JP2023004059A - Radical-polymerizable polymer and photosensitive composition thereof - Google Patents

Abstract

To provide a radical-polymerizable polymer from which a cured product having good handleability and excellent coating workability, and excellent transparency and adhesion can be imparted, and a photosensitive resin composition containing the radical-polymerizable polymer.SOLUTION: A radical-polymerizable polymer has an acid group and an ethylenically unsaturated double bond in a side chain, wherein the radical-polymerizable polymer has a structural unit having a ring structure in a main chain and a structural unit represented by general formula (1), has a double bond equivalent of 330-1,600 (g/eq.) and a weight average molecular weight of 14,000 or less, a content ratio of the structural unit represented by general formula (2) is 5 mass% or less with respect to 100 mass% of the total structural units of the radical-polymerizable polymer, and the acid group has an interval between the main chain and the acid group of 6 or less atoms. A photosensitive resin composition contains the radical-polymerizable polymer, a polyfunctional monomer, a polymerization initiator, inorganic fine particles, and a solvent.SELECTED DRAWING: None

Description

The present invention relates to radically polymerizable polymers and photosensitive compositions thereof. More particularly, it relates to a radically polymerizable polymer and a photosensitive resin composition containing a radically polymerizable polymer, a polyfunctional monomer, a photopolymerization initiator, inorganic fine particles and a solvent.

Curable resin compositions that can be cured by heat or active energy rays are used in various applications such as color filters, inks, printing plates, printed wiring boards, semiconductor elements, and photoresists used in liquid crystal display devices, solid-state imaging devices, and the like. Various applications have been studied for various applications such as optical members and electrical and electronic equipment, and curable resin compositions having excellent properties required for each application have been developed. As a photosensitive resin composition excellent in heat resistance and adhesion, for example, Patent Document 1 describes a photosensitive resin composition for color filters containing a carboxyl group-containing radically polymerizable copolymer. contains a monomer unit derived from an N-substituted maleimide compound, and has a carboxyl group and an ethylenically unsaturated double bond, and the copolymer has a Tg (glass transition temperature) of 20° C. or less. A resin composition is described.
Further, as a polymer capable of giving a cured product having excellent solvent resistance, for example, Patent Document 2 discloses a structural unit derived from an N-substituted maleimide compound and a hydrocarbon group having a carbon number within a specific range. It has a structural unit, has a double bond equivalent weight of 330 to 2000 g/equivalent, has a glass transition temperature of less than 50 ° C., and the content ratio of the structural unit having an aromatic group is 100% by mass of the total structural units. It describes a radically polymerizable copolymer having an acid group content of 5% by mass or less and having a distance of 6 atoms or less between the acid group in the side chain and the main chain.

As described above, the level of various properties required for optical materials is increasing, and there is a demand for polymers and photosensitive resin compositions thereof that are excellent in transparency and handleability.

JP 2012-32772 A JP 2019-163359 A

In view of the above-mentioned current situation, the present invention includes a radically polymerizable polymer that is easy to handle, has excellent coating workability, and can give a cured product having excellent transparency and adhesion, and the radically polymerizable polymer. An object of the present invention is to provide a photosensitive resin composition.

In order to solve the above problems, the present inventors have made various studies on polymers that can be used for optical members and electric and electronic equipment applications. is a radically polymerizable polymer having a side chain, wherein the radically polymerizable polymer has a structural unit having a ring structure in the main chain and a specific structural unit, and has a double bond equivalent and a weight average molecular weight of a specific By using a copolymer in which the content ratio of other specific structural units is within a specific range, and the position of the acid group is within a specific range, excellent coating workability, excellent transparency and adhesion It was found that a cured product can be obtained. In addition, the present inventors have found that a photosensitive resin composition containing such a radically polymerizable polymer is particularly suitable as a resin composition for forming optical members such as color filters. was completed.
That is, the present invention provides a radically polymerizable polymer having an acid group and an ethylenically unsaturated double bond in a side chain, the radically polymerizable polymer comprising a structural unit having a ring structure in its main chain, and It has a structural unit represented by the following general formula (1), has a double bond equivalent of 330 to 1600 (g/equivalent), has a weight average molecular weight of 14000 or less, and is represented by the following general formula (2). is 5% by mass or less with respect to 100% by mass of the total structural units of the radically polymerizable polymer, and the acid group has a distance of 6 atoms or less from the main chain. It is a radically polymerizable polymer characterized by:

（式中、Ｒ^１は、水素原子又はメチル基を表す。Ｒ^２は、炭素数６～２０の直鎖状又は分岐状の炭化水素基を表す。）

(In the formula, R ¹ represents a hydrogen atom or a methyl group. R ² represents a linear or branched hydrocarbon group having 6 to 20 carbon atoms.)

（式中、Ｒ^３は、水素原子又はメチル基を表す。）
上記ラジカル重合性重合体は、酸価が５０～１５０（ｍｇＫＯＨ／ｇ）であることが好ましい。
上記ラジカル重合性重合体は、上記一般式（１）で表される構造単位の含有割合が、上記ラジカル重合性重合体の全構造単位１００質量％に対して１０質量％以上であることが好ましい。
上記酸基は、（メタ）アクリル酸由来のカルボキシル基であることが好ましい。
上記ラジカル重合性重合体は、ガラス転移温度が５０℃以下であることが好ましい。
本発明はまた、上述のラジカル重合性重合体、及び多官能モノマーを含むことを特徴とする感光性樹脂組成物でもある。
上記感光性樹脂組成物は、更に光重合開始剤、無機微粒子及び溶剤を含むことが好ましい。

( ^In the formula, R3 represents a hydrogen atom or a methyl group.)
The radical polymerizable polymer preferably has an acid value of 50 to 150 (mgKOH/g).
In the radically polymerizable polymer, the content ratio of the structural unit represented by the general formula (1) is preferably 10% by mass or more with respect to 100% by mass of the total structural units of the radically polymerizable polymer. .
The acid group is preferably a carboxyl group derived from (meth)acrylic acid.
The radically polymerizable polymer preferably has a glass transition temperature of 50° C. or lower.
The present invention is also a photosensitive resin composition characterized by containing the above radically polymerizable polymer and a polyfunctional monomer.
The photosensitive resin composition preferably further contains a photopolymerization initiator, inorganic fine particles and a solvent.

The radically polymerizable polymer and the photosensitive resin composition of the present invention are easy to handle, excellent in coating workability, and can give a cured product excellent in transparency and adhesion. Such a radically polymerizable polymer and photosensitive resin composition of the present invention can be used for optical applications such as color filters, inks, printing plates, printed wiring boards, semiconductor elements and photoresists used in liquid crystal display devices, solid-state imaging devices and the like. It can be suitably used for various uses such as members, electric and electronic devices.

The present invention will be described in detail below.
In addition, the form which combined two or more of each preferable form of this invention described below is also a preferable form of this invention.
Moreover, in this specification, "(meth)acrylic acid" means "acrylic acid and/or methacrylic acid", and "(meth)acrylate" means "acrylate and/or methacrylate".
Further, in this specification, the numerical range "Min to Max" means the minimum value Min or more and the maximum value Max or less. Furthermore, when describing preferred numerical values in stages for the upper and lower limits, a numerical range obtained by appropriately combining the upper and lower limits that are separately described is also a preferred numerical range.
1. Radically polymerizable polymer The radically polymerizable polymer of the present invention is a radically polymerizable polymer having an acid group and an ethylenically unsaturated double bond in the side chain, and the radically polymerizable polymer has having a structural unit having a ring structure and a structural unit represented by the following general formula (1), having a double bond equivalent of 330 to 1600 (g/equivalent), and having a weight average molecular weight of 14000 or less, The content ratio of the structural unit represented by the following general formula (2) is 5% by mass or less with respect to 100% by mass of the total structural units of the radically polymerizable polymer, and the acid group is spaced from the main chain is a radically polymerizable polymer characterized by having 6 or less atoms.

（式中、Ｒ^１は、水素原子又はメチル基を表す。Ｒ^２は、炭素数６～２０の直鎖状又は分岐状の炭化水素基を表す。）

(In the formula, R ¹ represents a hydrogen atom or a methyl group. R ² represents a linear or branched hydrocarbon group having 6 to 20 carbon atoms.)

（式中、Ｒ^３は、水素原子又はメチル基を表す。）
本発明のラジカル重合性重合体は、上記構成からなるため、取り扱い性が良く塗布作業性に優れ、透明性及び密着性に優れた硬化物を与えることができる。
本発明のラジカル重合性重合体が上述のように優れるのは、特定範囲の物性パラメーターを満たし、主鎖に環構造を有する構造単位を有することと、上記一般式（１）で表される構造単位を含むことと、酸基が特定範囲の位置にあることによると推測される。
本発明のラジカル重合性重合体は、酸基及びエチレン性不飽和二重結合を側鎖に有する。
上記ラジカル重合性重合体が酸基を側鎖に有することにより、アルカリ可溶性となり、現像性を発揮することができる。また、上記ラジカル重合性重合体の硬化物において、密着性を発揮することができる。
上記酸基は、主鎖との間隔が原子数６以下である。上記酸基が特定範囲の位置にあることにより、上記ラジカル重合性重合体の現像性を向上させる。また、上記ラジカル重合性重合体に含まれる一般式（１）構造単位の炭化水素基の炭素数が６～２０であることとの組み合わせにより後述する無機微粒子の分散性が良好となり得る。
通常、主鎖から比較的遠く離れた位置に酸基を有するラジカル重合性重合体を製造する場合、ビニル系単量体に酸基を有する化合物又は酸無水物を反応させてビニル基から離れた位置に酸基を有する単量体を合成し、この単量体を用いて共重合を行う。例えば、ヒドロキシエチル（メタ）アクリレートと無水マレイン酸とを反応させることでビニル基から離れた位置に酸基を有する単量体を得ることができるが、この単量体を共重合させて製造されたラジカル重合性重合体をカラーフィルターの製造に用いると、後硬化工程（加熱工程）時に、水が付加してマレイン酸部分が脱離し、これが異物となって、得られる硬化物の耐熱性や透明性等を低下させる場合がある。これに対し、酸基と主鎖との間隔が原子数６以下である場合、ビニル系単量体に酸基を有する化合物又は酸無水物を反応させた単量体を使用する必要がないため、カラーフィルターの製造工程で酸基部分が脱離するようなことがなく、ラジカル重合性重合体の耐熱性や透明性等が低下することがない。
ここで、本発明において、主鎖との間隔が原子数６以下であるとは、側鎖が結合した主鎖の原子と、側鎖上で酸基が結合した原子との間の原子数が６以下であることをいう。例えば、下記（ａ１）で表される構造単位においては、酸基Ｘは、主鎖との間隔が原子数４であるとし、下記（ａ２）で表される構造単位においては、酸基Ｘは、主鎖との間隔が原子数６であるとする。また、酸基が主鎖に直接結合している場合は、主鎖との間隔が原子数０であるとする。

( ^In the formula, R3 represents a hydrogen atom or a methyl group.)
Since the radically polymerizable polymer of the present invention has the above constitution, it is easy to handle, excellent in coating workability, and can give a cured product excellent in transparency and adhesion.
The radically polymerizable polymer of the present invention is excellent as described above because it satisfies a specific range of physical property parameters and has a structural unit having a ring structure in the main chain, and the structure represented by the general formula (1) It is speculated that this is due to the inclusion of units and the specific range of positions of the acid groups.
The radically polymerizable polymer of the present invention has an acid group and an ethylenically unsaturated double bond in its side chain.
By having an acid group in the side chain of the radically polymerizable polymer, it becomes alkali-soluble and can exhibit developability. In addition, the cured product of the radically polymerizable polymer can exhibit adhesion.
The number of atoms between the acid group and the main chain is 6 or less. The position of the acid group within the specific range improves the developability of the radically polymerizable polymer. In combination with the fact that the hydrocarbon group of the structural unit of general formula (1) contained in the radically polymerizable polymer has 6 to 20 carbon atoms, the dispersibility of the inorganic fine particles described later can be improved.
Usually, when producing a radically polymerizable polymer having an acid group at a position relatively far away from the main chain, a compound or an acid anhydride having an acid group is reacted with a vinyl monomer to remove the acid group from the vinyl group. A monomer having an acid group at the position is synthesized and copolymerized using this monomer. For example, by reacting hydroxyethyl (meth)acrylate and maleic anhydride, it is possible to obtain a monomer having an acid group at a position distant from the vinyl group, and the copolymer is produced by copolymerizing this monomer. When the radically polymerizable polymer is used in the production of a color filter, water is added during the post-curing process (heating process), and the maleic acid moiety is eliminated. It may reduce transparency and the like. On the other hand, when the distance between the acid group and the main chain is 6 atoms or less, there is no need to use a compound having an acid group or a monomer obtained by reacting an acid anhydride with a vinyl monomer. , the acid group portion is not eliminated during the production process of the color filter, and the heat resistance, transparency, etc. of the radically polymerizable polymer are not deteriorated.
Here, in the present invention, the fact that the number of atoms between the main chain is 6 or less means that the number of atoms between the atom of the main chain to which the side chain is bonded and the atom to which the acid group is bonded on the side chain is 6 or less. For example, in the structural unit represented by (a1) below, the acid group X has a distance of 4 atoms from the main chain, and in the structural unit represented by (a2) below, the acid group X is , and the distance from the main chain is 6 atoms. Also, when the acid group is directly bonded to the main chain, the distance between the acid group and the main chain is assumed to be 0 atoms.

