JP5665615B2 - Photosensitive resin composition for color filter - Google Patents

Description

  The present invention relates to a photosensitive resin composition for a color filter and a color filter. More specifically, the present invention relates to a photosensitive resin composition used for producing a color filter in a liquid crystal display element, a solid-state imaging element or the like, and a color filter formed using the same.

  The photosensitive resin composition for a color filter is a photosensitive resin composition (permanent negative resist) used for producing a color filter used for a liquid crystal display element, a solid-state imaging element, and the like, and a radical polymerizable compound, It contains a binder resin, a photo radical initiator, a colorant (pigment / pigment dispersant or dye), other additives and a solvent. A color filter in which such a photosensitive resin composition for a color filter is preferably used is a pixel of at least three primary colors (red (R), green (G), and blue (B)) and a resin black matrix ( BM), a protective film, a columnar spacer, and the like. For example, a photosensitive resin composition for a color filter is applied on a substrate, a pattern is formed by exposure and development through a mask, and baking is performed. After being cured by (baking), it can be produced by a method of applying a protective film or the like.

  Conventionally, as a photosensitive resin composition for a color filter, a photosensitive resin composition using a normal (meth) acrylic polymer as a binder is generally used. For example, a (meth) acrylic ester binder resin, a pigment, A photosensitive resin composition for a color filter comprising a dispersant, a photopolymerization initiator, and a photopolymerizable monomer is disclosed (Patent Document 1). However, this technology is inferior in heat resistance and thermal stability, causing deterioration and decomposition in the subsequent heat treatment process, and causing problems such as background stains, reduced coating smoothness, film thickness reduction, and coloring. was there. Moreover, the performance which fully satisfied also about the point of coating-film intensity | strength and exposure sensitivity was not obtained.

  Also, photolithography is used from a photosensitive resin in which a (meth) acryloyl group is introduced by reacting a part of the carboxyl group of a (meth) acrylic acid ester-based polymer having a carboxyl group with glycidyl (meth) acrylate or the like. A technique for producing a columnar spacer in a liquid crystal display device is disclosed (Patent Document 2). However, with this technique, although the exposure sensitivity is improved, it cannot be said that the heat resistance and the coating film strength are sufficient.

  In addition, as demand for color filters grows and demands for high performance increase, demands for quality improvements are also increasing. In particular, in recent years, with an increase in substrate size, a highly sensitive photosensitive resin composition that maintains a pattern shape for a long time in a developing solution in a developing process and does not have a chipped or peeled pattern is required. For this reason, there is a demand for a resin with improved adhesion to the substrate.

Japanese Patent Laid-Open No. 1-152449 JP-A-11-174464

  Therefore, an object of the present invention is to provide a photosensitive resin composition that is excellent in flexibility and further improved in remaining film properties without deteriorating alkali developability, and that is suitably used for color filter production.

As a result of intensive studies, the inventors of the present invention have succeeded in successfully solving the above problems. That is, the present invention is a carboxyl group-containing radical polymerizable copolymer, wherein the carboxyl group is arranged in a side chain separated from the main chain by 7 or more elements, and further has a radical polymerizable double bond in the side chain. It is characterized by that.
The carboxyl group preferably has the structure of the following structural units (a1) and / or (a2).

(In the formula, R ₁ represents hydrogen or a methyl group. R ₂ represents a divalent organic group having 5 to 10 carbon atoms, and may or may not have a substituent. R ₅ represents an alkylene group, which may or may not have a substituent, and R ₆ represents a divalent organic group having 2 to 10 carbon atoms and has a substituent. (It may or may not have. N represents an integer of 1 to 5.)
Moreover, it is preferable that the said carboxy-group containing radically polymerizable copolymer has a structure of the following structural unit (b1) and / or (b2).

(In the formula, R ₁ , R ₂ , R ₅ , R ₆ and n represent the same meaning as in the general formulas (a1) and (a2). R ₃ can react with a carboxyl group in the molecule. This represents a divalent group derived from a monomer having a functional group and a radical polymerizable double bond, and R ₄ represents hydrogen or a methyl group.
The functional group capable of reacting with a carboxyl group in the radical polymerizable copolymer is preferably at least one selected from the group consisting of a glycidyl group, an oxazolinyl group, an isocyanate group, and an oxetanyl group.

The radical polymerizable copolymer preferably has a glass transition temperature of 20 ° C. or lower, a double bond equivalent of 200 to 2000 g / equivalent, and an acid value of 10 to 200 mg KOH / g.
Moreover, this invention is also the photosensitive resin composition for color filters containing said carboxyl group containing radically polymerizable copolymer, a photoinitiator (B), and a coloring agent (C).

  Furthermore, the present invention also includes a color filter characterized by having a coloring pattern using the above-described photosensitive resin composition for color filters.

  The carboxyl group-containing radical polymerizable copolymer of the present invention exhibits good developability even with a small amount of carboxyl groups because the carboxyl groups contributing to developability are separated from the main chain. Furthermore, since it has a radical polymerizable double bond that contributes to photocuring properties, the cured product is also excellent in flexibility.

  As a result, it is possible to provide a photosensitive resin composition for a color filter having a good residual film property with respect to a base material, in which a pattern is not chipped or peeled off.

  First, the carboxyl group-containing radical polymerizable copolymer of the present invention (hereinafter sometimes simply referred to as a radical polymerizable copolymer (A)) will be described in detail. In the radical polymerizable copolymer (A) of the present invention, the carboxyl group is arranged in a side chain separated from the main chain by 7 or more elements, and further has a radical polymerizable double bond in the side chain. Any divalent linking group having a linear or branched alkylene group, oxyalkylene group, ester group, amide group, urethane group or ketone group is not particularly limited as long as the number of elements linking the main chain and the carboxyl group is 7 or more. , Etc. Among these, the case of having an ester group, an amide group or a urethane group is preferred from the viewpoint of synthesis. The radical polymerizable copolymer (A) has a radical polymerizable double bond. If there is no radically polymerizable double bond, polymerization and curing by light (which may be heat) becomes insufficient, and the physical properties of the cured product are inferior. It is more preferable to have two or more radically polymerizable double bonds in one molecule. Although an upper limit is not limited, it can prevent that hardened | cured material becomes weak by adjusting the amount of double bonds suitably according to the molecular weight of resin. In the present invention, the “main chain” is a linking chain formed by the polymerization reaction of the monomer in the radical polymerizable copolymer (A) obtained by the polymerization reaction of the monomer. A linking group with a large number of elements. In the present invention, the carboxyl group-containing radical-polymerizable copolymer has a carboxyl group that contributes to developability and is separated from the main chain. Even in a small amount, good developability is exhibited. Furthermore, since it has a radical polymerizable double bond that contributes to light or thermosetting, it is excellent in flexibility of the cured product.

  In the method of disposing the carboxyl group of the radical polymerizable copolymer (A) of the present invention in the side chain separated from the main chain by 7 or more elements, a monomer having a double bond and a carboxyl group separated by 7 or more elements is used. Examples of the polymerization method include a method in which a monomer having a functional group is reacted with a carboxyl group and a compound having reactivity with the functional group and then the carboxyl group is separated from the main chain by 7 or more elements.

  As a method for polymerizing a monomer in which a double bond and a carboxyl group are separated by 7 or more elements, for example, the following general formula (i) can be preferably used.

