JPH04181219A - Ferroelectric liquid crystal element - Google Patents

Abstract

PURPOSE:To obtain the ferroelectric liquid crystal element having excellent display and driving characteristics by decreasing the surface roughness of the color filters of respective picture elements having the smaller film thickness and nearly equaling the threshold values of the respective picture elements. CONSTITUTION:A ferroelectric liquid crystal 4 is crimped between substrates 2 and 3 and patterned transparent electrodes 5, 6 are disposed on the respective substrates 2, 3. Orientation control films 7, 8 are formed thereon. The color filters of red R, green G, blue B are so formed as to have desired spectral characteristics. The surfaces of the color filters are previously controlled with respective to the difference in the film thicknesses by each color generated on account of the coating process to eliminate the differences in the threshold characteristics generated from the differences in the thicknesses of the liquid crystal layers by each color in order to obtain the desired spectral characteristics. Namely, the surface roughness is increased (R>G>B) in order of the larger film thicknesses of the color filters (R>G>B) and the threshold characteristic differences generated from the thicknesses of the liquid crystal layers by each color (thicker order: B>G>R) are corrected. The threshold characteristics of the respective picture elements are nearly equaled in this way.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to ferroelectric liquid crystal elements such as liquid crystal display elements and liquid crystal-optical shutter arrays, and more specifically relates to ferroelectric liquid crystal elements such as liquid crystal display elements and liquid crystal optical shutter arrays. The present invention relates to a ferroelectric liquid crystal element with improved display and driving characteristics by improving differences in threshold characteristics.

[Prior Art] As a conventional liquid crystal element, for example, M-Shut (M,
5chadt) and Double Helfrich (W,
“Applied Physics Letters” by He1frich
Letters” Volume 18, No. 4 (published February 15, 1971), pp. 127-128 “Voltage Dependant Optical Activity”
・Of a Twisted Nematic Liquid Crystal (“Voltage Dependent 0
ptical Activity of a Twist
ed Nematic Liquid Crysta1
Twisted nematic (twist
(ednematic) liquid crystal is known. This TN liquid crystal has a problem in that crosstalk occurs during time-division driving using a matrix electrode structure with high pixel density, so the number of pixels is limited.

Furthermore, a display element is known in which a switching element using a thin film transistor is connected to each pixel, and each pixel is switched. However, the process of forming the thin film transistor on the substrate is extremely complicated, and the display element has a large area. There are some problems that make it difficult to create.

As a solution to these problems, Clark (C1
A ferroelectric liquid crystal device has been proposed by Ark et al. in US Pat. No. 4,367,924.

FIG. 2 schematically depicts an example of a cell for explaining the operation of a ferroelectric liquid crystal. 21a and 21b are Inz
O3,5nOz and ITO (Indium Tin 0x
A substrate coated with a transparent electrode made of a thin film such as
glass plate), between which a plurality of liquid crystal molecular layers 22 are oriented perpendicularly to the glass surface.
H" phase liquid crystal is sealed. The thick line 23 represents the liquid crystal molecule, and the liquid crystal molecule 23 has a dipole moment (P) 24 in the direction perpendicular to the molecule. When a voltage higher than a certain threshold is applied between the electrodes on the substrates 21a and 21b, the helical structure of the liquid crystal molecules 23 is unraveled, and all the dipole moments (P) 24 are directed in the direction of the electric field. The orientation direction of the liquid crystal molecules 23 can be changed.The liquid crystal molecules 23 have an elongated shape and exhibit refractive index anisotropy in the long axis direction and short axis direction. It is easily understood that by placing polarizers arranged in the same relationship, a liquid crystal optical modulation element whose optical characteristics change depending on the polarity of applied voltage can be obtained.

The liquid crystal cell preferably used in the ferroelectric liquid crystal element of the present invention can have a sufficiently thin thickness (for example, 10 μm or less). As the liquid crystal phase becomes thinner in this way, the helical structure of the liquid crystal molecules unwinds and becomes a non-helical structure even when no electric field is applied, as shown in Figure 3.
Its dipole moment Pa or pb is upward (34a)
or downward (34b). When an electric field Ea or Eb of a different polarity, which is equal to or higher than a certain threshold value, is applied to such a cell as shown in FIG. Accordingly, the liquid crystal molecules are oriented in either the first stable state 33a or the second stable state 33b.

