JP7179649B2 - A radically polymerizable polymer and a resin composition containing the radically polymerizable polymer - Google Patents

Description

The present invention relates to a radically polymerizable polymer soluble in an alkaline aqueous solution and a resin composition containing the radically polymerizable polymer. More specifically, it relates to a cured product using it.

Photosensitive resin compositions for image formation can be microfabricated by applying the principle of photography (photolithography), and can form images by giving cured products with excellent physical properties. It is widely used for applications such as various resist materials and printing plates. In recent years, from the standpoint of environmental measures, the alkali developing type, which can be developed with a dilute weakly alkaline aqueous solution, has become mainstream.
When a negative-type photosensitive resin composition for image formation is used in a photographic process (photolithography), the resin composition is first applied onto a substrate and then dried by heating to form a coating film. After that, a series of steps of mounting a pattern forming film on the coating film, exposing it to light, and developing it are adopted. Coating films after photocuring are required to have properties related to long-term reliability such as heat resistance, water resistance, and moisture resistance in addition to developability.

As a material that satisfies the above characteristics to some extent, a carboxyl group-containing vinyl ester obtained by reacting an acid anhydride with a vinyl ester (epoxy acrylate) obtained by reacting an epoxy resin and (meth)acrylic acid to introduce a carboxyl group is known. It is This carboxyl group-containing vinyl ester satisfies conflicting properties such as tack-free property, photosensitivity, and developability in a well-balanced manner. However, there is a need for further improvement and compatibility.

For this purpose, for example, an unsaturated group-containing polycarboxylic acid obtained by reacting a (meth)acrylate compound having two carboxyl groups in the molecule with an epoxy resin having two epoxy groups in the molecule A resin composition containing an acid resin is known to have good important properties such as developability, heat resistance, and flexibility (see Patent Document 1). However, with the progress of technology, higher-level properties are required, for example, high dimensional stability suitable for fine pattern formation and resistance to processing under higher temperature conditions are required. It has become so.

By the way, polymers having an N-substituted maleimide group and an ethylenically unsaturated double bond have been studied as photosensitive resins that can meet the demand for high heat resistance (for example, Patent Documents 2 and 3). However, even in these systems, if too much emphasis is placed on heat resistance, the alkali developability may decrease or the cured product may become brittle. There is room for improvement in terms of the balance of Furthermore, when it is used as a coating film, it has been required to have good adhesion to the substrate.

JP-A-2001-48945 JP-A-10-139843 JP-A-2002-62651

Therefore, the object of the present invention is to provide a cured product having excellent alkali solubility and curability without exhibiting brittleness and having excellent adhesion to the substrate when used as a coating film. An object of the present invention is to provide a polymer and a resin composition containing the same.

As a result of intensive studies, the present inventors have found that a specific resin has alkali solubility and curability, does not exhibit brittleness, and when used as a coating film, a cured product with excellent adhesion to the substrate. I have found what I can give.
That is, the objects of the present invention are achieved by the following (1) to (8).
(1) In 100% by mass of the polymer, 20 to 60% by mass of structural units derived from maleimide monomers, 28 to 50% by mass of structural units derived from unsaturated carboxylic acid monomers having no ester bond, hydroxyl groups Containing 1 to 19% by mass of structural units derived from a monomer having, and 5 to 35% by mass of structural units derived from an aromatic monomer having no ester bond as essential units, the hydroxyl group in 1 g of the polymer 0.1×10 ⁻³ to 1.4×10 ⁻³ mol of the carboxyl groups of the polymer are reacted with a monomer having a functional group capable of reacting with the carboxyl groups. The radically polymerizable polymer has 1.8×10 ⁻³ to 3.3×10 ⁻³ moles of hydroxyl groups per 1 g of the radically polymerizable polymer.
(2) The radically polymerizable polymer according to (1), wherein the structural unit derived from the unsaturated carboxylic acid monomer having no ester bond is a structural unit derived from (meth)acrylic acid.
(3) A resin composition comprising the radically polymerizable polymer according to (1) or (2) and a radically polymerizable compound.
(4) A cured product obtained by curing the radically polymerizable polymer described in (1) or (2) or the resin composition described in (3).
(5) In 100% by mass of the monomer component, 20 to 60% by mass of a maleimide-based monomer, 28 to 50% by mass of an unsaturated carboxylic acid monomer having no ester bond, and 1 to 50% by mass of a monomer having a hydroxyl group 19% by mass and 5 to 35% by mass of an aromatic monomer having no ester bond are reacted so that the hydroxyl group in 1 g is 0.1 × 10 ^-3 to Step (I) to obtain a polymer that is 1.4×10 ⁻³ mol;
A monomer having a functional group capable of reacting with the carboxyl group is reacted with the carboxyl group of the polymer so that the hydroxyl group in 1 g is 1.8×10 ⁻³ to 3.3×10 ⁻³ a step (II) of obtaining a radically polymerizable polymer that is molar;
A method for producing a radically polymerizable polymer comprising
(6) The method for producing a radically polymerizable polymer according to (5), wherein in the step (I), the polymer is obtained by polymerization in a mixed solvent of esters and alcohols.

The radically polymerizable polymer of the present invention and the resin composition containing it have good alkali solubility and curability, and the obtained cured product does not exhibit brittleness. It is excellent for

The radically polymerizable polymer of the present invention includes structural units derived from a maleimide monomer, structural units derived from an unsaturated carboxylic acid monomer having no ester bond, structural units derived from a monomer having a hydroxyl group, and A monomer having a functional group capable of reacting with a carboxyl group is reacted with a carboxyl group of a polymer (base polymer) having a structural unit derived from an aromatic monomer having no ester bond as an essential unit. It has a structure consisting of The carboxyl group is contained in a structural unit derived from the unsaturated carboxylic acid monomer having no ester bond in the polymer (base polymer). In the radically polymerizable polymer of the present invention, a functional group capable of reacting with a carboxyl group is added to, preferably part of, the carboxyl group of the structural unit derived from the unsaturated carboxylic acid monomer having no ester bond. It has a structure obtained by adding a monomer having
In the radically polymerizable polymer, the constituent units derived from the polymer (base polymer) constitute the main chain. The structural unit derived from the monomer having a functional group capable of reacting with the carboxyl group constitutes the side chain of the radically polymerizable polymer.

