JP5294698B2 - Colored photosensitive resin composition for color filter and color filter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a colored photosensitive resin composition for color filter which has a high remaining film rate with minimized developing residue in an unexposed part. <P>SOLUTION: The colored photosensitive resin composition for color filter includes at least a pigment, a binder resin, a multifunctional monomer, a photopolymerization initiator, a dispersant, and a solvent. The binder resin includes a copolymer having a main chain structure obtained by copolymerizing at least an alkylcyclohexyl (meth)acrylate having an alkylcyclohexyl group and a monomer having an acid group, and the hydroxyl value of the copolymer ranges from 15 mgKOH/g to 200 mgKOH/g. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a colored photosensitive resin composition for a color filter having a small amount of development residue in an unexposed area and a high residual film ratio in an exposed area.

A color filter used in a liquid crystal display device is generally transparent so as to partition a transparent substrate, a colored layer formed on the transparent substrate, which is composed of colored patterns of three primary colors of red, green, and blue, and each colored pattern. And a light shielding portion formed on the substrate.
As a method for forming such a colored layer, for example, a photolithography method using a photosensitive resin composition for a colored layer containing a colorant such as a pigment or a dye is known. When a colored layer is formed on a transparent substrate by a photolithography method, a residue of the photosensitive resin composition for the colored layer may adhere to the transparent substrate, and the residue of the photosensitive resin composition for the colored layer is a color filter. If it exists on the surface, it may cause a decrease in transmittance, contrast, display failure, etc., and if it remains on the pattern edge, it may cause peeling of the ITO film or deterioration of the sealing performance in the liquid crystal cell process. There is a problem that a problem occurs that affects the subsequent process.

  In recent years, in order to improve the color reproducibility of a color filter, the photosensitive resin composition for a colored layer used in such a photolithography method has been required to have a high concentration of the pigment contained therein. As the concentration increases, the components that contribute to the color layer forming properties such as photosensitivity and solubility are relatively reduced. As a result, the problem that the colored layer photosensitive resin composition tends to remain after development (increase in development residue), and the degree of cure of the cured product obtained by exposing the photosensitive resin composition for colored layer is insufficient. Thus, there is a problem (decrease in the remaining film ratio) that the cured product is eluted during development.

In order to solve such a problem, Patent Document 1 uses a copolymer of methacrylic acid and benzyl methacrylate having an acid value and a weight average molecular weight within a predetermined range, and reduces residues at unexposed portions during development. A colored photosensitive resin composition is disclosed.
However, even the method disclosed in Patent Document 1 has a problem that the generation of development residues cannot be sufficiently suppressed. Further, there is a problem that it is difficult to make the degree of cure of the cured product after exposure sufficiently high, and the remaining film rate becomes low.

JP 2003-149810 A

  The present invention has been made in view of the above problems, and has as its main object to provide a colored photosensitive resin composition for a color filter having a small amount of development residue at an unexposed location and a high residual film ratio at an exposed location. To do.

  The present invention is a colored photosensitive resin composition for a color filter having at least a pigment, a binder resin, a polyfunctional monomer, a photopolymerization initiator, a dispersant, and a solvent, wherein the binder resin has an alkylcyclohexyl group. Including a copolymer having a main chain structure in which an alkylcyclohexyl (meth) acrylate and a monomer having an acid group are copolymerized at least, and the hydroxyl value of the copolymer is in the range of 15 mgKOH / g to 200 mgKOH / g. The present invention provides a colored photosensitive resin composition for a color filter (hereinafter sometimes simply referred to as a colored photosensitive resin composition).

According to the present invention, since the copolymer contained in the binder resin has a main chain structure in which at least a structural unit containing alkylcyclohexyl (meth) acrylate is copolymerized, development at an unexposed portion is performed. The residue can be reduced.
Further, when the hydroxyl value of the copolymer is in the range of 15 mgKOH / g to 200 mgKOH / g, it can be made excellent in developability and curability, and the remaining film ratio at the exposed portion is improved. be able to. In addition, for this reason, when the colored layer of the color filter is formed using the colored photosensitive resin composition of the present invention, the pigment concentration can be increased because of excellent developability and curability. The color reproducibility can be high.

  In this invention, it is preferable that content of the alkyl cyclohexyl group contained in the said copolymer exists in the range of 15 mass%-90 mass% in the said copolymer. This is because when the content of the alkylcyclohexyl group contained in the copolymer is within the above-described range, the development residue at an unexposed portion can be reduced.

  In the present invention, the alkylcyclohexyl (meth) acrylate is preferably tert-butylcyclohexyl (meth) acrylate, ethylcyclohexyl (meth) acrylate, or isopropylcyclohexyl (meth) acrylate. Since the alkylcyclohexyl (meth) acrylate contains at least one of tert-butylcyclohexyl (meth) acrylate, ethylcyclohexyl (meth) acrylate, and isopropylcyclohexyl (meth) acrylate, there are fewer development residues in unexposed areas. Because it can be.

In the present invention, the above copolymer is obtained by adding a compound having an epoxy group to an acid group-containing copolymer obtained by copolymerizing at least an alkylcyclohexyl (meth) acrylate and a monomer having an acid group. An epoxy compound addition copolymer may be used.
Further, the copolymer may be a hydroxyl group-containing monomer copolymer obtained by copolymerization of an alkylcyclohexyl (meth) acrylate, a monomer having an acid group, and a monomer having a hydroxyl group.
This is because such a copolymer makes it easy to adjust the hydroxyl group content.

  In this invention, it is preferable that the acid value of the said copolymer exists in the range of 50 mgKOH / g-150 mgKOH / g. Since the acid value of the copolymer is within the above-described range, it can be excellent in solubility in an alkaline aqueous solution, so that the time required for development can be shortened, and further development can be achieved. This is because the form can be a dissolved type. This is because by using the dissolution type, it is possible to suppress the occurrence of defects due to re-adhesion of undissolved substances that are likely to occur in the peelable development mode.

  In this invention, it is preferable that the molecular weight of the said copolymer exists in the range of 5000-20000. When the molecular weight of the copolymer is within the above-described range, it can be excellent in solubility in an alkaline aqueous solution, so that the time required for development can be shortened, and the development mode This is because can be made into a dissolved type.

