JP5772181B2 - Radiation sensitive resin composition, interlayer insulating film for display element and method for forming the same - Google Patents

Description

  The present invention relates to a radiation-sensitive resin composition, an interlayer insulating film for display elements, and a method for forming the same.

  The display element is generally provided with a display element interlayer insulating film for the purpose of insulating between wirings arranged in layers. As a material for forming an interlayer insulating film for a display element, the number of processes for obtaining a necessary pattern shape is small, and since a high level of flatness is required for the obtained interlayer insulating film for a display element, a radiation-sensitive resin composition Is widely used. Such a radiation sensitive resin composition is required to have good sensitivity, and the interlayer insulating film for display elements is required to have excellent surface hardness, solvent resistance, etc. in addition to the above flatness.

  As such a radiation sensitive resin composition, an acrylic resin is widely adopted, and for example, a composition containing a crosslinking agent, an acid generator and an alkali-soluble resin is known (Japanese Patent Application Laid-Open No. 2004-4669). Issue gazette). The alkali-soluble resin refers to a resin having a protecting group (a group that is insoluble or hardly soluble in an alkaline aqueous solution and can be dissociated by the action of an acid) and becomes soluble in an alkaline aqueous solution after the protective group is dissociated. . As another radiation-sensitive resin composition, a radiation-sensitive resin composition containing an acetal structure and / or a ketal structure, a resin containing an epoxy group, and an acid generator has been proposed (Japanese Patent Application Laid-Open No. 2004-2004). 264623).

  However, when an attempt is made to form an interlayer insulating film for a display element using a conventional radiation-sensitive resin composition having a protective group, the protective film dissociated by exposure is discharged out of the resist film. There is a disadvantage that the reduction occurs and the flatness of the interlayer insulating film for display elements is impaired. In order to avoid this inconvenience, it is necessary to increase the coating amount of the radiation sensitive resin composition on the assumption of film reduction in advance, which is disadvantageous in terms of cost. Further, in the case of a liquid crystal display, when such a phenomenon occurs in a liquid crystal cell, a protective group may be mixed in the liquid crystal, which may cause display defects.

  In view of such circumstances, the radiation-sensitive resin composition has good sensitivity, has excellent flatness (residual film ratio) in addition to surface hardness and solvent resistance, and does not cause display defects. Development is desired.

JP 2004-4669 A JP 2004-264623 A

  The present invention has been made on the basis of the circumstances as described above, and the object thereof is to have a good sensitivity and a feeling of having excellent flatness (residual film ratio) in addition to surface hardness and solvent resistance. An object is to provide a radiation resin composition, an interlayer insulating film for a display element obtained from the composition that does not cause display defects, and a method for forming the interlayer insulating film.

（式（１）中、Ｒ^１及びＲ^２は、それぞれ独立して水素原子、アルキル基、シクロアルキル基又はアリール基である。但し、上記アルキル基、シクロアルキル基及びアリール基が有する水素原子の一部又は全部は、置換されていてもよい。また、Ｒ^１及びＲ^２が共に水素原子である場合はない。Ｒ^３は、単結合、メチレン基、アルキレン基、アリーレン基、下記式（４）で表される基、又はこれらの基を組み合わせてなる２価の有機基である。但し、これらの基が有する水素原子の一部又は全部は、置換されていてもよい。Ｒ^４は、エポキシ基、グリシジル基、グリシジルオキシ基、不飽和二重結合若しくはエポキシ基を有する脂環式基、ビニル基、ビニルエーテル基又は（メタ）アクリロイル基である。但し、上記エポキシ基が有する水素原子の一部又は全部は、置換されていてもよい。ｎは、１〜３の整数である。但し、Ｒ^４が複数の場合、複数のＲ^４は同一であっても異なっていてもよい。）

（式（４）中、ａ、ｃは、それぞれ独立して１〜６の整数である。ｂは、１〜２の整数である。） The invention made to solve the above problems is
[A] a polymer containing a structural unit (I) having a group represented by the following formula (1) (hereinafter also referred to as “[A] polymer”), and [B] a radiation-sensitive acid generator It is a radiation sensitive resin composition.

(In formula (1), R ¹ and R ² are each independently a hydrogen atom, an alkyl group, a cycloalkyl group or an aryl group, provided that the hydrogen atom of the alkyl group, cycloalkyl group and aryl group is Some or all of them may be substituted, and R ¹ and R ² are not both hydrogen atoms, and R ³ is a single bond, a methylene group, an alkylene group, an arylene group, or a group represented by the following formula (4 ) is a divalent organic group comprising a combination of a group represented by or these groups. However, some or all of the hydrogen atoms with these groups may .R ⁴ be substituted, An epoxy group, a glycidyl group, a glycidyloxy group, an alicyclic group having an unsaturated double bond or an epoxy group, a vinyl group, a vinyl ether group, or a (meth) acryloyl group, provided that the epoxy group has Some or all of the atom, optionally substituted .n is an integer of 1 to 3. However, if R ⁴ is plural, even if a plurality of R ⁴ is optionally substituted by one or more identical Good.)

(In Formula (4), a and c are each independently an integer of 1 to 6. b is an integer of 1 to 2.)

  The structural unit (I) has a protective group having a reactive group, and the reactive group of the protective group dissociated by exposure reacts with the functional group of the polymer component in the resist film, thereby It becomes difficult to be discharged. As a result, the interlayer insulation film for display elements formed from the said composition containing the [A] polymer containing structural unit (I) can implement | achieve the outstanding residual film rate. In addition, the composition contains [B] a radiation-sensitive acid generator and has good sensitivity, and the interlayer insulating film for display elements formed from the composition has excellent surface hardness and resistance. It has solvent properties and can exhibit a higher voltage holding ratio (not causing display failure).

  [A] The polymer further includes a structural unit (II) having an epoxy group in a polymer molecule containing the structural unit (I) or in another polymer molecule not containing the structural unit (I). Is preferred. By further including the structural unit (II), the interlayer insulating film for a display element formed from the composition can have more excellent surface hardness, solvent resistance, and voltage holding ratio.

  The composition preferably further contains a [C] sensitizer. When the composition further contains a [C] sensitizer, the sensitivity of the composition can be further improved.

  The composition is suitable as a material for forming an interlayer insulating film for a display element. Further, the present invention suitably includes an interlayer insulating film for a display element formed from the composition.

The method for forming an interlayer insulating film for a display element according to the present invention includes:
(1) A step of applying the composition on a substrate to form a coating film,
(2) A step of irradiating at least a part of the coating film with radiation,
(3) a step of developing the coating film irradiated with the radiation; and (4) a step of heating the developed coating film.

  According to the formation method, an interlayer insulating film for a display element that has excellent flatness (remaining film ratio) and does not cause display defects can be formed. In addition, by forming a pattern by exposure, development, and heating using radiation sensitivity, an interlayer insulating film for a display element having a fine and elaborate pattern can be easily formed. Therefore, the formed interlayer insulation film for display elements can be used suitably for display elements, such as a liquid crystal display element and an organic EL display element.

  The “radiation” of the “radiation-sensitive resin composition” in the present specification is a concept including visible light, ultraviolet light, far ultraviolet light, X-rays, charged particle beams and the like.

  As described above, the radiation-sensitive resin composition of the present invention has good sensitivity, has excellent flatness (residual film ratio) in addition to surface hardness and solvent resistance, and has poor display. It is possible to form an interlayer insulating film for a display element that does not cause the problem. Therefore, the composition is suitable as a material for forming an interlayer insulating film for a display element such as a liquid crystal display element or an organic EL display element.

<Radiation sensitive resin composition>
The radiation sensitive resin composition of the present invention contains [A] a polymer and [B] a radiation sensitive acid generator. Moreover, the said composition may contain a [C] sensitizer as a suitable component. Furthermore, other optional components may be contained as long as the effects of the present invention are not impaired. Hereinafter, each component will be described in detail.

<[A] polymer>
[A] The polymer is a polymer containing the structural unit (I) having a group represented by the above formula (1). The structural unit (I) has a protective group having a reactive group, and the reactive group of the protective group dissociated by exposure reacts with the functional group of the polymer component in the resist film, thereby It becomes difficult to be discharged. As a result, the interlayer insulation film for display elements formed from the said composition containing the [A] polymer containing structural unit (I) can implement | achieve the outstanding residual film rate. [A] The polymer further comprises a structural unit (II) having an epoxy group in a polymer molecule containing the structural unit (I) or in another polymer molecule not containing the structural unit (I). It is preferable to include. Furthermore, the [A] polymer may contain the structural unit (III) containing an acetal structure and other structural units as long as the effects of the present invention are not impaired. In addition, the [A] polymer may contain 2 or more types of each structural unit. Hereinafter, each structural unit will be described in detail.

[Structural unit (I)]
The structural unit (I) has a group represented by the above formula (1). In said formula (1), R < ¹ > and R < ² > are respectively independently a hydrogen atom, an alkyl group, a cycloalkyl group, or an aryl group. However, one part or all part of the hydrogen atom which the said alkyl group, a cycloalkyl group, and an aryl group have may be substituted. Further, there is no case where R ¹ and R ² are both hydrogen atoms. R ³ is a single bond, a methylene group, an alkylene group, an arylene group, a group represented by the above formula (4), or a divalent organic group formed by combining these groups. However, some or all of the hydrogen atoms contained in these groups may be substituted. In said formula (4), a and c are the integers of 1-6 each independently. b is an integer of 1-2. R ⁴ is an epoxy group, a glycidyl group, a glycidyloxy group, an alicyclic group having an unsaturated double bond or an epoxy group, a vinyl group, a vinyl ether group, or a (meth) acryloyl group. However, one part or all part of the hydrogen atom which the said epoxy group has may be substituted. n is an integer of 1 to 3. However, when R ⁴ is plural, R ⁴ may be different and the same.

Examples of the alkyl group represented by R ¹ and R ² include linear and branched alkyl groups having 1 to 30 carbon atoms. Examples of the linear and branched alkyl group having 1 to 30 carbon atoms include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group, an n-hexyl group, and an n-octyl group. , N-dodecyl group, n-tetradecyl group, n-octadecyl group and other linear alkyl groups, i-propyl group, i-butyl group, t-butyl group, neopentyl group, 2-hexyl group, 3-hexyl group And a branched alkyl group such as.

Examples of the cycloalkyl group represented by R ¹ and R ² include a cycloalkyl group having 3 to 20 carbon atoms. Moreover, this C3-C20 cycloalkyl group may be polycyclic. Examples of the cycloalkyl group having 3 to 20 carbon atoms include cyclopropyl group, cyclopentyl group, cyclohexyl group, cycloheptyl, cyclooctyl, bornyl group, norbornyl group, adamantyl group and the like.