The monomer having a functional group capable of reacting with a carboxyl group preferably has a radically polymerizable carbon-carbon double bond (hereinafter sometimes simply referred to as a radically polymerizable double bond).
The radically polymerizable polymer of the present invention is preferably composed of 20 to 60% by mass of structural units derived from a maleimide monomer in 100% by mass of the main chain, and an unsaturated carboxylic acid monomer having no ester bond. Containing 28 to 50% by mass of structural units, 1 to 19% by mass of structural units derived from a monomer having a hydroxyl group, and 5 to 35% by mass of structural units derived from an aromatic monomer having no ester bond, and , has a radically polymerizable carbon-carbon double bond in the side chain.
In the following, the description of a monomer unit indicates a structural unit derived from a monomer, and the polymerizable carbon-carbon double bond (C=C) in the monomer is a single bond (C- C). For example, a maleimide-based monomer unit means a constitutional unit derived from a maleimide-based monomer when the maleimide-based monomer is copolymerized or graft-polymerized.

A polymer (base polymer) having maleimide-based monomer units, unsaturated carboxylic acid (monomer) units having no ester bonds, and aromatic monomers having no ester bonds as essential units is maleimide. It is preferably obtained by radically polymerizing a system monomer, an unsaturated carboxylic acid having no ester bond, and an aromatic monomer having no ester bond as essential components. The monomer will be explained below.

Maleimide monomers include N-phenylmaleimide, N-(2-methylphenyl)maleimide, N-(4-methylphenyl)maleimide, N-(2,6-diethylphenyl)maleimide, N-(2- chlorophenyl)maleimide, N-methylmaleimide, N-ethylmaleimide, N-isopropylmaleimide, N-laurylmaleimide, N-cyclohexylmaleimide, N-benzylmaleimide, N-phenylmethylmaleimide, N-(2,4,6-tri Bromophenyl)maleimide, N-[3-(triethoxysilyl)propyl]maleimide, N-octadecenylmaleimide, N-dodecenylmaleimide, N-(2-methoxyphenyl)maleimide, N-(2, 4,6-trichlorophenyl)maleimide, N-(4-hydroxyphenyl)maleimide, N-(1-hydroxyphenyl)maleimide and other N-substituted maleimides and unsubstituted maleimides, and one or more of these can be used in combination. Among these, N-phenylmaleimide, N-(2-methylphenyl)maleimide, and N-(2,6-diethylphenyl) are highly effective in improving heat resistance, have good copolymerizability, and are readily available. Maleimide, N-laurylmaleimide, N-cyclohexylmaleimide, N-benzylmaleimide and the like are preferred, N-phenylmaleimide, N-cyclohexylmaleimide and N-benzylmaleimide are more preferred, and N-phenylmaleimide and N-benzylmaleimide are most preferred. .
It is also preferable to use N-phenylmaleimide and N-benzylmaleimide together. A preferred ratio of N-phenylmaleimide and N-benzylmaleimide when used in combination is 99:1 to 1:99 by weight.

In addition, in the present invention, an unsaturated carboxylic acid having no ester bond is used as a monomer as an essential component in order to introduce a carboxyl group that is essential for alkali development and to improve the properties of the cured product. . Specific examples thereof include (meth)acrylic acid, crotonic acid, cinnamic acid, sorbic acid, fumaric acid, maleic acid, etc. Among them, (meth)acrylic acid is preferred because of its excellent cured product properties. Moreover, as another aspect, other acid groups may be introduced together with the carboxyl groups or instead of the carboxyl groups. Other acid groups include, for example, phenolic hydroxyl groups, carboxylic acid anhydride groups, phosphoric acid groups, sulfonic acid groups, and other functional groups that undergo a neutralization reaction with alkaline water. or two or more types. In the following description, the description for the carboxyl group also applies to the other acid groups mentioned above.

In the present invention, a monomer having a hydroxyl group (hydroxyl group) is used as an essential component. Conventionally, a polymer obtained by copolymerizing (meth)acrylic acid is known as a polymer having a carboxyl group, but there is room for improvement in terms of alkali developability. and the hydroxyl group in the hydroxyl group-containing skeleton is reacted with a polybasic acid anhydride, or as described in Patent Document 3, glycidyl in the glycidyl group-containing skeleton It is known that the group is reacted with an unsaturated monobasic acid such as (meth)acrylic acid, and the hydroxyl group formed by ring-opening the glycidyl group is reacted with a polybasic acid anhydride. However, there is still room for improvement in both alkali developability and heat resistance.

On the other hand, in the present invention, good alkali developability can be expressed by copolymerizing both an unsaturated carboxylic acid having no ester bond and a monomer having a hydroxyl group as essential components. The properties of the cured product can also be excellent. Examples of monomers having a hydroxyl group in the molecule include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, and 2-hydroxy(meth)acrylate. (di)hydroxyalkyl (meth)acrylates such as butyl, 3-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 2,3-dihydroxypropyl (meth)acrylate, and 2-hydroxymethyl (meth)acrylamide, 2-hydroxyethyl (meth)acrylamide, 2-hydroxypropyl (meth)acrylamide, 3-hydroxypropyl (meth)acrylamide, 4-hydroxybutyl (meth)acrylamide, hydroxypivalyl (meth)acrylamide, 5 hydroxyalkyl (meth)acrylamides such as -hydroxypentyl (meth)acrylamide and 6-hydroxyhexyl (meth)acrylamide, and one or more of these can be used. Among them, hydroxyalkyl (meth)acrylates are preferred from the viewpoint of copolymerizability, and 2-hydroxyethyl (meth)acrylate is particularly preferred.

In the present invention, an aromatic monomer having no ester bond is used as an essential component because of good copolymerizability with the maleimide monomer and excellent properties of the cured product. Specific examples include styrene, α-methylstyrene, α-chlorostyrene, vinyltoluene, and the like, and styrene is most preferred from the viewpoint of excellent electrical properties and low cost.

