WO2006016648A1 - Star polymer, acid-decomposable resin composition, resist composition and di(meth)acrylate compound - Google Patents

Abstract

Disclosed is a star polymer having a core portion derived from a compound represented by the following formula (I): (I) (wherein R1 and R2 respectively represent a hydrogen atom or an alkyl group having 1-4 carbon atoms; A represents a divalent or higher-valent organic linking group having no acetal structure; B represents a divalent or higher-valent organic linking group having an acetal structure or a ketal structure; and n1-n4 respectively represent an integer of not less than 1). The star polymer has an acetal structure which is thermally stable and can be easily mass-produced, and is readily cleavable by an acid.

Description

 Star polymer, acid-decomposable resin composition, resist composition, and di (meth) acrylate compound

 Technical field

 [0001] The present invention has a structure that can be easily cleaved by an acid and is suitable for a resist material and the like, a novel star polymer, an acid-decomposable resin composition and a resist composition containing the star polymer, and a star The present invention relates to a compound of di (meth) attateroi toy useful as a raw material for polymer production.

 This application claims priority based on Japanese Patent Application No. 2004-235905 filed on August 13, 2004, the contents of which are incorporated herein by reference.

 Background art

 [0002] Conventionally, as a star polymer having an acetal structure in a molecule and having a property of being cleaved by an acid, a star-type polymetatalate induced by dimethatare toy compound force represented by the following formula has been known. (Patent Document 1).

 However, since this compound is thermally unstable, it is difficult to carry out purification such as distillation, and there is a problem in industrial mass production.

 [0003] [Chemical 1]

 [0004] Patent Document 1: US Pat. No. 6,323, 360

 Disclosure of the invention

 Problems to be solved by the invention

[0005] The present invention has been made in view of the above-mentioned problems of the prior art, and is derived from a poly (meth) atrelate toy compound having an acetal structure that is considered to be thermally stable and easy to mass-produce. This new star polymer, which is derived and has the property of being easily cleaved by acid It is an object of the present invention to provide an acid-decomposable resin composition and resist composition containing a mer, and a novel di (meth) ataretoy compound useful as a raw material for producing a star polymer. Means for solving the problem

 [0006] As a result of intensive studies to solve the above problems, the present inventors have determined that a (meth) acrylic acid portion and at least one acetal structure portion cleaved with an acid are thermally stable. We have succeeded in synthesizing di (meth) attareito toy compounds linked via a ru chain. And this di (meth) attalei toy compound is thermally stable and easy to mass-produce, and by using this di (meth) atreatoi compound, it can be easily cleaved by acid. The present inventors have found that a novel star polymer having such properties can be easily obtained, and has completed the present invention.

 [0007] According to the first aspect of the present invention, the following star polymers (1) to (14) are provided.

 (1) Formula (I)

[0008] [Chemical 2]

(I)

ιι4

(Wherein R ¹ and R ² each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, 、 represents a divalent or higher valent organic linking group not containing an acetal structure, and B represents an acetal structure. Represents a divalent or higher valent organic linking group or an organic linking group which forms an acetal structure together with an ester oxygen atom, and nl to! Ι4 each independently represents an integer of 1 or more, nl when but 2 or more, when Yogu n2 be R ¹ each other have the same or different are 2 or more, when Yogu n3 be the or different in each of R ¹ each other and a with each other the same is 2 or more, R ² may be the same or different. When n4 is 2 or more, R ² and B may be the same or different, respectively. A star polymer characterized by having a part.

[0009] (2) The star polymer of (1), wherein in the formula (I), A is a hydrocarbon group having 2 or more carbon atoms and 2 or more valences.

(3) In the above formula (I), A is an alkylene group having 2 or more carbon atoms (1) or (1) 2) Star polymer.

 (4) In the formula (I), B is the formula (II)

 [0010] [Chemical 3]-· · (II)

[Wherein R ¹¹ and R ¹² each independently represents a hydrogen atom or an organic group, and A ¹ represents a divalent or higher organic linking group], or the above-mentioned (1) to (3) V, any star polymer characterized by being a functional group having a functional group represented by formula (II) in a partial structure

(5) In the formula (I), B is the formula (III)

[0012] [Chemical 4] '· · · (I I I)

(Wherein R ^{U to} R ¹⁴ each independently represents a hydrogen atom or an organic group, A ¹ and A ² each independently represent a divalent or higher valent organic linking group, ml Represents an integer greater than or equal to 1. When ml is 2 or more, R ¹³ , R ¹⁴ and A ² may be the same or different from each other. (1) to (3) V, which is a star polymer, characterized in that it is a functional group having a functional group represented by) in a partial structure.

[0014] (6) The star polymer of (5), wherein in the formula (III), A ¹ and A ² are each independently a divalent or higher valent hydrocarbon group.

(7) In the formula (III), A ¹ and A ² are each independently a chain alkylene group, a cycloalkylene group, or a cycloalkylalkylene group. One positive mer.

 (8) The compound represented by the formula (I) is represented by the formula (IV)

[0015] [Chemical 5]

(Wherein R ¹ and R ² each independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and R ^{21 to} R ²⁴ each independently represents a hydrogen atom or an organic group) It represents, a ^11, a ¹² and a ^{1 3} each independently represents a divalent organic linking group.) and feature that is a compound represented by (1) the star polymer.

(9) The star polymer according to (8), wherein in the formula (IV), A ¹¹ and A ¹³ are each independently a divalent organic linking group having 2 or more carbon atoms.

(10) The star polymer according to (8), wherein in formula (IV), A ¹¹ and A ¹³ are each independently a divalent hydrocarbon group having 2 or more carbon atoms.

(11) The star polymer of (8), wherein in the formula (IV), A ¹¹ and A ¹³ are each independently an alkylene group having 2 or more carbon atoms.

(12) The star polymer according to any one of (8) to (11), wherein A ¹² in the formula (IV) is a divalent hydrocarbon group.

(13) The star polymer according to any one of (8) to (12), wherein in the formula (IV), A ¹² is a chain alkylene group, a cycloalkylene group or a cycloalkylalkylene group.

(14) The star polymer according to any one of (1) to (13), wherein the ester oxygen atom does not include a partial structure in which the ester oxygen atom is part of the acetal structure.

 [0018] According to the second aspect of the present invention, the following acid-decomposable rosin compositions (15) and (16) are provided. (15) An acid-decomposable resin composition comprising any one of the above (1) to (14).

 (16) The acid-decomposable rosin composition according to (15), further comprising a compound that generates an acid in response to an external stimulus.

According to a third aspect of the present invention, there is provided a resist composition comprising the star polymer of any one of the above (1) to (14) and a compound that generates an acid in response to an external stimulus. Provided. According to a fourth aspect of the present invention, there is provided the di (meth) acrylate compound of any one of the following (17) to (21).

