JPS60237441A - Formation of colored image - Google Patents

Abstract

PURPOSE:To obtain a transparent colored image superior in heat and light resistances without using any dye preventing film by exposing a photosensitive polyimide film contg. a pigment specified in size distribution formed on a support, developing it to form a colored image, and repeating it to form images having plural color patterns. CONSTITUTION:The photosensitive polyimide (P1) film 2 contg. a dispersed pigment having a distribution of particles of >=1mum diameter amounting to <=10wt% of the total particles, is formed on the support 1, then, the P1 film 2 is patternwise exposed and developed to form a patternwise colored images 2a (red). When needed, this operation is repeated to form patternwise colored images 2a, 2b (green), and 2c (blue) having plural colors. A transparent electrically conductive film having a prescribed pattern is formed on the support 1 or on the images 2a-2c. It is desirable for obtaining better light transmittance to use the pigment having a size distribution of particles having >=1mum diameter amounting to <=5wt% of the total pigment particles and at the same time, a distribution of paticles having 0.01-0.7mum diameter amounting to >=30wt% of the total particles. As a result of such a constitution, the obtained transparent colored image is superior in heat and light resistances and need not form a dye preventing film.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a method for forming a colored image, and more specifically, to a method for forming a colored image.
It relates to a method for forming colored images used in color filters or stained glass installed in full-color liquid crystal display devices with built-in filters, color facsimiles, three-tube or single-tube color video cameras, solid-state color video cameras, etc.

[Technical background of the invention and its problems] In recent years, interest in home color video cameras has been rapidly increasing. A color video camera for red color is required to be small, lightweight, and inexpensive, and for this reason extremely fine stripes of two or more different hues are mounted on a transparent substrate. A single-tube color video camera is used, which has a color filter attached to the image pickup tube. For the same purpose, solid-state color video cameras have also been proposed in which a color filter is provided in direct contact with the light-receiving surface of a solid-state image sensor of a color video camera.

On the other hand, there is growing interest in colorizing images displayed in liquid crystal display devices, and one method for achieving this goal is to fill a liquid crystal material between a pair of parallel transparent electrodes, and to spread the transparent electrodes into discontinuous fine particles. In addition to dividing the transparent electrode into areas, a color selected from red, blue, and green is alternately provided in each of the fine areas on the transparent electrode in a pattern, or a color filter is formed on the substrate. A method has been proposed in which a transparent electrode is provided after the process is completed.

Color filters used in color video cameras, color liquid crystal display devices, etc. are made by providing extremely fine areas colored in two or more different hues on a transparent substrate or solid-state imaging element. is formed by.

Generally, in order to color a minute area with two or more colors having different hues, a photosensitive resin that can form a transparent colored image (pixel) is used.

Conventionally, in order to form two or more types of transparent colored images using photosensitive resins, first, a hydrophilic resin such as polyvinyl alcohol, polyvinylpyrrolidone, gelatin, casein, or griux is coated with dichromate or chromium as a photosensitive resin. A photosensitive resin to which an acid salt or a diazo compound is added is coated on a support such as a transparent substrate or a solid-state imaging device to form a transparent photosensitive resin layer. Next, a mask with a lobe pattern in a predetermined shape is placed on this photosensitive resin layer, and exposed and developed to form a first resin layer, and this first resin layer is dyed with a desired dye. A first transparent colored image is formed. Next, in order to prevent dye migration, a transparent resist dyeing resin film made of a hydrophobic resin is formed on this first transparent colored image, and then the same process as that for forming the first transparent colored image is performed. to form a second transparent colored image. By repeating the above operations, a transparent colored image colored in two or more colors is formed on the support.

However, according to the above method, the photosensitive resin layer must be patterned into a predetermined shape for each color, and if a transparent resist dyeing resin film is not formed for each color, multiple colors can be transparent. Since an image cannot be provided, the manufacturing process is extremely complicated. Furthermore, some color filters may be heated during use, but the above method uses dyes to create transparent images in each color, so there is a limit to the heat resistance or light resistance of the color filters. was not satisfactory in this respect.

Furthermore, according to the above method, variations occur in the thickness of the colored image layer provided on the transparent substrate, and when this colored image is used in a color liquid crystal display device, for example, voltage-induced phenomena occur for each color. There was a problem in that variations occurred.