上記酸基は、主鎖との間隔が原子数６以下であることが好ましく、５以下であることがより好ましく、０であることが更に好ましい。
上記酸基は、主鎖に直接結合していることが好ましい。
上記酸基としては、例えば、カルボキシル基、フェノール性水酸基、カルボン酸無水物基、リン酸基、スルホン酸基等、アルカリ水と中和反応する官能基が挙げられる。中でも、カルボキシル基又はカルボン酸無水物基が好ましく、より好ましくはカルボキシル基であり、更に好ましくは（メタ）アクリル酸基である。現像速度をより高める観点から、アクリル酸基の方が好ましい。
また、上記ラジカル重合性共重合体は、側鎖にエチレン性不飽和二重結合を有する。これにより、熱、光架橋反応が可能になるため、硬化性、現像密着性や耐溶剤性等が向上する。また、光に対する感度が向上し、より少ない光で硬化し、かつ硬化後の硬化物の機械的強度も向上させることができる。
本発明において、上記エチレン性不飽和二重結合とは、重合性二重結合、すなわち炭素－炭素二重結合を意味する。
上記エチレン性不飽和二重結合としては、例えば、（メタ）アクリロイル基、ビニル基、アリル基、メタリル基等が挙げられる。本発明のラジカル重合性重合体は、これらの１種又は２種以上を有していてもよい。なかでも、反応性の点で、（メタ）アクリロイル基であることが好ましい。
上記エチレン性不飽和二重結合は、例えば、エポキシ基含有単量体（Ｘ）を上記ラジカル重合性重合体の製造時に用いることで、上記ラジカル重合性重合体に導入することができる。
上記エポキシ基含有単量体（Ｘ）としては、エポキシ基と、重合性二重結合とを含む化合物が挙げられる。重合性二重結合としては、例えば、上述したエチレン性不飽和二重結合と同様であり、（メタ）アクリロイル基、ビニル基、アリル基、メタリル基等が挙げられ、これらの１種又は２種以上を有するものが好適である。なかでも、反応性の点で（メタ）アクリロイル基が好ましい。
本明細書中、エポキシ基には、狭義のエポキシ基の他、グリシジル基のようにオキシラン環が炭素に結合している基や、グリシジルエーテル基及びグリシジルエステル基のようにエーテル結合又はエステル結合を含む基、エポキシシクロヘキサン環等が含まれるものとする。
上記エポキシ基含有単量体（Ｘ）としては、例えば、（メタ）アクリル酸グリシジル、（メタ）アクリル酸β－メチルグリシジル、（メタ）アクリル酸β－エチルグリシジル、ビニルベンジルグリシジルエーテル、アリルグリシジルエーテル、（メタ）アクリル酸（３，４－エポキシシクロヘキシル）メチル、ビニルシクロヘキセンオキシド等が挙げられる。なかでも、反応性が高く、かつ反応のコントロールがしやすいうえ、入手が容易で、ラジカル重合性二重結合だけでなく同時に水酸基も導入できる点から、（メタ）アクリル酸グリシジル、及び／又は、（メタ）アクリル酸３，４－エポキシシクロヘキシルメチルがより好ましい。更に好ましくは（メタ）アクリル酸グリシジル（別名：グリシジル（メタ）アクリレート）であり、特に好ましくはメタクリル酸グリシジルである。
本発明のラジカル重合性重合体は、主鎖に環構造を有する構造単位、及び、上記一般式（１）で表される構造単位を有する。各構造単位について説明する。
（主鎖に環構造を有する構造単位）
上記ラジカル重合性重合体は、主鎖に環構造を有する構造単位（以下、「構造単位（Ａ）」とも称する。）を有する。
主鎖骨格に環構造を有する構造単位を有することにより、本発明のラジカル重合性重合体の耐熱性が向上し、また、硬化物の密着性や耐溶剤性を向上させることができる。
上記構造単位（Ａ）を与える単量体としては、分子内に二重結合含有環構造を有する単量体や、環化重合して環構造を主鎖に有する重合体を形成する単量体等の１種又は２種以上が好適である。このような単量体としては、Ｎ置換マレイミド系単量体、ジアルキル－２，２’－（オキシジメチレン）ジアクリレート系単量体、及び、α－（不飽和アルコキシアルキル）アクリレートからなる群より選択される少なくとも１種を用いることが好適である。このように主鎖に環構造を有する構造単位は、Ｎ―置換マレイミド系単量体単位、ジアルキル－２，２’－（オキシジメチレン）ジアクリレート系単量体単位、及び／又は、α－（不飽和アルコキシアルキル）アクリレート系単量体単位が好適である。
特にＮ―置換マレイミド系単量体単位、及び／又は、ジアルキル－２，２’－（オキシジメチレン）ジアクリレート系単量体単位を含む重合体は、耐熱性や分散性（例えば、色材や無機微粒子の分散性）、硬度等がより向上された硬化物を与えることが可能になる。
上述の単量体単位を含む重合体とは、例えば、単量体の重合反応や架橋反応によって当該単量体由来の構成単位を含む重合体を意味する。
上記単量体成分において、Ｎ置換マレイミド系単量体としては、例えば、Ｎ－シクロヘキシルマレイミド、Ｎ－フェニルマレイミド、Ｎ－メチルマレイミド、Ｎ－エチルマレイミド、Ｎ－イソプロピルマレイミド、Ｎ－ｔ－ブチルマレイミド、Ｎ－ドデシルマレイミド、Ｎ－ベンジルマレイミド、Ｎ－ナフチルマレイミド等が挙げられ、これらの１種又は２種以上を用いることができる。中でも、着色の少なさや分散性に優れる点で、Ｎ－シクロヘキシルマレイミド、Ｎ－フェニルマレイミド、Ｎ－ベンジルマレイミドが好ましく、特にＮ－ベンジルマレイミドとＮ－フェニルマレイミドが好適である。
上記Ｎ－ベンジルマレイミドとしては、例えば、ベンジルマレイミド；ｐ－メチルベンジルマレイミド、ｐ－ブチルベンジルマレイミド等のアルキル置換ベンジルマレイミド；ｐ－ヒドロキシベンジルマレイミド等のフェノール性水酸基置換ベンジルマレイミド；ｏ－クロロベンジルマレイミド、ｏ－ジクロロベンジルマレイミド、ｐ－ジクロロベンジルマレイミド等のハロゲン置換ベンジルマレイミド等が挙げられる。
上記Ｎ－フェニルマレイミドとしては、例えば、フェニルマレイミド；ｐ－メチルフェニルマレイミド、ｐ－ブチルフェニルマレイミド等のアルキル置換フェニルマレイミド；ｐ－ヒドロキシフェニルマレイミド等のフェノール性水酸基置換フェニルマレイミド；ｏ－クロロフェニルマレイミド、ｏ－ジクロロフェニルマレイミド、ｐ－ジクロロフェニルマレイミド等のハロゲン置換フェニルマレイミド等が挙げられる。
上記ジアルキル－２，２’－（オキシジメチレン）ジアクリレート系単量体としては、着色の少なさや分散性、工業的入手の容易さ等の観点から、例えば、ジメチル－２，２’－［オキシビス（メチレン）］ビス－２－プロペノエート等を用いることが好適である。
上記α－（不飽和アルコキシアルキル）アクリレートとしては、例えば、α－アリルオキシメチルアクリル酸、α－アリルオキシメチルアクリル酸メチル、α－アリルオキシメチルアクリル酸エチル、α－アリルオキシメチルアクリル酸ｎ－プロピル、α－アリルオキシメチルアクリル酸ｉ－プロピル、α－アリルオキシメチルアクリル酸ｎ－ブチル、α－アリルオキシメチルアクリル酸ｓ－ブチル、α－アリルオキシメチルアクリル酸ｔ－ブチル、α－アリルオキシメチルアクリル酸ｎ－アミル、α－アリルオキシメチルアクリル酸ｓ－アミル、α－アリルオキシメチルアクリル酸ｔ－アミル、α－アリルオキシメチルアクリル酸ネオペンチル、α－アリルオキシメチルアクリル酸ｎ－ヘキシル、α－アリルオキシメチルアクリル酸ｓ－ヘキシル、α－アリルオキシメチルアクリル酸ｎ－ヘプチル、α－アリルオキシメチルアクリル酸ｎ－オクチル、α－アリルオキシメチルアクリル酸ｓ－オクチル、α－アリルオキシメチルアクリル酸ｔ－オクチル、α－アリルオキシメチルアクリル酸２－エチルヘキシル、α－アリルオキシメチルアクリル酸カプリル、α－アリルオキシメチルアクリル酸ノニル、α－アリルオキシメチルアクリル酸デシル、α－アリルオキシメチルアクリル酸ウンデシル、α－アリルオキシメチルアクリル酸ラウリル、α－アリルオキシメチルアクリル酸トリデシル、α－アリルオキシメチルアクリル酸ミリスチル、α－アリルオキシメチルアクリル酸ペンタデシル、α－アリルオキシメチルアクリル酸セチル、α－アリルオキシメチルアクリル酸ヘプタデシル、α－アリルオキシメチルアクリル酸ステアリル、α－アリルオキシメチルアクリル酸ノナデシル、α－アリルオキシメチルアクリル酸エイコシル、α－アリルオキシメチルアクリル酸セリル、α－アリルオキシメチルアクリル酸メリシル等の鎖状飽和炭化水素基含有α－（アリルオキシメチル）アクリレートが好ましい。その他、アルキル－（α－メタリルオキシメチル）アクリレート系単量体等も好ましい。中でも、α－アリルオキシメチルアクリル酸メチル（α－（アリルオキシメチル）メチルアクリレートとも称す）が特に好適である。
上記α－（不飽和アルコキシアルキル）アクリレートは、例えば、国際公開第２０１０／１１４０７７号パンフレットに開示されている製造方法により製造することができる。
上記ラジカル重合性重合体は、上記構造単位（Ａ）として、１種のみを有していてもよいし、２種以上有していてもよい。
上記構造単位（Ａ）の含有割合は、上記ラジカル重合性重合体の現像性、透明性、及び密着性の両立を考慮すると、上記ラジカル重合性重合体の全構造単位１００質量％に対して、０．５～５０質量％であることが好ましい。上記構造単位（Ａ）の含有割合は、上記ラジカル重合性重合体の全構造単位１００質量％に対して、より好ましくは１質量％以上、更に好ましくは２質量％以上であり、またより好ましくは３０質量％以下、更に好ましくは２５質量％以下である。
（一般式（１）で表される構造単位）
本発明のラジカル重合性重合体は、また、下記一般式（１）で表される構造単位（以下、「構造単位（Ｂ）」とも称する。）を有する。

The number of atoms between the acid group and the main chain is preferably 6 or less, more preferably 5 or less, and still more preferably 0.
Preferably, the acid group is directly attached to the main chain.
Examples of the acid group include functional groups capable of neutralizing reaction with alkaline water, such as carboxyl group, phenolic hydroxyl group, carboxylic acid anhydride group, phosphoric acid group, and sulfonic acid group. Among them, a carboxyl group or a carboxylic anhydride group is preferred, a carboxyl group is more preferred, and a (meth)acrylic acid group is even more preferred. An acrylic acid group is more preferable from the viewpoint of increasing the development speed.
Moreover, the said radically polymerizable copolymer has an ethylenically unsaturated double bond in a side chain. As a result, heat and photo-crosslinking reactions become possible, so that curability, development adhesion, solvent resistance, etc. are improved. In addition, the sensitivity to light is improved, curing can be performed with less light, and the mechanical strength of the cured product after curing can also be improved.
In the present invention, the ethylenically unsaturated double bond means a polymerizable double bond, ie, a carbon-carbon double bond.
Examples of the ethylenically unsaturated double bond include a (meth)acryloyl group, vinyl group, allyl group, methallyl group, and the like. The radically polymerizable polymer of the present invention may have one or more of these. Among them, a (meth)acryloyl group is preferable in terms of reactivity.
The ethylenically unsaturated double bond can be introduced into the radically polymerizable polymer, for example, by using the epoxy group-containing monomer (X) during production of the radically polymerizable polymer.
Examples of the epoxy group-containing monomer (X) include compounds containing an epoxy group and a polymerizable double bond. The polymerizable double bond is, for example, the same as the ethylenically unsaturated double bond described above, and includes a (meth)acryloyl group, a vinyl group, an allyl group, a methallyl group, and the like, and one or two of these Those having the above are suitable. Among them, a (meth)acryloyl group is preferred in terms of reactivity.
In the present specification, an epoxy group includes not only a narrowly defined epoxy group, but also a group in which an oxirane ring is bonded to carbon such as a glycidyl group, an ether bond or an ester bond such as a glycidyl ether group and a glycidyl ester group. containing groups, epoxycyclohexane rings, and the like.
Examples of the epoxy group-containing monomer (X) include glycidyl (meth)acrylate, β-methylglycidyl (meth)acrylate, β-ethylglycidyl (meth)acrylate, vinylbenzyl glycidyl ether, and allyl glycidyl ether. , (3,4-epoxycyclohexyl)methyl (meth)acrylate, vinylcyclohexene oxide, and the like. Among them, glycidyl (meth)acrylate, and/or 3,4-Epoxycyclohexylmethyl (meth)acrylate is more preferred. More preferred is glycidyl (meth)acrylate (also known as glycidyl (meth)acrylate), and particularly preferred is glycidyl methacrylate.
The radically polymerizable polymer of the present invention has a structural unit having a ring structure in its main chain and a structural unit represented by the general formula (1). Each structural unit will be explained.
(Structural unit having a ring structure in the main chain)
The radically polymerizable polymer has a structural unit having a ring structure in its main chain (hereinafter also referred to as "structural unit (A)").
By having a structural unit having a ring structure in the main chain skeleton, the heat resistance of the radically polymerizable polymer of the present invention can be improved, and the adhesiveness and solvent resistance of the cured product can be improved.
Examples of the monomer that gives the structural unit (A) include a monomer having a double bond-containing ring structure in the molecule, and a monomer that forms a polymer having a ring structure in the main chain by cyclopolymerization. etc. 1 type, or 2 or more types are suitable. Such monomers include N-substituted maleimide-based monomers, dialkyl-2,2′-(oxydimethylene) diacrylate-based monomers, and α-(unsaturated alkoxyalkyl) acrylate groups. It is preferable to use at least one more selected. Such structural units having a ring structure in the main chain are N-substituted maleimide-based monomer units, dialkyl-2,2'-(oxydimethylene) diacrylate-based monomer units, and/or α- (Unsaturated alkoxyalkyl) acrylate-based monomer units are preferred.
In particular, polymers containing N-substituted maleimide-based monomer units and/or dialkyl-2,2'-(oxydimethylene) diacrylate-based monomer units have heat resistance and dispersibility (for example, colorant and dispersibility of inorganic fine particles), hardness and the like can be further improved.
The polymer containing the above-mentioned monomer unit means a polymer containing a structural unit derived from the monomer by polymerization reaction or cross-linking reaction of the monomer, for example.
Examples of N-substituted maleimide-based monomers in the monomer component include N-cyclohexylmaleimide, N-phenylmaleimide, N-methylmaleimide, N-ethylmaleimide, N-isopropylmaleimide, and Nt-butylmaleimide. , N-dodecylmaleimide, N-benzylmaleimide, N-naphthylmaleimide and the like, and one or more of these can be used. Among them, N-cyclohexylmaleimide, N-phenylmaleimide, and N-benzylmaleimide are preferred, and N-benzylmaleimide and N-phenylmaleimide are particularly preferred in terms of less coloring and excellent dispersibility.
Examples of the N-benzylmaleimide include benzylmaleimide; alkyl-substituted benzylmaleimide such as p-methylbenzylmaleimide and p-butylbenzylmaleimide; phenolic hydroxyl group-substituted benzylmaleimide such as p-hydroxybenzylmaleimide; o-chlorobenzylmaleimide. , o-dichlorobenzylmaleimide, p-dichlorobenzylmaleimide and other halogen-substituted benzylmaleimides.
Examples of the N-phenylmaleimide include phenylmaleimide; alkyl-substituted phenylmaleimide such as p-methylphenylmaleimide and p-butylphenylmaleimide; phenolic hydroxyl group-substituted phenylmaleimide such as p-hydroxyphenylmaleimide; o-chlorophenylmaleimide; Halogen-substituted phenylmaleimides such as o-dichlorophenylmaleimide and p-dichlorophenylmaleimide are included.
As the dialkyl-2,2'-(oxydimethylene) diacrylate-based monomer, from the viewpoint of less coloring, dispersibility, and ease of industrial availability, for example, dimethyl-2,2'-[ Oxybis(methylene)]bis-2-propenoate and the like are preferably used.
Examples of the α-(unsaturated alkoxyalkyl) acrylate include α-allyloxymethyl acrylic acid, methyl α-allyloxymethyl acrylate, ethyl α-allyloxymethyl acrylate, n- Propyl, i-propyl α-allyloxymethyl acrylate, n-butyl α-allyloxymethyl acrylate, s-butyl α-allyloxymethyl acrylate, t-butyl α-allyloxymethyl acrylate, α-allyloxy n-amyl methyl acrylate, s-amyl α-allyloxymethyl acrylate, t-amyl α-allyloxymethyl acrylate, neopentyl α-allyloxymethyl acrylate, n-hexyl α-allyloxymethyl acrylate, α -s-hexyl allyloxymethyl acrylate, n-heptyl α-allyloxymethyl acrylate, n-octyl α-allyloxymethyl acrylate, s-octyl α-allyloxymethyl acrylate, α-allyloxymethyl acrylate t-octyl, 2-ethylhexyl α-allyloxymethyl acrylate, capryl α-allyloxymethyl acrylate, nonyl α-allyloxymethyl acrylate, decyl α-allyloxymethyl acrylate, undecyl α-allyloxymethyl acrylate , lauryl α-allyloxymethyl acrylate, tridecyl α-allyloxymethyl acrylate, myristyl α-allyloxymethyl acrylate, pentadecyl α-allyloxymethyl acrylate, cetyl α-allyloxymethyl acrylate, α-allyloxy heptadecyl methyl acrylate, stearyl α-allyloxymethyl acrylate, nonadecyl α-allyloxymethyl acrylate, eicosyl α-allyloxymethyl acrylate, ceryl α-allyloxymethyl acrylate, melisyl α-allyloxymethyl acrylate, etc. α-(allyloxymethyl) acrylate containing a chain saturated hydrocarbon group is preferred. In addition, alkyl-(α-methallyloxymethyl) acrylate monomers and the like are also preferred. Among them, methyl α-allyloxymethyl acrylate (also referred to as α-(allyloxymethyl)methyl acrylate) is particularly preferred.
The α-(unsaturated alkoxyalkyl) acrylate can be produced, for example, by the production method disclosed in WO 2010/114077 pamphlet.
The radically polymerizable polymer may have only one type of structural unit (A), or may have two or more types of structural units (A).
Considering compatibility between developability, transparency, and adhesion of the radically polymerizable polymer, the content of the structural unit (A) is It is preferably 0.5 to 50% by mass. The content of the structural unit (A) is more preferably 1% by mass or more, still more preferably 2% by mass or more, and more preferably 100% by mass of the total structural units of the radically polymerizable polymer. It is 30% by mass or less, more preferably 25% by mass or less.
(Structural unit represented by general formula (1))
The radically polymerizable polymer of the present invention also has a structural unit represented by the following general formula (1) (hereinafter also referred to as "structural unit (B)").

