JP2007177200A - Printing ink composition and method for producing color filter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a printing ink composition capable of improving the formation of a highly fine pattern, pattern accuracy and form, which become problems of a printing method and also the stability of a very fine pigment; and also to provide a method for producing a color filter capable of stabilizing the very fine pigment so as to improve the formation of the highly fine pattern and its form. <P>SOLUTION: This printing ink composition containing the pigment, a filler, a resin component and a solvent, and used in an inversion offset method is characterized by having 20-55 wt.% content of the pigment based on its solid portion, 50 to <500 nm position of peak top of a peak showing the maximum value in the particle diameter distribution of the pigment, 5-40 wt.% content of the filler based on its solid portion, and also 10 to <100 nm position of peak top of a peak showing the maximum value in the particle diameter distribution of the filler. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a printing ink composition for forming a colored image and a method for producing a color filter using the printing ink composition.

In recent years, color filters are frequently used in liquid crystal display devices, sensors, color separation devices, and the like. As a manufacturing method of this color filter, conventionally, a dyeable resin, for example, natural gelatin or casein is patterned and dyed mainly using a dye to obtain pixels.
However, the pixel obtained by this method has a problem that heat resistance and light resistance are low due to restrictions on materials.

  Therefore, in recent years, a method (pigment dispersion method) using a photosensitive material in which a pigment is dispersed for the purpose of improving heat resistance and light resistance has attracted attention and many studies have been conducted. According to this method, the manufacturing method is simplified, and the obtained color filter is known to be stable and have a long lifetime.

  However, with the recent increase in size of substrates, color filters produced by the pigment dispersion method require large exposure machines, developing devices, baking furnaces, and clean rooms in which these are installed, and capital investment has become enormous. .

  Also, it is difficult to apply a substrate of 1 m square or more with a spin coater. Therefore, a coating device such as a slit coater is used, but there is a problem that it is difficult to ensure the uniformity of the coating film. In particular, the first color, the second color, the third color when using a resin black matrix, and the second color and the third color when using a thin metal black matrix apply a resist to the substrate surface with a difference in level. Is difficult to secure.

  On the other hand, there is a strong demand for cost reduction of color filters, and there is a demand for a method for producing color filters other than the photolithography method using expensive equipment such as the above-described exposure machine. Electrodeposition methods and printing methods have been conventionally proposed as methods for producing color filters other than the photolithographic method.

  Among these, the printing method is attracting attention as an inexpensive manufacturing method, but it has been difficult to manufacture a color filter having good surface smoothness and high-definition pattern dimensions and shape by the conventional printing method. It was.

As described in Patent Document 1, an ink composition used for a conventional color filter is usually a high-viscosity paste product of 20 to 100 Pa · s. Therefore, the conventional printing ink composition has insufficient flatness of the coating film surface, and it has been difficult to obtain a high-definition pattern or a uniform coating film surface.
Moreover, the fine stabilization of the pigment required for increasing the transmittance of the color filter was insufficient.

  Furthermore, a novel offset printing method as described in Patent Documents 2 and 3 has been proposed, but the composition for printing ink used in such a printing method usually uses a high-viscosity colored paste. Therefore, it is inadequate to obtain a high-definition pattern and a uniform coating surface, and the pigment is not sufficiently stabilized, and inconveniences such as pigment aggregation occur when a diluent is used. was there.

JP-A-5-320553 JP-A-11-58921 Japanese Patent Laid-Open No. 11-97032

  In view of the above problems, an object of the present invention is to provide a printing ink composition capable of improving the formation of a high-definition pattern, pattern accuracy and shape, which are problems in the printing method, and further enabling fine stabilization of the pigment. It is to provide. Furthermore, the present invention provides a method for producing a color filter using the printing ink composition, which can finely stabilize pigments and improve the formation and shape of high-definition patterns.

  As a result of various studies on the above-mentioned problems, the present inventors have controlled the content of pigments and fillers and the particle size distribution of the pigments and fillers, thereby improving the printing accuracy and pattern accuracy. As a result, it was found that a color filter can be produced at low cost, and the present invention has been completed.

That is, the present invention
(1) In the printing ink composition used for the reverse offset method containing a pigment, a filler, a resin component, and a solvent, the pigment content is 20 to 55% by weight in terms of solid content, and the maximum in the particle size distribution of the pigment The peak top position of the peak showing the value is 50 nm to less than 500 nm, the filler content is 5 to 40% by weight in terms of solid content, and the peak showing the maximum value in the particle size distribution of the filler The printing ink composition characterized in that the peak top position is less than 10 to 100 nm (2) In the above (1), the total content of the pigment and the filler is 40 to 70% by weight in terms of solid content The printing ink composition,
(3) The above (1) or (1), wherein the solvent contains propylene glycol monomethyl ether acetate and additionally contains at least one selected from the group consisting of hydrocarbon solvents, ester solvents, alcohol solvents, and ketone solvents. 2) the printing ink composition according to
(4) The printing ink composition according to any one of (1) to (3), wherein the filler is a metal oxide, a metal nitride, or a mixture thereof.
(5) From the group consisting of an acrylic resin, an epoxy resin, a melamine resin, a polyester resin, a urethane resin, an alkyd resin, a monomer having two or more photopolymerizable unsaturated bonds in the molecule, and a polymer of the monomer. The printing ink composition according to any one of the above (1) to (4), which is at least one selected;
(6) The printing ink composition according to any one of (1) to (5), wherein the viscosity is 50 mPa · s or less,
(7) The printing ink composition according to any one of (1) to (6) above for use in a color filter, and (8) the printing ink composition according to any one of (1) to (7) above. An application step of forming an application surface by applying to the silicon resin surface, a removal step of transferring and removing the printing ink composition on the convex portion of the relief plate by pressing the relief plate formed in a predetermined shape against the application surface, A method for producing a color filter comprising a transfer step of transferring the printing ink composition remaining on the coated surface to a substrate,
Is to provide.