[Object of the invention and its outline]

The present invention aims to solve all of the above-mentioned drawbacks and problems associated with the prior art, and has the following objects.

(a) When transparent colored images of two or more colors are provided adjacently on a support, such as in a color filter, there is no need to form a transparent resist dyeing resin film for each color. To provide a method for forming a transparent colored image, which simplifies the manufacturing process.

(1)) To provide a method for forming a transparent colored image that can provide a transparent colored image with excellent heat resistance and light resistance.

(C) To provide a method for forming a transparent colored image with small variations in the thickness of a colored image layer and, therefore, with small variations in voltage drop when used in a liquid crystal display device.

In order to achieve the above object, in the method for forming a colored image according to the present invention, particles having a particle size of 1 μm or more are formed on a support, and one of the total particles is
A photosensitive polyimide film is formed in which a pigment having a particle size distribution of 0% or less is dispersed, and then this photosensitive polyimide film is exposed to light in a pattern, and then developed to form a patterned colored image. Furthermore, the above-mentioned operation is repeated a plurality of times as necessary to form colored images in a plurality of colors in a pattern.

Colored articles made by depositing a certain type of pigment on a support have been known in the past, but the particle size of the pigment used there is significantly larger than that of the present invention, resulting in poor transparency. However, it is only used for purposes such as masking, and even if it were used for color filters, it would not be possible to obtain a product with sufficient sensitivity due to its low transmittance.

Furthermore, it was not known until now that the transparency of the colored image obtained could be improved by controlling the particle size of the pigment and the platform for forming the resin layer on the support. . The present invention [Well, if the colored layer is formed by a photosensitive polyimide film in which pigments having a specific particle size distribution are dispersed, the decrease in light transmittance due to light scattering can be suppressed, and the coloring obtained can be suppressed. This is based on the discovery that the transparency of the image is sufficiently high for practical use.

[Detailed description of the invention]

Hereinafter, a method for forming a colored image according to the present invention will be explained with reference to the drawings.

Figures (a) to (d) are cross-sectional process diagrams showing a method for forming a colored image according to the present invention. In the method of the present invention, first, as shown in FIG.
[1- Form a film with a thickness of 0.2 to 3.0 μm by a coating method, a dipping method, a spin coating method, a spray method, or the like.

The support 1 includes transparent supports such as soda lime glass, Pyrex glass, quartz glass, synthetic quartz plates, optical resin plates, and transparent resin films (for example, polyester films), as well as active elements such as cathode ray tube substrates and TFTs, Opaque supports such as color facsimile sensors, solid layer imaging elements, etc. may be used. Furthermore, the colored image according to the present invention can be formed on a patterned transparent electrode provided on a support, and in this sense, a transparent electrode can also be used as the support 1. The transparent colored image created by the present invention,
When used in a color liquid crystal display device, the support and the conductive film are preferably transparent.

As used herein, the term "pigment" refers to a colored powder that is soluble in organic solvents or water, and includes both organic pigments and inorganic pigments. Note that some kinds of dyes (for example, disperse dyes) are poorly soluble in organic solvents or water, and these kinds of dyes can be used as "pigments" in the present invention.

Examples of organic pigments include azo lake type, insoluble azo type, integrated azo type, phthalocyanine type, main nacridone type, dioxazine type, isoindolinone type, anthraquinone type, perinone type, thioindico type, perylene type, or pigments of these types. Mixtures can be used.

As the inorganic pigment, Miloli blue, iron oxide, cobalt purple, manganese purple, ultramarine blue, navy blue, cobalt blue, cerulean blue, goliazine, emerald green, cobalt green, etc. can be used.

In the above pigment, particles with a particle size of 1 μm or more account for 10 of the total pigment particles.
It is preferable to have a particle size distribution of less than Shigekawa, preferably less than 5% by weight, more preferably less than 2% by weight. Particles with a particle size of 1 μm or more account for 10 of the total pigment particles.
If it exceeds % by weight, it is not preferable because the light transmittance decreases due to light scattering. At the same time, the vine pigment used in the present invention has a particle size of 0.01 to 0.7 μm, preferably 0.
．． Particles with a diameter of 0.01 to 0.3 μm account for at least 20% by weight of the total pigment particles, preferably at least 30% by weight, and more preferably at least 50% by weight.
It is desirable to have a particle size distribution that is greater than or equal to % by weight.

