RESIN, RESIST COMPOSITION AND METHOD FOR PRODUCING RESIST PATTERN, AND COMPOUND

Abstract

Disclosed are a resin comprising a structural unit represented by formula (I), and a structural unit represented by formula (a1-1) and/or a structural unit represented by formula (a1-2), and a resist composition including this resin:

##STR00001##

Claims

1. A resin comprising a structural unit represented by formula (I), and at least one structural unit selected from the group consisting of a structural unit represented by formula (a1-1) and a structural unit represented by formula (a1-2): ##STR00297## wherein, in formula (I), R.sup.1 represents a hydrogen atom or a methyl group, X.sup.1 represents a single bond or —CO—O—* (* represents a bonding site to Ar.sup.1), X.sup.2 represents —CO—O—*, —O—*, —O—CO—*, —O—CO— (CH.sub.2) or —O—(CH.sub.2).sub.nn—CO—O—* (* represents a bonding site to Ar.sup.2), mm and nn represent 0 or 1, Ar.sup.1 and Ar.sup.2 each independently represent an aromatic hydrocarbon group having 6 to 36 carbon atoms which may have a substituent, R.sup.2 each independently represent a hydrogen atom or an acid-labile group, or when two or more R.sup.2 exist, two R.sup.2 may combine together to form a group having an acetal ring structure, n represents an integer of 1 to 3, and when n is an integer of 2 or more, a plurality of R.sup.2 may be the same or different from each other: ##STR00298## wherein, in formula (a1-1) and formula (a1-2), L.sup.a1 and L.sup.a2 each independently represent —O— or *—O—(CH.sub.2).sub.k1—CO—O—, k1 represents an integer of 1 to 7, and * represents a bonding site to —CO—, R.sup.a4 and R.sup.a5 each independently represent a hydrogen atom or a methyl group, R.sup.a6 and R.sup.a7 each independently represent an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms, an alicyclic hydrocarbon group having 3 to 18 carbon atoms, an aromatic hydrocarbon group having 6 to 18 carbon atoms, or a group obtained by combining these groups, m1 represents an integer of 0 to 14, n1 represents an integer of 0 to 10, and n1′ represents an integer of 0 to 3.

2. The resin according to claim 1, wherein X.sup.1 is a single bond.

3. The resin according to claim 1, wherein X.sup.2 is —CO—O—* or —O—* (* represents a bonding site to Ar.sup.2).

4. The resin according to claim 1, wherein n is 1 or 2.

5. The resin according to claim 1, wherein the acid-labile group in R.sup.2 is a group represented by formula (1a) or a group represented by formula (2a): ##STR00299## wherein, in formula (1a), R.sup.aa1, R.sup.aa2 and R.sup.aa3 each independently represent an alkyl group having 1 to 8 carbon atoms which may have a substituent, an alkenyl group having 2 to 8 carbon atoms which may have a substituent, an alicyclic hydrocarbon group having 3 to 20 carbon atoms which may have a substituent, or an aromatic hydrocarbon group having 6 to 18 carbon atoms which may have a substituent, or R.sup.aa1 and R.sup.aa2 may be bonded each other to form an alicyclic hydrocarbon group having 3 to 20 carbon atoms together with carbon atoms to which R.sup.aa1 and R.sup.aa2 are bonded, naa represents 0 or 1, and * represents a bond: ##STR00300## wherein, in formula (2a), R.sup.aa1′ and R.sup.aa2′ each independently represent a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, R.sup.aa3′ represents a hydrocarbon group having 1 to 20 carbon atoms, or R.sup.aa2′ and R.sup.aa3′ may be bonded each other to form a heterocyclic group having 3 to 20 carbon atoms together with —C—X.sup.a— to which R.sup.aa2′ and R.sup.aa3′ are bonded, —CH.sub.2— included in the hydrocarbon group and the heterocyclic group may be replaced by —O— or —S—, X.sup.a represents an oxygen atom or a sulfur atom, and * represents a bond.

6. The resin according to claim 1, wherein R.sup.2 is a hydrogen atom, or n is 2 or more and two R.sup.2 combine together to form a group having an acetal ring structure.

7. The resin according to claim 1, further comprising a structural unit represented by formula (a2-A): ##STR00301## wherein, in formula (a2-A), R.sup.a50 represents a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms which may have a halogen atom, R.sup.a51 represents a halogen atom, a hydroxy group, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkoxyalkyl group having 2 to 12 carbon atoms, an alkoxyalkoxy group having 2 to 12 carbon atoms, an alkylcarbonyl group having 2 to 4 carbon atoms, an alkylcarbonyloxy group having 2 to 4 carbon atoms, an acryloyloxy group or a methacryloyloxy group, A.sup.a50 represents a single bond or * —X.sup.a51-(A.sup.a52-X.sup.a52).sub.nb—, and * represents a bonding site to carbon atoms to which —R.sup.a50 is bonded, A.sup.a52 represents an alkanediyl group having 1 to 6 carbon atoms, X.sup.a51 and X.sup.a52 each independently represent —O—, —CO—O— or —O—CO—, nb represents 0 or 1, and mb represents an integer of 0 to 4, and when mb is an integer of 2 or more, a plurality of R.sup.a51 may be the same or different from each other.

8. A resist composition comprising the resin according to claim 1 and an acid generator.

9. The resist composition according to claim 8, wherein the acid generator comprises a salt represented by formula (B1): ##STR00302## wherein, in formula (B1), Q.sup.b1 and Q.sup.b2 each independently represent a fluorine atom or a perfluoroalkyl group having 1 to 6 carbon atoms, L.sup.b1 represents a divalent saturated hydrocarbon group having 1 to 24 carbon atoms, —CH.sub.2— included in the divalent saturated hydrocarbon group may be replaced by —O— or —CO—, and a hydrogen atom included in the divalent saturated hydrocarbon group may be substituted with a fluorine atom or a hydroxy group, Y represents a methyl group which may have a substituent or an alicyclic hydrocarbon group having 3 to 24 carbon atoms which may have a substituent, and —CH.sub.2— included in the alicyclic hydrocarbon group may be replaced by —O—, —S(O).sub.2— or —CO—, and Z.sup.+ represents an organic cation.

10. The resist composition according to claim 8, further comprising a salt generating an acid having an acidity lower than that of an acid generated from the acid generator.

11. A method for producing a resist pattern, which comprises: (1) a step of applying the resist composition according to claim 8 on a substrate, (2) a step of drying the applied composition to form a composition layer, (3) a step of exposing the composition layer, (4) a step of heating the exposed composition layer, and (5) a step of developing the heated composition layer.

12. A compound represented by formula (IA): ##STR00303## wherein, in formula (IA), R.sup.1 represents a hydrogen atom or a methyl group, X.sup.1 represents a single bond or —CO—O—* (* represents a bonding site to Ar.sup.1), X.sup.2 represents —CO—O—*, —O—*, —O—CO—*, —O—CO—(CH.sub.2) or —O—(CH.sub.2).sub.nn—CO—O—* (* represents a bonding site to the benzene ring), mm and nn represent 0 or 1, Ar.sup.1 represents an aromatic hydrocarbon group having 6 to 36 carbon atoms which may have a substituent, R.sup.3 and R.sup.4 each independently represent a hydrogen atom or an acid-labile group, or R.sup.3 and R.sup.4 may combine together to form a group having an acetal ring structure, R.sup.5 represents a halogen atom, an alkyl fluoride group having 1 to 6 carbon atoms or an alkyl group having 1 to 12 carbon atoms, and —CH.sub.2— included in the alkyl group and the alkyl fluoride group may be replaced by —O— or —CO—, and n′ represents an integer of 0 to 3, and when n′ is 2 or more, a plurality of R.sup.5 may be the same or different from each other.