As mentioned above, there are two advantages to using such a ferroelectric liquid crystal as an optical modulation element. The first is that the response speed is extremely fast, and the second is that the alignment of liquid crystal molecules has bistability. the second point, e.g.
To further explain with reference to the figure, when the electric field Ea is applied, the liquid crystal molecules are oriented in a first stable state 33a, and this state remains 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 a second stable state 33b and change their orientation, but they remain in this state even after the electric field is turned off. Further, as long as the applied electric field Ea does not exceed a certain threshold value, each orientation state is maintained. In order to effectively realize such fast response speed and bistability, it is preferable that the cell be as thin as possible.

In order for this ferroelectric liquid crystal element to exhibit predetermined driving characteristics, the ferroelectric liquid crystal placed between a pair of parallel substrates must
It is necessary that the molecules be arranged in such a state that conversion between the two stable states effectively occurs regardless of the state of application of the electric field. For example, in a ferroelectric liquid crystal having a chiral smectic phase, a layer of liquid crystal molecules in the chiral smectic phase is perpendicular to the substrate surface, thus forming a region (monodomain) in which the liquid crystal molecular axes are aligned almost parallel to the substrate surface. It is necessary to

FIG. 4 shows a cross-sectional view of a conventional ferroelectric liquid crystal element. That is, the conventional ferroelectric liquid crystal element 40 shown in FIG.
It has a pair of parallel substrates 41 and 42.
2 are provided with strip-shaped transparent electrodes 43 and 44 each forming a matrix electrode structure.

Generally, color filters are red (R), green (G), blue (
B) or other dyes or layers containing the same, but the thickness of each dye layer is different regardless of its formation method, so a difference of about 2000 lpm is formed. As a result, the thickness of the liquid crystal layer changes for each color due to the difference in the film thickness of the dye layer, resulting in uneven threshold preferential treatment in which driving cannot be performed with the same electric field strength.

In this way, on the surface in contact with the ferroelectric liquid crystal, each pixel has 200
If a film thickness difference of 0 Å or more exists, the threshold preference will differ for each pixel due to the film thickness difference, making it impossible to obtain uniform driving and display of the ferroelectric liquid crystal.

[Problems to be Solved by the Invention] The present inventors have discovered that the difference in film thickness for each pixel of a color filter causes unevenness in threshold preferential treatment for ferroelectric liquid crystals. was revealed through experiments.

An object of the present invention is to provide a ferroelectric liquid crystal element that can prevent the above-mentioned difference in threshold preference between pixels and provide uniform display with excellent drive characteristics.

[Means for Solving the Problems] The present inventors focused on the fact that the threshold preference of ferroelectric liquid crystals changes depending on the difference in the surface condition (surface roughness) of color filters, and We have discovered a ferroelectric liquid crystal element in which the difference in threshold preference resulting from the difference in film thickness between each pixel can be controlled by the difference in the surface condition of the color filter.

The ferroelectric liquid crystal element of the present invention is based on such knowledge, and more specifically, the thicker the liquid crystal layer is, the more
= The thinner the color filter layer is, the better the color filter's surface properties will be, and the liquid crystal will respond even in a small electric field. It is characterized by the fact that the thicker the film, the lower the surface properties of the color filter, and the application of a larger electric field controls the liquid crystal to respond, thereby making a difference in the threshold preferential treatment for each pixel. .

That is, the present invention provides a ferroelectric liquid crystal element in which a ferroelectric liquid crystal is sandwiched between a pair of parallel substrates on which transparent electrodes are formed, and a color filter is provided between at least one of the transparent electrodes and the substrate. This ferroelectric liquid crystal element is characterized in that the thinner the filter film is, the smaller the surface roughness is, and the threshold preferential characteristics of each pixel are made almost the same.

Hereinafter, the present invention will be explained based on the drawings.

FIG. 1 is a sectional view showing the basic structure of a ferroelectric liquid crystal element according to the present invention. In FIG. 1, a ferroelectric liquid crystal element 1 has substrates 2 and 3 made of transparent plates such as glass plates or plastic plates, and a ferroelectric liquid crystal 4 is sandwiched between them. Transparent electrodes 5 and 6 in a striped pattern forming a matrix electrode structure are provided on each substrate 2 and 3, and alignment control films 7 and 8 are formed on the transparent electrodes. Each of the R (red), G (green), and B (noble) color filters is formed with a coloring material concentration set in advance so as to have desired spectral characteristics.

On the other hand, if necessary, a light shielding layer 10 is formed in the recess between each color filter, and a protective film or a flattening film 9 is further formed thereon.

