JP2691955C - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION       [0001]     [Industrial applications]   The present invention relates to a color filter used for a liquid crystal display element or a liquid crystal-optical shutter array.
More specifically, the initial alignment state of liquid crystal molecules is improved To obtain a uniform monodomain liquid crystal phase without alignment defects,
Color filter substrate having color filter with improved driving characteristics and the same
And a liquid crystal element using the same.       [0002]     [Prior art]   Conventional liquid crystal elements include, for example, M. Schadt and Dub.
"Applied Physics" by W. Helfrich
・ Letters ”(“ Applied Physics Letters ”) No. 18
Vol. 4, No. 4 (published February 15, 1971), pp. 127-128, “Volte
The Dependent Optical Activity of a Twist
De Nematic Liquid Crystal (“Voltage Dependen
t Optical Activity of a Twisted Nema
tic Liquid Crystal ”)
A liquid crystal using a twisted nematic liquid crystal is known. this
The TN liquid crystal is used for time-division driving using a matrix electrode structure with a high pixel density.
Since there is a problem that crosstalk occurs, the number of pixels is limited.       [0003]   In addition, a switching element composed of a thin film transistor is connected to each pixel, and each pixel is
A display element that switches the current is known, but a thin film transistor is provided on the substrate.
Is very complicated, and it is difficult to produce a large-area display element.
There is a problem.       [0004]   To solve these problems, Clark et al.
Japanese Patent No. 4,367,924 proposes a ferroelectric liquid crystal device.       [0005]   FIG. 2 schematically illustrates a cell example for explaining the operation of the ferroelectric liquid crystal.
You. 21a and 21b are In_Two  O_Three  , SnO_Two  And ITO (Indium T
In a substrate (glass plate) covered with a transparent electrode composed of a thin film such as in oxide
In which a plurality of liquid crystal molecular layers 22 are oriented so as to be perpendicular to the glass surface. mC^*  Phase or SmH^*  Phase liquid crystals are enclosed. The line 23 indicated by the bold line is the liquid
The liquid crystal molecule 23 has a dipole in a direction perpendicular to the molecule.
It has a moment (P⊥) 24. Constant between the electrodes on the substrates 21a and 21b
When a voltage higher than the threshold is applied, the helical structure of the liquid crystal molecules 23 is unwound, and the dipole mode is applied.
The orientation of the liquid crystal molecules 23 is changed so that the
Can be obtained. The liquid crystal molecule 23 has an elongated shape, and its long axis direction is short.
It exhibits refractive index anisotropy in the axial direction, so that, for example,
If polarizers are placed in a positional relationship, the optical characteristics will change depending on the polarity of the applied voltage.
It can be easily understood that the liquid crystal optical modulation element becomes a liquid crystal optical modulation element.       [0006]   The liquid crystal cell preferably used in the ferroelectric liquid crystal element of the present invention has a sufficient thickness.
(For example, 10 μm or less). As the liquid crystal phase becomes thinner
Therefore, even when no electric field is applied as shown in FIG.
The structure is unwound and becomes a non-helical structure, and its dipole moment Pa or Pb is upward
(34a) or downward (34b). In such a cell,
As shown in FIG. 3, when an electric field Ea or Eb having a different polarity or more than a certain threshold is applied.
, The dipole moment is upwards corresponding to the electric field vector of the electric field Ea or Eb.
a or the downward direction 34b, and accordingly, the liquid crystal molecules are in the first stable state 3
It is oriented in either 3a or the second stable state 33b.       [0007]   The advantages of using such a ferroelectric liquid crystal as an optical modulation element are described above.
There are two. The first is that the response speed is extremely fast, and the second is that the liquid crystal molecules
Has bistability. The second point is further explained by, for example, FIG.
Specifically, when the electric field Ea is applied, the liquid crystal molecules are oriented to the first stable state 33a.
This state is stable even when the electric field is turned off. When an electric field Eb in the opposite direction is applied,
The liquid crystal molecules are oriented to the second stable state 33b and change the direction of the molecules.
This state remains even when the electric field is turned off. Also, the applied electric field Ea has a fixed threshold value.
As long as they do not exceed, each alignment state is also maintained. Such response speed
In order to achieve the speed and bistability effectively, the thinner the cell, the better Is preferred.       [0008]   In order for this ferroelectric liquid crystal element to exhibit predetermined driving characteristics, a pair of parallel substrates
The ferroelectric liquid crystal interposed between the two stable liquid crystals is independent of the applied electric field.