  The present invention provides a color filter having a colored layer formed using the colored photosensitive resin composition for a color filter.

  According to the present invention, since it has a colored layer formed using the colored photosensitive resin composition for a color filter, the color filter of the present invention is used for the colored photosensitive resin composition in an unexposed area. There can be little development residue. Moreover, since the colored photosensitive resin composition for color filters can increase the pigment concentration, it has high color reproducibility by having a colored layer formed using such a colored photosensitive resin composition. Can be.

  The present invention has an effect of providing a colored photosensitive resin composition for a color filter having a small amount of development residue in an unexposed area and a high residual film ratio in an exposed area.

  The present invention relates to a colored photosensitive resin composition for a color filter and a color filter using the same. Hereinafter, the colored photosensitive resin composition for a color filter and the color filter of the present invention will be described.

A. Colored photosensitive resin composition for color filter First, the colored photosensitive resin composition for color filter of the present invention will be described. The colored photosensitive resin composition for a color filter of the present invention has at least a pigment, a binder resin, a polyfunctional monomer, a photopolymerization initiator, a dispersant, and a solvent, and the binder resin is an alkyl having an alkylcyclohexyl group. A copolymer having a main chain structure in which cyclohexyl (meth) acrylate and a monomer having an acid group are copolymerized at least, and the hydroxyl value of the copolymer is within a range of 15 mgKOH / g to 200 mgKOH / g. It is characterized by being.

According to the present invention, since the copolymer contained in the binder resin has a main chain structure in which at least a constituent unit containing alkylcyclohexyl (meth) acrylate is copolymerized, a development residue in an unexposed area Can be reduced.
Further, when the hydroxyl value of the copolymer is in the range of 15 mgKOH / g to 200 mgKOH / g, it can be made excellent in developability and curability. For this reason, it is possible to improve the remaining film ratio at the exposed portion. In addition, from the above, when the colored layer of the color filter is formed using the colored photosensitive resin composition of the present invention, the pigment concentration of the colored layer can be increased. Color reproducibility can be improved.
Here, the copolymer contained in the binder resin has the above-described effects by having the alkylcyclohexyl (meth) acrylate as a structural unit and the hydroxyl value of the copolymer being in the above range. The reason is estimated as follows.

  That is, since the conventional binder resin is not sufficiently hydrophobic, when a colored layer is formed using the colored photosensitive resin composition containing the binder resin, the alkaline development process relatively quickly in the alkaline aqueous solution. Dissolve. For this reason, a material having low solubility in an alkaline aqueous solution such as a pigment contained in the colored photosensitive resin composition is left on the color filter and becomes a development residue.

  On the other hand, the copolymer contained in the binder resin contains alkylcyclohexyl (meth) acrylate as a constituent unit constituting the main chain structure. In addition, since such an alkylcyclohexyl (meth) acrylate has a structure in which an alkyl group is added to a cyclohexyl group, it is relatively strong in hydrophobicity and can suppress solubility in an alkaline aqueous solution. Moreover, since the binder resin contains such a copolymer, the binder resin can have high affinity with a material having low solubility in an alkaline aqueous solution such as a pigment. For this reason, at the time of alkali development processing, the binder resin can be gradually dissolved in the alkaline aqueous solution with a material having low solubility in the alkaline aqueous solution such as a pigment contained in the colored photosensitive resin composition. . Therefore, the material having low solubility in the alkaline aqueous solution such as the pigment is easily removed. As a result, when the colored layer of the color filter is formed using the colored photosensitive resin composition of the present invention, the development residue of the colored photosensitive resin composition in the unexposed area can be reduced. .

In addition, since the copolymer contains a hydroxyl group, the affinity with the developer is improved, the development time can be shortened, the affinity with the photopolymerization initiator is improved, and the curability of the exposed portion is increased. There is. For this reason, it can be made excellent in developability and curability by including such a hydroxyl group so that the hydroxyl value is in the above-described range.
Here, by being excellent in developability, the colored photosensitive resin composition in the unexposed portion can be easily dissolved in the developer, and can be developed (removed) in a short time.
Further, by being excellent in curability, a cured product obtained by exposing and curing the colored photosensitive resin composition can be sufficiently cured, and it is possible to suppress elution into the developer during development. be able to.
Therefore, it is possible to improve the remaining film rate at the exposed location. In addition, for this reason, the colored photosensitive resin composition of the present invention can have good developability and curability even when the pigment concentration is high, so that the color filter has good color reproducibility. It can be.
On the other hand, if the hydroxyl value of the copolymer is out of the above range, that is, less than 15 mg KOH / g, the developability is poor, and if it exceeds 200 mg KOH / g, the remaining film ratio is lowered.

  Hereinafter, each component contained in the colored photosensitive resin composition for a color filter of the present invention will be described.

1. Binder resin The binder resin contained in the colored photosensitive resin composition for a color filter of the present invention contains the above copolymer.

(1) Copolymer The copolymer contained in the binder resin used in the present invention is a main chain obtained by copolymerizing at least an alkylcyclohexyl (meth) acrylate having an alkylcyclohexyl group and a monomer having an acid group. It has a structure and a hydroxyl value is in the range of 15 mgKOH / g to 200 mgKOH / g.
That is, the copolymer has an alkylcyclohexyl group, an acid group, and a hydroxyl group.

Examples of such a copolymer include (1) an epoxy in which a compound having an epoxy group is added to an acid group-containing copolymer obtained by copolymerizing an alkylcyclohexyl (meth) acrylate and a monomer having an acid group. A compound addition copolymer, or (2) a hydroxyl group-containing monomer copolymer obtained by copolymerization of an alkylcyclohexyl (meth) acrylate, a monomer having an acid group, and a monomer having a hydroxyl group can be used. This is because such a copolymer makes it easy to adjust the hydroxyl group content.
In the present invention, an epoxy compound addition copolymer is particularly preferable. This is because the content of the hydroxyl group can be easily adjusted and the copolymer can be excellent in homogeneity and curability.

(A) Epoxy compound addition copolymer The epoxy compound addition copolymer used as the copolymer in the present invention is an acid group-containing copolymer obtained by copolymerizing an alkylcyclohexyl (meth) acrylate and a monomer having an acid group. A polymer is added with a compound having an epoxy group.