13. The compound according to claim 12, wherein X.sup.1 is a single bond.

14. The compound according to claim 12, wherein X.sup.2 is —CO—O—* or —O—* (* represents a bonding site to the benzene ring).

15. The compound according to claim 12, wherein n′ is 0.

16. The compound according to claim 12, wherein R.sup.3 and R.sup.4 are a hydrogen atom, or R.sup.3 and R.sup.4 combine together to form a group having an acetal ring structure.

17. A resin comprising a structural unit derived from the compound according to claim 12.

Description

EXAMPLES

[0767] The present invention will be described more specifically by way of Examples. Percentages and parts expressing the contents or amounts used in the Examples are by mass unless otherwise specified.

[0768] The weight-average molecular weight is a value determined by gel permeation chromatography. Analysis conditions of gel permeation chromatography are as follows.

[0769] Column: TSKgel Multipore HXL-M x 3+guardcolumn (manufactured by TOSOH CORPORATION)

[0770] Eluent: tetrahydrofuran

[0771] Flow rate: 1.0 mL/min

[0772] Detector: RI detector

[0773] Column temperature: 40° C.

[0774] Injection amount: 100 μl

[0775] Molecular weight standards: polystyrene standard (manufactured by TOSOH CORPORATION)

[0776] Structures of compounds were confirmed by measuring a molecular ion peak using mass spectrometry (Liquid Chromatography: Model 1100, manufactured by Agilent Technologies, Inc., Mass Spectrometry: Model LC/MSD, manufactured by Agilent Technologies, Inc.). The value of this molecular ion peak in the following Examples is indicated by “MASS”.

Synthesis Example 1: Synthesis of Compound Represented by Formula (I-17)

[0777] ##STR00252##

[0778] Parts of a compound represented by formula (I-17-a), 2.28 parts of a compound represented by formula (I-17-c), 100 parts of ethyl acetate and 15 parts of tetrahydrofuran were mixed, followed by stirring at 23° C. for 30 minutes. To the mixed solution thus obtained, 6.55 parts of a compound represented by formula (I-17-b) was added, followed by stirring at 23° C. for 18 hours. To the reaction mass thus obtained, 20 parts of n-heptane and 70 parts of ion-exchanged water were added and, after stirring at 23° C. for 30 minutes, the organic layer was isolated through separation. To the organic layer thus recovered, 60 parts of ion-exchanged water was added and, after stirring at 23° C. for 30 minutes, the organic layer was isolated through separation. This water washing operation was repeated four times. The organic layer thus obtained was concentrated and then the concentrated mass was isolated from a column (silica gel 60 N (spherical, neutral) 100-210 μm; manufactured by Kanto Chemical Co., Inc., developing solvent: n-heptane/ethyl acetate=1/1) to obtain 7.48 parts of a compound represented by formula (I-17-d).

##STR00253##

[0779] 5.90 Parts of a compound represented by formula (I-17-e), 7.10 parts of a compound represented by formula (I-17-f) and 30 parts of acetonitrile were mixed, followed by stirring at 23° C. for 30 minutes and further stirring at 60° C. for 1 hour. To the mixture thus obtained, 7.26 parts of a compound represented by formula (I-17-d) was added, followed by stirring at 60° C. for 1 hour. The reaction mass thus obtained was cooled to 23° C., and then 100 parts of ethyl acetate and 50 parts of ion-exchanged water were added and, after stirring at 23° C. for 30 minutes, the organic layer was isolated through separation. This water washing operation was repeated four times. The organic layer thus obtained was concentrated, and then the concentrated mass was isolated from a column (silica gel 60 N (spherical, neutral) 100-210 μm; manufactured by Kanto Chemical Co., Inc., developing solvent: n-heptane/ethyl acetate=5/1) to obtain 9.44 parts of a compound represented by formula (I-17).

[0780] MASS (mass analysis): 313.1 [M+H].sup.+

Synthesis Example 2: Synthesis of Compound Represented by Formula (I-25)

[0781] ##STR00254##

[0782] 5.00 parts of a compound represented by formula (I-25-a), 10.39 parts of a compound represented by formula (I-17-d), 50 parts of dimethylformamide and 11.14 parts of potassium carbonate were mixed, followed by stirring at 23° C. for 30 minutes and further stirring at 120° C. for 18 hours. The mixture thus obtained was cooled to 23° C., and then 150 parts of ion-exchanged water and 150 parts of ethyl acetate were added and, after stirring at 23° C. for 30 minutes, the organic layer was isolated through separation. To the organic layer thus obtained, 150 parts of ion-exchanged water was added and, after stirring at 23° C. for 30 minutes, the organic layer was isolated through separation. This water washing operation was repeated three times. The organic layer thus obtained was concentrated, and then the concentrated mass was isolated from a column (silica gel 60 N (spherical, neutral) 100-210 μm; manufactured by Kanto Chemical Co., Inc., developing solvent: n-heptane/ethyl acetate=5/1) to obtain 10.61 parts of a compound represented by formula (I-25-b).

##STR00255##

[0783] 17.16 Parts of a compound represented by formula (I-25-c), 5.39 parts of a compound represented by formula (I-25-d) and 120 parts of tetrahydrofuran were mixed, followed by stirring at 23° C. for 30 minutes and further cooling to 5° C. To the mixture thus obtained, 10.58 parts of a compound represented by formula (I-25-b) was added at 5° C. over 30 minutes, followed by temperature rising to 23° C., stirring at 23° C. for 12 hours and further filtration. To the filtrate thus obtained, 100 parts of ion-exchanged water and 200 parts of ethyl acetate were added and, after stirring at 23° C. for 30 minutes, the organic layer was isolated through separation. To the organic layer thus obtained, 100 parts of ion-exchanged water was added and, after stirring at 23° C. for 30 minutes, the organic layer was isolated through separation. This water washing operation was repeated three times. The organic layer thus obtained was concentrated, and then the concentrated mass was isolated from a column (silica gel 60 N (spherical, neutral) 100-210 μm; manufactured by Kanto Chemical Co., Inc., developing solvent: n-heptane/ethyl acetate=5/1) to obtain 6.82 parts of a compound represented by formula (I-25).

[0784] MASS (mass analysis): 285.1 [M+H].sup.+

Example 1: Synthesis of Compound Represented by Formula (I-43)

[0785] ##STR00256##

[0786] 5.00 Parts of a compound represented by formula (I-43-a), 0.008 part of a compound represented by formula (I-17-c) and 50 parts of toluene were mixed, followed by stirring at 23° C. for 30 minutes and further temperature rising to 100° C. To the mixed solution thus obtained, 6.19 parts of a compound represented by formula (I-43-b) was added dropwise at 100° C., followed by stirring at 110° C. for 2 hours and further cooling to 23° C. To the mixture thus obtained, 25 parts of ethyl acetate and 30 parts of ion-exchanged water were added and, after stirring at 23° C. for 30 minutes, the organic layer was isolated through separation. To the organic layer thus recovered, 30 parts of ion-exchanged water was added and, after stirring at 23° C. for 30 minutes, the organic layer was isolated through separation. This water washing operation was repeated three times. The organic layer thus obtained was concentrated to obtain 5.85 parts of a compound represented by formula (I-43-d).