In the substrate with the above configuration, even if the film thickness is actively changed for each color in order to obtain the desired spectral characteristics, or even if the film thickness is set to be the same, the difference in film thickness for each color that occurs during the coating process. On the other hand, since the surface properties of the color filters are controlled in advance, it is possible to eliminate differences in threshold preferential treatment resulting from differences in the thickness of the liquid crystal layer for each color.

In other words, in the example shown in Figure 1, the surface roughness increases in descending order of the film thickness of the color filter (R>G>B), and the thickness of the liquid crystal layer for each color (thickest) increases. Order: B>
This corrects the threshold preferential difference resulting from G>R).

In the present invention, the difference in film thickness and the difference in surface roughness can be set arbitrarily, but it is preferable to apply them within a range that does not affect alignment defects of the ferroelectric liquid crystal. Specifically, it is desirable that the difference in film thickness of the color filter is 0.5 pm or less, preferably 0.3 ILm or less. Also, as the surface roughness of the color filter, the maximum roughness Rmax
It is desirable to control the value within a range of 0.5 em or less, preferably 0.3 gm or less.

The binder forming the colored resin film of the color filter in the present invention is an aromatic polyamide resin or polyimide resin having a photosensitive group in its molecule, especially in the visible light wavelength range (400 to 700 nm). It is preferable to use a material that does not have light absorption characteristics (light transmittance of about 90% or more). From this point of view, aromatic polyamide resins are particularly preferred.

In addition, the photosensitive group in the present invention may be an aromatic group having a photosensitive hydrocarbon unsaturated group as shown below (for example, (1) benzoic acid esters (in the formula R1 (2) Benzyl acrylates (3) Diphenyl ethers (In the formula, R2 is CHX=CY-CONH-, CH2=CY
-COO-(CH,) 2-OCO or CH2=CY-
(4) chalcone and other compound chains (in the formula, R3 represents H-, an alkyl group, or an alkoxy group).

Specific examples of aromatic polyamide resins and polyimide resins having these groups in the molecule include “Lisoko” P
Examples include "A-1000" (trade name, manufactured by Ube Industries, Ltd.) and "Lisoko PI-400" (trade name, manufactured by Ube Industries, Ltd.).

Generally, photosensitive resins used in photolithography processes vary depending on their chemical structure, but there are few that have excellent durability such as mechanical properties, heat resistance, light resistance, and solvent resistance. On the other hand, the photosensitive polyamide resin or polyimide resin of the present invention described above is a resin system with excellent durability in terms of chemical structure, and the durability of color filters formed using them is also very good. Become something. In particular, it exhibits excellent performance in terms of heat resistance during sputtering of transparent conductive films that are problematic as color filters for ferroelectric liquid crystal devices, and damage to color filters caused by inner spacers when assembling liquid crystal devices. .

The coloring material forming the colored resin layer of the color filter in the present invention is not particularly limited, as long as it can obtain desired spectral characteristics among organic pigments, inorganic pigments, dyes, etc.

In this case, each material can be used alone or as a mixture of some of these materials. However, when a dye is used, the performance of the color filter is controlled by the durability of the dye itself, but if the resin system of the present invention is used, a filter with superior performance compared to ordinary dyed color filters can be obtained. Formable. Therefore, in view of the color characteristics and various performances of the color filter, organic pigments are most preferable as the coloring material.

Organic pigments include azo pigments such as soluble azo, insoluble azo, condensed azo, phthalocyanine pigments,
and fused polycyclic pigments including indigo, anthraquinone, perylene, perinone, dioxazine, quinacridone, isoindolinone, phthalone, methine/azomethine, and other metal complex systems, or any number of these. A mixture of these is used.

As a method of controlling the surface roughness of the color filter in the present invention, a method of preparing a colored resin by changing the degree of dispersion of the above-mentioned coloring material for each color, or a method of preparing a colored resin by changing the degree of dispersion of the above-mentioned coloring material for each color, or using an arbitrary combination of the above-mentioned coloring material and transparent particles for each color. There are methods for preparing colored resins by dispersing them.

In this case, the transparent particles include SiO□ and Sin.

Ai) Inorganic fine particles such as zo3.5isN*, Taxes, or polyacrylic, polystyrene, polyamide.

Polyimide, polyurethane, polycarbonate.

One type or a mixture of two or more types selected from organic fine particles such as silicon-based particles can be used.