(In the formula, R represents 6 to 30 carbon atoms and represents a monomer having a carboxyl group at the terminal.)
In the general formula (i), the substituent R represents a monomer having a carboxyl group having 6 to 30 carbon atoms, and a part of this carboxyl group is doubled with a functional group capable of reacting with the carboxyl group in one molecule. With bonds. A polymer polymerized using the general formula (i) has a carboxyl group at a position far from the main chain, and thus is less susceptible to steric hindrance of the main chain and has high mobility, so even if the amount of the carboxyl group is small (co-polymerization) It exhibits good alkali developability (even if the acid value of the coalescence is relatively small). Since the carboxyl group lowers the hygroscopic resistance of the cured product, it is better that the carboxyl group is less in the range where alkali developability is expressed. In this respect, the carboxyl group at a position far from the main chain is effective.

  As a method for introducing a carboxyl group at a position far from the double bond, a lactone having a 6-membered ring or more is used for chain extension (lactone modification) of the carboxyl group. By this method, sufficient mobility expression and low Tg (glass transition temperature) can be achieved. Examples of the lactone having 6 or more members include δ-valerolactone, ε-caprolactone, and lactones having 8 or more members and may have a substituent such as a methyl group. These can be used alone or in combination of two or more. If the lactone becomes too large, the hydrophobicity of the chain extension portion increases and the alkali developability decreases, so it is preferable to use a lactone having a 12-membered ring or less.

  Monomers (I) having a carboxyl group before lactone modification and constituting the main chain include (meth) acrylic acid, itaconic acid, crotonic acid, cinnamic acid, β- (meth) acryloyloxypropionic acid Among them, (meth) acrylic acid is preferable. An example of a suitable structural unit in the case of polymerizing a monomer modified with a cyclic lactone using (meth) acrylic acid can be represented by the following formula (a1).

(In the formula, R ₁ represents hydrogen or a methyl group, R ₂ represents an optionally substituted divalent alkylene group having 5 to 10 carbon atoms, and n represents an integer of 1 to 5)
If R ₁ is hydrogen, it is a unit derived from acrylic acid before lactone modification, and if R ₁ is a methyl group, it is a unit derived from methacrylic acid before lactone modification. R ₂ is an alkylene group derived from a lactone ring. In addition, when n is 2 or more, that is, when two or more lactones are linked to one carboxyl group, R ₂ may be the same or different. When n exceeds 5, the hydrophobicity of the chain extension portion increases and the developability decreases, so n is preferably 1 to 5. However, in the lactone addition reaction, since the lactone tends to be further added to the terminal carboxyl group generated once the lactone is added, n in the actual radical polymerizable copolymer (A) is an average value, In addition, there may be a unit in which 5 mol or more of lactone is added or not added at all in a chemical reaction. Therefore, the radical polymerizable copolymer (A) of the present invention only needs to contain the unit (a1).

Another preferred method is to add an acid anhydride to the chain extension of the hydroxyl group. Even with this method, sufficient mobility and low Tg (glass transition temperature) can be achieved. Acid anhydrides include hexahydrophthalic anhydride, methyl tetrahydro anhydride, methyl hexahydrophthalic anhydride, methyl nadic anhydride, hydrogenated methyl nadic anhydride, trialkyltetrahydrophthalic anhydride, methylcyclohexene tetracarboxylic dianhydride Products, trimellitic anhydride, pyromellitic acid-free, benzophenone tetracarboxylic dianhydride, aliphatic dibasic acid polyanhydride and the like. These can be used alone or in combination of two or more. Monomers (II) having a hydroxyl group before acid anhydride modification and constituting the main chain include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) ) Acrylate, 2-hydroxyethyl vinyl ether and the like, and one or more of these may be used. Among these, 2-hydroxyethyl acrylate is preferable. Therefore, an example of a suitable structural unit of the radically polymerizable copolymer (A) of the present invention can be represented by the following formula (a2).

(In the formula, R ₁ represents hydrogen or a methyl group. R ₂ represents a divalent organic group having 5 to 10 carbon atoms, and may or may not have a substituent. R ₅ represents an alkylene group, which may or may not have a substituent, and R ₆ represents a divalent organic group having 2 to 10 carbon atoms and has a substituent. (It may or may not have. N represents an integer of 1 to 5.)
In the present invention, a method of reacting a carboxyl group and a compound having reactivity with the functional group after polymerization of the monomer having a functional group is also preferably used. In other words, after polymerizing a monomer having a double bond and a reactive functional group such as a carboxyl group, a hydroxyl group, a glycidyl group, an epoxy group, an oxetane group, an isocyanate group, an amino group, etc., it reacts with the functional group. This is a method in which a carboxyl group is arranged in a side chain that is separated from the main chain by 7 or more elements by using a compound having a. Preferred examples include carboxyl group and cyclic lactone compound, hydroxyl group or amino group and acid anhydride or dibasic acid, glycidyl group, epoxy group or oxetane group and dibasic acid, isocyanate group and hydroxyl group. When the above-mentioned cyclic lactone is reacted with a copolymer obtained by copolymerizing (meth) acrylic acid, the above (a1) is obtained. When the above-mentioned acid anhydride is reacted with a copolymer obtained by copolymerizing a hydroxyl group-containing (meth) acrylic acid, the above (a2) is obtained.

  The radical polymerizable copolymer (A) used in the present invention has a radical polymerizable double bond as an essential side chain. The radically polymerizable copolymer (A) has a curability by having a radically polymerizable double bond in the side chain, and can produce a cured product having good physical properties. The radical polymerizable double bond is preferably a (meth) acryloyl group.

As a method for introducing a radical polymerizable double bond into the side chain of the radical polymerizable copolymer (A), a functional group is introduced into the radical polymerizable copolymer (A), and the radical polymerizable double bond There is a method of introducing a radical polymerizable double bond by reacting a functional group and a reactive compound. Preferred combinations include a combination of a carboxyl group and a glycidyl group, an oxazolinyl group, an isocyanate group, or an oxetanyl group, a combination of a hydroxyl group and an isocyanate group, a combination of an amino group and a carboxyl group, or an acid anhydride group. In addition, the combination of the precursor copolymer of the radically polymerizable copolymer (A), the radically polymerizable double bond, the functional group and the substituent of the compound having reactivity may be reversed.
It is also preferred that a part of the chain-extended carboxyl group is modified with a monomer (III) having a functional group capable of reacting with the carboxyl group and a radical polymerizable double bond in one molecule. In this way, the presence of the radical polymerizable double bond at a position further away from the main chain than the carboxyl group enables the introduced radical polymerizable double bond to be effective without being adversely affected by the steric hindrance of the main chain. Therefore, even if the introduction amount is small, the photocurability is good, and a cured product having good heat resistance and other characteristics can be obtained.

  The unit in which the preferred units (a1) and (a2) are modified with a compound having a functional group capable of reacting with a carboxyl group and a radical polymerizable double bond can be represented by the following formulas (b1) and (b2). The radical polymerizable copolymer of the present invention preferably has units (b1) and / or (b2) together with units (a1) and / or (a2).

(Wherein R ₁ , R ₂ , R ₅ , R ₆ and n represent the same meaning as described above, and R ₃ represents a functional group capable of reacting with a carboxyl group and a radical polymerizable double bond in the molecule. The divalent group derived from the monomer it has, R ₄ represents hydrogen or a methyl group, respectively.)
In the above units (b1) and (b2), R ₃ preferably has 5 or less carbon atoms, and by setting this range, better developability can be obtained.

  The “functional group capable of reacting with a carboxyl group” is preferably one selected from the group consisting of a glycidyl group, an oxazolinyl group, an isocyanate group and an oxetanyl group. The radical polymerizable double bond is preferably a (meth) acryloyl group.

