JP2008127448A - Black material, dispersion of black fine particle, black light-shielding film, and base material with black light-shielding film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a black material having high blackness and excellent light-shielding properties, to provide a dispersion of black fine particles, capable of being easily dispersed even in a nonaqueous light-sensitive resin by using the black material, to provide a black light-shielding film, and to provide a base material with the black light-shielding film attached thereto. <P>SOLUTION: The black material comprises particles containing one or more kinds selected from the group consisting of silver, tin, and a silver-tin alloy. When the particle contains the silver and/or the silver-tin alloy, the content of the silver in the particle is ≥30 wt.% and ≤90 wt.%. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a black material, a black fine particle dispersion, a black light-shielding film, and a substrate with a black light-shielding film, and is particularly suitable for a recording material, a black matrix of various display devices, and the like. An excellent black material, a black fine particle dispersion that can be easily dispersed even with a non-aqueous photosensitive resin by using this black material, a black light shielding film and a black light shielding film obtained by applying this black fine particle dispersion It is related with a base material with attachment.

Conventionally, carbon black, low-order titanium oxide, iron oxide, chromium, silver fine particles, and the like are known as black materials (see, for example, Patent Document 1).
These black materials are black light shielding film, black light shielding glass, black paper, black cloth, black ink, black matrix material for plasma display (PDP) and liquid crystal display (LCD), black seal material, black mask material. For example, it is used as a material for imparting black color or light-shielding property to the like.
When these black materials are used for a black matrix such as a liquid crystal display, a coating solution in which a black material, a photosensitive resin, a photoinitiator, and the like are mixed is applied to a substrate, and a desired pattern is formed through an exposure / development process. The technique of forming is taken.

By the way, these carbon black, low-order titanium oxide, iron oxide and the like have a defect that the light shielding property is insufficient, and chromium has a defect that the environmental load is large because it is a heavy metal, and silver fine particles. Is a noble metal and therefore has a disadvantage of being expensive. Therefore, as a black material capable of eliminating these disadvantages, a black material mainly composed of silver-tin alloy particles having an average particle diameter of 1 nm or more and 300 nm or less has been proposed. (Patent Document 2).
JP-A-5-127433 JP 2006-89771 A

By the way, the conventional black material mainly composed of silver tin alloy particles is used in the state of an aqueous dispersion, so that it is generally used monofunctional (meth) acrylate, polyfunctional (meth) acrylate, urethane acrylate. There is a problem that it cannot be dispersed in photosensitive resins such as polyesters and polyester acrylates.
In this case, there is a method of using a water-based photosensitive resin to facilitate the dispersion of the black material, but since the types of water-based photosensitive resins are limited, a coating film or pattern having a desired function is used. There was a problem that the conditions for obtaining the above were restricted.

  The present invention has been made in order to solve the above-described problems, and is a black material having high blackness and excellent light-shielding properties, and even if it is a non-aqueous photosensitive resin by using this black material. It is an object of the present invention to provide a black fine particle dispersion, a black light-shielding film, and a substrate with a black light-shielding film that can be dispersed in a thin film.

  As a result of intensive studies on a black material having high blackness, excellent light-shielding properties, and capable of being easily dispersed even with a non-aqueous photosensitive resin, the present inventors have determined that the black material is silver, tin, silver tin It has been found that a black material having high blackness and excellent light-shielding properties can be obtained by constituting with particles containing one or more selected from the group of alloys. It has been found that if a non-aqueous dispersion liquid is dispersed in a dispersion medium containing an aqueous solvent as a main component, even a non-aqueous photosensitive resin can be easily dispersed, and the present invention has been completed. It was.

That is, the black material of the present invention is characterized by comprising particles containing one or more selected from the group of silver, tin and silver-tin alloys.
When the particles contain silver and / or a silver tin alloy, the silver content of the particles is preferably 30% by weight or more and 90% by weight or less.

The black fine particle dispersion of the present invention is characterized in that the black material of the present invention is dispersed in a dispersion medium containing a non-aqueous solvent as a main component.
This dispersion preferably has a water content of 5% by weight or less.

The black light-shielding film of the present invention is formed by applying a coating liquid containing the black fine particle dispersion of the present invention and a non-aqueous photosensitive resin.
The base material with a black light-shielding film of the present invention is characterized in that the black light-shielding film of the present invention is provided on one main surface of the base material.

  According to the black material of the present invention, the black material is made of particles containing one or more selected from the group of silver, tin, and silver-tin alloy, so that the blackness of the black material itself can be improved. And the light shielding property can be improved.

According to the black fine particle dispersion of the present invention, since the black material of the present invention is dispersed in a dispersion medium containing a non-aqueous solvent as a main component, the black fine particle dispersion is mixed with a non-aqueous photosensitive resin. Thus, the black material can be easily dispersed in the non-aqueous photosensitive resin.
Therefore, from various types of photosensitive resins, those suitable for the desired exposure, development conditions, film properties, etc. can be selected as appropriate, and there are no restrictions on the dispersion or coating film, and the degree of freedom in designing these products. Can be spread.