##STR00257##

[0787] 4.20 Parts of a compound represented by formula (I-17-e), 5.06 parts of a compound represented by formula (I-17-f) and 30 parts of acetonitrile were mixed, followed by stirring at 23° C. for 30 minutes and further stirring at 60° C. for 1 hour. To the mixture thus obtained, 5.79 parts of a compound represented by formula (I-43-d) was added, followed by stirring at 60° C. for 1 hour. The reaction mass thus obtained was cooled to 23° C., and then 100 parts of ethyl acetate and 50 parts of ion-exchanged water were added and, after stirring at 23° C. for 30 minutes, the organic layer was isolated through separation. To the organic layer thus recovered, 50 parts of ion-exchanged water was added and, after stirring at 23° C. for 30 minutes, the organic layer was isolated through separation. This water washing operation was repeated three times. The organic layer thus obtained was concentrated, and then the concentrated mass was isolated from a column (silica gel 60 N (spherical, neutral) 100-210 μm; manufactured by Kanto Chemical Co., Inc., developing solvent: n-heptane/ethyl acetate=10/1) to obtain 3.10 parts of a compound represented by formula (I-43).

[0788] MASS (mass analysis): 297.1 [M+H].sup.+

Example 2: Synthesis of Compound Represented by Formula (I-33)

[0789] ##STR00258##

[0790] 2.95 Parts of a compound represented by formula (I-43), 1.89 parts of p-toluenesulfonic acid and 30 parts of acetonitrile were mixed, followed by stirring at 23° C. for 30 minutes and further stirring at 60° C. for 10 hours. The mixture thus obtained was cooled to 23° C., and then 50 parts of ethyl acetate and 20 parts of ion-exchanged water were added and, after stirring at 23° C. for 30 minutes, the organic layer was isolated through separation. To the organic layer thus obtained, 20 parts of ion-exchanged water was added and, after stirring at 23° C. for 30 minutes, the organic layer was isolated through separation. This water washing operation was repeated three times. The organic layer thus obtained was concentrated to obtain 1.95 parts of a compound represented by formula (I-33).

[0791] MASS (mass analysis): 257.1 [M+H].sup.+

Synthesis Example 3: Synthesis of Compound Represented by Formula (I-67)

[0792] ##STR00259##

[0793] Parts of a compound represented by formula (I-67-a), 2.28 parts of a compound represented by formula (I-17-c), 100 parts of ethyl acetate and 14 parts of tetrahydrofuran were mixed, followed by stirring at 23° C. for 30 minutes and further cooling to 10° C. To the mixed solution thus obtained, 6.55 parts of a compound represented by formula (I-17-b) was added dropwise at 10° C., followed by temperature rising to 23° C. and further stirring at 23° C. for 2 hours. To the mixture thus obtained, 70 parts of ion-exchanged water was added and, after stirring at 23° C. for 30 minutes, the organic layer was isolated through separation. This water washing operation was repeated five times. The organic layer thus obtained was concentrated, and then the concentrated mass was isolated from a column (silica gel 60 N (spherical, neutral) 100-210 μm; manufactured by Kanto Chemical Co., Inc., developing solvent: n-heptane/ethyl acetate=10/1) to obtain 8.75 parts of a compound represented by formula (I-67-d).

##STR00260##

[0794] 6.40 Parts of a compound represented by formula (I-17-e), 7.70 parts of a compound represented by formula (I-17-f) and 32 parts of acetonitrile were mixed, followed by stirring at 23° C. for 30 minutes and further stirring at 60° C. for 1 hour. To the mixture thus obtained, 8.65 parts of a compound represented by formula (I-67-d) was added, followed by stirring at 60° C. for 1 hour. The reaction mass thus obtained was cooled to 23° C., and then 100 parts of ethyl acetate and 50 parts of ion-exchanged water were added and, after stirring at 23° C. for 30 minutes, the organic layer was isolated through separation. This water washing operation was repeated four times. The organic layer thus obtained was concentrated, and then the concentrated mass was isolated from a column (silica gel 60 N (spherical, neutral) 100-210 μm; manufactured by Kanto Chemical Co., Inc., developing solvent: n-heptane/ethyl acetate=5/1) to obtain 9.84 parts of a compound represented by formula (I-67).

[0795] MASS (mass analysis): 313.1 [M+H].sup.+

Synthesis Example 4: Synthesis of Compound Represented by Formula (I-68)

[0796] ##STR00261##

[0797] 5.00 Parts of a compound represented by formula (I-67), 20 parts of IN hydrochloric acid and 30 parts of acetonitrile were mixed, followed by stirring at 23° C. for 10 hours. To the mixture thus obtained, 50 parts of ethyl acetate was added and, after stirring at 23° C. for 30 minutes, the organic layer was isolated through separation. To the organic layer thus obtained, 20 parts of ion-exchanged water was added and, after stirring at 23° C. for 30 minutes, the organic layer was isolated through separation. This water washing operation was repeated three times. The organic layer thus obtained was concentrated and then 100 parts of n-heptane was added, followed by stirring at 23° C. for 30 minutes and further filtration to obtain 3.75 parts of a compound represented by formula (I-68).

[0798] MASS (mass analysis): 241.1 [M+H].sup.+

Example 3: Synthesis of Compound Represented by Formula (I-49)

[0799] ##STR00262##

[0800] 2.50 Parts of a compound represented by formula (I-25-a), 4.74 parts of a compound represented by formula (I-43-d), parts of dimethylformamide and 5.57 parts of potassium carbonate were mixed, followed by stirring at 23° C. for 30 minutes and further stirring at 120° C. for 18 hours. The mixture thus obtained was cooled to 23° C., and then 80 parts of ion-exchanged water and 80 parts of ethyl acetate were added and, after stirring at 23° C. for 30 minutes, the organic layer was isolated through separation. To the organic layer thus obtained, 80 parts of ion-exchanged water was added and, after stirring at 23° C. for 30 minutes, the organic layer was isolated through separation. This water washing operation was repeated three times. The organic layer thus obtained was concentrated, and then the concentrated mass was isolated from a column (silica gel 60 N (spherical, neutral) 100-210 μm; manufactured by Kanto Chemical Co., Inc., developing solvent: n-heptane/ethyl acetate=5/1) to obtain 5.01 parts of a compound represented by formula (I-49-b).

##STR00263##

[0801] 8.58 Parts of a compound represented by formula (I-25-c), 2.70 parts of a compound represented by formula (I-25-d) and 60 parts of tetrahydrofuran were mixed, followed by stirring at 23° C. for 30 minutes and further cooling to 5° C. To the mixture thus obtained, 5.00 parts of a compound represented by formula (I-49-b) was added at 5° C. over 30 minutes, followed by temperature rising to 23° C., stirring at 23° C. for 12 hours and further filtration. To the filtrate thus obtained, 100 parts of ion-exchanged water and 200 parts of ethyl acetate were added and, after stirring at 23° C. for 30 minutes, the organic layer was isolated through separation. To the organic layer thus obtained, 100 parts of ion-exchanged water was added and, after stirring at 23° C. for 30 minutes, the organic layer was isolated through separation. This water washing operation was repeated three times. The organic layer thus obtained was concentrated, and then the concentrated mass was isolated from a column (silica gel 60 N (spherical, neutral) 100-210 μm; manufactured by Kanto Chemical Co., Inc., developing solvent: n-heptane/ethyl acetate=5/1) to obtain 3.22 parts of a compound represented by formula (I-49).

[0802] MASS (mass analysis): 269.1 [M+H].sup.+

Example 4: Synthesis of Compound Represented by Formula (I-37)

[0803] ##STR00264##

[0804] 2.67 Parts of a compound represented by formula (I-49), 1.89 parts of p-toluenesulfonic acid and 30 parts of acetonitrile were mixed, followed by stirring at 23° C. for 30 minutes and further stirring at 60° C. for 10 hours. The mixture thus obtained was cooled to 23° C., and then 50 parts of ethyl acetate and 20 parts of ion-exchanged water were added and, after stirring at 23° C. for 30 minutes, the organic layer was isolated through separation. To the organic layer thus obtained, 20 parts of ion-exchanged water were added and, after stirring at 23° C. for 30 minutes, the organic layer was isolated through separation. This water washing operation was repeated three times. The organic layer thus obtained was concentrated to obtain 1.69 parts of a compound represented by formula (I-37).