Must be in molecular alignment so that conversion between states can occur effectively
. For example, for a ferroelectric liquid crystal having a chiral smectic phase,
The liquid crystal molecular layer of the smectic phase is perpendicular to the substrate surface, and therefore the liquid crystal molecular axis
It is necessary to form a region (mono domain) arranged substantially parallel to the substrate surface.
However, in conventional ferroelectric liquid crystal devices, such a monodomain
The alignment state of the liquid crystal having the liquid crystal structure was not always satisfactorily formed.
It is a fact that no proper characteristics were obtained.       [0009]   FIG. 4 is a sectional view of a conventional ferroelectric liquid crystal device, and FIG. 5 is a conventional ferroelectric liquid crystal device.
FIG. 4 is a schematic explanatory view showing a state of an alignment defect appearing in an element.       [0010]   That is, the conventional ferroelectric liquid crystal element 40 shown in FIG.
42, and substrates 41 and 42 each have a matrix electrode structure.
Wipe-shaped transparent electrodes 43 and 44 are provided.       [0011]   Generally, color filters are red (R), green (G), blue (B) dyes or
Each dye layer has a thickness regardless of its formation method.
Since they are different, a step A of about 2000 ° to 1 μm is formed. As a result,
When the alignment is controlled using the process, the above-described step A causes the step A to be a boundary.
As a result, an alignment defect occurs in the ferroelectric liquid crystal 47. Also, this step A exists.
When alignment control films 45 and 46 are provided on existing substrates 41 and 42, respectively,
In the direction control film, a step C formed in accordance with the step A is generated by the film thickness of the pixel.
In the same manner as above, an alignment defect occurs in the ferroelectric liquid crystal 47.       [0012]   FIG. 5 shows a scan when the ferroelectric liquid crystal element was observed with a crossed Nicol polarizing microscope. The white line 51 in the figure is the line of the spacer (not shown) used for the liquid crystal element.
4 and lines 52 and 53 are observed corresponding to steps C on the substrate 41 of FIG.
I have. The portion 54 in the figure is a ferroelectric liquid crystal sandwiched between the opposing electrodes. side
A large number of edge lines 55 appearing in the light microscope represent alignment defects of the ferroelectric liquid crystal.
.       [0013]   If there is a certain level of step on the surface in contact with the ferroelectric liquid crystal,
Then, an alignment defect is generated, and the monodomain formation of the ferroelectric liquid crystal is inhibited.       [0014]     [Problems to be solved by the invention]   The present inventors have proposed such a step on a substrate, particularly a color filter as a ferroelectric liquid crystal.
In the case where the pixel is internally provided, a step generated when the distance between pixels exceeds 5 μm is strongly induced.
It has been experimentally confirmed that it is a cause of significant alignment defects for the conductive liquid crystal.
Clarified.       [0015]   An object of the present invention is to prevent the occurrence of the above-described alignment defects and to provide a ferroelectric liquid crystal element.
Color filter that can fully demonstrate the high-speed response and memory effect characteristics
Filter board andLiquid crystal elementIs to provide.       [0016]     [Means for Solving the Problems]   The present inventors have found that ferroelectric liquid crystals in particular have a liquid crystal phase (low temperature state) rather than an isotropic phase (high temperature state).
Focusing on the initial orientation during the cooling process, the ferroelectric liquid crystal moves to
With a structure that can achieve both the operating characteristics of the device based on GaN and the monodomain properties of the liquid crystal layer
They have found a dielectric liquid crystal element.       [0017]   The liquid crystal element of the present invention is based on such knowledge, and more specifically,
There is no step that induces alignment defects on the surface in contact with the crystal layer.
Good initial orientation during cooling process by avoiding drastic change
It is characterized in that a monodomain having no alignment defect is formed.       [0018]   That is, the present invention has a photosensitive group in a molecule, and has a wavelength of 400 nm to 700 nm.
Polyimide that has a light transmittance of 90% or more in the long range and cures at a temperature of 200 ° C or less
Having a colored resin comprising a resin and a colored material dispersed in the polyimide resin
A color filter substrate having a color filter with a substantially uniform thickness on the substrate.
Of the color filter of each adjacent pixelThe interval has an interval α, and the interval α is 0
μm <α ≦ 5 μm, the color filter and the space α
On the top, a protective layer is formed uniformly, and the surface of the protective layer on the color filter is
The step formed between the surface of the protective layer on α and the surface of the protective layer is set at 1000 ° or less.
aboveA color filter comprising a pattern-shaped transparent electrode.
-Substrate.       [0019]   In addition, the present invention sandwiches a chiral smectic liquid crystal between a pair of substrates to reduce
And a liquid crystal element having a color filter on one of the substrates.
