JPH1160988A - Resin-coated carbon black - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject product suitable for forming a black resist pattern, providing a photopolymerizable composition for forming the pattern, excellent in developing characteristics due to dispersibility in preparation of the composition, by coating carbon black with a polyfunctional epoxy resin and adjusting the gel fraction of the resin. SOLUTION: This carbon black is coated with a polyfunctional epoxy resin (e.g. glycidylamine type epoxy resin) and has 20-70% adjusted gel fraction of the polyfunctional epoxy resin of the coated layer. The ratio of the resin to the total of the carbon black and resin is generally selected from a range of 5-40 wt.%. The get fraction adjustment is carried out by using carbon black having >=15 mg/g total oxygen amount and the ratio of the total oxygen amount/the specific surface area of >=0.1 mg/m<2> , controlling a drying treatment temperature at 40-130 deg.C and regulating dehydrating conditions before the drying treatment and the arrangement of resin coated carbon black in a drying process, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin-coated carbon black, and more particularly, to a resin-coated carbon black suitably used, for example, for forming a black resist pattern.

[0002]

2. Description of the Related Art Carbon black is utilized for forming black resist patterns of various optical elements by utilizing its excellent blackness. For example, an optical color filter is an optical element suitably used for a color television, a liquid crystal display element, a camera, and the like, and is provided on a surface of a transparent substrate provided with a black resist pattern (black matrix).
Red, green and blue, three different hues, 10-150μ
It is manufactured by forming a color pattern such as an m-width stripe or mosaic with an accuracy of several μm.

[0003] The above-mentioned black matrix is formed by applying a photopolymerizable composition (coating liquid) in which carbon black is dispersed on a transparent substrate, and then performing each of heating, drying, image exposure, development and heat curing. You can do it.

[0004] The above-mentioned color filter is basically formed by applying a photopolymerizable composition (coating solution) in which red, green and blue materials are respectively dispersed on a surface on which a black matrix is formed, and heating the composition. It can be manufactured by sequentially performing drying, image exposure, development, and heat curing to form a pixel image of each color (Japanese Patent Laid-Open No. 2-902).
Counter electrode (transparent electrode) for driving color filter
Is formed in a thin film form on the pixel image surface from ITO or the like.

[0005] In actual production of a color filter, a top coat layer of polyamide, polyimide or the like is provided on the pixel image surface. Such a top coat layer is
It is required for the purpose of electrical insulation between the black matrix and the transparent electrode and enhancement of the smoothness of the pixel image surface.

The present inventors have proposed carbon black obtained by coating with a polyfunctional epoxy resin as the above-described carbon black for a black matrix (Japanese Patent Application Laid-Open No. 9-124969). Since such a resin-coated carbon black has an insulating surface, the use of the resin-coated carbon black can omit the top coat layer in the color filter. In particular, the above carbon black is uniformly coated with resin up to the microscopic portion of carbon black particles by using a polyfunctional epoxy resin having good wettability with the carbon black. Excellent as carbon black.

[0007] The black resist pattern is not limited to the above-described black matrix, but may be formed by applying a photopolymerizable composition (coating solution) in which carbon black is dispersed onto a transparent substrate, and then performing image exposure and development. It is formed by performing processing. Therefore, it is required that the above-mentioned coating solution has excellent developing characteristics in which carbon black is well dispersed. Here, the developing property means that at the time of image exposure, ultraviolet rays reach the lower part of the photopolymerizable composition layer on the transparent substrate and are sufficiently cured, and as a result, during development, a black profile having a good profile is obtained. It means that a resist pattern is formed. Such development characteristics can be evaluated based on the length of development time capable of maintaining a pattern having a constant line width during development. In other words, it means that the longer the developing time, the more the curing treatment by the ultraviolet rays is performed.

The above-mentioned carbon black obtained by coating with a polyfunctional epoxy resin has excellent properties in terms of insulation and the like, but the carbon black is dispersed in a photopolymerizable composition (coating solution). The dispersibility required in the preparation is not always sufficient.

[0009]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to be suitably used, for example, for forming a black resist pattern. It is an object of the present invention to provide a resin-coated carbon black which is excellent in dispersibility at the time of preparing a polymer composition and, as a result, can provide a photopolymer composition having excellent developing characteristics.

[0010]

As a result of various studies, the present inventors have found that the above-mentioned dispersibility of carbon black obtained by coating with a polyfunctional epoxy resin is determined by curing the polyfunctional epoxy resin of the coating layer. It has been found that the fully cured multifunctional epoxy resin coating layer, which is affected by the degree of the above, does not necessarily have sufficient wettability (dispersibility) with the components of the photopolymerizable composition.