The best mode of the black material of the present invention, the black fine particle dispersion, the black light shielding film, and the substrate with the black light shielding film will be described.
This embodiment is specifically described for better understanding of the gist of the invention, and does not limit the present invention unless otherwise specified.

"Black material"
The black material of the present invention comprises particles containing one or more selected from the group consisting of silver, tin and silver-tin alloys.
When the particles contain silver and / or silver tin alloy, the silver content of the particles is preferably 30% by weight or more and 90% by weight or less, more preferably 40% by weight or more and 85% by weight or less, More preferably, they are 50 weight% or more and 80 weight% or less.

  Here, the reason why the silver content of the particles is limited to 30% by weight or more and 90% by weight or less is that if the content is less than 30% by weight, the composition is relatively rich in tin, and the tin itself is thermal. This is because it is poor in stability and easily oxidizes, so that there is a risk of deterioration of the light-shielding property due to aging or heat treatment, discoloration, etc. On the other hand, if the silver content exceeds 90% by weight, the composition of excessive silver Thus, when the film is formed, there is a possibility that the film has a metal color and high reflectivity although it is excellent in light shielding properties.

This black material can be produced using a normal fine particle synthesis method. As the fine particle synthesis method, any method such as a gas phase reaction method, a spray pyrolysis method, an atomization method, a liquid phase reaction method, a freeze-drying method, or a hydrothermal synthesis method may be used.
According to this black material, since it is composed of particles containing one or more selected from the group of silver, tin, and silver-tin alloy, the blackness of the black material itself can be increased, and light shielding Can also be improved.

"Black fine particle dispersion"
The black fine particle dispersion of the present invention is a dispersion obtained by dispersing the black material in a dispersion medium containing a non-aqueous solvent as a main component.
The dispersion medium containing the non-aqueous solvent as a main component refers to a dispersion medium in which the weight percentage of the non-aqueous solvent in the dispersion medium is 95% by weight or more.

  Examples of the non-aqueous solvent include alcohols such as 1-propanol, 2-propanol, butanol and octanol, ethyl acetate, butyl acetate, ethyl lactate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, and γ-butyrolactone. Esters such as diethyl ether, ethylene glycol monomethyl ether (methyl cellosolve), ethylene glycol monoethyl ether (ethyl cellosolve), ethylene glycol monobutyl ether (butyl cellosolve), ethers such as diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, acetone, Methyl ethyl ketone, methyl isobutyl ketone, acetylacetone, cyclohexanone, 4-hydro Ketones such as cis-4-methyl-2-pentanone (diacetone alcohol), aromatic hydrocarbons such as benzene, toluene, xylene and ethylbenzene, amides such as dimethylformamide, N, N-dimethylacetamide and N-methylpyrrolidone Are preferably used, and one or more of these solvents can be used.

The water content of this dispersion is preferably 5% by weight or less, more preferably 3% by weight or less, and still more preferably 2% by weight or less.
Here, the reason for setting the water content of the dispersion to 5% by weight or less is that when the water content exceeds 5% by weight, the dispersion is monofunctional (meth) acrylate, polyfunctional (meth) acrylate, urethane acrylate, This is because, when mixed with a non-aqueous photosensitive resin such as polyester acrylate, the dispersion and the non-aqueous photosensitive resin are easily separated, and it is difficult to obtain a stable mixture.

  By setting the water content of this dispersion to 5% by weight or less, it is possible to appropriately select a resin that suits desired exposure, development conditions, film properties, etc. from many types of non-aqueous photosensitive resins, There are no restrictions on the dispersion or coating film, and the degree of freedom in these designs can be expanded.

"Black shading film"
The black light-shielding film of the present invention is a coating liquid obtained by mixing the black fine particle dispersion of the present invention and a non-aqueous photosensitive resin, and dispersing the black fine particle dispersion in the non-aqueous photosensitive resin. The liquid is obtained by applying a coating method such as a roll coating method, a spin coating method, or a dip coating method.
Moreover, the base material with a black light shielding film of this invention is obtained by apply | coating this coating liquid to one main surface of a base material.

  Here, as a non-aqueous photosensitive resin, for example, monofunctional (meth) acrylate, polyfunctional (meth) acrylate, urethane acrylate, polyester acrylate, polymethyl methacrylate (PMMA), acrylate such as polycyclohexyl methacrylate, polycarbonate (PC ), Polystyrene (PS), polyether, polyester, polyarylate, polyacrylic acid ester, polyamide, phenol-formaldehyde (phenol resin), diethylene glycol bisallyl carbonate, acrylonitrile / styrene copolymer (AS resin), methyl methacrylate / Styrene copolymer (MS resin), poly-4-methylpentene, norbornene-based polymer, polyurethane, epoxy, silicone and the like can be mentioned, particularly preferably It is an acrylate.