The printing ink composition of the present invention can improve the formation of a high-definition pattern, pattern accuracy and shape, which are problems in the printing method, and can finely stabilize the pigment.
In addition, the color filter produced by the method of the present invention can finely stabilize the pigment, and can improve the formation and shape of a high-definition pattern.

The printing ink composition of the present invention includes a pigment, a filler, a resin component, and a solvent.
As the pigment used in the printing ink composition of the present invention, organic pigments and inorganic pigments used in the pigment dispersion method for color filters can be used. In the present invention, organic pigments are preferred, and specific examples include azo, phthalocyanine, indigo, anthraquinone, perylene, quinacridone, methine / azomethine, and isoindolinone.

  The pigment is contained in the printing ink composition in an amount of 20 to 55% by weight in terms of solid content. If the pigment content is less than 20% by weight, the formation of a high-definition pattern, which is a problem in the printing method, and the pattern accuracy and shape are poor. On the other hand, if the content exceeds 55% by weight, the pattern is cracked or the adhesion to the substrate is significantly reduced. From the above points, the pigment content is preferably in the range of 30 to 55% by weight, and more preferably in the range of 40 to 55% by weight. These pigments can be used alone or in combination of two or more. In the present invention, as will be described in detail later, since the printability is improved by including a filler as an essential component in the printing ink composition, the content of the pigment as compared with the case where no filler is included. Can be made relatively small.

Moreover, it is essential that the peak top position of the peak showing the maximum value is in a range of 50 nm to less than 500 nm in the particle size distribution of the pigment. When the particle size is less than 50 nm, in the process of producing a color filter, silicon is violated when a pigment adheres to the silicon resin surface or the silicon blanket, which is not suitable for mass production. On the other hand, when the particle size is 500 nm or more, defects occur in the formation of a high-definition pattern, pattern accuracy, and shape, which are problems in the printing method. From the above points, the particle size is preferably in the range of 60 nm to 350 nm, and more preferably in the range of 70 nm to 200 nm. In the present invention, as will be described in detail later, the printability is improved by including a filler as an essential component in the printing ink composition, so that the particle size is larger than when no filler is included. Pigments can be used.
In general, when one kind of pigment is used, the particle size distribution has one peak, and the peak top position of the peak is within the above range. When a mixture of pigments is used, a plurality of peaks may appear. In this case, the peak top position of the peak showing the maximum value is within the above range.

Furthermore, in the particle size distribution of the pigment, the pigment having a particle size of 200 nm or more is preferably 33% by weight or less. When the pigment having a particle diameter of 200 nm or more is 33% by weight or less, the formation of a high-definition pattern, the pattern accuracy, and the shape that are problems in the printing method are improved.
Among the color filter patterns, particularly, the black matrix is required to have a high-definition pattern having a width of 20 μm or less, and the pigment used in such a high-definition pattern is a pigment having a particle size of 200 nm or more, 33 wt% or less, and further 15 wt% or less. In particular, it is preferable that a pigment having a particle size of 200 nm or more is below the lower limit of detection, that is, not present.

Here, the particle diameter of the pigment is measured by a photon correlation method (PCS) based on a dynamic light scattering method by Brownian motion of a pigment dispersed in a solvent. As a measuring device, N5 manufactured by Beckman Coulter can be used. The particle size distribution (in terms of weight) can be determined from the scattering intensity distribution by spherical Mie scattering approximation by software or the like attached to the measuring apparatus.
The high-definition pattern refers to a pattern width region of a color filter that is generally required to be used for next-generation LCDs with a width of 80 μm or less, and the pattern accuracy refers to, for example, variation in pattern width, ± 1 to If it exceeds 2%, it may be considered defective.

When the printing ink composition of the present invention is applied to a color filter, each pigment system suitable for colored images such as red, green, blue and black is used.
As a red colored image, a single red pigment system may be used, or a yellow pigment system may be mixed with a red pigment system to perform toning.
Examples of the red pigment system include a color index name, C.I. I. Pigment red 9, 123, 155, 168, 177, 180, 217, 220, 224, 254 and the like.
Examples of the yellow pigment system include a color index name, C.I. I. Pigment yellow 17, 20, 24, 83, 93, 109, 110, 117, 125, 128, 129, 138, 139, 147, 150, 154, 180, 185 and the like.
These red pigment systems and yellow pigment systems can be used in combination of two or more. When using a mixture of a red pigment system and a yellow pigment system, the yellow pigment system is preferably used in an amount of 60 parts by weight or less with respect to 100 parts by weight of the total amount of the red pigment system and the yellow pigment system. .