Has a photosensitive group in the molecule, and has a sensitivity of 90% or less in a wavelength region of 400 nm to 700 nm.
A polyimide resin having the above light transmittance and curing at a temperature of 200 ° C. or less;
Red resin, blue resin and green resin consisting of a coloring material dispersed in an imide resin
The color filter has a substantially uniform thickness, and the color of each adjacent pixel is
Of the filterThe interval has an interval α, and the interval α is set to 0 μm <α ≦ 5 μm.
And a protective layer is uniformly formed on the color filter and the space α.
Between the surface of the protective layer on the color filter and the surface of the protective layer on the space α.
The step formed is set at 1000 ° or less, andPatterned transparent electrode
Is provided.       [0020]   Hereinafter, the present invention will be described with reference to the drawings.   FIG. 1 is a sectional view showing a basic configuration of a ferroelectric liquid crystal device according to the present invention. FIG.
In the above, the ferroelectric liquid crystal element 1 comprises a transparent plate such as a glass plate or a plastic plate.
Substrates 2 and 3 are used, and a ferroelectric liquid crystal 4 is interposed between them. Each board
The transparent electrodes 2 and 3 have a striped pattern forming a matrix electrode structure. The poles 5 and 6 are provided, and the orientation control films 7 and 8 are formed on the transparent electrodes.
You. Each of the R (red), G (green), and B (blue) color filters has the same thickness.
It is formed by setting the coloring material concentration in advance so as to obtain the desired spectral characteristics.
ing. On the other hand, in order to further planarize, if necessary,
A light-shielding layer 10 is formed in the recess between the layers, and a protective film or planarizing film 9 is further formed thereon.
Is formed.       [0021]   In the substrate having the above configuration, the thickness of the color filter is set to be substantially the same.
And the gap between pixels is kept to 5μm or less,
Since the steps are corrected, even if a transparent electrode and an alignment control film are formed in order on the pixel,
The substrate surface can be kept almost flat.       [0022]   According to the present invention, the level difference of the color filter substrate is reduced by 1000 °
Although it can be set as follows, it is desirable that it is preferably set to 500 ° or less. this
When the step exceeds 1000 °, in other words, the interval between each pixel exceeds 5 μm.
The liquid crystal element using the non-planarizing layer set in the above step has the alignment defect of the edge line shown in FIG.
It will cause a fall.       [0023]   As a color filter suitable for the present invention, the film thickness of each pixel is set to be substantially the same.
Any method can be used as long as it is possible, but the effect of the present invention is particularly large, and
Fine patterns can be formed by a simple manufacturing process.
Color filters with excellent properties such as heat resistance, light resistance, solvent resistance, etc.
Certain of the following schemes are preferred.       [0024]   That is, the optimal color filter for the present invention has a photosensitive group in the molecule.
Of a colored resin made by dispersing a coloring material in a low-temperature curing type polyimide resin
This is a method of forming by repeating a so-called process.       [0025]   More specifically, it has photosensitivity to form the colored resin layer of the color filter. Temperature-curable polyimide resin (hereinafter referred to as photosensitive polyimide resin)
(Hereinafter referred to as fat), a cured film can be obtained at 200 ° C. or lower, for example, 150 ° C.
A cured film can be formed by heat of about 30 minutes, for example, a polymer having a photosensitive group in its molecule.
Aromatic polyimide resin, especially specified in the visible light wavelength range (400 to 700 nm)
(A light transmittance of about 90% or more) is preferred.
In this respect, an aromatic polyimide resin is particularly preferable.       [0026]   Further, the photosensitive group in the present invention includes a photosensitive carbon group as shown below.
Any aromatic chain having a hydride unsaturated group may be used. (1) Benzoic acid esters       [0027] Embedded image       [0028] (Where R₁  Is CHX = CY-COO-Z-, X is -H or -C₆  H_Five  , Y is
-H or -CH_Three  , Z represents-or an ethyl group or a glycidyl group) (2) Benzyl acrylates       [0029] Embedded image       [0030] (Where Y is -H or CH_Three  Indicates) (3) diphenyl ethers       [0031] Embedded image       [0032] (Where R_TwoIs CHX = CY-CONH-, CH_Two= CY-COO- (CH_Two  )
_Two  -OCO- or CH_Two  = CY-COO-CH_Two  -Containing one or more, X
, Y indicate the above significance) (4) Chalcone and other compound chains       [0033] Embedded image       [0034] (Where R_Three  Represents H-, an alkyl group or an alkoxy group)       [0035] Embedded image       [0036] And the like.       [0037]   Specific examples of aromatic polyimide resins having these groups in the molecule are described as follows.