The maleimide-based monomer (maleimide-based monomer unit) accounts for 20 to 60% by mass of the total monomer components (100% by mass of all monomer units). By setting the content of the maleimide-based monomer to 20% by mass or more, sufficient heat resistance can be imparted to the cured product. On the other hand, by setting the content to 60% by mass or less, it is possible to sufficiently impart alkali developability and cured product properties resulting from the unsaturated carboxylic acid, the monomer having a hydroxyl group, and the aromatic monomer. . A preferable lower limit of the maleimide-based monomer is 25% by mass, and a more preferable lower limit is 30% by mass. A preferred upper limit is 55% by mass, and a more preferred upper limit is 50% by mass.

Unsaturated carboxylic acid having no ester bond (unsaturated carboxylic acid unit having no ester bond) accounts for 28 to 50% by mass of all monomer components (100% by mass of all monomer units). By setting the unsaturated carboxylic acid content to 28% by mass or more, good alkali developability can be exhibited. On the other hand, by setting the content to 50% by mass or less, it is possible to sufficiently impart cured product properties such as heat resistance resulting from the maleimide-based monomer and the aromatic-based monomer. A preferable lower limit of the unsaturated carboxylic acid is 29% by mass, and a more preferable lower limit is 30% by mass. A preferred upper limit is 48% by mass, and a more preferred upper limit is 45% by mass.

A monomer having a hydroxyl group (a monomer unit having a hydroxyl group) is 1 to 19% by mass in the total monomer components constituting the polymer (100% by mass of the total monomer units constituting the polymer). be. By setting the content of the monomer having a hydroxyl group to 1% by mass or more, good solubility in a solvent and good alkali developability can be exhibited. On the other hand, by setting the content to 19% by mass or less, it is possible to sufficiently impart cured product properties such as heat resistance due to the maleimide monomer. A more preferable lower limit of the hydroxyl group-containing monomer is 2% by mass, and a further preferable lower limit is 3% by mass. A more preferable upper limit is 18% by mass, and a still more preferable upper limit is 17% by mass.

Aromatic monomers having no ester bond (aromatic monomer units having no ester bond) are 5 to 35% by mass of all monomer components (total monomer units 100% by mass) is. By setting the content of the aromatic monomer to 5% by mass or more, sufficient properties of the cured product can be imparted. On the other hand, when the content is 35% by mass or less, sufficient heat resistance and alkali developability due to the maleimide monomer, the unsaturated carboxylic acid, and the hydroxyl group-containing monomer can be imparted. A preferable lower limit of the aromatic monomer content is 7% by mass, and a more preferable lower limit is 10% by mass. A preferred upper limit is 33% by mass, and a more preferred upper limit is 30% by mass.

In the radically polymerizable polymer and the resin composition containing the radically polymerizable polymer of the present invention, the hydroxyl group per gram of the polymer (base polymer) is 1.4×10 ⁻³ mol or less. By setting the upper limit of the hydroxyl group in 1 g of the polymer as described above, the alkali developability of the radical polymerizable polymer of the present invention and the resin composition containing the radical polymerizable polymer, physical properties of the cured coating (especially (adhesion to the substrate) can be made excellent. A preferable upper limit of the hydroxyl group is 1.3×10 ⁻³ mol, and a more preferable upper limit is 1.2×10 ⁻³ mol.
Moreover, the number of hydroxyl groups in 1 g of the polymer (base polymer) is 0.1×10 ⁻³ mol or more. By setting the lower limit of hydroxyl groups in 1 g of the polymer as above, the solubility in a solvent and the alkali developability of the radically polymerizable polymer of the present invention and the resin composition containing the radically polymerizable polymer are improved. can be excellent. A more preferable lower limit is 0.2×10 ⁻³ mol, and a further preferable lower limit is 0.3×10 ⁻³ mol.
The number of hydroxyl groups in 1 g of the polymer can be calculated by dividing the number of moles of the hydroxyl-containing monomer used in synthesizing the polymer by the mass of the obtained polymer. Alternatively, it may be determined by a known method for measuring a hydroxyl value.

In the present invention, other copolymerizable monomer components may be used in obtaining the polymer (base polymer) as long as the properties are not adversely affected.
Specific examples of such monomer components include vinyl ester monomers such as vinyl acetate and vinyl adipate; (meth)acrylic monomers such as methyl (meth)acrylate, ethyl (meth)acrylate and butyl (meth)acrylate; Alkyl vinyl ethers such as n-propyl vinyl ether, isopropyl vinyl ether, n-butyl vinyl ether, isobutyl vinyl ether, n-hexyl vinyl ether, cyclohexyl vinyl ether, and 2-ethylhexyl vinyl ether, and corresponding alkyl vinyl (thio) ethers such as maleic anhydride. Acid anhydride group-containing monomers or monomers obtained by ring-opening modification of acid anhydride groups with alcohols or the like, and unsaturated basic acids other than those described above; N such as N-vinylpyrrolidone and N-vinyloxazolidone -Vinyl monomers; cyano group-containing monomers such as acrylonitrile and methacrylonitrile;

The content of the above-mentioned other copolymerizable monomer components is the total of all monomer components constituting the base polymer (100 mass% of all monomer units constituting the base polymer), preferably 30% by mass, more preferably 0 to 20% by mass, still more preferably 0 to 10% by mass.

In the method for producing a radically polymerizable polymer of the present invention, 20 to 60% by mass of a maleimide-based monomer and 28 to 50% by mass of an unsaturated carboxylic acid monomer having no ester bond in 100% by mass of the monomer component. %, 1 to 19% by mass of a monomer having a hydroxyl group, and 5 to 35% by mass of an aromatic monomer having no ester bond are reacted to react the above monomer components, a step (I) of obtaining a polymer having hydroxyl groups of 0.1×10 ⁻³ to 1.4×10 ⁻³ mol; and a functional group capable of reacting with the carboxyl group of the carboxyl group of the polymer. and a step (II) of ^reacting a ^monomer having .

In the step (I) of reacting the monomer components to obtain a polymer (base polymer), the method of obtaining the polymer is not particularly limited, and a conventionally known polymerization method such as a solution polymerization method or a bulk polymerization method is employed. is possible. Among them, the solution polymerization method is preferable because the temperature control during the polymerization reaction is easy.