As the green colored image, a single green pigment system may be used, and the above yellow pigment system may be mixed with a green pigment system to perform toning.
Examples of the green pigment system include color index names such as C.I. I. Pigment green 7, 36, 37, and the like.
Two or more of these green pigment systems and yellow pigment systems can be mixed and used. In the case of using a mixture of a green pigment system and a yellow pigment system, the yellow pigment system is preferably used in an amount of 50 parts by weight or less with respect to 100 parts by weight of the total amount of the green pigment system and the yellow pigment system.

As a blue colored image, a single blue pigment system may be used, or a purple pigment system may be mixed with a blue pigment system to perform toning.
Examples of the blue pigment system include a color index name, C.I. I. Pigment blue 15, 15: 3, 15: 4, 15: 6, 22, 60, and the like.
Examples of purple pigments include the color index name, C.I. I. Pigment violet 19, 23, 29, 37, 50 and the like.
Two or more of these blue pigment systems and purple pigment systems can be used in combination. In the case of using a mixture of a blue pigment system and a violet pigment system, the violet pigment system is preferably used in an amount of 50 parts by weight or less with respect to 100 parts by weight of the total amount of the blue pigment system and the violet pigment system.
As the black colored image, for example, black pigments such as carbon black, graphite, titanium carbon, black iron, black nickel, titanium black, and manganese dioxide are used.

Next, the filler used in the printing ink composition of the present invention is not particularly limited, but metal oxides such as silicon oxide, aluminum oxide, titanium oxide, and zinc oxide, and metal nitrides such as silicon nitride and aluminum nitride. Products and mixtures thereof can be used. Since it is inexpensive and has a refractive index close to that of an organic resin, a commercially available product is preferably used as a slurry of silicon oxide prepared from colloidal silica or a liquid phase. In addition, a silica slurry or powder produced by a vapor phase method or a pulverization method may be used.
The filler is contained in the printing ink composition in an amount of 5 to 40% by weight in terms of solid content, preferably 5 to 30% by weight, more preferably 5 to 20% by weight.

  Moreover, it is essential for the filler that the position of the peak top of the peak showing the maximum value is in the range of 10 nm to less than 100 nm in the particle size distribution. When the particle size is less than 10 nm, in the process of producing a color filter, silicon is committed when the filler adheres to the silicon resin surface or the silicon blanket, which is not suitable for mass production. On the other hand, when the particle size is 100 nm or more, the formation of a high-definition pattern, the pattern accuracy and the shape, which are problems in the printing method, are deteriorated, and the optical performance such as transmittance and contrast of the color filter is deteriorated. From the above points, the particle size is preferably in the range of 20 nm to less than 80 nm, and more preferably in the range of 30 nm to less than 70 nm.

  In the printing ink composition of the present invention, the total content of the pigment and the filler is preferably 40 to 70% by weight in terms of solid content. When the content is 40% by weight or more, there is no defect in formation of a high-definition pattern, pattern accuracy, and shape, which are problems in the printing method. On the other hand, when the content is 70% by weight or less, the pattern does not crack, and the adhesion to the substrate is improved. In view of the above, the content is preferably in the range of 50 to 70% by weight.

  Next, as the resin component used in the printing ink composition of the present invention, when the printing ink composition is used, those having pigment dispersibility are preferred, and those having film formability and transparency are preferred. Examples of such resin components include acrylic resins, epoxy resins, melamine resins, polyester resins, urethane resins, alkyd resins, and the like, and monomers having two or more photopolymerizable unsaturated bonds in the molecule and the weight of the monomers. Examples include coalescence (including oligomers).

Among the above resin components, acrylic resin is preferred from the viewpoint of film formation and pigment dispersibility on the silicon resin surface or silicon blanket in the process of manufacturing a color filter, and acrylic resin used for photolithography resists is preferably pigment dispersed. It is particularly preferable from the viewpoint of properties.
In addition, a thermosetting epoxy resin, a melamine resin, a urethane resin, a monomer having two or more photopolymerizable unsaturated bonds in the molecule, and a polymer of the monomer are used as a resin component in the printing ink composition of the present invention. It can be used alone or in combination with an acrylic resin.
Furthermore, a polyfunctional acrylic monomer, for example, a polyfunctional monomer having two or more photopolymerizable unsaturated bonds in the molecule or a thermosetting resin is used in combination with an acrylic resin or a polyester resin. It is also effective. When another resin or a monomer having two or more photopolymerizable unsaturated bonds in the molecule is used in combination, it is preferably used at 200 parts by weight or less with respect to 100 parts by weight of the total amount of the acrylic resin.

  Examples of the acrylic resin include 2-hydroxyethyl (meth) acrylate, glycidyl (meth) acrylate, bis-glycidyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, polyethylene glycol di (meth) acrylate, trimethylolpropane tri ( (Meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, benzyl (meth) acrylate, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, hexyl (meth) Examples include (meth) acrylic esters such as acrylate, octyl (meth) acrylate, and phosphorus-containing (meth) acrylate, and these (meth) acrylic esters and styrene and styrene. Conductor, and copolymers with other polymerizable monomers used. Further, a copolymer of a carboxyl group-containing polymerizable monomer such as itaconic acid, maleic acid, maleic anhydride, maleic acid monoalkyl ester, citraconic acid, citraconic anhydride, citraconic acid monoalkyl ester, and (meth) acrylic acid ester Etc. can be used. (Meth) acrylic acid means acrylic acid or methacrylic acid, and similar terms are also the same.