  Specific examples of a compound having a glycidyl group among compounds having a functional group capable of reacting with a carboxyl group and a radical polymerizable double bond include glycidyl (meth) acrylate, allyl glycidyl ether, α-ethylglycidyl (meth) acrylate, 3 , 4-epoxycyclohexylmethyl acrylate (for example, “Cyclomer (registered trademark) A400” manufactured by Daicel Chemical Industries, Ltd.), 3,4-epoxycyclohexylmethyl methacrylate (for example, “Cyclomer M100” manufactured by Daicel Chemical Industries, Ltd.) Etc.).

  Specific examples in the case of having an oxazolinyl group include N-vinyloxazoline and 2-isopropenyl-2-oxazoline.

  Specific examples in the case of having an isocyanate group include (meth) acryloyloxyethyl isocyanate, (meth) acryloyloxyethoxyethyl isocyanate, bis (acryloxymethyl) ethyl isocyanate, and modified products thereof. More specifically, “Karenz MOI” (methacryloyloxyethyl isocyanate), “Karenz AOI” (acryloyloxyethoxyethyl isocyanate), “Karenz MOI-EG” (methacryloyloxyethoxyethyl isocyanate), “Karenz MOI IBM” ( Karenz MOI isocyanate block), "Karenz MOI-BP" (Karenz MOI isocyanate block), and "Karenz BEI" (bis (acryloxymethyl) ethyl isocyanate) are commercially available from Showa Denko. These trade names are registered trademarks.

  Specific examples in the case of having an oxetanyl group include 3- (meth) acryloyloxymethyl oxetane and 3-ethyl-3- (meth) acryloyloxymethyl oxetane.

  In the above preferred structural units (a1) and (b1), the monomer in the copolymer is a unit derived from a (meth) acrylic acid unit, and the structural units (a2) and (b2) are both The monomer in the copolymer is a unit derived from 2-hydroxyethyl acrylate. The radical polymerizable copolymer (A) of the present invention preferably has units other than (a1) (a2) (b1) (b2), and is synthesized using “other monomers”. Is preferred. Adjustment of various physical properties as a resin composition or a cured product becomes easy.

  As other monomer (IV), methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate , Sec-butyl (meth) acrylate, tert-butyl (meth) acrylate, amyl (meth) acrylate, isoamyl (meth) acrylate, heptyl (meth) acrylate, n-octyl (meth) acrylate, isooctyl (meth) acrylate, 2 -Ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, nonyl (meth) acrylate, isononyl (meth) acrylate, isodecyl (meth) acrylate, dodecyl (meth) acrylate, tridecyl (meta Acrylate, n-lauryl (meth) acrylate, n-stearyl (meth) acrylate, isostearyl (meth) acrylate, dicyclopentanyl (meth) acrylate, isobornyl (meth) acrylate, 2-acetoacetoxy (meth) acrylate, phenoxy (Meth) acrylates such as ethyl (meth) acrylate and benzyl (meth) acrylate; unsaturated monobasic acids such as (meth) acrylic acid; styrene, α-methylstyrene, o-vinyltoluene, m-vinyltoluene, p -Aromatics such as vinyltoluene, α-chlorostyrene, o-methoxystyrene, m-methoxystyrene, p-methoxystyrene, o-vinylbenzyl methyl ether, m-vinylbenzyl methyl ether, p-vinylbenzyl methyl ether, indene Bi 2-aminoethyl (meth) acrylate, 2-dimethylaminoethyl (meth) acrylate, 2-aminopropyl (meth) acrylate, 2-dimethylaminopropyl (meth) acrylate, 3-aminopropyl (meth) ) Amino group-containing monomers such as acrylate and 3-dimethylaminopropyl (meth) acrylate; Vinyl acetates such as vinyl acetate, vinyl propionate, vinyl butyrate and vinyl benzoate; Vinyl methyl ether and vinyl ethyl ether Unsaturated ethers such as allyl glycidyl ether; vinyl cyanide compounds such as (meth) acrylonitrile, α-chloroacrylonitrile, vinylidene cyanide; (meth) acrylamide, α-chloroacrylamide, N-2-hydroxyethyl (meth) Acrylic Unsaturated amides such as N-phenylmaleimide, N-cyclohexylmaleimide and N-benzylmaleimide; aliphatic conjugated dienes such as 1,3-butadiene, isoprene and chloroprene; polystyrene, polymethyl Examples thereof include macromonomers having a mono (meth) acryloyl group at the terminal of a polymer molecular chain such as acrylate, polymethyl methacrylate, poly-n-butyl methacrylate, and polysiloxane. The above monomers may be used alone or in combination of two or more.

  Among these, benzyl (meth) acrylate, N-phenylmaleimide, N-cyclohexylmaleimide, N-benzylmaleimide and the like are preferable, and the heat resistance of the cured product is maintained while maintaining the flexibility of the resulting radically polymerizable copolymer. There is no loss.

  Next, the suitable manufacturing method of the radically polymerizable copolymer (A) of this invention is demonstrated. The production method that can be adopted is that the monomer (I) having a carboxyl group and constituting the main chain is subjected to lactone modification, polymerized, and then modified with the monomer (III). There are a first production method in which the copolymer is first produced and a second method in which the copolymer is first produced and then modified with the lactone or the monomer (III).

  In order to cause the lactone to undergo a ring-opening addition reaction with the monomer (I) (preferably (meth) acrylic acid, etc.) having a carboxyl group and constituting the main chain, in the presence of a diluent Or what is necessary is just to make both react at 70-170 degreeC in absence. For the ring-opening addition reaction of lactone, organic titanium compounds such as tetrabutyl titanate, tetrapropyl titanate, and tetraethyl titanate; organic tin compounds such as tin octylate, dibutyltin oxide, dibutyltin dilaurate; stannous chloride, bromide It is preferable to use tin halides such as monotin and stannous iodide; tetrafluoroboric acid, perchloric acid and the like as catalysts.

  At this time, the amount of the lactone relative to the monomer (I) having a carboxyl group is 0.5% depending on the equivalent number of the lactone to be added (corresponding to n in the formula in terms of the unit (a1)). It can be selected from ˜5 equivalents. Note that the lower limit of the amount of lactone is 0.5 equivalent because, as described above, lactone may be further added to the carboxyl group formed by addition of lactone, so that lactone is 0.5 equivalent or more and 1.0 equivalent. This is because n in the unit (a1) may be 1 or more even when used in less than an equivalent amount.

  In the first production method, the amount of the chain-extended carboxyl group in the finally obtained radical-polymerizable copolymer (A) can be adjusted by the amount of monomer used after addition of the lactone at the time of copolymerization. Therefore, the lactone addition reaction to the monomer (I) may be performed so that the lactone is added to all the monomers. However, in the case of a chemical reaction, a monomer having a carboxyl group to which a lactone is not added may be mixed in the reaction product. In the following description, for convenience of description, a reaction product obtained by addition reaction of a lactone with a monomer is referred to as a monomer (V). Monomer (V) obtained by adding lactone to monomer (I) is, for example, “Aronix (registered trademark) M-5300” (ω-carboxy-polycaprolactone monoacrylate; n≈2; Toagosei Co., Ltd. Can also be obtained.