The present invention has been completed on the basis of the above findings, and the gist of the present invention is that the polyfunctional epoxy resin coated with the polyfunctional epoxy resin has a gel fraction of 20 to 40.
70% of the resin-coated carbon black.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.
In the resin-coated carbon black of the present invention, a polyfunctional epoxy resin is used as a coating resin. As a specific example of the polyfunctional epoxy resin, a glycidylamine type epoxy resin (“Sumi Epoxy” ELM-1 manufactured by Sumitomo Chemical Co., Ltd.)
00, 120, 434, etc.), triphenyl glycidyl methane type epoxy resin (“Epicoat” 1032H50, 1032H60, etc., manufactured by Yuka Shell Epoxy), tetraphenylglycidylmethane type epoxy resin (“Epicoat” 1031, manufactured by Yuka Shell Epoxy) , Aminophenol type epoxy resin (“Epicoat” 154, 630 manufactured by Yuka Shell Epoxy), diamide diphenylmethane type epoxy resin (“Epicoat” 6 manufactured by Yuka Shell Epoxy)
04), phenol novolak type epoxy resin (“Epicoat” 152, manufactured by Yuka Shell Epoxy Co., Ltd.), orthocresol type epoxy resin (“Epicoat” 180S65, manufactured by Yuka Shell Epoxy Co., Ltd.), bisphenol A novolak type epoxy resin (Oiled Shell Epoxy) “Epicoat” 157S65, 157S70).

The resin-coated carbon black of the present invention is characterized in that the gel fraction of the polyfunctional epoxy resin in the coating layer is 20 to 7
The point is that it is adjusted to the range of 0%. When the gel fraction is less than 20%, the dispersibility during preparation of the photopolymerizable composition for forming a black resist pattern is excellent, but handling is difficult. In addition, when the gel fraction is less than 20%, the resin coating becomes insufficient, and as a result, the insulating property of the coating film formed from the photopolymerizable composition (coating solution) for forming a black resist pattern is reduced. On the other hand, when the gel fraction exceeds 70%,
Although the handleability is good, the effect of improving the dispersibility described above is not sufficient. The preferred range of the gel fraction is 40 to 6
0%. The amount of the resin coated on the carbon black is usually selected from the range of 5 to 40% by weight as the ratio of the resin to the total amount of the carbon black and the resin.

The above gel fraction is such that the total oxygen content is 15 m
g / g or more and the ratio of total oxygen content / specific surface area is 0.1 mg
/ M ² or more, and the drying temperature at the time of the coating treatment of the polyfunctional epoxy resin is 40 to 13
In addition to the temperature of 0 ° C., it can be easily obtained by appropriately adjusting the draining conditions before the drying treatment and the arrangement of the resin-coated carbon black in the drying step, particularly, the layer thickness (height) and the like. That is, the functional groups (-OH, = CO, -COOH, etc.) of the carbon black defined by the total oxygen amount are as follows:
It acts as a curing agent for epoxy resin. Therefore, the gel fraction of the polyfunctional epoxy resin can be controlled by adjusting the amount of the functional group defined by the above two parameters and various curing conditions (factors).

The above gel fraction can be measured, for example, as follows. First, 10 g of epoxy resin-coated carbon black and 200 ml of tetrahydrofuran (THF) were weighed and placed in a 500 ml beaker, and stirred with a stirrer for 5 hours to completely dissolve the dissolved components.
Filter through a 6 mesh wire mesh. Next, the obtained filtrate was dried at 70 ° C. to completely remove THF, and then the residue (T
(Epoxy resin eluted with HF). The amount of the epoxy resin in the epoxy resin-coated carbon black is denoted by A, the epoxy resin eluted with THF is denoted by B, and [(A-
B) / A] × 100 (%) is used to calculate the gel fraction.

The amount of the above oxygen functional group depends on the volatile composition,
The amount of groups and carbonyl groups is CO, the amount of carboxyl groups is C
O _TwoCan be quantified by each measurement. So
Then, the above total oxygen amount is CO and CO_TwoConverted from
Mean value. In addition, the above-mentioned volatile composition and amount are
Collect a certain amount of dry carbon black in a thermal sample tube
And 10^-2After reducing the pressure to mmHg,
Put the above sample tube in the electric furnace and remove it in 30 minutes
All volatiles are collected in a tank and used for gas chromatographic analysis.
Can be obtained by doing And CO and
And CO_TwoIs calculated based on the results of gas chromatography analysis.
You can do it.