  Examples of the styrene derivative include α-methylstyrene, m- or p-methoxystyrene, p-hydroxystyrene, 2-methoxy-4-hydroxystyrene, 2-hydroxy-4-methylstyrene, and the like.

Examples of the other polymerizable monomers include N-cyclohexylmaleimide, N-2-methylhexylmaleimide, N-2-ethylcyclohexylmaleimide, N-2-chlorocyclohexylmaleimide, N-phenylmaleimide, N-2-methylphenylmaleimide, N-2-ethylphenylmaleimide, N-2-chlorophenylmaleimide, dicyclopentenyl (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, tricyclo [5.2.1.0 ^2,6 ] decanyl group And (meth) acrylic acid esters.

  The maleic acid monoalkyl ester is preferably an alkyl group having 1 to 12 carbon atoms, monomethyl maleate, monoethyl maleate, mono-n-propyl maleate, monoisopropyl maleate, mono-n-maleate. Examples include butyl, mono-n-hexyl maleate, mono-n-octyl maleate, mono-2-ethylhexyl maleate, mono-n-nonyl maleate, mono-n-dodecyl maleate, and the like.

  As the citraconic acid monoalkyl ester, those having 1 to 12 carbon atoms in the alkyl group are preferable, and citraconic acid monomethyl, citraconic acid monoethyl, citraconic acid mono-n-propyl, citraconic acid monoisopropyl, citraconic acid mono-n- Examples thereof include butyl, mono-n-hexyl citraconic acid, mono-n-octyl citraconic acid, mono-2-ethylhexyl citraconic acid, mono-n-nonyl citraconic acid, and mono-n-dodecyl citraconic acid.

When an acrylic resin is used as the resin component used in the printing ink composition of the present invention, the weight average molecular weight is preferably in the range of 1,500 to 200,000, and 1,500 to 100,000. More preferably, it is in the range of 2,000 to 50,000. When the weight average molecular weight of the acrylic resin is 1,500 or more, suitable pigment dispersibility is obtained, and when it is 200,000 or less, sufficient solubility in a solvent is obtained.
As the acrylic resin having a weight average molecular weight of 1,500 to 200,000, those containing two kinds of monomer components (I) 2-hydroxyethyl methacrylate and (II) methacrylic acid or methyl methacrylate are suitable. Furthermore, an acrylic resin containing a copolymerizable (meth) acrylic monomer having one or more benzene rings in the unit molecule (III) as a monomer component is preferable from the viewpoint of dispersion stability of the pigment.
In the present specification, the weight average molecular weight is a value measured by gel permeation chromatography and converted using a standard polystyrene calibration curve.

  Moreover, as a resin component used for the printing ink composition of this invention, you may use what has light or a thermopolymerizable unsaturated bond. Preferred examples of such resins include glycidyl (meth) acrylate, allyl glycidyl ether, α-ethyl glycidyl (meth) acrylate, crotonyl glycidyl ether, monoalkyl glycidyl itaconate as a high acid value carboxyl group-containing acrylic resin. Compounds having an oxirane ring such as ether and one ethylenically unsaturated bond, allyl alcohol, 2-buten-4-ol, furfuryl alcohol, oleyl alcohol, cinnamyl alcohol, 2-hydroxyethyl (meth) acrylate, Resin in which a hydroxyl group such as N-methylol (meth) acrylamide and a compound each having one ethylenically unsaturated bond (unsaturated alcohol) are reacted; a carboxyl group-containing resin having a hydroxyl group and a free isocyanate group-containing unsaturated compound A resin obtained by reacting an addition reaction product of an epoxy resin and an unsaturated carboxylic acid with a polybasic acid anhydride; addition of a conjugated diene polymer or conjugated diene copolymer and an unsaturated dicarboxylic acid anhydride Examples thereof include a resin obtained by reacting a reaction product with a hydroxyl group-containing polymerizable monomer.

  Examples of the monomer having two or more photopolymerizable unsaturated bonds in the molecule include ethylene oxide (hereinafter referred to as “EO”) modified bisphenol A di (meth) acrylate and epichlorohydrin (hereinafter referred to as “ECH”). .) Modified bisphenol A di (meth) acrylate, bisphenol A di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,3-butylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, Glycerol di (meth) acrylate, neopentyl glycol di (meth) acrylate, EO-modified phosphoric acid di (meth) acrylate, ECH-modified phthalic acid di (meth) acrylate, polyethylene glycol 400 di (meth) acrylate, polypropylene glycol 4 0 di (meth) acrylate, tetraethylene glycol di (meth) acrylate, ECH modified 1,6-hexanediol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, EO modified phosphorus Acid tri (meth) acrylate, EO-modified trimethylolpropane tri (meth) acrylate, propylene oxide (hereinafter referred to as “PO”)-modified trimethylolpropane tri (meth) acrylate, tris ((meth) acryloxyethyl) isocyanurate, Pentaerythritol tetra (meth) acrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, dipentaerythritol penta (meth) acrylate (Meth) acrylate and the like. These monomers can be used alone or in combination of two or more.

  In the ink composition of the present invention, the content of the resin component is preferably in the range of 30 to 60% by weight based on the total amount of the ink composition. When the resin component is 30% by weight or more, the dispersion stability of the pigment increases. On the other hand, when the resin component is 60% by weight or less, the color does not become light due to excessive resin component. From the above points, the resin component content is more preferably in the range of 40 to 50% by weight based on the total amount of the ink composition.