  Subsequently, a polymerization reaction is performed. In the polymerization, the monomer (V) is an essential component, but it is preferable to use one or more of the above-mentioned other monomers (IV) in combination. At this time, the ratio of the monomer (V) to the other monomer (IV) is 5% to 70% by mass of the monomer (V) in 100% by mass of the total monomer components (the balance is the monomer). (IV) is preferable. Since a part of the monomer (V) is later used for introducing a double bond, if it is less than 5% by mass, the radically polymerizable copolymer (A) finally obtained is alkali developable. May not be expressed or the photocurability may be deteriorated. If it exceeds 70% by mass, tack-free property before curing may not be obtained, or the moisture absorption resistance of the cured product may be reduced. As for a monomer (V), 10-60 mass% is more preferable, and 20-50 mass% is further more preferable. Further, even when the monomer (I) and the monomer (IV) are polymerized first by employing the second production method, the range of the preferred amount of the monomer (I) is It becomes the range corresponding to the range of the preferable use amount of the monomer (V).

  The polymerization method is not particularly limited, and for example, a method of polymerizing monomer components using a radical polymerization initiator and a molecular weight regulator as necessary is preferable. In this case, the polymerization can be performed by bulk polymerization, solution polymerization, suspension polymerization, dispersion polymerization, emulsion polymerization, or a combination of these as appropriate. Among these, it is preferable to perform polymerization by solution polymerization. In the solution polymerization, the whole amount may be charged all at once, or a part thereof may be charged in advance in a reaction vessel and the rest may be dropped. Alternatively, the entire amount may be dropped. In terms of controlling the amount of heat generation, it is preferable to prepare a part of the reaction vessel in advance and add the rest dropwise or drop the entire amount.

  Solvents that can be used in the solution polymerization are not particularly limited, and examples include esters such as cellosolve acetate, carbitol acetate, and propylene glycol monomethyl ether acetate; ethers such as diethylene glycol dimethyl ether; cyclic ethers such as tetrahydrofuran; cyclohexanone. And ketones such as methyl ethyl ketone and methyl isobutyl ketone; dimethyl sulfoxide, dimethylformamide; hydrocarbons such as toluene and xylene, and the like. These may be used alone or in combination of two or more.

  As a radical polymerization initiator, 1 type (s) or 2 or more types, such as a peroxide and an azo initiator, can be used, for example. Specifically, for example, cumene hydroperoxide, sometimes isopropylbenzene peroxide, di-t-butyl peroxide, lauroyl peroxide, benzoyl peroxide, t-butylperoxyisopropyl carbonate, t-butylperoxy-2- Organic peroxides such as ethylhexanoate and t-amylperoxy-2-ethylhexanoate; 2,2′-azobis (isobutyronitrile), 1,1′-azobis (cyclohexanecarbonitrile), 2 Azo compounds such as 2,2′-azobis (2,4-dimethylvaleronitrile) and dimethyl-2,2′-azobis (2-methylpropionate); Among these, t-butylperoxy-2-ethylhexanoate and dimethyl-2,2′-azobis (2-methylpropionate) are preferred from the viewpoints of decomposition temperature, availability, and ease of handling. preferable. As for the usage-amount of a radical polymerization initiator, about 0.001-5 mass parts is preferable with respect to 100 mass parts of all the monomer components.

  As the molecular weight regulator, mercaptans such as n-dodecyl mercaptan and mercaptopropionic acid can be used. What is necessary is just to set suitably the temperature, time, etc. of a polymerization reaction according to the kind etc. of a monomer, Usually, it is preferable to superpose | polymerize at about 50-150 degreeC for several hours.

  The molecular weight of the copolymer of the monomer (V) and the monomer (IV) is preferably 1000 or more, more preferably 3000 or more, and further preferably 5000 or more in terms of the weight average molecular weight Mw. If Mw is less than 1000, tack may remain in the coating film before photocuring, and physical properties, particularly heat resistance and mechanical strength of the cured product after photocuring may be insufficient. The upper limit of Mw is preferably 100,000 or less, more preferably 75,000 or less, and even more preferably 50000 or less from the viewpoint of handleability and alkali developability.

  In the case of adopting the second production method described above, the monomer (I) and the monomer (IV) are copolymerized in the same manner as described above, and then the lactone is added under the above-mentioned preferred addition equivalent number and conditions. A ring-opening addition reaction may be performed. Also in this case, it is preferable to adjust Mw of the copolymer obtained from monomer (I) and monomer (IV) to the said range.

When a copolymer having a chain-extended carboxyl group is obtained by either the first production method or the second production method, the copolymer is reacted with the monomer (III). A radical polymerizable double bond introduction reaction is performed for imparting radical polymerizability to. This reaction must be performed after obtaining a copolymer having a chain-extended carboxyl group in order to obtain a radically polymerizable copolymer (A) without polymerizing the double bond of the monomer (III). There is. The double bond introduction reaction is a reaction between the chain-extended carboxyl group of the copolymer and the functional group of the monomer (III). In the presence or absence of a diluent, methyl hydroquinone, oxygen, etc. Polymerization inhibitors, tertiary amines such as triethylamine, quaternary ammonium salts such as triethylbenzylammonium chloride, imidazoles such as 2-ethyl-4-methylimidazole, phosphorus compounds such as triphenylphosphine, metal organic acid salts In the presence of a reaction catalyst such as an inorganic acid salt or a chelate compound, the reaction can usually be performed at about 80 to 130 ° C.
Furthermore, the suitable manufacturing method of the radically polymerizable copolymer (A) of this invention is demonstrated. The production method that can be adopted is that the monomer (II) having a hydroxyl group and constituting the main chain is half-esterified with an acid anhydride, polymerized, and then the monomer ( There are a first production method in which the modification by III) is carried out and a second method in which the copolymer is first produced and then half-esterification or modification by the monomer (III) is carried out.

  Monomer (II) having a hydroxyl group and constituting the main chain (preferably, (2-hydroxyethyl acrylate) is subjected to a half esterification reaction in the presence or absence of a diluent. In the half esterification reaction, in the presence of a polymerization inhibitor such as hydroquinone, monomethyl ether hydroquinone, oxygen, etc., no catalyst, or tertiary amine, The reaction is preferably carried out at 50 to 130 ° C. in the presence of a reaction catalyst such as quaternary phosphine, lithium chloride, quaternary ammonium salt or quaternary phosphonium salt.

  In the first production method, the amount of chain-extended carboxyl groups in the finally obtained radical polymerizable copolymer (A) is the amount of monomer used after addition of acid anhydride at the time of copolymerization. Since it can be adjusted, the addition reaction of the acid anhydride to the monomer (II) may be performed so that the acid anhydride is added to all of the monomer (II). However, in the usual chemical reaction, a monomer having a carboxyl group to which an acid anhydride is not added may be mixed in the reaction product. In the following description, for convenience of description, a reaction product obtained by addition reaction of an acid anhydride with monomer (II) is referred to as monomer (VI). Monomer (VI) obtained by addition reaction of acid anhydride with monomer (II) is obtained, for example, as “light acrylate HOA-MS” (2-acryloyloxyethyl succinic acid; manufactured by Kyoeisha Chemical Co., Ltd.) You can also

  Subsequently, a polymerization reaction is performed, and the conditions are as described above.

  The radically polymerizable copolymer (A) of the present invention preferably has a Tg (glass transition temperature) of 20 ° C. or lower, and the type and amount of the monomer may be appropriately selected. By setting Tg to 20 ° C. or less, sufficient flexibility can be obtained, and adhesion with the base material can be improved to prevent peeling and chipping during development. More preferably, it is 10 degrees C or less, More preferably, it is 0 degrees C or less. Further, the lower limit of Tg is preferably −50 ° C. or higher, more preferably −30 ° C. or higher, and further preferably −20 ° C. or higher, from the viewpoint of tack-free property of the coating film and physical properties of the cured product.