The resin-coated carbon black of the present invention is suitably used particularly for forming a black resist pattern.
That is, it is suitably used as a photopolymerizable composition in which carbon black is dispersed. Such a photopolymerizable composition,
A photopolymerization initiation system that absorbs light to generate a radical together with carbon black, and a compound (ethylenic compound) having at least one addition-polymerizable ethylenically unsaturated double bond induced by the radical to induce polymerization. It contains. In addition, the above composition contains a dispersant and the like as necessary together with the organic polymer substance (binder resin). Then, the above composition is used as a coating solution prepared with a suitable solvent. The above-mentioned photopolymerization initiation system, ethylenic compound, organic polymer substance and solvent are appropriately selected according to the purpose of the black resist pattern. The resin-coated carbon black of the present invention exhibits excellent dispersibility during the preparation of the above-mentioned photopolymerizable composition, and gives a photopolymerizable composition having excellent developing characteristics.

In the method for manufacturing a color filter,
After applying the above-mentioned photopolymerizable composition on a transparent substrate, each process of heat drying, image exposure, development, and thermosetting is performed to form a black matrix.

As the coating device, a spinner, a wire bar, a flow coater, a die coater, a roll coater,
A spray or the like is used. The image exposure is performed by guiding a negative matrix pattern mask on the photopolymerizable layer and irradiating an ultraviolet or visible light source through the pattern mask. As the alkali developer, for example, an inorganic alkali agent such as sodium carbonate, potassium carbonate, sodium silicate, potassium silicate, sodium hydroxide, and potassium hydroxide is used.

[0020]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to the following examples unless it exceeds the gist of the present invention. In the following examples, the following materials were used.

(1) Preparation of resin-coated carbon black:
540 g of carbon black and 1450 g of pure water shown in Table 1
Was mixed with a homomixer at 6,000 rpm for 30 minutes to prepare a slurry. On the other hand, 60 g of "Epicoat 630" manufactured by Yuka Shell Epoxy Co., Ltd.
To prepare an epoxy resin solution. Transfer the above slurry to a container equipped with a screw type stirrer,
The above epoxy resin solution was added little by little under the stirring condition of rpm. After about 15 minutes, all of the carbon black dispersed in the water was transferred to the toluene side to become particles of about 1 mm. Next, after draining with a 60-mesh wire net for about 10 minutes, it was transferred to a stainless steel vat having a width of 30 cm, a length of 70 cm and a height of 10 cm. At this time, the bat was filled with the resin-coated carbon black.
And it dried at 70 degreeC with a vacuum dryer for 7 hours, and removed water and toluene. However, carbon black E in Table 1 was dried at 150 ° C. for 2 hours. The average amount of residual toluene in the obtained resin-coated carbon black was 50 pp.
m, and the average residual water amount was 500 ppm. The measurement results of the gel fraction of the epoxy resin coating layer were as shown in Table 1.

[0022]

[Table 1]

(2) Synthesis of binder resin: 32 g of trimer of tolylene diisocyanate (“Mitec GP750A” manufactured by Mitsubishi Chemical Corporation, resin solid content: 50% by weight, butyl acetate solution) and dibutyltin dilaurate as a catalyst 0.02 g was dissolved in 47 g of propylene glycol monomethyl ether acetate (PGMEA). Then
Under stirring conditions, polyethylene glycol having a methoxy group at one end (“UNIOX M” manufactured by NOF CORPORATION)
A mixture of 14.4 g of “-1000”: molecular weight of 1,000) and 9.6 g of polypropylene glycol (“Sannicks PP-1000”, manufactured by Sanyo Chemical Industries, Ltd .: molecular weight of 1,000) was dropped at 70 ° C. The reaction was further performed for 3 hours. The reaction was then added to N, N-dimethylamino-
After 1 g of 1,3-propanediamine was added, the mixture was further reacted at 40 ° C. for 1 hour. The amine value of the obtained dispersion resin-containing solution was determined by neutralization titration, and as a result, 14 mgKOH /
g. Further, as a result of obtaining a resin content by a dry-up method of removing a solvent by a hot plate at 150 ° C. for 30 minutes and calculating a resin concentration by a weight change amount,
It was 40% by weight.

(3) Synthesis of polymer dispersant: styrene / acrylic acid resin (acid value 200, molecular weight 5,000) 20
g, p-methoxyphenol 0.2 g, dodecyltrimethylammonium chloride 0.2 g, PGMEA 40 g
Was charged into a flask, 7.6 g of (3,4-epoxycyclohexyl) methyl acrylate was added dropwise, and the mixture was reacted at a temperature of 100 ° C. for 30 hours. Next, the reaction solution was reprecipitated with water, and the recovered resin was dried. The acid value of the obtained resin determined by neutralization titration with KOH was 80.

Examples 1 to 3 and Comparative Examples 1 and 2 50 parts by weight of the various resin-coated carbon blacks obtained in the above (1) and the binder resin 5 obtained in the above (2)
Parts by weight (as a solid content) and a solid content concentration of 50
A dispersion was prepared by adding PGMEA so as to obtain a weight%. Next, 50 g of the obtained dispersion liquid was subjected to a preliminary stirring treatment, and then subjected to a dispersion treatment at 25 to 45 ° C for 6 hours by a paint shaker. This dispersion treatment has a diameter of 0.5 m.
m of zirconia beads were used in the same weight ratio as the dispersion. After the dispersion treatment, the dispersion liquid and the beads were separated by a filter.