Socoat PI-400 "(trade name, manufactured by Ube Industries, Ltd.) and the like.       [0038]   Generally, the difference in the photosensitive resin used in the photolithography process depends on its chemical structure.
Despite its excellent mechanical properties, heat resistance, light resistance, and solvent resistance
There are few things. In contrast, the photosensitive polyimide resin of the present invention has a chemical structural
Also, these are resin systems with excellent durability, and color filters formed using them are
The durability of the filter is also very good. In particular, the color of ferroelectric liquid crystal devices
Heat resistance and liquid during sputter formation of transparent conductive film, which can be a problem as a filter
Damage to color filters due to inner spacers when assembling crystal elements
It demonstrates excellent performance.       [0039]   As a coloring material for forming a colored resin layer of the color filter in the present invention
Of organic pigments, inorganic pigments, dyes, etc.
However, there is no particular limitation. In this case, each material may be used alone.
It can also be used as a mixture of some of them. However, using a dye
In this case, the performance of the color filter is dominated by the durability of the dye itself.
However, when the resin system of the present invention is used, the performance is higher than that of a normal dyed color filter.
Excellent performance can be formed. Therefore, the color characteristics and various characteristics of the color filter
Considering performance, organic pigments are most preferable as the coloring material.       [0040]   As organic pigments, azo pigments such as soluble azo, insoluble azo, and condensed azo pigments can be used.
First, phthalocyanine pigments, and indigo, anthraquinone, peryl
Based, perinone based, dioxazine based, quinacridone based, isoindolinone based,
Condensed polycyclic pigments including taron, methine / azomethine, and other metal complex
Alternatively, mixtures of some of these are used.       [0041]   In the present invention, the colored resin used to form the colored resin layer is the photosensitive resin described above.
Colorant having desired spectral characteristics at the same film thickness for each color in a conductive polyimide resin solution Ingredients are mixed at an arbitrary ratio of about 10 to 50%, respectively, and
After sufficiently dispersing with a filter or the like, the particle size is preferably reduced with a filter of 1 μm or less.
Prepare by removing large ones.       [0042]   The colored resin layer of the color filter according to the present invention spins the colored resin.
Coating on the substrate with a coating device such as an inner coater or a roll coater.
It is formed in a more pattern shape, and its layer thickness is determined according to a desired spectral characteristic.
However, usually, the same film thickness of each color, about 0.5 to 5 μm, preferably 0.5 to 1.5 μm
m is desirable.       [0043]   If it is necessary to further increase the adhesion between the colored resin layer and the underlying substrate,
After thin coating with silane coupling agent etc. in advance,
Or add a small amount of a silane coupling agent, etc.
It is more effective to form a color filter using the additive.
.       [0044]   Note that the colored resin layer of the color filter in the present invention is itself sufficient.
Although it is composed of a good material with excellent durability,
To protect the colored resin layer or to flatten the color filter surface
In addition, polyamide, polyimide, polyurethane, polycarbonate
Organic resins such as silicates and silicon_Three  N_Four  , SiO_Two, SiO, Al_Two
O_Three  , Ta_Two  O_Three  Inorganic films such as spin coating and roll coating
Alternatively, the protective film or the planarizing film can be provided by an evaporation method.       [0045]   In this case, the surface of the color filter has a shape with less steps.
The present invention is more suitable for eliminating the alignment defect of the ferroelectric liquid crystal. Also
Since the thickness of the protective film 9 can determine the thickness of the ferroelectric liquid crystal 4,
It depends on the type of liquid crystal material, required response speed, etc. It is set in the range of 2 μm to 20 μm, preferably 0.5 μm to 10 μm.       [0046]   Further, in some cases, in order to improve display characteristics and to increase the gap between each pixel.
In order to reduce the level difference between pixels, light is shielded between pixels.
The layer is made of a metal thin film such as chrome
Light-shielding of carbon black, composite oxide black pigment, metal powder, etc. in optical polyimide resin
A light-shielding resin layer in which a material having a capability is dispersed can be formed by a coating method.       [0047]   Examples of the material for the alignment control film used in the present invention include polyvinyl alcohol.
, Polyimide, polyamide imide, polyester, polycarbonate, pyribi
Nyl acetal, polyvinyl chloride, polyvinyl acetate, polyamide, polystyrene
, Cellulose resin, melamine resin, urea resin, acrylic resin, etc.
Or photosensitive polyimide, photosensitive polyamide, cyclic rubber-based photoresist,
Nord novolak photoresist or electron beam photoresist (polymethyl
Methacrylate, epoxidized-1,4-polybutadiene, etc.)