The solvent used in the printing ink composition of the present invention preferably contains propylene glycol monomethyl ether acetate. This is because, for example, it is difficult to finely disperse the pigment with a hydrocarbon solvent, whereas when a high-boiling alkylene glycol ether such as propylene glycol monomethyl ether acetate is used as the solvent, the fine dispersion of the pigment becomes relatively easy. It is.
The content of propylene glycol monomethyl ether acetate is preferably 20% by weight or more, more preferably 40% by weight or more, and still more preferably 50% by weight or more in the solvent. When the content is 20% by weight or more, the dispersion stability of the pigment is high, and the formation of a high-definition pattern that is a problem in the printing method, the pattern accuracy, and the shape are good. Further, the propylene glycol monomethyl ether acetate is excellent in terms of cost as a solvent used when dispersing the pigment.

A high-boiling alcohol-based or ether-based organic solvent of 100 ° C. to 250 ° C. can be used to substitute or partially substitute for propylene glycol monomethyl ether acetate. The high boiling point alcohol is not particularly limited as long as it is 100 ° C. or higher.
Examples of the ether organic solvent include alkylene glycol ether compounds other than propylene glycol monomethyl ether acetate. Specifically, diethylene glycol ethyl ether, diethylene glycol diethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol Monopropyl ether, propylene glycol monobutyl ether, diethylene glycol methyl ether acetate, diethylene glycol ethyl ether acetate, diethylene glycol propyl ether acetate, diethylene glycol isopropyl ether acetate, diethylene glycol butyl ether acetate, diethylene glycol-t-butyl ether acetate Triethylene glycol methyl ether acetate, triethylene glycol ethyl ether acetate, triethylene glycol propyl ether acetate, triethylene glycol isopropyl ether acetate, triethylene glycol butyl ether acetate, triethylene glycol tert-butyl ether acetate, dipropylene glycol Examples thereof include dimethyl ether and dipropylene glycol monobutyl ether.

  In addition to propylene glycol monomethyl ether acetate, the solvent used in the present invention preferably contains one or more hydrocarbon solvents, ester solvents, alcohol solvents, ketone solvents and the like. These solvents are preferably low-boiling solvents from the viewpoint of the drying properties of the coating film.

  Examples of the hydrocarbon solvent include nonpolar hydrocarbon organic solvents such as pentane, hexane, heptane, octane, decane, dodecane, isopentane, isohexane, isooctane, cyclohexane, methylcyclohexane, and cyclopentane. The hydrocarbon solvents may be used alone or in combination of two or more. For example, Exxon Mobile chemical's ISOPAR H, ISOPAR H Fluid, ISOPAR G, ISOPAR L, ISOPAR L Fluid, and the like can be used.

  Examples of ester solvents, alcohol solvents, and ketone solvents include methyl formate, ethyl formate, propyl formate, methyl acetate, ethyl acetate, i-propyl acetate, n-propyl acetate, i-butyl acetate, n-butyl acetate, Ester solvents such as methyl propionate and ethyl propionate; alcohol solvents such as methanol, ethanol, propanol, isopropanol, secondary butanol and tertiary butanol; ketone solvents such as acetone and methyl ethyl ketone can be used.

  These solvents are important for the drying property of the coating film, and the drying property of the coating film is lowered when the solvent has a high boiling point. When a hydrocarbon solvent is used, it is preferably combined with an ester solvent, an alcohol solvent or a ketone solvent because of poor compatibility with various resin components.

  The organic solvent is preferably used at least 100 parts by weight at the time of dispersion with respect to 100 parts by weight of the total amount of the pigment and the resin component at the time of dispersion. When the amount is 100 parts by weight or more, the viscosity at the time of dispersion can be lowered, and particularly when dispersed by a ball mill, a sand mill, a bead mill or the like, it can be easily dispersed.

The viscosity of the printing ink composition of the present invention is 50 mPa.s. s or less, and the viscosity is 50 mPa.s. A uniform coating film can be easily obtained as it is s or less. From the above points, the viscosity of the ink composition is 20 mPa.s. s or less is more preferable, and 10 mPa.s. More preferable is s or less.
The lower limit of the viscosity of the printing ink composition of the present invention is 1 Pa. From the point that a uniform coating film can be easily produced. It is preferable that it is s or more.
In addition, after setting it as a coating film, it is not limited to the said viscosity, It provides as a transfer film and should just form a uniform coating film by transfer on a silicon resin surface or a silicon blanket.

  When the printing ink composition of the present invention is cured with ultraviolet rays, it is possible to use a photoinitiator. For example, as a photoinitiator, benzophenone, N, N′-tetraethyl-4,4′-diaminobenzophenone, 4-methoxy-4′-dimethylaminobenzophenone, benzyl, 2,2-diethoxyacetophenone, benzoin, benzoin methyl ether, Benzoin isobutyl ether, benzyldimethyl ketal, α-hydroxyisobutylphenone, thioxanthone, 2-chlorothioxanthone, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-1-propane , T-butylanthraquinone, 1-chloroanthraquinone, 2,3-dichloroanthraquinone, 3-chloro-2-methylanthraquinone, 2-ethylanthraquinone, 1,4-naphthoquinone, 9,10-phenane Rakinon, 1,2-anthraquinone, 1,4-dimethyl anthraquinone, 2-phenyl anthraquinone, 2- (o-chlorophenyl) -4,5 the like and diphenyl imidazole dimer. These photoinitiators are used individually or in combination of 2 or more types.