Although it depends on the degree of surface roughness to be controlled, it is generally desirable to use transparent particles having an average primary particle diameter of 500 Å or less, preferably 50 to 200 ILm.

In the present invention, the colored resin used to form the colored resin layer is prepared by adding about 10 to 50 wt% of each of the above colored materials having desired spectral characteristics to the above photosensitive polyamide or polyimide resin solution. , the above-mentioned transparency particles for adjusting the surface roughness corresponding to the threshold preferential difference resulting from the difference in film thickness are blended for each color in an arbitrary proportion of about 0 to 20 wt%, preferably 0 to 10 wt%,
After sufficient dispersion using ultrasonic waves or triple rolls, large particles are preferably removed using a filter of 1 gm or less.

The colored resin layer of the color filter of the present invention is formed by applying the colored resin onto a substrate using a coating device such as a spinner or a roll coater, and forming a pattern through a photolithography process, and the layer thickness is determined according to desired spectral characteristics. Although it is determined depending on the situation, it is usually about 0.5 to 5 gm, preferably about 0.5 to 1.5 lm.

If it is necessary to further increase the adhesion between the colored resin layer and the underlying substrate, either apply a thin layer of silane coupling agent or the like on the substrate and then form a colored resin pattern, or By forming a color filter using a material to which a small amount of a silane coupling agent or the like is added, a layer effect can be obtained.

The colored resin layer of the color filter of the present invention is itself made of a good material that has sufficient durability. In order to flatten the surface of the color filter to some extent, organic resin such as polyamide, polyimide, polyurethane, polycarbonate, silicone, etc., or 5iaN4. Sin□,
Sin, Aj) aos.

An inorganic film such as Ta2es can be provided as a protective film or a planarizing film by a spin cord coating method, a roll coating method, or a vapor deposition method. The thickness of the protective film 9 can determine the thickness of the ferroelectric liquid crystal 4, so it varies depending on the type of liquid crystal material and the required response speed. It is set in the range of 2 m to 20 m, preferably 0.5 m to 10 m.

Furthermore, in order to improve display characteristics, a light shielding layer can be provided by any of the following three methods.

(1) Carbon black, iron black, or graphite is added to the same photosensitive polyamino resin as that used to form the colored resin layer either on the glass substrate, on the colored resin pattern, or on the protective film or flattening film. , using a light-shielding resin in which light-shielding materials such as copper-chromium-based, copper-iron-manganese-based complex oxide pigments, or other metal powders with light-shielding ability are dispersed.
A method of forming a light-shielding pattern using a photolithography process to match the depressions between each pixel.

(2) A thin metal film such as chromium or aluminum with light-shielding ability is formed by vapor deposition or sputtering on either the glass substrate, the colored resin pattern, the protective film or the planarizing film, and the depressions between each pixel are A method of forming a light-shielding pattern by forming a resist mask and etching away the metal thin film on each pixel.

(3) When forming a colored resin pattern on a glass substrate, adjacent edges of each of the two colors (2 to
A method in which a light-shielding pattern is simultaneously formed by overlapping layers (approximately 151 Lm), and the protective film or flattening film is provided on the color filter layer in order to flatten the overlapping portion.

Examples of materials for the alignment control film used in the present invention include polyvinyl alcohol, polyimide, polyamideimide, polyester, polycarbonate, polyvinyl acecool, polyvinyl chloride, polyvinyl acetate, polyamide, polystyrene, cellulose resin, melamine resin, and urea. resins, acrylic resins, photosensitive polyimides, photosensitive polyamides, cyclic rubber photoresists, phenol novolac photoresists, electron beam photoresists (polymethyl methacrylate, epoxidized-1,4-polybutadiene, etc.), etc. It can be formed by selecting from. Although the alignment control film 7 depends on the film thickness of the ferroelectric liquid crystal, -10 people to lpm for boat fishing;
It is preferably set in a range of 100 to 3000 people.

Particularly suitable liquid crystal materials for use in the present invention are liquid crystals having bistability and ferroelectricity. Specifically, chiral smectic C phase (SmC
'), H phase (SmH"), I phase (SmI")
, J phase (SmJ”), K phase (SmK”),
G-phase (SmG'') or F-phase (SmF'') night crystals can be used.