(I) Acid group-containing copolymer The acid group-containing copolymer in the present invention is obtained by copolymerizing an alkylcyclohexyl (meth) acrylate and a monomer having an acid group.

a. Alkylcyclohexyl (meth) acrylate The alkylcyclohexyl (meth) acrylate in the present invention is one in which an alkyl group is bonded to the cyclohexyl group of cyclohexyl (meth) acrylate.

  In the present invention, the development residue can be reduced by having alkylcyclohexyl (meth) acrylate as a structural unit.

  The alkyl group in the present invention is not particularly limited as long as it can be the above alkylcyclohexyl (meth) acrylate, but preferably has a carbon number in the range of 1 to 4, However, it is preferably in the range of 2-4. When the carbon number is larger than the above range, the hydrophobicity of the binder resin becomes too strong. The development mode is not a dissolution type in which the colored layer forming layer composed of the colored photosensitive resin composition is gradually dissolved, but the colored photosensitive resin composition lump is peeled off from the color filter. This is because there is a risk of becoming a peelable mold that is developed in the next step. For this reason, it is because the lump of the colored layer forming layer may reattach to the color filter as a development foreign substance and cause a decrease in quality. Moreover, it is because there exists a possibility that sufficient residue reduction effect may not be acquired if it is smaller than the said range.

  Moreover, as a coupling | bonding location of the said alkyl substituent, what is necessary is just a location which can couple | bond the said alkyl substituent.

Specific examples of the alkylcyclohexyl (meth) acrylate having such an alkyl group include tert-butylcyclohexyl (meth) acrylate, ethylcyclohexyl (meth) acrylate, isopropylcyclohexyl (meth) acrylate, isobutylcyclohexyl (meth) acrylate, And methyl cyclohexyl (meth) acrylate. Among them, tert-butylcyclohexyl (meth) acrylate, ethylcyclohexyl (meth) acrylate, isopropylcyclohexyl (meth) acrylate can be preferably used, and in particular, tert-butylcyclohexyl (meta) ) Acrylates can be preferably used. When the colored layer of the color filter is formed using the colored photosensitive resin composition of the present invention because the alkylcyclohexyl (meth) acrylate is the compound described above, the development residue at the unexposed portion is less. Because it can be.
In the present invention, one or more of the above alkylcyclohexyl (meth) acrylates can be used.

  The epoxy compound addition copolymer in the present invention, that is, the content of the alkylcyclohexyl group contained in the copolymer is not particularly limited as long as it exhibits a desired developability, but 15 mass in the copolymer. % To 90% by mass, preferably 40% to 85% by mass, particularly 50% to 80% by mass. This is because when the content of the alkylcyclohexyl group is within the above range, the number of development residues at unexposed portions can be reduced.

b. Monomer having an acid group The monomer having an acid group in the present invention has an ethylenically unsaturated double bond, can be copolymerized with the above-described alkylcyclohexyl (meth) acrylate, and has an acid group. .

  In this invention, it can be made excellent in alkali solubility by having the monomer which has the said acid group as a structural unit. As a result, the time required for development can be shortened, and the development form can be a dissolution type.

  In the present invention, the acid group contained in the monomer having an acid group is not particularly limited as long as it is a functional group that exhibits acidity in water, but a carboxyl group is usually used.

Specific examples of such a monomer having an acid group include (meth) acrylic acid, a dimer of acrylic acid, itaconic acid, crotonic acid, maleic acid, fumaric acid, and anhydrides thereof. In the present invention, (meth) acrylic acid can be preferably used.
In the present invention, one or more of the above can be used.

c. Acid group-containing copolymer The acid group-containing copolymer in the present invention may be a random copolymer in which the alkylcyclohexyl (meth) acrylate and a monomer having an acid group are randomly arranged, and the alkylcyclohexyl ( The block copolymer which has the area | region which the monomer which has a meth) acrylate and an acid group each superposed | polymerized continuously may be sufficient.

  The acid group-containing copolymer in the present invention may be any copolymer obtained by copolymerization of the above-described alkylcyclohexyl (meth) acrylate and a monomer having an acid group. It may be included as a unit.

  Such other monomers may be any monomers that can be copolymerized with the above alkylcyclohexyl (meth) acrylate and the monomer having an acid group. Specifically, methyl (meth) acrylate, ethyl (meth) acrylate, n -Propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, sec-butyl (meth) acrylate, isobutyl (meth) acrylate, tert-butyl (meth) acrylate, n-pentyl (meth) acrylate , N-hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate, n-decyl (meth) acrylate, benzyl (meth) acrylate, isobornyl (meth) acrylate, dicyclopentanie (Meth) acrylate, dicyclopentenyl (meth) acrylate, benzyl maleimide, cyclohexyl maleimide, phenyl maleimide, styrene, can be mentioned γ- methylstyrene.

  The method for producing an acid group-containing copolymer in the present invention is particularly limited as long as it is a method capable of copolymerizing the above-described alkylcyclohexyl (meth) acrylate and a monomer having an acid group as constituent units. Instead, known polymerization methods can be used. Specifically, radical polymerization, anionic polymerization, living radical polymerization, and the like, which are methods generally used for polymerization of a compound having a vinyl group, can be used.

(Ii) Compound having an epoxy group The compound having an epoxy group in the present invention may be any compound that has an epoxy group and can be added to the acid group-containing copolymer described above.
By reacting the acid group contained in the acid group-containing copolymer with the epoxy group to produce a hydroxyl group, it can have excellent developability and curability, and the remaining film ratio at the exposed location. It is because it can be made high.

  Specific examples of the compound having an epoxy group include glycidyl (meth) acrylate, 3,4-epoxycyclohexylmethyl (meth) acrylate, and 1,2-epoxy-4-vinylcyclohexane. Among these, in the present invention, glycidyl (meth) acrylate and 3,4-epoxycyclohexylmethyl (meth) acrylate can be preferably used, and glycidyl (meth) acrylate can be particularly preferably used. Since the compound having the epoxy group is the above-described compound, it is excellent in reactivity with the acid group contained in the acid group-containing copolymer, and therefore the amount of the hydroxyl group to be introduced can be easily adjusted. is there. Moreover, since an ethylenically unsaturated double bond is also added, it can be made more excellent in curability. As a result, the remaining film ratio at the exposed portion can be further increased.