  In addition, titanate coupling agents for improving adhesion to the substrate (silane coupling agents having vinyl group, epoxy group, amino group, mercapto group, isopropyltrimethacryloyl titanate, diisopropylisostearoyl-4-aminobenzoyl) Titanates, etc.), surfactants (fluorine-based, silicon-based, hydrocarbon-based, etc.) for improving the smoothness of the film, and other additives such as UV absorbers and antioxidants as needed. can do.

  In the production of the printing ink composition of the present invention, the pigment is mixed and dispersed with a resin, an organic solvent, and, if necessary, a dispersant. Next, the mixture in which the pigment is dispersed is preferably subjected to a dispersion treatment by kneading using a dispersion / kneading apparatus such as an ultrasonic dispersing machine, a three-roll mill, a ball mill, a sand mill, a bead mill, a homogenizer, or a kneader.

  Dispersants added as necessary include anionic dispersants such as polycarboxylic acid type polymer surfactants and polysulfonic acid type polymer surfactants, and nonionics such as polyoxyethylene / polyoxypropylene block polymers Examples thereof include organic dye derivatives in which a substituent such as a carboxyl group, a sulfonate group, a carboxylic acid amide group, or a hydroxyl group is introduced into a dispersant, an organic dye such as anthraquinone, perylene, phthalocyanine, or quinacridone.

  It is preferable to use the above-described dispersing materials and organic dye derivatives since the dispersibility and dispersion stability of the pigment are improved. These pigment dispersants and organic pigment derivatives are preferably used in an amount of 50 parts by weight or less based on 100 parts by weight of the pigment. If it is 50 parts by weight or less, the chromaticity will not change.

  As described above, the organic solvent is at least 100 parts by weight at the time of dispersion with respect to 100 parts by weight of the pigment and the resin component at the time of dispersion, and is dispersed by a ball mill, sand mill, bead mill, etc. A precursor of the composition is produced.

In order to obtain a composition for printing ink, a resin component and a solvent are further added. Here, by adding a thermosetting resin such as a polyfunctional acrylic monomer, a melamine resin, an epoxy resin, or a urethane resin as described above. Thermosetting can be imparted to the composition.
The total amount of the solvent excluding the hydrocarbon solvent may be used together with the pigment during the dispersion treatment, or a part of the solvent may be added after the dispersion treatment.

Next, a printing method using the printing ink composition of the present invention will be described. These printing methods are generally called reverse offset methods.
As shown in FIG. 1, the printing ink composition 1 is applied to a roll-shaped silicon resin surface 3 formed on the surface of the main cylinder 2 using a cap coater 7 or the like. The cap coater 7 supplies the printing composition using capillary action. After air drying for several minutes, the roll or flat convex plate is pressed using the plate cylinder 4 to transfer and remove the unnecessary printing ink composition 1. Thereafter, the remaining printing ink composition 1 is transferred from the roll-shaped silicon resin surface 3 to the surface of the substrate 6 to obtain a desired pattern. In FIG. 1, reference numeral 5 denotes a printing plate.

  The substrate 6 is selected depending on the application, for example, a transparent glass plate such as white plate glass, blue plate glass, silica-coated blue plate glass, a synthetic resin sheet such as a polyester resin, a polycarbonate resin, an acrylic resin, or a vinyl chloride resin. , Films or plates, aluminum plates, copper plates, nickel plates, stainless steel plates and other metal plates, other ceramic plates, semiconductor substrates having photoelectric conversion elements, and the like. These substrates may be previously formed with a black matrix by chromium vapor deposition or the like.

  The thickness of the ink composition layer thus formed is appropriately determined depending on the use, but is preferably in the range of 0.1 to 10 μm. Moreover, when using for a color filter, it is preferable to set it as the range of 0.2-5 micrometers.

The ink composition layer formed on the substrate is sufficiently cured by heat treatment at 200 to 250 ° C. for 30 to 60 minutes.
It is preferable to repeat such a colored image forming process for different colored images of 3 to 4 colors. For example, colored images of red, green, and blue are formed on a black matrix previously formed by chromium vapor deposition or the like. Further, after forming a black matrix using a black colored image forming material, red, green and blue colored images are formed.

  The color filter of the present invention can be efficiently manufactured by using the printing method using the printing ink composition of the present invention. That is, the production of the color filter of the present invention includes the application step of applying the printing ink composition 1 of the present invention to the silicon resin surface 3 to form an application surface, and a relief plate formed in a predetermined shape on the application surface. The printing plate 5 is pressed to remove the printing ink composition 1 on the convex portions of the relief printing, and the transfer step of transferring the printing ink composition 1 remaining on the coated surface to the substrate 6.