Can be formed. Although the orientation control film 7 depends on the thickness of the ferroelectric liquid crystal,
Generally, it is set in the range of 10 to 1 μm, preferably 100 to 3000 °.       [0048]   A particularly suitable liquid crystal material used in the present invention is a liquid crystal having bistability.
It has ferroelectricity. Specifically, chiral smectic C phase
(SmC^*), H phase (SmH^*), Phase I (Sml^*), J phase (SmJ^*), K phase
(SmK^*), G phase (SmG^*) Or F phase (SmF^*) Can use liquid crystal
Wear.       [0049]   This ferroelectric liquid crystal is described in "Le Journal de Physique
("LE JOURNAL DE PHYSIQUE LETTRES")
1975,36(L-69), "Ferroelectric Liquid Chris
Tarus "(" Ferroelectric Liquid Crystals "
); "Applied Physics Letters" ("Applied Physi cs Letters ") 1980,36(11), “Submicro Seca
By bistable electro-optic switching in liquid
・ Crystals ”(“ Submicro Second Bistble El ”
electrooptic Switching in Liquid Cryst
als ");" Solid State Physics "1981,16(141), “Liquid crystal” etc.
In the present invention, the ferroelectric liquid crystal disclosed therein is used.
Can be.       [0050]   Specific examples of the ferroelectric liquid crystal include, for example, desyloxybenzylidene-p'-amido.
No-2-methylbutylcinnamate (DOBAMBC), hexyloxybenzide
Riden-p'-amino-2-chloropropylcinnamate (HOBACPC),
4-o- (2-methyl) -butylresorcylidene-4'-octylaniline (M
BRAS).       [0051]   When an element is formed using these materials, the liquid crystal compound is used as a chiral smectic.
In order to maintain the temperature in such a state that the phase becomes
It can be supported by an embedded block or the like.       [0052]     [Action]   The color filter substrate of the present invention and the liquid crystal element using the same are provided with a color filter for each pixel.
Filters are formed with almost the same thickness, and color filters of each adjacent pixel
Since the interval α (μm) is 0 ≦ α ≦ 5 μm, the flatness of the substrate is improved.
There is no step on the surface in contact with the liquid crystal phase, and the liquid crystal phase sandwiched between the substrates having good flatness is
The liquid crystal phase is cooled by slow cooling in the process of temperature transition from the isotropic phase to the liquid crystal phase.
The region gradually expands to form a uniform monodomain liquid crystal phase.       [0053]   For example, the above-mentioned DOBAMBC showing a ferroelectric liquid crystal phase as a liquid crystal is taken as an example.
To explain, when slowly cooling from the isotropic phase of DOBAMBC,
The phase changes to the tactic A phase (SmA phase). At this time, rubbing or Is SiO_Two  If an alignment process such as oblique deposition is performed, the molecular axis of the liquid crystal molecules
Mono-domains are formed in the plate that are parallel and oriented in one direction. Further cooling
At a specific temperature between about 90-75 ° C, which depends on the thickness of the liquid crystal layer.
Larsmectic C phase (SmC^*  Phase). Also, the thickness of the liquid crystal layer
When the thickness is about 2 μm or less, SmC^*  The helix of the phase unravels and shows bistability.       [0054]     【Example】   Hereinafter, the present invention will be described more specifically with reference to examples.   Example 1   FIGS. 6A to 6F are process diagrams showing a process of forming R, G, and B color pixels.
You.       [0055]   First, desired spectral characteristics are obtained on a Corning # 7059 glass substrate 61.
Blue colored resin material [Heliogen Bl
ue) L7080 (trade name, manufactured by BASF, CI No. 74160) as PI
-400C (trade name, manufactured by Ube Industries, polymer content = 10%, solvent: N-methyl
-2-pyrrolidone, pigment: polymer = 1: 2 blend)
Colored resin material] to a thickness of 1.5 μm by a spinner coating method.
Layer 62 was formed. (See FIG. 6 (a))       [0056]   Next, the colored resin layer 62 is pre-baked at 80 ° C. for 30 minutes and then formed.
Exposure with a high-pressure mercury lamp through a photomask 63 corresponding to the pattern shape
Glowed. (See FIG. 6B)       [0057]   After the completion of the exposure, as shown in FIG. 6C, the colored resin layer 62 having the photocured portion 62a
(N-methyl-2-pyrrolidone as a main component)
Develop with an ultrasonic wave and use a special rinse solution (for example, isopropyl
(Rinse solution mainly containing alcohol) at 200 ° C for 30 minutes.
Post-baking is performed, and a blue patterned colored resin layer 64 having a patterned shape is formed. Was formed. (See Fig. 6 (d))       [0058]   Subsequently, a green color is formed on the glass substrate on which the blue coloring pattern is formed as a second color.
