US 2019/0196326 Al  4  Jun.27,2019  0  [0085]  One of the specific examples of the acid repre› sented by Formula (I) is provided below.  [0077]  Examples of the monovalent organic group includ› ing a fluorine atom represented by Rf include a linear or  [0076]  Among these, the alkyl group having  2  to  20  carbon atoms as the organic group having 2 or more carbon  atoms which is represented by R 2  is preferably an alkyl  group having 3 to 10 carbon atoms, and more preferably an  alkyl group represented by *----CH$_{2}$-X. X represents a  cycloalkyl group having 3 to 9 carbon atoms or a linear alkyl  group having 2 to 9 carbon atoms and preferably represents  a cycloalkyl group having 3 to 9 carbon atoms. * represents  a bonding position.  [0075]  Among the aforementioned groups, the organic  group having 2 or more carbon atoms which is represented  by R 2  is preferably a hydrocarbon group having  2  to  20  carbon atoms which may include a hetero atom, more  preferably an alkyl group having  2  to  20  carbon atoms or an  alkyl group having  2  to  20  carbon atoms in total in which  -CH$_{2}$ - is substituted with any one selected from the group  consisting of -0-, --CO-, ---OCO-, and --COO-,  even more preferably an alkyl group having  2  to  20  carbon  atoms, an alkoxyalkyl group having  2  to  20  carbon atoms, an  acylalkyl group having  2  to  20  carbon atoms, or an alky› loxycarbonylalkyl group having 3 to  20  carbon atoms, and  particularly preferably an alkyl group having 1 to  20  carbon  atoms, an alkoxyalkyl group having 2 to 10 carbon atoms, an  acylalkyl group having 2 to 10 carbon atoms, or an alky› loxycarbonylalkyl group having 3 to 10 carbon atoms.  [0084]  Examples of the suitable aspect of the acid repre› sented by Formula  (I) include an aspect in which R 1  s a  linear or branched alkyl group, R 2  may be a hydrocarbon  group having  2  to  20  carbon atoms which may include a  hetero atom, Rf is a fluorine atom, and n is 1. Among these,  an aspect in which R 1  is a linear or branched alkyl group  having 1 to 5 carbon atoms, R $^{2 }$is an alkyl group having 3 to  10 carbon atoms, Rf is a fluorine atom, and n is 1 is  preferable.  [0074]  The alkyloxycarbonylalkyl group having 3 to  20  carbon atoms is preferably an alkyloxycarbonylalkyl group  having 3 to 10 carbon atoms, and examples thereof include  a methoxycarbonylmethyl group.  [0073]  The acylalkyl group having  2  to  20  carbon atoms is  preferably an acylalkyl group having 2 to 10 carbon atoms,  and examples thereof include an acetylmethyl group and an  acetylethyl group.  [0083]  n represents  O  or 1. In view of acidity of the acid  represented by Formula (I), it is preferable that n represents  1.  [0082]  In a case where X represents ----CON(Rb)-,  Rb  and R  1  may be linked to each other to form a ring.  [0081]  In view of acidity of the acid represented by  Formula (I), X is preferably -CO- or -COO-.  [0072]  The alkoxyalkyl group having  2  to  20  carbon atoms  is preferably an alkoxyalkyl group having 2 to 10 carbon  atoms, and examples thereof include a methoxyethyl group.  [0080]  Rb  represents a hydrogen atom or a hydrocarbon  group (preferably an alkyl group having 1 to 5 carbon atoms)  having 1 to  20  carbon atoms.  [0071]  Examples of the hydrocarbon group having  2  to  20  carbon atoms in total, which has any one selected from the  group consisting of -0-, -S-, --CO-, -SO$_{2}$ -,  and  -NRa- or a group obtained by combining a plurality of  these include a group in which ----CH$_{2}$ - in the alkyl group  having  2  to  20  carbon atoms is substituted with any one  selected from the group consisting of -0-, -S-,  -CO-, -SO$_{2}$ -,  and  -NRa- or a group obtained by  combining a plurality of these. Among these, a group in  which -CH$_{2}$ - in the alkyl group having  2  to  20  carbon  atoms is substituted with any one selected from the group  consisting of  ---0-, --CO-, -OCO-, and -COO- is  preferable, and an alkoxyalkyl group having  2  to  20  carbon  atoms, an acylalkyl group having  2  to  20  carbon atoms, or  an alkyloxycarbonylalkyl group having 3 to  20  carbon atoms  is more preferable.  [0079]  The divalent electron withdrawing group repre› sented by X is not particularly limited, but examples thereof  include  -CO-,  -CON(Rb)-,  --COO-,  ----C(  NRb)-,  -SO-, and -SO$_{2}$ -.  In the specific  examples exemplified as the divalent electron withdrawing  group, a bonding position thereof is not particularly limited.  In Formula  (I), in a case where X is --COO-, a bond  formed by X and R  1  may be -OCO-R  1  or may be  ----COO-R  1 .  That is, the carbonyl carbon of ---OCO- may  be bonded to R $^{1 }$and the ether oxygen of --COO- may be  bonded to R  1 .  [0078]  Rf is preferably a fluorine atom or a perfluoroalkyl  group having 1 to 4 carbon atoms, more preferably a fluorine  atom or CF $_{3}$ ,  and even more preferably a fluorine atom.  branched alkyl group having 1 to 10 carbon atoms in which  a portion or all of hydrogen atoms are substituted with a  fluorine atom or a fluoroalkyl group. Specific examples  thereof include CF$_{3}$, C$_{2}$F$_{5}$ , C$_{3}$F$_{7}$ , C$_{4}$ F$_{9}$, C$_{5}$F  w  C$_{6}$F $_{13}$, C$_{7}$F $_{15}$,  C$_{8}$F$_{17}$, CH$_{2}$CF$_{3}$ , CH$_{2}$CH$_{2}$CF$_{3}$, CH$_{2}$C$_{2}$F$_{5}$, CH$_{2}$CH$_{2}$C$_{2}$F$_{5}$ ,  CH$_{2}$C$_{3}$F$_{7}$ ,  CH$_{2}$CH$_{2}$C$_{3}$F$_{7}$ ,  CH$_{2}$C$_{4}$ F$_{9}$ ,  and CH$_{2}$CH$_{2}$C$_{4}$F$_{9}$ .  a propyl group, a butyl group, a pentyl group, a hexyl group,  a heptyl group, an octyl group, a nonyl group, a decyl group,  a dodecyl group, a tridecyl group, a tetradecyl group, a  pentadecyl group, a hexadecyl group, a heptadecyl group, an  octadecyl group, a nonadecyl group, an eicosyl group, a  cyclopropyl group, a cyclobutyl group, a cyclopentyl group,  a cyclohexyl group, a norbomyl group, and an adamantyl  group.  [0070]  Examples of the aromatic hydrocarbon group hav› ing 6 to  20  carbon atoms include a phenyl group. 