Examples of the aryl group represented by R ¹ and R ² include an aryl group having 6 to 14 carbon atoms. The aryl group having 6 to 14 carbon atoms may be a single ring, a structure in which single rings are connected, or a condensed ring. Examples of the aryl group having 6 to 14 carbon atoms include a phenyl group and a naphthyl group.

Examples of the optionally substituted alkyl group, cycloalkyl group and aryl group represented by R ¹ and R ² include a halogen atom, a hydroxyl group, a nitro group, a cyano group, a carboxyl group, a carbonyl group, a cyclo group. An alkyl group (eg, cyclopropyl group, cyclopentyl group, cyclohexyl group, cycloheptyl, cyclooctyl, bornyl group, norbornyl group, adamantyl group, etc.), aryl group (eg, phenyl group, naphthyl group, etc.), alkoxy group (eg, methoxy group) , An ethoxy group, a propoxy group, an n-butoxy group, a pentyloxy group, a hexyloxy group, a heptyloxy group, an octyloxy group and the like, and an acyl group (for example, an acetyl group and a propionyl group). , Butyryl group, i-butyryl group and the like having 2 to 20 carbon atoms A siloxy group), an acyloxy group (for example, an acetoxy group, an ethylyloxy group, a butyryloxy group, a t-butyryloxy group, a t-amylyloxy group, etc., an acyloxy group having 2 to 10 carbon atoms), an alkoxycarbonyl group (for example, a methoxycarbonyl group) C2-C20 alkoxycarbonyl groups such as ethoxycarbonyl group and propoxycarbonyl group), haloalkyl groups (for example, methyl group, ethyl group, n-propyl group, n-butyl group, n-pentyl group, n-hexyl group) , N-octyl group, n-dodecyl group, n-tetradecyl group, n-octadecyl group and the like linear alkyl group, i-propyl group, i-butyl group, t-butyl group, neopentyl group, 2-hexyl group Alkyl groups such as branched alkyl groups such as 3-hexyl groups; perfluoromethyl groups, perfluoro A group in which some or all of the hydrogen atoms of a cycloalkyl group such as an ethyl group, a perfluoropropyl group, a fluorocyclopropyl group, and a fluorocyclobutyl group are substituted with a halogen atom).

Examples of the alkylene group, arylene group, or divalent organic group formed by combining these groups represented by R ³ include one hydrogen atom from the alkyl group and aryl group exemplified for R ¹ and R ² above. Excluded groups and divalent organic groups formed by combining these groups are applicable. As the substituent for these groups, for example, the groups exemplified as substituents for the optionally substituted alkyl group, cycloalkyl group and aryl group represented by R ¹ and R ² can be applied.

Examples of the alicyclic group of the alicyclic group having an unsaturated double bond or an epoxy group represented by R ⁴ include a cycloalkyl group having 3 to 20 carbon atoms. Moreover, this C3-C20 cycloalkyl group may be polycyclic. Examples of the cycloalkyl group having 3 to 20 carbon atoms include cyclopropyl group, cyclopentyl group, cyclohexyl group, cycloheptyl, cyclooctyl, bornyl group, norbornyl group, adamantyl group and the like. The epoxy group is a concept including an oxiranyl group (1,2-epoxy structure) and an oxetanyl group (1,3-epoxy structure). Examples of the substituent of the optionally substituted epoxy group represented by R ⁴ include linear and branched alkyl groups having 1 to 10 carbon atoms. Examples of the linear and branched alkyl group having 1 to 10 carbon atoms include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group, an n-hexyl group, and an n-octyl group. And a linear alkyl group such as i-propyl group, i-butyl group, t-butyl group, neopentyl group, 2-hexyl group and 3-hexyl group.

  Examples of the group represented by the above formula (1) include groups represented by the following formulas (1-1) to (1-7).

  [A] The content of the structural unit (I) in the polymer is not particularly limited as long as the desired effect of the invention of the present application is achieved, and [A] is a single amount with respect to all the structural units contained in the polymer. The body charge ratio is preferably 5% by mass to 80% by mass, more preferably 10% by mass to 70% by mass, and particularly preferably 15% by mass to 65% by mass.

[Structural unit (II)]
[A] The polymer may further include a structural unit (II) having an epoxy group in a polymer molecule containing the structural unit (I) or in another polymer molecule not containing the structural unit (I). preferable. By further including the structural unit (II), the interlayer insulating film for a display element formed from the composition can have more excellent surface hardness, solvent resistance, and voltage holding ratio. The structural unit (II) is not particularly limited as long as it is a structural unit derived from an epoxy group-containing monomer.

As an embodiment of the [A] polymer containing the structural unit (I) and the structural unit (II), for example, (i) including both the structural unit (I) and the structural unit (II) in the same polymer molecule [A] when one polymer molecule is present in the polymer;
(Ii) In the case where the structural unit (I) is contained in one polymer molecule and the structural unit (II) is contained in a different polymer molecule, and [A] two polymer molecules are present in the polymer. ;
(Iii) A polymer molecule containing both the structural unit (I) and the structural unit (II) in one polymer molecule and a structural unit (I) in a polymer molecule different from the structural unit (I). In the case of containing the structural unit (II), and [A] three kinds of polymer molecules are present in the polymer;
(Iv) In addition to the polymer molecules of (i) to (iii) above, there may be mentioned a case where [A] the polymer further contains one or more polymer molecules.

Examples of the epoxy group-containing monomer that gives an epoxy group-containing structural unit include glycidyl (meth) acrylate, 3,4-epoxybutyl (meth) acrylate, 3-methyl-3,4-epoxybutyl acrylate, and methacrylic acid. 3-ethyl-3,4-epoxybutyl acid, 5,6-epoxyhexyl (meth) acrylate, 5-methyl-5,6-epoxyhexyl methacrylate, 5-ethyl-5,6-epoxyhexyl methacrylate, (Meth) acrylic acid 6,7-epoxyheptyl, 3,4-epoxycyclohexyl methacrylate, 3,4-epoxycyclohexylmethyl methacrylate, 3,4-epoxycyclohexylethyl (meth) acrylate, methacrylic acid 3,4-epoxycyclohexylpropyl, 3,4-epoxycyclohexyl methacrylate Chill, 3,4-epoxycyclohexylhexyl (meth) acrylate, 3,4-epoxycyclohexylmethyl acrylate, 3,4-epoxycyclohexylethyl acrylate, 3,4-epoxycyclohexylpropyl acrylate Oxiranyl group-containing (meth) acrylic compounds such as 3,4-epoxycyclohexylbutyl acrylate, 3,4-epoxycyclohexylhexyl acrylate;
o-vinyl benzyl glycidyl ether, m-vinyl benzyl glycidyl ether, p-vinyl benzyl glycidyl ether, α-methyl-o-vinyl benzyl glycidyl ether, α-methyl-m-vinyl benzyl glycidyl ether, α-methyl-p-vinyl Vinyl benzyl glycidyl ethers such as benzyl glycidyl ether;
vinyl phenyl glycidyl ethers such as o-vinyl phenyl glycidyl ether, m-vinyl phenyl glycidyl ether, p-vinyl phenyl glycidyl ether;
3- (acryloyloxymethyl) oxetane, 3- (acryloyloxymethyl) -3-methyloxetane, 3- (acryloyloxymethyl) -3-ethyloxetane, 3- (acryloyloxymethyl) -3-phenyloxetane, 3- (2-acryloyloxyethyl) oxetane, 3- (2-acryloyloxyethyl) -3-ethyloxetane, 3- (2-acryloyloxyethyl) -3-ethyloxetane, 3- (2-acryloyloxyethyl) -3 -Phenyloxetane, 3- (methacryloyloxymethyl) oxetane, 3- (methacryloyloxymethyl) -3-methyloxetane, 3- (methacryloyloxymethyl) -3-ethyloxetane, 3- (methacryloyloxymethyl) -3-phenyl Oxetane, -(2-methacryloyloxyethyl) oxetane, 3- (2-methacryloyloxyethyl) -3-ethyloxetane, 3- (2-methacryloyloxyethyl) -3-ethyloxetane, 3- (2-methacryloyloxyethyl)- 3-phenyloxetane, 2- (acryloyloxymethyl) oxetane, 2- (acryloyloxymethyl) -2-methyloxetane, 2- (acryloyloxymethyl) -2-ethyloxetane, 2- (acryloyloxymethyl) -2- Phenyloxetane, 2- (2-acryloyloxyethyl) oxetane, 2- (2-acryloyloxyethyl) -2-ethyloxetane, 2- (2-acryloyloxyethyl) -2-ethyloxetane, 2- (2-acryloyl) Oxyethyl) -2-fe Luoxetane, 2- (methacryloyloxymethyl) oxetane, 2- (methacryloyloxymethyl) -2-methyloxetane, 2- (methacryloyloxymethyl) -2-ethyloxetane, 2- (methacryloyloxymethyl) -2-phenyloxetane, 2- (2-methacryloyloxyethyl) oxetane, 2- (2-methacryloyloxyethyl) -2-ethyloxetane, 2- (2-methacryloyloxyethyl) -2-ethyloxetane, 2- (2-methacryloyloxyethyl) Examples include oxetanyl group-containing (meth) acrylic compounds such as 2-phenyloxetane.

  Among the above epoxy group-containing monomers, glycidyl methacrylate, 2-methylglycidyl methacrylate, 3,4-epoxycyclohexyl methacrylate, 3,4-epoxycyclohexylmethyl methacrylate, 3- (methacryloyloxymethyl) -3- Methyl oxetane and 3- (methacryloyloxymethyl) -3-ethyloxetane are preferable from the viewpoint of copolymerization reactivity with other radical polymerizable monomers and developability of the composition.

  [A] The content of the structural unit (II) in the polymer is not particularly limited as long as the desired effect of the invention of the present application is exhibited, and [A] a single amount with respect to all the structural units contained in the polymer. The body charge ratio is preferably 5% by mass to 60% by mass, more preferably 7% by mass to 55% by mass, and particularly preferably 10% by mass to 50% by mass.

[Structural unit (III)]
The structural unit (III) has an acid-dissociable group and is a structural unit having no reactive group in the structural unit (I), that is, a group corresponding to R ⁴ . The acid dissociable group in the structural unit (III) has an acetal structure or a ketal structure that is relatively stable with respect to an alkali, and these are dissociated by the action of an acid.