（式中、Ｒ^１は、水素原子又はメチル基を表す。Ｒ^２は、炭素数６～２０の直鎖状又は分岐状の炭化水素基を表す。）
本発明のラジカル重合性重合体は、上記構造単位（Ｂ）を有することにより、ラジカル重合性重合体溶液の粘度を低減することができる。また、現像性が向上し、耐溶剤性、密着性に優れた硬化物を与えることができる。また、主鎖との間隔が原子数６以下である酸基との組み合わせにより、無機微粒子の分散性が向上する。
上記一般式（１）中、Ｒ^１は、水素原子又はメチル基を表す。現像速度の点から、Ｒ^１は水素原子が好ましい。
上記一般式（１）中、Ｒ^２は、炭素数６～２０の直鎖状又は分岐状の炭化水素基を表す。
上記炭素数６～２０の直鎖状又は分岐状の炭化水素基としては、１－メチルペンチル基、２－メチルペンチル基、３－メチルペンチル基、４－メチルペンチル基、１，１－ジメチルブチル基、１，２－ジメチルブチル基、１，３－ジメチルブチル基、２，２－ジメチルブチル基、２，３－ジメチルブチル基、３，３－ジメチルブチル基、１－エチルブチル基、２－エチルブチル基、１，２，２－トリメチルプロピル基、１－エチル－１－メチルプロピル基、１－エチル－２－メチルプロピル基、ｎ－ヘプチル基、ｎ－オクチル基、２－エチルヘキシル基、ｎ－ノニル基、ｎ－デシル基、ｎ－ウンデシル基、ｎ－ドデシル基、ｎ－トリデシル基、ｎ－テトラデシル基、ｎ－ペンタデシル基、ｎ－ヘキサデシル基、ｎ－ヘプタデシル基、ｎ－オクタデシル基、ｎ－ノナデシル基、又はｎ－エイコシル基等を挙げることができる。
上記炭素数６～２０の直鎖状又は分岐状の炭化水素基は、炭素数６～１８の直鎖状又は分岐状の炭化水素基であることが好ましく、炭素数６～１４の直鎖状又は分岐状の炭化水素基であることがより好ましく、炭素数６～１２の直鎖状の炭化水素基であることが特に好ましい。
上記Ｒ^２としては、具体的には、好ましくはｎ－オクチル基、ｎ－ドデシル基、２－エチルヘキシル基が挙げられ、より好ましくはｎ－オクチル基、ｎ－ドデシル基が挙げられ、更に好ましくはｎ－ドデシル基が挙げられる。
上記構造単位（Ｂ）を与える単量体としては、例えば、下記一般式（１－１）で表される化合物が好ましく挙げられる。
ＣＨ_２＝ＣＲ^１－Ｃ（Ｏ）－Ｏ－Ｒ^２ （１－１）
（式中、Ｒ^１は、水素原子又はメチル基を表す。Ｒ^２は、炭素数６～２０の直鎖状又は分岐状の炭化水素基を表す。）
このような単量体化合物を含む単量体成分を重合することにより、上記構造単位（Ｂ）を有する重合体を得ることができる。
上記一般式（１－１）におけるＲ^１及びＲ^２としては、それぞれ、上記一般式（１）におけるＲ^１及びＲ^２と同様のものが挙げられる。
上記構造単位（Ｂ）を与える単量体としては、具体的には、好ましくは（メタ）アクリル酸ｎ－オクチル、（メタ）アクリル酸２－エチルヘキシル、（メタ）アクリル酸ｎ－ドデシル等が挙げられ、より好ましくは（メタ）アクリル酸ｎ－オクチル、（メタ）アクリル酸ｎ－ドデシルが挙げられる。
上記ラジカル重合性重合体は、上記構造単位（Ｂ）として、１種のみを有していてもよいし、２種以上有していてもよい。
上記構造単位（Ｂ）の含有割合は、上記ラジカル重合性重合体の取り扱い性、密着性、及び無機微粒子の分散性の両立を考慮すると、上記ラジカル重合性重合体の全構造単位１００質量％に対して、１０質量％以上であることが好ましい。上記構造単位（Ｂ）の含有割合は、上記全構造単位１００質量％に対して、より好ましくは３０質量％以上、更に好ましくは５０質量％以上であり、また、好ましくは９０質量％以下、より好ましくは８０質量％以下、更に好ましくは７０質量％以下である。

(In the formula, R ¹ represents a hydrogen atom or a methyl group. R ² represents a linear or branched hydrocarbon group having 6 to 20 carbon atoms.)
By having the structural unit (B), the radically polymerizable polymer of the present invention can reduce the viscosity of the radically polymerizable polymer solution. Moreover, the developability is improved, and a cured product having excellent solvent resistance and adhesion can be obtained. Moreover, the dispersibility of the inorganic fine particles is improved by the combination with the acid group having 6 or less atoms spaced from the main chain.
In general formula (1) above, R ¹ represents a hydrogen atom or a methyl group. From the viewpoint of development speed, R ¹ is preferably a hydrogen atom.
In general formula (1) above, R ² represents a linear or branched hydrocarbon group having 6 to 20 carbon atoms.
Examples of the linear or branched hydrocarbon group having 6 to 20 carbon atoms include 1-methylpentyl group, 2-methylpentyl group, 3-methylpentyl group, 4-methylpentyl group, 1,1-dimethylbutyl group, 1,2-dimethylbutyl group, 1,3-dimethylbutyl group, 2,2-dimethylbutyl group, 2,3-dimethylbutyl group, 3,3-dimethylbutyl group, 1-ethylbutyl group, 2-ethylbutyl group, 1,2,2-trimethylpropyl group, 1-ethyl-1-methylpropyl group, 1-ethyl-2-methylpropyl group, n-heptyl group, n-octyl group, 2-ethylhexyl group, n-nonyl group, n-decyl group, n-undecyl group, n-dodecyl group, n-tridecyl group, n-tetradecyl group, n-pentadecyl group, n-hexadecyl group, n-heptadecyl group, n-octadecyl group, n-nonadecyl group, n-eicosyl group, and the like.
The linear or branched hydrocarbon group having 6 to 20 carbon atoms is preferably a linear or branched hydrocarbon group having 6 to 18 carbon atoms, and a linear or branched hydrocarbon group having 6 to 14 carbon atoms. Or, it is more preferably a branched hydrocarbon group, and particularly preferably a straight chain hydrocarbon group having 6 to 12 carbon atoms.
Specific examples of R ² above include preferably n-octyl group, n-dodecyl group and 2-ethylhexyl group, more preferably n-octyl group and n-dodecyl group, still more preferably An n-dodecyl group can be mentioned.
Preferred examples of the monomer that provides the structural unit (B) include compounds represented by the following general formula (1-1).
_CH2 =CR1 ^- C(O)-OR2 ⁽ 1-1)
(In the formula, R ¹ represents a hydrogen atom or a methyl group. R ² represents a linear or branched hydrocarbon group having 6 to 20 carbon atoms.)
A polymer having the structural unit (B) can be obtained by polymerizing a monomer component containing such a monomer compound.
Examples of R ^{1 and R 2 in general formula (1-1) are the same as R 1 and R 2} in general formula (1) above.
Specific preferred examples of the monomer that provides the structural unit (B) include n-octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, and n-dodecyl (meth)acrylate. and more preferably n-octyl (meth)acrylate and n-dodecyl (meth)acrylate.
The radically polymerizable polymer may have only one type of structural unit (B), or may have two or more types of structural units (B).
The content of the structural unit (B) is 100% by mass of the total structural units of the radically polymerizable polymer, considering both the handleability and adhesion of the radically polymerizable polymer and the dispersibility of the inorganic fine particles. On the other hand, it is preferably 10% by mass or more. The content of the structural unit (B) is more preferably 30% by mass or more, still more preferably 50% by mass or more, and preferably 90% by mass or less, relative to 100% by mass of all the structural units. It is preferably 80% by mass or less, more preferably 70% by mass or less.

(Structural unit derived from acid group-containing monomer)
The radically polymerizable polymer of the present invention preferably further has a structural unit derived from an acid group-containing monomer (hereinafter also referred to as "structural unit (C)"). By having the structural unit (C), the radically polymerizable polymer has the acid group described above, and can exhibit developability and adhesion.
Examples of monomers that provide the structural unit (C) include acid group-containing monomers. A polymer having the structural unit (C) can be obtained by polymerizing a monomer component containing an acid group-containing monomer.
Examples of the acid group of the acid group-containing monomer include the same acid groups as those described above.
Examples of the acid group-containing monomer include unsaturated monocarboxylic acids such as (meth)acrylic acid, crotonic acid, cinnamic acid and vinylbenzoic acid; maleic acid, fumaric acid, itaconic acid, citraconic acid, mesaconic acid; Unsaturated polycarboxylic acids such as maleic anhydride and itaconic anhydride; Unsaturated acid anhydrides such as maleic anhydride and itaconic anhydride; Phosphate group-containing unsaturated compounds such as Light Ester P-1M (manufactured by Kyoeisha Chemical Co., Ltd.); Among these, carboxylic acid-based monomers (unsaturated monocarboxylic acids, unsaturated polycarboxylic acids, unsaturated acid anhydrides) are preferably used from the viewpoint of versatility, availability, and the like. Unsaturated monocarboxylic acids are more preferred, and (meth)acrylic acid is even more preferred from the viewpoint of reactivity, heat-resistant color resistance, and the like. Thus, in the radically polymerizable polymer, the acid group is preferably a carboxyl group derived from (meth)acrylic acid.
The radically polymerizable polymer may have only one type of structural unit (C), or may have two or more types of the structural unit (C). It is preferable to have a structural unit having an acid group with an interval of 6 atoms or less. The acid group having a distance of 6 atoms or less from the main chain is as described above.
Considering compatibility between developability, handleability, and adhesion of the radically polymerizable polymer, the content of the structural unit (C) is It is preferably 1 to 50% by mass. The content of the structural unit (C) is more preferably 5% by mass or more, still more preferably 10% by mass or more, and more preferably 45% by mass or less, and further It is preferably 40% by mass or less, particularly preferably 35% by mass or less.
(Structural Unit Having Ring Structure in Side Chain)
The radically polymerizable polymer of the invention may also have a ring structure in its side chain. That is, the radically polymerizable polymer may have a structural unit having a ring structure in its side chain (hereinafter also referred to as "structural unit (D)"). By having a ring structure in the side chain, the hydrophobicity of the radically polymerizable polymer can be improved, and the solvent resistance can be improved.
Examples of the ring structure include an aromatic ring structure such as benzene, or an alicyclic structure such as a cyclohexane skeleton, an adamantane skeleton, and a norbornene skeleton.
In order for the radically polymerizable polymer to have a ring structure in the side chain, it is preferable to polymerize a monomer component containing a monomer having an aromatic hydrocarbon group or an alicyclic hydrocarbon group and a polymerizable double bond. .
Examples of the aromatic hydrocarbon group include aryl groups such as benzyl, tolyl, naphthyl and biphenyl.
The alicyclic hydrocarbon group preferably has 3 to 20 carbon atoms, more preferably 3 to 15 carbon atoms. Specific examples of the alicyclic hydrocarbon group include monocyclic hydrocarbon groups such as cyclopropyl, cyclopentyl, cyclohexyl, cyclooctyl, cyclododecyl, cycloheptyl, cyclobutenyl, cyclopentenyl, and cyclohexenyl; Examples include polycyclic hydrocarbon groups such as pentanyl, dicyclopentenyl, tricyclodecanyl, adamantyl, and isobornyl. These may have a substituent.
Examples of the polymerizable double bond are the same as the ethylenically unsaturated double bond described above, and include a (meth)acryloyl group, a vinyl group, an allyl group, a methallyl group, and the like. Among them, a (meth)acryloyl group is preferred in terms of reactivity.
Specific examples of monomers that provide the structural unit (D) include cyclohexyl (meth)acrylate, cyclohexylmethyl (meth)acrylate, isobornyl (meth)acrylate, 1-adamantyl (meth)acrylate, (3 , 4-epoxycyclohexyl)methyl (meth)acrylate, dicyclopentanyl (meth)acrylate, dicyclopentenyl (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, tricyclodecanyl (meth)acrylate, dimethylol- Alicyclic hydrocarbon group-containing monomers such as tricyclodecane di(meth)acrylate, pentacyclopentadecanedimethanol di(meth)acrylate, cyclohexanedimethanol di(meth)acrylate, norbornanedimethanol di(meth)acrylate; Aromatic hydrocarbon group-containing monomers such as benzyl (meth)acrylate and 1-mol ethoxylated phenylphenol acrylate can be mentioned. Among these, alicyclic hydrocarbon group-containing monomers are preferred, and cyclohexyl (meth)acrylate is more preferred, in that they can improve hydrophobicity.
The content of the structural unit (D) is preferably 1 to 60% by mass, more preferably 3 to 50% by mass, based on 100% by mass of the total structural units of the radically polymerizable polymer. , more preferably 5 to 40% by mass.
The radically polymerizable polymer may have only one type of structural unit (D), or may have two or more types of structural units (D).
However, when the radically polymerizable polymer has a structural unit represented by the following general formula (2) as the structural unit (D), the content ratio is 100 mass of all structural units of the radically polymerizable polymer. % is 5% by mass or less. Substantially free is particularly preferred.
The hydrogen atom at the benzylic position represented by the following general formula (2) is cut off, and radicals are likely to be generated in the main chain, and the oxidation of the main chain may reduce the heat-resistant coloring resistance of the cured product of the radically polymerizable polymer. There is In addition, the aromatic ring may absorb light and reduce the transparency of the cured product. In addition, in the photosensitive resin composition of the present invention containing inorganic fine particles, the dispersibility of the inorganic fine particles tends to decrease. Therefore, it is desirable that the content of the structural unit represented by the following general formula (2) is within the range described above.
Specifically, the content ratio of the structural unit represented by the following general formula (2) is preferably 3% by mass or less with respect to 100% by mass of the total structural units of the radically polymerizable polymer, and 1% by mass. It is more preferably below, and still more preferably 0% by mass.