The solvent for solution polymerization is not particularly limited as long as it does not inhibit polymerization or degrade each component of the raw material monomers. Specific examples of usable solvents include hydrocarbons such as toluene and xylene; (di)ethylene glycol monoethyl ether acetate, (di) propylene glycol monomethyl ether acetate, (di)methyl glutarate, and (di)succinate. esters such as methyl, (dimethyl)adipate, methyl acetate, ethyl acetate, butyl acetate, methyl propionate; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone; diethyl ether, diisopropyl ether, tetrahydrofuran, 1,4 - ethers such as dioxane, methyl-t-butyl ether, (di)ethylene glycol dimethyl ether; amides such as N,N-dimethylacetamide; sulfoxides such as dimethylsulfoxide; can be mixed and used. In particular, when the amount of maleimide-based monomer used exceeds 30% by mass or when the amount of unsaturated carboxylic acid such as (meth)acrylic acid used exceeds 30% by mass, monomers and polymers In order to improve the solubility of , a mixed solvent of an ester such as diethylene glycol monoethyl ether acetate or propylene glycol monomethyl ether acetate and an alcohol such as propylene glycol monomethyl ether, isopropanol or isobutanol is preferred.

Polymerization initiators that can be used in the polymerization reaction include ordinary radical polymerization initiators. Specifically, 2,2′-azobisisobutyronitrile, 2,2′-azobis(4-methoxy-2,4-dimethylvaleronitrile), 2,2′-azobis(2,4-dimethylvaleronitrile ), azo compounds such as 2,2′-azobis (2-methylisobutyronitrile); lauroyl peroxide, benzoyl peroxide, t-butyl peroxyneodecanate, t-butyl peroxypivalate, t- Organic peroxides such as amyl peroxyoctoate, t-butyl peroxy-2-ethylhexanoate, t-butyl peroxybenzoate, methyl ethyl ketone peroxide, and dicumyl peroxide can be used, and the desired reaction It may be appropriately selected and used according to the conditions and the properties required for the polymer to be obtained.

The amount of the polymerization initiator used is preferably 0.001 to 15% by mass, more preferably 0.01 to 10% by mass, based on 100% by mass of the monomer component used in the polymerization reaction. be.

A specific method for obtaining a polymer (base polymer) is not particularly limited, but a method in which all components are charged in a solvent at once and polymerized, a reaction vessel in which a solvent and a part of the components are charged in advance, and the remaining components are added. can be employed, for example, a method of continuously adding or sequentially adding to polymerize.

In the production of the polymer (base polymer), 20 to 60% by mass of maleimide-based monomers and 28 to 50% by mass of unsaturated carboxylic acid monomers having no ester bonds in the total monomer components constituting the base polymer. %, a monomer having a hydroxyl group, a monomer having 5 to 35% by mass of an aromatic monomer having no ester bond as an essential component, using the polymerization initiator, it is preferable to radically polymerize. .

The pressure during the reaction is not particularly limited, and the reaction may be carried out under normal pressure or pressurized conditions. The temperature during the polymerization reaction depends on the type and composition ratio of the raw material monomers used and the type of solvent used, but is usually preferably in the range of 20 to 150°C, more preferably 30 to 120°C. .

At the time of the polymerization reaction, it is preferable to set the amounts of the solvent and each monomer component so that the final solid content concentration of the polymer solution is 10 to 70% by mass. If the final solid content concentration is less than 10% by mass, the productivity is lowered, which is not preferable. On the other hand, if the final solid content exceeds 70% by mass, the polymerization conversion rate may not increase even in the case of solution polymerization due to an increase in the viscosity of the polymerization solution. More preferably, the final solids concentration is 20-65% by mass, more preferably 25-60% by mass.

Considering the properties of the radically polymerizable polymer of the present invention and the resin composition containing the radically polymerizable polymer, the alkali developability, the physical properties of the cured coating film, the heat resistance, etc., the weight average molecular weight Mw of the polymer is preferably 1,000 to 100,000 in terms of polystyrene as a value measured by gel permeation chromatography (GPC). By setting Mw to 1,000 or more, sufficient heat resistance can be imparted to the cured product. On the other hand, by setting Mw to 100,000 or less, sufficient alkali developability can be imparted. A more preferable lower limit of Mw is 2,000, and a further preferable lower limit is 3,000. A more preferable upper limit is 50,000, and a further preferable upper limit is 30,000.
If necessary, a chain transfer agent may be used during the polymerization reaction in order to adjust the molecular weight within this range.

Any chain transfer agent may be used as long as it does not adversely affect each monomer component used in the polymerization, and thiol compounds are usually used. Specifically, alkyl mercaptans such as n-octyl mercaptan, n-dodecyl mercaptan and t-dodecyl mercaptan; aryl mercaptans such as thiophenol; mercapto group-containing aliphatic carboxylic acids such as mercaptopropionic acid and methyl mercaptopropionate; Esters and the like are preferred. The amount of the chain transfer agent to be used is not particularly limited, and may be appropriately adjusted so as to obtain a polymer having a desired molecular weight. .1 to 15% by mass, more preferably 0.5 to 10% by mass.

Next, in the step (II) of obtaining a radically polymerizable polymer, a monomer having a functional group capable of reacting with a carboxyl group is reacted with the carboxyl group of the polymer (base polymer) to obtain a radically polymerizable polymer. to obtain a radically polymerizable polymer. In order to impart radical polymerizability, a radical polymerizable carbon-carbon double bond introduction reaction is preferably carried out. The radically polymerizable group (preferably carbon-carbon double bond) introduction reaction involves introducing a carboxyl group of the polymer, a functional group capable of reacting with the carboxyl group, and a radically polymerizable group (preferably a carbon-carbon double bond). It is a reaction with the above functional group of the monomer having, a polymerization inhibitor such as methylhydroquinone or oxygen, a tertiary amine such as triethylamine, a quaternary ammonium salt such as triethylbenzylammonium chloride, 2-ethyl-4-methyl The reaction can be carried out at about 80 to 130° C. in the coexistence of reaction catalysts such as imidazoles such as imidazole, phosphorus compounds such as triphenylphosphine, organic and inorganic acid salts of metals, and chelate compounds. In another embodiment, the carboxyl group may be reacted with the above other acid group together with or instead of the carboxyl group.

The functional group capable of reacting with a carboxyl group is preferably selected from the group consisting of a glycidyl group, an oxazolinyl group, an isocyanate group and an oxetanyl group, and the radically polymerizable carbon-carbon double bond is a (meth)acryloyl group. is preferred.