According to the black light-shielding film of the present invention, the black fine particle dispersion of the present invention and a non-aqueous photosensitive resin are mixed to form a coating liquid in which the black fine particle dispersion is dispersed in the non-aqueous photosensitive resin. Since it is obtained by applying this coating solution, the blackness is high and the light shielding property is excellent.
Since this black light-shielding film can be produced by a coating method, a black light-shielding film having a desired pattern and film properties can be easily and inexpensively formed when applied to a black matrix such as a liquid crystal display. .

  EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention concretely, this invention is not limited by these Examples.

(Example 1)
(Preparation of silver tin fine particle dispersion)
10 g of a tin colloid (average particle size: 30 nm, solid content: 10% by weight, manufactured by Sumitomo Osaka Cement Co., Ltd.) was collected, and pure water was added thereto to prepare a tin colloid solution having a total volume of 300 ml.
Pure water was added to 23 g of glucose, 2.0 g of tartaric acid, and 40 g of ethanol to prepare a glucose mixed solution having a total weight of 500 g.
Further, 50 ml of concentrated ammonia water (NH ₃ : 28%) was added to 15 g of silver nitrate, and pure water was further added to prepare a silver nitrate solution having a total weight of 500 g.

Next, the glucose mixed solution and the silver nitrate solution are mixed, 100 g is taken from the obtained mixed solution, added to the tin colloid solution, and 0.05 N aqueous sodium hydroxide solution is added to this solution while stirring the obtained solution. 10 g was slowly added dropwise.
Next, this solution was stirred for 10 minutes using a magnetic stirrer, and then washed by centrifugation. An aqueous dispersion containing silver tin fine particles (solid content: 10% by weight, silver content in the solid content) : 62.5% by weight).

Subsequently, 300 g was fractionated from the aqueous dispersion containing the silver tin fine particles to prepare a liquid A.
Further, 3 g of a basic comb polymer as a dispersant was dissolved in 27 g of acetone to obtain a liquid B.
Subsequently, after adding this B liquid to A liquid and mixing, a water | moisture content and acetone were evaporated using this evaporator from this mixture, dry powder was obtained, and it was set as C powder.
Next, 11 g of C powder, 44.5 g of methyl ethyl ketone (MEK), 44.5 g of propylene glycol monomethyl ether acetate (PGMEA) were mixed, and then dispersed using a sand grinder to obtain a non-aqueous silver tin fine particle dispersion. .

(Evaluation of dispersion)
This non-aqueous silver tin fine particle dispersion was diluted with methyl ethyl ketone (MEK) so that the solid content contained in the dispersion was 0.005% by weight, and the absorbance at a wavelength of 500 nm was measured.
Here, if this absorbance can be compared with a value obtained by diluting an aqueous dispersion with water so that its solid content is 0.005 wt%, the absorbance of the aqueous dispersion and the non-aqueous dispersion It is preferable because the difference between the two can be confirmed.

In this measurement, the weight percentage of the black material is the same when diluted with water and when diluted with methyl ethyl ketone (MEK), but the specific gravity of water and methyl ethyl ketone (MEK) is different, so the black material per volume The amounts are different and the absorbance cannot be compared. Therefore, the absorbance obtained by dilution with methyl ethyl ketone (MEK) was converted so that the amount of the black material per volume was the same as when diluted with water.
The water content of the dispersion was measured using a Karl Fischer moisture measuring device (AQ-2000: manufactured by Hiranuma Sangyo Co., Ltd.).

(Preparation of coating solution)
29 g of PGMEA, 29 g of MEK, 40 g of the above-mentioned silver tin fine particle dispersion, 2 g of dipentaerythritol hexaacrylate (photosensitive resin), and a leveling agent were mixed to obtain a coating solution. The dispersibility of the coating solution in the photosensitive resin was evaluated by visual observation, and “◯” was determined to be recognized as having no precipitate and maintaining a good dispersion state.
(Black film formation)
Next, this coating solution was applied to a glass substrate by a spin coating method to form a black coating film. The film-forming property of this black coating film was evaluated by visual observation, and no film-forming defects such as irregularities and holes were observed on the surface of the film, and a film that could be formed into a coating film was rated as “◯”.

(Example 2)
C powder was produced in the same manner as in Example 1.
Next, 11 g of C powder and 89 g of methyl ethyl ketone (MEK) were mixed and then dispersed using a sand grinder to obtain a non-aqueous silver tin fine particle dispersion.
Next, according to Example 1, the absorbance and water content of the dispersion, the dispersibility in the photosensitive resin, and the film formability of the black coating film were evaluated.