[0805] MASS (mass analysis): 229.1 [M+H].sup.+

Example 5: Synthesis of Compound Represented by Formula (I-81)

[0806] ##STR00265##

[0807] 5.00 parts of a compound represented by formula (I-81-a), 0.008 part of a compound represented by formula (I-17-c) and 50 parts of toluene were mixed, followed by stirring at 23° C. for 30 minutes and further temperature rising to 100° C. To the mixed solution thus obtained, 7.05 parts of a compound represented by formula (I-81-b) was added at 100° C., followed by stirring at 110° C. for 2 hours and further cooling to 23° C. To the mixture thus obtained, 25 parts of ethyl acetate and parts of ion-exchanged water were added and, after stirring at 23° C. for 30 minutes, the organic layer was isolated through separation. To the organic layer thus recovered, 30 parts of ion-exchanged water were added and, after stirring at 23° C. for 30 minutes, the organic layer was isolated through separation. This water washing operation was repeated three times. The organic layer thus obtained was concentrated, and then the concentrated mass was isolated from a column (silica gel 60 N (spherical, neutral) 100-210 μm; manufactured by Kanto Chemical Co., Inc., developing solvent: n-heptane/ethyl acetate=10/1) to obtain 2.19 parts of a compound represented by formula (I-81-d).

##STR00266##

[0808] 1.40 parts of a compound represented by formula (I-17-e), 1.69 parts of a compound represented by formula (I-17-f) and 20 parts of acetonitrile were mixed, followed by stirring at 23° C. for 30 minutes and further stirring at 60° C. for 1 hour. To the mixture thus obtained, 2.12 parts of a compound represented by formula (I-81-d) was added, followed by stirring at 60° C. for 1 hour. The reaction mass thus obtained was cooled to 23° C., and then 50 parts of ethyl acetate and 25 parts of ion-exchanged water were added and, after stirring at 23° C. for 30 minutes, the organic layer was isolated through separation. To the organic layer thus recovered, 25 parts of ion-exchanged water was added and, after stirring at 23° C. for 30 minutes, the organic layer was isolated through separation. This water washing operation was repeated three times. The organic layer thus obtained was concentrated, and then the concentrated mass was isolated from a column (silica gel 60 N (spherical, neutral) 100-210 μm; manufactured by Kanto Chemical Co., Inc., developing solvent: n-heptane/ethyl acetate=10/1) to obtain 1.03 parts of a compound represented by formula (I-81).

[0809] MASS (mass analysis): 313.1 [M+H].sup.+

Example 6: Synthesis of Compound Represented by Formula (I-71)

[0810] ##STR00267##

[0811] 1.03 Parts of a compound represented by formula (I-81), 0.63 part of p-toluenesulfonic acid and 10 parts of acetonitrile were mixed, followed by stirring at 23° C. for 30 minutes and further stirring at 60° C. for 10 hours. The mixture thus obtained was cooled to 23° C., and then 30 parts of ethyl acetate and 15 parts of ion-exchanged water were added and, after stirring at 23° C. for 30 minutes, the organic layer was isolated through separation. To the organic layer thus obtained, 15 parts of ion-exchanged water was added and, after stirring at 23° C. for 30 minutes, the organic layer was isolated through separation. This water washing operation was repeated three times. The organic layer thus obtained was concentrated to obtain 0.38 part of a compound represented by formula (I-71).

[0812] MASS (mass analysis): 257.1 [M+H].sup.+

Synthesis of Resin

[0813] Compounds (monomers) used in the synthesis of resins are shown below.

##STR00268## ##STR00269## ##STR00270## ##STR00271##

[0814] Hereinafter, these monomers are referred to as “monomer (a1-1-3)” according to the number of formula.

Example 7 [Synthesis of Resin A1]

[0815] Using a monomer (a1-4-2), a monomer (a1-1-3), a monomer (a1-2-6) and a monomer (1-17) as monomers, these monomers were mixed in a molar ratio of 19:25:38:18 [monomer (a1-4-2):monomer (a1-1-3):monomer (a1-2-6):monomer (1-17)]. This monomer mixture was mixed with methyl isobutyl ketone in the amount of 1.5 mass times the total mass of all monomers. To the mixture thus obtained, azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) as initiators were added in the amounts of 1.2 mol % and 3.6 mol % based on the total molar number of all monomers, and then polymerization was performed by heating at 73° C. for about 5 hours. Thereafter, an aqueous p-toluenesulfonic acid solution was added to the polymerization reaction solution, followed by stirring for 12 hours and further isolation through separation. The organic layer thus recovered was poured into a large amount of n-heptane to precipitate a resin, followed by filtration and recovery to obtain a resin A1 having a weight-average molecular weight of about 5.6×10.sup.3 in a yield of 62%. This resin A1 includes the following structural units (an elimination ratio of an ethoxyethyl group in all ethoxyethyl groups of the monomer (a1-4-2) and the monomer (1-17) is 100%).

##STR00272##

Example 8 [Synthesis of Resin A2]

[0816] Using a monomer (a1-4-2), a monomer (a1-1-3), a monomer (a1-2-6) and a monomer (1-17) as monomers, these monomers were mixed in a molar ratio of 19:25:38:18 [monomer (a1-4-2):monomer (a1-1-3):monomer (a1-2-6):monomer (1-17)]. This monomer mixture was mixed with methyl isobutyl ketone in the amount of 1.5 mass times the total mass of all monomers. To the mixture thus obtained, azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) as initiators were added in the amounts of 1.2 mol % and 3.6 mol % based on the total molar number of all monomers, and then polymerization was performed by heating at 73° C. for about 5 hours. Thereafter, the polymerization reaction solution was cooled to 15° C. and an aqueous p-toluenesulfonic acid solution was added, followed by stirring for 6 hours and further isolation through separation. The organic layer thus recovered was poured into a large amount of n-heptane to precipitate a resin, followed by filtration and recovery to obtain a resin A2 having a weight-average molecular weight of about 5.9×10.sup.3 in a yield of 58%. This resin A2 includes the following structural units (an elimination ratio of an ethoxyethyl group in all ethoxyethyl groups of the monomer (a1-4-2) and the monomer (I-17) is 72%).

##STR00273##

Example 9 [Synthesis of Resin A3]

[0817] Using a monomer (a1-1-3), a monomer (a1-2-6) and a monomer (1-17) as monomers, these monomers were mixed in a molar ratio of 25:38:37 [monomer (a1-1-3):monomer (a1-2-6):monomer (1-17)]. This monomer mixture was mixed with methyl isobutyl ketone in the amount of 1.5 mass times the total mass of all monomers. To the mixture thus obtained, azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) as initiators were added in the amounts of 1.2 mol % and 3.6 mol % based on the total molar number of all monomers, and then polymerization was performed by heating at 73° C. for about 5 hours. Thereafter, an aqueous p-toluenesulfonic acid solution was added to the polymerization reaction solution, followed by stirring for 12 hours and further isolation through separation. The organic layer thus recovered was poured into a large amount of n-heptane to precipitate a resin, followed by filtration and recovery to obtain a resin A3 having a weight-average molecular weight of about 5.5×10.sup.3 in a yield of 65%. This resin A3 includes the following structural units (an elimination ratio of an ethoxyethyl group in all ethoxyethyl groups of the monomer (1-17) is 100%).