Specific examples of monomers having a glycidyl group include glycidyl (meth) acrylate, allyl glycidyl ether, α-ethylglycidyl (meth) acrylate, 3,4-epoxycyclohexylmethyl acrylate (for example, " Cychromer A400”, etc.), 3,4-epoxycyclohexylmethyl methacrylate (eg, “Cychromer M100” manufactured by Daicel Chemical Industries, Ltd.), and the like.

Specific examples of monomers having an oxazolinyl group include N-vinyloxazoline, 2-isopropenyl-2-oxazoline and the like.

Specific examples of the isocyanate group-containing monomer include (meth)acryloyloxyethyl isocyanate, (meth)acryloyloxyethoxyethyl isocyanate, bis(acryloxymethyl)ethyl isocyanate, modified products thereof, and the like. More specifically, "Karenzu MOI" (methacryloyloxyethyl isocyanate), "Karenzu AOI" (acryloyloxyethoxyethyl isocyanate), "Karenzu MOI-EG" (methacryloyloxyethoxyethyl isocyanate), "Karenzu MOI-BM" ( Karenz MOI isocyanate-blocked), Karenz MOIBP (isocyanate-blocked Karenz MOI), and Karenz BEI (bis(acryloxymethyl)ethyl isocyanate) are commercially available from Showa Denko. All of these product names are registered trademarks.

Specific examples of monomers having an oxetanyl group include 3-(meth)acryloyloxymethyloxetane and 3-ethyl-3-(meth)acryloyloxymethyloxetane.

One or more of these monomers can be used. Among these, a glycidyl group and an oxetanyl group, which generate a hydroxyl group by reaction with a carboxyl group, are preferable in order to obtain 1.8×10 ⁻³ to 3.3×10 ⁻³ mol of hydroxyl groups in 1 g of the radically polymerizable polymer. From the viewpoint of reactivity and industrial availability, glycidyl (meth)acrylate and 3,4-epoxycyclohexylmethyl methacrylate are more preferred. Particularly preferred are glycidyl methacrylate and 3,4-epoxycyclohexylmethyl methacrylate. Furthermore, glycidyl (meth)acrylate is more preferable because it is easy to set the amount of hydroxyl groups in a desired range with a low addition amount. By making it a low addition amount, it does not impair the characteristics of the main chain (base polymer) skeleton, has excellent alkali solubility and curability, does not express brittleness, and when it is used as a coating film, it is compatible with the substrate. It is possible to more easily provide a radically polymerizable polymer capable of giving a cured product with excellent adhesion and a resin composition containing the same.

The amount of the monomer having a functional group capable of reacting with a carboxyl group is preferably 10 to 50 parts by mass, more preferably 20 to 50 parts by mass, based on 100 parts by mass of the polymer (base polymer). By adjusting the amount of the monomer having a functional group capable of reacting with a carboxyl group, the amount of hydroxyl groups in 1 g of the radically polymerizable polymer can be easily controlled to a predetermined value.

In the radically polymerizable polymer of the present invention, the radically polymerizable carbon-carbon double bond introduction reaction is preferably carried out so that the double bond equivalent is 300 to 4000 g/equivalent. The double bond equivalent is related to photocurability and physical properties of the cured product, and by setting it within the above range, a cured product having excellent physical properties such as heat resistance, strength and flexibility can be obtained. Also, a well-balanced photosensitive resin is obtained in which photocurability and alkali developability are compatible. A more preferred range of double bond equivalent weight is 350 to 3000 g/equivalent, more preferably 400 to 2500 g/equivalent.

In the radically polymerizable polymer and the resin composition comprising the radically polymerizable polymer of the present invention, the number of hydroxyl groups in 1 g of the radically polymerizable polymer is 3.3×10 ⁻³ mol or less. By setting the upper limit of hydroxyl groups in 1 g of the radically polymerizable polymer as above, the alkali developability and physical properties of the cured coating film of the radically polymerizable polymer of the present invention and the resin composition containing the radically polymerizable polymer are improved. (Particularly, adhesion to the base material) can be made excellent. A preferable upper limit of the hydroxyl group is 3.2×10 ⁻³ mol, and a more preferable upper limit is 3.1×10 ⁻³ mol.
Moreover, the number of hydroxyl groups in 1 g of the radically polymerizable polymer is 1.8×10 ⁻³ mol or more. By setting the lower limit of hydroxyl groups in 1 g of the radically polymerizable polymer as above, the solubility of the radically polymerizable polymer of the present invention and the resin composition comprising the radically polymerizable polymer in a solvent, the alkali development, and the It is possible to improve the properties. A more preferable lower limit is 1.85×10 ⁻³ mol, and a further preferable lower limit is 1.9×10 ⁻³ mol.
The hydroxyl groups in 1 g of the radically polymerizable polymer can react with the number of moles of the monomer having a hydroxyl group used in synthesizing the polymer and the carboxyl group used in synthesizing the radically polymerizable polymer. It can be calculated by dividing the sum of the number of moles of the functional group-containing monomer and the mass of the resulting radically polymerizable polymer. Moreover, it may be obtained by a known method for measuring the hydroxyl value of the radically polymerizable polymer.

The acid value of the radically polymerizable polymer is preferably 30 mgKOH/g or more, more preferably 40 mgKOH/g or more, still more preferably 50 mgKOH/g or more, and preferably 160 mgKOH/g or less, more preferably 155 mgKOH/g or less, and 150 mgKOH. /g or less is more preferable. By setting the acid value of the radically polymerizable polymer to 30 mgKOH/g or more, it becomes easier to express good alkali developability. When the acid value of the radically polymerizable polymer is 160 mgKOH/g or less, the exposed portion is less likely to be eroded by the alkaline developer, and the water resistance and humidity resistance of the cured product are improved.

The amount of the monomer having a functional group capable of reacting with a carboxyl group to be used is 0.01 to 0.99 per equivalent of the carboxyl group of the polymer before the radically polymerizable carbon-carbon double bond introduction reaction. It is preferable to determine the double bond equivalent and the acid value of the obtained radically polymerizable polymer within the range of equivalents so as to fall within the above preferred ranges. The preferred range of Mw of the radically polymerizable polymer of the present invention is the same as the preferred range of Mw of the polymer before the radically polymerizable carbon-carbon double bond introduction reaction.