 (17) Formula (V)

 [0020] [6]

(Wherein R ¹ and R ² each independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and R ^{31 to} R ³⁴ each independently represents a hydrogen atom or an organic group) A ²¹ and A ^{23 each} independently represents a divalent organic linking group, and A ²² represents a divalent organic linking group having an alicyclic skeleton. (Meth) atalylate compounds.

(18) In the above formula (V), A ²¹ and A ²³ are each independently a divalent organic linking group having 2 or more carbon atoms. .

(19) In the above formula (V), A ²¹ and A ²³ are each independently a divalent hydrocarbon group having 2 or more carbon atoms, Atarylate compound.

(20) In the above formula (V), A ²¹ and A ²³ are each independently an alkylene group having 2 or more carbon atoms, The di (meth) acrylate compound of (17),

(21) The formula (V), wherein A ²² is a cycloalkylene group or a cycloalkylalkylene group (17) to (20) V, any of the di (meth) acrylate compounds.

 The invention's effect

 [0023] The star polymer of the present invention is obtained by polymerizing a poly (meth) atreatoi compound having a thermally stable structure, and has a structure that can be easily cleaved by an acid. It is useful as a resist material.

 The acid-decomposable resin composition and the resist composition of the present invention contain the star polymer of the present invention having a structure that can be easily cleaved by an acid, and are useful as a highly sensitive resist resin composition. is there.

By using the di (meth) attale toy compound of the present invention, monomers are also derived from the monomers. The derived polymer can also be improved in thermal stability while maintaining the property of being easily cleaved by an acid, and can be industrially produced in large quantities.

 BEST MODE FOR CARRYING OUT THE INVENTION

 Hereinafter, the present invention will be described in detail.

 1) Monomer for constituting the core

 The star polymer of the present invention is characterized by having a core part induced by the compound force represented by the formula (D). That is, the compound represented by the formula (I) is a core of the star polymer of the present invention. It is a monomer for constituting the part.

In the formula (I), R ¹ and R ² are each independently a hydrogen atom; or carbon such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a t-butyl group, etc. Represents an alkyl group of 1 to 4;

 [0026] A represents a divalent or higher valent organic linking group that does not include an acetal structure.

 A is not particularly limited as long as it is a divalent or higher valent organic group that does not contain an acetal structure and connects an ester oxygen atom and B, and is stable under polymerization reaction conditions. It is preferably a divalent or higher valent hydrocarbon group.

[0027] The hydrocarbon group having 2 or more carbon atoms and 2 or more valences of A includes (a) an alkylene group having 2 or more carbon atoms, (b) an alkyleneoxy group having 2 or more carbon atoms, (c) an arylene. (D) an aryleneoxy group, (e) an aryl atom which may have an oxygen atom, (f) a carbon atom having a trivalent or higher carbon number of 2 or more, which may have an oxygen atom. A hydrogen group etc. are mentioned.

 Moreover, these groups may have an unsaturated bond in a part thereof.

[0028] (a) an alkylene group having 2 or more carbon atoms

 Examples of the alkylene group having 2 or more carbon atoms include a chain alkylene group having 2 or more carbon atoms, a cycloalkylene group, and a cycloalkylalkylene group.

 A chain alkylene group having 2 or more carbon atoms is represented by the following chemical formula (7).

[0029] [Chemical 7]

[0030] In the above formula, Ra and Rb each independently represent a hydrogen atom; or an alkyl group having 1 to 4 carbon atoms such as a methyl group, an ethyl group, and an isopropyl group, and p is an integer of 2 or more, preferably Represents an integer of 2 to 10, more preferably an integer of 2, 3, or 4. Further, the repeating units: —C (Ra) (Rb) — may be the same as or different from each other.

 [0031] Specific examples of the chain alkylene group having 2 or more carbon atoms include an ethylene group, a propylene group, a trimethylene group, a tetramethylene group, a pentamethylene group, and a hexamethylene group.

 [0032] The cycloalkylene group may be a monocyclic cycloalkylene group or a polycyclic cycloalkylene group as long as the group has two bonds extending from the carbon atom of the cycloalkyl ring. May be. Examples of the cycloalkyl ring include a cyclopentane ring, a cyclohexane ring, a cycloheptane ring, a cyclooctane ring, an adamantane ring, and a norbornane ring.

 Preferred examples of the cycloalkylene group include the following groups.

[0033] [Chemical 8]

[0034] The cycloalkylalkylene group is not particularly limited as long as it has a structure in which an alkylene group is bonded to a carbon atom of a cycloalkyl ring. Examples of the cycloalkyl ring include those described above.

 Preferable examples of the cycloalkylalkylene group include the following groups.

 [0035] [Chemical 9]

[0036] (b) an alkyleneoxy group having 2 or more carbon atoms Examples of the alkyleneoxy group having 2 or more carbon atoms include (i) chain alkyleneoxy group, GO cycloalkyleneoxy group, () cycloalkylalkyleneoxy group, and the like.

[0037] Examples of the chain alkyleneoxy group (i) include the following groups.

 [0038] [Chemical 10]

(In the formula, q represents an integer of 1 or more, preferably an integer of 1 to 20, more preferably an integer of 1, 2, or 3. When q is 2 or more, the formula: —CH 2 CH 2 O The groups represented by — are identical to each other.

 twenty two

 May be different from each other. )

 Examples of the cycloalkyleneoxy group of (ii) include the following groups.

[0040] [Chemical 11]

[0041] (iii) 'As the group, the following groups can be exemplified. [0042] [Chemical 12]

 [0043] (c) arylene group

 The arylene group is not particularly limited as long as it has a divalent or higher valent aromatic group. Specific examples of the arylene group include the following groups.

[0044] [Chemical 13]

[0045] (d) aryleneoxy group

 Specific examples of the aryleneoxy group include the following groups.

[0046] [Chem. 14]

 (e) It has an oxygen atom!

Specific examples of the arylalkylene group which may have an oxygen atom include the following. [0048] [Chemical 15]

[0049] (f) Oxygen atom! / Also good! Trivalent hydrocarbon group having 2 or more carbon atoms

 Examples of the trivalent or higher hydrocarbon group having 2 or more carbon atoms which may have an oxygen atom include a group having a chain structure shown in Chemical Formula 16 below, a chain structure and an aromatic group shown in Chemical Formula 17 and Chemical Formula 18 below. Examples include groups in which group groups are combined.

[0050] [Chemical 16]

[0052] [Chemical 18]

 [0053] These hydrocarbon groups having 2 or more carbon atoms and 2 or more carbon atoms may have a substituent at an arbitrary position. Examples of the substituent include an alkyl group such as a methyl group, an ethyl group, a propyl group, and an isopropyl group; an alkoxy group such as a methoxy group, an ethoxy group, a propoxy group, and a t-butoxy group; a halogen atom such as a fluorine atom and a chlorine atom; Can be mentioned.