（式中、Ｒ^３は、水素原子又はメチル基を表す。）
上記一般式（２）で表される構造単位を与える単量体としては、スチレン、ビニルトルエンが挙げられる。
上記構造単位（Ｄ）として、上記一般式（２）で表される構造単位と、それ以外の他の構造単位を有する場合は、上記他の構造単位の含有割合は、ラジカル重合性重合体の全構造単位１００質量％に対して、好ましくは１～６０質量％、より好ましくは、３～５０質量％である。また、上記一般式（２）で表される構造単位の含有割合は、ラジカル重合性重合体の全構造単位１００質量％に対して５質量％以下、好ましくは３質量％以下、より好ましくは１質量％以下、更に好ましくは０質量％である。

( ^In the formula, R3 represents a hydrogen atom or a methyl group.)
Examples of monomers that give the structural unit represented by the general formula (2) include styrene and vinyltoluene.
As the structural unit (D), when the structural unit represented by the general formula (2) and other structural units are included, the content of the other structural units is It is preferably 1 to 60% by mass, more preferably 3 to 50% by mass, based on 100% by mass of all structural units. The content ratio of the structural unit represented by the general formula (2) is 5% by mass or less, preferably 3% by mass or less, more preferably 1% by mass, based on 100% by mass of the total structural units of the radically polymerizable polymer. % by mass or less, more preferably 0% by mass.

(other structural units)
The above radically polymerizable polymer may further have other structural units (E) as necessary.
As the other structural unit (E), for example, a (meth)acrylic acid ester-based monomer other than the monomer that provides the structural unit (B), a hydroxyl group-containing monomer, or other copolymerizable and structural units derived from such monomers.
Examples of the (meth)acrylic acid ester-based monomer other than the monomer giving the structural unit (B) include methyl (meth)acrylate, ethyl (meth)acrylate, and n-propyl (meth)acrylate. , (meth) i-propyl acrylate, n-butyl (meth) acrylate, t-butyl (meth) acrylate, 1-methylpropyl (meth) acrylate, 2-methylpropyl (meth) acrylate, (meth) ) 1,1-dimethylethyl acrylate, n-pentyl (meth)acrylate, 1-methylbutyl (meth)acrylate, 2-methylbutyl (meth)acrylate, 3-methylbutyl (meth)acrylate, (meth)acrylic acid 2,2-dimethylpropyl acid, 1-ethylpropyl (meth)acrylate, n-hexyl (meth)acrylate, 1,1-dimethylpropyl (meth)acrylate, 1,2-dimethylpropyl (meth)acrylate , 2-methoxyethyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, N,N-dimethylaminoethyl (meth)acrylate, 1,4-dioxaspiro [4 , 5] Dec-2-ylmethacrylic acid, (meth)acryloylmorpholine, 4-(meth)acryloyloxymethyl-2-methyl-2-ethyl-1,3-dioxolane, 4-(meth)acryloyloxymethyl- 2-methyl-2-isobutyl-1,3-dioxolane, 4-(meth)acryloyloxymethyl-2-methyl-2-cyclohexyl-1,3-dioxolane, 4-(meth)acryloyloxymethyl-2,2- dimethyl-1,3-dioxolane and the like.
Examples of the hydroxyl group-containing monomers include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, and 2-hydroxybutyl (meth)acrylate. , 3-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate and 2,3-hydroxypropyl (meth)acrylate.
Examples of other copolymerizable monomers include one or more of the following compounds.
(Meth)acrylamides such as N,N-dimethyl (meth)acrylamide and N-methylol (meth)acrylamide; polystyrene, polymethyl (meth)acrylate, polyethylene oxide, polypropylene oxide, polysiloxane, polycaprolactone, polycaprolactam and the like; Macromonomers having a (meth)acryloyl group at one end of the combined molecular chain; Conjugated dienes such as 1,3-butadiene, isoprene and chloroprene; Vinyl esters such as vinyl acetate, vinyl propionate, vinyl butyrate and vinyl benzoate Class; methyl vinyl ether, ethyl vinyl ether, propyl vinyl ether, butyl vinyl ether, 2-ethylhexyl vinyl ether, n-nonyl vinyl ether, lauryl vinyl ether, cyclohexyl vinyl ether, methoxyethyl vinyl ether, ethoxyethyl vinyl ether, methoxyethoxyethyl vinyl ether, methoxypolyethylene glycol vinyl ether, 2- vinyl ethers such as hydroxyethyl vinyl ether and 4-hydroxybutyl vinyl ether; N-vinyl compounds such as N-vinylpyrrolidone, N-vinylcaprolactam, N-vinylimidazole, N-vinylmorpholine and N-vinylacetamide; (meth) Examples include unsaturated isocyanates such as isocyanatoethyl acrylate and allyl isocyanate.
The radically polymerizable polymer may have only one type of the structural unit (E), or may have two or more types of the structural unit (E).
The content of the structural unit (E) is preferably 0 to 60% by mass, more preferably 0.3 to 50% by mass, based on 100% by mass of the total structural units of the radically polymerizable polymer. It is preferably 0.5 to 40% by mass.
The double bond equivalent weight of the radically polymerizable polymer is 330 to 1600 g/equivalent (mol). When the double bond equivalent is within the above range, the curability (sensitivity to heat and light) of the radically polymerizable polymer is improved, and the adhesion of the cured product is improved. Moreover, coloring at the time of hardening can be reduced. The double bond equivalent is preferably 400 g/equivalent or more, more preferably 500 g/equivalent or more, and still more preferably 550 g/equivalent or more from the viewpoint of achieving both curability and storage stability. From the viewpoint of properties, it is preferably 1500 g/equivalent or less, more preferably 1400 g/equivalent or less, and still more preferably 1300 g/equivalent or less.
As used herein, the double bond equivalent is the mass (g) of the solid content of the polymer solution per 1 mol of the double bond of the polymer. The mass of the solid content of the polymer solution is the mass of each monomer component constituting the polymer (for example, the mass of the base polymer component, the functional group capable of bonding with an acid group, and the polymerizable double bond group. is the sum of the masses of compounds having The double bond equivalent can be obtained by dividing the mass (g) of the polymer solid content in the polymer solution by the double bond amount (mol) of the polymer. The amount of double bonds in the polymer is determined by the amount of the acid group-containing monomer used in the polymerization and the compound having a polymerizable double bond (a functional group capable of bonding with an acid group and a compound having a polymerizable double bond ) and can be determined from their quantities. It can also be measured by titration, elemental analysis, various analyzes such as NMR and IR, and differential scanning calorimetry. For example, it may be calculated by measuring the number of ethylenic double bonds contained per 1 g of the polymer in accordance with the iodine value test method described in JIS K 0070:1992. The double bond equivalent is a measure of the amount of double bonds contained in a molecule. For compounds with the same molecular weight, the larger the double bond equivalent, the less double bonds are introduced. Become.
The weight average molecular weight of the radically polymerizable polymer is 3,000 to 14,000. When the weight-average molecular weight is within the above range, the viscosity can be adjusted to an appropriate range, the handleability is good, and the adhesion is further improved. The weight average molecular weight is more preferably 4,000 to 13,000, even more preferably 5,000 to 12,000, and particularly preferably 7,000 to 12,000.
In the present specification, the weight average molecular weight can be determined by the method described in Examples below.
The acid value of the radically polymerizable polymer is preferably 50 to 150 mgKOH/g. When the acid value is within the above range, not only is the alkali solubility more expressed, but also the adhesiveness of the cured product is further improved, and the dispersibility of the inorganic fine particles is more appropriate. In addition, the dispersibility of the radically polymerizable polymer is also improved. The acid group is more preferably 60 to 150 mgKOH/g, even more preferably 70 to 150 mgKOH/g.
In the present specification, the acid value can be determined by the method described in Examples below.
The glass transition temperature (Tg) of the radically polymerizable polymer is preferably 50° C. or lower. When the glass transition temperature is within the above range, the viscosity can be adjusted to an appropriate range, the handleability is improved, and the developability and adhesion are excellent. The glass transition temperature is preferably 40° C. or lower, more preferably 30° C. or lower, and even more preferably 0° C. or lower. From the viewpoint of heat resistance, the glass transition temperature is preferably −50° C. or higher, more preferably −30° C. or higher.
In the present specification, the glass transition temperature can be determined by the method described in Examples below.

