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[Chemical Formula 12] 

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[0186] In the formula, Ra’$^{1 }$and Ra’$^{2 }$represents a hydrogen atom or an alkyl group; and Ra’ 3 represents a hydrocarbon group, provided that Ra’ 3 may be bonded to Rail or Ra’ 2 . 

[0187] In the formula (al-r-1), it is preferable that at least one of Rail and Ra’ 2 represents a hydrogen atom, and it is more preferable that both of Rail and Ra’ 2 represent a hydrogen atom. 2 

[0188] In the case where Rail or Ra’ is an alkyl group, as the alkyl group, the same alkyl groups as those described above the for the substituent which may be bonded to the carbon atom on the a-position of the aforementioned a-sub› stituted acrylate ester can be mentioned, and an alkyl group of 1 to 5 carbon atoms is preferable. Specific examples include linear or branched alkyl groups. Specific examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an iso› pentyl group and a neopentyl group. Of these, a methyl group or an ethyl group is preferable, and a methyl group is particularly preferable. 

[0189] In formula (al-r-1), examples of the hydrocarbon group for Ra’ 3 include a linear or branched alkyl group and a cyclic hydrocarbon group. 

[0190] The linear alkyl group preferably has 1 to 5 carbon atoms, more preferably 1 to 4, and still more preferably 1 or 2. Specific examples include a methyl group, an ethyl group, an n-propyl group, an n-butyl group and an n-pentyl group. Among these, a methyl group, an ethyl group or an n-butyl group is preferable, and a methyl group or an ethyl group is more preferable. 

[0191] The branched alkyl group preferably has 3 to 10 carbon atoms, and more preferably 3 to 5. Specific examples include an isopropyl group, an isobutyl group, a tert-butyl group, an isopentyl group, a neopentyl group a 1,1-diethyl› propyl group and a 2,2-dimethylbutyl group. Among these, an isopropyl group is preferable. 3 

[0192] In the case where Ra’ represents a cyclic hydro› carbon group, the cyclic hydrocarbon group may be an aliphatic hydrocarbon group or an aromatic hydrocarbon group, and may be polycyclic or monocyclic. 

[0193] As the monocyclic aliphatic hydrocarbon group, a group in which 1 hydrogen atom has been removed from a monocycloalkane is preferable. The monocycloalkane pref› erably has 3 to 6 carbon atoms, and specific examples thereof include cyclopentane and cyclohexane. 

[0194] As the polycyclic aliphatic hydrocarbon group, a group in which 1 hydrogen atom has been removed from a polycycloalkane is preferable, and the polycyclic group preferably has 7 to 12 carbon atoms. Examples of the polycycloalkane include adamantane, norbomane, isob› omane, tricyclodecane and tetracyclododecane. 3 

[0195] When the monovalent hydrocarbon group for Ra’ is an aromatic hydrocarbon group, the aromatic hydrocarbon group is a hydrocarbon group having at least one aromatic ring. 

[0196] The aromatic ring is not particularly limited, as long as it is a cyclic conjugated compound having (4n+2)it electrons, and may be either monocyclic or polycyclic. The aromatic ring preferably has 5 to 30 carbon atoms, more preferably 5 to 20, still more preferably 6 to 15, and most preferably 6 to 12. Examples of the aromatic ring include aromatic hydrocarbon rings, such as benzene, naphthalene, anthracene and phenanthrene; and aromatic hetero rings in which part of the carbon atoms constituting the aforemen› tioned aromatic hydrocarbon rings has been substituted with a hetero atom. Examples of the hetero atom within the aromatic hetero rings include an oxygen atom, a sulfur atom and a nitrogen atom. Specific examples of the aromatic hetero ring include a pyridine ring and a thiophene ring. 

[0197] Specific examples of the aromatic hydrocarbon group for Ra’ 3 include a group in which one hydrogen atom has been removed from the aforementioned aromatic hydro› carbon ring or aromatic hetero ring (aryl group or heteroaryl group); a group in which one hydrogen atom has been removed from an aromatic compound having two or more aromatic rings (biphenyl, fluorene or the like); and a group in which one hydrogen atom of the aforementioned aromatic hydrocarbon ring or aromatic hetero ring has been substi› tuted with an alkylene group (an arylalkyl group such as a benzyl group, a phenethyl group, a 1-naphthylmethyl group, a 2-naphthylmethyl group, a 1-naphthylethyl group, or a 2-naphthylethyl group). The alkylene group bonded to the aforementioned aromatic hydrocarbon ring or the aromatic hetero ring preferably has 1 to 4 carbon atoms, more preferably 1 or 2 carbon atoms, and most preferably 1 carbon atom. 3 2 

[0198] In the case where Ra’ is bonded to Rail or Ra’ to form a ring, the cyclic group is preferably a 4 to 7-membered ring, and more preferably a 4 to 6-membered ring. Specific examples of the cyclic group include tetrahydropyranyl group and tetrahydrofuranyl group. 

[0199] -Tertiary Alkyl Ester-Type Acid Dissociable Group 

[0200] Examples of the acid dissociable group for protect› ing the carboxy group as a polar group include the acid dissociable group represented by general formula (al-r-2) shown below. Among the acid dissociable groups repre› sented by general formula (al-r-2), for convenience, a group which is constituted of alkyl groups is referred to as "tertiary ester-type acid dissociable group". 

[Chemical Formula 13] 

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In the formula, Ra’ 4 to Ra’$^{6 }$each independently represents a hydrocarbon group, provided that Ra’s and Ra’ 6 may be mutually bonded to form a ring. 6 

[0201] As the hydrocarbon group for Ra’$^{4 }$to Ra’ , the same groups as those described above for Ra’ 3 can be mentioned. 4 

[0202] Ra’ is preferably an alkyl group of 1 to 5 carbon atoms. In the case where Ra’s and Ra’ $^{6 }$are mutually bonded to form a ring, a group represented by general formula (al-r2-1) shown below can be mentioned. On the other hand, 