  Examples of the monomer that gives the structural unit (III) include 1-ethoxyethyl methacrylate, 1-methoxyethyl methacrylate, 1-n-butoxyethyl methacrylate, 1-isobutoxyethyl methacrylate, 1-t methacrylate. -Butoxyethyl, 1- (2-chloroethoxy) ethyl methacrylate, 1- (2-ethylhexyloxy) ethyl methacrylate, 1-n-propoxyethyl methacrylate, 1-cyclohexyloxyethyl methacrylate, 1- (methacrylic acid 1- ( 2-cyclohexylethoxy) ethyl, 1-benzyloxyethyl methacrylate, 2-tetrahydropyranyl methacrylate, 1-ethoxyethyl acrylate, 1-methoxyethyl acrylate, 1-n-butoxyethyl acrylate, 1-acrylate Isobutoxyethyl, acrylic 1-t-butoxyethyl, 1- (2-chloroethoxy) ethyl acrylate, 1- (2-ethylhexyloxy) ethyl acrylate, 1-n-propoxyethyl acrylate, 1-cyclohexyloxyethyl acrylate, acrylic acid 1- (2-cyclohexylethoxy) ethyl, 1-benzyloxyethyl acrylate, 2-tetrahydropyranyl acrylate, 2,3-di (1- (trimethylsilanyloxy) ethoxy) carbonyl) -5-norbornene, 2 , 3-Di (1- (trimethylgermyloxy) ethoxy) carbonyl) -5-norbornene, 2,3-di (1-methoxyethoxycarbonyl) -5-norbornene, 2,3-di (1- (cyclohexyloxy) ) Ethoxycarbonyl) -5-norbornene, 2,3-di (1- (benzylo) Ii) ethoxycarbonyl) -5-norbornene, p or m-1-ethoxyethoxystyrene, p or m-1-methoxyethoxystyrene, p or m-1-n-butoxyethoxystyrene, p or m-1-isobutoxy Ethoxystyrene, p or m-1- (1,1-dimethylethoxy) ethoxystyrene, p or m-1- (2-chloroethoxy) ethoxystyrene, p or m-1- (2-ethylhexyloxy) ethoxystyrene, p or m-1-n-propoxyethoxystyrene, p or m-1-cyclohexyloxyethoxystyrene, p or m-1- (2-cyclohexylethoxy) ethoxystyrene, p or m-1-benzyloxyethoxystyrene, etc. Can be mentioned.

  Among these, monomers giving structural unit (III) include 1-ethoxyethyl methacrylate, 1-n-butoxyethyl methacrylate, 2-tetrahydropyranyl methacrylate, 1-benzyloxyethyl methacrylate, methacrylic acid. 1-cyclohexyloxyethyl is preferred.

[Other structural units]
[A] The polymer may contain other structural units other than the structural unit (I), the structural unit (II) and the structural unit (III) as long as the effects of the present invention are not impaired. Examples of the monomer that gives other structural units include a monomer having a carboxyl group or a derivative thereof, a monomer having a hydroxyl group, and other monomers.

  Examples of the monomer having a carboxyl group or a derivative thereof include acrylic acid, methacrylic acid, crotonic acid, 2-acryloyloxyethyl succinic acid, 2-methacryloyloxyethyl succinic acid, 2-acryloyloxyethyl hexahydrophthalic acid, Examples thereof include monocarboxylic acids such as 2-methacryloyloxyethyl hexahydrophthalic acid; dicarboxylic acids such as maleic acid, fumaric acid, citraconic acid, mesaconic acid, and itaconic acid; and acid anhydrides of the above dicarboxylic acids.

  Examples of the monomer having a hydroxyl group include hydroxyalkyl acrylates such as 2-hydroxyethyl acrylate, 3-hydroxypropyl acrylate, 4-hydroxybutyl acrylate, 4-hydroxymethylcyclohexylmethyl acrylate; methacrylic acid 2 -Hydroxyethyl, 3-hydroxypropyl methacrylate, 4-hydroxybutyl methacrylate, 5-hydroxypentyl methacrylate, 6-hydroxyhexyl methacrylate, 4-hydroxymethyl methacrylate-hydroxyalkyl methacrylate and the like. It is done. Of these monomers having a hydroxyl group, 2-hydroxyethyl acrylate, 3-hydroxypropyl acrylate, 4-hydroxybutyl acrylate, and methacrylic acid 2 are used from the viewpoint of heat resistance of the obtained interlayer insulating film for display elements. -Hydroxyethyl, 4-hydroxybutyl methacrylate, 4-hydroxymethyl-cyclohexylmethyl acrylate, 4-hydroxymethyl-cyclohexylmethyl methacrylate are preferred.

Examples of other monomers include alkyl acrylates such as methyl acrylate and i-propyl acrylate;
Alkyl methacrylates such as methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, sec-butyl methacrylate, t-butyl methacrylate;
Cyclohexyl acrylate, 2-methylcyclohexyl acrylate, tricyclo [5.2.1.0 ^2,6 ] decan-8-yl acrylate, 2- (tricyclo [5.2.1.0 ^2,6 ] acrylate Decyl-8-yloxy) ethyl, cycloaliphatic alkyl acrylates such as isobornyl acrylate;
Cyclohexyl methacrylate, 2-methylcyclohexyl methacrylate, tricyclo [5.2.1.0 ^2,6 ] decane-8-yl methacrylate, 2- (tricyclo [5.2.1.0 ^2,6 ] methacrylate) Decane-8-yloxy) ethyl, cycloaliphatic alkyl methacrylates such as isobornyl methacrylate;
Aryl esters of acrylic acid such as phenyl acrylate and benzyl acrylate or aralkyl of acrylic acid;
Aryl esters of methacrylic acid such as phenyl methacrylate and benzyl methacrylate or aralkyl of methacrylic acid;
Dialkyl dicarboxylates such as diethyl maleate, diethyl fumarate, diethyl itaconate;
Unsaturated hetero 5-membered methacrylic acid ester or unsaturated hetero 6-membered methacrylic acid containing 1 atom of oxygen such as tetrahydrofurfuryl methacrylate, tetrahydrofuryl methacrylate, tetrahydropyran-2-methyl methacrylate;
4-methacryloyloxymethyl-2-methyl-2-ethyl-1,3-dioxolane, 4-methacryloyloxymethyl-2-methyl-2-isobutyl-1,3-dioxolane, 4-methacryloyloxymethyl-2-cyclohexyl- 2 oxygen atoms such as 1,3-dioxolane, 4-methacryloyloxymethyl-2-methyl-2-ethyl-1,3-dioxolane, 4-methacryloyloxymethyl-2-methyl-2-isobutyl-1,3-dioxolane An unsaturated heterocyclic 5-membered methacrylic acid containing:
4-acryloyloxymethyl-2,2-dimethyl-1,3-dioxolane, 4-acryloyloxymethyl-2-methyl-2-ethyl-1,3-dioxolane, 4-acryloyloxymethyl-2, 2-diethyl- 1,3-dioxolane, 4-acryloyloxymethyl-2-methyl-2-isobutyl-1,3-dioxolane, 4-acryloyloxymethyl-2-cyclopentyl-1,3-dioxolane, 4-acryloyloxymethyl-2- Cyclohexyl-1,3-dioxolane, 4-acryloyloxyethyl-2-methyl-2-ethyl-1,3-dioxolane, 4-acryloyloxypropyl-2-methyl-2-ethyl-1,3-dioxolane, 4- Acryloyloxybutyl-2-methyl-2-ethyl-1,3-dioxola Unsaturated five-membered heterocyclic acrylic acid containing oxygen 2 atoms and the like;
Vinyl aromatic compounds such as styrene, α-methylstyrene, m-methylstyrene, p-methylstyrene, p-methoxystyrene, 4-isopropenylphenol;
N-phenylmaleimide, N-cyclohexylmaleimide, N-benzylmaleimide, N-succinimidyl-3-maleimidobenzoate, N-succinimidyl-4-maleimidobutyrate, N-succinimidyl-6-maleimidocaproate, N-succinimidyl-3 -N-substituted maleimides such as maleimide propionate, N- (9-acridinyl) maleimide;
Conjugated diene compounds such as 1,3-butadiene, isoprene and 2,3-dimethyl-1,3-butadiene;
And unsaturated compounds such as acrylonitrile, methacrylonitrile, acrylamide, methacrylamide, vinyl chloride, vinylidene chloride and vinyl acetate.

Among these other monomers, styrene, 4-isopropenylphenol, tricyclo [5.2.1.0 ^2,6 ] decan-8-yl methacrylate, tetrahydrofurfuryl methacrylate, 1,3-butadiene 4-acryloyloxymethyl-2-methyl-2-ethyl-1,3-dioxolane, N-cyclohexylmaleimide, N-phenylmaleimide, benzyl methacrylate is a monomer having the above carboxyl group or a derivative thereof, a hydroxyl group From the viewpoints of copolymerization reactivity with a monomer having a photopolymerization property and developability of the composition.

[A] Polystyrene conversion weight average molecular weight (Mw) by gel permeation chromatography (GPC) of the polymer is preferably 2.0 × 10 ^{3 to} 1.0 × 10 ⁵ , more preferably 5.0 × 10. ^{3 to} 5.0 × 10 ⁴ . [A] By making Mw of a polymer into the said specific range, the sensitivity and alkali developability of the said composition can be improved.

[A] The number average molecular weight (Mn) in terms of polystyrene by GPC of the polymer is preferably 2.0 × 10 ^{3 to} 1.0 × 10 ⁵ , more preferably 5.0 × 10 ^{3 to} 5.0 × 10. ⁴ . [A] By making Mn of a polymer into the said specific range, the curing reactivity at the time of hardening of the coating film of the said composition can be improved.

  [A] The molecular weight distribution (Mw / Mn) of the polymer is preferably 3.0 or less, more preferably 2.6 or less. [A] By setting Mw / Mn of the polymer to 3.0 or less, the developability of the obtained interlayer insulating film for display elements can be enhanced.

Mw and Mn were measured by GPC under the following conditions.
Apparatus: GPC-101 (made by Showa Denko)
Column: GPC-KF-801, GPC-KF-802, GPC-KF-803 and GPC-KF-804 are combined Mobile phase: Tetrahydrofuran Column temperature: 40 ° C
Flow rate: 1.0 mL / min Sample concentration: 1.0% by mass
Sample injection volume: 100 μL
Detector: Differential refractometer Standard material: Monodisperse polystyrene

<[A] Polymer Synthesis Method>
[A] The polymer can be synthesized by radical copolymerization of monomers giving the above structural units. For example, when synthesizing a polymer [A] containing both the structural unit (I) and the structural unit (II) in the same polymer molecule, the monomer that gives the structural unit (I) and the structural unit (II) What is necessary is just to copolymerize using the mixture containing the monomer which gives. On the other hand, when the [A] polymer having the structural unit (I) in one polymer molecule and the structural unit (II) in a different polymer molecule is synthesized, the structural unit (I) is given. A polymer solution containing a monomer is radically polymerized to obtain a polymer molecule having the structural unit (I), and a polymer solution containing a monomer that gives the structural unit (II) is separately radically polymerized to form a structure. What is necessary is just to obtain the polymer molecule | numerator which has a unit (II), and finally mix both to make a [A] polymer.

  [A] Examples of the solvent used in the polymerization reaction of the polymer include the solvents exemplified in the section of preparation of the composition described later.