(Method for producing radically polymerizable polymer)
A method for producing the radically polymerizable polymer of the present invention will be described.
The method for obtaining the above-mentioned radically polymerizable polymer is not particularly limited, but for example, (1) a monomer (a) giving the structural unit (A) described above and a monomer giving the structural unit (B) described above (b) and a polymer obtained by polymerizing a monomer component containing at least the acid group-containing monomer (c) (hereinafter also referred to as “base polymer 1”), the above-mentioned epoxy group-containing monomer (2) a monomer component containing at least the monomer (a), the monomer (b), and the epoxy group-containing monomer (X); Examples thereof include a method of reacting a polymer obtained by polymerization (hereinafter also referred to as "base polymer 2") with the acid group-containing monomer (c). That is, the radically polymerizable polymer is a reaction product of the base polymer 1 and the epoxy group-containing monomer (X), or a reaction product of the base polymer 2 and the acid group-containing monomer (c). Preferably. Among them, from the viewpoint of production efficiency with respect to acid group introduction, a reaction product between base polymer 1 and epoxy group-containing monomer (X) is preferred.
The synthesis method will be described below.
Method (1)
When the radically polymerizable polymer is obtained by the method (1), the monomer components that give the base polymer 1 are the monomer (a), the monomer (b), and the acid group-containing monomer. (c) is included at least.
The ratio of each monomer shown in the monomer component is not particularly limited as long as a radically polymerizable polymer having excellent handleability (coating workability), transparency and adhesion of the cured product can be obtained. The content ratio of the monomers (a), (b), and (c) is 0.5 to 30% by mass of the monomer (a) with respect to 100% by mass of the total amount of the monomer components that provide the base polymer 1. %, the monomer (b) 11 to 85% by mass, the monomer (c) 5 to 85% by mass, the monomer (a) 1 to 25% by mass, the monomer More preferably, (b) is 15 to 80% by mass and the monomer (c) is 10 to 70% by mass.
Further, the monomer component that provides the base polymer 1 includes the monomer (a), the monomer (b), the monomer (c), and the monomer that provides the structural unit (D). When the monomer (d) is contained, the content ratio of each monomer is 0.5 to 30% by mass of the above monomer (a), the above It is preferable that the monomer (b) is 11 to 85% by mass, the monomer (c) is 5 to 85% by mass, and the monomer (d) is 1 to 70% by mass. 1 to 25% by mass, 15 to 80% by mass of the monomer (b), 10 to 70% by mass of the monomer (c), and 5 to 40% by mass of the monomer (d). .
Further, the monomer components that provide the base polymer 1 are the monomer (a), the monomer (b), the monomer (c), the monomer (d), and the structure When the monomer (e) that gives the unit (E) is included, the content ratio of each monomer is 0 to 100% by mass of the total amount of the monomer components that give the base polymer 1. .5 to 30% by mass, 11 to 85% by mass of the above monomer (b), 5 to 85% by mass of the above monomer (c), 1 to 70% by mass of the above monomer (d), the above monomer (e) is preferably 0 to 70 mass%, the monomer (a) 1 to 25 mass%, the monomer (b) 15 to 80 mass%, the monomer (c) 10 to 70 5 to 40% by mass of the monomer (d) and 1 to 40% by mass of the monomer (e).
In the above method (1), the method of polymerizing the monomer component is not particularly limited, and commonly used methods such as bulk polymerization, solution polymerization, and emulsion polymerization can be used, and can be appropriately selected depending on the purpose and application. do it. Among them, solution polymerization is industrially advantageous, and structural adjustment such as molecular weight is easy, and therefore, it is preferable. In addition, as the polymerization mechanism of the monomer component, a polymerization method based on a mechanism such as radical polymerization, anionic polymerization, cationic polymerization, or coordination polymerization can be used. is also advantageous, so it is preferable. Preferred forms of the polymerization reaction are as described in [0062] to [0072] of JP-A-2016-29151.
The polymerization initiation method in the above polymerization reaction may be performed by supplying energy necessary for polymerization initiation from an active energy source such as heat, electromagnetic waves (e.g., infrared rays, ultraviolet rays, X-rays), and electron beams to the monomer components. Combined use of an initiator is preferable because the energy required for polymerization initiation can be greatly reduced and the reaction can be easily controlled. Further, the molecular weight of the polymer obtained by polymerizing the above monomer components can be controlled by adjusting the amount and type of the polymerization initiator, the polymerization temperature, the type and amount of the chain transfer agent, and the like.
In the above method (1), some of the acid groups contained in the base polymer 1 are subjected to an addition reaction with the epoxy group-containing monomer (X). The reaction method is not particularly limited, and a known method may be employed as appropriate. For example, the reaction temperature is preferably 60 to 140°C. Amine compounds such as triethylamine and dimethylbenzylamine; ammonium salts such as tetraethylammonium chloride; phosphonium salts such as tetraphenylphosphonium bromide; and amide compounds such as dimethylformamide.
The amount of the epoxy group-containing monomer (X) used is preferably set appropriately so that the acid value and double bond equivalent are within the desired ranges. It is preferably 1 to 90 parts by mass with respect to the total amount of 100 parts by mass. As a result, the adhesiveness is further improved, the curability is further enhanced, and the strength of the cured product is further enhanced. More preferably 3 to 85 parts by mass, still more preferably 5 to 80 parts by mass.
In addition, the amount of the epoxy group-containing monomer (X) used is 10 to 95 mol% with respect to 100 mol% of the acid group-containing monomer (c) in the monomer component that provides the base polymer 1. preferably 15 to 90 mol %, and even more preferably 20 to 85 mol %.
Method (2)
When the radical polymerizable polymer is obtained by the method (2), the monomer components that give the base polymer 2 are the monomer (a), the monomer (b) and the epoxy group-containing monomer. (X) is included at least.
The ratio of each monomer in the monomer components is not particularly limited, but for example, the content ratio of the monomer (a) with respect to 100% by mass of the total amount of the monomer components that give the base polymer 2 is It is preferably 0.5 to 30% by mass, more preferably 1 to 20% by mass, and the content of the monomer (b) is preferably 15 to 90% by mass, more preferably 20 to 80% by mass. be.
The content of the epoxy group-containing monomer (X) is preferably set appropriately so that the acid value and double bond equivalent are within the ranges described above. It is preferably 3 to 80% by mass, more preferably 5 to 75% by mass, relative to the total amount of 100% by mass.
Further, the monomer component that provides the base polymer 2 includes the monomer (a), the monomer (b), the epoxy group-containing monomer (X), and the monomer (d). When it is contained, the content ratio of each monomer is 0.5 to 30% by mass of the monomer (a) and the monomer ( b) 15 to 90% by mass, 3 to 80% by mass of the epoxy group-containing monomer, preferably 1 to 70% by mass of the monomer (d), and 1 to 20% by mass of the monomer (a) %, 19 to 80% by mass of the monomer (b), 5 to 75% by mass of the epoxy group-containing monomer (X), and 5 to 40% by mass of the monomer (d).
Further, the monomer components that give the base polymer 2 are the monomer (a), the monomer (b), the epoxy group-containing monomer (X), the monomer (d), and When the above monomer (e) is included, the content ratio of each monomer is 0.5 to 30% of the monomer (a) with respect to 100% by mass of the total amount of the monomer components that give the base polymer 2. mass%, the monomer (b) 15 to 90 mass%, the epoxy group-containing monomer (X) 3 to 80 mass%, the monomer (d) 1 to 70 mass%, the monomer ( e) is preferably 0 to 70% by mass, the above monomer (a) 0.5 to 20% by mass, the above monomer (b) 19 to 80% by mass, the epoxy group-containing monomer (X ) is 5 to 75% by mass, the monomer (d) is 5 to 40% by mass, and the monomer (e) is 0.5 to 40% by mass.
In the above method (2), the method of polymerizing the monomer component is not particularly limited, and is the same as the polymerization method described in the above method (1).
In the above method (2), some of the epoxy groups contained in the base polymer 2 are subjected to an addition reaction with the acid group-containing monomer (c). Although this reaction method is not particularly limited, it is preferable to set the reaction temperature to 60°C to 140°C, for example. Amine compounds such as triethylamine and dimethylbenzylamine; ammonium salts such as tetraethylammonium chloride; phosphonium salts such as tetraphenylphosphonium bromide; and amide compounds such as dimethylformamide.
The amount of the acid group-containing monomer (c) to be used is preferably 1 to 60 parts by weight per 100 parts by weight of the total amount of the monomer components that give the base polymer 2 . As a result, the adhesiveness is further improved, the curability is further increased, and the strength of the cured product is more sufficient. More preferably 2 to 50 parts by mass, still more preferably 3 to 40 parts by mass.
It is also preferable to react a polybasic acid anhydride after the addition reaction of the acid group-containing monomer (c). In this reaction, carboxyl groups are generated by reacting polybasic acid anhydride with hydroxyl groups generated by the reaction between the epoxy groups contained in the base polymer 2 and the acid group-containing monomer (c). By carrying out this reaction, the acid value can be adjusted to an appropriate amount.
The polybasic acid anhydride is not particularly limited, but examples include succinic anhydride (also known as succinic anhydride), maleic anhydride, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, and methyltetrahydrophthalic anhydride. , methylhexahydrophthalic anhydride, endomethylenetetrahydrophthalic anhydride, methylendomethylenetetrahydrophthalic anhydride, dibasic acid anhydrides such as itaconic anhydride; trimellitic anhydride;
The amount of the polybasic acid anhydride to be used is not particularly limited, and is preferably set so that the acid value of the obtained radically polymerizable polymer falls within the range described above.
In the synthesis, it is preferable to set the amount of the solvent and each monomer component so that the final solid content concentration of the radically polymerizable polymer solution is 10 to 70% by mass. From the viewpoints of productivity and polymerizability, the final solid content (non-volatile content) is more preferably 20 to 65% by mass, more preferably 25 to 60% by mass.
The radically polymerizable polymer of the present invention is excellent in handleability (coating workability) and can give a cured product with excellent transparency. Therefore, it is useful as an alkali-developable negative resist material for producing colored pixels of color filters, black matrixes, black column spacers, overcoats, photospacers, optical waveguides, and the like. Moreover, since it has good inorganic fine particle dispersibility, coloring material dispersibility and adhesion, it is also useful for a colored photosensitive resin composition for color filters. The above-mentioned radically polymerizable polymer is preferably used as an alkali-soluble resin, etc., for binder resins for color resists, and the above-mentioned radically polymerizable polymer is extremely useful as a main component of a photosensitive resin composition.

2. Photosensitive resin composition The radically polymerizable polymer described above can be made into a photosensitive resin composition further containing a polyfunctional monomer. Moreover, it can be made into the photosensitive resin composition containing a photoinitiator, an inorganic fine particle, and a solvent as needed. Since the above-mentioned photosensitive resin composition contains the above-mentioned polymer, it is easy to handle, is excellent in coating workability, and can give a cured product excellent in transparency and adhesion. In addition, by further including a polyfunctional monomer, it is possible to give a cured product excellent in various physical properties such as curability of the resin composition, adhesion to substrates, mechanical strength and heat resistance. Such a photosensitive resin composition containing the radically polymerizable polymer and the polyfunctional monomer is also one aspect of the present invention. Although the application is not limited, it is suitably used as a material for forming protective films of color filters, liquid crystal display elements, integrated circuit elements, solid-state imaging elements, and the like.
In the photosensitive resin composition, the content of the radically polymerizable polymer is preferably 5% by mass or more and 70% by mass or less with respect to 100% by mass of the total solid content of the photosensitive resin composition. It is preferable to have Within such a range, the effects of the present invention can be exhibited more remarkably. More preferably 10 to 65% by mass, still more preferably 10 to 50% by mass, particularly preferably 10 to 40% by mass, still more preferably 10 to 35% by mass, most preferably 15 to 35% by mass. The term "total solid content" means the total amount of components forming the cured product (excluding the solvent and the like that volatilize during the formation of the cured product).
In the above photosensitive resin composition, the polyfunctional monomer is a polymerizable unsaturated bond (polymerization It is a low-molecular-weight compound having a polyunsaturated group). Examples thereof include polyfunctional compounds having two or more polymerizable unsaturated groups in the molecule. Although the molecular weight is not particularly limited, it is preferably 3,000 or less, more preferably 2,000 or less, from the viewpoint of handling. Among them, a polyfunctional (meth)acrylate compound having a functionality of 2 or more (hereinafter also simply referred to as a "polyfunctional (meth)acrylate compound") is particularly preferred. It is a compound having two or more (meth)acryloyl groups in one molecule. By containing such a compound, the photosensitive resin composition becomes excellent in photosensitivity and curability, and it becomes possible to obtain a cured film with extremely high hardness and high transparency. The functionality of the polyfunctional (meth)acrylate compound is preferably 3 or more, more preferably 4 or more, still more preferably 5 or more. Moreover, from the viewpoint of further suppressing curing shrinkage, the functional number is preferably 10 or less, more preferably 8 or less, and still more preferably 6 or less.
Examples of the polyfunctional monomer include (di)ethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, trimethylolpropane di(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol di(meth) ) acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol di(meth)acrylate, dipentaerythritol tri(meth)acrylate, dipentaerythritol tetra(meth)acrylate, dipentaerythritol penta Polyfunctional (meth)acrylates such as (meth)acrylate, dipentaerythritol hexa(meth)acrylate, tris(hydroxyethyl)isocyanurate tri(meth)acrylate, and the like. Among these, trimethylolpropane tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate, ethylene oxide-added dipentaerythritol hexa(meth)acrylate, propylene oxide-added trimethylolpropane tri(meth)acrylate, ) acrylate, propylene oxide-added ditrimethylolpropane tetra(meth)acrylate, propylene oxide-added pentaerythritol tetra(meth)acrylate, propylene oxide-added dipentaerythritol hexa(meth)acrylate, ε-caprolactone-added trimethylolpropane tri(meth)acrylate , ε-caprolactone-added ditrimethylolpropane tetra(meth)acrylate, ε-caprolactone-added pentaerythritol tetra(meth)acrylate, and ε-caprolactone-added dipentaerythritol hexa(meth)acrylate are preferable.
The content of the polyfunctional monomer may be appropriately set according to the type of the polyfunctional monomer and the radically polymerizable polymer used, as well as the purpose and application. From a viewpoint, it is preferably 2% by mass or more and preferably 85% by mass or less with respect to 100% by mass of the total solid content of the photosensitive resin composition. The lower limit is more preferably 5% by mass or more, still more preferably 10% by mass or more, particularly preferably 15% by mass or more, and the upper limit is more preferably 75% by mass or less, still more preferably 60% by mass or less, and particularly preferably. is 50 mass % or less, most preferably 40 mass % or less.
Moreover, the content of the polyfunctional monomer is preferably 50 parts by mass or more and 500 parts by mass or less with respect to 100 parts by mass of the radically polymerizable polymer. When the content of the polyfunctional monomer is within this range, a cured film having a higher surface hardness can be obtained, and the developability is further improved, coupled with the preferred weight-average molecular weight of the radically polymerizable polymer being 5000 or more. will be More preferably 80 parts by mass or more, still more preferably 100 parts by mass or more, and particularly preferably 120 parts by mass or more. Moreover, from the viewpoint of further improving developability, it is more preferably 400 parts by mass or less. More preferably 300 parts by mass or less, particularly preferably 200 parts by mass or less, and most preferably 150 parts by mass or less.
In the photosensitive resin composition, it is preferable to use light or a thermal polymerization initiator when curing the photosensitive resin composition. Examples of photopolymerization initiators include diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, benzyldimethylketal, 4-(2-hydroxyethoxy)phenyl-(2-hydroxy-2 -propyl)ketone, 1-hydroxycyclohexylphenylketone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1-(4- morpholinophenyl)butanone, oligo{2-hydroxy-2-methyl-1-[4-(1-methylvinyl)phenyl]propanone}, 2-hydroxy-1-{4-[4-(2-hydroxy-2- acetophenones such as methylpropionyl)benzyl]phenyl}-2-methylpropan-1-one; benzoins such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, and benzoin isobutyl ether; benzophenone, methyl o-benzoylbenzoate , 4-phenylbenzophenone, 4-benzoyl-4′-methyl-diphenylsulfide, 3,3′,4,4′-tetra(t-butylperoxycarbonyl)benzophenone, 2,4,6-trimethylbenzophenone, 4-benzoyl -N,N-dimethyl-N-[2-(1-oxo-2-propenyloxy)ethyl]benzenemethanaminium bromide, (4-benzoylbenzyl)trimethylammonium chloride and other benzophenones; 2-isopropylthioxanthone, 4 -isopropylthioxanthone, 2,4-diethylthioxanthone, 2,4-dichlorothioxanthone, 1-chloro-4-propoxythioxanthone, 2-(3-dimethylamino-2-hydroxy)-3,4-dimethyl-9H-thioxanthone- Thioxanthones such as 9-one mesochloride, phenylglyoxylic methyl ester, 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide etc. Among these, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one and 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butanone are preferred.

For example, cumene hydroperoxide, diisopropylbenzene hydroperoxide, di-t-butyl peroxide, lauroyl peroxide, benzoyl peroxide, t-butylperoxyisopropyl carbonate, t-amylperoxy-2-ethylhexanoate, Organic peroxides such as t-butyl peroxy-2-ethylhexanoate; 2,2'-azobis(isobutyronitrile), 1,1'-azobis(cyclohexanecarbonitrile), 2,2'-azobis azo compounds such as (2,4-dimethylvaleronitrile) and dimethyl 2,2′-azobis(2-methylpropionate); These photopolymerization initiators may be used alone or in combination of two or more.