Colored resin material [Lionol Green 6YK (product
Name, manufactured by Toyo Ink Co., Ltd., C.I. I. No. 74265) to PI-400C (trade name,
Ube Industries, polymer content = 10%, solvent: N-methyl-2-pyrrolidone, pigment
: Polymer = 1: 2)) and a photosensitive colored resin material prepared by dispersing
Outside, in the same manner as described above, the green patterned colored resin layer 65 is placed at a predetermined position on the substrate.
The gap was formed at a distance of 5 μm or less from the blue colored resin layer.       [0059]   Further, on the substrate on which the blue and green patterns are formed, a third
As the color, a red colored resin material [Irgazin Red]
BPT (trade name, manufactured by Ciba-Geigy), C.I.
71127) was replaced with PI-400C (trade name, manufactured by Ube Industries, polymer content = 10%,
(Solvent: N-methyl-2-pyrrolidone, pigment: polymer = 1: 2)
Red colored resin material] except that the prepared photosensitive colored resin material is used.
A green colored resin layer and a green colored resin layer are placed at predetermined positions on the substrate.
R (red), G (green), B
A colored pattern of a three-color stripe (blue) was obtained. (See FIG. 6 (e))       [0060]   Next, on a glass substrate on which a three-color coloring pattern is formed, a black
Color resin material [Carbon black (CI No. 77266) was replaced with PI-400C (
(Photopolymer prepared by dispersing polymer content = 10%, pigment: polymer = 1: 4)
Colored resin material] to match the gap between each pixel in the same manner as described above.
A light-shielding layer 67 having an optical pattern was formed. Thus, the interval α (μm) between the pixels is
, 0 ≦ α ≦ 5 μm.       [0061]   On the color filter pattern thus obtained, a protective film or a flattening film
The same transparent resin material [PI-400C (product Name, manufactured by Ube Industries, polymer content = 10%, solvent: N-methyl-2-pyrrolidone)
Was formed to a thickness of about 0.5 μm by a spinner coating method. (FIG. 6 (f
)reference)   As described above, it was possible to form a color filter substrate having the same plane.
.       [0062]   Next, as shown in FIG. 1, ITO is formed to a thickness of 500 ° by a sputtering method.
Thus, a transparent electrode 5 was obtained. On top of this, a polyimide forming solution (Japanese
Rikkasei Industries "PIQ") is applied by a spinner rotating at 3000 rpm, and 15
Heating was performed at 0 ° C. for 30 minutes to form a 2000 ° polyimide coating. After a while
The surface of this polyimide film was rubbed.       [0063]   The color filter substrate thus formed and the opposing substrate 3 are bonded together.
A cell was assembled, and a ferroelectric liquid crystal was injected and sealed to obtain a liquid crystal element. This liquid crystal element is
When observed with a Ross Nicol polarizing microscope, the liquid crystal molecules inside
Not confirmed.       [0064]   Comparative Example 1   The photosensitive polyimide resin used for the colored resin material of Example 1 was replaced with a photosensitive resin other than the present invention.
"Photo Nice" UR-3100 which is a functional polyimide resin (trade name, Toray Industries, Inc.)
Manufacture, solid content = 17%, solvent: N-methyl-2-pyrrolidone / methyl cellosolve mixture
Dedicated developer ("DV-140"), dedicated rinse (isopropyl
Alcohol) and post bake at 250 ° C for 30 minutes
R (red), G (green), and B (blue) in the same manner as in Example 1 except that
A stripe color filter was obtained.       [0065]   The color filter thus obtained was compared with the case of Example 1 with resin and face.
Because it is formed using a colored resin material that has a low affinity for
The surface flatness was poor.   Further, the color filter was inferior in transparency due to the characteristics of the resin.       [0066]   Further, using the obtained color filter substrate, the same method as in Example 1 was used.
When a dielectric liquid crystal element was formed and observed with a crossed Nicols polarizing microscope,
Poorly-aligned portions arising from portions with poor surface flatness were observed, affecting display characteristics.
The display contrast at this time is different from the display contrast obtained in the first embodiment.
Was reduced by a factor of 0.5.       [0067]   Comparative Example 2   The photosensitive polyimide resin used for the colored resin material of the first embodiment was replaced with a photosensitive acrylic resin.
"PHOTOREC" RFG-10 (trade name, Sekisui Fine Chemical Co., Ltd.)
), Solid content = 10%, solvent: cyclohexane) and a special developer (MEK
Uses a developer containing a main component) and a special rinsing solution (a rinsing solution containing MIBK as a main component)
Patterning and post-baking at 180 ° C for 30 minutes.