  As the polymerization initiator used in the polymerization reaction, those generally known as radical polymerization initiators can be used. For example, 2,2′-azobisisobutyronitrile, 2,2′-azobis- ( 2,4-Dimethylvaleronitrile), 2,2′-azobis- (4-methoxy-2,4-dimethylvaleronitrile), azo compounds such as 2,2′-azobis (methyl 2-methylpropionate); benzoyl And organic peroxides such as peroxide, lauroyl peroxide, t-butylperoxypivalate, 1,1′-bis- (t-butylperoxy) cyclohexane; and hydrogen peroxide.

  [A] In the polymerization reaction of the polymer, a molecular weight modifier may be used to adjust the molecular weight. Examples of the molecular weight modifier include halogenated hydrocarbons such as chloroform and carbon tetrabromide; mercaptans such as n-hexyl mercaptan, n-octyl mercaptan, n-dodecyl mercaptan, t-dodecyl mercaptan, and thioglycolic acid; Xanthogens such as xanthogen sulfide and diisopropylxanthogen disulfide; terpinolene, α-methylstyrene dimer and the like.

<[B] Radiation sensitive acid generator>
[B] The radiation-sensitive acid generator is a compound that generates an acid upon irradiation with radiation. As the radiation, for example, visible light, ultraviolet light, far ultraviolet light, electron beam, X-ray or the like can be used. When the composition contains the [B] radiation sensitive acid generator, the composition can exhibit positive radiation sensitive characteristics.

  [B] Examples of the radiation-sensitive acid generator include oxime sulfonate compounds, onium salts, sulfonimide compounds, halogen-containing compounds, diazomethane compounds, sulfone compounds, sulfonic acid ester compounds, and carboxylic acid ester compounds. In addition, each of these [B] radiation sensitive acid generators can be used individually or in combination of 2 or more types.

[Oxime sulfonate compound]
Examples of the oxime sulfonate compound include a compound containing an oxime sulfonate group represented by the following formula (2).

In the above formula (2), R ^B1 is a linear or branched alkyl group, cycloalkyl group, or aryl group. However, in these groups, some or all of the hydrogen atoms may be substituted.

The linear or branched alkyl group represented by R ^B1 is preferably a linear or branched alkyl group having 1 to 10 carbon atoms. The linear or branched alkyl group having 1 to 10 carbon atoms may be substituted. Examples of the substituent include an alkoxy group having 1 to 10 carbon atoms and 7,7-dimethyl-2-oxonorbornyl. And an alicyclic group containing a bridged alicyclic group such as a group. A preferred alicyclic group is a bicycloalkyl group. The aryl group represented by R ^B1 is preferably an aryl group having 6 to 11 carbon atoms, and more preferably a phenyl group or a naphthyl group. The aryl group may be substituted, and examples of the substituent include an alkyl group having 1 to 5 carbon atoms, an alkoxy group, and a halogen atom.

  Examples of the compound containing an oxime sulfonate group represented by the above formula (2) include an oxime sulfonate compound represented by the following formula (3).

In the above formula (3), R ^B1 has the same ^{meaning as} in the above formula (2). X is an alkyl group, an alkoxy group, or a halogen atom. m is an integer of 0-3. However, when there are a plurality of Xs, the plurality of Xs may be the same or different.

  The alkyl group that can be represented by X is preferably a linear or branched alkyl group having 1 to 4 carbon atoms. The alkoxy group represented by X is preferably a linear or branched alkoxy group having 1 to 4 carbon atoms. The halogen atom represented by X is preferably a chlorine atom or a fluorine atom. As m, 0 or 1 is preferable. In the above formula (3), a compound in which m is 1, X is a methyl group, and the substitution position of X is ortho is preferable.

  Examples of the oxime sulfonate compound represented by the above (3) include compounds represented by the following formulas (3-1) to (3-5).

  Compound (3-1) (5-propylsulfonyloxyimino-5H-thiophen-2-ylidene)-(2-methylphenyl) acetonitrile, Compound (3-2) (5-octylsulfonyloxyimino-5H-thiophene- 2-Ilidene)-(2-methylphenyl) acetonitrile, Compound (3-3) (camphorsulfonyloxyimino-5H-thiophen-2-ylidene)-(2-methylphenyl) acetonitrile, Compound (3-4) (5 -P-toluenesulfonyloxyimino-5H-thiophen-2-ylidene)-(2-methylphenyl) acetonitrile and compound (3-5) (5-octylsulfonyloxyimino)-(4-methoxyphenyl) acetonitrile are commercially available. Available as a product.

[Onium salt]
Examples of the onium salt include diphenyliodonium salt, triphenylsulfonium salt, sulfonium salt, benzothiazonium salt, and tetrahydrothiophenium salt.

  Examples of the diphenyliodonium salt include diphenyliodonium tetrafluoroborate, diphenyliodonium hexafluorophosphonate, diphenyliodonium hexafluoroarsenate, diphenyliodonium trifluoromethanesulfonate, diphenyliodonium trifluoroacetate, diphenyliodonium-p-toluenesulfonate, diphenyliodonium. Butyltris (2,6-difluorophenyl) borate, 4-methoxyphenylphenyliodonium tetrafluoroborate, bis (4-t-butylphenyl) iodonium tetrafluoroborate, bis (4-t-butylphenyl) iodonium hexafluoroarsenate Bis (4-t-butylphenyl) iodonium trifluorome Sulphonate, bis (4-t-butylphenyl) iodonium trifluoroacetate, bis (4-t-butylphenyl) iodonium-p-toluenesulfonate, bis (4-t-butylphenyl) iodonium camphorsulfonic acid, etc. .

  Examples of the triphenylsulfonium salt include triphenylsulfonium trifluoromethanesulfonate, triphenylsulfonium camphorsulfonic acid, triphenylsulfonium tetrafluoroborate, triphenylsulfonium trifluoroacetate, triphenylsulfonium-p-toluenesulfonate, triphenylsulfonium. And butyl tris (2,6-difluorophenyl) borate.

  Examples of the sulfonium salt include alkylsulfonium salts, benzylsulfonium salts, dibenzylsulfonium salts, substituted benzylsulfonium salts and the like.

  Examples of the alkylsulfonium salt include 4-acetoxyphenyldimethylsulfonium hexafluoroantimonate, 4-acetoxyphenyldimethylsulfonium hexafluoroarsenate, dimethyl-4- (benzyloxycarbonyloxy) phenylsulfonium hexafluoroantimonate, dimethyl-4- (Benzoyloxy) phenylsulfonium hexafluoroantimonate, dimethyl-4- (benzoyloxy) phenylsulfonium hexafluoroarsenate, dimethyl-3-chloro-4-acetoxyphenylsulfonium hexafluoroantimonate and the like can be mentioned.

  Examples of the benzylsulfonium salt include benzyl-4-hydroxyphenylmethylsulfonium hexafluoroantimonate, benzyl-4-hydroxyphenylmethylsulfonium hexafluorophosphate, 4-acetoxyphenylbenzylmethylsulfonium hexafluoroantimonate, benzyl-4-methoxyphenyl. Methylsulfonium hexafluoroantimonate, benzyl-2-methyl-4-hydroxyphenylmethylsulfonium hexafluoroantimonate, benzyl-3-chloro-4-hydroxyphenylmethylsulfonium hexafluoroarsenate, 4-methoxybenzyl-4-hydroxyphenyl Examples include methylsulfonium hexafluorophosphate.

  Examples of the dibenzylsulfonium salt include dibenzyl-4-hydroxyphenylsulfonium hexafluoroantimonate, dibenzyl-4-hydroxyphenylsulfonium hexafluorophosphate, 4-acetoxyphenyl dibenzylsulfonium hexafluoroantimonate, and dibenzyl-4-methoxyphenylsulfonium. Hexafluoroantimonate, dibenzyl-3-chloro-4-hydroxyphenylsulfonium hexafluoroarsenate, dibenzyl-3-methyl-4-hydroxy-5-t-butylphenylsulfonium hexafluoroantimonate, benzyl-4-methoxybenzyl- Examples include 4-hydroxyphenylsulfonium hexafluorophosphate.

  Examples of substituted benzylsulfonium salts include p-chlorobenzyl-4-hydroxyphenylmethylsulfonium hexafluoroantimonate, p-nitrobenzyl-4-hydroxyphenylmethylsulfonium hexafluoroantimonate, and p-chlorobenzyl-4-hydroxyphenylmethyl. Sulfonium hexafluorophosphate, p-nitrobenzyl-3-methyl-4-hydroxyphenylmethylsulfonium hexafluoroantimonate, 3,5-dichlorobenzyl-4-hydroxyphenylmethylsulfonium hexafluoroantimonate, o-chlorobenzyl-3- Examples include chloro-4-hydroxyphenylmethylsulfonium hexafluoroantimonate.

  Examples of the benzothiazonium salt include 3-benzylbenzothiazonium hexafluoroantimonate, 3-benzylbenzothiazonium hexafluorophosphate, 3-benzylbenzothiazonium tetrafluoroborate, and 3- (p-methoxybenzyl). ) Benzothiazonium hexafluoroantimonate, 3-benzyl-2-methylthiobenzothiazonium hexafluoroantimonate, 3-benzyl-5-chlorobenzothiazonium hexafluoroantimonate, and the like.

  Examples of tetrahydrothiophenium salts include 4,7-di-n-butoxy-1-naphthyltetrahydrothiophenium trifluoromethanesulfonate and 1- (4-n-butoxynaphthalen-1-yl) tetrahydrothiophenium trifluoromethane. Sulfonate, 1- (4-n-butoxynaphthalen-1-yl) tetrahydrothiophenium nonafluoro-n-butanesulfonate, 1- (4-n-butoxynaphthalen-1-yl) tetrahydrothiophenium-1,1 , 2,2-Tetrafluoro-2- (norbornan-2-yl) ethanesulfonate, 1- (4-n-butoxynaphthalen-1-yl) tetrahydrothiophenium-2- (5-t-butoxycarbonyloxybicyclo) [2.2.1] Heptan-2-yl) -1,1, , 2-tetrafluoroethanesulfonate, 1- (4-n-butoxynaphthalen-1-yl) tetrahydrothiophenium-2- (6-t-butoxycarbonyloxybicyclo [2.2.1] heptan-2-yl ) -1,1,2,2-tetrafluoroethanesulfonate and the like.