Next, the above resin-coated carbon black dispersion ink was used and mixed with the components shown in Table 2 to obtain a photopolymerizable composition for a black matrix (coating solution).
Was prepared and subjected to evaluation of dispersibility and measurement of surface resistance described below. Table 4 shows the results. In addition, the g number in Table 2 is a value as a solid content.

[0027]

(A) 50 g of resin-coated carbon black (b) polymerization initiation system (1) 2,2 ′-(o-chlorophenyl) -4,5,4 ′, 5′-tetraphenyl-1,2′- Biimidazole 2 g (2) Butanediol bisthiopropionate 1 g (3) 4,4'-bis- (diethylamino) benzophenone 1 g (4) 2-mercaptobenzothiazole 1 g (c) Binder resin (see (2) above) 25 g (d) Dipentaerythritol hexaacrylate 15 g (e) Propylene glycol monomethyl ether acetate (solvent) 300 g (f) Polymer dispersant (see (3) above) 5 g

(1) Evaluation of dispersibility: The above-mentioned photopolymerizable composition for black matrix (coating solution) was applied on a glass substrate to a thickness of about 0.5 mm, and then dried to form a coating film. After embedding the coating film with epoxy resin, cut out a slice of about 800 mm thick with an ultra microtome,
Observation was performed using an electron microscope at a magnification of 5000, and the evaluation was performed based on the following three criteria.

[0029]

[Table 3] ・ ・ ・: Aggregates of almost less than 0.1 μm ○: Aggregates of 0.1 to 1 μm △: Aggregates of almost more than 1 μm

(2) Surface resistance measurement: The dried coating film obtained in the above evaluation of dispersibility was used as a measurement sample, and a surface resistance measurement device (manufactured by Co., Ltd.)
"Histar MCP-HT2" manufactured by Dia Instruments
01 ") was used to measure the surface resistance.

[0031]

[Table 4]

[0032]

According to the present invention described above, for example,
Suitable for use in black resist pattern formation applications, etc.
The present invention provides a resin-coated carbon black which is excellent in dispersibility in preparing a photopolymerizable composition for forming a black resist pattern and, as a result, can provide a photopolymerizable composition having excellent development characteristics, and a method for producing the same.

────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] December 19, 1997

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0023

[Correction method] Change

[Correction contents]

(2) Synthesis of polymer dispersant: 32 g of a trimer of tolylene diisocyanate (“Mitec GP750A” manufactured by Mitsubishi Chemical Corporation: resin solid content of 50% by weight, butyl acetate solution) and dibutyl as a catalyst 0.02 g of tindyl laurate was dissolved in 47 g of propylene glycol monomethyl ether acetate (PGMEA). Then
Under stirring conditions, polyethylene glycol having a methoxy group at one end (“UNIOX M” manufactured by NOF CORPORATION) was added to this solution under stirring conditions.
A mixture of 14.4 g of “-1000”: molecular weight of 1,000) and 9.6 g of polypropylene glycol (“Sannicks PP-1000”, manufactured by Sanyo Chemical Industries, Ltd .: molecular weight of 1,000) was dropped at 70 ° C. The reaction was further performed for 3 hours. The reaction was then added to N, N-dimethylamino-
After 1 g of 1,3-propanediamine was added, the mixture was further reacted at 40 ° C. for 1 hour. The amine value of the obtained dispersion resin-containing solution was determined by neutralization titration, and as a result, 14 mgKOH /
g. Further, as a result of obtaining a resin content by a dry-up method of removing a solvent by a hot plate at 150 ° C. for 30 minutes and calculating a resin concentration by a weight change amount,
It was 40% by weight.

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0024

[Correction method] Change

[Correction contents]

(3) Synthesis of binder resin: styrene
Acrylic resin (acid value 200, molecular weight 5,000) 20
g, p-methoxyphenol 0.2 g, dodecyltrimethylammonium chloride 0.2 g, PGMEA 40 g
Was charged into a flask, 7.6 g of (3,4-epoxycyclohexyl) methyl acrylate was added dropwise, and the mixture was reacted at a temperature of 100 ° C. for 30 hours. Next, the reaction solution was reprecipitated with water, and the recovered resin was dried. The acid value of the obtained resin determined by neutralization titration with KOH was 80.

Claims (1)

[Claims] 1. A resin-coated carbon black coated with a polyfunctional epoxy resin and having a gel fraction of 20 to 70% of the polyfunctional epoxy resin in a coating layer.