##STR00274##

Example 10 [Synthesis of Resin A4]

[0818] Using a monomer (a1-4-2), a monomer (a1-1-3), a monomer (a1-2-6), a monomer (a2-1-3), a monomer (a3-4-2) and a monomer (1-17) as monomers, these monomers were mixed in a molar ratio of 12:20:35:3:15:15 [monomer (a1-4-2):monomer (a1-1-3):monomer (a1-2-6):monomer (a2-1-3):monomer (a3-4-2):monomer (1-17)]. This monomer mixture was mixed with methyl isobutyl ketone in the amount of 1.5 mass times the total mass of all monomers. To the mixture thus obtained, azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) as initiators were added in the amounts of 1.2 mol % and 3.6 mol % based on the total molar number of all monomers, and then polymerization was performed by heating at 73° C. for about 5 hours. Thereafter, an aqueous p-toluenesulfonic acid solution was added to the polymerization reaction solution, followed by stirring for 12 hours and further isolation through separation. The organic layer thus recovered was poured into a large amount of n-heptane to precipitate a resin, followed by filtration and recovery to obtain a resin A4 having a weight-average molecular weight of about 5.8×10.sup.3 in a yield of 63%. This resin A4 includes the following structural units (an elimination ratio of an ethoxyethyl group in all ethoxyethyl groups of the monomer (a1-4-2) and the monomer (1-17) is 100%).

##STR00275##

Example 11 [Synthesis of Resin A5]

[0819] Using a monomer (a1-1-3), a monomer (a1-2-6), a monomer (a2-1-3), a monomer (a3-4-2) and a monomer (1-17) as monomers, these monomers were mixed in a molar ratio of 20:35:3:15:27 [monomer (a1-1-3):monomer (a1-2-6):monomer (a2-1-3):monomer (a3-4-2):monomer (1-17)]. This monomer mixture was mixed with methyl isobutyl ketone in the amount of 1.5 mass times the total mass of all monomers. To the mixture thus obtained, azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) as initiators were added in the amounts of 1.2 mol % and 3.6 mol % based on the total molar number of all monomers, and then polymerization was performed by heating at 73° C. for about 5 hours. Thereafter, an aqueous p-toluenesulfonic acid solution was added to the polymerization reaction solution, followed by stirring for 12 hours and further isolation through separation. The organic layer thus recovered was poured into a large amount of n-heptane to precipitate a resin, followed by filtration and recovery to obtain a resin A5 having a weight-average molecular weight of about 5.4×10.sup.3 in a yield of 66%. This resin A5 includes the following structural units (an elimination ratio of an ethoxyethyl group in all ethoxyethyl groups of the monomer (1-17) is 100%).

##STR00276##

Example 12 [Synthesis of Resin A6]

[0820] Using a monomer (a1-4-2), a monomer (a1-1-3), a monomer (a1-2-6) and a monomer (1-25) as monomers, these monomers were mixed in a molar ratio of 19:25:38:18 [monomer (a1-4-2):monomer (a1-1-3):monomer (a1-2-6):monomer (1-25)]. This monomer mixture was mixed with methyl isobutyl ketone in the amount of 1.5 mass times the total mass of all monomers. To the mixture thus obtained, azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) as initiators were added in the amounts of 1.2 mol % and 3.6 mol % based on the total molar number of all monomers, and then polymerization was performed by heating at 73° C. for about 5 hours. Thereafter, an aqueous p-toluenesulfonic acid solution was added to the polymerization reaction solution, followed by stirring for 12 hours and further isolation through separation. The organic layer thus recovered was poured into a large amount of n-heptane to precipitate a resin, followed by filtration and recovery to obtain a resin A6 having a weight-average molecular weight of about 5.2×10.sup.3 in a yield of 59%. This resin A6 includes the following structural units (an elimination ratio of an ethoxyethyl group in all ethoxyethyl groups of the monomer (a1-4-2) and the monomer (1-25) is 100%).

##STR00277##

Example 13 [Synthesis of Resin A7]

[0821] Using a monomer (a1-4-2), a monomer (a1-1-3), a monomer (a1-2-6), a monomer (a2-1-3), a monomer (a3-4-2) and a monomer (1-25) as monomers, these monomers were mixed in a molar ratio of 12:20:35:3:15:15 [monomer (a1-4-2):monomer (a1-1-3):monomer (a1-2-6):monomer (a2-1-3):monomer (a3-4-2):monomer (1-25)]. This monomer mixture was mixed with methyl isobutyl ketone in the amount of 1.5 mass times the total mass of all monomers. To the mixture thus obtained, azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) as initiators were added in the amounts of 1.2 mol % and 3.6 mol % based on the total molar number of all monomers, and then polymerization was performed by heating at 73° C. for about 5 hours. Thereafter, an aqueous p-toluenesulfonic acid solution was added to the polymerization reaction solution, followed by stirring for 12 hours and further isolation through separation. The organic layer thus recovered was poured into a large amount of n-heptane to precipitate a resin, followed by filtration and recovery to obtain a resin A7 having a weight-average molecular weight of about 5.4×10.sup.3 in a yield of 61%. This resin A7 includes the following structural units (an elimination ratio of an ethoxyethyl group in all ethoxyethyl groups of the monomer (a1-4-2) and the monomer (1-25) is 100%).

##STR00278##

Example 14 [Synthesis of Resin A8]

[0822] Using a monomer (a1-4-2), a monomer (a1-1-3), a monomer (a1-2-6) and a monomer (1-33) as monomers, these monomers were mixed in a molar ratio of 19:25:38:18 [monomer (a1-4-2):monomer (a1-1-3):monomer (a1-2-6):monomer (1-33)]. This monomer mixture was mixed with methyl isobutyl ketone in the amount of 1.5 mass times the total mass of all monomers. To the mixture thus obtained, azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) as initiators were added in the amounts of 1.2 mol % and 3.6 mol % based on the total molar number of all monomers, and then polymerization was performed by heating at 73° C. for about 5 hours. Thereafter, an aqueous p-toluenesulfonic acid solution was added to the polymerization reaction solution, followed by stirring for 12 hours and further isolation through separation. The organic layer thus recovered was poured into a large amount of n-heptane to precipitate a resin, followed by filtration and recovery to obtain a resin A8 having a weight-average molecular weight of about 5.2×10.sup.3 in a yield of 60%. This resin A8 includes the following structural units.

##STR00279##

Example 15 [Synthesis of Resin A9]

[0823] Using a monomer (a1-1-3), a monomer (a1-2-6) and a monomer (1-33) as monomers, these monomers were mixed in a molar ratio of 25:38:37 [monomer (a1-1-3):monomer (a1-2-6):monomer (1-33)]. This monomer mixture was mixed with methyl isobutyl ketone in the amount of 1.5 mass times the total mass of all monomers. To the mixture thus obtained, azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) as initiators were added in the amounts of 1.2 mol % and 3.6 mol % based on the total molar number of all monomers, and then polymerization was performed by heating at 73° C. for about 5 hours. Thereafter, the polymerization reaction solution was poured into a large amount of n-heptane to precipitate a resin, followed by filtration and recovery to obtain a resin A9 having a weight-average molecular weight of about 5.0×10.sup.3 in a yield of 65%. This resin A9 includes the following structural units.

##STR00280##

Example 16 [Synthesis of Resin A10]

[0824] Using acetoxystyrene, a monomer (a1-1-3), a monomer (a1-2-6) and a monomer (1-43) as monomers, these monomers were mixed in a molar ratio of 37:20:32:11 [acetoxystyrene:monomer (a1-1-3):monomer (a1-2-6):monomer (I-43)]. This monomer mixture was mixed with methyl isobutyl ketone in the amount of 1.5 mass times the total mass of all monomers. To the mixture thus obtained, azobisisobutyronitrile as an initiator was added in the amount of 7 mol % based on the total molar number of all monomers, and then polymerization was performed by heating at 85° C. for about 5 hours. Thereafter, an aqueous 25% tetramethylammonium hydroxide solution was added to the polymerization reaction solution, followed by stirring for 12 hours and further isolation through separation. The organic layer thus recovered was poured into a large amount of n-heptane to precipitate a resin, followed by filtration and recovery to obtain a resin A10 (copolymer) having a weight-average molecular weight of about 5.3×10.sup.3 in a yield of 62%. This resin A10 includes the following structural units.