[Sulfonimide compound]
Examples of the sulfonimide compound include N- (trifluoromethylsulfonyloxy) succinimide, N- (camphorsulfonyloxy) succinimide, N- (4-methylphenylsulfonyloxy) succinimide, N- (2-trifluoromethylphenylsulfonyloxy). ) Succinimide, N- (4-fluorophenylsulfonyloxy) succinimide, N- (trifluoromethylsulfonyloxy) phthalimide, N- (camphorsulfonyloxy) phthalimide, N- (2-trifluoromethylphenylsulfonyloxy) phthalimide, N -(2-fluorophenylsulfonyloxy) phthalimide, N- (trifluoromethylsulfonyloxy) diphenylmaleimide, N- (camphorsulfonyloxy) diphenyl monomer Imido, 4-methylphenylsulfonyloxy) diphenylmaleimide, N- (2-trifluoromethylphenylsulfonyloxy) diphenylmaleimide, N- (4-fluorophenylsulfonyloxy) diphenylmaleimide, N- (4-fluorophenylsulfonyloxy) Diphenylmaleimide, N- (phenylsulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboxylimide, N- (4-methylphenylsulfonyloxy) bicyclo [2.2.1] Hept-5-ene-2,3-dicarboxylimide, N- (trifluoromethanesulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboxylimide, N- (nonafluorobutane Sulfonyloxy) bicyclo [2.2.1] Pto-5-ene-2,3-dicarboxylimide, N- (camphorsulfonyloxy) bicyclo [2.2.1] hept-5-en-2,3-dicarboxylimide, N- (camphorsulfonyloxy) -7-oxabicyclo [2.2.1] hept-5-ene-2,3-dicarboxylimide, N- (trifluoromethylsulfonyloxy) -7-oxabicyclo [2.2.1] hept-5 -Ene-2,3-dicarboxylimide, N- (4-methylphenylsulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboxylimide, N- (4-methylphenyl) Sulfonyloxy) -7-oxabicyclo [2.2.1] hept-5-ene-2,3-dicarboxylimide, N- (2-trifluoromethylphenylsulfonyl) Ruoxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboxylimide, N- (2-trifluoromethylphenylsulfonyloxy) -7-oxabicyclo [2.2.1] hept- 5-ene-2,3-dicarboxylimide, N- (4-fluorophenylsulfonyloxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboxylimide, N- (4-fluoro Phenylsulfonyloxy) -7-oxabicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (trifluoromethylsulfonyloxy) bicyclo [2.2.1] heptane-5 , 6-oxy-2,3-dicarboxylimide, N- (camphorsulfonyloxy) bicyclo [2.2.1] heptane-5,6-oxy-2,3-di Ruboxylimide, N- (4-methylphenylsulfonyloxy) bicyclo [2.2.1] heptane-5,6-oxy-2,3-dicarboxylimide, N- (2-trifluoromethylphenylsulfonyloxy) bicyclo [2.2.1] Heptane-5,6-oxy-2,3-dicarboxylimide, N- (4-fluorophenylsulfonyloxy) bicyclo [2.2.1] heptane-5,6-oxy-2 , 3-dicarboxylimide, N- (trifluoromethylsulfonyloxy) naphthyl dicarboxylimide, N- (camphorsulfonyloxy) naphthyl dicarboxylimide, N- (4-methylphenylsulfonyloxy) naphthyl dicarboxylimide, N- (Phenylsulfonyloxy) naphthyl dicarboxylimide, N- 2-trifluoromethylphenylsulfonyloxy) naphthyl dicarboxylimide, N- (4-fluorophenylsulfonyloxy) naphthyl dicarboxylimide, N- (pentafluoroethylsulfonyloxy) naphthyl dicarboxylimide, N- (heptafluoropropylsulfonyl) Oxy) naphthyl dicarboxylimide, N- (nonafluorobutylsulfonyloxy) naphthyl dicarboxylimide, N- (ethylsulfonyloxy) naphthyl dicarboxylimide, N- (propylsulfonyloxy) naphthyl dicarboxylimide, N- (butylsulfonyl) Oxy) naphthyl dicarboxylimide, N- (pentylsulfonyloxy) naphthyl dicarboxylimide, N- (hexylsulfonyloxy) naphthyl dicarbo Xylimide, N- (heptylsulfonyloxy) naphthyl dicarboxylimide, N- (octylsulfonyloxy) naphthyl dicarboxylimide, N- (nonylsulfonyloxy) naphthyl dicarboxylimide, and the like.

[Halogen-containing compounds]
Examples of the halogen-containing compound include haloalkyl group-containing hydrocarbon compounds and haloalkyl group-containing heterocyclic compounds.

[Diazomethane compounds]
Examples of the diazomethane compound include bis (trifluoromethylsulfonyl) diazomethane, bis (cyclohexylsulfonyl) diazomethane, bis (phenylsulfonyl) diazomethane, bis (p-tolylsulfonyl) diazomethane, and bis (2,4-xylylsulfonyl) diazomethane. Bis (p-chlorophenylsulfonyl) diazomethane, methylsulfonyl-p-toluenesulfonyldiazomethane, cyclohexylsulfonyl (1,1-dimethylethylsulfonyl) diazomethane, bis (1,1-dimethylethylsulfonyl) diazomethane, phenylsulfonyl (benzoyl) diazomethane Etc.

[Sulfone compound]
Examples of the sulfone compounds include β-ketosulfone compounds, β-sulfonylsulfone compounds, diaryldisulfone compounds, and the like.

[Sulfonic acid ester compounds]
Examples of the sulfonate compound include alkyl sulfonate, haloalkyl sulfonate, aryl sulfonate, and imino sulfonate.

[Carboxylic ester compounds]
Examples of the carboxylic acid ester compound include carboxylic acid o-nitrobenzyl ester.

  [B] The radiation-sensitive acid generator is preferably an oxime sulfonate compound, an onium salt, or a sulfonate compound from the viewpoints of sensitivity and solubility. As the oxime sulfonate compound, a compound represented by the above formula (2) is preferable, a compound represented by the above formula (3) is more preferable, and is represented by the above formula (3-1), which is available as a commercial product. Are particularly preferred. As the onium salt, tetrahydrothiophenium salt and benzylsulfonium salt are preferable, and 4,7-di-n-butoxy-1-naphthyltetrahydrothiophenium trifluoromethanesulfonate and benzyl-4-hydroxyphenylmethylsulfonium hexafluorophosphate are preferable. More preferred. As the sulfonic acid ester compound, a haloalkylsulfonic acid ester is preferable, and N-hydroxynaphthalimide-trifluoromethanesulfonic acid ester is more preferable.

  As content of the [B] radiation sensitive acid generator in the said composition, Preferably it is 0.1 mass part-10 mass parts with respect to 100 mass parts of [A] polymers, More preferably, 1 mass part- 5 parts by mass. [B] By setting the content of the radiation-sensitive acid generator within the specific range, the sensitivity of the composition can be optimized, and an interlayer insulating film for a display element having a high surface hardness can be formed while maintaining transparency.

<[C] sensitizer>
It is preferable that the said composition further contains a [C] sensitizer as a suitable component. When the composition further contains a [C] sensitizer, the sensitivity of the composition can be further improved. [C] The sensitizer absorbs actinic rays or radiation and enters an electronically excited state. The electronically excited [C] sensitizer is brought into contact with the photoacid generator to cause electron transfer, energy transfer, heat generation, and the like, whereby the [B] radiation sensitive acid generator is chemically changed. To generate acid.

  [C] Examples of the sensitizer include compounds belonging to the following compounds and having an absorption wavelength in the region of 350 nm to 450 nm.

[C] Examples of the sensitizer include pyrene, perylene, triphenylene, anthracene, 9,10-dibutoxyanthracene, 9,10-diethoxyanthracene, 3,7-dimethoxyanthracene, 9,10-dipropyloxyanthracene and the like. Polynuclear aromatics of
Xanthenes such as fluorescein, eosin, erythrosine, rhodamine B, rose bengal;
Xanthones such as xanthone, thioxanthone, dimethylthioxanthone, diethylthioxanthone, isopropylthioxanthone;
Cyanines such as thiacarbocyanine, oxacarbocyanine;
Merocyanines such as merocyanine and carbomerocyanine;
Rhodocyanines;
Oxonols;
Thiazines such as thionine, methylene blue and toluidine blue;
Acridines such as acridine orange, chloroflavin, acriflavine;
Acridones such as acridone, 10-butyl-2-chloroacridone;
Anthraquinones such as anthraquinone;
Squariums such as squalium;
Styryls;
Base styryls such as 2- [2- [4- (dimethylamino) phenyl] ethenyl] benzoxazole;
7-diethylamino 4-methylcoumarin, 7-hydroxy 4-methylcoumarin, 2,3,6,7-tetrahydro-9-methyl-1H, 5H, 11H [l] benzopyrano [6.7.8-ij] quinolidine- Coumarins, such as 11-non, etc. are mentioned.

  Of these [C] sensitizers, polycyclic aromatics, xanthones, acridones, styryls, base styryls and coumarins are preferred, polycyclic aromatics and xanthones are more preferred, and 9,10- Dibutoxyanthracene and isopropylthioxanthone are particularly preferred.

  As content of the [C] sensitizer in the said composition, 0.1 mass part-10 mass parts are preferable with respect to 100 mass parts of [A] polymers, and 0.5 mass part-5 mass parts are more. preferable. [D] By making content of a basic compound into the said specific range, a sensitivity can be improved more.

<Other optional components>
In addition to the components [A] to [C], the composition includes [D] a basic compound, [E] a surfactant, and [F] an adhesion assistant as long as the effects of the present invention are not impaired. [G] Other optional components such as a compound having a hindered phenol structure may be contained. These other optional components may be used alone or in combination of two or more. Hereinafter, each component will be described in detail.

<[D] Basic compound>
[D] The basic compound can be arbitrarily selected from those used in chemically amplified resists, for example, aliphatic amine, aromatic amine, heterocyclic amine, quaternary ammonium hydroxide, carboxylic acid quaternary ammonium. Examples include salts. By containing the [D] basic compound in the composition, the diffusion length of the acid generated from the [B] radiation-sensitive acid generator by exposure can be appropriately controlled, and the pattern developability can be improved.

  Examples of the aliphatic amine include trimethylamine, diethylamine, triethylamine, di-n-propylamine, tri-n-propylamine, di-n-pentylamine, tri-n-pentylamine, diethanolamine, triethanolamine, dicyclohexylamine, Examples include dicyclohexylmethylamine.

  Examples of the aromatic amine include aniline, benzylamine, N, N-dimethylaniline, diphenylamine and the like.

  Examples of the heterocyclic amine include pyridine, 2-methylpyridine, 4-methylpyridine, 2-ethylpyridine, 4-ethylpyridine, 2-phenylpyridine, 4-phenylpyridine, N-methyl-4-phenylpyridine, 4 -Dimethylaminopyridine, imidazole, benzimidazole, 4-methylimidazole, 2-phenylbenzimidazole, 2,4,5-triphenylimidazole, nicotine, nicotinic acid, nicotinamide, quinoline, 8-oxyquinoline, pyrazine, pyrazole , Pyridazine, purine, pyrrolidine, piperidine, piperazine, morpholine, 4-methylmorpholine, 1,5-diazabicyclo [4.3.0] -5-nonene, 1,8-diazabicyclo [5.3.0] -7 undecene Etc.