 [0054] Among these, the A is more preferably a divalent chain alkylene group having 2 or more carbon atoms, which is preferably an alkylene group having 2 or more carbon atoms of (a). Particularly preferred is a divalent chain alkylene group having 2 to 10 carbon atoms! /.

 [0055] B represents a divalent or higher-valent organic linking group having an acetal structure. In the present invention, the acetal structure is obtained by reacting a dialkoxy compound obtained by reacting an aldehyde and an alcohol in the presence of an acid catalyst, or reacting a ketone and an alcohol in the presence of an acid catalyst. The structure of the resulting dialkoxy compound!

 [0056] B is not particularly limited as long as it has at least acetal structure and is a divalent or higher-valent organic group that links the ester oxygen atom and A. B may be an organic linking group that forms an acetal structure with an ester oxygen atom.

 Among these, as B, the following formula (II)

 [0057] [Chemical Formula 19] 1 0 12 Functional group represented by P-A (II) or the following formula (π ′)

— O— C (R ⁿ ) (R ¹² ) — · '· (Π,)

Or a functional group represented by the above formula (Π) or the above formula (′). Formula (III) is preferably a functional group possessed by the structure

[0059] [Chemical 20] '·-(I I I)

 [0060] or a functional group having a functional group represented by the formula (部分) in the partial structure is more preferable.

In the above formulas (Π), (Π ′), (III), R ^{U to} R ¹⁴ each independently represents a hydrogen atom or an organic group.

The organic group may have, for example, an alkyl group such as a methyl group, an ethyl group, a propyl group, or an isopropyl group; a substituent such as a phenyl group, a 4-chlorophenyl group, or a 4-methylphenol group. Good phenol groups; alkoxycarbonyl groups such as methoxycarbon groups and ethoxycarbonyl groups; alkoxy groups such as methoxy groups, ethoxy groups, and propoxy groups; alkyl groups such as methylsulfonyl groups and ethenoresnorephenol groups Norequinoles norephoro-nore group; aryl-sulfol groups such as phenol-nolesnorehoninole group, 4-chlorophenol sulfole group; and the like. Among these, R ^{U to} R ¹⁴ are preferably each independently an alkyl group.

[0062] A ¹ and A ² each independently represent a divalent or higher valent organic linking group, but in the present invention, A ¹ and A ² each independently represent a divalent or higher valent hydrocarbon. A group is preferably each independently and more preferably a chain alkylene group, a cycloalkylene group or a cycloalkylalkylene group.

[0063] The divalent or more hydrocarbon groups of A ¹ and A ^2, chain alkylene group, specific examples of the cycloalkylene group and cycloalkyl alkylene groups, divalent or polyvalent hydrocarbon group of the A, chain Examples thereof are the same as those exemplified as the alkylene group, cycloalkylene group and cycloalkylalkylene group.

[0064] In addition, ml represents an integer of 1 or more, preferably represents an integer of 1 to 5, and more preferably represents an integer of 1, 2, or 3. When ml is 2 or more, the groups represented by the formula: OC (R ¹³ ) (R ¹⁴ ) O—A ² ) — may be the same or different.

[0065] In the formula (I), nl to n4 each independently represents an integer of 1 or more, and nl is 2 or more. R ¹ may be the same or different. When n2 is 2 or more, R ¹ and A may be the same or different. When n3 is 2 or more, R ² are May be the same or different. When n4 is 2 or more, R ² and B may be the same or different.

 In the present invention, the compound represented by the formula (I) is particularly preferably a compound represented by the formula (IV).

 [0066] [Chemical 21]

In Formula (IV), R ¹ and R ² represent the same meaning as described above, and ¹ to R ²⁴ each independently represent a hydrogen atom or an organic group. Specific examples of the organic group of R ^{21 to} R ²⁴ include the same as those listed as specific examples of the organic group of R ^{U to} R ¹⁴ . A ¹¹ , A ¹² and A ¹³ each independently represent a divalent organic linking group. Specific examples of the divalent organic linking group of A ¹¹ , A ¹² and A ¹³ include the same as those listed as specific examples of the divalent organic linking group of AA ² .

In the above formula (IV), it is preferable that A ¹¹ and A ¹³ are each independently a divalent organic linking group having 2 or more carbon atoms, and each independently is a divalent having 2 or more carbon atoms. The hydrocarbon group is more preferably an alkylene group having 2 or more carbon atoms, more preferably each independently.

In the formula (IV), A ¹² is more preferably a chain alkylene group, a cycloalkylene group, or a cycloalkylalkylene group, preferably a divalent hydrocarbon group.

 [0069] Specific examples of the compound represented by the formula (I) are listed below. Of course, in the present invention, the compound represented by the formula (I) is not limited to the following.

[0070] [Chemical 22]

[0071] [Chemical 23]

[0072] (In the formula, n represents an arbitrary natural number.)

 In the present invention, it is preferable that the formula (I) does not include a partial structure in which the ester oxygen atom is a part of the acetal structure.

[0073] Among the compounds represented by the formula (I), the compound represented by the formula (V)

[0074] [Chemical 24]

(V)

 The compound represented by [0075] is a novel compound. The compound represented by the formula (V) is thermally stable, easily purified, and easily industrially mass-produced. The compound represented by the formula (V) is particularly useful as a raw material for producing the star polymer of the present invention.

In the above formula (V), R ¹ and R ² represent the same meaning as described above.

 34 31 34

R ³¹ to ⁴ each independently represent a hydrogen atom or an organic group. ¹ to ⁴ of the organic group Specific examples of these include those listed as specific examples of the organic groups of R ^{U to} R ¹⁴ .

[0077] A ²¹ and A ²³ each independently represent a divalent organic linking group, and A ²² represents a divalent organic linking group having an alicyclic skeleton.

Specific examples of the divalent organic linking group of A ²¹ and A ²³ include the same as those listed as specific examples of the divalent organic linking group of AA ² .

In the present invention, it is preferable that in formula (V), A ²¹ and A ²³ are each independently a divalent organic linking group having 2 or more carbon atoms. More preferably, it is a divalent hydrocarbon group having 2 or more carbon atoms, more preferably each independently a divalent alkylene group having 2 or more carbon atoms. Examples of the alkylene group having 2 or more carbon atoms of A ²¹ and A ²³ include an ethylene group, a propylene group, a trimethylene group, a tetramethylene group, and a pentamethylene group.

[0079] Examples of the divalent organic linking group having an alicyclic skeleton of A ²² include a cycloalkylene group, a cycloanolenoanolylene group, a cycloanolylene xylene group, and a cycloanolequinolenoylene xylene group. Etc. Specific examples thereof are the same as those listed as specific examples of the cycloalkylene group, cycloalkylalkylene group, cycloalkyleneoxy group and cycloalkylalkyleneoxy group of A.

In the present invention, in the formula (V), A ²² is preferably a cycloalkylene group or a cycloalkylanolylene group.