Three color stripes of R (red), G (green) and B (blue) in the same manner as in the first embodiment.
A filter was obtained.       [0068]   The color filter thus obtained was compared with the case of Example 1 with resin and face.
Because it is formed using a colored resin material that has a low affinity for
The surface flatness was poor.   Further, the color filter was inferior in durability due to the characteristics of the resin.       [0069]   Further, using the obtained color filter substrate, the same method as in Example 1 was used.
When a dielectric liquid crystal element was formed and observed with a crossed Nicols polarizing microscope,
Poorly-aligned portions arising from portions with poor surface flatness were observed, affecting display characteristics.
Was. The display contrast at this time is the display contrast obtained in the first embodiment.
Was reduced 0.4 times.       [0070]   Comparative Example 3   The photosensitive polyimide resin used for the colored resin material of Example 1 was replaced with a far ultraviolet negative.
ODUR-110WR (trade name, manufactured by Tokyo Ohka Co., Ltd., solvent:
After exposure with far-ultraviolet light, use a dedicated developer and rinse
Example 1 except turning and performing post-baking at 180 ° C for 30 minutes
In the same manner as in 1, the three-color stripe color fill of R (red), G (green), and B (blue)
I got it.       [0071]   The color filter thus obtained was compared with the case of Example 1 with resin and face.
Because it is formed using a colored resin material that has a low affinity for
The surface flatness was poor.   Further, the color filter was inferior in durability due to the characteristics of the resin.       [0072]   Further, using the obtained color filter substrate, the same method as in Example 1 was used.
When a dielectric liquid crystal element was formed and observed with a crossed Nicols polarizing microscope,
Poorly-aligned portions arising from portions with poor surface flatness were observed, affecting display characteristics.
Was. The display contrast at this time is the display contrast obtained in the first embodiment.
Was reduced by a factor of 0.5.       [0073]   Comparative Example 4   The photosensitive polyimide resin used for the colored resin material of Example 1 was replaced with a photosensitive PVA resin.
Diazo compound with FR-14 (trade name, manufactured by Fuji Pharmaceutical Co., Ltd., solvent: water)
In place of the addition of the substance, patterning by development with water and rinsing, 120 ° C,
R (red) in the same manner as in Example 1 except that post-baking for 30 minutes was performed.
, G (green) and B (blue).       [0074]   The color filter thus obtained was compared with the case of Example 1 with resin and face.
Because it is formed using a colored resin material that has a low affinity for
The surface flatness was poor.   Further, the color filter was inferior in durability due to the characteristics of the resin.       [0075]   Further, using the obtained color filter substrate, the same method as in Example 1 was used.
When a dielectric liquid crystal element was formed and observed with a crossed Nicols polarizing microscope,
Poorly-aligned portions arising from portions with poor surface flatness were observed, affecting display characteristics.
Was. The display contrast at this time is the display contrast obtained in the first embodiment.
To 0.4 times.       [0076]   Comparative Example 5   In Example 1, instead of using a photosensitive colored polyimide resin, a non-photosensitive
A three-color filter was formed using a colored polyimide resin.       [0077]   That is, a blue colored polyimide resin material [Heliogen Blue (
Heliogen Blue) L7080 (trade name, manufactured by BASF, CI.
No. 74160) was changed to Semico Fine SP-910 (trade name, manufactured by Toray Industries, Inc., solid content)
= 22%, pigment: polymer = 1: 2)).
It was applied to a thickness of 2.0 μm by a pinner coating method. Next, the colored resin layer is
After drying at 50 ° C. for 30 minutes, it was heated at 200 ° C. for 30 minutes.       [0078]   Then, a positive resist [OFPR-2 (trade name, manufactured by Tokyo Ohkasha Co., Ltd.) is formed on the blue layer.
)] Is applied by spinner, and after pre-baking at 80 ° C. for 20 minutes, it is to be formed.
Exposure was performed with a high-pressure mercury lamp through a pattern mask corresponding to the pattern shape.       [0079]   After the exposure, the resist is developed with an alkaline developer and the blue layer is etched.
Followed by stripping the resist with acetone and heating at 250 ° C for 30 minutes
By firing, a blue colored resin film having a pattern shape was formed.       [0080]   Next, on the glass substrate on which the blue coloring pattern is formed, a green color is formed as a second color.