  In the radically polymerizable copolymer (A) of the present invention, the double bond introduction reaction is preferably performed so that the double bond equivalent is 200 to 2000 g / equivalent. The double bond equivalent is related to the photocurability and the physical properties of the cured product. By setting the double bond equivalent in the above range, a cured product having excellent physical properties such as heat resistance, strength, and flexibility can be provided. In addition, a well-balanced photosensitive resin in which photocurability and alkali developability are compatible can be obtained. A more preferable range of the double bond equivalent is 1800 g / equivalent or less, and further preferably 1500 g / equivalent or less.

  When the double bond introduction reaction is carried out so as to be within the preferable double bond equivalent range described above, the unit of monomer (V) or monomer (II) and monomer (VI) has a carboxyl group. The unit disappeared and a double bond was introduced, and the unit containing a carboxyl group. At this time, the amount of the monomer (V) or monomer (II) used and the monomer (VI) so that the acid value of the radical polymerizable copolymer (A) is 10 to 200 mgKOH / g. ) And the amount of monomer (I) are preferably determined. If the acid value is less than 10 mgKOH / g, the alkali developability is lowered, and if it exceeds 200 mgKOH / g, the water resistance of the cured product may be lowered. The acid value is more preferably 20 to 180 mgKOH / g, and further preferably 30 to 150 mgKOH / g. Since the radically polymerizable copolymer (A) of the present invention has a chain-extended carboxyl group, it exhibits excellent alkali developability even when the acid value is set lower than that of a conventional photosensitive resin. To do.

  The amount of the monomer (III) used is in the range of 0.01 to 0.99 equivalents relative to 1 equivalent of the carboxyl group of the copolymer before modification with the monomer (III), and the resulting radicals It is preferable that the double bond equivalent and the acid value of the polymerizable copolymer (A) are determined so as to be in the preferable range. In addition, the suitable range of Mw of the radically polymerizable copolymer (A) of the present invention is the same as the preferred range of the copolymer and Mw before the double bond introduction reaction.

The radically polymerizable copolymer (A) of the present invention can be suitably used for a photosensitive resin composition for a color filter. Usually, the photosensitive resin composition for a color filter contains a photopolymerization initiator and a colorant in addition to the radical polymerizable copolymer (A) of the present invention.
<Photopolymerization initiator (B)>
In the photosensitive resin composition for a color filter of the present invention, the photopolymerization initiator (B) is also an essential component. Next, the photopolymerization initiator (B) will be described.

  A well-known thing can be used as a photoinitiator (B). Specifically, benzoin such as benzoin, benzoin methyl ether, and benzoin ethyl ether and alkyl ethers thereof; acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 1,1-dichloroacetophenone, 4- (1-t- Acetophenones such as butyldioxy-1-methylethyl) acetophenone; anthraquinones such as 2-methylanthraquinone, 2-amylanthraquinone, 2-t-butylanthraquinone, 1-chloroanthraquinone; 2,4-dimethylthioxanthone, 2,4- Thioxanthones such as diisopropylthioxanthone and 2-chlorothioxanthone; Ketals such as acetophenone dimethyl ketal and benzyldimethyl ketal; Benzophenone, 4- (1-t-butyldioxy-1-methyl Benzophenones such as til) benzophenone and 3,3 ′, 4,4′-tetrakis (t-butyldioxycarbonyl) benzophenone; 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinyl-1- Examples include propane (“Irgacure 907”; manufactured by Ciba Japan), 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1, acylphosphine oxides, and xanthones.

  These photopolymerization initiators (B) are used as one or a mixture of two or more, and a total of 100 masses of the radical polymerizable copolymer (A) and the radical polymerizable compound (described later) used as necessary. It is preferable that 0.5-30 mass parts is contained with respect to a part. When the amount of the photopolymerization initiator (B) is less than 0.5 parts by mass, it is necessary to increase the light irradiation time or the polymerization is difficult to occur even if light irradiation is performed. Hardness cannot be obtained. In addition, even if it mixes a photoinitiator exceeding 30 mass parts, there is no merit which uses it in large quantities.

<Colorant (C)>
The photosensitive resin composition for a color filter of the present invention uses a dye / pigment as the colorant (C). From the viewpoint of heat resistance and light resistance, organic or inorganic pigments are preferable. Specifically, organic pigments such as organic compounds classified as pigments in the color index CI (published by The Society of Dyers and Colorists). And inorganic pigments such as metal oxides or composite oxides.

  Moreover, when using a dye as a coloring agent (C), the photosensitive resin composition for color filters can be obtained by melt | dissolving uniformly in the photosensitive resin composition. The dye that can be used is not particularly limited, and conventionally known dyes for color filters can be used.

  These colorants (C) are used alone or as a mixture of two or more thereof, and a total of 100 parts by mass of the radical polymerizable copolymer (A) and the radical polymerizable compound (described later) used as necessary. On the other hand, it is preferable to use 10 to 150 parts by mass. More preferably, it is 20-100 mass parts.

  You may mix | blend radical polymerizable compounds other than the said radical polymerizable copolymer (A) with the photosensitive resin composition for color filters of this invention. Examples of the radical polymerizable compound include a radical polymerizable oligomer and a radical polymerizable monomer. For example, as the radically polymerizable oligomer, unsaturated polyester, epoxy acrylate, urethane acrylate, polyester acrylate, or the like can be used.

  Examples of radically polymerizable monomers include aromatic vinyl monomers such as styrene, α-methylstyrene, α-chlorostyrene, vinyltoluene, divinylbenzene, diallyl phthalate, and diallylbenzenephosphonate; vinyl ester monomers such as vinyl acetate and vinyl adipate Methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, β-hydroxyethyl (meth) acrylate, (2-oxo-1,3-dioxolan-4-yl) -methyl (meth) acrylate, (Di) ethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, trimethylolpropane di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tetra (meth) Acrylate, dipentaerythritol hexa (meth) acrylate, tris (hydroxyethyl) isocyanurate tri (meth) acrylate of (meth) acrylic monomer; triallyl cyanurate and the like can be used. These are appropriately selected according to the required characteristics, and one or more can be used.

  In the photosensitive resin composition for a color filter of the present invention, when the radical polymerizable copolymer (A) and the radical polymerizable compound are used in combination, the radical polymerizable copolymer is obtained when the total of both is 100 parts by mass. It is preferable to use 15 parts by mass or more, more preferably 30 parts by mass or more of the polymer (A). If the amount is small, various effects based on the radical polymerizable copolymer (A) may not be sufficiently exhibited.

  From the viewpoint of workability when the composition of the present invention is applied to a substrate, a solvent may be blended in the composition. Solvents include hydrocarbons such as toluene and xylene; cellosolves such as cellosolve and butylcellosolve; carbitols such as carbitol and butylcarbitol; cellosolve acetate, carbitol acetate, (di) propylene glycol monomethyl ether acetate, etc. Esters; ketones such as methyl isobutyl ketone and methyl ethyl ketone; (di) ethers such as ethylene glycol dimethyl ether. These solvents can be used singly or in combination of two or more, and may be used in an appropriate amount so that the composition has an optimum viscosity during the coating operation. In addition, the copolymer solution obtained by solution polymerization can be used in the composition as it is, diluted or concentrated.

  If necessary, the photosensitive resin composition for color filters of the present invention may be added with known additives such as a dispersant, a sensitizer, a polymerization inhibitor, an adhesion improver, a filler, and a plasticizer. May be.