##STR00281##

Example 17 [Synthesis of Resin A11]

[0825] Using a monomer (a1-4-2), a monomer (a1-1-3), a monomer (a1-2-6), a monomer (a2-1-3), a monomer (a3-4-2) and a monomer (1-33) as monomers, these monomers were mixed in a molar ratio of 12:20:35:3:15:15 [monomer (a1-4-2):monomer (a1-1-3):monomer (a1-2-6):monomer (a2-1-3):monomer (a3-4-2):monomer (1-33)]. This monomer mixture was mixed with methyl isobutyl ketone in the amount of 1.5 mass times the total mass of all monomers. To the mixture thus obtained, azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) as initiators were added in the amounts of 1.2 mol % and 3.6 mol % based on the total molar number of all monomers, and then polymerization was performed by heating at 73° C. for about 5 hours. Thereafter, an aqueous p-toluenesulfonic acid solution was added to the polymerization reaction solution, followed by stirring for 12 hours and further isolation through separation. The organic layer thus recovered was poured into a large amount of n-heptane to precipitate a resin, followed by filtration and recovery to obtain a resin A11 having a weight-average molecular weight of about 5.1×10.sup.3 in a yield of 62%. This resin A11 includes the following structural units.

##STR00282##

Example 18 [Synthesis of Resin A12]

[0826] Using a monomer (a1-1-3), a monomer (a1-2-6), a monomer (a2-1-3), a monomer (a3-4-2) and a monomer (1-33) as monomers, these monomers were mixed in a molar ratio of 20:35:3:15:27 [monomer (a1-1-3):monomer (a1-2-6):monomer (a2-1-3):monomer (a3-4-2):monomer (1-33)]. This monomer mixture was mixed with methyl isobutyl ketone in the amount of 1.5 mass times the total mass of all monomers. To the mixture thus obtained, azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) as initiators were added in the amounts of 1.2 mol % and 3.6 mol % based on the total molar number of all monomers, and then polymerization was performed by heating at 73° C. for about 5 hours. Thereafter, the polymerization reaction solution was poured into a large amount of n-heptane to precipitate a resin, followed by filtration and recovery to obtain a resin A12 having a weight-average molecular weight of about 5.2×10.sup.3 in a yield of 64%. This resin A12 includes the following structural units.

##STR00283##

Example 19 [Synthesis of Resin A13]

[0827] Using a monomer (a1-4-2), a monomer (a1-1-3), a monomer (a1-2-6) and a monomer (1-68) as monomers, these monomers were mixed in a molar ratio of 19:25:38:18 [monomer (a1-4-2):monomer (a1-1-3):monomer (a1-2-6):monomer (1-68)]. This monomer mixture was mixed with methyl isobutyl ketone in the amount of 1.5 mass times the total mass of all monomers. To the mixture thus obtained, azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) as initiators were added in the amounts of 1.2 mol % and 3.6 mol % based on the total molar number of all monomers, and then polymerization was performed by heating at 73° C. for about 5 hours. Thereafter, the polymerization reaction solution was poured into a large amount of n-heptane to precipitate a resin, followed by filtration and recovery to obtain a resin A13 having a weight-average molecular weight of about 5.3×10.sup.3 in a yield of 60%. This resin A13 includes the following structural units.

##STR00284##

Example 20 [Synthesis of Resin A14]

[0828] Using acetoxystyrene, a monomer (a1-1-3), a monomer (a1-2-6) and a monomer (1-67) as monomers, these monomers were mixed in a molar ratio of 37:20:32:11 [acetoxystyrene:monomer (a1-1-3):monomer (a1-2-6):monomer (I-67)]. This monomer mixture was mixed with methyl isobutyl ketone in the amount of 1.5 mass times the total mass of all monomers. To the mixture thus obtained, azobisisobutyronitrile as an initiator was added in the amount of 7 mol % based on the total molar number of all monomers, and then polymerization was performed by heating at 85° C. for about 5 hours. Thereafter, an aqueous 25% tetramethylammonium hydroxide solution was added to the polymerization reaction solution, followed by stirring for 12 hours and further isolation through separation. The organic layer thus recovered was poured into a large amount of n-heptane to precipitate a resin, followed by filtration and recovery to obtain a resin A14 having a weight-average molecular weight of about 5.2×10.sup.3 in a yield of 63%. This resin A14 includes the following structural units.

##STR00285##

Example 21 [Synthesis of Resin A15]

[0829] Using a monomer (a1-4-2), a monomer (a1-1-3), a monomer (a1-2-6) and a monomer (1-37) as monomers, these monomers were mixed in a molar ratio of 19:25:38:18 [monomer (a1-4-2):monomer (a1-1-3):monomer (a1-2-6):monomer (1-37)]. This monomer mixture was mixed with methyl isobutyl ketone in the amount of 1.5 mass times the total mass of all monomers. To the mixture thus obtained, azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) as initiators were added in the amounts of 1.2 mol % and 3.6 mol % based on the total molar number of all monomers, and then polymerization was performed by heating at 73° C. for about 5 hours. Thereafter, an aqueous p-toluenesulfonic acid solution was added to the polymerization reaction solution, followed by stirring for 12 hours and further isolation through separation. The organic layer thus recovered was poured into a large amount of n-heptane to precipitate a resin, followed by filtration and recovery to obtain a resin A15 having a weight-average molecular weight of about 5.3×10.sup.3 in a yield of 63%. This resin A15 includes the following structural units.

##STR00286##

Example 22 [Synthesis of Resin A16]

[0830] Using a monomer (a1-1-3), a monomer (a1-2-6) and a monomer (1-37) as monomers, these monomers were mixed in a molar ratio of 25:38:37 [monomer (a1-1-3):monomer (a1-2-6):monomer (1-37)]. This monomer mixture was mixed with methyl isobutyl ketone in the amount of 1.5 mass times the total mass of all monomers. To the mixture thus obtained, azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) as initiators were added in the amounts of 1.2 mol % and 3.6 mol % based on the total molar number of all monomers, and then polymerization was performed by heating at 73° C. for about 5 hours. Thereafter, the polymerization reaction solution was poured into a large amount of n-heptane to precipitate a resin, followed by filtration and recovery to obtain a resin A16 having a weight-average molecular weight of about 5.2×10.sup.3 in a yield of 61%. This resin A16 includes the following structural units.

##STR00287##

Example 23 [Synthesis of Resin A17]

[0831] Using acetoxystyrene, a monomer (a1-1-3), a monomer (a1-2-6) and a monomer (1-49) as monomers, these monomers were mixed in a molar ratio of 37:20:32:11 [acetoxystyrene:monomer (a1-1-3):monomer (a1-2-6):monomer (I-49)]. This monomer mixture was mixed with methyl isobutyl ketone in the amount of 1.5 mass times the total mass of all monomers. To the mixture thus obtained, azobisisobutyronitrile as an initiator was added in the amounts of 7 mol % based on the total molar number of all monomers, and then polymerization was performed by heating at 85° C. for about 5 hours. Thereafter, an aqueous 25% tetramethylammonium hydroxide solution was added to the polymerization reaction solution, followed by stirring for 12 hours and further isolation through separation. The organic layer thus recovered was poured into a large amount of n-heptane to precipitate a resin, followed by filtration and recovery to obtain a resin A17 (copolymer) having a weight-average molecular weight of about 5.5×10.sup.3 in a yield of 60%. This resin A17 includes the following structural units.