[0080] 2) Star polymer

 The star polymer of the present invention has a core part derived from the compound represented by the formula (I) (hereinafter abbreviated as “compound (1)”).

 In the star polymer of the present invention, if the polymer derived from the compound (I) is a core part, the repeating unit constituting the arm part is not particularly limited.

 [0081] Specific examples of the repeating unit constituting the arm part include addition-polymerizable unsaturated groups such as (meth) acrylic acid esters, (meth) acrylamides, butyl ethers, butyl esters, and styrenes. A compound (monomer) having one bond can be obtained.

[0082] Examples of the monomer include the following. Methyl acrylate, ethyl acrylate, propyl acrylate, amyl acrylate, cyclohexyl acrylate, ethyl hexyl acrylate, octyl acrylate, t-octyl acrylate, chlorethyl acrylate, 2-hydroxyethyl acrylate 2,2-dimethylhydroxypropyl acrylate, 5-hydroxypentyl acrylate, trimethylol propane monoacrylate, pentaerythritol monoacrylate, benzyl acrylate, methoxybenzyl acrylate, furfuryl acrylate, tetrahydrofluor Furyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropylenomethacrylate, aminoremethacrylate, hexyl methacrylate, cyclohexyl methacrylate Talylate, benzyl metatalylate, chlorbenzil metatalylate, octyl metatalylate, 2-hydroxybutynore metatalylate, 4-hydroxybutynole metatalylate, 5-hydroxypentyl metatalylate, 2, 2 Dimethyl monohydroxypropyl metatalylate, trimethylol propane monometatalylate, pentaerythritolol monometatalylate, furfurinore methacrylate, tetrahydrofurfuryl metatalylate,

 Compounds represented by the following formulas (VII-1) and (VII-2).

 [0083] [Chemical 25]

 (VII-1) (VII-2)

[0084] In the above formulas (VII-1) and (VII-2), Q represents any of the following groups (al) to (a6).

[0085] [Chemical 26] C—— R 63

 (a l)

 , 62

R ⁶⁴

-C—— O—— R ⁶⁵ (a2)

 H

In the above formula, R ″ to R ^{b &} are independently a carbon number such as methyl group, ethyl group, n-propyl group, isopropyl group, n butyl group, isobutyl group, sec butyl group, t butyl group, etc. Represents an alkyl group of 6; or an alicyclic hydrocarbon group.

R ⁶⁶ represents a hydrogen atom; or an alkyl group having 1 to 6 carbon atoms such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec butyl group, or a t-butyl group; .

Z represents an atomic group necessary for forming an alicyclic hydrocarbon group together with a carbon atom. R ⁶⁷ is an alkyl group having 1 to 6 carbon atoms such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec butyl group, or a t-butyl group; or an alicyclic carbonization Represents a hydrogen group.

Examples of the alicyclic hydrocarbon group of ¹ to R ^ea include an adamantyl group, a noradamantyl group, a decalin group, a tricyclodeoxy group, a tetracyclodecanyl group, a norbornyl group, a cedrol group, a cyclohexyl group, and a cyclooctyl group. Group, cyclodephenyl group, cyclododecanyl group and the like. Specific examples of the compounds represented by the formulas (VII-1) and (VII-2) are shown below.

[0088] [Chemical 27]

[0089] [Chemical 28]

[62 ^] [0600]

t7.M0 / S00Zdf / X3d 03 8t99I0 / 900Z OAV

[0091] [Chemical 30]

[TS ^] [2600]

t7.M0 / S00Zdf / X3d ζζ 8t99I0 / 900Z OAV

OL lO / SOOZd / lDd £ Z 8t99 orchid OOZ OAV [0094] [Chemical 33]

[0095] [Chemical 34]

Acrylamide, N-alkylacrylamide (alkyl group having 1 to 10 carbon atoms, for example, methyl group, ethyl group, propyl group, butyl group, t-butyl group, heptyl group, octyl group, cyclohexyl group, hydroxy group) , N, N-dialkyl acrylamide (the alkyl group having 1 to 10 carbon atoms, for example, methyl group, ethyl group, butyl group, isobutyl group, ethylhexyl group, cyclohexyl group) N-Hydroxychetyl-N-Methylacrylamide, N-2-Acetamidoethyl-N-Acetylacrylamide, Methacrylamide, N-Alkylmethacrylamide (the alkyl group has 1 to L carbon atoms) For example, methyl group, ethyl group, t-butyl group, ethylhexyl group, hydride Such as loxochetyl group, cyclohexyl group, etc.), N, N dialkylmethacrylamide (alkyl groups include ethyl group, propyl group, butyl group etc.), N hydroxyethyl —N-methylmethacrylamide, etc. (Meth) acrylamides;

[0097] Alkyl butyl ether (for example, hexyl vinyl ether, octyl vinyl ethere, decenorevinino reetenore, ethino hexeno vinino reetenole, methoxy ethino revino ethenore, ethoxy ethino levino reetenole, chrono Reethino Levinino Reethenole, 1 Methinole 2, 2-Dimethylpropyl Vinyl Ether, 2-Ethyl Butyl Vinyl Ether, Hydroxetyl Vinyl Ether, Diethylene Glycol Vinyl Ether, Dimethylamino Ethyl Butyl Ether, Jetyl Amino Ethyl Butyl Ether, Butino Reamino Butyl ethers such as chinole butyl ether, benzyl butyl ether, tetrahydrofurfuryl butyl ether;

 [0098] Bulle butyrate, Bulle isobutyrate, Bulle trimethylacetate, Bullecetyl noleacetate, Vininorevalate, Bilcaproate, Bullechloracetate, Bulle dichloracetate, Vinylmethoxyacetate, Vinylbutoxyacetate, Vinylacetate acetate, Bulratetate , Vinyl esters such as vinyl-β-phenylbutyrate and burcyclohexylcarboxylate;

 [0099] Itaconic acid esters such as dimethyl itaconate, decyl itaconate, dibutyl itaconate; dialkyl or monoalkyl esters of fumaric acid; dialkyl itaconates such as dibutyl fumarate;

 [0100] Other monomers such as crotonic acid, itaconic acid, maleic anhydride, maleimide, acrylonitrile, metathali-tolyl, malono-tolyl; and

 And styrenes represented by the following formulas (IX-1) to (IX-3).

 [0101] [Chemical 35]

(ΙΧ-2) (ΪΧ-3) [0102] formula (IX- 1) in ^{~ (IX- 3), R 71} , R 7 R 7b represents a hydrogen atom or a methylation group independently.

R ⁷² , R ⁷⁴ and R ⁷⁷ are each independently an alkyl group having 1 to 6 carbon atoms such as a methyl group, an ethyl group, an isopropyl group or a t-propyl group; or a halogen atom such as a fluorine atom or a chlorine atom; Represents.

r, s, t, and u each independently represent an integer of 0 to 2. When r, s, t, and u are each 2, R ⁷² , R ⁷⁴ , R ^77, and R ⁷⁸ are These may be the same or different.