(Iii) Epoxy compound addition copolymer The epoxy compound addition copolymer in the present invention, that is, the hydroxyl value of the copolymer is in the range of 15 mgKOH / g to 200 mgKOH / g, and in the present invention, It is preferably within the range of 15 mgKOH / g to 110 mgKOH / g, and particularly preferably within the range of 20 mgKOH / g to 70 mgKOH / g. When the hydroxyl value of the copolymer is within the above range, it can be excellent in curability. Further, as a result, the remaining film ratio at the exposed portion can be made high.
Such adjustment of the hydroxyl value can be carried out by adjusting the addition amount of the compound having an epoxy group. The hydroxyl value can be determined according to JIS-K0070.

The acid value of the epoxy compound addition copolymer in the present invention is not particularly limited as long as it exhibits a desired developability, but is preferably in the range of 50 mgKOH / g to 150 mgKOH / g, and in particular, 60 mgKOH / g. It is preferably in the range of ˜130 mg KOH / g, and particularly preferably in the range of 70 mg KOH / g to 110 mg KOH / g. When the acid value is within the above range, the solubility in an alkaline aqueous solution can be improved, so that the time required for development can be shortened, and the development form is a dissolution type. Because it can. This is because by using the dissolution type, it is possible to suppress the occurrence of defects due to re-adhesion of undissolved substances that are likely to occur in the peelable development mode.
On the other hand, if it is larger than the above range, the solubility in an aqueous alkali solution is too high, so when the colored layer of the color filter is formed using the colored photosensitive resin composition of the present invention, the pattern of the exposed portion is missing. This is because the adhesion may be reduced. On the other hand, if it is smaller than the above range, the solubility in an alkaline aqueous solution is low, and the time required for development may be long.
Such adjustment of the acid value can be carried out by adjusting the composition ratio of the monomer having an acid group and the addition amount of the compound having an epoxy group.

The molecular weight of the epoxy compound addition copolymer in the present invention is not particularly limited as long as it can exhibit the desired developability, but is preferably in the range of 5000 to 20000, and more preferably in the range of 6000 to 18000. It is preferable that it is in the range, and it is especially preferable that it exists in the range of 7000-15000. When the molecular weight is within the above range, the solubility in an alkaline aqueous solution can be improved, so that the time required for development can be shortened, and the development form is a dissolution type. Because it can.
Further, if it is smaller than the above range, the solubility in an aqueous alkali solution is too high, so when the colored layer of the color filter is formed using the colored photosensitive resin composition of the present invention, the colored layer that is the exposed portion This is because there is a possibility that the pattern may be lost or the adhesiveness may be lowered by dissolving. On the other hand, if it is larger than the above range, the solubility in an alkaline aqueous solution is low, and the time required for development becomes long, that is, the developability may be lowered.
In addition, the said molecular weight is a weight average molecular weight (Mw), The said weight average molecular weight can be calculated | required as a standard polystyrene conversion value with a gel permeation chromatography (GPC).

As content of the epoxy compound addition copolymer in this invention, what is necessary is just to be able to form the colored layer which has a desired degree of hardening, but in the range of 5 mass%-60 mass% in solid content. It is preferable that it is in the range of 10 mass%-40 mass% especially. This is because when the content of the epoxy compound addition copolymer is within the above range, the development residue in the unexposed area is small and the remaining film ratio in the exposed area can be high.
In addition, solid content means all components other than a solvent.

(B) Hydroxyl group-containing monomer copolymer The hydroxyl group-containing monomer copolymer in the present invention is obtained by copolymerization of alkylcyclohexyl (meth) acrylate, a monomer having an acid group, and a monomer having a hydroxyl group.
The alkylcyclohexyl (meth) acrylate and the monomer having an acid group can be the same as those in the “(a) epoxy compound addition copolymer”, and thus the description thereof is omitted here.

The hydroxyl group-containing monomer in the present invention has an ethylenically unsaturated double bond, can be copolymerized with the above-mentioned alkylcyclohexyl (meth) acrylate and a monomer having an acid group, and has a hydroxyl group.
In this invention, it can be made excellent in developability and sclerosis | hardenability by having the monomer which has the said hydroxyl group as a structural unit. As a result, the remaining film ratio at the exposed portion can be made high.

Specific examples of such a hydroxyl group-containing monomer include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 2-hydroxy-3-phenoxypropyl (meth) ) Acrylates.
In the present invention, among them, 2-hydroxyethyl (meth) acrylate and 2-hydroxypropyl (meth) acrylate can be preferably used, and 2-hydroxyethyl (meth) acrylate can be particularly preferably used. When the monomer having a hydroxyl group is the above compound, it can be excellent in curability. As a result, the remaining film ratio at the exposed portion can be made high. Further, it is possible to copolymerize with the above-described alkylcyclohexyl (meth) acrylate and the monomer having an acid group with high accuracy.
In the present invention, one or more of the above can be used.

  The hydroxyl group-containing monomer copolymer in the present invention may be a random copolymer in which an alkylcyclohexyl (meth) acrylate, a monomer having an acid group, and a monomer having a hydroxyl group are randomly arranged, and the above alkylcyclohexyl (meth). A block copolymer having a region in which an acrylate, an acid group-containing monomer, and a hydroxyl group-containing monomer are successively polymerized may be used.

The hydroxyl group-containing monomer copolymer in the present invention is obtained by copolymerization of the above alkylcyclohexyl (meth) acrylate, a monomer having an acid group, and a hydroxyl group-containing monomer. May be included.
Such other monomers can be the same as those in the above “(a) epoxy compound addition copolymer”.

  The hydroxyl value, acid value, molecular weight, content, and alkylcyclohexyl group content of the hydroxyl group-containing monomer copolymer in the present invention may be the same as those in the above “(a) epoxy compound addition copolymer”. Since it is possible, explanation here is omitted.

  The method for producing a hydroxyl group-containing monomer copolymer in the present invention is particularly limited as long as it is a method capable of copolymerizing the above-described alkylcyclohexyl (meth) acrylate, a monomer having an acid group and a monomer having a hydroxyl group as a structural unit. It can be made to be the same as that of the manufacturing method of the said acid group containing copolymer.