The photosensitive polyimide resin in which the above pigment is dispersed includes:
Examples include polyimide composed of imide bonds, polyamideimide composed of amide bonds and imide bonds, and polyesterimide composed of ester bonds and imide bonds. Furthermore, for example, Tokuko Sho 55-1
A polyimide prepared by dehydrating and ring-closing a condensate of pyromellitic anhydride and 4,4'-diaminodiphenyl ether, etc., as disclosed in Publication No. 0181, may also be used. After forming the photosensitive polyimide coating 2 with pigments distributed on the support 1 as described above, this photosensitive polyimide coating 2
is patterned into a predetermined shape according to a conventional method to obtain colored image 2.
a (for example, red) (Figure (b)). The patterning method involves irradiating the photosensitive polyimide film formed on the support with ultraviolet rays through a mask with a predetermined pattern, leaving an insolubilized pattern behind, and dissolving and removing the non-exposed areas. A method is used in which the exposed area is etched, and if necessary, this is dried by heating or the like and further hardened.

Next, in the same manner as above, a colored image 2b (for example, green) having a different color from the colored image 2a is set adjacent to the colored image 2a (see Figure (C)). Accordingly, a colored image 2c having a different color from the colored images 2a and 2b (for example, blue) is placed between the colored images 2a and 2b in the same manner as described above.
Jru (Figure (d)).

Note that, if necessary, it is also possible to print a number of colored images of more than three colors on the support.

When the colored image according to the present invention is used as a color filter for a liquid crystal display, for example, it is preferable to perform an alignment treatment by rubbing a polyimide film in which a pigment having a specific particle size is dispersed with a cloth or the like. . In such cases, the polyimide film not only functions as a colored layer but also functions as an alignment layer.

The transparent colored image produced by the present invention has a temperature of 20'0'C.
Pi! Even if it is heat-treated for about 2 hours at a temperature of 30°C, its spectral transmittance characteristics hardly change, and it has excellent heat resistance. In addition, colored images dyed with general dyes are
The color fades significantly when heated at 200'C for several minutes.

Moreover, the transparent colored image obtained by the present invention is
No change in hue was observed even after 30 hours of light irradiation with a Bon Arc lamp, indicating excellent light resistance.

In addition, when the colored image according to the present invention is used in a liquid crystal display device, a transparent conductive film and an alignment layer may be further provided on the polyimide colored image, and a polarizing plate may be further provided on the light source side of the support. Good too.

〔Effect of the invention〕

The method for forming a colored image according to the present invention is formed by pattern exposure of a photosensitive polyimide film in which pigments having a specific particle size distribution are dispersed, and therefore the following effects are achieved.

(a) When placing a multi-colored colored image on a support,
There is no need to form a transparent resist dyeing resin film for each color,
Therefore, the manufacturing process can be simplified.

(b) Colored images with excellent heat resistance and light resistance can be obtained. (C) Variations in the thickness of the colored image layer are small, and therefore variations in voltage drop when used in a liquid crystal display device are small.

(d) When used in a liquid crystal display device, it is possible to use a polyimide name color image as an alignment layer to function (one thing is that the device can be simplified).

EXAMPLES The present invention will be explained below with reference to Examples, but the present invention is not limited to these Examples.

1 part by weight of Rei Tomotane Yukuro Monotal Red BRN (red pigment manufactured by Rei Jiha Geigy) and 17% solid content of photosensitive polyimide.
7 oto:-su (manufactured by Toshishiku Co., Ltd.) was dissolved in N-methyl-2-pyrrolidone ()4tonis:pikulidone-1=3 (weight ratio)) solution 10 parts and mix,
The resulting mixture was mixed into three bottles [1-1 liters after dispersion].
00 rpm T'' centrifugation and filtration with a 1 μm glass filter.

Next, the obtained red photosensitive resin composition was spin coated onto a 1 mm thick Pyrex glass substrate to a film thickness of 1 μm.
It was dried at 80° C. for 30 minutes, and exposed in close contact with an ultra-high pressure mercury lamp through a mask of a predetermined shape.

Next, the pattern-exposed photosensitive resin composition was spray developed to selectively dissolve and remove non-exposed areas, and then heated at 170° C. for 60 minutes to form a red image.