[0103] In addition, R ⁷⁵ represents an acid-decomposable 'leaving group. Here, the acid-decomposable leaving group means a group that is decomposed and Z or eliminated by an acid. Specifically, methoxymethyl group, 2-methoxyethoxymethyl group, bis (2-cycloethoxy) methyl group, tetrahydrovinyl group, 4-methoxytetrahydrovinyl group, tetrahydrofuranyl group, triphenylmethyl Group, 2- (trimethylsilyl) ethoxymethyl group, trimethylsilyl group, t-butyldimethylsilyl group, trimethylsilylmethyl group, tbutyl group, t-butoxycarbonyl group, t-butoxycarbonylmethyl group, 2-methyl-2 — T-Butoxycarbo-ruethyl group can be exemplified.

Examples of R ⁷⁸ include groups represented by the following formula (X).

[0104] [Chemical 36]

[0105] In the above formula (X), R represents an unsubstituted or alkoxy-substituted alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 5 to 10 carbon atoms, or an unsubstituted or alkoxy group having 6 to 20 carbon atoms. Represents a substituted aryl group, R ⁸² represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and R ⁸³ represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or an alkoxy group having 1 to 6 carbon atoms. Represents.

[0106] Specific examples of the group represented by the formula (X) include 1-methoxyethyl group, 1-ethyloxy group, 1-methoxypropyl group, 1-methyl-1-methoxyethyl group, and 1- (isopropoxy) ethyl. Groups. [0107] In the above formulas (IX-1) to (IX-3), the substitution position of the hydroxyl group (OH group) and the group represented by the formula: OR ⁷⁵ is not particularly limited. The position or meta position is preferred.

 [0108] The arm portion of the star polymer of the present invention may be a homopolymer made of one of these monomers or a copolymer of two or more kinds, but is preferably a copolymer. . In addition, there are no particular restrictions on the type of copolymer, such as a random copolymer or a block copolymer.

 [0109] The ratio of each repeating unit in the arm portion of the star polymer of the present invention is determined by, for example, resist dry etching resistance, standard stock solution suitability, substrate adhesion, resist file, and general resist performance. It can be set as appropriate in consideration of certain resolution, heat resistance, sensitivity, and the like.

[0110] Specifically, the ratio of each repeating unit in the arm portion of the star polymer of the present invention can be arbitrarily selected by the ratio of the monomer used for the reaction, for example, a repeating unit having a rataton ring. The content of the unit is 30 to 70 mol%, preferably 35 to 65 mol%, more preferably 40 to 60 mol%, based on all the repeating units of the arm part. The content of the repetition unit having an alicyclic skeleton, in the arm portion all repeating units is usually 20 to 75 mol%, preferable properly 25 to 70 mole _^0/0, more preferably at 30 to 66 mole% is there. The content of the repeating unit having a Rataton rings and structure other than the alicyclic skeleton is usually total monomer in 0 to 70 mol%, preferably from 2 to 40 mol _^0/0, more preferably 5 to 30 mol ^_0/0.

 [0111] The number average molecular weight (Mn) of the arm part measured by gel 'permeation' chromatography is preferably 1,000 to 1,000,000, more preferably 1,500 to 500, in terms of polystyrene. , 000, more preferred <ί or 2,000-200, 000, specially preferred <ί or 2,500 to 100, 000.

 [0112] The ratio (MwZMn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) of the arm is in the range force S of 1.01 to 3.00, preferably in the range of 1.01 to 2.00 More preferred is S, and the range of 1.01 to L50 is more preferred.

[0113] As a method for producing the star polymer of the present invention, (a) in the presence of a cation polymerization initiator, (meth) acrylate or the like having an alicyclic skeleton, a rataton ring, or the like is polymerized. A method of synthesizing an arm polymer and then reacting a poly (meth) attaleito compound, (b) In the presence of a polymerization initiator, a poly (meth) atalyte toy compound is reacted to form a polyfunctional core, and then (meth) acrylate and the like having an alicyclic skeleton and a rataton ring are used. -On-polymerization method, (C) In the presence of an anion polymerization initiator, (meth) atallylate having an alicyclic skeleton and a rataton ring, etc. is ion-polymerized to synthesize an arm polymer, , A method of reacting a polyfunctional coupling agent, and further reacting a monomer capable of ion polymerization

, Etc. can be illustrated. Among these, the methods (a) and (c) are preferable for producing a star polymer with easy reaction control and a controlled structure.

 [0114] Examples of the key-on polymerization initiator used in the above-mentioned key-on polymerization include alkali metals and organic alkali metals. Examples of the alkali metal include lithium, sodium, potassium, cesium and the like, and examples of the organic alkali metal include the above-mentioned alkali metal alkylates, arylates and arylides. Specific examples include ethynolethium, n-butynolethium, sec-butynolethium, tertbutylenolithium, ethylsodium, lithium biphenyl, lithium naphthalene, lithium triphenyl, sodium naphthalene, α-methylstyrene. Examples include sodium dione, 1,1-diphenylhexyllithium, 1,1-diphenyl-3-methylpentyllithium, and the like.

 [0115] The polymerization reaction for synthesizing the arm polymer in the above method (a) or (c) includes a method of dropping a monomer polymerization initiator into a monomer (mixed) liquid, a monomer polymerization initiator, The method of dropping the monomer (mixed) solution into the solution containing can also be performed by a deviation method. Among these, since it is easy to control the molecular weight and the molecular weight distribution, a method of dropping a monomer (mixed) solution into a solution containing a polymerization initiator is preferred.

 [0116] The synthesis reaction of the arm polymer is usually carried out in an organic solvent under an inert gas atmosphere such as nitrogen gas or argon gas, in the range of −100 + 50 ° C, preferably −100 + 40 ° C. Done under temperature,

[0117] Examples of the organic solvent used in the synthesis reaction of the arm polymer include aliphatic hydrocarbons such as n-xane and n-heptane; alicyclic hydrocarbons such as cyclohexane and cyclopentane; benzene and toluene Aromatic hydrocarbons such as: ethers such as jetyl ether, tetrahydrofuran (THF), dioxane, and azole; amides such as hexamethylphosphoramide; The organic solvent used can be used. this These solvents can be used alone or in combination of two or more. Of these, from the viewpoint of polarity and solubility, it is preferable to use a mixed solvent of tetrahydrofuran and toluene, tetrahydrofuran and hexane, tetrahydrofuran and methylcyclohexanone! / ,.

 [0118] Examples of the polymerized form of the arm polymer include random copolymerization, partial block copolymerization, and complete block copolymerization. These can be synthesized by selecting the method of adding (meth) acrylates to be used.

 [0119] In the reaction to form a star polymer using the arm polymer thus obtained as a branched polymer chain, the above-mentioned poly (meth) alkyl relay toy compound is added to the reaction solution after the end of the arm polymer synthesis reaction. This can be done.