(2) Binder resin The binder resin contained in the colored photosensitive resin composition for a color filter of the present invention contains at least the above copolymer, but may contain other resins as necessary. .
As such other resins, those generally used for color filters can be used. Specifically, epoxy resins, acrylic resins, urethane resins, polyester resins, polyimide resins, Photosensitive or non-photosensitive resins such as polyolefin resin and novolac resin can be exemplified.

2. Pigment As the pigment used in the present invention, a known pigment can be used. Specific examples of organic pigments that can be used in the present invention are shown in Tables 1 and 2 below.

Examples of inorganic pigments that can be used include titanium oxide, zinc white, lead sulfate, yellow lead, zinc yellow, bengara, cadmium red, ultramarine, bitumen, chromium oxide green, cobalt green, amber, titanium black, and synthetic iron black. And carbon black.
In addition, these pigments may be used independently and may mix and use 2 or more types.

  Further, the dispersion average particle diameter of the pigment used in the present invention is not particularly limited as long as a desired color can be formed when the colored layer of the color filter is formed using the colored photosensitive resin composition of the present invention. It is not limited, but usually it is preferably in the range of 0.01 μm to 0.15 μm, and particularly preferably in the range of 0.01 μm to 0.10 μm. This is because when a colored layer of a color filter is formed using the colored photosensitive resin composition of the present invention, a colored layer having excellent luminance and contrast can be obtained.

  The content of the pigment used in the present invention is particularly limited as long as a desired color can be formed when the colored layer of the color filter is formed using the colored photosensitive resin composition of the present invention. However, depending on the type of pigment used, the solid content of the colored photosensitive resin composition is preferably in the range of 1% by mass to 70% by mass, and more preferably 10% by mass to 60% by mass. It is preferable to be within the range. When the content of the pigment is more than the above range, when a colored layer of the color filter is formed by using the colored photosensitive resin composition of the present invention, development residue may be generated or developability may be lowered. Because there is. Further, if the amount is less than the above range, when the colored layer of the color filter is formed using the colored photosensitive resin composition of the present invention, the colored layer may not be sufficiently colored. is there.

3. Polyfunctional monomer The polyfunctional monomer contained in the colored photosensitive resin composition for a color filter of the present invention is not particularly limited as long as it can be polymerized with the binder resin. It contains two or more unsaturated double bonds.
As such a polyfunctional monomer, among them, a polyfunctional (meth) acrylate having an acryloyl group or a methacryloyl group is preferable.

  Examples of the polyfunctional (meth) acrylate include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, hexanediol di (meth) acrylate, long chain aliphatic di (meth) acrylate, neopentyl glycol di ( (Meth) acrylate, hydroxypivalate neopentyl glycol di (meth) acrylate, pentaerythritol di (meth) acrylate, stearic acid modified pentaerythritol di (meth) acrylate, propylene di (meth) acrylate, glycerol di (meth) acrylate, tri Ethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, tetramethylene glycol di (meth) acrylate, butylene glycol di (meth) a Relate, dicyclopentanyl di (meth) acrylate, polyethylene glycol di (meth) acrylate, polypropylene di (meth) acrylate, triglycerol di (meth) acrylate, neopentyl glycol modified trimethylolpropane di (meth) acrylate, allylation Cyclohexyl di (meth) acrylate, methoxylated cyclohexyl di (meth) acrylate, acrylated isocyanurate, bis (acryloxyneopentyl glycol) adipate, bisphenol A di (meth) acrylate, tetrabromobisphenol A di (meth) acrylate, bisphenol S di (meth) acrylate, butanediol di (meth) acrylate, phthalic acid di (meth) acrylate, phosphoric acid di (meth) acrylate, zinc di ( Difunctional (meth) acrylate of data) acrylate.

  Examples of the polyfunctional (meth) acrylate include trimethylolpropane tri (meth) acrylate, trimethylolethane tri (meth) acrylate, glycerol tri (meth) acrylate, pentaerythritol tri (meth) acrylate, and alkyl-modified dipentaerythritol. Tri (meth) acrylate, phosphoric acid tri (meth) acrylate, tris (acryloxyethyl) isocyanurate, tris (methacryloxyethyl) isocyanurate, pentaerythritol tetra (meth) acrylate, dipentaerythritol tetra (meth) acrylate, ditri Methylolpropane tetra (meth) acrylate, alkyl-modified dipentaerythritol tetra (meth) acrylate, dipentaerythritol monohydroxypenta (Meth) acrylate, dipentaerythritol hexa (meth) acrylate, dipentaerythritol penta (meth) acrylate, alkyl-modified dipentaerythritol penta (meth) acrylate, urethane tri (meth) acrylate, ester tri (meth) acrylate, urethane hexa ( Trifunctional or higher functional (meth) acrylates such as (meth) acrylate, ester hexa (meth) acrylate, and succinic acid-modified dipentaerythritol penta (meth) acrylate may be mentioned.

  These polyfunctional (meth) acrylates may be used alone or in combination of two or more.

  In particular, when the photo-curing property (high sensitivity) is required for the colored photosensitive resin composition of the present invention, the polyfunctional (meth) acrylate has two polymerizable double bonds in one molecule. It is preferable to have (bifunctional) or more, and more preferably three (trifunctional) or more.

  It is preferable that content of the said polyfunctional monomer exists in the range of 5 mass%-60 mass% with respect to solid content in a coloring photosensitive resin composition, More preferably, 10 mass%-40 mass% Is within the range. This is because if the content of the polyfunctional monomer is too small, curing does not proceed sufficiently and the exposed portion may be eluted. Further, if the content of the compound having the polyfunctional monomer is too large, it may be impossible to develop even at an unexposed portion.

4). Dispersant The dispersant used in the present invention may be any dispersant that can uniformly disperse the pigment, and known dispersants can be used. Specific examples include polymer dispersants such as modified polyurethane, modified polyacrylate, modified polyester, and modified polyamide, and surfactants and pigment derivatives such as phosphate esters, alkylamines, and polyoxyethylene alkylphenyl ethers. . Among these, a polymer dispersant is preferable in the present invention, and specific product names include EFKA-4046, EFKA-4047, EFKA polymer 100, EFKA polymer 400, EFKA polymer 401, EFKA polymer 4300, and EFKA polymer. 4330, (above, manufactured by Ciba Specialty Chemicals), Disperbyk 111, Disperbyk 161, Disperbyk 165, Disperbyk 167, Disperbyk 182, Disperbyk 2000, Disperbyk 2001, SP 000, ER , PB822 (Ajinomoto Fa Ntekuno Co., Ltd.), and the like.