Next, 10 parts by weight of the photosensitive polyimide solution was added and mixed with 1 part by weight of Onol Green 2Y-301 (green pigment manufactured by Toyo Ink Mfg. Co., Ltd.), and the resulting mixture was ground and dispersed using three rolls. After that, the mixture was centrifuged at 120 rpm and filtered through a 1 μm glass filter. Next, the obtained green photosensitive resin composition was spin-coated to a film thickness of 1 μm over the entire surface of the glass substrate on which the red transparent image was provided, and dried at 80° C. for 30 minutes. After precisely aligning the mask, contact exposure was performed, unexposed areas were selectively dissolved and removed by development, and baking was performed at 170° C. for 60 minutes to form a green image adjacent to the red image.

In the same manner, 10 parts by weight of the photosensitive polyimide solution and 1 part by weight of Chromo Blue A3R (blue pigment manufactured by Ciba Geigi) were added and mixed, and the blued mixture was centrifugally dispersed at 4u120 Orpm using three rolls for kneading and dispersion. , and filtered through a 1 μm glass filter.

Next, the obtained blue photosensitive resin composition was added to the above red photosensitive resin composition.
: 1 on the entire surface of the glass substrate with a dark green transparent image
After spin coating with a film thickness of μm and drying at 80°C for 30 minutes,
A color image according to the present invention is obtained by precisely aligning a prescribed mask, closely exposing it to light, selectively dissolving and removing non-exposed areas through development, and drying to form a blue image adjacent to the above-mentioned green image. was formed.

On the colored image obtained in this way, a transparent ¥4 electrical film of In2O3 (5% 5N02) was applied to a film thickness of 800 nm by low-temperature sputtering, and then polyimide was coated on this to a film thickness of 1000 nm. After that, a rubbing treatment was performed and the electrode was combined with a counter electrode. Next, a cell was assembled by injecting liquid crystal, and when applied to a full-color liquid crystal display device in which a colored image was formed inside the cell, excellent characteristics were obtained.

In addition, the particle size distribution of the pigment in the red image is calculated by Coutler
When analyzed using an N4 submicron particle analyzer, the average particle size was 0.3 μm, and particles with a particle size of 0.5 μm or more accounted for 3% or less of the total particles. Similarly, when the particle size distribution of the pigment in the green image and the blue image was analyzed, the average particle size was 0.3 μm and 0.5 μm, respectively.
Particles having a particle size of μm or more accounted for 3% or less of the total particles.

Example 2 After forming a film of S:O2 to a film thickness of 1000 mm on a transparent support made of 1 mm thick Sodarum glass by sputtering method, I
A transparent conductive film was formed by sputtering n2O3 (5wt% 5no2) to a thickness of 800 mm. Next, apply a positive resist, FHPR (manufactured by Fuji Pharmaceutical Co., Ltd.),
After drying, contact lighting was applied using a mask with a predetermined pattern shape, development was performed, and after baking, the transparent conductive film was etched with an iron chloride solution, the resist was peeled off, and a transparent electrode was patterned into a predetermined shape.

Next, a colored image was formed on the transparent electrode in the same manner as in Example 1.

In other words, 1 part by weight of chromophthal red BRN (red pigment manufactured by Ciba Geigy) and 1 part by weight of photosensitive polyimide have a solid content of 1 part by weight.
7% 7Otnis (manufactured by Toshiku Co., Ltd.) was added to N-methyl-2.
- 10 parts by weight of a solution obtained by dissolving in pyrrolidone (Photonice: Pi(]]lidone-1-3 weight ratio), and the resulting mixture was kneaded and dispersed with three rolls, then 1
It was centrifuged at 20 rpm and passed through a 1 μm glass filter. Next, 1 q of the red photosensitive resin composition was spin-coated onto a part of the transparent electrode arranged in a pattern to a thickness of 1 μm, dried at 80° C. for 30 minutes, and coated through a mask of a predetermined shape. Close-contact exposure was performed using an ultra-high pressure mercury lamp. Next, the pattern-exposed photosensitive resin composition was developed by spraying, and after selectively dissolving and removing the non-exposed areas,
Heated for 0 minutes to form a red image.