EXAMPLES Next, although an Example demonstrates this invention in detail, this invention is not restrict | limited by these.
Example 1
(A) Production of printing ink composition 1 To 78 g of propylene glycol monomethyl ether acetate, C.I. I. 100 g of a dispersion (1) containing 15 g of Pigment Red 254 was prepared.
Next, 35 g of dispersion (1), 5 g of ethyl acetate dispersion of colloidal silica as a filler (solid content 30% by weight, product name EAC-ST, manufactured by Nissan Chemical Industries, Ltd.), hexamethylol-melamine resin (Mitsui Cytec Co., Ltd.) Made by trade name, Cymel 300), 15 g of propylene glycol monomethyl ether acetate and 11 g of ethyl acetate were mixed with a mixer to obtain a red printing ink composition 1. The pigment concentration of the obtained printing ink composition 1 is 39% by weight (calculated value) in terms of solid content (composition excluding the solvent of the printing ink composition 1), and the filler is similarly 11% in terms of solid content. % (Calculated value), and the position of the peak top of the peak showing the maximum value in the particle size distribution of the pigment and the filler was 200 nm and 10 nm, respectively.

(B) Production of Colored Image This printing ink composition 1 was applied to a silicon resin surface (blanket) 3 using a cap coater 7 as shown in FIG. The film was dried for 2 minutes to form a film having a thickness of 1.0 μm. Then, the coating film of the unnecessary part was removed using the plate cylinder 4, and it transcribe | transferred to the glass substrate surface. The accuracy and shape of the transferred pattern was observed with a microscope. The pattern was a 50 μm stripe, and it was evaluated whether it was rectangular or not, and whether the edge was in a clean straight line or not.

Example 2
(A) Production of printing ink composition 2 To 78 g of propylene glycol monomethyl ether acetate, C.I. I. 100 g of a dispersion (2) containing 15 g of Pigment Red 254 was prepared.
Next, 35 g of dispersion (2), 8 g of propylene glycol monomethyl ether acetate dispersion of silicon oxide as a filler (solid content 20% by weight, manufactured by CI Kasei Co., Ltd.), hexamethylol melamine resin (manufactured by Mitsui Cytec Co., Ltd., product) No. Cymel 300) 4.4 g, propylene glycol monomethyl ether acetate 6.7 g and ethyl acetate 14 g were mixed with a mixer to obtain a red printing ink composition 2. The pigment concentration of the obtained printing ink composition 2 is 39% by weight (calculated value) in terms of solid content (composition excluding the solvent of the printing ink composition 2), and the filler is similarly 11% in terms of solid content. % (Calculated value), and the peak top positions of the peaks indicating the maximum values in the particle size distribution of the pigment and filler were 96 nm and 90 nm, respectively.
(B) Production of Colored Image Using the printing ink composition 2 obtained above, a pattern was formed by removing unnecessary portions of the coating film on the glass surface through the same steps as in Example 1 below.

Example 3
(A) Production of printing ink composition 3 To 78 g of propylene glycol monomethyl ether acetate, C.I. I. 100 g of a dispersion (3) containing 15 g of Pigment Red 254 was prepared.
Next, 45 g of dispersion (3), ethyl acetate dispersion of colloidal silica as filler (solid content 30% by weight, manufactured by Nissan Chemical Industries, trade name EAC-ST), 2.2 g of dipentaerythritol hexaacrylate 2 as a monomer 0.7 g, 7 g of propylene glycol monomethyl ether acetate and 13 g of ethyl acetate were mixed with a mixer to obtain a red printing ink composition 3. The pigment concentration of the obtained printing ink composition 3 is 50% by weight (calculated value) in terms of solid content (composition excluding the solvent of the printing ink composition 3), and the filler is also 5% in terms of solid content. % (Calculated value), and the positions of the peak tops of the peaks indicating the maximum values in the particle size distribution of the pigment and the filler were 96 nm and 10 nm, respectively.
(B) Production of Colored Image Using the printing ink composition 3 obtained above, a pattern in which an unnecessary portion of the coating film was removed on the glass surface through the same steps as in Example 1 was formed.

Example 4
(A) Production of printing ink composition 4 To 78 g of propylene glycol monomethyl ether acetate, C.I. I. A dispersion (4) 100 g containing 15 g of Pigment Red 254 was prepared.
Next, 35 g of dispersion (4), ethyl acetate dispersion of colloidal silica as filler (solid content 30 wt%, manufactured by Nissan Chemical Industries, trade name EAC-ST) 2.2 g, dipentaerythritol hexaacrylate 4 as monomer 0.9 g, 15 g of propylene glycol monomethyl ether acetate and 13 g of ethyl acetate were mixed with a mixer to obtain a red printing ink composition 4. The pigment concentration of the resulting printing ink composition 4 is 39% by weight (calculated value) in terms of solid content (composition excluding the solvent of the printing ink composition 4), and the filler is also 5% in terms of solid content. % (Calculated value), and the positions of the peak tops of the peaks indicating the maximum values in the particle size distribution of the pigment and the filler were 96 nm and 10 nm, respectively.
(B) Manufacture of a colored image Using the printing ink composition 4 obtained above, the pattern which removed the coating film of the unnecessary part was formed in the glass surface through the process similar to Example 1 below.