  The content of the dispersant used in the present invention is not particularly limited as long as it can uniformly disperse the pigment described later, but in the solid content of the colored photosensitive resin composition of the present invention. In addition, it is preferably in the range of 0.5% by mass to 30% by mass, and more preferably in the range of 1% by mass to 20% by mass. When the content of the dispersant is smaller than the above range, it is difficult to uniformly disperse the pigment. When the content is larger than the above range, the developability of the colored photosensitive resin composition is reduced or unexposed. This is because there is a possibility that the development residue at the location may increase.

5. Photopolymerization initiator As the photopolymerization initiator used in the present invention, those generally used for the production of color filters can be used.

  Specific examples of such photopolymerization initiators include compounds that generate free radicals by the energy of ultraviolet rays, and derivatives such as benzophenone derivatives such as benzoin and benzophenone or esters thereof; xanthone, diethylthioxanthone, and isopropyl Thioxanthone derivatives such as thioxanthone; oxime ester compounds such as Irgacure OXE-01, Irgacure OXE-02 (above Ciba, Specialty Chemicals), ADEKA OPT-N-1919 (Asahi Denka), chlorosulfonyl, chloromethyl polynuclear aromatic Compounds, halogen-containing compounds such as chloromethyl heterocyclic compounds and chloromethylbenzophenones; triazines; fluorenones; haloalkanes; redox bonds of photoreductive dyes and reducing agents Examples thereof include organic compounds, organic sulfur compounds, and peroxides.

Moreover, the photoinitiator which has a tertiary amine structure can be used. Since the photopolymerization initiator having a tertiary amine structure has a tertiary amine structure that is an oxygen quencher in the molecule, radicals generated from the photopolymerization initiator are not easily deactivated by oxygen, and sensitivity can be improved. It has the advantage that it can.
As a commercial item of the photoinitiator which has the said tertiary amine structure, Irgacure 907, Irgacure 369 (above, Ciba Specialty Chemicals make), high cure ABP (made by Kawaguchi Pharmaceutical) etc. are mentioned, for example.

  In the present invention, a combination of Irgacure 907, Irgacure 369, High Cure ABP, and Diethylthioxanthone can be suitably used. It is because it can be excellent in adhesiveness, curability, and developability.

  As content of the photoinitiator used for this invention, what is necessary is just what can form the colored layer of a color filter, However, 3 mass in solid content of the colored photosensitive resin composition of this invention is sufficient. It is preferable to be in the range of% to 40% by mass, and it is particularly preferable to be in the range of 5% to 35% by mass. This is because if the content of the photopolymerization initiator is less than the above range, radical polymerization cannot sufficiently proceed, curing becomes insufficient, and curability may be lowered. Moreover, it is because there exists a possibility that side reaction may occur easily and temporal stability may be impaired when it exceeds the said range.

6). Solvent The solvent used in the present invention may be any solvent that does not react with the components of the colored photosensitive resin composition of the present invention and can dissolve or uniformly disperse them. Specifically, cyclohexyl acetate; methoxybutyl acetate (MBA); ethylene glycol monoalkyl ether acetates such as ethylene glycol monomethyl ether acetate; diethylene glycol monoalkyl ethers such as diethylene glycol monomethyl ether and diethylene glycol monoethyl ether; diethylene glycol mono-n Diethylene glycol monoalkyl ether acetates such as butyl ether acetate; propylene glycol monoalkyl ether acetates such as propylene glycol monomethyl ether acetate (PGMEA) and propylene glycol monoethyl ether acetate; other ethers such as diethylene glycol dimethyl ether; cyclohexanone, 2- Hep Non, ketones such as 3-heptanone; Lactic acid alkyl esters such as ethyl 2-hydroxypropionate; 3-methyl-3-methoxybutylpropionate, ethyl 3-methoxypropionate, methyl 3-ethoxypropionate, 3 -Other esters such as ethyl ethoxypropionate, n-butyl acetate, isobutyl acetate, n-amyl formate, isoamyl acetate, n-butyl propionate, ethyl butyrate, isopropyl butyrate, n-butyl butyrate, ethyl pyruvate; γ-butyrolactone, 3-methoxybutanol, 3-methyl-3-methoxybutyl acetate and the like can be mentioned. These solvents may be used alone or in combination of two or more.

  The content of the solvent used in the present invention is not particularly limited as long as the colored layer can be formed with high accuracy, but is usually 70% by mass in the colored photosensitive resin composition. It is preferable to be in the range of -95% by mass, and it is particularly preferable to be in the range of 75% by mass to 90% by mass. This is because when the content of the solvent is within the above range, the coating property can be improved.

7). Colored resin composition The colored photosensitive resin composition for a color filter of the present invention has at least a pigment, a binder resin, a polyfunctional monomer, a photopolymerization initiator, a dispersant, and a solvent. An additive etc. may be included.

  In the present invention, examples of the additive include a sensitizer, a polymerization terminator, a chain transfer agent, a plasticizer, a surfactant, an antifoaming agent, and a silane coupling agent.

  As a method for producing the colored photosensitive resin composition for a color filter of the present invention, the above pigment, binder resin, polyfunctional monomer, photopolymerization initiator, dispersant and solvent can be uniformly mixed or dispersed. There is no particular limitation as long as it is present, and a known mixing or dispersing means can be used.

  Examples of the use of the colored photosensitive resin composition for a color filter of the present invention include a photosensitive resin composition for a colored layer that is used when a colored layer of a color filter is formed using a photolithography method. Especially, when forming a colored layer, it is suitably used for the photosensitive resin composition for colored layers which is required to have little development residue and excellent color reproducibility.

B. Next, the color filter of the present invention will be described. The color filter of this invention has a colored layer formed using the said colored photosensitive resin composition for color filters.