  Examples of the quaternary ammonium hydroxide include tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetra-n-butylammonium hydroxide, tetra-n-hexylammonium hydroxide, and the like.

  Examples of the carboxylic acid quaternary ammonium salt include tetramethylammonium acetate, tetramethylammonium benzoate, tetra-n-butylammonium acetate, and tetra-n-butylammonium benzoate.

  Of these [D] basic compounds, heterocyclic amines are preferable, and 4-dimethylaminopyridine, 4-methylimidazole, and 1,5-diazabicyclo [4.3.0] -5-nonene are more preferable.

  As content of the [D] basic compound in the said composition, 0.001 mass part-1 mass part are preferable with respect to 100 mass parts of [A] polymers, and 0.005 mass part-0.2 mass part. Is more preferable. [D] By making content of a basic compound into the said specific range, pattern developability improves more.

<[E] surfactant>
[E] The surfactant can further improve the film-forming property of the composition. Examples of the surfactant include a fluorine-based surfactant and a silicone-based surfactant. When the said composition contains [E] surfactant, the surface smoothness of a coating film can be improved and the film thickness uniformity of the interlayer insulation film for display elements formed as a result can be improved more.

  As the fluorosurfactant, a compound having a fluoroalkyl group and / or a fluoroalkylene group at at least one of the terminal, main chain and side chain is preferable. For example, 1,1,2,2-tetrafluoro n- Octyl (1,1,2,2-tetrafluoro n-propyl) ether, 1,1,2,2-tetrafluoro n-octyl (n-hexyl) ether, hexaethylene glycol di (1,1,2,2 , 3,3-hexafluoro n-pentyl) ether, octaethylene glycol di (1,1,2,2-tetrafluoro n-butyl) ether, hexapropylene glycol di (1,1,2,2,3,3) -Hexafluoro n-pentyl) ether, octapropylene glycol di (1,1,2,2-tetrafluoro n-butyl) ether, Sodium fluoro n-dodecanesulfonate, 1,1,2,2,3,3-hexafluoro n-decane, 1,1,2,2,3,3,9,9,10,10-decafluoro n- Dodecane, sodium fluoroalkylbenzenesulfonate, sodium fluoroalkylphosphate, sodium fluoroalkylcarboxylate, diglycerin tetrakis (fluoroalkylpolyoxyethylene ether), fluoroalkylammonium iodide, fluoroalkylbetaine, fluoroalkylpolyoxyethylene ether, Fluoroalkyl polyoxyethanol, perfluoroalkyl alkoxylate, carboxylic acid fluoroalkyl ester and the like can be mentioned.

  Examples of commercially available fluorosurfactants include BM-1000, BM-1100 (above, manufactured by BM CHEMIE), MegaFuck F142D, F172, F173, F183, F178, F191, F191, and F471. F476 (above, manufactured by Dainippon Ink and Chemicals), Florard FC-170C, FC-171, FC-430, FC-431 (above, manufactured by Sumitomo 3M), Surflon S-112, S-113, S-131, S-141, S-145, S-382, SC-101, SC-102, SC-103, SC-104, SC-105, SC-105, SC-106 (and above) Asahi Glass Co., Ltd.), F-top EF301, EF303, EF352 (above, manufactured by Shin-Akita Kasei), Footent FT-100, FT-110, FT-140A, FT-150, FT-250, FT-251, FT-300, FT-310, FT-400S, FTX-218, FT-251 (above, Neos), etc. Is mentioned.

  Examples of the silicone-based surfactant include Torre Silicone DC3PA, DC7PA, SH11PA, SH21PA, SH28PA, SH29PA, SH30PA, SH-190, SH-193, SZ-6032, and SF-8428. DC-57, DC-190, SH 8400 FLUID (above, manufactured by Toray Dow Corning Silicone), TSF-4440, TSF-4300, TSF-4445, TSF-4446, TSF-4460, TSF-4252 (above, GE Toshiba Silicone), organosiloxane polymer KP341 (manufactured by Shin-Etsu Chemical Co., Ltd.) and the like.

  The content of the [E] surfactant in the composition is preferably 0.01 parts by mass or more and 2 parts by mass or less, more preferably 0.05 parts by mass with respect to 100 parts by mass of the [A] polymer. Part to 1 part by mass. [E] The film thickness uniformity of a coating film can be improved more by making content of surfactant into the said specific range.

<[F] Adhesion aid>
[F] The adhesion assistant can be used to improve the adhesion between an insulating material and an inorganic substance serving as a substrate, for example, a silicone compound such as silicone, silicone oxide or silicone nitride, gold, copper or aluminum. As the adhesion assistant, a functional silane coupling agent is preferable. Examples of the functional silane coupling agent include a silane coupling agent having a reactive substituent such as a carboxyl group, a methacryloyl group, an isocyanate group, an epoxy group (preferably an oxiranyl group), and a thiol group.

  Examples of the functional silane coupling agent include trimethoxysilylbenzoic acid, γ-methacryloxypropyltrimethoxysilane, vinyltriacetoxysilane, vinyltrimethoxysilane, γ-isocyanatopropyltriethoxysilane, γ-glycidoxypropyltri Examples include methoxysilane, γ-glycidoxypropylalkyldialkoxysilane, γ-chloropropyltrialkoxysilane, γ-mercaptopropyltrialkoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, and the like. Of these, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylalkyldialkoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, and γ-methacryloxypropyltrimethoxysilane are preferred. .

  The content of the [F] adhesion assistant in the composition is preferably 0.5 parts by mass or more and 20 parts by mass or less, and preferably 1 part by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the polymer [A]. More preferred. [F] By setting the content of the adhesion assistant in the specific range, the adhesion between the formed interlayer insulating film for display elements and the substrate is further improved.

<[G] Compound having a hindered phenol structure>
[G] The compound having a hindered phenol structure is a component for preventing cleavage of the bond of the compound by a radical or a peroxide. [G] Examples of the compound having a hindered phenol structure include radical scavengers such as compounds having a hindered amine structure in addition to compounds having a hindered phenol structure.

  Examples of the compound having a hindered phenol structure include pentaerythritol tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], thiodiethylenebis [3- (3,5-di-). tert-butyl-4-hydroxyphenyl) propionate], octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate, tris- (3,5-di-tert-butyl-4-hydroxy Benzyl) -isocyanurate, 1,3,5-trimethyl-2,4,6-tris (3,5-di-tert-butyl-4-hydroxybenzyl) benzene, N, N′-hexane-1,6 -Diylbis [3- (3,5-di-tert-butyl-4-hydroxyphenylpropionamide), 3,3 , 3 ′, 5 ′, 5′-hexa-tert-butyl-a, a ′, a ′-(mesitylene-2,4,6-triyl) tri-p-cresol, 4,6-bis (octylthiomethyl) ) -O-cresol, 4,6-bis (dodecylthiomethyl) -o-cresol, ethylenebis (oxyethylene) bis [3- (5-tert-butyl-4-hydroxy-m-tolyl) propionate, hexamethylene Bis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], 1,3,5-tris [(4-tert-butyl-3-hydroxy-2,6-xylin) methyl] -1,3,5-triazine-2,4,6 (1H, 3H, 5H) -trione, 2,6-di-tert-butyl-4- (4,6-bis (octylthio) -1,3 5-to Azine-2-ylamine) phenol, and the like.

  Examples of the compound having a hindered amine structure include bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis (2,2,6,6-tetramethyl-4-piperidyl) succinate, bis ( 1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, bis (N-octoxy-2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis (N-benzyloxy-2, 2,6,6-tetramethyl-4-piperidyl) sebacate, bis (N-cyclohexyloxy-2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis (1,2,2,6,6) -Pentamethyl-4-piperidyl) 2- (3,5-di-t-butyl-4-hydroxybenzyl) -2-butylmalonate, bis (1-acroyl-2, , 6,6-tetramethyl-4-piperidyl) 2,2-bis (3,5-di-t-butyl-4-hydroxybenzyl) -2-butylmalonate, bis (1,2,2,6, 6-pentamethyl-4-piperidyl) decandioate, 2,2,6,6-tetramethyl-4-piperidyl methacrylate, 4- [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionyl Oxy] -1- [2- (3- (3,5-di-t-butyl-4-hydroxyphenyl) propionyloxy) ethyl] -2,2,6,6-tetramethylpiperidine, 2-methyl-2 -(2,2,6,6-tetramethyl-4-piperidyl) amino-N- (2,2,6,6-tetramethyl-4-piperidyl) propionamide, tetrakis (2,2,6,6- Tetramethyl-4 Compounds such as piperidyl) 1,2,3,4-butanetetracarboxylate, tetrakis (1,2,2,6,6-pentamethyl-4-piperidyl) 1,2,3,4-butanetetracarboxylate It is done.

  As content of the compound which has the [G] hindered phenol structure in the said composition, 0.1 mass part or more and 10 mass parts or less are preferable with respect to 100 mass parts of [A] polymers, and 1.5 mass parts More preferred is 3 parts by mass or less. [G] By setting the content of the compound having a hindered phenol structure in the specific range, the voltage holding ratio of the interlayer insulating film for a display element to be formed is further improved while maintaining the sensitivity of the composition. Can do.

<Method for preparing radiation-sensitive resin composition>
The said composition is prepared in the state melt | dissolved or disperse | distributed by mixing a [A] polymer, a [B] radiation sensitive acid generator, a suitable component as needed, and another arbitrary component in the solvent. For example, the composition can be prepared by mixing each component in a solvent at a predetermined ratio.

  As the solvent, a solvent in which each component is uniformly dissolved or dispersed and does not react with each component is preferably used. Examples of the solvent include alcohols, ethers, glycol ethers, ethylene glycol alkyl ether acetates, diethylene glycol alkyl ethers, propylene glycol monoalkyl ethers, propylene glycol monoalkyl ether acetates, propylene glycol monoalkyl ether propionates, and aromatic hydrocarbons. , Ketones, other esters and the like.

  Examples of alcohols include methanol, ethanol, benzyl alcohol, 2-phenylethyl alcohol, 3-phenyl-1-propanol and the like.

  Examples of ethers include tetrahydrofuran.

  Examples of glycol ethers include ethylene glycol monomethyl ether and ethylene glycol monoethyl ether.

  Examples of the ethylene glycol alkyl ether acetate include methyl cellosolve acetate, ethyl cellosolve acetate, ethylene glycol monobutyl ether acetate, and ethylene glycol monoethyl ether acetate.

  Examples of the diethylene glycol alkyl ether include diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, and diethylene glycol ethyl methyl ether.

  Examples of the propylene glycol monoalkyl ether include propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether and the like.

  Examples of the propylene glycol monoalkyl ether acetate include propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, propylene glycol monobutyl ether acetate and the like.