Particularly preferred specific polymerization initiators include 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one (“IRGACURE907”, manufactured by BASF), 2-benzyl-2 -dimethylamino-1-(4-morpholinophenyl)-butanone-1 ("IRGACURE369", manufactured by BASF), 2-dimethylamino-2-(4-methyl-benzyl)-1-(4-morpholine- 4-yl-phenyl)-butan-1-one (“IRGACURE379”, manufactured by BASF) and other aminoketone compounds;
Bis(η5-2,4-cyclopentadien-1-yl)-bis(2,6-difluoro-3-(1H-pyrrol-1-yl)-phenyl) titanium (“IRGACURE784”, manufactured by BASF) and the like titanocene compounds;
oxime ester compounds such as 1,2-octanedione, 1-[4-(phenylthio)-,2-(O-benzoyloxime)] ("IRGACURE OXE01", manufactured by BASF);
Among the above photopolymerization initiators, it is particularly preferable to use at least an aminoketone-based compound (also referred to as an aminoketone-based polymerization initiator). That is, the photosensitive resin composition preferably further contains an aminoketone-based polymerization initiator. Thereby, hardness and heat resistance become more excellent.
The content of the photopolymerization initiator may be appropriately set according to the purpose, application, etc., and is not particularly limited. It is preferable to have Thereby, a cured film having excellent heat resistance and adhesiveness can be obtained. It is more preferably 1 part by mass or more, still more preferably 1.5 parts by mass or more. Further, considering the influence of the decomposed product of the photopolymerization initiator and the balance with economic efficiency, etc., it is preferably 30 parts by mass or less. It is more preferably 20 parts by mass or less, still more preferably 10 parts by mass or less.
The photosensitive resin composition preferably contains inorganic fine particles in order to increase the hardness of a cured film obtained by curing the photosensitive resin composition.
As the inorganic fine particles, in addition to silicon oxide such as silica described above, metal oxides such as titanium oxide, aluminum oxide, and zirconium oxide (such as zirconia); metal salts such as calcium carbonate and barium sulfate; are preferable. Among them, metal oxides are more preferable. It may be a composite metal oxide containing two or more metal atoms. Metal oxide particles having hydroxyl groups on the surface are more preferred, and silica particles are particularly preferred. Among them, surface-modified silica fine particles are preferable, and for example, those surface-modified with a (meth)acryloyloxy group bonded to a silicon atom via a divalent linking group are more preferable.
In the inorganic fine particles, radical polymerization having a hydrocarbon group having 6 to 20 carbon atoms in the structural unit (B) contained in the photosensitive resin composition of the present invention and an acid group having 6 atoms or less apart from the main chain It has good affinity with the polar polymer and good dispersibility.
The number average primary particle size (diameter of primary particles) of the inorganic fine particles is preferably, for example, 1 to 500 nm. Within this range, the dispersibility and dispersion stability of the inorganic fine particles become more sufficient, and it becomes possible to provide a cured film with excellent dispersibility and high transparency. More preferably, the number average primary particle size is 1 to 300 nm, still more preferably 1 to 200 nm, particularly preferably 1 to 100 nm, and most preferably 1 to 50 nm.
The number average primary particle size can be measured, for example, using a laser diffraction particle size distribution analyzer. Directly, the number average primary particle diameter can be determined by observing inorganic fine particles with a transmission electron microscope (TEM), a field emission transmission electron microscope (FE-TEM), a field emission scanning electron microscope (FE-SEM), or the like. It can be determined by magnifying observation, randomly selecting 100 primary particles, measuring the length in the major axis direction, and calculating the arithmetic mean.
The inorganic fine particles may be in the form of dried powder, or may be in the form of a dispersion dispersed in an organic solvent (for example, colloidal silica). From the standpoint of dispersion stability, it is preferable to use a dispersion form dispersed in an organic solvent. That is, the inorganic fine particles are preferably contained in the photosensitive resin composition as an organic solvent dispersion. Particle shapes include spherical, granular, ellipsoidal, cubic, rectangular parallelepiped, pyramidal, needle, columnar, rod-like, cylindrical, scale-like, plate-like, and flake-like. Considering dispersibility in a solvent, etc., the particle shape is preferably spherical, granular, columnar, or the like. Further, specific examples of the organic solvent include various solvents described in JP-A-2013-227485 [0024].
The organic solvent dispersion can be obtained by sufficiently dispersing inorganic fine particles in an organic solvent, but a commercially available product can also be used. Examples thereof include various organosilica sols (for example, NBAC-ST (organosilica sol using butyl acetate as a dispersion medium)) exemplified in JP-A-2013-227485 [0026].
When the photosensitive resin composition contains inorganic fine particles, the content (solid content) is preferably 5% by mass or more in 100% by mass of the total solid content of the photosensitive resin composition. More preferably 7 mass % or more, still more preferably 10 mass % or more. Moreover, from the viewpoint of developability, transparency, etc., the content is preferably 50% by mass or less. More preferably, it is 40% by mass or less.
When at least a silicon-containing compound (preferably silica fine particles) is used as the inorganic fine particles, the content (solid content) is 50 parts by mass or more with respect to 100 parts by mass of the total amount of inorganic fine particles in the photosensitive resin composition. is preferred. More preferably 70 parts by mass or more, still more preferably 90 parts by mass or more, and most preferably 100 parts by mass.
The photosensitive resin composition (preferably negative photosensitive resin composition) of the present invention preferably contains a solvent as a diluent, if necessary. The solvent is not particularly limited as long as it can uniformly dissolve components such as the polymer, polyfunctional monomer, photopolymerization initiator and inorganic fine particles. Specifically, for example, ethers such as tetrahydrofuran, dioxane, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone; ethyl acetate, butyl acetate, propylene glycol monomethyl ether acetate, 3- Esters such as methoxybutyl acetate; Alcohols such as methanol, ethanol, isopropanol, n-butanol, ethylene glycol monomethyl ether, propylene glycol monomethyl ether; Aromatic hydrocarbons such as toluene, xylene, ethylbenzene; Chloroform, dimethyl sulfoxide; etc. The content of the solvent may be appropriately set according to the optimum viscosity when using the photosensitive resin composition. For example, it is 1000 parts by mass or less, more preferably 700 parts by mass or less with respect to 100 parts by mass of the polymer. A preferable lower limit is 30 parts by mass or more, more preferably 60 parts by mass or more, relative to 100 parts by mass of the polymer. By controlling the value within the above numerical range, the handling property and storage stability of the composition, as well as the efficiency during the coating operation, are improved.
The viscosity of the photosensitive resin composition can be appropriately set according to the desired thickness of the cured film. The viscosity of the photosensitive resin composition can be adjusted by adding a solvent. The upper limit of the viscosity of the photosensitive resin composition in which a solvent is added to adjust the solid content (non-volatile content) to 40% is, for example, preferably 30 mPa s or less, more preferably 20 mPa s or less, and 15 mPa s or less. is particularly preferred. The lower limit of the viscosity is preferably, for example, 1 mPa·s or more, more preferably 5 mPa·s or more, depending on the desired thickness of the cured film. By setting the viscosity within the above range, the handleability and coating workability are improved.

In addition to the components described above, the photosensitive resin composition of the present invention includes fillers such as aluminum hydroxide, talc, clay, and barium sulfate, quantum dot particles, and colorants, as long as the effects of the present invention are not impaired. (pigments, dyes), antifoaming agents, coupling agents, leveling agents, sensitizers, release agents, lubricants, plasticizers, antioxidants, UV absorbers, light stabilizers, flame retardants, polymerization inhibitors, polymerization Known additives such as retarders, polymerization accelerators, thickeners, dispersants and surfactants may be contained. As the pigment, one or more of various organic or inorganic colorants can be used. Dyes, organic pigments, natural pigments, and the like can be used as organic colorants.
Coloring materials are described below.
Examples of the coloring material include pigments and dyes. As the coloring material, either a pigment or a dye may be used, or a combination of the pigment and the dye may be used. For example, when forming red, blue, and green pixels of a color filter, it is preferable to use a known technique that achieves desired color characteristics by appropriately combining color materials such as blue and purple, green and yellow, and the like. Also, when forming a black matrix or a black column spacer, it is preferable to use a black coloring material.
Among the coloring materials, pigments are preferred from the standpoint of durability, and dyes are preferred from the standpoint of improving the luminance of panels and the like. These can be appropriately selected according to the properties required. In the curable resin composition of the present invention, pigments are preferred because they can further improve the solvent resistance and heat-resistant coloring resistance of the cured product. Pigments similar to those described in JP-A-2015-157909 can be used.
Examples of the dye include organic dyes described in JP-A-2010-9033, JP-A-2010-211198, JP-A-2009-51896, and JP-A-2008-50599. can. Among them, azo dyes, anthraquinone dyes, phthalocyanine dyes, quinoneimine dyes, quinoline dyes, nitro dyes, carbonyl dyes, methine dyes and the like are preferable.
These colorants may be used singly or in combination of two or more.
The content ratio of the coloring material is not particularly limited, and can be appropriately set according to the purpose and application. 80 mass %, more preferably 5 to 70 mass %, still more preferably 10 to 60 mass %. Moreover, when the photosensitive resin composition of the present invention contains the coloring material, it preferably further contains a dispersant. The dispersant has a site for interaction with the colorant and a site for interaction with the dispersion medium (for example, solvent or binder resin), and has the function of stabilizing the dispersion of the colorant in the dispersion medium. They are generally classified into resin-type dispersants (eg, polymer dispersants), surfactants (eg, low-molecular-weight dispersants), and pigment derivatives. These may be used individually by 1 type, and may be used in combination of 2 or more type.
Examples of the resin-type dispersant include polyurethanes, polycarboxylic acid esters such as polyacrylates, unsaturated polyamides, polycarboxylic acids, polycarboxylic acid amine salts, polycarboxylic acid ammonium salts, polycarboxylic acid alkylamine salts, and polysiloxanes. , long-chain polyaminoamide phosphates, hydrogen group-containing polycarboxylic acid esters, amides and salts thereof formed by the reaction of poly(lower alkyleneimine) with polyesters having free carboxyl groups, (meth)acrylic acid-styrene copolymers, (meth)acrylic acid-(meth)acrylic acid ester copolymers, styrene-maleic acid copolymers, polyvinyl alcohol, polyvinylpyrrolidone, polyesters, modified polyacrylates, ethylene oxide/polypropylene oxide adducts, etc. mentioned. Commercially available products of the resin-type dispersant include those described in JP-A-2015-157909.
Examples of the surfactant include polyoxyethylene alkyl ether sulfate, sodium dodecylbenzenesulfonate, sodium alkylnaphthalenesulfonate, sodium alkyldiphenyl ether disulfonate, monoethanolamine lauryl sulfate, triethanolamine lauryl sulfate, ammonium lauryl sulfate, Anionic surfactants such as sodium stearate and sodium lauryl sulfate; nonions such as polyoxyethylene oleyl ether, polyoxyethylene lauryl ether, polyoxyethylene nonylphenyl ether, polyoxyethylene sorbitan monostearate, and polyethylene glycol monolaurate cationic surfactants such as alkyl quaternary ammonium salts and their ethylene oxide adducts; amphoteric surfactants such as alkylbetaines such as alkyldimethylaminoacetic acid betaine and alkylimidazoline;
The dye derivative is a compound having a structure in which a functional group is introduced into the dye. Examples of the functional group include a sulfonic acid group, a sulfonamide group and quaternary salts thereof, a dialkylamino group, a hydroxyl group, a carboxyl group, and an amide group. , a phthalimide group, and the like. Examples of the structure of the base dye include azo, anthraquinone, quinophthalone, phthalocyanine, quinacridone, benzimidazolone, isoindoline, dioxazine, indanthrene, perylene, and diketopyrrolopyrroles. system and the like.
The content of the dispersant may be appropriately set according to the purpose and application. It is preferably 0.01 to 60% by mass with respect to 100% by mass of the total solid content of the resin composition. More preferably 0.1 to 50% by mass, still more preferably 0.3 to 40% by mass.
The method for preparing the photosensitive resin composition is not particularly limited, and a known method may be used. For example, a method of mixing and dispersing each of the above-described components using various mixers or dispersers may be mentioned. be done. The mixing/dispersing step is not particularly limited, and may be performed by a known method. In addition, other steps that are normally performed may be further included. When the photosensitive resin composition contains a colorant, it is preferably prepared through a colorant dispersion treatment step.
As the above-described colorant dispersion treatment step, for example, first, predetermined amounts of a colorant (preferably an organic pigment), a dispersant, and a solvent are weighed, and the colorant is finely dispersed using a disperser to obtain a liquid colorant. Methods of obtaining dispersions (also referred to as "millbases") are included. Examples of the dispersing machine include paint conditioners, bead mills, roll mills, ball mills, jet mills, homogenizers, kneaders and blenders. As the dispersion treatment step, preferably, after kneading and dispersing with a roll mill, a kneader, a blender, etc., fine dispersion treatment is performed with a media mill such as a bead mill filled with beads of 0.01 to 1 mm. . To the obtained mill base, a composition (preferably a transparent liquid) containing the radical polymerizable polymer, inorganic fine particles, etc., which has been separately stirred and mixed, is added and mixed to form a uniform dispersion solution, and the photosensitive resin composition is added. Obtainable. The obtained photosensitive resin composition is preferably filtered using a filter or the like to remove fine dust.