Such a color filter of the present invention will be described with reference to the drawings. FIG. 1 is a schematic sectional view showing an example of the color filter of the present invention. As illustrated in FIG. 1, the color filter 10 is formed in a pattern on the transparent substrate 1, the light-shielding part 2 having an opening, and the light-shielding part 2. And the colored layer 3.
Here, the colored layer is formed using the colored photosensitive resin composition for a color filter described in the section “A. Colored photosensitive resin composition for a color filter”.

According to the present invention, since it has a colored layer formed using the colored photosensitive resin composition for a color filter, the color filter of the present invention is used for the colored photosensitive resin composition in an unexposed area. There can be little development residue.
Moreover, since the colored photosensitive resin composition for color filters can increase the pigment concentration, it has high color reproducibility by having a colored layer formed using such a colored photosensitive resin composition. Can be.
Hereinafter, each configuration of the color filter of the present invention will be described.

1. Colored layer The colored layer used in the present invention is formed using the colored photosensitive resin composition for color filters.

  As an arrangement of the colored layers used in the present invention, a colored layer of a general color filter may have, for example, an arrangement of a stripe type, a mosaic type, a triangle type, a four pixel arrangement type, or the like. It can be. Moreover, the width | variety, area, etc. of a colored layer can be set arbitrarily.

  The thickness of the colored layer is usually preferably in the range of 1 μm to 5 μm.

The colored layer used in the present invention can be formed by a photolithography method in which the colored photosensitive resin composition for a color filter is applied onto a transparent substrate described later, dried, exposed and developed. .
In the present invention, since the colored layer is formed using the above-described colored photosensitive resin composition for a color filter, the color filter of the present invention is used for the color filter colored photosensitive resin in an unexposed area. The development residue of the resin composition can be reduced. Moreover, since the colored photosensitive resin composition for color filters can increase the pigment concentration, it has high color reproducibility by having a colored layer formed using such a colored photosensitive resin composition. Can be.

  The colored photosensitive resin composition for a color filter is the same as the content described in the section “A. Colored photosensitive resin composition for a color filter”, and therefore, the description thereof is omitted here.

2. Color filter The color filter of this invention has a transparent substrate and a light-shielding part normally other than the said colored layer normally. As such a transparent substrate and a light shielding part, those used for general color filters can be used.

  The method for producing the color filter of the present invention is not particularly limited as long as the colored layer is formed by a photolithography method using the colored photosensitive resin composition for a color filter. A color filter manufacturing method can be used.

  The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the present invention has substantially the same configuration as the technical idea described in the claims of the present invention, and any device that exhibits the same function and effect is the present invention. It is included in the technical scope of the invention.

  The following examples illustrate the present invention more specifically.

[Examples 1 to 10 and Comparative Examples 1 to 6]
1. Preparation of binder resin (binder resins A to G, I to K, and M to O)
A polymerization tank was charged with 300 g of solvent and heated to the main chain synthesis temperature shown in Table 3 below in a nitrogen atmosphere, and then t-butylcyclohexyl methacrylate (t-BuCHMA), ethylcyclohexyl methacrylate (EtCHMA), isopropylcyclohexyl methacrylate ( Table 3 below shows i-PrCHMA), methacrylic acid (MAA), cyclohexyl methacrylate (CHMA), styrene (St), benzyl methacrylate (BzMA), 2-hydroxyethyl methacrylate (HEMA), and azoisobutyronitrile (AIBN). Each of the main chain forming mixtures contained in the composition shown was continuously dropped over 1.5 hours.
Thereafter, the reaction was continued while maintaining the main chain synthesis temperature, and p-methoxyphenol was added as a polymerization inhibitor 2 hours after the completion of the dropwise addition of the main chain forming mixture to terminate the polymerization.

Next, while blowing air, glycidyl methacrylate (GMA) (epoxy compound 1) or 3,4-epoxycyclohexylmethyl methacrylate (epoxy compound 2) was added in the composition shown in Table 3 below, and the temperature was raised to 110 ° C. After that, triethylamine was added and an addition reaction was performed at 110 ° C. for 15 hours to obtain a binder resin (solid content: 40% by mass).
As the solvent, propylene glycol monomethyl ether acetate (solvent 1) and a mixed solvent of propylene glycol monomethyl ether acetate / propylene glycol monomethyl ether = 7/3 (solvent 2) were used. Moreover, the numerical value of each component of the mixture for main chain formation in Table 3, an epoxy compound, a triethylamine, and p-methoxyphenol represents the ratio of a mixing | blending in a weight part.

About the obtained binder resin, the weight average molecular weight and the acid value were measured. Moreover, after calculating | requiring the hydroxyl value according to JIS-K0070, the hydroxyl value per 1g of solid content was computed from solid content concentration. The results are shown in Table 4 below.
In addition, the measuring method of a weight average molecular weight measured the weight average molecular weight by Showex GPC system-21H (Shodex GPC System-21H) by using polystyrene as a standard substance and THF as an eluent. Moreover, the method mentioned above was used for the measuring method of an acid value.

(Binder resins H, L and P)
300 g of a solvent is charged in a polymerization tank, and after heating to a main chain synthesis temperature shown in Table 3 below in a nitrogen atmosphere, a main chain forming mixture containing the composition shown in Table 3 is continuously taken for 1.5 hours. Dripped. Thereafter, the main chain synthesis temperature was maintained and the mixture was stirred for 2 hours to obtain a binder resin (solid content: 40% by mass).

2. Colored photosensitive resin composition As Examples 1-10, the said binder resin AJ was used, respectively, and the composition shown below was uniformly mixed and disperse | distributed using the bead mill, and the colored photosensitive resin composition was prepared. Moreover, as Comparative Examples 1 to 6, similarly to the Examples, colored photosensitive resin compositions were prepared using the binder resins K to P, respectively.

<Composition of colored photosensitive resin composition>
-Binder resin: 7.7 parts by weight (in terms of solid content)
Dipentaerystol hexaacrylate (DPHA): 3.3 parts by weight Irgacure 369 (Ciba Specialty Chemicals, IRGACURE 369): 1 part by weight Irgacure 907 (Ciba Specialty Chemicals, IRGACURE 907): 1 part by weight Pigment Red 177 (red pigment, PR 177): 0.7 parts by weight Pigment Red 254 (red pigment, PR 254): 5.6 parts by weight Pigment Yellow 139 (yellow pigment, P.R. 177) Y.139): 0.7 parts by weight-dispersing agent (Bic Chemie, Disperbyk 161): 2.0 parts by weight (in terms of solid content)
Solvent (propylene glycol monomethyl ether acetate): 60.8 parts by weight

[Evaluation]
Using the colored photosensitive resin compositions obtained in Examples and Comparative Examples, a colored layer was formed and evaluated for developability, development residue, adhesion, and remaining film ratio.