  Examples of the propylene glycol monoalkyl ether propionate include propylene monoglycol methyl ether propionate, propylene glycol monoethyl ether propionate, propylene glycol monopropyl ether propionate, propylene glycol monobutyl ether propionate and the like. .

  Examples of aromatic hydrocarbons include toluene and xylene.

  Examples of ketones include methyl ethyl ketone, cyclohexanone, 4-hydroxy-4-methyl-2-pentanone, and the like.

  Examples of other esters include methyl acetate, ethyl acetate, propyl acetate, butyl acetate, ethyl 2-hydroxypropionate, methyl 2-hydroxy-2-methylpropionate, ethyl 2-hydroxy-2-methylpropionate, hydroxy Methyl acetate, ethyl hydroxyacetate, butyl hydroxyacetate, methyl lactate, ethyl lactate, propyl lactate, butyl lactate, methyl 3-hydroxypropionate, ethyl 3-hydroxypropionate, propyl 3-hydroxypropionate, butyl 3-hydroxypropionate Methyl 2-hydroxy-3-methylbutanoate, methyl methoxyacetate, ethyl methoxyacetate, propyl methoxyacetate, butyl methoxyacetate, methyl ethoxyacetate, ethyl ethoxyacetate, propyl ethoxyacetate, butyl ethoxyacetate, Methyl ropoxyacetate, ethyl propoxyacetate, propylpropoxyacetate, butyl propoxyacetate, methyl butoxyacetate, ethyl butoxyacetate, propylbutoxyacetate, butylbutoxyacetate, methyl 2-methoxypropionate, ethyl 2-methoxypropionate, 2-methoxypropionate Propyl acid, butyl 2-methoxypropionate, methyl 2-ethoxypropionate, ethyl 2-ethoxypropionate, propyl 2-ethoxypropionate, butyl 2-ethoxypropionate, methyl 2-butoxypropionate, 2-butoxypropionic acid Ethyl, propyl 2-butoxypropionate, butyl 2-butoxypropionate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, propyl 3-methoxypropionate, 3-methyl Butyl xylpropionate, methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate, propyl 3-ethoxypropionate, butyl 3-ethoxypropionate, methyl 3-propoxypropionate, ethyl 3-propoxypropionate, 3-propoxy Examples include propyl propionate, butyl 3-propoxypropionate, methyl 3-butoxypropionate, ethyl 3-butoxypropionate, propyl 3-butoxypropionate, and butyl 3-butoxypropionate.

  Of these solvents, ethylene glycol alkyl ether acetate, diethylene glycol alkyl ether, propylene glycol monoalkyl ether, propylene glycol monoalkyl ether acetate, and butyl methoxyacetate are preferred. Diethylene glycol dimethyl ether, diethylene glycol ethyl methyl ether, propylene glycol monomethyl ether acetate, propylene More preferred are glycol monomethyl ether and butyl methoxyacetate.

<Method for forming interlayer insulating film for display element>
The composition is suitable as a material for forming an interlayer insulating film for a display element. Further, the present invention suitably includes an interlayer insulating film for a display element formed from the composition.

The method for forming an interlayer insulating film for a display element according to the present invention includes:
(1) A step of applying the composition on a substrate to form a coating film,
(2) A step of irradiating at least a part of the coating film with radiation,
(3) a step of developing the coating film irradiated with the radiation; and (4) a step of heating the developed coating film.

  According to the formation method, an interlayer insulating film for a display element that has excellent flatness (remaining film ratio) and does not cause display defects can be formed. In addition, by forming a pattern by exposure, development, and heating using radiation sensitivity, an interlayer insulating film for a display element having a fine and elaborate pattern can be easily formed. Therefore, the formed interlayer insulation film for display elements can be used suitably for display elements, such as a liquid crystal display element and an organic EL display element.

[Step (1)]
In this step, the composition is applied onto a substrate to form a coating film. Preferably, the solvent is removed by prebaking the coated surface.

  Examples of the substrate include glass, quartz, silicone, and resin. Examples of the resin include polyethylene terephthalate, polybutylene terephthalate, polyethersulfone, polycarbonate, polyimide, a ring-opening polymer of cyclic olefin, and a hydrogenated product thereof. As prebaking conditions, although it changes also with kinds, compounding ratios, etc. of each component, it can be set as 70 degreeC-120 degreeC, about 1 minute-10 minutes.

[Step (2)]
In this step, at least a part of the formed coating film is exposed to radiation and exposed. When exposing, it exposes normally through the photomask which has a predetermined pattern. As the radiation used for exposure, radiation having a wavelength in the range of 190 nm to 450 nm is preferable, and radiation containing ultraviolet light of 365 nm is more preferable. Energy of exposure intensity at the wavelength 365nm radiation, by the value measured by luminometer (OAI model356, OAI Optical Ltd. ^Associates), is preferably ^{500J / m 2 ~6,000J / m 2} , 1,500J / m 2 ˜1,800 J / m ² is more preferable.

[Step (3)]
In this step, the coating film irradiated with the radiation is developed. By developing the coated film after exposure, unnecessary portions (radiation irradiated portions) are removed to form a predetermined pattern. As the developer used in the development step, an alkaline aqueous solution is preferable. Examples of the alkali include inorganic alkalis such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, and ammonia; quaternary ammonium salts such as tetramethylammonium hydroxide and tetraethylammonium hydroxide. .

  An appropriate amount of a water-soluble organic solvent such as methanol or ethanol, or a surfactant can be added to the alkaline aqueous solution. The concentration of alkali in the aqueous alkali solution is preferably from 0.1% by mass to 5% by mass from the viewpoint of obtaining appropriate developability. Examples of the developing method include a liquid piling method, a dipping method, a rocking dipping method, and a shower method. The development time varies depending on the composition of the composition, but is about 10 seconds to 180 seconds. Subsequent to such development processing, for example, washing with running water is performed for 30 seconds to 90 seconds, and then a desired pattern can be formed by, for example, air drying with compressed air or compressed nitrogen.

[Step (4)]
In this step, the developed coating film is heated. For heating, a heating device such as a hot plate or an oven is used to heat the patterned thin film, thereby promoting the curing reaction of the [A] polymer and obtaining a cured product. As heating temperature, it is about 120 to 250 degreeC, for example. The heating time varies depending on the type of heating device, but for example, it is about 5 to 30 minutes for a hot plate and about 30 to 90 minutes for an oven. Moreover, the step baking method etc. which perform a heating process 2 times or more can also be used. In this way, a patterned thin film corresponding to the target display element interlayer insulating film can be formed on the surface of the substrate. Note that the use of the cured film is not limited to the interlayer insulating film for display elements, and can also be used as a spacer or a protective film.

  The film thickness of the formed interlayer insulation film for display elements is preferably 0.1 μm to 8 μm, more preferably 0.1 μm to 6 μm, and particularly preferably 0.1 μm to 4 μm.

  EXAMPLES Hereinafter, although this invention is explained in full detail based on an Example, this invention is not interpreted limitedly based on description of this Example.

<[A] Synthesis of polymer>
[Synthesis Example 1]
A flask equipped with a condenser and a stirrer was charged with 7 parts by mass of 2,2′-azobis (2,4-dimethylvaleronitrile) and 200 parts by mass of diethylene glycol ethyl methyl ether. Subsequently, 5 parts by mass of methacrylic acid, 25 parts by mass of the compound (Z-1) represented by the following formula giving structural unit (I), 30 parts by mass of glycidyl methacrylate giving structural unit (II), and structural unit (III) 2 parts by weight of 2-tetrahydropyranyl methacrylate giving 5 parts, 5 parts by weight of styrene giving 10 parts by weight of 2-hydroxyethyl methacrylate and 3 parts by weight of α-methylstyrene dimer as a molecular weight regulator After purging with nitrogen, stirring was started gently. The temperature of the solution was raised to 70 ° C., and this temperature was maintained for 5 hours to obtain a polymer solution containing the copolymer (A-1). Mw of the copolymer (A-1) was 9,000. The solid content concentration of the polymer solution was 33.6% by mass.

[Synthesis Example 2]
A flask equipped with a condenser and a stirrer was charged with 7 parts by mass of 2,2′-azobis (2,4-dimethylvaleronitrile) and 200 parts by mass of diethylene glycol ethyl methyl ether. Subsequently, 30 parts by mass of (Z-1) giving structural unit (I), 30 parts by mass of glycidyl methacrylate giving structural unit (II), and 20 parts by mass of 1-n-butoxyethyl methacrylate giving structural unit (III) And 5 parts by mass of methacrylic acid, 5 parts by mass of styrene and 10 parts by mass of 2-hydroxyethyl methacrylate, and 3 parts by mass of α-methylstyrene dimer as a molecular weight modifier, giving nitrogen and other structural units, Stirring was started gently. The temperature of the solution was raised to 70 ° C., and this temperature was maintained for 5 hours to obtain a polymer solution containing the copolymer (A-2). Mw of the copolymer (A-2) was 10,000. The solid content concentration of the polymer solution was 31.5% by mass.

[Synthesis Example 3]
A flask equipped with a condenser and a stirrer was charged with 7 parts by mass of 2,2′-azobis (methyl 2-methylpropionate) and 200 parts by mass of propylene glycol monomethyl ether acetate. Subsequently, 50 parts by mass of the compound (Z-2) represented by the following formula that gives the structural unit (I) and 35 parts by mass of benzyl methacrylate and 15 parts by mass of methacrylic acid that give other structural units were charged and substituted with nitrogen. , Began stirring gently. The temperature of the solution was raised to 80 ° C., and this temperature was maintained for 6 hours to obtain a polymer solution containing the copolymer (A-3). Mw of the copolymer (A-3) was 10,000. The solid content concentration of the polymer solution was 30.5% by mass.

[Synthesis Example 4]
A flask equipped with a condenser and a stirrer was charged with 7 parts by mass of 2,2′-azobis (2,4-dimethylvaleronitrile) and 200 parts by mass of diethylene glycol ethyl methyl ether. Subsequently, 52 parts by mass of glycidyl methacrylate giving structural unit (II) and 48 parts by mass of benzyl methacrylate giving other structural units were charged and purged with nitrogen, and then gently stirring was started. The temperature of the solution was raised to 80 ° C., and this temperature was maintained for 6 hours to obtain a polymer solution containing a copolymer (CS-1). The Mw of the copolymer (CS-1) was 10,000. The solid content concentration of the polymer solution was 32.3% by mass.