Regarding this ferroelectric liquid crystal,
19
1975, Hexa (L-69) issue, ``Ferroelectric Liqui Sodo Crystals J (rFerroele
ctric Liquid CrystalsJ);
“Applied Fisi Socs Letters”
Lied Physics Letters”)1
980, No. 36 (11), “Submicro Second Bistiple Electroobtic Switching in Liquid Crystals” (rsubmi
cro 5econd B15table Elect
roopticSwitching in Liqui
d CrystalsJ) ; “Solid State Physics” 1981
No. 16 (141), ``Liquid Crystal'', etc., and the ferroelectric liquid crystal disclosed therein can be used in the present invention.

Specific examples of ferroelectric liquid crystals include decyloxybenzylidene-p'-amino-2-methylbutylcinnamate (DOBAMBC), hexyloxybenzylidene-p'-amino-2-chloropropylcinnamate (
HOBACPC), 4-o-(2-methyl)-butylresollylidene-4'-octylaniline (MBRAS)
can be mentioned.

When constructing an element using these materials, the element can be supported by a block or the like in which a heater is embedded, if necessary, in order to maintain the temperature at such a temperature that the liquid crystal compound enters the chiral smectic phase.

[For use] The ferroelectric liquid crystal element of the present invention is an element in which a ferroelectric liquid crystal is sandwiched between a pair of parallel substrates on which transparent electrodes are formed, and a color filter is provided between at least one of the transparent electrodes and the substrate. , the thinner the film thickness is, the smaller the surface roughness is due to the difference in film thickness caused by the color filter of each pixel. Therefore, the difference in electric field strength caused by the difference in the thickness of the liquid crystal layer is reduced By correcting based on the difference in ease of driving, it is possible to make the threshold preferential treatment of each pixel almost the same.

[Example] Hereinafter, the present invention will be explained in more detail with reference to Examples.

Embodiment 1 FIGS. 5(a) to 5(f) are process diagrams showing the process of forming color pixels of 83 colors, R and G.

First, on a Corning #7059 glass substrate 51, a blue colored resin material [
Heliogen Blue
L7080 (Product name, manufactured by BASF, C,1,
No. 74160) to PA-1000C (trade name, manufactured by Ube Industries, polymer content = 10%, solvent: N-methyl-
A photosensitive colored resin material prepared by dispersing 2-pyrrolidone in a pigment:bolimer=1=2 formulation] was applied to a film thickness of 1.3 m by a spinner coating method to form a colored resin layer 52. . (See FIG. 5(a)) Next, the colored resin layer 52 is prebaked at 80° C. for 10 minutes, and then exposed to light using a high-pressure mercury lamp through a photomask 53 corresponding to the pattern shape to be formed. did. (See FIG. 5(b)) After the exposure, as shown in FIG. 5(c), a special developer (N-methyl-2- After developing using ultrasonic waves in a developing solution containing pyrrolidone as the main component and processing with a special rinsing solution (for example, a rinsing solution containing isopropyl alcohol as the main component), the
Bost baking was performed for 0 minutes to form a blue patterned colored resin layer 54 having a patterned shape. (See FIG. 5(d)) Next, a green colored resin material [Lionol Green 6YK (m product name)] was applied as a second color onto the glass substrate on which the blue colored pattern was formed.

Toyo Ink Co., Ltd., C, 1, No. 74265) and 5iOz-based fine particles [AEROSIL (product name 1, manufactured by Nippon Aerosil Co., Ltd.) were combined with PA-1000C (product name, Ube Industries, Ltd., polymer content = 10%, solvent: N-methyl-2-
Pyrrolidone, pigment: Bolimer = 1; 2 combination, 5i02
In the same manner as above, except for using a photosensitive colored resin material prepared by dispersing it in microparticles (containing 0.5 wt%),
A green patterned colored resin layer 55 having a thickness of 1.51 mm was formed at a predetermined position on the substrate.

Furthermore, a red colored resin material [Irgazin Red BPT] was applied as a third color onto the substrate on which the blue and green patterns were formed in this way.
(Product name, manufactured by Ciba-Geigy).

C, 1, No. 71127) and 5iOz-based fine particles [
AEROSIL (product name 1 manufactured by Nippon Aerosil Co., Ltd.)]
A-1000C (product name, manufactured by Ube Industries, polymer content =
10%, solvent 2N-methyl-2-pyrrolidone, pigment:bolimer = 1:2 blend, 5102 series fine particles = 1.0w
A red patterned colored resin layer 56 with a film thickness of 1.7 pm was placed at a predetermined position on the substrate in the same manner as described above except that a photosensitive colored resin material prepared by dispersing in A colored pattern of three color stripes of R (red), G (green), and B (blue) was obtained. (See Figure 5(e)) Surface roughness (maximum roughness: RmaxJIS-
As a result of measuring the surface roughness of the patterned colored resin layer of each color using a stylus-type surface roughness meter (showing the value defined in BO601), the surface roughness of the patterned colored resin layer of each color was 0, 10 μm for blue, 10 μm for blue, and 10 μm for blue, respectively.
The values were 0.18 m for green and 0.30 m for red.