1. Formation of Colored Layer After spin-coating the colored photosensitive resin composition on a glass substrate that has been washed with an alkali to form a colored layer forming layer comprising the colored photosensitive resin composition, room temperature for 3 minutes at 80 ° C. Was baked on a hot plate for 3 minutes and dried.
Subsequently, the colored layer forming layer after drying was cured by mask exposure at 100 mJ / cm ² using an ultrahigh pressure mercury lamp.
Next, spin development was performed using 0.05 wt% potassium hydroxide (KOH) as a developing solution, and the developing treatment was performed by allowing the developing solution to indirectly liquid for 60 seconds and then washing with pure water. Thereafter, the patterned substrate was post-baked in an oven at 230 ° C. for 30 minutes. The film thickness of the colored layer comprising the colored layer forming layer after post-baking was 1.9 μm.

2. Evaluation About the colored layer formed using the coloring photosensitive resin composition, evaluation was performed about developability, a development residue, adhesiveness, and a residual film rate.

(1) Developability In the formation of the colored layer, the time until the unexposed portion was dissolved and developed was measured, and evaluation was performed according to the following criteria. The end of development was judged visually. The results are shown in Table 4.
○: Development is completed in 10 seconds to 30 seconds.
Δ: Development is completed in 31 to 60 seconds.
*: Development is not completed within 60 seconds.

(2) Development residue The glass substrate after formation of the colored layer was evaluated for the presence or absence of a residue by the following methods: (a) visual evaluation and (b) evaluation after wiping.
(A) Visual evaluation Visual observation was performed in a state where light was irradiated from the surface of the glass substrate after the colored layer was formed by a projector, and the presence or absence of a residue in the unexposed portion (visual observation by the projector) was confirmed. The results are shown in Table 4 below. Here, when no whitening was observed on the glass substrate, it was determined that there was no residue, and when the whitening was slightly observed, the result was Δ, and many whitenings were observed on the glass substrate surface. In some cases, it was judged that there was a residue, and was marked as x.

(B) Evaluation after wiping The unexposed portion (50 mm × 50 mm) of the glass substrate after the formation of the colored layer was sufficiently wiped off with a lens cleaner (Toraysee MK Clean Cloth (registered trademark) manufactured by Toray), The coloring degree of the lens cleaner was visually observed. The results are shown in Table 4. In addition, when the lens cleaner was not colored at all, it was marked as ◯, when the lens cleaner was slightly colored, Δ when the lens cleaner was colored.

(3) Adhesiveness A line pattern having a line width of 1 μm to 100 μm was exposed, the minimum line width of the line pattern in close contact without being dissolved after development was measured, and evaluated according to the following criteria. The results are shown in Table 4.
○: Lines with a line width of 10 μm or less are in close contact.
Δ: A line having a line width greater than 10 μm and 20 μm or less is in close contact.
X: A line having a line width of 20 μm or less does not adhere.

(4) Remaining film ratio The remaining film ratio (%) is calculated by the following calculation method. When it is higher than 80%, it is evaluated as ◯. In the case of less than, it was set as x.
Residual film ratio (%) = (film thickness of colored layer forming layer after post-baking / film thickness of colored layer forming layer after exposure) × 100

  From Table 4, in the Example, it has confirmed that there were few image development residues and the remaining film rate was high. On the other hand, in the comparative example, both the development residue and the remaining film ratio could not be made good.

It is a schematic sectional drawing which shows an example of the color filter of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Board | substrate 2 ... Light-shielding part 3 ... Colored layer 10 ... Color filter

Claims (8)

A colored photosensitive resin composition for a color filter having at least a pigment, a binder resin, a polyfunctional monomer, a photopolymerization initiator, a dispersant, and a solvent,
The binder resin includes a copolymer having a main chain structure in which an alkylcyclohexyl (meth) acrylate having an alkylcyclohexyl group and a monomer having an acid group are copolymerized at least.
The copolymer has a hydroxyl value of 15 mgKOH / g to 160 mgKOH / g,
The molecular weight is 4000-30000,
The acid value is 40 mg KOH / g to 200 mg KOH / g,
The content of the alkylcyclohexyl (meth) acrylate contained in the copolymer is in the range of 15% by mass to 82% by mass in the copolymer,
A colored photosensitive resin composition for a color filter, wherein the alkylcyclohexyl (meth) acrylate contains at least one of tert-butylcyclohexyl (meth) acrylate, ethylcyclohexyl (meth) acrylate and isopropylcyclohexyl (meth) acrylate . 2. The color filter according to claim 1, wherein the content of the alkylcyclohexyl (meth) acrylate contained in the copolymer is in the range of 46 mass% to 82 mass% in the copolymer. Colored photosensitive resin composition. An epoxy compound addition copolymer obtained by adding a compound having an epoxy group to an acid group-containing copolymer obtained by copolymerizing at least an alkylcyclohexyl (meth) acrylate and a monomer having an acid group. The colored photosensitive resin composition for a color filter according to claim 1 or 2, which is a coalescence. The copolymer is a hydroxyl group-containing monomer copolymer obtained by copolymerizing at least an alkylcyclohexyl (meth) acrylate, a monomer having an acid group, and a monomer having a hydroxyl group. The colored photosensitive resin composition for color filters according to claim 2. The colored photosensitive resin for a color filter according to any one of claims 1 to 4, wherein an acid value of the copolymer is in a range of 40 mgKOH / g to 150 mgKOH / g. Composition. The colored photosensitive resin composition for a color filter according to any one of claims 1 to 5, wherein the copolymer has a weight average molecular weight in the range of 5,000 to 20,000. The colored photosensitive resin for a color filter according to any one of claims 1 to 6, wherein the copolymer has a hydroxyl value in a range of 20 mgKOH / g to 110 mgKOH / g. Composition. A color filter comprising a colored layer formed using the colored photosensitive resin composition for a color filter according to any one of claims 1 to 7.

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