Color polyimide resin material [Lionol Green 6Y
K (trade name, manufactured by Toyo Ink Co., Ltd., CI No. 74265) (Trade name, manufactured by Toray Industries, solid content = 22%, pigment: polymer = 1: 2 blended)
Green colored pattern in the same manner as described above except that
Was formed at a predetermined position on the substrate.       [0081]   Further, on the substrate on which the blue and green patterns are formed, a third
As the color, a red colored polyimide resin material [Irgazin Red (Irgazin Red)
  Red) BPT (trade name, manufactured by Ciba-Geigy), C.I.
I. No. 71127) was replaced by Semicofine (trade name, manufactured by Toray Industries, solid content = 22%)
, Pigment: polymer = 1: 2)).
Forms a red colored pattern at a predetermined position on the substrate in the same manner as
Three color striped color filters of red), G (green) and B (blue) were obtained.       [0082]   The color filter thus obtained was compared with the case of Example 1 with resin and face.
Because it is formed using a colored resin material that has a low affinity for
The surface flatness was poor.       [0083]   Further, the color filter was inferior in transparency due to the characteristics of the resin. In addition,
Since a resist step for turning is required for each color formation, a very complicated process is required.
Seth was inferior in productivity.       [0084]   Subsequently, using the obtained color filter substrate, the same method as in Example 1 was used.
When a dielectric liquid crystal element was formed and observed with a crossed Nicols polarizing microscope,
Poorly-aligned portions arising from portions with poor surface flatness were observed, affecting display characteristics.
Was. The display contrast at this time is the display contrast obtained in the first embodiment.
To 0.3 times.       [0085]     【The invention's effect】   As described above, according to the present invention, the difference in film thickness of the color filter layer on the substrate
And the pixel interval α (μm) is positioned so that it falls within the range of 0 ≦ α ≦ 5 μm. Color, by providing a light-shielding layer, a protective film, and a planarizing film as needed.
It is possible to eliminate minute steps that occur between each pixel of the filter,
Liquid crystal element that can prevent the occurrence of cracks and sufficiently exhibit the characteristics of ferroelectric liquid crystal
Can be provided.       [0086]   Furthermore, according to the present invention, it has excellent mechanical strength, and has heat resistance, light resistance,
A color filter part having a fine pattern with excellent properties such as
It can be manufactured by the manufacturing process, and the performance as a color ferroelectric liquid crystal device
Can be easily provided.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view showing a basic configuration of a ferroelectric liquid crystal device according to the present invention. FIG. 2 is a perspective view schematically showing a ferroelectric liquid crystal used in the present invention. FIG. 3 is a perspective view schematically showing a ferroelectric liquid crystal used in the present invention. FIG. 4 is a sectional view of a conventional ferroelectric liquid crystal element. FIG. 5 is a schematic explanatory view showing a state of an alignment defect appearing in a conventional ferroelectric liquid crystal element. FIG. 6 is a process chart showing a color pixel forming process of the present invention. [Description of Signs] 1,40 Ferroelectric liquid crystal element 2,3,41,42,61 Substrate 4,47 Ferroelectric liquid crystal 5,6,43,44 Transparent electrode 7,8,45,46 Alignment control film 9 , 48,68 Protective film (planarization film) 10,67 Light shielding layer

Claims (1)

Claims: 1. A polyimide resin having a photosensitive group in a molecule, having a light transmittance of 90% or more in a wavelength region of 400 nm to 700 nm, and curing at a temperature of 200 ° C. or less; A color filter substrate having a substantially uniform film thickness color filter having a coloring resin comprising a coloring material dispersed in the polyimide resin on the substrate, and an interval α between the color filters of adjacent pixels. And the interval α is 0 μm <
α ≦ 5 μm, and the color filter and the interval α
A protective layer is uniformly formed, and the surface of the protective layer on the color filter and the space α
A color filter substrate , wherein a step formed between the protective layer and the surface is set to 1000 ° or less, and a transparent electrode having a pattern shape is provided on the protective layer . 2. A liquid crystal element having a chiral smectic liquid crystal sandwiched between a pair of substrates and a color filter on at least one substrate, wherein the color filter has a photosensitive group in a molecule and has a wavelength of 400 nm to 700 nm. It has a red resin, a blue resin and a green resin, which have a light transmittance of 90% or more in a wavelength range of, and which is cured at a temperature of 200 ° C. or less, and a coloring material dispersed in the polyimide resin. The thickness of the color filter is substantially uniform, and there is an interval α between the color filters of adjacent pixels , and the interval α is set to 0 μm <α ≦ 5 μm.
And a protective layer is uniformly formed on the color filter and the space α.
Formed between the surface of the protective layer on the color filter and the surface of the protective layer on the space α.
A liquid crystal device characterized in that a step to be formed is set to 1000 ° or less, and a transparent electrode having a pattern is provided on the protective layer .