  The photosensitive resin composition for a color filter of the present invention is usually applied to a substrate by a known method and then pre-baked to evaporate the solvent to form a coating film. Subsequently, after exposing this coating film through a photomask, an unexposed portion is dissolved in an alkaline aqueous solution to perform alkali development. Next, after washing as necessary, post-baking is performed. Thus, a predetermined pattern is formed through application of the composition, pre-baking, exposure, development processing, and post-baking.

  Specific examples of alkalis that can be used for development include alkali metal compounds such as sodium carbonate, potassium carbonate, sodium hydroxide and potassium hydroxide; alkaline earth metal compounds such as calcium hydroxide; ammonia; monomethylamine and dimethylamine Water-soluble organic amines such as trimethylamine, monoethylamine, diethylamine, triethylamine, monopropylamine, dimethylpropylamine, monoethanolamine, diethanolamine, triethanolamine, ethylenediamine, diethylenetriamine, dimethylaminoethyl methacrylate, polyethyleneimine, These 1 type (s) or 2 or more types can be used. In particular, the photosensitive resin composition for a color filter of the present invention contains a radical polymerizable copolymer (A) having a carboxyl group at a position away from the main chain as described above. Alkali development is possible even with a weak alkali such as.

EXAMPLES Hereinafter, although an Example demonstrates this invention, these are only illustrations and this invention is not limited to this. The evaluation in Examples and Comparative Examples was performed as follows. Moreover, the part and% in an example are a mass reference | standard.
<Weight average molecular weight>
Weight average molecular weight was measured by a GPC (gel permeation chromatography) method using HLC-8220GPC (manufactured by Tosoh Corp.) and column TSKgel SuperHZM-M (manufactured by Tosoh Corp.) using polystyrene as a standard substance and tetrahydrofuran as an eluent.
<Solid content>
About 1 g of the polymer solution was weighed into an aluminum cup, dissolved by adding about 3 g of acetone, and then naturally dried at room temperature. Then, using a hot air dryer (trade name: PHH-101, manufactured by ESPEC CORP.), It was dried in a vacuum at 160 ° C. for 3 hours, then allowed to cool in a desiccator, and the weight was measured. From the weight loss, the solid content of the polymer solution was calculated.
<Acid value>
3 g of the resin solution is precisely weighed and dissolved in a mixed solvent of 90 g of acetone / 10 g of water, and an automatic titration apparatus (manufactured by Hiranuma Sangyo Co., Ltd., trade name) using thymol blue as an indicator and 0.1 N KOH aqueous solution as a titrant. : COM-555), the acid value of the polymer solution was measured, and the acid value per gram of the solid content was determined from the acid value of the solution and the solid content of the solution.
<Glass transition temperature (Tg)>
The copolymer solution is applied to a glass substrate, dried at 50 ° C. under reduced pressure for 24 hours, redissolved in acetone, and again dried at 50 ° C. under reduced pressure for 24 hours to remove volatile components. About the obtained solid content, it measured based on JIS-K7121 by DSC (differential scanning calorimeter method, measuring instrument: Seiko DSC6200) under nitrogen stream at the temperature increase rate of 10 degree-C / min.
<Flexibility>
On a PET film fixed on a 10 cm square glass substrate, the transparent resist composition was applied and dried by a spin coater to form a coating film having a dry film thickness of 1.0 μm. This coating film was heated at 100 ° C. for 3 minutes. After heating, a photomask was placed at a distance of 100 μm from the coating film and a UV aligner (model number TME-150RNS manufactured by TOPCON Co., Ltd.) equipped with a 2.0 kW ultra-high pressure mercury lamp at an intensity of 50 mJ / cm 2 (365 nm illuminance conversion). Irradiated with ultraviolet rays. Thereafter, the coating film was heated at 230 ° C. for 30 minutes, and after cooling, the obtained PET film was applied to an iron rod having a diameter of 10 mm, and the state of bending cracks was observed, and evaluated as follows.
○: No cracks occurred △: Some cracks ×: Overall cracks

<Developability of negative resist>
On a 10 cm square glass substrate, the transparent resist composition was applied and dried by a spin coater to form a coating film having a dry film thickness of 1.0 μm. This coating film was heated at 100 ° C. for 3 minutes. After heating, a photomask was placed at a distance of 100 μm from the coating film and a UV aligner (model number TME-150RNS manufactured by TOPCON Co., Ltd.) equipped with a 2.0 kW ultra-high pressure mercury lamp at an intensity of 50 mJ / cm 2 (365 nm illuminance conversion). Irradiated with ultraviolet rays.
After irradiation with ultraviolet rays, a 0.1% potassium hydroxide aqueous solution was sprayed on the coating film with a spin developer to dissolve and remove unexposed portions, and the remaining exposed portions were developed by washing with pure water for 20 seconds. . Then, the developability of the obtained film was evaluated by observing the shape of the pattern with a laser microscope, observing the presence or absence of pattern defects during the development time, and evaluating as follows.
◎: No dissolution defect ○: Less than 10% defect part Δ: Less than 50% defect part <Residual film property>
Similar to the developability evaluation of the negative resist, coating, ultraviolet irradiation, and development are performed, the resulting film is dried, and the ratio of the film pressure after development to the film pressure before development is expressed as a percentage. Rate. Thereby, the degree of the remaining film (resistance) when used as a resist is understood, and the higher the numerical value, the better the remaining film property.