Example 5
(A) Production of printing ink composition 5 To 43.8 g of propylene glycol monomethyl ether acetate and 29.2 g of ethyl acetate, C.I. I. A dispersion (5) 100 g containing 15 g of Pigment Blue 15: 6 was prepared.
Next, 37.8 g of dispersion (5), 1.8 g of colloidal silica ethyl acetate dispersion (solid content 30% by weight, manufactured by Nissan Chemical Industries, trade name EAC-ST) as a filler, dipentaerythritol hexa as a monomer 2.2 g of acrylate and 28 g of propylene glycol monomethyl ether acetate were added and mixed with a mixer to obtain a blue printing ink composition 5. The pigment concentration of the obtained printing ink composition 5 is 52.6% by weight (calculated value) in terms of solid content (composition excluding the solvent of the printing ink composition 5), and the filler is also in terms of solid content. The peak top position of the peak indicating the maximum value in the particle size distribution of the pigment and filler was 5% by weight (calculated value) was 71 nm and 10 nm, respectively.
(B) Production of Colored Image This printing ink composition 5 was applied on a silicon resin surface (blanket) 3 using a cap coater 7 as shown in FIG. The film was dried for 1 minute to form a film having a film thickness of 1.0 μm. Then, the pattern which removed the coating film of the unnecessary part on the glass surface through the process similar to Example 1 was formed.

Comparative Example 1
(A) Production of printing ink composition 6 To 60 g of propylene glycol monomethyl ether acetate and 20 g of ethyl acetate, C.I. I. Pigment Yellow 138 (6 g) and C.I. I. 100 g of a dispersion (6) containing 9 g of Pigment Green 36 was prepared.
Next, 40 g of dispersion (6), 2.5 g of HKY1 acrylic resin manufactured by Soken Chemical Co., Ltd., 2.5 g of dipentaerythritol hexaacrylate, 18.6 g of propylene glycol monomethyl ether acetate and 6.2 g of ethyl acetate as a monomer were mixed in a mixer. As a result, a green printing ink composition 6 was obtained. The obtained printing ink composition 6 has a pigment concentration of 45% by weight (calculated value) in terms of solid content (a composition excluding the solvent of the printing ink composition 6), and is a peak indicating the maximum value in the particle size distribution of the pigment. The peak top position was 120 nm.
(B) Manufacture of a colored image Using the printing ink composition 6 obtained above, the pattern which removed the coating film of the unnecessary part was formed in the glass surface through the process similar to Example 1 below.

Comparative Example 2
(A) Production of printing ink composition 7 To 78 g of propylene glycol monomethyl ether acetate, C.I. I. 100 g of a dispersion (7) containing 15 g of Pigment Red 254 was prepared.
Next, 35 g of dispersion liquid (7), 5.7 g of hexamethylol melamine resin (trade name: Cymel 300, manufactured by Mitsui Cytec Co., Ltd.), 15 g of propylene glycol monomethyl ether acetate and 14 g of ethyl acetate are mixed with a mixer, and red printing is performed. Ink composition 7 was obtained. The pigment concentration of the obtained printing ink composition 7 is 39% by weight (calculated value) in terms of solid content (composition excluding the solvent of the printing ink composition), and is a peak indicating the maximum value in the particle size distribution of the pigment. The peak top position was 200 nm.
(B) Production of Colored Image Using the printing ink composition 7 obtained above, a pattern was formed by removing unnecessary portions of the coating film on the glass surface through the same steps as in Example 1 below.

  Table 1 summarizes the comparison of the appearance and pattern shape of the coating films obtained in each Example and each Comparative Example. The summarized results are shown in Table 1.

The printing ink composition of the present invention can improve the formation of high-definition patterns, pattern accuracy and shape, which are problems in the printing method, and can finely stabilize pigments, and as a printing ink for color filters It is suitable.
In addition, the color filter produced by the method of the present invention can finely stabilize the pigment, and can improve the formation and shape of a high-definition pattern.

It is the schematic for demonstrating a coating process, a removal process, and a transfer process using a printing ink composition.

Explanation of symbols

1 Printing Ink Composition 2 Main Cylinder 3 Silicone Resin Surface (Blanket)
4 Plate cylinder 5 Printing plate 6 Substrate 7 Cap coater

Claims (8)

  In the printing ink composition used for the reversal offset method including a pigment, a filler, a resin component, and a solvent, the pigment content is 20 to 55% by weight in terms of solid content, and shows the maximum value in the particle size distribution of the pigment. The peak top position of the peak is 50 nm to less than 500 nm, the filler content is 5 to 40% by weight in terms of solid content, and the peak peak top showing the maximum value in the particle size distribution of the filler A printing ink composition having a position of less than 10 to 100 nm.   The printing ink composition according to claim 1, wherein the total content of the pigment and the filler is 40 to 70% by weight in terms of solid content.   The printing ink according to claim 1 or 2, wherein the solvent contains propylene glycol monomethyl ether acetate and additionally contains at least one selected from the group consisting of hydrocarbon solvents, ester solvents, alcohol solvents, and ketone solvents. Composition.   The printing ink composition according to claim 1, wherein the filler is a metal oxide, a metal nitride, or a mixture thereof.   The resin component is at least selected from the group consisting of acrylic resins, epoxy resins, melamine resins, polyester resins, urethane resins, alkyd resins, monomers having two or more photopolymerizable unsaturated bonds in the molecule, and polymers of the monomers. It is 1 type, The printing ink composition in any one of Claims 1-4.   Viscosity is 50 mPa * s or less, The printing ink composition in any one of Claims 1-5.   The printing ink composition according to claim 1, which is for a color filter.   An application step of applying the printing ink composition according to any one of claims 1 to 7 to a silicon resin surface to form an application surface, and pressing the relief plate formed in a predetermined shape against the application surface. A method for producing a color filter comprising a removing step of transferring and removing the printing ink composition on the convex portions of the ink and a transferring step of transferring the printing ink composition remaining on the coated surface to the substrate.

Images