 [0120] This reaction is usually performed at 100 ° C to + 50 ° C, preferably 70 ° C to + 40 ° C in an organic solvent under an inert gas atmosphere such as nitrogen gas or argon gas. By conducting the polymerization reaction at a temperature, a polymer having a controlled structure and a narrow molecular weight distribution can be obtained.

 [0121] In addition, the star polymer formation reaction can be performed continuously in the solvent used to form the arm polymer, but the solvent composition is changed by adding a solvent, or the solvent is separated. It can also be carried out by substituting the solvent. As the powerful solvent, the same solvents as those used in the arm polymer synthesis reaction can be used.

 [0122] In the method for producing a star polymer of the present invention, an alicyclic skeleton and a poly (meth) acrylate compound (P) and a cation polymerization method using a cation polymerization initiator as a polymerization initiator are used. It is preferable that the molar ratio [(P) / (D)] of the active terminal (D) of the polymer chain obtained by polymerizing the (meth) atarylate having a bilatonic ring is 0.1 to 10! /, .

 [0123] The reaction between an arm polymer chain and a poly (meth) atari toy compound is a method of adding a poly (meth) atta relay toy compound to an arm polymer chain having an active end. Any method of adding an arm polymer chain having an active end to the rate compound can be employed.

[0124] The number of arms of the star polymer is determined by the addition amount of poly (meth) atalylate compound, the reaction temperature, and the reaction time, but usually the end of the living polymer and the poly (meth) atalytoy compound, etc. Multiple star block copolymers with different numbers of arms are produced at the same time due to the difference in reactivity with vinyl groups and steric hindrance. [0125] Further, the ratio (MwZMn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) of the star polymer to be produced is preferably in the range of 1.00 to L50 (weight average molecular weight ( Mw) ί or 3,000 powers, 300, 000 powers! / ヽ.

 [0126] For the central nucleus (polyfunctional core) having an active end formed by reacting a pre-adjusted arm polymer chain with a poly (meth) atreatoi compound, etc., a-on polymerization In the method (c) in which possible monomers are reacted to form a new arm polymer chain, a star polymer having different types of arm polymer chains can be produced.

 [0127] The active terminal present in the central core can be reacted with a directly polymerizable monomer, but after reacting with a compound such as diphenylethylene or stilbene, or with lithium chloride or the like. After adding an alkali metal or alkaline earth metal mineral salt, the monomer is reacted more highly, like an acrylic acid derivative, and when the monomer is reacted, the polymerization reaction proceeds slowly. And may be advantageous in controlling the overall structure of the polymer produced.

 [0128] The above reaction can also be carried out continuously in the solvent used to form the central nucleus having an active end, but the solvent composition is changed by adding a solvent, or the solvent is replaced with another solvent. It is also possible to replace it with. Examples of the powerful solvent include the same solvents as those used for the synthesis of the arm polymer.

 [0129] Further, two types of monomers are used as an arm polymer chain newly introduced to the active terminal existing in the central core in the method (c) or as an arm polymer chain in the method (b). By mixing and reacting, it is possible to make a polymer chain randomly copolymerized, or it can be made a block polymer chain by adding two kinds of monomers sequentially.

[0130] The star polymer of the present invention has a structure that can be easily cleaved by an acid, and can be suitably used for a resist material or the like. For example, the star polymer of the present invention is converted into a photoacid generator and, if necessary, an acid-decomposable dissolution inhibiting compound, a dye, a plasticizer, a surfactant, a photosensitizer, an organic basic compound, and a developer. An acid-decomposable rosin composition can be prepared by dissolving it in a suitable organic solvent together with a compound that promotes solubility in water. This composition is useful as a resist composition. [0131] The photoacid generator is not particularly limited as long as it is a compound that generates an acid upon irradiation with actinic rays or radiation. For example, known light (400-200 nm) used in photoinitiators for photopower thione polymerization, photoinitiators for photoradical polymerization, photodecolorants for dyes, photochromic agents, or microresists. Ultraviolet rays, deep ultraviolet rays, particularly preferably g-line, h-line, i-line, KrF excimer laser beam), ArF excimer laser beam, electron beam, X-ray, molecular beam or ion beam and compounds that generate acids Mixtures and the like can be used.

 [0132] The addition amount of these photoacid generators is generally used in the range of 0.001 to 30% by weight, preferably 0.3 to 20% by weight, more preferably based on the solid content in the composition. Is in the range of 0.5 to 10% by weight.

 [0133] The organic solvent used in the preparation of the acid-decomposable rosin composition includes ethylene dichloride, cyclohexanone, cyclopentanone, 2-heptanone, γ-butyrolatatane, methinoreethinoleketone, ethylene glycol monomono. Methinoleethenore, Ethylene Glycole Monomethinoleetenore

, 2-methoxyethyl acetate, ethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, toluene, ethyl acetate, methyl lactate, ethyl lactate, methyl methoxypropionate, ethyl ethoxypropionate, Examples include methyl pyruvate, ethyl pyruvate, propyl pyruvate, Ν, Ν-dimethylformamide, dimethyl sulfoxide, メ チ ル -methylpyrrolidone, and tetrahydrofuran.

[0134] The obtained acid-decomposable resin composition is applied onto a substrate by an appropriate application method such as a spinner or a coater, then exposed through a predetermined mask, subjected to beta, and using a developer. A good resist pattern can be obtained by imaging.

[0135] Here, the exposure light is preferably 150ηπ! Light with a wavelength of ~ 250nm. Specifically, KrF excimer laser (248nm), ArF excimer laser (193nm), F excimer

 2 Malaser (157 nm), X-ray, electron beam, etc.

[0136] Developers include inorganic hydroxides such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, and aqueous ammonia, and primary amines such as ethylamine and n-propylamine. , Secondary amines such as jetylamine, di-n-butylamine, Tertiary amines such as triethylamine, methyljetylamine, alcohol amines such as dimethylethanolamine, triethanolamine, quaternary ammonium salts such as tetramethylammonium hydroxide, tetraethylammonium hydroxide, Alkaline aqueous solutions such as cyclic amines such as pyrrole and pyrrolidine can be used. Furthermore, alcohols and surfactants can be added in appropriate amounts to the alkaline aqueous solution. Example

 [0137] Hereinafter, the present invention will be described in more detail using examples, but the present invention is not limited to the examples.

[Example 1]

 [Synthesis of acetal bond-containing dimetatalylate (acetal dimethacrylate) obtained by attaching 2-hydroxyethyl methacrylate to ethylene glycol dibutyl ether]

 Under a nitrogen atmosphere, stirring a mixture of 2-hydroxyethyl methacrylate 78.08 g (0.60 mol), p-toluenesulfonic acid monohydrate 0.60 g (3.18 mmol) and tetrahydrofuran (THF) 600 g, Ethylene glycol dibule ether (34.24 g, 0.30 mol) was added with water cooling (about 15 ° C), and the mixture was further stirred for 1 hour after completion of the dropwise addition (the reaction temperature rose to 31 ° C). A small amount of the reaction solution was taken out from the reaction mixture, and it was confirmed by gas chromatography (hereinafter abbreviated as “GCJ”) and thin layer chromatography (hereinafter abbreviated as “TLC”) that the raw materials were completely consumed.

