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present invention, contains a repeating unit represented by formula (I) and a repeating unit represented by formula (II): 

<img src='content_image/902822.jpg'>

<img src='content_image/902823.jpg'>

wherein 

R$_{1 }$ represents a hydrogen atom, a methyl group, a cyano group, a halogen atom or a perfluoro group, 

R$_{2 }$ represents a non-acid-decomposable group, 

X represents a hydrogen atom or an organic group, 

m represents an integer of 1 to 4, 

n represents an integer of 1 to 4, provided that 2~n+m~5, 

p represents an integer of 1 to 4, 

when m or p is an integer of 2 to 4, multiple Xs may be the same or different, 

whenn is an integer of2 to 4, multiple R$_{2}$s may be the same or different, and 

R$_{1 }$ and X in formula (II) may be the same as or different from R$_{1 }$ and X in formula (I), respectively. 

The perfluoro group ofR$_{1 }$ is preferably a perfluoromethyl group or a perfluoroethyl group. R$_{1 }$ is preferably a hydrogen atom, a methyl group or a CmF $_{2}$m+l group (mis preferably 1 ), more preferably a hydrogen atom or a methyl group. 

R$_{2 }$ represents a non-acid-decomposable group. The non› acid-decomposable group means a group which is not an acid-decomposable group ( a group of decomposing under the action of an acid to generate an alkali-soluble group), that is, a group which does not produce an alkali-soluble group such as hydroxyl group and carboxyl group by decomposing under the action of an acid generated from a photoacid generator or the like upon exposure. 

Examples of the non-acid-decomposable group of R$_{2 }$ include a halogen atom, an alkyl group, a cycloalkyl group, an aryl group, an alkoxy group, an acyl group, ---OC(=O)Ra, -OC(=O)ORa, ----C(=O)ORa, ----C(=O)N(Rb)Ra, -N(Rb)C(=O)Ra, -N(Rb)C(=O)ORa, -N(Rb)S0$_{2}$Ra, -SRa, -S0$_{2}$Ra, -S0$_{3}$Ra and-S0$_{2}$N(Rb)Ra. A hydro- gen atom is not included in the non-acid-decomposable group. 

Ra represents an alkyl group, a cycloalkyl group or an aryl group. 

Rb represents a hydrogen atom, an alkyl group, a cycloalkyl group or an aryl group. 

The alkyl group of R$_{2 }$ is, for example, an alkyl group having from 1 to 8 carbon atoms and specific preferred examples thereof include a methyl group, an ethyl group, a propyl group, an n-butyl group, a sec-butyl group, a hexyl group and an octyl group. 

The cycloalkyl group of R$_{2 }$ is, for example, a cycloalkyl group having from 3 to 15 carbon atoms and specific pre› ferred examples thereof include a cyclopentyl group, a cyclo- hexyl group, a norbornyl group and an adamantyl group. 

(I) 

The alkoxy group of R$_{2 }$ is, for example, an alkoxy group having from 1 to 8 carbon atoms and examples thereof include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, a hexyloxy group and a cyclohexyloxy group. 

The aryl group ofR$_{2 }$ is, for example, an aryl group having from 6 to 15 carbon atoms and specific preferred examples thereof include a phenyl group, a tolyl group, a naphthyl group and an anthryl group. 

(II) 

The acyl group ofR$_{2 }$ is, for example, an acyl group having from 2 to 8 carbon atoms and specific preferred examples thereof include a formyl group, an acetyl group, a propanoyl group, a butanoyl group, a pivaloyl group and a benzoyl group. 

These groups each may have a substituent and preferred examples of the substituent include a hydroxyl group, a car› boxyl group, a halogen atom (e.g., fluorine, chlorine, bro› mine, iodine) and an alkoxy group ( e.g., methoxy, ethoxy, propoxy, butoxy ). In the case of a cyclic structure, examples of the substituent further include an alkyl group (preferably having from 1 to 8 carbon atoms). 

The alkyl group, cycloalkyl group and aryl group of Ra and Rb are the same as those described for R$_{2}$ . 

The organic group of X is preferably an organic group having from 1 to 40 carbon atoms and may be an acid› decomposable group or a non-acid-decomposable group. 

In the case of anon-acid-decomposable group, examples of the organic group include the same organic groups as those for the non-acid-decomposable group ofR$_{2 }$ (since this is an organic group, a halogen atom is not included). 

Also, examples thereofinclude an alkyl group, a cycloalkyl group, an alkenyl group, an aryl group, an alkyloxy group (excluding -0-tertiary alkyl group), an acyl group, a cycloalkyloxy group, an alkenyloxy group, an aryloxy group, an alkylcarbonyloxy group, an alkylamidomethyloxy group, an alkylamide group, an arylamidomethyl group and an ary› lamide group. 

Of these non-acid-decomposable groups, preferred are an acyl group, an alkylcarbonyloxy group, an alkyloxy group, a cycloalkyloxy group, an aryloxy group, an alkylamideoxy group and an alkylamide group, and more preferred are an acyl group, an alkylcarbonyloxy group, an alkyloxy group, a cycloalkyloxy group and an aryloxy group are. 

In the non-acid-decomposable group, the alkyl group is preferably an alkyl group having from 1 to 4 carbon atoms, such as methyl group, ethyl group, propyl group, n-butyl group, sec-butyl group and tert-butyl group; the cycloalkyl group is preferably a cycloalkyl group having from 3 to 10 carbon atoms, such as cyclopropyl group, cyclobutyl group, cyclohexyl group and adamantyl group; the alkenyl group is preferably an alkenyl group having from 2 to 4 carbon atoms, such as vinyl group, propenyl group, ally! group and butenyl group; the aryl group is preferably an aryl group having from 6 to 14 carbon atoms, such as phenyl group, xylyl group, toluyl group, cumenyl group, naphthyl group and anthracenyl group; and the alkoxy group is preferably an alkoxy group having from 1 to 4 carbon atoms, such as methoxy group, ethoxy group, hydroxyethoxy group, propoxy group, hydrox› ypropoxy group, n-butoxy group, isobutoxy group and sec› butoxy group. 

