19  US 9,323,153 B2  20  bomyl group, a tetracyclodecanyl group, a tetracyclododeca› nyl group, and an adamantyl group.  An embodiment where Rx 1  is a methyl group or an ethyl  group, and Rx 2  and Rx 3  are bonded to each other to form the  above-described cycloalkyl group is preferable.  The respective groups above may have a substituent, and  examples of the substituent include an alkyl group (having 1  to  4  carbon atoms), a halogen atom, a hydroxyl group, an  alkoxy group (having 1 to  4  carbon atoms), a carboxyl group  and an alkoxycarbonyl group (having 2 to 6 carbon atoms),  and the number of carbon atoms is preferably 8 or less.  In another embodiment, the resin (Ab) preferably contains  at least one kind of repeating units represented by the follow› ing general formulae (Al) and (A2)  [Chem. 9]  In the general formula (Al),  R 61 , R 62  and R 63  each independently represent a hydrogen  atom, an alkyl group, a cycloalkyl group, a halogen atom, a  cyano group or an alkoxycarbonyl group. However, R 62  may  be bonded to Ar 6  to form a ring, and in this case, R 62  repre› sents a single bond or an alkylene group.  X 6  represents a single bond, --COO-, or ----CONR 64 -.  R 64  represents a hydrogen atom or an alkyl group.  L 6  represents a single bond or an alkylene group.  Ar 6  represents a (n+ 1 )-valent aromatic ring group and in a  case of being bonded to R 62  to form a ring, represents a  (n+2)-valent aromatic ring group.  In a case of n= 1, Y  2  represents a group leaving by the action  of an acid and in a case of n2:2, Y/s each independently  represent a hydrogen atom or a group leaving by the action of  an acid. However, at least one of Y  2 ’ s represents a group  leaving by the action of an acid.  n represents an integer of 1 to 4.  The general formula (Al) will be described in more detail.  Examples of the alkyl group of R 61  to R 63  in the general  formula (Al) preferably include an alkyl group having 20 or  less carbon atoms such as a methyl group, an ethyl group, a  propyl group, an isopropyl group, an n-butyl group, a sec› butyl group, a hexyl group, a 2-ethylhexyl group, an octyl  group, a dodecyl group, which may have a substituent, and  more preferably include an alkyl group having 8 or less car› bon atoms.  Examples of the alkyl group included in analkoxycarbonyl  group are preferably the same as an alkyl group ofR 61  to R 63  described above.  A cycloalkyl group may be a monocyclic type or polycy› clic type and preferably include a monocyclic type cycloalkyl  group having  3  to 8 carbon atoms such as a cyclopropyl  group, a cyclopentyl group, a cyclohexyl group, which may  have a substituent.  Examples of the halogen atom include a fluorine atom, a  chlorine atom, a bromine atom and an iodine atom and a  fluorine atom is more preferable.  In a case where R 62  is bonded to Ar 6  to form a ring, R 62  represents a single bond or an alkylene group. Examples of  the alkylene group in this case 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 and an octylene group, which may have a  substituent. As a ring in which R 62  is bonded to Ar  6  to form, a  5-membered ring or a 6-membered ring is preferable.  Examples of the alkyl group in R 64  in ----CONR 64 - (R 64  represents a hydrogen atom or an alkyl group) represented by  X 6  include the same as an alkyl group ofR 61  to R 63 .  As X6, a single bond, -COO-and----CONH- are pref- erable and a single bond and --COO- are more preferable.  Examples of the alkylene group in L 6  preferably include a  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 and an octylene group,  which may have a substituent.  Ar 6  represents a (n+ 1 )-valent aromatic ring group. A diva› lent aromatic ring group may have a substituent in a case  where n is 1 and, for example, an arylene group having 6 to 18  carbon atoms such as a phenylene group, a tolylene group, a  naphthylene group or, for example, a divalent aromatic ring  group including a hetero ring such as thiophene, furan, pyr› role, benzothiophene, benzofuran, benzopyrrole, triazine,  imidazole, benzimidazole, triazole, thiadiazole or thiazole is  included as a preferred example.  Specific examples of the (n+l)-valent aromatic ring group  in a case where n is an integer of 2 or more suitably include a  group where arbitrary (n+l) hydrogen atoms are removed  from specific examples in divalent aromatic ring groups  described above.  The (n+l)-valent aromatic ring group may further have a  substituent.  Examples of the substituent which an alkyl group, a  cycloalkyl group, an alkoxycarbonyl, an alkylene group and  (n+l)-valent aromatic ring group can have described above,  include 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 atom,  an alkoxy group, a thioether group, an acyl group, an acyloxy  group, an alkoxycarbonyl group, a cyano group, a nitro group  or the like and the number of carbon atoms of the substituent  is preferably 10 or less.  n is preferably 1 or 2 and more preferably 1.  n Y2’ s each independently represent a hydrogen atom or a  group leaving by the action of an acid. However, at least one  of n represents a group leaving by the action of an acid.  Examples ofY2 of the group leaving by the action of an  acid include -C(R 36 )(R 37 )(R 38 ), ----C(=O)-O----C(R 36 )  (R37)(R3s),  -C(Ro1)(Ro2)(OR39),  -C(Ro1)(Ro2)----C  $^{(=O)-O----C(R}$36)(R 37 )(R 38 ), ----CH(R 36 )(Ar), or the like.  In the formulae, R 3 6  to R 3 8  each independently represent an  alkyl group, a cycloalkyl group, a monovalent aromatic ring  group, a group formed by a combination of an alky lene group  and a monovalent aromatic ring group, or an alkenyl group.  $^{R}$36 and R 37  may be bonded to each other to form a ring.  R 01  and R 02  each independently represent a hydrogen  atom, an alkyl group, a cycloalkyl group, a monovalent aro- (Al)  (A2) 