91  US 9,958,775 B2  92  -continued  The content rate of the repeating units having the acid› decomposable groups in the compound (B2) is preferably  from 5 to 95% by mo!, more preferably from 10 to 60% by  mo!, and particularly preferably 15 to 50% by mo!, in the  total repeating units.  In addition, the compound (B2) may be copolymerized  with other appropriate polymerizable monomers so that an  alkali-soluble group, for example, a phenolic hydroxyl  group or a carboxyl group can be introduced for the purpose  of maintaining good developability with an alkali developer,  or may be copolymerized with other hydrophobic polymer› izable monomers such as alkyl acrylate and alkyl methacry› late for the purpose of enhancing the film quality.  In one embodiment, the compound (B2) preferably con› tains a repeating unit represented by the following general  formula (A).  [Chem. 60]  (A)  In the formula (A),  R$_{41}$ , R 42 , and R $_{43 }$each independently represent a hydro› gen atom, an alkyl group, a halogen atom, a cyano  group, or an alkoxycarbonyl group. However, R$_{42 }$may  be bonded to Ar$_{4 }$ to form a ring, in this case, R$_{42 }$ represents a single bond or an alkylene group.  X$_{4 }$ represents a single bond, --COO-, or -CONR$_{64}$- and R$_{64 }$ represents a hydrogen atom, and an alkyl  group.  L$_{4 }$ represents a single bond and an alkylene group.  Specific examples of the alkyl group, the cycloalkyl  group, the halogen atom and the alkoxycarbonyl group of  R$_{4}$ i, R$_{42 }$and R$_{43}$, and the substituent which these groups can  have in the formula (A) include, for example, an alkyl group,  a cycloalkyl group, an aryl group, an amino group, an amido  group, a ureido group, a urethane group, a hydroxyl group,  a carboxyl group, a halogen group, an alkoxy group, a  thioether group, an acyl group, an acyloxy group, an alkoxy- n represents an integer of 1 to 4.  Ar$_{4 }$ represents a (n+l)-valent aromatic ring group, and in  a case of being bonded to R$_{42 }$to form a ring, represents  a (n+2)-valent aromatic ring group.  carbonyl group, a cyano group, a nitro group, and the like  and the number of carbon atoms of the substituent is  preferably 10 or less.  Ar$_{4 }$ represents a (n+l)-valent aromatic ring group. A  divalent aromatic ring group in a case where n is 1 may have  a substituent, and for example, an arylene group having 6 to  18 carbon atoms such as a phenylene group, a tolylene  group, a naphthylene group, an anthracenylene group, or for  example, an aromatic ring group including a hetero ring such  as thiophene, furan, pyrrole, benzothiophene, benzofuran,  benzopyrrole, triazine, imidazole, benzoimidazole, triazole,  thiadiazole or thiazole is included as a preferred example.  Specific examples of the (n+ 1 )-valent aromatic ring group  in a case where n is an integer of 2 or more suitably can  include a group where arbitrary (n-1) hydrogen atoms are  removed from specific examples of the divalent aromatic  ring group described above.  The (n+l)-valent aromatic ring group may further have a  substituent.  Examples of the substituent which the alkyl group, the  cycloalkyl group, the alkoxycarbonyl, the alkylene group  and the (n+l)-valent aromatic ring group can have include  an alkyl group, an alkoxy group such as a methoxy group,  an ethoxy group, a hydroxyethoxy group, a propoxy group,  a hydroxypropoxy group and a butoxy group, and an aryl  group such as a phenyl group.  Examples of the alkyl group ofR$_{64 }$in-CONR$_{64}$- (R$_{64 }$ represents a hydrogen atom or an alkyl group) represented  by X$_{4 }$ include the same as an alkyl group ofR$_{61 }$to R$_{63 }$in the  general formula (Al) described above.  As X$_{4}$ ,  a single bond, --COO- and ----CONH- are  preferable and a single bond and --COO- are more pref› erable.  Examples of the alkylene group in L$_{4 }$ preferably include  an alkylene group having 1 to 8 carbon atoms such as a  methylene group, an ethylene group, a propylene group, a  butylene group, a hexylene group or an octylene group,  which may have a substituent.  As Ar$_{4}$ ,  an aromatic ring group having 6 to 18 carbon  atoms which may have a substituent is more preferable and  a benzene ring group, a naphthalene ring group and a  biphenylene ring group are particularly preferable.  A repeating unit (A) is preferably provided with a hydrox› ystyrene structure. That is, Ar4 is preferably a benzene ring  group.  Hereinafter, specific examples of the repeating unit (A)  represented by the general formula (A) are illustrated, but  the present invention is not limited thereto.  [Chem. 61]  ClOH  OH  OH  0  OH  OH  OH  OH 