In the radically polymerizable polymer of the present invention, the relative value X/Y between the post-heat treatment residual ratio X (mass%) and the solid content concentration Y (mass%) obtained by the following formula is preferably 0.9 or more. .
Residual rate after heat treatment X (mass%) = {mass (g )}/{mass of radically polymerizable polymer before heat drying 0.3 (g)}
Solid content concentration Y (% by mass) = {Mass (g) of solid content obtained by heating and drying 0.3 g of the radically polymerizable polymer (mass before heat drying) at 160°C for 1 hour and 30 minutes under vacuum}/ {Mass of radically polymerizable polymer before heat drying 0.3 (g)}

In the above formula, the radically polymerizable polymer may contain the above solvent. Heat drying of the radically polymerizable polymer is preferably carried out in a container with high thermal conductivity such as an aluminum cup. As for the mass of 0.3 g of the radically polymerizable polymer before heat drying, it is sufficient if the accurately weighed mass is known, and it may be around 0.3 g (for example, 0.28 to 0.32 g).

In the radically polymerizable polymer of the present invention, 20 to 60% by mass of structural units derived from maleimide monomers in 100% by mass of structural units derived from all monomers in the polymer before radically polymerizable group introduction reaction, ester 28 to 50% by mass of structural units derived from unsaturated carboxylic acid monomers having no bonds, 1 to 19% by mass of structural units derived from monomers having hydroxyl groups, aromatic monomers having no ester bonds Since 5 to 35% by mass of the derived structural unit is contained as an essential unit, the ester bond content can be kept low, and excellent thermal decomposition resistance can be obtained.

The relative value X/Y becomes 1 when no thermal decomposition occurs, and the closer the relative value X/Y is to 1, the better the thermal decomposition resistance. The relative value X/Y is preferably 0.91 or more, more preferably 0.92 or more, and still more preferably 0.94 or more.

Since the radically polymerizable polymer of the present invention has both a carboxyl group and a radically polymerizable group (preferably a radically polymerizable carbon-carbon double bond), it can be used alone as an alkali-soluble photosensitive resin. can also In particular, it can be suitably used as a negative alkali-soluble photosensitive resin.

In the present invention, a resin composition containing a radically polymerizable polymer and a known radically polymerizable compound is used to obtain a coating film having a crosslinked structure through heat or photoreaction. Such radically polymerizable compounds include radically polymerizable resins and radically polymerizable monomers.

Unsaturated polyesters, epoxy acrylates, urethane acrylates, polyester acrylates, and the like can be used as radically polymerizable resins. When these radically polymerizable resins are used, it is preferable to use the radically polymerizable resin in an amount of 80% by mass or less based on 100% by mass of the radically polymerizable polymer of the present invention. A more preferable upper limit is 70% by mass, and an even more preferable upper limit is 60% by mass.

As the radically polymerizable monomer, both monofunctional monomers (having one radically polymerizable double bond) and polyfunctional monomers (having two or more radically polymerizable double bonds) can be used. Since the radically polymerizable monomer participates in polymerization, it can improve the properties of the resulting cured product and also adjust the viscosity of the resin composition. When the radically polymerizable monomer is used, the preferred usage amount is 300% by mass or less, more preferably 100% by mass or less, relative to 100% by mass of the radically polymerizable polymer of the present invention. A preferable lower limit is 1% by mass, more preferably 5% by mass, based on 100% by mass of the radically polymerizable polymer.

Specific examples of radically polymerizable monomers include N-phenylmaleimide, N-(2-methylphenyl)maleimide, N-(4-methylphenyl)maleimide, N-(2,6-diethylphenyl)maleimide, N-( 2-chlorophenyl)maleimide, N-methylmaleimide, N-ethylmaleimide, N-isopropylmaleimide, N-laurylmaleimide, N-cyclohexylmaleimide, N-phenylmethylmaleimide, N-(2,4,6-tribromophenyl) Maleimide, N-[3-(triethoxysilyl)propyl]maleimide, N-octadecenylmaleimide, N-dodecenylmaleimide, N-(2-methoxyphenyl)maleimide, N-(2,4,6) N-substituted maleimide group-containing monomers such as -trichlorophenyl)maleimide, N-(4-hydroxyphenyl)maleimide, N-(1-hydroxyphenyl)maleimide; styrene, α-methylstyrene, α-chlorostyrene, vinyl aromatic vinyl monomers such as toluene, p-hydroxystyrene, divinylbenzene, diallyl phthalate, and diallylbenzene phosphonate; vinyl ester monomers such as vinyl acetate and vinyl adipate; (meth)acrylic acid, methyl (meth)acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 4- Hydroxymethyl (meth)acrylamide, pentaerythritol mono (meth) acrylate, dipentaerythritol mono (meth) acrylate, trimethylolpropane mono (meth) acrylate, 1,6-hexanediol mono (meth) acrylate, glycerol mono (meth) Acrylates, (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[2-(meth)acryloyloxyethyl]triazine, dendritic acrylate and other (meth)acrylic monomers; n-propyl vinyl ether, isopropyl vinyl ether, n-butyl vinyl (Hydroxy) alkyl vinyl (thio) ethers such as nyl ether, isobutyl vinyl ether, n-hexyl vinyl ether, cyclohexyl vinyl ether, 2-ethylhexyl vinyl ether, 4-hydroxybutyl vinyl ether; 2-(vinyloxyethoxy) ethyl (meth)acrylate, ( 2-(isopropenoxyethoxyethoxy)ethyl meth)acrylate, 2-(isopropenoxyethoxyethoxyethoxy)ethyl (meth)acrylate, 2-(isopropenoxyethoxyethoxyethoxyethoxy)ethyl (meth)acrylate, etc. vinyl (thio) ether having a radically polymerizable double bond; maleic anhydride group-containing monomers, or monomers obtained by ring-opening the acid anhydride group with alcohols, amines, water, etc. monomers; N-vinyl monomers such as N-vinylpyrrolidone and N-vinyloxazolidone; and compounds having at least one radically polymerizable double bond such as allyl alcohol and triallyl cyanurate.
These are appropriately selected according to the intended use and required properties, and can be used singly or in combination of two or more.

