to the formation position of the linear retardation layer, and the opening has a difference in phase difference given to the incident light beam. Each of the predetermined portions corresponding to the portion of the retardation layer divided based on the light transmittance, and the opening portion is larger than the line width of the portion where the light transmittance is high in the opening portion. A method for producing a color filter, characterized in that the line width of a portion having a low light transmittance is increased.   The method for producing a color filter according to claim 1, wherein a retardation layer forming step is performed after the color filter layer forming step.   The method for producing a color filter according to claim 1, wherein a color filter layer forming step is performed after the retardation layer forming step. Used in a transflective display device having both transmissive and reflective liquid crystal display functions, and a transmissive portion defined corresponding to a portion that exhibits the transmissive liquid crystal display function, and a reflective liquid crystal display A method of manufacturing a color filter comprising a reflective portion determined corresponding to a portion that exhibits a function,
The method for producing a color filter according to any one of claims 1 to 3, wherein in the retardation layer forming step, the retardation layer is patterned so as to avoid the transmission portion and cover the reflection portion. A liquid crystal display device comprising a liquid crystal cell in which liquid crystal is sealed between a pair of facing substrates,
5. A liquid crystal display device, wherein a color filter obtained by the manufacturing method according to claim 1 is incorporated as one of substrates constituting a liquid crystal cell.

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