(Example 3)
In Example 1, a non-aqueous silver-tin fine particle dispersion was used in the same manner as in Example 1 except that the silver-solid fine particle-containing aqueous dispersion used was a solid content of 50% by weight of silver. Got.
Next, according to Example 1, the absorbance and water content of the dispersion, the dispersibility in the photosensitive resin, and the film formability of the black coating film were evaluated.

Example 4
In Example 1, a non-aqueous silver-tin fine particle dispersion was used in the same manner as in Example 1 except that a silver-solid fine particle-containing aqueous dispersion having a solid content of 80% by weight was used. Got.
Next, according to Example 1, the absorbance and water content of the dispersion, the dispersibility in the photosensitive resin, and the film formability of the black coating film were evaluated.

(Example 5)
A liquid A was produced in the same manner as in Example 1.
Subsequently, this A liquid and 350 g of diacetone alcohol were mixed, and the water | moisture content was evaporated using this evaporator from the mixture, and the non-aqueous silver tin fine particle diacetone alcohol dispersion liquid was obtained.
Next, according to Example 1, the absorbance and water content of the dispersion, the dispersibility in the photosensitive resin, and the film formability of the black coating film were evaluated.

(Example 6)
In Example 5, non-aqueous silver tin fine particle diacetone was used in the same manner as in Example 5 except that the aqueous dispersion containing silver tin fine particles had a silver content of 50% by weight. An alcohol dispersion was obtained.
Next, according to Example 1, the absorbance and water content of the dispersion, the dispersibility in the photosensitive resin, and the film formability of the black coating film were evaluated.

(Example 7)
In Example 5, a non-aqueous silver tin fine particle diacetone was used in the same manner as in Example 5, except that the aqueous dispersion containing silver tin fine particles used had a silver content of 80% by weight in the solid content. An alcohol dispersion was obtained.
Next, according to Example 1, the absorbance and water content of the dispersion, the dispersibility in the photosensitive resin, and the film formability of the black coating film were evaluated.

(Comparative Example 1)
The aqueous dispersion (solid content: 10% by weight, silver content in the solid content: 62.5% by weight) used in Example 1 was photosensitive in the same manner as in Example 1. Dispersion into the resin was performed.
The absorbance was measured by diluting the aqueous dispersion to 0.005% by weight with water and measuring the absorbance at a wavelength of 500 nm.
The water content was determined by measuring the weight of the solid content remaining after drying the aqueous dispersion at 150 ° C. for 60 minutes, and calculating the difference between the measured value and the weight of the aqueous dispersion before drying. The water content was calculated as an amount.

(Comparative Example 2)
A photosensitive resin was prepared in the same manner as in Comparative Example 1 except that the aqueous dispersion containing silver tin fine particles used in Example 1 had a silver content of 50% by weight in the solid content. Dispersion, absorbance, and water content were calculated.

(Comparative Example 3)
A photosensitive resin was prepared in the same manner as in Comparative Example 1, except that the aqueous dispersion containing silver tin fine particles used in Example 1 had a silver content of 80% by weight in the solid content. Dispersion, absorbance, and water content were calculated.
These measurement results are shown in Table 1.

According to this table, in Examples 1 to 7, it was stably dispersed in the photosensitive resin, and the film formability of the black coating film was satisfactory.
On the other hand, in Comparative Examples 1-3, it was not able to disperse | distribute to photosensitive resin and a black coating film could not be formed.
In Examples 1 to 7 and Comparative Examples 1 to 3, the absorbance of the dispersions showed an equivalent value.

  The black material of the present invention has a high blackness and excellent light-shielding properties, and by using this black material, a black fine particle dispersion that can be easily dispersed even with a non-aqueous photosensitive resin is obtained. Because it is obtained, it can be applied to any material that requires blackness and light-shielding properties by appropriately selecting one that meets the desired exposure, development conditions, film properties, etc. Is possible. For example, black light shielding film, black light shielding glass, black paper, black cloth, black ink, black matrix material for display devices such as plasma display (PDP) and liquid crystal display (LCD), black seal material, black mask It can also be used as a material.

Claims (6)

  A black material comprising particles containing one or more selected from the group consisting of silver, tin and silver-tin alloys.   2. The black material according to claim 1, wherein when the particles contain silver and / or a silver tin alloy, the silver content of the particles is 30 wt% or more and 90 wt% or less.   A black fine particle dispersion, wherein the black material according to claim 1 or 2 is dispersed in a dispersion medium containing a non-aqueous solvent as a main component.   The black fine particle dispersion according to claim 3, wherein the water content is 5% by weight or less.   A black light-shielding film obtained by applying a coating liquid containing the black fine particle dispersion of claim 3 or 4 and a non-aqueous photosensitive resin.   A base material with a black light-shielding film, comprising the black light-shielding film according to claim 5 on one main surface of the base material.