The present invention also provides a cured film obtained by curing the above radically polymerizable polymer and/or the above photosensitive resin composition. Examples of materials used as substrates to be coated include transparent materials such as glass, acrylic resins, polycarbonate resins, polyester resins such as PET, polystyrene resins, and metal materials such as aluminum, copper, iron, and stainless steel. The cured film preferably has a film thickness (thickness) of 0.1 to 20 μm. As a result, it is possible to satisfactorily meet the demand for reduction in the height of members, display devices, and the like using the cured film. More preferably 0.5 to 10 μm, still more preferably 0.5 to 8 μm.
Specifically, the light transmittance of the cured film can be 65% or more, preferably 70% or more, more preferably 75% or more, at a thickness of 130 μm for light with a wavelength of 410 nm. is preferred. Thus, the cured film obtained from the photosensitive resin composition of the present invention preferably has high transparency. As a result, for example, even when a laminate including a cured film is used for a touch panel, a clear image can be displayed without deteriorating the display performance of the touch panel.
A color filter having a cured product (cured film) of the above photosensitive resin composition on a substrate is also one aspect of the present invention. The color filters are described below.
The color filter of the present invention is in the form of having a cured product of the above photosensitive resin composition on a substrate. In the above-mentioned color filter, the cured product formed from the above-mentioned photosensitive resin composition is particularly suitable as, for example, a black matrix or a segment that requires coloring such as each pixel of red, green, blue, yellow, etc. , photospacers, protective layers, alignment control ribs, and other segments that do not necessarily require coloring.
Examples of the substrate used in the color filter include glass substrates such as white plate glass, soda plate glass, alkali-strengthened glass, silica-coated soda plate glass; Sheets, films or substrates made of thermoplastic resins such as additives; Sheets, films or substrates made of thermosetting resins such as epoxy resins and unsaturated polyester resins; Metal substrates such as aluminum plates, copper plates, nickel plates and stainless steel plates a ceramic substrate; a semiconductor substrate having a photoelectric conversion element; a member composed of various materials such as a glass substrate having a coloring material layer on its surface (for example, a color filter for LCD); Among them, a glass substrate and a sheet, film or substrate made of a heat-resistant resin are preferable from the viewpoint of heat resistance. Also, the substrate is preferably a transparent substrate. If necessary, the substrate may be subjected to corona discharge treatment, ozone treatment, chemical treatment using a silane coupling agent or the like.
In order to obtain the color filter, for example, for each pixel color (that is, for each pixel of one color), a step of disposing the photosensitive resin composition on a substrate (also referred to as an disposing step), and disposing on the substrate a step of irradiating the obtained photosensitive resin composition with light (also referred to as a light irradiation step), a step of developing with a developer (also referred to as a developing step), and a step of heat-treating (also referred to as a heating step). It is preferable to employ a manufacturing method that employs a technique and repeats the same technique for each color. Note that the order in which the pixels of each color are formed is not particularly limited.
The placement step is preferably performed by coating. Examples of the method for applying the photosensitive resin composition on the substrate include spin coating, slit coating, roll coating, casting coating, and the like. Since the photosensitive resin composition of the present invention can be adjusted in a suitable range of viscosity and is excellent in coating workability, any method can be preferably used.
The heating step is finally a step of further curing the exposed portion (cured portion) by baking (also referred to as a post-curing step). For example, using a light source such as a high-pressure mercury lamp, a step of post-exposure with a light amount of, for example, 0.5 to 5 J/cm ² , a step of post-heating, for example, at a temperature of 60 to 260° C. for 10 seconds to 120 minutes, etc. mentioned. By performing such a post-curing step, it is possible to further increase the hardness and adhesion of the patterned cured film.
As described above, the radically polymerizable polymer of the present invention is easy to handle, excellent in coating workability, and can give a cured product excellent in transparency and adhesion. Moreover, the photosensitive resin composition containing the radically polymerizable polymer of the present invention is further excellent in curability, and can give a cured product excellent in adhesiveness to substrates, transparency, heat resistance, and the like. Such radically polymerizable polymer and photosensitive resin composition of the present invention can be used for applications such as resist materials, various coating agents, and paints. It can be suitably used as an alkali-developable negative resist material for producing colored pixels of filters, black matrixes, overcoats, photospacers, optical waveguides, and the like.

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.
The present invention will be concretely illustrated by examples, comparative examples, and characteristic evaluations. In the examples and comparative examples, unless otherwise specified, % and wt% mean % by mass, and parts mean parts by mass.
In the following production examples, etc., various physical properties were evaluated as follows.
[Evaluation method]
(1) weight average molecular weight (Mw)
Measurement was performed by GPC (HLC-8220GPC, manufactured by Tosoh Corporation) using THF as an eluent, using TSKgel SuperHZM-N (manufactured by Tosoh Corporation) as a column, and calculated in terms of standard polystyrene.
(2) Solid Content About 0.3 g of the copolymer solution prepared in Production Example was weighed into an aluminum cup, and about 1 g of acetone was added to dissolve the solution, followed by natural drying at room temperature. Then, using a hot air dryer (trade name: PHH-101, manufactured by ESPEC Co., Ltd.), it was dried at 140° C. for 3 hours, allowed to cool in a desiccator, and weighed. The weight of the solid content (resin) of the polymer solution was calculated from the amount of weight loss.
(3) Acid value 1.5 g of the copolymer solution prepared in Production Example was precisely weighed, dissolved in a mixed solvent of 90 g of acetone and 10 g of water, and titrated with a 0.1N KOH aqueous solution. Titration was performed using an automatic titrator (trade name: COM-555, manufactured by Hiranuma Sangyo Co., Ltd.), and the acid value per 1 g of polymer was obtained from the solid content concentration (mgKOH/g).

(4) Glass transition temperature (Tg)
In this example, the glass transition temperature (Tg) of each polymer was calculated. The calculation method conforms to the following FOX formula.
1/(Tg+273)=Σ[wi/(Tgi+273)]
(In the formula, wi is the mass ratio of the monomer i, and Tgi is the glass transition temperature (° C.) of the homopolymer of the monomer i).
The Tg of the homopolymer of the monomers used in the FOX formula is, for example, described in "POLYMER HANDBOOK THIRD EDITION" (J. BRANDRUP, E. H. IMMERGUT, 1989, published by John Wiley & Sons, Inc., page: VI /209 to VI/277) (if multiple glass transition temperatures are listed, the lowest value) may be adopted. Further, for monomers not listed in "POLYMER HANDBOOK THIRD EDITION", commercially available glass transition temperature calculation software (e.g., Accelrys Software Inc. "MATERIALS STUDIO", version: 4.0.0.0, module : Synthia, condition: calculated with a polymerization average molecular weight of 100,000).
Specifically, the copolymer Tg of the present invention is calculated from the following formula.
₁ /(Tg ₊ 273)=w1 _/ (Tg1 ₊ 273)+w2/(Tg2+273)+...
Tg: Copolymer Tg
(w _1, w _{2, ...} : weight fractions of monomers 1, 2, ... in the copolymer Tg _1, Tg _{2, ...} : monomer 1 constituting the copolymer , 2, ... homopolymer Tg)
In the case of actual measurement, the polymer solution was applied to a 5 cm square glass substrate, spin-coated onto the glass substrate, and dried at room temperature under reduced pressure for 4 hours to form a thin film with a film mass of 30 mg or less. Volatile components are removed to obtain a solid content. Regarding the solid content, it is confirmed by quantification by gas chromatography that the residual solvent is 0.1 wt % or less. The obtained solid content is measured using a DSC (differential scanning calorimeter method, measuring instrument: Netch DSC3500) in accordance with JIS-K7121 at a heating rate of 10° C./min under a nitrogen stream.

[Production of radically polymerizable polymer]
The following radically polymerizable polymer was used.
[Production Example 1]
A separable flask equipped with a cooling tube was prepared as a reactor. On the other hand, in the monomer dropping tank, 20 g of N-phenylmaleimide (PMI), 36 g of methacrylic acid (MAA), 44 g of lauryl methacrylate (LMA), t-butylperoxy-2-ethylhexanoate ( 8 g of trade name "PERBUTYL (registered trademark) O" manufactured by NOF CORPORATION, hereinafter also referred to as PBO) was added and mixed with stirring.

A reactor was charged with 233 g of propylene glycol methyl ether acetate (PGMEA) and purged with nitrogen. After the temperature of the reactor was stabilized at 90° C., the monomer composition was added dropwise. While maintaining the temperature at 90° C., the monomer composition was added dropwise over 180 minutes. After the dropping of the monomer composition was completed, 0.5 g of PBO was added. After an additional 30 minutes, the bath was heated to 115°C. After maintaining the temperature at 115° C. for 1 hour, a gas introduction tube was attached to the separable flask, and bubbling of a mixed gas of oxygen/nitrogen=7/93 (v/v) was started. Next, in the reactor, 20.5 g of Cychromer M100 (manufactured by Daicel, hereinafter M100), 0.2 g of Antage W-400 (manufactured by Kawaguchi Chemical Industry Co., Ltd.) as a polymerization inhibitor, and 0.4 g of triphenylphosphine (TPP) as a catalyst were added. It was charged and reacted at 115° C. for 14 hours. Thereafter, the mixture was cooled to room temperature to obtain a copolymer solution (A-1) containing 34.2% by weight of resin. The resin had a weight average molecular weight (Mw) of 8000 and an acid value of 150 mgKOH/g. Table 1 shows the production conditions, solid content concentration (non-volatile content), weight average molecular weight (Mw) and acid value of the copolymer solution.
[Production Example 2]
A separable flask equipped with a cooling tube was prepared as a reactor. On the other hand, 20 g of N-benzylmaleimide (BzMI), 31 g of acrylic acid (AA), 17 g of LMA, 32 g of methyl methacrylate (MMA), and 6 g of PBO were charged as a monomer composition into the monomer dropping tank and mixed with stirring.

After charging 233 g of PGMEA into the reactor and purging with nitrogen, the temperature of the reactor was raised to 90° C. by heating with an oil bath while stirring. After the temperature of the reactor was stabilized at 90° C., the monomer composition was added dropwise. While maintaining the temperature at 90° C., the monomer composition was added dropwise over 180 minutes. After the dropping of the monomer composition was completed, 0.5 g of PBO was added. After an additional 30 minutes, the bath was heated to 115°C. After maintaining the temperature at 115° C. for 1 hour, a gas introduction tube was attached to the separable flask, and bubbling of a mixed gas of oxygen/nitrogen=7/93 (v/v) was started. Then, 33 g of glycidyl methacrylate (GMA), 0.2 g of Antage W-400 as a polymerization inhibitor, and 0.4 g of TPP as a catalyst were charged into the reactor and reacted at 115° C. for 14 hours. Thereafter, the mixture was cooled to room temperature to obtain a copolymer solution (A-2) containing 36.1% by weight of resin. The resin had a weight average molecular weight (Mw) of 12000 and an acid value of 76 mgKOH/g. Table 1 shows the production conditions, solid content concentration (non-volatile content), weight average molecular weight (Mw) and acid value of the copolymer solution.
[Production Example 3]
A separable flask equipped with a cooling tube was prepared as a reactor. On the other hand, 15 g of PMI, 31 g of AA, 54 g of n-octyl acrylate (NOAA), and 10 g of PBO were added as a monomer composition into a monomer dropping tank and stirred and mixed.

After charging 233 g of PGMEA into the reactor and purging with nitrogen, the temperature of the reactor was raised to 90° C. by heating with an oil bath while stirring. After the temperature of the reactor was stabilized at 90° C., the monomer composition was added dropwise. While maintaining the temperature at 90° C., the monomer composition was added dropwise over 180 minutes. After the dropping of the monomer composition was completed, 0.5 g of PBO was added. After an additional 30 minutes, the bath was heated to 115°C. After maintaining the temperature at 115° C. for 1 hour, a gas introduction tube was attached to the separable flask, and bubbling of a mixed gas of oxygen/nitrogen=7/93 (v/v) was started. Then, 33 g of GMA, 0.2 g of Antage W-400 as a polymerization inhibitor, and 0.4 g of TPP as a catalyst were charged into the reactor and reacted at 115° C. for 14 hours. Thereafter, the mixture was cooled to room temperature to obtain a copolymer solution (A-3) containing 36.3% by weight of resin. The resin had a weight average molecular weight (Mw) of 7000 and an acid value of 77 mgKOH/g. Table 1 shows the production conditions, solid content concentration (nonvolatile content), weight average molecular weight (Mw) and acid value of the copolymer solution.
[Production Example 4]
A separable flask with a cooling tube was prepared as a reactor. On the other hand, 15 g of PMI, 31 g of AA, 54 g of 2-ethylhexyl acrylate (2EHA), and 10 g of PBO were charged as a monomer composition into the monomer dropping tank and mixed with stirring.

After charging 233 g of PGMEA into the reactor and purging with nitrogen, the temperature of the reactor was raised to 90° C. by heating with an oil bath while stirring. After the temperature of the reactor was stabilized at 90° C., the monomer composition was added dropwise. While maintaining the temperature at 90° C., the monomer composition was added dropwise over 180 minutes. After the dropping of the monomer composition was completed, 0.5 g of PBO was added. After an additional 30 minutes, the bath was heated to 115°C. After maintaining the temperature at 115° C. for 1 hour, a gas introduction tube was attached to the separable flask, and bubbling of a mixed gas of oxygen/nitrogen=7/93 (v/v) was started. Then, 33 g of GMA, 0.2 g of Antage W-400 as a polymerization inhibitor, and 0.4 g of TPP as a catalyst were charged into the reactor and reacted at 115° C. for 14 hours. Thereafter, the mixture was cooled to room temperature to obtain a copolymer solution (A-4) containing 36.1% by weight of resin. The resin had a weight average molecular weight (Mw) of 6500 and an acid value of 78 mgKOH/g. Table 1 shows the production conditions, solid content concentration (non-volatile content), weight average molecular weight (Mw) and acid value of the copolymer solution.
[Production Example 5]
A separable flask equipped with a cooling tube was prepared as a reactor. On the other hand, 15 g of methyl (α-allyloxymethyl)acrylate (AOMA), 44 g of AA, 41 g of LMA, and 16 g of PBO were put into the monomer dropping tank and mixed with stirring.

After charging 233 g of PGMEA into the reactor and purging with nitrogen, the temperature of the reactor was raised to 90° C. by heating with an oil bath while stirring. After the temperature of the reactor was stabilized at 90° C., the monomer composition was added dropwise. While maintaining the temperature at 90° C., the monomer composition was added dropwise over 180 minutes. After the dropping of the monomer composition was completed, 0.5 g of PBO was added. After an additional 30 minutes, the bath was heated to 115°C. After maintaining the temperature at 115° C. for 1 hour, a gas introduction tube was attached to the separable flask, and bubbling of a mixed gas of oxygen/nitrogen=7/93 (v/v) was started. Then, 69 g of GMA, 0.2 g of Antage W-400 as a polymerization inhibitor, and 0.4 g of TPP as a catalyst were charged into the reactor and reacted at 115° C. for 21 hours. Thereafter, the mixture was cooled to room temperature to obtain a copolymer solution (A-5) containing 41.9% by weight of resin. The resin had a weight average molecular weight (Mw) of 9000 and an acid value of 50 mgKOH/g. Table 1 shows the production conditions, solid content concentration (non-volatile content), weight average molecular weight (Mw) and acid value of the copolymer solution.
[Production Example 6]
A separable flask equipped with a cooling tube was prepared as a reactor. On the other hand, 37 g of MAA, 50 g of styrene (St), 13 g of MMA, and 10 g of PBO were charged as a monomer composition into a monomer dropping tank and mixed with stirring.

After charging 233 g of PGMEA into the reactor and purging with nitrogen, the temperature of the reactor was raised to 90° C. by heating with an oil bath while stirring. After the temperature of the reactor was stabilized at 90° C., the monomer composition was added dropwise. While maintaining the temperature at 90° C., the monomer composition was added dropwise over 180 minutes. After the dropping of the monomer composition was completed, 0.5 g of PBO was added. After an additional 30 minutes, the bath was heated to 115°C. After maintaining the temperature at 115° C. for 1 hour, a gas introduction tube was attached to the separable flask, and bubbling of a mixed gas of oxygen/nitrogen=7/93 (v/v) was started. Then, 54.4 g of M100, 0.2 g of Antage W-400 as a polymerization inhibitor, and 0.4 g of TPP as a catalyst were charged into the reactor and reacted at 115° C. for 21 hours. Then, it was cooled to room temperature to obtain a copolymer solution (A-6) containing 39.5% by weight of resin. The resin had a weight average molecular weight (Mw) of 7000 and an acid value of 90 mgKOH/g. Table 1 shows the production conditions, solid content concentration (non-volatile content), weight average molecular weight (Mw) and acid value of the copolymer solution.
[Production Example 7]
A separable flask equipped with a cooling tube was prepared as a reactor. On the other hand, 20 g of BzMI, 31 g of AA, 17 g of St, 32 g of MMA, and 6 g of PBO were charged as a monomer composition into the monomer dropping tank and stirred and mixed.