[Synthesis Example 5]
A flask equipped with a condenser and a stirrer was charged with 7 parts by mass of 2,2′-azobis (2,4-dimethylvaleronitrile) and 200 parts by mass of diethylene glycol ethyl methyl ether. Subsequently, 25 parts by weight of glycidyl methacrylate giving structural unit (II), 55 parts by weight of 1-cyclohexyloxyethyl methacrylate giving structural unit (III), and 5 parts by weight of methacrylic acid giving other structural units, 5 parts by weight of styrene Then, 10 parts by mass of 2-hydroxyethyl methacrylate and 3 parts by mass of α-methylstyrene dimer as a molecular weight modifier were charged and purged with nitrogen, and then gently stirred. The temperature of the solution was raised to 70 ° C., and this temperature was maintained for 5 hours to obtain a polymer solution containing a copolymer (CS-2). Mw of the copolymer (CS-2) was 9,000. The solid content concentration of the polymer solution was 32.1% by mass.

[Synthesis Example 6]
A flask equipped with a condenser and a stirrer was charged with 7 parts by mass of 2,2′-azobis (methyl 2-methylpropionate) and 200 parts by mass of propylene glycol monomethyl ether acetate. Subsequently, 50 parts by mass of 1-cyclohexyloxyethyl methacrylate giving structural unit (III) and 35 parts by mass of benzyl methacrylate and 15 parts by mass of methacrylic acid giving other structural units were charged with nitrogen, and then gently stirred. I started. The temperature of the solution was raised to 80 ° C., and this temperature was maintained for 6 hours to obtain a polymer solution containing a copolymer (CS-3). The Mw of the copolymer (CS-3) was 10,000. The solid content concentration of the polymer solution was 30.5% by mass.

<Preparation of radiation-sensitive resin composition>
Hereinafter, the components used for the preparation of the radiation sensitive resin compositions of Examples and Comparative Examples will be described in detail.

[B] Radiation sensitive acid generator B-1: 4,7-di-n-butoxy-1-naphthyltetrahydrothiophenium trifluoromethanesulfonate B-2: N-hydroxynaphthalimide-trifluoromethanesulfonic acid ester B- 3: (5-Propylsulfonyloxyimino-5H-thiophen-2-ylidene)-(2-methylphenyl) acetonitrile (Ciba Specialty Chemicals, IRGACURE PAG 103)

[C] Sensitizer C-1: Isopropylthioxanthone C-2: 9,10-dibutoxyanthracene

[D] Basic compound D-1: 4-dimethylaminopyridine D-2: 4-methylimidazole

[E] Surfactant E-1: Silicone surfactant (made by Toray Dow Corning Silicone, SH 8400 FLUID)
E-2: Fluorosurfactant (manufactured by Neos, Factent FTX-218)

[F] Adhesion aid F-1: γ-glycidoxypropyltrimethoxysilane F-2: β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane F-3: γ-methacryloxypropyltrimethoxysilane

[Example 1]
[A] A solution containing (A-1) as a polymer (an amount corresponding to 100 parts by mass (solid content) of (A-1)) and [B] (B-1 as a radiation-sensitive acid generator) ) 3.5 parts by mass, [D] 0.01 parts by mass as a basic compound, [E] 0.2 parts by mass of (E-1) as a surfactant and [F] adhesion A radiation-sensitive composition was prepared by mixing 3.0 parts by mass of (F-1) as an auxiliary agent and filtering through a membrane filter having a pore size of 0.2 μm.

[Examples 2 to 7 and Comparative Examples 1 and 2]
Each composition was prepared in the same manner as in Example 1 except that the type and amount of each component were as described in Table 1. In Table 1, “-” means that the corresponding component was not used.

<Evaluation>
The following evaluation was implemented using each prepared composition. The results are shown in Table 1.

[Sensitivity (J / m ² )]
Hexamethyldisilazane (HMDS) was applied on a 550 × 650 mm chromium-deposited glass and heated at 60 ° C. for 1 minute. Each composition was applied onto the chromium-deposited glass after the HMDS treatment using a slit die coater (manufactured by Tokyo Ohka Kogyo Co., Ltd., TR6322105-CL), and the ultimate pressure was set to 100 Pa, and the solvent was removed under vacuum. Thereafter, it was further pre-baked at 90 ° C. for 2 minutes to form a coating film having a thickness of 3.0 μm. Subsequently, using an exposure machine (manufactured by Canon, MPA-600FA), after irradiating the coating film with the exposure amount as a variable amount through a mask having a 60 μm line and space (10 to 1) pattern, Development was performed by a puddle method at 25 ° C. with a 0.4 mass% tetramethylammonium hydroxide solution. The development time was 80 seconds. Next, washing with running ultrapure water for 1 minute was performed, followed by drying to form a pattern on the chromium-deposited glass substrate after the HMDS treatment. At this time, the exposure amount necessary for completely dissolving the 6 μm space pattern was examined. When this value was 480 (J / m ² ) or less, it was judged that the sensitivity was good.

[Residual film rate (%)]
A coating film was formed on the silicon substrate by operating in the same manner as in the sensitivity evaluation. Without being exposed, this silicon substrate was heated in a clean oven at 220 ° C. for 1 hour to obtain a cured film. The film thickness before and after heating was measured using a laser microscope (VK-8500, manufactured by Keyence). The residual film ratio (%) was determined from this value and the following formula.
Residual film ratio (%) = (film thickness after heating / film thickness before heating) × 100
When the remaining film rate was less than 70%, the remaining film rate was determined to be defective.

[surface hardness]
A coating film was formed on the silicon substrate by operating in the same manner as in the sensitivity evaluation. Without being exposed, this silicon substrate was heated in a clean oven at 220 ° C. for 1 hour to obtain a cured film. About the board | substrate which has this cured film, the pencil hardness (surface hardness) of the cured film was measured by the 8.4.1 pencil scratch test of JISK-5400-1990. When this value is 3H or more, it can be said that the surface hardness as the interlayer insulating film for display elements is good, and it has sufficient curability.

[Solvent resistance (%)]
A coating film was formed on the silicon substrate by operating in the same manner as in the sensitivity evaluation. Without being exposed, this silicon substrate was heated in a clean oven at 220 ° C. for 1 hour to obtain a cured film. About the board | substrate which has this cured film, the film thickness (T1) of the obtained cured film was measured using the laser microscope (VK-8510, product made from Keyence). Next, the silicon substrate on which this cured film was formed was immersed in dimethyl sulfoxide whose temperature was controlled at 70 ° C. for 20 minutes, and then the thickness (t1) of the cured film was measured. The rate of change in thickness (%) was determined and defined as solvent resistance (%).
Solvent resistance (%) = {(t1-T1) / T1} × 100
When the absolute value of this value was less than 5%, the solvent resistance was judged to be excellent.

[Voltage holding ratio]
Each radiation sensitive resin composition was spin-coated on a soda glass substrate on which a SiO ₂ film for preventing elution of sodium ions was formed on the surface, and an ITO (indium-tin oxide alloy) electrode was deposited in a predetermined shape. Thereafter, prebaking was performed for 10 minutes in a clean oven at 90 ° C. to form a coating film having a thickness of 2.0 μm. Next, the coating film was exposed at an exposure amount of 500 J / m ² without using a photomask. Thereafter, the coating film was cured by post-baking at 230 ° C. for 30 minutes. Next, the substrate on which the pixels are formed and the substrate on which the ITO electrode is simply deposited in a predetermined shape are bonded together with a sealing agent mixed with 0.8 mm glass beads, and then Merck liquid crystal MLC6608 is injected into the liquid crystal. A cell was produced. Further, the liquid crystal cell was placed in a constant temperature layer at 60 ° C., and the voltage holding ratio of the liquid crystal cell was measured by a liquid crystal voltage holding ratio measuring system (VHR-1A type, Toyo Technica Co., Ltd.). The applied voltage at this time is a square wave of 5.5 V, and the measurement frequency is 60 Hz. The voltage holding ratio (%) is a value obtained from the following formula.
Voltage holding ratio (%) = (potential difference of liquid crystal cell after 16.7 milliseconds / voltage applied at 0 milliseconds) × 100
If the voltage holding ratio of the liquid crystal cell is 90% or less, it means that the liquid crystal cell cannot hold the applied voltage at a predetermined level for a time of 16.7 milliseconds, and the liquid crystal cannot be sufficiently aligned. There is a high risk of causing "burn-in".

  As is apparent from the results of Table 1, Examples 1 to 7 using the composition have a good sensitivity as compared with the compositions of Comparative Examples 1 and 2, and in addition to the surface hardness and solvent resistance, It was found to have excellent flatness (remaining film ratio). Moreover, Examples 1-7 which used the said composition were also high also about the voltage retention, and it turned out that it is hard to cause a display defect.

  The radiation-sensitive resin composition of the present invention has good sensitivity, has excellent flatness (residual film ratio) in addition to surface hardness and solvent resistance, and does not cause display defects. An interlayer insulating film can be formed. Therefore, the composition is suitable as a material for forming an interlayer insulating film for a display element such as a liquid crystal display element or an organic EL display element.

Claims (6)

[A] a polymer containing a structural unit (I) having a group represented by the following formula (1), and [B] a radiation-sensitive acid generator ,
[A] A radiation-sensitive resin composition, wherein the polymer is obtained by radical polymerization of one or more monomers including a monomer that provides the structural unit (I) .

(In formula (1), R ¹ and R ² are each independently a hydrogen atom, an alkyl group, a cycloalkyl group or an aryl group, provided that the hydrogen atom of the alkyl group, cycloalkyl group and aryl group is Some or all of them may be substituted, and R ¹ and R ² are not both hydrogen atoms, and R ³ is a single bond, a methylene group, an alkylene group, an arylene group, or a group represented by the following formula (4 ) is a divalent organic group comprising a combination of a group represented by or these groups. However, some or all of the hydrogen atoms with these groups may .R ⁴ be substituted, epoxy group, a glycidyl group, an alicyclic group, a vinyl group or (meth) acryloyl group having a glycidyl group, unsaturated double bond or epoxy group. However, or part of the hydrogen atoms of the epoxy group has Parts are optionally substituted .n is an integer of 1 to 3. However, if R ⁴ is plural, the plurality of R ⁴ may be be the same or different.)

(In Formula (4), a and c are each independently an integer of 1 to 6. b is an integer of 1 to 2.)
  [A] The polymer further comprises a structural unit (II) having an epoxy group in a polymer molecule containing the structural unit (I) or in another polymer molecule not containing the structural unit (I). Item 2. The radiation-sensitive resin composition according to Item 1.   [C] The radiation sensitive resin composition according to claim 1 or 2, further comprising a sensitizer.   The radiation sensitive resin composition according to claim 1, 2 or 3, which is used for forming an interlayer insulating film for a display element. (1) The process of apply | coating the radiation sensitive resin composition of Claim 4 on a board | substrate, and forming a coating film,
(2) A step of irradiating at least a part of the coating film with radiation,
(3) A method of forming an interlayer insulating film for a display element, comprising: a step of developing the coating film irradiated with the radiation; and (4) a step of heating the developed coating film.   The interlayer insulation film for display elements formed from the radiation sensitive resin composition of Claim 4.