Next, 10 parts by weight of the photosensitive polyimide solution was added and mixed with 6 parts of Onol Green 2Y-301 (green pigment manufactured by Toyo Ink Mfg. Co., Ltd.), and the resulting mixture was kneaded with three rolls. After being dispersed, the mixture was centrifuged at 1200 rpm and filtered through a 1 μm glass filter. Next, the obtained green photosensitive resin composition was spin-coated to a thickness of 1 μm (D) on a part of the patterned transparent electrode on which no red image was provided, and after drying at 80° C. for 30 minutes, After precisely aligning the mask, contact exposure is performed, the unexposed area is selectively dissolved and removed by development, and baked at 170°C for 60 minutes to form a green image adjacent to the red ii!8i@ above. did.

In the same manner, 10 parts of the photosensitive polyimide solution and 1 part by weight of Chromo Blue A3R (blue pigment manufactured by Ciba-Geigi) were added and mixed, and the resulting mixture was ground and dispersed in a three-kiss O-ru, and then centrifuged at 120 rpm. It was separated and filtered through a 1 μm glass filter.

Next, the obtained blue photosensitive resin composition was spin-coated to a film thickness of 1 μm onto the patterned transparent electrode in which no red image or green image was provided, and after drying at 80°C for 30 minutes, a predetermined pattern was applied. The colored image of the present invention was formed by precisely aligning the mask, contact exposure, developing, selectively dissolving and removing non-exposed areas, and drying to form a blue image adjacent to the green image. .

The surface of the colored image thus obtained was rubbed, combined with a counter electrode, and a cell was assembled by injecting liquid crystal to create a full-color liquid crystal display device with a colored image formed inside the cell. , excellent characteristics are 1
I was pissed.

In addition, the particle size distribution of the pigment in the red image is calculated by Coutler
J:ri analysis with N4 submicron particle analyzer 1
= However, the average particle size is 0.3 μm (..., 0.5 μm
Particles with a particle size of m or more accounted for 3% or less of all particles. Similarly, when the particle size distribution of Face 1i+ in green and blue images was analyzed, the average particle size was 0.3 μm, and particles with a particle size of 0.5 μm or more accounted for 3% or less of the total particles. there were.

[Brief explanation of the drawing]

Figures (a) to (d) are cross-sectional views showing each step of the method for forming a colored image according to the present invention. 1...Support, 2...Color image made of polyimide. Applicant's agent Inomata Qing Procedural Amendment (Bubin) March 1985/j IEI Commissioner of the Patent Office Manabu Shiga 1 Indication of the case 1982 Patent Application No. 93716 2 Name of the invention Method for forming colored images 3 Relationship with the case of the person making the amendment Patent ¥1 applicant (289) Dai Nippon Printing Co., Ltd. 4 agent July 11, 1980 (Shipping date: 1981 is the 31st day of the month) 6 Power of attorney subject to amendment , Drawings and Specification [Brief Description of Drawings, Column 1, 7'?in Correct Contents (1) Amend the power of attorney as shown in the attached sheet. (2) Amend the drawings as shown in the attached sheet, in red. (3 ) Akira 1111i1) Page 21, line 2, Figure 1 (a
) to (d) Correct J to [Fig. 1(a) to (d)]. First worker

Claims (1)

[Claims] 1. On the support, particles with a particle size of 1 μm or more account for 1 of all particles.
Forming a photosensitive polyimide film in which a pigment having a particle size distribution having a particle size distribution of 0 weight percent or less is dispersed, and then exposing this photosensitive polyimide film in a pattern and developing it to form a patterned colored image, A method for forming a six-color image, which further comprises repeating the above operation a plurality of times as necessary to form a colored image in a plurality of colors in a pattern. 2. The method according to claim 1, wherein a transparent conductive film is formed in a predetermined pattern on the support or the colored image. 3. The pigment has particles with a particle size of 1 μm or more that account for 5 of the total particles.
% by weight or less. 4. The pigment has particles with a particle size of 1 μm or more accounting for 10% by weight or less of the total particles, and has a particle size of 0.01 to 0.7 μm.
2. The method according to claim 1, wherein the particle size distribution is such that the particles of m are 20% by weight or more of the total particles. 5. The pigment has particles with a particle size of 1 μm or more that account for 5 of the total particles.
% by weight or less, and having a particle size distribution such that particles having a particle size of 0.01 to 0.7 μm account for 30% by weight or more of the total particles.