##STR00288##

Example 24 [Synthesis of Resin A18]

[0832] Using a monomer (a1-4-2), a monomer (a1-1-3), a monomer (a1-2-6), a monomer (a2-1-3), a monomer (a3-4-2) and a monomer (1-37) as monomers, these monomers were mixed in a molar ratio of 12:20:35:3:15:15 [monomer (a1-4-2):monomer (a1-1-3):monomer (a1-2-6):monomer (a2-1-3):monomer (a3-4-2):monomer (1-37)]. This monomer mixture was mixed with methyl isobutyl ketone in the amount of 1.5 mass times the total mass of all monomers. To the mixture thus obtained, azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) as initiators were added in the amounts of 1.2 mol % and 3.6 mol % based on the total molar number of all monomers, and then polymerization was performed by heating at 73° C. for about 5 hours. Thereafter, an aqueous p-toluenesulfonic acid solution was added to the polymerization reaction solution, followed by stirring for 12 hours and further isolation through separation. The organic layer thus recovered was poured into a large amount of n-heptane to precipitate a resin, followed by filtration and recovery to obtain a resin A18 having a weight-average molecular weight of about 5.2×10.sup.3 in a yield of 60%. This resin A18 includes the following structural units.

##STR00289##

Example 25 [Synthesis of Resin A19]

[0833] Using a monomer (a1-1-3), a monomer (a1-2-6), a monomer (a2-1-3), a monomer (a3-4-2) and a monomer (1-37) as monomers, these monomers were mixed in a molar ratio of 20:35:3:15:27 [monomer (a1-1-3):monomer (a1-2-6):monomer (a2-1-3):monomer (a3-4-2):monomer (1-37)]. This monomer mixture was mixed with methyl isobutyl ketone in the amount of 1.5 mass times the total mass of all monomers. To the mixture thus obtained, azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) as initiators were added in the amounts of 1.2 mol % and 3.6 mol % based on the total molar number of all monomers, and then polymerization was performed by heating at 73° C. for about 5 hours. Thereafter, the polymerization reaction solution was poured into a large amount of n-heptane to precipitate a resin, followed by filtration and recovery to obtain a resin A19 having a weight-average molecular weight of about 5.3×10.sup.3 in a yield of 63%. This resin A19 includes the following structural units.

##STR00290##

Example 26 [Synthesis of Resin A20]

[0834] Using a monomer (a1-1-3), a monomer (a1-2-6) and a monomer (1-71) as monomers, these monomers were mixed in a molar ratio of 25:38:37 [monomer (a1-1-3):monomer (a1-2-6):monomer (1-71)]. This monomer mixture was mixed with methyl isobutyl ketone in the amount of 1.5 mass times the total mass of all monomers. To the mixture thus obtained, azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) as initiators were added in the amounts of 1.2 mol % and 3.6 mol % based on the total molar number of all monomers, and then polymerization was performed by heating at 73° C. for about 5 hours. Thereafter, the polymerization reaction solution was poured into a large amount of n-heptane to precipitate a resin, followed by filtration and recovery to obtain a resin A20 having a weight-average molecular weight of about 5.5×10.sup.3 in a yield of 58%. This resin A20 includes the following structural units.

##STR00291##

Example 27 [Synthesis of Resin A21]

[0835] Using acetoxystyrene, a monomer (a1-1-3), a monomer (a1-2-6) and a monomer (1-81) as monomers, these monomers were mixed in a molar ratio of 37:20:32:11 [acetoxystyrene:monomer (a1-1-3):monomer (a1-2-6):monomer (I-81)]. This monomer mixture was mixed with methyl isobutyl ketone in the amount of 1.5 mass times the total mass of all monomers. To the mixture thus obtained, azobisisobutyronitrile as an initiator was added in the amount of 7 mol % based on the total molar number of all monomers, and then polymerization was performed by heating at 85° C. for about 5 hours. Thereafter, an aqueous 25% tetramethylammonium hydroxide solution was added to the polymerization reaction solution, followed by stirring for 12 hours and further isolation through separation. The organic layer thus recovered was poured into a large amount of n-heptane to precipitate a resin, followed by filtration and recovery to obtain a resin A21 having a weight-average molecular weight of about 5.7×10.sup.3 in a yield of 55%. This resin A21 includes the following structural units.

##STR00292##

Example 28 [Synthesis of Resin A22]

[0836] Using a monomer (a1-1-3), a monomer (a1-2-6), a monomer (a2-1-3), a monomer (a3-4-2) and a monomer (1-71) as monomers, these monomers were mixed in a molar ratio of 20:35:3:15:27 [monomer (a1-1-3):monomer (a1-2-6):monomer (a2-1-3):monomer (a3-4-2):monomer (1-71)]. This monomer mixture was mixed with methyl isobutyl ketone in the amount of 1.5 mass times the total mass of all monomers. To the mixture thus obtained, azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) as initiators were added in the amounts of 1.2 mol % and 3.6 mol % based on the total molar number of all monomers, and then polymerization was performed by heating at 73° C. for about 5 hours. Thereafter, the polymerization reaction solution was poured into a large amount of n-heptane to precipitate a resin, followed by filtration and recovery to obtain a resin A22 having a weight-average molecular weight of about 5.4×10.sup.3 in a yield of 59%. This resin A22 includes the following structural units.

##STR00293##

Synthesis Example 5 [Synthesis of Resin AX1]

[0837] Using a monomer (ax-1), a monomer (ax-2) and a monomer (1-17) as monomers, these monomers were mixed in a molar ratio of 30:30:40 [monomer (ax-1):monomer (ax-2):monomer (I-17)]. This monomer mixture was mixed with methyl isobutyl ketone in the amount of 1.5 mass times the total mass of all monomers. To the mixture thus obtained, azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile) as initiators were added in the amounts of 1.2 mol % and 3.6 mol % based on the total molar number of all monomers, and then polymerization was performed by heating at 73° C. for about 5 hours. Thereafter, an aqueous p-toluenesulfonic acid solution was added to the polymerization reaction solution, followed by stirring for 12 hours and further isolation through separation. The organic layer thus recovered was poured into a large amount of n-heptane to precipitate a resin, followed by filtration and recovery to obtain a resin AX1 having a weight-average molecular weight of about 5.4×10.sup.3 in a yield of 66%. This resin AX1 includes the following structural units (an elimination ratio of an ethoxyethyl group in all ethoxyethyl groups of the monomer (1-17) is 100%).

##STR00294##

<Preparation of Resist Composition>

[0838] A mixture obtained by mixing and dissolving the respective components shown in Table 1 was filtered through a fluororesin filter having a pore diameter of 0.2 μm to prepare resist compositions.