Next, on the glass substrate on which the three-color colored pattern was formed,
As a light shielding layer, a black colored resin material [carbon black (C
, 1, No. 77266) in PA-1000C (polymer content = 10%, pigment: polymer = 1 = 4 blend)] using the same method as above. A light shielding layer 57 having a light shielding pattern was formed to match the gap between each pixel.

On the color filter pattern obtained in this way,
A transparent resin material similar to that used for the colored resin material as the protective film or flattening film 58 [PA-1000C (trade name, manufactured by Ube Industries, Ltd., polymer content = 10%, solvent 2N-methyl-2-pyrrolidone)] Approximately 1.
It was formed with a film thickness of 0 pm. (See FIG. 5(f)) As described above, it was possible to form color filter substrates with different surface states for each color having different film thicknesses.

Specifically, in descending order of color filter film thickness (B<G
<R) A color filter substrate with good surface properties was formed.

Next, as shown in FIG. 1, a transparent electrode 5 was formed by forming an ITO film to a thickness of 500 mm by sputtering. On top of this, a polyimide forming solution 'ti' (Hitachi Chemical rPIQ J) was applied as an orientation control film 7 using a spinner rotating at 300 rpm and heated at 250° C. for 30 minutes to form a 2,000-layer polyimide film. Thereafter, the surface of this polyimide film was subjected to a rubbing treatment.

The thus formed color filter substrate and the opposing substrate 3 were bonded together to form a cell, and ferroelectric liquid crystal was injected and sealed to obtain a liquid crystal element. When this liquid crystal element was driven, the threshold characteristics for each color were almost the same, and excellent driving characteristics were obtained.

Comparative Example 1 A liquid crystal element was manufactured in the same manner as in Example 1 except that the SiO□-based fine particles were not used, and when it was driven, the threshold characteristics were different for each color.

In other words, the thinner the color filter is (B<
G<R), it did not drive unless a higher applied voltage was applied, and the drive characteristics were poor.

[Effects of the Invention] As explained above, according to the present invention, by first adjusting the surface roughness according to the film thickness of each color of the color filter layer on the substrate, differences in liquid crystal layer thickness can be avoided. It is possible to eliminate the differences in threshold characteristics for each color that occur, and to provide a ferroelectric liquid crystal element with excellent display and drive characteristics.

Furthermore, according to the present invention, it has excellent mechanical strength, and
Color filter parts with fine patterns that have excellent properties such as heat resistance, light resistance, and solvent resistance can be manufactured using a simple manufacturing process, and have excellent performance as color ferroelectric liquid crystal elements. can be provided easily.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing the basic structure of a ferroelectric liquid crystal element according to the present invention, FIGS. 2 and 3 are perspective views schematically showing the ferroelectric liquid crystal used in the present invention, and FIG. are a cross-sectional view of a conventional ferroelectric liquid crystal element and FIGS. 5(a) to (f).
FIG. 2 is a process diagram showing the process of forming color pixels according to the present invention. 1.40... Ferroelectric liquid crystal element 2, 3.41.42.51... Substrate 4.47... Ferroelectric liquid crystal 5, 6.43.44... Transparent electrode 7, 8. 45.46... Orientation control film 9, 48.58... Protective film (flattening film) 10, 57.
...Light shielding layer 52...Colored resin layer 52a...Photocured portion 53...Photomask

Claims (2)

[Claims] (1) A ferroelectric liquid crystal element in which a ferroelectric liquid crystal is sandwiched between a pair of parallel substrates on which transparent electrodes are formed, and a color filter is provided between at least one of the transparent electrodes and the substrate,
A ferroelectric liquid crystal device characterized in that the thinner the film thickness of the color filter of each pixel, the smaller the surface roughness, and the threshold characteristics of each pixel are made almost the same. (2) The strong color filter according to claim 1, wherein the color filter is formed by a photolithography process of a colored resin obtained by dispersing a coloring material in an aromatic polyamide resin or a polyimide resin having a photosensitive group in the molecule. Dielectric liquid crystal element.