The resin composition containing the radically polymerizable polymer and the radically polymerizable compound of the present invention can be thermally polymerized by using a known thermal polymerization initiator such as benzoyl peroxide and cumene hydroperoxide. However, radical polymerization by light becomes possible by using a photosensitive resin composition containing a photopolymerization initiator. In particular, it can be a negative photosensitive resin composition.

Known photopolymerization initiators can be used, and benzoin such as benzoin, benzoin methyl ether, benzoin ethyl ether and alkyl ethers thereof; acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 1,1-dichloroacetophenone; , 4-(1-t-butyldioxy-1-methylethyl)acetophenone and other acetophenones; 2-methylanthraquinone, 2-amylanthraquinone, 2-t-butylanthraquinone, 1-chloroanthraquinone and other anthraquinones; 2,4 -thioxanthones such as dimethylthioxanthone, 2,4-diisopropylthioxanthone, and 2-chlorothioxanthone; ketals such as acetophenone dimethyl ketal and benzyl dimethyl ketal; Benzophenones such as 3,3′,4,4′-tetrakis(t-butyldioxycarbonyl)benzophenone; 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-propan-1-one and 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1; acylphosphine oxides and xanthones;

These photopolymerization initiators are used alone or as a mixture of two or more, and are contained in an amount of 0.5 to 30% by mass based on 100% by mass of the total amount of the radically polymerizable polymer and the radically polymerizable compound of the present invention. preferably. When the amount of the photopolymerization initiator is less than 0.5% by mass, it is necessary to increase the light irradiation time, or polymerization is difficult to occur even if light irradiation is performed, so an appropriate surface hardness cannot be obtained. Gone. Even if the amount of the photopolymerization initiator exceeds 30% by mass, there is little merit in using a large amount.

The resin composition of the present invention may further contain fillers such as talc, clay and barium sulfate, coloring pigments, antifoaming agents, coupling agents, leveling agents, sensitizers, releasing agents and lubricants, if necessary. , plasticizers, antioxidants, ultraviolet absorbers, flame retardants, polymerization inhibitors, thickeners, and other known additives may be added. Moreover, various reinforcing fibers can be used as reinforcing fibers to form a fiber-reinforced composite material.

When the resin composition comprising the radically polymerizable polymer and the radically polymerizable compound of the present invention is used for image formation, it is usually applied to a substrate by a known method, dried and exposed to light for curing. After the coating film is obtained, the unexposed portion is dissolved in an alkaline aqueous solution to carry out alkali development.

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. , trimethylamine, monoethylamine, diethylamine, triethylamine, monopropylamine, dimethylpropylamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrabutylammonium hydroxide, monoethanolamine, diethanolamine, triethanolamine, ethylenediamine, diethylenetriamine, dimethyl Water-soluble organic amines such as aminoethyl methacrylate and polyethyleneimine can be mentioned, and one or more of these can be used.

The resin composition of the present invention can also be used in the form of a dry film obtained by coating a film such as polyethylene terephthalate in advance and drying it, in addition to the method of applying the liquid composition directly to the substrate. In this case, a dry film may be laminated on the substrate and the film peeled off before or after exposure.
In addition, the CTP (Computer To Plate) system, which has been widely used in the field of printing platemaking recently, does not use a pattern forming film during exposure, and scans and exposes the coating film directly with laser light according to digitized data. can be adopted.

Hereinafter, the present invention will be described in more detail with reference to examples, but the following examples do not limit the present invention, and all modifications and implementations without departing from the spirit of the present invention are included in the technical scope of the present invention. be done. In each example, parts and percentages are based on mass unless otherwise specified. In the following examples, physical properties were evaluated as follows.

In the following examples, various physical properties were measured as follows.

<Acid value>
About 0.3 g of each solution obtained in the following Synthesis Examples 1 to 5 was precisely weighed, dissolved in an acetone / water mixed solvent, and a 0.1 N KOH aqueous solution was used as a titrant. Co., Ltd.) was used to measure the acid value. Table 1 shows the results.

<Heat decomposition resistance>
About 0.3 g of each of the solutions obtained in Synthesis Examples 1 to 5 below was placed in an aluminum cup, weighed accurately, added with about 2 ml of acetone, mixed well, and placed in a hot air dryer at 200°C. The mass after drying by heating for 30 minutes was measured, and the mass after drying by heating at 200° C. was divided by the mass before drying by heating to obtain the post-heating residual ratio X (%). The relative value (X/Y) between this X (%) and the solid content concentration Y (%) obtained by drying by heating at 160° C. for 1 hour and 30 minutes under vacuum was evaluated. The larger this value, the higher the thermal decomposition resistance. Table 1 shows the results.

<Alkali solubility>
A solution obtained with the formulation shown in Table 2 was applied onto a copper plate by spin coating, dried at 80°C for 30 minutes, cooled to room temperature, and immersed in a 1% by mass sodium carbonate aqueous solution at 30°C for 10 seconds. It was evaluated by the solubility of the coating film. Table 2 shows the results. A case where no undissolved coating film was visually observed was evaluated as ◯, and a case where undissolved undissolved film was observed was evaluated as X.

<Photocurability>
After irradiating the test plate for alkali solubility evaluation obtained above with light of 2 J/cm ² , evaluation was performed by immersing it in a 1 mass % sodium carbonate aqueous solution at 30° C. for 10 seconds. Table 2 shows the results. A case where no dissolution of the coating film was visually observed was evaluated as ◯, and a case where dissolution was observed was evaluated as x.

<Adhesion>
The cured product after the photocurability evaluation was heated at 150° C. for 30 minutes as a high temperature condition. After cooling to room temperature, the state of the coating film after being immersed in a 1% by mass sodium carbonate aqueous solution at 30° C. for 5 minutes was evaluated. Table 2 shows the results. A case where peeling or lifting of the coating film was not visually observed was rated as ◯, and a case where peeling or lifting of the coating film was observed was rated as X.