(Example 1-1)
A separable flask with a cooling tube as a reaction vessel was charged with 450 parts of propylene glycol monomethyl ether (PGME) and heated to 90 ° C. in a nitrogen atmosphere. Then, 12 parts of benzyl maleimide and 85 parts of butyl acrylate were added as the dropping system 1. , 53 parts of cyclohexyl methacrylate (CHMA), M-5300 (Aronix (registered trademark) M-5300 (ω-carboxy-polycaprolactone monoacrylate; n≈2; manufactured by Toagosei Co., Ltd.), 80 parts, 46 parts of PGME, perbutyl O ( (Product name, polymerization initiator, manufactured by NOF Corporation) 5 parts, 2 parts of n-dodecyl mercaptan and 38 parts of PGME were continuously supplied as dropping system 3 over 3 hours, and then maintained at 90 ° C. for 30 minutes. The temperature was raised to 115 ° C. and polymerization was continued for 1.5 hours.
Next, 22 parts of glycidyl methacrylate, 0.8 parts of triethylamine as a catalyst, 2,2′-methylenebis (4-methyl-6-tert-butylphenol) as a polymerization inhibitor (trade name “ANTAGE W400”, Kawaguchi, Resin solution 1 having a double bond equivalent of 1687 g / equivalent by adding 0.4 parts and continuing the reaction at 110 ° C. for 14 hours while bubbling nitrogen and oxygen mixed gas (oxygen concentration: 7%). Got.
When various physical properties of the obtained resin solution 1 were measured, the weight average molecular weight was 8,500, the solid concentration obtained by drying at 160 ° C. under vacuum was 31.6%, and the solid content determined by the titration method The acid value per unit was 34 mgKOH / g. The Tg of the resin determined using DSC was −37.1 ° C.
(Example 1-2)
In a separable flask with a cooling tube as a reaction vessel, 839 parts of PGMEA was charged and heated to 90 ° C. in a nitrogen atmosphere. Then, 21 parts of benzyl maleimide, 159 parts of butyl acrylate, and cyclohexyl methacrylate (CHMA) were added as the dropping system 1. 99 parts, 2-acryloyloxyethyl hexahydrophthalic acid (light acrylate HOA-HH manufactured by Kyoeisha Chemical Co., Ltd.) 150 parts, PGMEA 86 parts, perbutyl O (trade name, polymerization initiator, manufactured by NOF Corporation), 9 parts, As the dropping system 3, 4 parts of n-dodecyl mercaptan and 75 parts of PGMEA were continuously supplied over 3 hours. Then, after maintaining at 90 ° C. for 30 minutes, the temperature was raised to 115 ° C. and polymerization was continued for 1.5 hours.
Subsequently, 45 parts of glycidyl methacrylate, 1.4 parts of triethylamine as a catalyst, 2,2′-methylenebis (4-methyl-6-tert-butylphenol) as a polymerization inhibitor (trade name “ANTAGE W400”, Kawaguchi, Resin solution 2 with a double bond equivalent of 1524 g / equivalent by adding 0.7 parts and continuing the reaction at 110 ° C. for 14 hours while bubbling nitrogen and oxygen mixed gas (oxygen concentration: 7%). Got.
When various physical properties of the obtained resin solution 2 were measured, the weight average molecular weight was 16,500, the solid concentration obtained by drying at 160 ° C. under vacuum was 31.8%, and the solid content determined by the titration method The per acid value was 41 mgKOH / g. The Tg of the resin determined using DSC was −16.3 ° C.
(Example 1-3)
In a separable flask with a cooling tube as a reaction tank, 1022 parts of PGMEA was charged and heated to 90 ° C. in a nitrogen atmosphere. Then, 25 parts of benzyl maleimide, 50 parts of cyclohexyl methacrylate (CHMA), M— 5300 (manufactured by Toa Gosei Co., Ltd.) 425 parts, PGME 100 parts, perbutyl O (trade name, polymerization initiator, manufactured by Nippon Oil & Fats Co., Ltd.) 10 parts, dropping system 3 as n-dodecyl mercaptan 15 parts, PGME 45 parts 3 Feeded continuously over time. Then, after maintaining at 90 ° C. for 30 minutes, the temperature was raised to 115 ° C. and polymerization was continued for 1.5 hours.
Next, 166 parts of glycidyl methacrylate, 2 parts of triethylamine as a catalyst, 2,2′-methylenebis (4-methyl-6-tert-butylphenol) as a polymerization inhibitor (trade name “ANTAGE W400”, Kawaguchi Chemical Industries, Ltd.) 1 part) was added, and the reaction was continued at 110 ° C. for 14 hours while bubbling nitrogen and oxygen mixed gas (oxygen concentration: 7%) to obtain a resin solution 3 having a double bond equivalent of 592 g / equivalent.
When various physical properties of the obtained resin solution 3 were measured, the weight average molecular weight was 8,100, the solid concentration obtained by drying at 160 ° C. under vacuum was 34.9%, and the solid content determined by the titration method The acid value per unit was 35 mgKOH / g. The Tg of the resin determined using DSC was −43.6 ° C.
(Example 1-4)
A separable flask with a cooling tube as a reaction vessel was charged with 566 parts of propylene glycol monomethyl ether (PGME), heated to 90 ° C. in a nitrogen atmosphere, and then added as a dropping system 1 with 15 parts of benzylmaleimide and 135 parts of acrylic acid. , 80 parts of cyclohexyl methacrylate (CHMA), 60 parts of M-5300 (manufactured by Toa Gosei Co., Ltd.), 40 parts of PGME, 6 parts of perbutyl O (trade name, polymerization initiator, manufactured by NOF Corporation), n-dropping system 3 6 parts of dodecyl mercaptan and 70 parts of PGME were each continuously fed over 3 hours. Then, after maintaining at 90 ° C. for 30 minutes, the temperature was raised to 115 ° C. and polymerization was continued for 1.5 hours.
Subsequently, 205 parts of glycidyl methacrylate, 250 parts of propylene glycol monomethyl ether (PGME), 1.5 parts of triethylamine as a catalyst, and 2,2′-methylenebis (4-methyl-6-t-butylphenol) as a polymerization inhibitor were added to this reaction liquid. (Product name “ANTAGE W400”, manufactured by Kawaguchi Chemical Industry Co., Ltd.) 0.8 parts are added, and the reaction is continued at 110 ° C. for 14 hours while bubbling nitrogen and oxygen mixed gas (oxygen concentration 7%). A resin solution 4 having a binding equivalent of 359 g / equivalent was obtained.
When various physical properties of the obtained resin solution 4 were measured, the weight average molecular weight was 15,700, the solid content concentration obtained by drying at 160 ° C. under vacuum was 32.3%, and the solid content determined by the titration method The per acid value was 87 mgKOH / g. The Tg of the resin determined using DSC was −7.5 ° C.
(Example 1-5)
In a separable flask equipped with a cooling tube as a reaction vessel, 504 parts of PGMEA were charged and heated to 90 ° C. under a nitrogen atmosphere. Then, 14 parts of benzylmaleimide, 33 parts of acrylic acid, and cyclohexyl methacrylate (CHMA) were added as the dropping system 1. 27 parts, 2-acryloyloxyethyl hexahydrophthalic acid (light acrylate HOA-HH manufactured by Kyoeisha Chemical Co., Ltd.) 200 parts, PGMEA 55 parts, perbutyl O (trade name, polymerization initiator, manufactured by NOF Corporation), 5 parts, As dripping system 3, 7 parts of n-dodecyl mercaptan and 80 parts of PGMEA were continuously supplied over 3 hours. Then, after maintaining at 90 ° C. for 30 minutes, the temperature was raised to 115 ° C. and polymerization was continued for 1.5 hours.
Subsequently, 87 parts of glycidyl methacrylate, 1.1 parts of triethylamine as a catalyst, 2,2′-methylenebis (4-methyl-6-tert-butylphenol) as a polymerization inhibitor (trade name “ANTAGE W400”, Kawaguchi, (Chemical Industry Co., Ltd.) 0.5 parts was added, and the reaction was continued at 110 ° C. for 12 hours while bubbling nitrogen and oxygen mixed gas (oxygen concentration: 7%), thereby causing a resin solution 5 having an equivalent of 589 g / double bond Got.
When various physical properties of the obtained resin solution 5 were measured, the weight average molecular weight was 12,000, the solid content obtained by drying at 160 ° C. under vacuum was 36.8%, and the solid content determined by the titration method The per acid value was 92 mgKOH / g. The Tg of the resin determined using DSC was −5.5 ° C.
(Comparative Example 1-1)
A separable flask with a cooling tube as a reaction vessel was charged with 485 parts of propylene glycol monomethyl ether (PGME) and heated to 90 ° C. in a nitrogen atmosphere. Then, 12 parts of benzylmaleimide and 200 parts of acrylic acid were added as the dropping system 1. , 44 parts of cyclohexyl methacrylate (CHMA), 45 parts of PGME, 4 parts of perbutyl O (trade name, polymerization initiator, manufactured by NOF Corporation), 18 parts of n-dodecyl mercaptan and 50 parts of PGME for 3 hours each as the dropping system 3 Continuously. Then, after maintaining at 90 ° C. for 30 minutes, the temperature was raised to 115 ° C. and polymerization was continued for 1.5 hours.
Subsequently, 319 parts of glycidyl methacrylate, 481 parts of PGME, 1.7 parts of triethylamine as a catalyst, and 2,2′-methylenebis (4-methyl-6-tert-butylphenol) as a polymerization inhibitor (trade name “ANTAGE W400”) 0.9 parts of Kawaguchi Chemical Co., Ltd.) was added, and the reaction was continued at 110 ° C. for 14 hours while bubbling nitrogen and oxygen mixed gas (oxygen concentration: 7%), so that the double bond equivalent of 267 g / equivalent A resin solution 6 was obtained.
When various physical properties of the obtained resin solution 6 were measured, the weight average molecular weight was 8,700, the solid content obtained by drying at 160 ° C. under vacuum was 34, 5%, and the solid content determined by the titration method. The per acid value was 66 mgKOH / g. The Tg of the resin determined using DSC was −8.5 ° C.
(Comparative Example 1-2)
In a separable flask with a cooling tube as a reaction tank, 602 parts of PGMEA and 258 parts of PGME were charged and heated to 90 ° C. in a nitrogen atmosphere, and then 80 parts of benzylmaleimide, 195 parts of acrylic acid, and PGMEA were added as the dropping system 1. 224 parts, 96 parts of PGM, 11 parts of perbutyl O (trade name, polymerization initiator, manufactured by NOF Corporation), 258 parts of vinyl toluene as dropping system 2, 16 parts of n-dodecyl mercaptan, 45 parts of PGMEA, 19 parts of PGME were continuously fed over 3 hours each. Then, after maintaining at 90 ° C. for 30 minutes, the temperature was raised to 115 ° C. and polymerization was continued for 1.5 hours.
Next, 263 parts of glycidyl methacrylate, 2.4 parts of triethylamine as a catalyst, and 1.2 parts of Antage W400 as a polymerization inhibitor were added to this reaction liquid, and 110% while bubbling nitrogen and oxygen mixed gas (oxygen concentration 7%). The resin solution 7 having a double bond equivalent of 432 g / equivalent was obtained by continuing the reaction at ° C for 14 hours.
When various physical properties of the obtained resin solution 7 were measured, the weight average molecular weight was 13,600, the solid concentration obtained by drying at 160 ° C. under vacuum was 35.7%, and the solid content determined by the titration method The per acid value was 80 mgKOH / g. The Tg of the resin determined using DSC was 22.8 ° C.
<Adjustment of photosensitive resin composition>
Photosensitive resin composition by mixing 2.5 parts of resin solution 1, 2.8 parts of PGMEA, 0.8 part of dipentaerythritol pentaacrylate, and 0.04 part of Irgacure 369 (manufactured by Ciba-Gaigi) as a photopolymerization initiator. 1 was obtained.
The photosensitive resin compositions 1-7 were obtained by said operation so that it might become 35% of solid content concentration about all the resin solutions 1-7.
<Evaluation of developability and surface smoothness of photosensitive resin composition>
(Example 2-1)
The obtained photosensitive resin composition 1 was spin-coated on a glass substrate and a PET film fixed on the glass substrate, and dried at 100 ° C. for 3 minutes to form a coating film.
The obtained coating film was exposed to 50 mJ / cm ² of UV light through a line-and-space photomask having a line width of 15 μm with a UV exposure apparatus (TME-150RNS manufactured by Topcon), and then the coating film was applied to 230 The film was heated at 30 ° C. for 30 minutes and tested for flexibility, developability of the negative resist, and residual film property.