After 233 g of PGMEA was introduced into the reaction vessel and purged with nitrogen, the temperature of the reaction vessel was raised to 90° C. by heating with an oil bath while stirring. After the temperature of the reactor was stabilized at 90° C., the monomer composition was added dropwise. While maintaining the temperature at 90° C., the monomer composition was added dropwise over 180 minutes. After the dropping of the monomer composition was completed, 0.5 g of PBO was added. After an additional 30 minutes, the bath was heated to 115°C. After maintaining the temperature at 115° C. for 1 hour, a gas introduction tube was attached to the separable flask, and bubbling of a mixed gas of oxygen/nitrogen=7/93 (v/v) was started. Then, 33 g of GMA, 0.2 g of Antage W-400 as a polymerization inhibitor, and 0.4 g of TPP as a catalyst were charged into the reactor and reacted at 115° C. for 14 hours. Then, it was cooled to room temperature to obtain a copolymer solution (A-7) containing 36.6% by weight of resin. The resin had a weight average molecular weight (Mw) of 15000 and an acid value of 76 mgKOH/g. Table 1 shows the production conditions, solid content concentration (non-volatile content), weight average molecular weight (Mw) and acid value of the copolymer solution.
[Production Example 8]
A separable flask equipped with a cooling tube was prepared as a reactor. On the other hand, 15 g of AOMA, 15 g of MAA, 47 g of 2EHA, 23 g of MMA, and 8 g of PBO were put into the monomer dropping tank and mixed with stirring.

After 233 g of PGMEA was introduced into the reaction vessel and purged with nitrogen, the temperature of the reaction vessel was raised to 90° C. by heating with an oil bath while stirring. After the temperature of the reactor was stabilized at 90° C., the monomer composition was added dropwise. While maintaining the temperature at 90° C., the monomer composition was added dropwise over 180 minutes. After the dropping of the monomer composition was completed, 0.5 g of PBO was added. After an additional 30 minutes, the bath was heated to 115°C. After maintaining the temperature at 115° C. for 1 hour, it was cooled to room temperature to obtain a copolymer solution (A-8) containing 30.3% by weight of resin. The resin had a weight average molecular weight (Mw) of 6500 and an acid value of 100 mgKOH/g. Table 1 shows the production conditions, solid content concentration (non-volatile content), weight average molecular weight (Mw) and acid value of the copolymer solution.
Table 1 shows the compositions and physical properties of A-1 to A-5 (Examples 1 to 5) and A-6 to A-8 (Comparative Examples 1 to 3) of the above radically polymerizable polymers.

［感光性樹脂組成物の調製］
バインダー樹脂として上記共重合体溶液（Ａ－１）３．５１ｇ（すなわち、樹脂１．２ｇ）、無機微粒子（シリカ微粒子）としてＰＧＭ－ＡＣ－4130Ｙ ４．００ｇ（不揮発分１．２ｇ：日産化学製）、多官能モノマーとしてＤＰＨＡ１．５４ｇ、および光重合開始剤として２－メチル－１－[４－（メチルチオ）フェニル]－２－モルホリノ－プロパン－１－オン（商品名「ＩＲＧＡＣＵＲＥ（登録商標）907」、ＢＡＳＦジャパン社製、以下Ｉｒｇ907と表す）０．０６ｇを加え、不揮発分濃度が４０重量％となるようにＰＧＭＥＡで希釈し、感光性樹脂組成物Ｂ１を調製した。
同様にバインダー樹脂として上記共重合体溶液（Ａ－２～８）を用いて感光性樹脂組成物Ｂ２～８を調製した。感光性樹脂組成物Ｂ１～Ｂ５（実施例６～１０）、感光性樹脂組成物Ｂ６～Ｂ８（比較例４～６）の組成及び評価結果を表２に記す。
樹脂組成物Ｂの２５℃での粘度をコーンプレート型回転粘度計（ＴＶＥ２２ＬＴ、東機産業製）により測定した。なお、コーンプレートは標準ロータ（名称：1°３４´×R２４）を用いた。
（硬化方法）
５ｃｍ角のガラス基板上に、上記感光性樹脂組成物Ｂ１～１０をスピンコーターにより塗布し、オーブンで８０℃３分間乾燥した。乾燥後、２．０ｋＷの超高圧水銀ランプを装着したＵＶアライナ（商品名「ＴＭＥ－１５０ＲＮＳ」、ＴＯＰＣＯＮ社製）によって１Ｊ／ｃｍ^２の強度（３６５ｎｍ照度換算）で紫外線を照射した。紫外線照射後、１６０℃で1時間アフターキュアーを行い塗膜を完全に硬化させた。得られた塗膜を下記評価（５）、（６）に供した。結果を表２に示す。
（５）密着性（クロスカット試験）
ＪＩＳ Ｋ５６００－５－６：１９９９「塗料一般試験方法－第５部：塗膜の機械的性質－第６節：付着性（クロスカット法）」を行った結果の残膜存率が１００～９０％の場合に１、８９～８０％の場合に２、７９～７０％の場合に３、６９～６０％の場合に４、５９％未満の場合に５とした。評価結果を表２に示す。
（６）透過率
ガラス基板をブランクとして用い、塗膜の光線透過率を分光光度計ＵＶ３１００（島津製作所社製）で測定し、410ｎｍの透過率を求めた。

[Preparation of photosensitive resin composition]
3.51 g of the above copolymer solution (A-1) as a binder resin (that is, 1.2 g of resin), 4.00 g of PGM-AC-4130Y as inorganic fine particles (silica fine particles) (1.2 g of nonvolatile content: manufactured by Nissan Chemical Industries, Ltd. ), 1.54 g of DPHA as a polyfunctional monomer, and 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-propan-1-one as a photoinitiator (trade name “IRGACURE® 907 , manufactured by BASF Japan Ltd., hereinafter referred to as Irg907) was added and diluted with PGMEA so that the non-volatile content concentration was 40% by weight, to prepare a photosensitive resin composition B1.
Similarly, photosensitive resin compositions B2-8 were prepared using the above copolymer solutions (A-2-8) as binder resins. Table 2 shows the compositions and evaluation results of the photosensitive resin compositions B1 to B5 (Examples 6 to 10) and the photosensitive resin compositions B6 to B8 (Comparative Examples 4 to 6).
The viscosity of Resin Composition B at 25° C. was measured with a cone-plate rotational viscometer (TVE22LT, manufactured by Toki Sangyo). A standard rotor (name: 1°34′×R24) was used for the cone plate.
(Curing method)
The above photosensitive resin compositions B1 to B10 were applied onto a 5 cm square glass substrate using a spin coater and dried in an oven at 80° C. for 3 minutes. After drying, it was irradiated with ultraviolet rays at an intensity of 1 J/cm ² (365 nm illuminance conversion) by a UV aligner (trade name “TME-150RNS”, manufactured by TOPCON) equipped with a 2.0 kW ultra-high pressure mercury lamp. After UV irradiation, after-curing was performed at 160° C. for 1 hour to completely cure the coating film. The obtained coating film was subjected to the following evaluations (5) and (6). Table 2 shows the results.
(5) Adhesion (cross-cut test)
JIS K5600-5-6: 1999 "Paint general test method-Part 5: Mechanical properties of coating film-Section 6: Adhesion (cross-cut method)" Residual film survival rate is 100 to 90 %, 2 when 89-80%, 3 when 79-70%, 4 when 69-60%, and 5 when less than 59%. Table 2 shows the evaluation results.
(6) Transmittance Using a glass substrate as a blank, the light transmittance of the coating film was measured with a spectrophotometer UV3100 (manufactured by Shimadzu Corporation) to determine the transmittance at 410 nm.

略称は下記のとおりである。
Ｉｒｇ９０７：ＩＲＧＡＣＵＲＥ（登録商標）９０７、２－メチル－１－［４－（メチルチオ）フェニル］－２－モルフォリノプロパン－１－オン
ＤＰＨＡ：ジペンタエリスリトールヘキサアクリレート
表１及び２より、以下の事項を確認した。
製造例１～５で得られた共重合体Ａ－１～Ａ－５は、本発明のラジカル重合性重合体に該当する。一方製造例６で得た共重合体Ａ－６は、主鎖に環構造を有する構造単位及び一般式（１）で表される構造単位を含まず、一般式（２）で表される構造単位が５質量％超である点で、製造例７で得た共重合体Ａ－７は、上記一般式（１）で表される構造単位を含まず、重量平均分子量が１４０００超、且つ一般式（２）で表される構造単位が５質量％超である点で、製造例８で得た共重合体Ａ－８は重合性二重結合（炭素－炭素二重結合）を有していない点で、共重合体Ａ－１～Ａ－５とは相違する。
このような相違のもと無機微粒子と併用した感光性樹脂組成物での粘度、透明性（光線透過率）及び密着性を比べると、共重合体Ａ－６～Ａ－８を用いた比較例４～比較例６に対し、共重合体Ａ－１～Ａ－５を用いた実施例６～１０では、粘度が低く、光線透過率が高いことが分かった。なお、スチレンを高い割合で共重合しているＡ－６を含む樹脂組成物Ｂ６は、Ｂ１～Ｂ５に比べて４１０ｎｍ透過率が低く、硬化膜の透明性が低いことから、一般式（２）で表される構造単位の含有割合が少ないことの効果を確認できた。（表２参照）。また比較例４及び比較例６に対し、共重合体Ａ－１～Ａ－５を用いた実施例６～１０では、密着性が良好であることが分かった（表２参照）。なお、密着性の発現には主鎖環構造、及び側鎖のエチレン性不飽和二重結合量が特定範囲の重合体を含むことが効いていると考えられる。またＭ１００よりもＧＭＡ付加による側鎖二重結合が好適であった。
その他、一般式（１）で表される構造単位の炭化水素基として分岐している２ＥＨＡを共重合しているＡ－４を含む実施例９よりも、直鎖のＮＯＡＡやＬＭＡを共重合しているＡ－１～Ａ－３を含む実施例６～８の方が、やや低粘度で塗布作業性が良好で、４１０ｎｍ透過率が高い傾向であった。
以上より、本発明のラジカル重合性重合体、感光性樹脂組成物の優位性が認められた。

Abbreviations are as follows.
Irg907: IRGACURE® 907, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one DPHA: dipentaerythritol hexaacrylate From Tables 1 and 2, the following confirmed.
Copolymers A-1 to A-5 obtained in Production Examples 1 to 5 correspond to the radically polymerizable polymer of the present invention. On the other hand, the copolymer A-6 obtained in Production Example 6 does not contain a structural unit having a ring structure in the main chain and a structural unit represented by general formula (1), and has a structure represented by general formula (2) Copolymer A-7 obtained in Production Example 7 does not contain the structural unit represented by the general formula (1), has a weight average molecular weight of more than 14000, and is generally Copolymer A-8 obtained in Production Example 8 has a polymerizable double bond (carbon-carbon double bond) in that the structural unit represented by formula (2) is more than 5% by mass. It is different from the copolymers A-1 to A-5 in that there is no
When comparing the viscosity, transparency (light transmittance) and adhesion of the photosensitive resin composition used in combination with inorganic fine particles under such a difference, comparative examples using copolymers A-6 to A-8 In contrast to Examples 4 to Comparative Examples 4 to 6, Examples 6 to 10 using copolymers A-1 to A-5 were found to have low viscosities and high light transmittances. In addition, the resin composition B6 containing A-6, which is copolymerized with a high proportion of styrene, has a lower 410 nm transmittance than B1 to B5, and the transparency of the cured film is low. It was possible to confirm the effect of having a small content ratio of the structural unit represented by. (See Table 2). In addition, in comparison with Comparative Examples 4 and 6, it was found that Examples 6 to 10 using copolymers A-1 to A-5 had good adhesion (see Table 2). In addition, it is considered that inclusion of a polymer having a main chain ring structure and a side chain ethylenically unsaturated double bond content within a specific range is effective for expression of adhesiveness. Moreover, the side chain double bond by addition of GMA was more suitable than M100.
In addition, linear NOAA and LMA are copolymerized rather than Example 9 including A-4 in which branched 2EHA is copolymerized as the hydrocarbon group of the structural unit represented by general formula (1). Examples 6 to 8, including A-1 to A-3, tended to have a slightly lower viscosity, better coating workability, and higher 410 nm transmittance.
From the above, the superiority of the radically polymerizable polymer and the photosensitive resin composition of the present invention was recognized.

The radically polymerizable polymer and photosensitive resin composition of the present invention can be applied, for example, to resist materials, and can be suitably used in the fields of optics, electrical machinery and electronics.

Claims (7)

A radically polymerizable polymer having an acid group and an ethylenically unsaturated double bond in a side chain,
The radically polymerizable polymer has a structural unit having a ring structure in its main chain and a structural unit represented by the following general formula (1),
The double bond equivalent is 330 to 1600 (g / equivalent),
weight average molecular weight is 14000 or less,
The content ratio of the structural unit represented by the following general formula (2) is 5% by mass or less with respect to 100% by mass of the total structural units of the radically polymerizable polymer,
A radically polymerizable polymer, wherein the acid group has 6 or less atoms spaced from the main chain.

(In the formula, R ¹ represents a hydrogen atom or a methyl group. R ² represents a linear or branched hydrocarbon group having 6 to 20 carbon atoms.)

( ^In the formula, R3 represents a hydrogen atom or a methyl group.) 2. The radically polymerizable polymer according to claim 1, which has an acid value of 50 to 150 (mgKOH/g). 3. The method according to claim 1, wherein the content of the structural unit represented by the general formula (1) is 10% by mass or more with respect to 100% by mass of the total structural units of the radically polymerizable polymer. A radically polymerizable polymer as described. 4. The radically polymerizable polymer according to any one of claims 1 to 3, wherein the acid group is a carboxyl group derived from (meth)acrylic acid. 5. The radically polymerizable polymer according to any one of claims 1 to 4, which has a glass transition temperature of 50°C or lower. A photosensitive resin composition comprising the radically polymerizable polymer according to any one of claims 1 to 5 and a polyfunctional monomer. 7. The photosensitive resin composition according to claim 6, further comprising a photopolymerization initiator, inorganic fine particles and a solvent.