Synthesis example 1
Synthesis of Radically Polymerizable Polymer 117.8 g of isobutanol was introduced into a separable flask equipped with a cooling tube as a reaction tank, stirred while replacing with nitrogen, and heated to 100°C. Next, N-phenylmaleimide (molecular weight 173.17) 40 g, acrylic acid (molecular weight 72.06) 35 g, styrene (molecular weight 104.15) 10 g, 2-hydroxyethyl methacrylate (molecular weight 130.14) 15 g, diethylene glycol 120 g of monoethyl ether acetate, 62.2 g of isobutanol, and 6 g of Perbutyl O (t-butylperoxy-2-ethylhexanoate, manufactured by NOF Corporation) were mixed to prepare a dropping composition. While maintaining the reaction temperature at 100° C., this composition was added dropwise over 3 hours. After the completion of dropping, the reaction was continued at 100° C. for 30 minutes. After that, the reaction temperature was raised to 115° C. while distilling off isobutanol, and the reaction was continued for 1.5 hours to obtain a polymer solution before radical polymerizable double bond introduction reaction. The number of hydroxyl groups in 1 g of the polymer was calculated by dividing the number of moles of 2-hydroxyethyl methacrylate by the mass of the polymer as follows.
15/130.14÷(40+35+10+15)=1.15×10 ⁻³ mol

Then, to this polymer solution, 29.6 g of BLEMMER GS (trade name; manufactured by NOF Corporation, glycidyl methacrylate, molecular weight: 142.15), 0.13 g of triphenylphosphine as a reaction catalyst, and Antage W- as a polymerization inhibitor. 0.19 g of 400 was added and reacted at 115° C. while bubbling a mixed gas of nitrogen and oxygen (oxygen concentration 7%). After completion of the reaction, diethylene glycol monoethyl ether acetate was added so that the solid content concentration was about 50% to obtain a radically polymerizable polymer solution A-1 of the example. The number of hydroxyl groups in 1 g of the radically polymerizable polymer was calculated by dividing the sum of the number of moles of 2-hydroxyethyl methacrylate and the number of moles of glycidyl methacrylate by the mass of the radically polymerizable polymer.
(15/130.14+29.6/142.15)/(40+35+10+15+29.6)
= 2.50 × 10 ^-3 mol

When various physical properties were measured for the obtained radically polymerizable polymer solution A-1, the solid content concentration obtained by heating and drying at 160° C. under vacuum was 49.6%, and the acid value per solid content was 131 mgKOH. /g. The thermal decomposition resistance was X/Y=0.95.

Synthesis Examples 2-5
In the same manner as in Synthesis Example 1, except that the amount of each monomer used in Synthesis Example 1 was changed to the amount shown in Table 1, the radically polymerizable polymer solutions A-2 and A-3 of Examples and Comparative Examples were prepared. Radical polymerizable polymer solutions B-1 and B-2 were obtained. Table 1 shows the results of measurement of these various physical properties.

Examples 1-3, Comparative Examples 1-2
Using each of the solutions obtained in Synthesis Examples 1 to 5 above, formulations shown in Table 2 were prepared, and alkali solubility, photocurability, and TCT resistance were evaluated by the methods described above. The results are shown in Table 2 together.

The terms in Table 2 are as follows.
Monomer: dipentaerythritol hexaacrylate Polymerization initiator: Irgacure 907 (photopolymerization initiator manufactured by BASF Japan)

The thermal decomposition resistance was good, being 0.95 or higher in all cases. Further, as shown in Examples 1 to 3, the resin compositions obtained using the radically polymerizable polymer solutions A-1 to A-3 had good alkali solubility, photocurability, and adhesion. there were.
On the other hand, as shown in Comparative Examples 1 and 2, the resin composition using the comparative radically polymerizable polymer solution B-1 has poor adhesion, and the resin composition using the comparative radically polymerizable polymer solution B-2 The composition was poor in alkali solubility.
Since the radically polymerizable polymer of the present invention and the resin composition comprising the radically polymerizable polymer and the radically polymerizable compound have alkali-solubility essential for microfabrication, the photosensitive resin It can be used as a composition.

The radically polymerizable polymer of the present invention and the resin composition comprising the radically polymerizable polymer and the radically polymerizable compound have excellent heat resistance, alkali solubility, and photocurability, Furthermore, when it is made into a cured coating film, it has good adhesion to the object to be coated, so it is used as a constituent component of a photosensitive resin composition for forming an image that can be developed with an alkali, for example, a protective film for printing plates and a color filter. , color filters, black matrices, photo spacers, black column spacers, quantum dots, organic EL, micro LEDs, mini LEDs, and other displays.

Claims (6)

In 100% by mass of the polymer, 20 to 60% by mass of structural units derived from a maleimide monomer, 28 to 50% by mass of structural units derived from an unsaturated carboxylic acid monomer having no ester bond, and a monomer having a hydroxyl group 1 to 19% by mass of a structural unit derived from a polymer and 5 to 35% by mass of a structural unit derived from an aromatic monomer having no ester bond as essential units. A radical having a structure obtained by reacting a monomer having a functional group capable of reacting with a carboxyl group of 1×10 ⁻³ to 1.4×10 ⁻³ mol of the polymer. A radically polymerizable polymer having hydroxyl groups of 1.8×10 ⁻³ to 3.3×10 ⁻³ mol per gram of the radically polymerizable polymer. 2. The radically polymerizable polymer according to claim 1, wherein the structural unit derived from the unsaturated carboxylic acid monomer having no ester bond is a structural unit derived from (meth)acrylic acid. A resin composition comprising the radically polymerizable polymer according to claim 1 or 2 and a radically polymerizable compound. A cured product obtained by curing the radically polymerizable polymer according to claim 1 or 2 or the resin composition according to claim 3. 20 to 60% by mass of maleimide-based monomers, 28 to 50% by mass of unsaturated carboxylic acid monomers having no ester bonds, and 1 to 19% by mass of monomers having hydroxyl groups in 100% by mass of monomer components , and the monomer component essentially containing 5 to 35% by mass of an aromatic monomer having no ester bond is reacted so that the hydroxyl group in 1 g is 0.1 × 10 ^-3 to 1.4 a step (I) of obtaining a polymer that is ×10 ⁻³ moles;
A monomer having a functional group capable of reacting with the carboxyl group is reacted with the carboxyl group of the polymer so that the hydroxyl group in 1 g is 1.8×10 ⁻³ to 3.3×10 ⁻³ a step (II) of obtaining a radically polymerizable polymer that is molar;
A method for producing a radically polymerizable polymer comprising 6. The method for producing a radically polymerizable polymer according to claim 5, wherein in the step (I), the polymer is obtained by polymerization in a mixed solvent of esters and alcohols.