[0139] An aqueous alkali solution prepared by dissolving 1.20 g (14.28 mmol) of sodium hydrogen carbonate in 200 ml of ion-exchanged water was added to the reaction solution and stirred for several minutes. The reaction mixture was extracted with jetyl ether, and the organic layer was separated. The organic layer was dried over anhydrous magnesium sulfate and the anhydrous magnesium sulfate was filtered off, and the obtained filtrate was concentrated by a rotary evaporator. The concentrate power obtained using a vacuum pump was completely removed under reduced pressure to give 118.89 g of colorless clear oil (Yield = 99%). — By measuring NMR ^ vector, it was confirmed that the obtained transparent oil contained almost 100% of the target product.

[0140] (Example 2) [Synthesis of acetal bond-containing dimetatalate obtained by attaching 2-hydroxyethyl methacrylate to 1,4 cyclohexane dimethanol dibute ether]

The target product (colorless transparent oil) was quantitatively obtained in the same manner as in Example 1, except that 1,4-cyclohexanedimethanol dibule ether was used in place of ethylene glycol dibule ether. It was. The structure of the crude product was determined by measuring ¹ H-NMR spectrum and confirmed to be of sufficient purity.

(Example 3)

 [Synthesis of acetal bond-containing dimethacrylate (acetal dimethacrylate) obtained by attaching 2-hydroxyethyl methacrylate to 1,6 hexanediol dibutyl ether]

The target product (colorless transparent oil) was quantitatively obtained in the same manner as in Example 1 except that 1,6 hexanediol dibule ether was used in place of ethylene glycol dibule ether. The structure of the crude product was determined by measuring ¹ H-NMR spectrum and confirmed to be of sufficient purity.

(Example 4)

 [Synthesis of acetal bond-containing dimetatalylate obtained by attaching 2-buoxetyl methacrylate to methacrylic acid: acetal dimetatalylate 4]

At room temperature (22 ° C, under water cooling), stir into a mixture of 78.09 g (0.50 mol) of bisuxetyl methacrylate, 45.20 g (0.53 mol) of methacrylic acid and 500 g of tetrahydrofuran (THF). Then, 2.85 g (15. Ommol) of p-toluenesulfonic acid monohydrate was added. The reaction was carried out under a nitrogen atmosphere, and the mixture was stirred for 1 hour while confirming that the moderate temperature rise had subsided (rise to 30 ° C). A small amount of the reaction solution was taken out from the reaction mixture, and it was confirmed by GC and TLC that the raw materials were completely consumed. An aqueous alkali solution prepared by dissolving 3.15 g (37.5 mmol) of sodium hydrogen carbonate in 200 mL of ion exchange water was added and stirred for a while to stop the reaction. The reaction mixture was subjected to extraction using jetyl ether, the mixed organic layer was separated, and the obtained mixed organic layer was sufficiently dried using anhydrous magnesium sulfate. After removing anhydrous magnesium sulfate by filtration, the filtrate is put on a rotary evaporator. The organic solvent was distilled off under reduced pressure. Further, the organic solvent was removed under reduced pressure using a vacuum pump to obtain a colorless transparent oil (about 120 g) almost quantitatively. This crude product was purified by alumina column chromatography to obtain 108.51 g of the desired product (yield 90%). The structure was determined by measuring the ¹ H-NMR ^ vector and was confirmed to be of sufficient purity.

[0142] (Example 5)

 [Star polymer with t-butyl methacrylate homopolymer as arm polymer and acetal dimetatalylate 1 as core (synthesis of star polymer jj)

 Under a nitrogen atmosphere, at 40 ° C, tetrahydrofuran (hereinafter abbreviated as THF) containing 0.17 g (4. OO mmol) of lithium chloride was added to 153.78 g while stirring with 1.0 M sec-butyllithium (hereinafter “SBL”). Abbreviated as “) Z cyclohexane · η-hexane solution 6.22 g (about 8.08 ml, 0.46 g converted to SBL, 8. OOmmol equivalent) was added.

 Next, 40.OOg of THF solution containing 20.00 g (0.14 mol) of t-butylmetatalylate (hereinafter abbreviated as “tBMA”) was added dropwise to this solution, and the reaction was continued for 30 minutes. A small amount of the reaction solution was taken out from the reaction mixture, and it was confirmed by GC that the monomer was completely consumed. Polymerization was continued for 1 hour from the end of the dropwise addition of tB MA, and sufficient aging was performed.

 [0144] Next, 23.96 g of a THF solution containing 11.98 g (32.OOmmol) of acetal dimetatalylate 1 was dropped, and a small amount of the reaction solution was taken out from the reaction mixture and stored every hour. After completion of the dropwise addition of dimetatalylate, polymerization was continued for 3 hours to sufficiently ripen the mixture, and a THF solution containing hydrochloric acid was added to the reaction solution to stop the reaction. The reaction mixture was poured into a large amount of methanol Z water to precipitate a polymer. The precipitated polymer was collected by filtration, washed and dried to obtain a white powdery polymer. The obtained polymer was redissolved in THF, and then poured into a large amount of methanol Z water to precipitate the polymer. After filtration, washing and drying under reduced pressure for 10 hours, a white powdered star polymer 1 was obtained.

 [0145] Analysis of the obtained star polymer 1 by gel permeation 'chromatography (hereinafter abbreviated as "GPC analysis") revealed that Mw = 19, 500, M w / Mn = l. 16, area = 82%, arm polymer part Mw = 4,800, Mw / Mn = 1.06, area = 18%.

[Example 6] [Synthesis of star polymer (star polymer) with t-butyl methacrylate homopolymer as arm polymer and acetal dimetatalylate 2 as core]

 Implementation f Row 4 [Koo! /, Acetanoresimethacrylate 1 11.98 g (32. OOmmol) [Instead of using 29.22 g (32. OOmmol) of Acetal dimetatalylate 2] In the same manner as in Example 4, a white powdery star polymer 2 was obtained.

 GPC analysis of star polymer 2 revealed that Mw = 36,200 in the star polymer part, Mw / Mn = l. 30, Area = 86%, Mw = 4, 100 in the arm polymer part, Mw / M n = l 08, area = 14%.