TABLE-US-00001 TABLE 1 Resist composition Resin Acid generator(B) Quencher(C) PB/PEB Composition 1  A1 = 10 parts B1-43 = 3.4 parts C1 = 0.7 parts 110° C./120° C. Composition 2  A2 = 10 parts B1-43 = 3.4 parts C1 = 0.7 parts 110° C./120° C. Composition 3  A3 = 10 parts B1-43 = 3.4 parts C1 = 0.7 parts 110° C./120° C. Composition 4  A4 = 10 parts B1-43 = 3.4 parts C1 = 0.7 parts 110° C./120° C. Composition 5  A5 = 10 parts B1-43 = 3.4 parts C1 = 0.7 parts 110° C./120° C. Composition 6  A6 = 10 parts B1-43 = 3.4 parts C1 = 0.7 parts 110° C./120° C. Composition 7  A7 = 10 parts B1-43 = 3.4 parts C1 = 0.7 parts 110° C./120° C. Composition 8  A8 = 10 parts B1-43 = 3.4 parts C1 = 0.7 parts 110° C./120° C. Composition 9  A9 = 10 parts B1-43 = 3.4 parts C1 = 0.7 parts 110° C./120° C. Composition 10 A10 = 10 parts B1-43 = 3.4 parts C1 = 0.7 parts 110° C./120° C. Composition 11 A11 = 10 parts B1-43 = 3.4 parts C1 = 0.7 parts 110° C./120° C. Composition 12 A12 = 10 parts B1-43 = 3.4 parts C1 = 0.7 parts 110° C./120° C. Composition 13 A13 = 10 parts B1-43 = 3.4 parts C1 = 0.7 parts 110° C./120° C. Composition 14 A14 = 10 parts B1-43 = 3.4 parts C1 = 0.7 parts 110° C./120° C. Composition 15 A15 = 10 parts B1-43 = 3.4 parts C1 = 0.7 parts 110° C./120° C. Composition 16 A16 = 10 parts B1-43 = 3.4 parts C1 = 0.7 parts 110° C./120° C. Composition 17 A17 = 10 parts B1-43 = 3.4 parts C1 = 0.7 parts 110° C./120° C. Composition 18 A18 = 10 parts B1-43 = 3.4 parts C1 = 0.7 parts 110° C./120° C. Composition 19 A19 = 10 parts B1-43 = 3.4 parts C1 = 0.7 parts 110° C./120° C. Composition 20 A20 = 10 parts B1-43 = 3.4 parts C1 = 0.7 parts 110° C./120° C. Composition 21 A21 = 10 parts B1-43 = 3.4 parts C1 = 0.7 parts 110° C./120° C. Composition 22 A22 = 10 parts B1-43 = 3.4 parts C1 = 0.7 parts 110° C./120° C. Comparative AX1 = 10 parts B1-43 = 3.4 parts C1 = 0.7 parts 110° C./120° C. Composition 1

<Resin>

[0839] A1 to A22, AX1: Resin A1 To Resin A22, Resin AX1

<Acid Generator (B)>

[0840] B1-43: Salt represented by formula (B1-43) (synthesized in accordance with Examples of JP 2016-47815 A)

##STR00295##

<Quencher (C)>

[0841] C1: synthesized by the method mentioned in JP 2011-39502 A

##STR00296##

<Solvent>

[0842]

TABLE-US-00002 Propylene glycol monomethyl ether acetate 400 parts Propylene glycol monomethyl ether 150 parts γ-Butyrolactone   5 parts
(Evaluation of Exposure of Resist Composition with Electron Beam: Alkaline Development)

[0843] Each 6 inch-diameter silicon wafer was treated with hexamethyldisilazane on a direct hot plate at 90° C. for 60 seconds. A resist composition was spin-coated on the silicon wafer in such a manner that the thickness of the composition layer became 0.04 μm. The coated silicon wafer was prebaked on the direct hot plate at the temperature shown in the column “PB” of Table 1 for 60 seconds to form a composition layer. Using an electron-beam direct-write system (“HL-800D 50 keV”, manufactured by Hitachi, Ltd.), a line-and-space pattern was directly written on the composition layer formed on the wafer while changing the exposure dose stepwise.

[0844] After the exposure, post-exposure baking was performed on the hot plate at the temperature shown in the column “PEB” of Table 1 for 60 seconds, followed by paddle development with an aqueous 2.38% by mass tetramethylammonium hydroxide solution for 60 seconds to obtain a resist pattern.

[0845] The resist pattern (line-and-space pattern) thus obtained was observed by a scanning electron microscope and effective sensitivity was defined as the exposure dose at which a ratio of a line width to a space width of a 60 nm line-and-space pattern became 1:1.

[0846] Evaluation of Line Edge Roughness (LER): Line edge roughness was determined by measuring a roughness width of the irregularity in side wall surface of resist pattern produced at the effective sensitivity using a scanning electron microscope. The results are shown in Table 2.

TABLE-US-00003 TABLE 2 Composition LER Example 29 Composition 1 3.68 Example 30 Composition 2 3.88 Example 31 Composition 3 3.71 Example 32 Composition 4 3.76 Example 33 Composition 5 3.75 Example 34 Composition 6 3.65 Example 35 Composition 7 3.74 Example 36 Composition 8 3.58 Example 37 Composition 9 3.56 Example 38 Composition 10 3.61 Example 39 Composition 11 3.64 Example 40 Composition 12 3.62 Example 41 Composition 13 3.65 Example 42 Composition 14 3.74 Example 43 Composition 15 3.54 Example 44 Composition 16 3.52 Example 45 Composition 17 3.58 Example 46 Composition 18 3.61 Example 47 Composition 19 3.59 Example 48 Composition 20 3.63 Example 49 Composition 21 3.69 Example 50 Composition 22 3.68 Comparative Comparative Failing to pattern Example 1 Composition 1 formation
(Evaluation of Exposure of Resist Composition with Electron Beam: Butyl Acetate Development)

[0847] Each 6 inch-diameter silicon wafer was treated with hexamethyldisilazane on a direct hot plate at 90° C. for 60 seconds. A resist composition was spin-coated on the silicon wafer in such a manner that the thickness of the composition layer became 0.04 μm. The coated silicon wafer was prebaked on the direct hot plate at the temperature shown in the column “PB” of Table 1 for 60 seconds to form a composition layer. Using an electron-beam direct-write system (“HL-800D 50 keV”, manufactured by Hitachi, Ltd.), a line-and-space pattern was directly written on the composition layer formed on the wafer while changing the exposure dose stepwise.

[0848] After the exposure, post-exposure baking was performed on the hot plate at the temperature shown in the column “PEB” of Table 1 for 60 seconds, and then the composition layer on the silicon wafer was developed with butyl acetate (manufactured by Tokyo Chemical Industry Co., Ltd.) as a developing solution at 23° C. for 20 seconds by the dynamic dispense method to obtain a resist pattern.

[0849] The resist pattern (line-and-space pattern) thus obtained was observed by a scanning electron microscope and effective sensitivity was defined as the exposure dose at which a ratio of a line width to a space width of a 60 nm line-and-space pattern became 1:1.

[0850] Evaluation of Line Edge Roughness (LER): Line edge roughness was determined by measuring a roughness width of the irregularity in side wall surface of resist pattern produced at the effective sensitivity using a scanning electron microscope. The results are shown in Table 3.

TABLE-US-00004 TABLE 3 Composition LER Example 51 Composition 1 3.84 Example 52 Composition 2 3.92 Example 53 Composition 3 3.81 Example 54 Composition 4 3.71 Example 55 Composition 5 3.69 Example 56 Composition 6 3.81 Example 57 Composition 7 3.62 Example 58 Composition 8 3.66 Example 59 Composition 9 3.62 Example 60 Composition 10 3.69 Example 61 Composition 11 3.55 Example 62 Composition 12 3.52 Example 63 Composition 13 3.79 Example 64 Composition 14 3.81 Example 65 Composition 15 3.62 Example 66 Composition 16 3.59 Example 67 Composition 17 3.67 Example 68 Composition 18 3.52 Example 69 Composition 19 3.47 Example 70 Composition 20 3.61 Example 71 Composition 21 3.66 Example 72 Composition 22 3.49 Comparative Comparative Failing to pattern Example 2 Composition 1 formation

INDUSTRIAL APPLICABILITY

[0851] The resist composition including the resin of the present invention is suited for fine processing of semiconductors because of obtaining a resist pattern with satisfactory line edge roughness (LER), and thus it is industrially very useful.