Table 1 shows the amount of each component used in Examples 1-1 to 1-5 and Comparative Examples 1-1 to 1-2, and the analysis results of the obtained polymers.
The evaluation results in Examples 2-1 to 2-5 and Comparative Examples 2-1 to 2-2 are shown in Table 2.

Abbreviations in Tables 1 and 2 are as follows.
PGMEA: Propylene glycol monomethyl ether acetate PGME: Propylene glycol monomethyl ether BzMI: Benzylmaleimide AA: Acrylic acid BA: Butyl acrylate (butyl acrylate)
CHMA: cyclohexyl methacrylate (cyclohexyl methacrylate)
M-5300: Aronix (registered trademark) M-5300, ω-carboxy-polycaprolactone monoacrylate, manufactured by Toagosei Co., Ltd. HOAHH: Light acrylate HOA-HH, 2-acryloyloxyethyl hexahydrophthalic acid, manufactured by Kyoeisha Chemical Co., Ltd. PBO: perbutyl O, polymerization initiator, NOF Vt: vinyl toluene n-DM: n-dodecyl mercaptan GMA: glycidyl methacrylate (glycidyl methacrylate)
TEA: Triethylamine W400: Antage W400, trade name, 2,2′-methylenebis (4-methyl-6-tert-butylphenol, product manufactured by Kawaguchi Chemical Industry Co., Ltd. Mw: molecular weight of the finally obtained copolymer NV: solid Partial concentration AV: Acid value Tg: Glass transition temperature equivalent: Double bond equivalent

Claims (9)

A carboxyl group-containing radically polymerizable copolymer synthesized using a monomer containing (meth) acrylates and unsaturated imides , wherein the carboxyl group is separated from the main chain by 7 or more elements. is arranged, and having a structure of the following structure units (a1) and / or (a2), further have a radical polymerizable double bond in a side chain, a glass transition temperature of -50 ° C. or higher, at 0 ℃ below carboxyl group-containing radical polymerizable copolymer, characterized in that.

(In the formula, R ₁ represents hydrogen or a methyl group. R ₂ represents a divalent organic group having 5 to 10 carbon atoms, and may or may not have a substituent. R ₅ represents an alkylene group, which may or may not have a substituent, and R ₆ represents a divalent organic group having 2 to 10 carbon atoms and has a substituent. (It may or may not have. N represents an integer of 1 to 5.) 2. The carboxyl group-containing radical polymerizable copolymer according to claim 1, wherein the double bond equivalent is 359 to 2000 g / equivalent. The carboxyl group-containing radical-polymerizable copolymers, the following component units (b1) and / or (b2) according to claim 1 or 2, wherein the carboxyl group-containing radical polymerizable co characterized by having a structure of Polymer.

(In the formula, R ₁ , R ₂ , R ₅ , R ₆ and n represent the same meaning as in the above general formulas (a1) and (a2). R ₃ can react with a carboxyl group in the molecule. (A divalent group derived from a monomer having a functional group and a radical polymerizable double bond, R ₄ represents hydrogen or a methyl group.) Functional groups capable of reacting with the previous SL carboxyl group, a glycidyl group, oxazolinyl group, carboxyl group-containing radical polymerizable copolycondensates according to claim 3 is at least one selected from the group consisting of isocyanate group and an oxetanyl group Coalescence. Carboxyl group-containing radical polymerizable copolymer according to claim 1 acid value of the carboxyl group-containing radical polymerizable copolymer is characterized by a 30 to 150 mg KOH / g. The carboxyl group-containing radical polymerizable copolymer is a polymer obtained by reacting a cyclic lactone with a copolymer obtained by copolymerizing (meth) acrylic acid, or a copolymer obtained by copolymerizing a hydroxyl group-containing (meth) acrylic acid. The carboxyl group-containing radical polymerizable copolymer according to claim 1, which is a polymer obtained by reacting an acid anhydride with a carboxyl group-containing radical polymerizable copolymer. The said carboxyl group-containing radically polymerizable copolymer is a polymer obtained by reacting a monomer having a glycidyl group and a (meth) acryloyl group, according to any one of claims 1 to 6. Carboxyl group-containing radical polymerizable copolymer. A carboxyl group-containing radical polymerizable copolymer according to any one of claims 1 to 7 and a photopolymerization initiator, for a color filter photosensitive resin composition which comprises a colorant. A color filter comprising a colored pattern using the photosensitive resin composition for a color filter according to claim 8 .