[Example 7]

 [Synthesis of star polymer (star polymer ^) with t-butyl methacrylate homopolymer as arm polymer and acetal dimetatalylate 4 as core]

 In the same manner as in Example 5, 7.75 g (32.OOmmol) of acetal dimetatalylate 3 was used to obtain a white powdery star polymer. GPC analysis of the obtained polymer revealed that Mw = 22500 in the star polymer portion, Mw / Mn = l. 20, area = 66%, Mw = 3200 in the arm polymer portion, Mw / Mn = l. 08, Area = 23%, other by-product polymer portion (corresponding to coupling peak), Mw = 6400, Mw / Mn = l.03, area = 11%.

 [0148] Acid Degradability Test and Thermal Stability Test (1)

 The acid decomposability and thermal stability of star polymers containing acetal bonds in the core portion were tested according to the following procedure. That is, for a 5.0 wt% THF solution of star polymer 1, a sample containing 2 parts of camphorsulfonic acid (hereinafter abbreviated as “CS”) and a sample not containing CS are prepared for the polymer, This was done by analyzing the GPC chart of the sample after heating at 130 ° C for 5 minutes.

 [0149] Star polymer 1 is decomposed into an arm polymer in the stage before heating due to the presence of CS, and is well decomposed into an arm polymer after 5 minutes of heating, including high molecular weight polymer partially generated by acid. It was confirmed.

[0150] These acid-decomposable properties are comparable to star polymers using tertiary alcohol type cores such as 2,5 dimethyl-2,5-hexanediol dimetatalylate (MDMA) under the same conditions. It is very good. On the other hand, in the absence of CS, it was confirmed that the star polymer 1 was not affected until 5 minutes after heating.

 From the viewpoint of the properties required for resist materials, for example, the above behavior is stable during heating operations (baking, etc.), and rapidly decomposes the core due to acid generation during exposure (degradation of molecular weight). When it happens, it is said that it is an excellent characteristic.

Acid degradation test and thermal stability test (2)

 The same acid decomposability and thermal stability tests were conducted on the star polymer 2 in accordance with the same operations as in the acid decomposability test and thermal stability test (1).

 It was confirmed that Star Polymer 2 also shows exactly the same tendency as Star Polymer 1.

Claims

The scope of the claims

 [1] Formula (I)

 [Chemical 1]

(Wherein R ¹ and R ² each independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, A represents a divalent or higher valent organic linking group not containing an acetal structure, and B represents an acetal. Represents a divalent or higher-valent organic linking group having a structure or an organic linking group that forms an acetal structure together with an ester oxygen atom, and nl to! Ι4 each independently represents an integer of 1 or more, When nl is 2 or more, R ¹ may be the same or different. When n2 is 2 or more, R ¹ and A may be the same or different. When n3 is 2 or more R ² may be the same or different from each other. When n4 is 2 or more, R ² and B may be the same or different from each other. A star polymer having a core part.

 [2] The star polymer according to claim 1, wherein in the formula (I), A is a hydrocarbon group having 2 or more carbon atoms and 2 or more valences.

 [3] The star polymer according to claim 1 or 2, wherein in the formula (I), A is an alkylene group having 2 or more carbon atoms.

 [4] In the formula (I), B represents the formula (II)

[Chemical 2]

(Wherein R ¹¹ and R ¹² each independently represents a hydrogen atom or an organic group, and Α ¹ represents a divalent or higher valent organic linking group), or a group represented by the formula (II The functional group represented by (1) is a functional group having a partial structure in a partial structure. Terpolymer.

 [5] In the formula (I), B represents the formula (III)

 [Chemical 3]

-

(Wherein, R ″ to R ¹⁴ each independently represents a hydrogen atom or an organic group, A ¹ and ΑΊ each independently represent a divalent or higher valent organic linking group, and ml represents 1 or more. When ml is 2 or more, R ^{13 s} , R ^{14 s,} and A ^{2 s} may be the same or different.) Or a group represented by the formula (III) The star polymer according to any one of claims 1 to 3, wherein the star polymer is a functional group having a functional group in a partial structure.

[6] The star polymer according to [5], wherein in the formula (ΠΙ), A ¹ and A ² are each independently a divalent or higher valent hydrocarbon group.

[7] In the formula (III), A ¹ and A ² are each independently a chain alkylene group, a cycloalkyl alkylene group, or placing serial to claim 5 or 6, wherein the cycloalkyl alkylene group Star polymer.

 [8] The compound represented by the formula (I) is represented by the formula (IV):

 [Chemical 4]

(In the formula, R ¹ and R ² each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms; R ^{21 to} R ²⁴ each independently represents a hydrogen atom or an organic group; ^11, a ¹² and a ^{1 3} is star polymer according to claim 1, feature to be the compound represented by each independently represent a divalent organic linking group.).

[9] The star polymer according to [8], wherein in the formula (IV), A ¹¹ and A ¹³ are each independently a divalent organic linking group having 2 or more carbon atoms. [10] In the formula (IV), A ¹¹ and A ^ld are star polymer according to claim 8, characterized in that each independently divalent hydrocarbon group having 2 or more carbon atoms.

[11] In the formula (IV), A ¹¹ and A ¹³ are the star polymer according to claim 8, characterized in that each independently an alkylene group having 2 or more carbon atoms.

[12] In the formula (IV), A ¹² is, according to claim 8-11, which is a divalent hydrocarbon radical

V, a star polymer as described in somewhere.

[13] In the formula (IV), A ¹² is a chain alkylene group, as claimed in any of claims 8-12, characterized in that a cycloalkylene group, or a cycloalkyl Ruarukiren group Sutapori

[14] The star polymer according to any one of [1] to [13], wherein the formula (I) does not include a partial structure in which an ester oxygen atom is a part of an acetal structure.

 [15] An acid-decomposable rosin composition comprising the star polymer according to any one of claims 1 to 14.

 16. The acid-decomposable rosin composition according to claim 15, further comprising a compound that generates an acid in response to an external stimulus.

[17] A resist composition comprising the star polymer according to any one of [1] to [14] and a compound capable of generating an acid in response to an external stimulus.

[18] Formula (V)

 [Chemical 5]

(Wherein R ¹ and R ² each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, R ^{31 to} R ³⁴ each independently represents a hydrogen atom or an organic group, and A ²¹ , A ^{23 each} independently represents a divalent organic linking group, and A ²² represents a divalent organic linking group having an alicyclic skeleton.) Compound.

In formula (V), A ²¹ and A ²³ are each independently a divalent organic linkage having 2 or more carbon atoms. 19. The di (meth) atareto toy compound according to claim 18, which is a base.

[20] In the formula (V), A ²¹ and A ²³ are each independently di- according to claim 18 which is a divalent hydrocarbon group having 2 or more carbon atoms (meth) Atari Ratei compound.

[21] In the formula (V), A ²¹ and A ²³ are each independently di (meth) Atari rate b匕合of claim 18, characterized in that an alkylene group having 2 or more carbon atoms object.

[22] In the formula (V), A ²² is a cycloalkylene group or a di (meth) Atari rate b匕合product according to any one of claims 18-21, wherein the cycloalkyl alkylene group .