Aug. 4, 2016  35  US 2016/0223905 Al  [0300]  The organic group not having a aromatic ring as  R$_{201 }$to R$_{203 }$has generally 1 to 30 carbon atoms, and prefer› ably 1 to 20 carbon atoms.  [0301]  R$_{201 }$ to R$_{203 }$ are each independently preferably an  alkyl group, a cycloalkyl group, an ally! group, or a vinyl  group, more preferably a linear or branched 2-oxoalkyl  group, a 2-oxocycloalkyl group, or an alkoxycarbonylmethyl  group, and particularly preferably a linear or branched  2-oxoalkyl group.  [0302]  Preferred examples of the alkyl group and the  cycloalkyl group ofR$_{201 }$to R$_{203 }$include a linear or branched  alkyl group having 1 to 10 carbon atoms (for example, a  methyl group, an ethyl group, a propyl group, a butyl group,  and a penty I group), and a cycloalky I group having 3 to 10  carbon atoms (a cyclopentyl group, a cyclohexyl group, and a  norbornyl group).  [0303]  R$_{201 }$to R$_{203 }$may be further substituted with a halo› gen atom, an alkoxy group (for example, having 1 to 5 carbon  atoms), a hydroxyl group, a cyano group, and a nitro group.  [0304]  Next, the compound (ZI-3) will be described.  [  03 05]  The compound (ZI-3) is a compound represented by  the following General Formula (ZI-3), having a phenacylsul› fonium salt structure.  (ZI-3)  [0306]  In General Formula (ZI-3),  [0307]  R$_{1}$c to R 5 c each independently represent a hydrogen  atom, an alkyl group, a cycloalkyl group, an aryl group, an  alkoxy group, an aryloxy group, an alkoxycarbonyl group, an  alkylcarbonyloxy group, a cycloalkylcarbonyloxy group, a  halogen atom, a hydroxyl group, a nitro group, an alkylthio  group, or an arylthio group,  [0308]  R$_{6}$ c and R 7 c each independently represent a hydro› gen atom, an alkyl group, a cycloalkyl group, a halogen atom,  a cyano group, or an aryl group, and  [0309]  Rx  and  RY  each independently represent an alkyl  group, a cycloalkyl group, a 2-oxoalkyl group, a 2-oxocy› cloalkyl group, an alkoxycarbonylalkyl group, an ally! group,  or a vinyl group.  [0310]  Any two or more ofR$_{1}$ c to R 5 c, R 5 c and R 6 c, R 6 c and  R$_{7}$c, R 5 c and  Rx,  or  Rx  and  RY  may be respectively bonded to  each other to form a ring structure, and this ring structure may  contain an oxygen atom, a sulfur atom, a ketone group, an  ester bond, or an amide bond.  [0311]  Examples of the ring structure include an aromatic  or non-aromatic hydrocarbon ring, an aromatic or non-aro› matic heterocycle, and a polycyclic fused ring formed by  combination of two or more of these rings. Examples of the  ring structure include 3- to 10-membered rings, with 4- to  8-membered rings being preferable, and 5- or 6-membered  rings being more preferable.  [0312]  Examples of the group formed by combination of  any two or more ofR$_{1}$c to R 5 c, a pair ofR 6 c and R 7 c, or a pair  of  Rx  and  RY  include a butylene group, and a pentylene group.  [0313]  The group formed by combination of a pair of R$_{5}$ c  and R$_{6}$c, or a pair ofR 5 c and  Rx  is preferably a single bond or  an alkylene group, and examples of the alkylene group  include a methylene group and an ethylene group.  [0314]  zc- represents a non-nucleophilic anion, and  examples thereof include the same ones as the non-nucleo› philic anions of  z- in General Formula  (ZI).  [0315]  Specific examples of the alkoxy group in the alkoxy› carbonyl group as R$_{1}$c to R 5 c are the same as the specific  examples of the alkoxy group as R$_{1}$ c to R 5 c above.  [0316]  Specific examples of the alkyl group in the alkylcar› bonyloxy group and the alkylthio group as R$_{1}$ c to R 5 c are the  same as the specific examples of the alkyl group as R$_{1}$c to R 5 c  above.  [0317]  Specific examples of the cycloalkyl group in the  cycloalkylcarbonyloxy group as R$_{1}$ c to R 5 c are the same as the  specific examples of the cycloalkyl group as R$_{1}$ c to R 5 c above.  [0318]  Specific examples of the aryl group in the aryloxy  group and the arylthio group as R$_{1}$c to R 5 c are the same as the  specific examples of the aryl group as R$_{1 }$c to Rx above.  [0319]  Examples of the cation in the compound (ZI-2) or  (ZI-3) in the present invention including the cations described  after paragraph "0036" in the specification of US2012/  0076996Al.  [0320]  Next, the compound (ZI-4) will be described.  [0321]  The compound (ZI-4) is represented by the follow› ing General Formula (ZI-4).  (Zl-4)  [0322]  In General Formula (ZI-4),  [0323]  R$_{13 }$represents a hydrogen atom, a fluorine atom, a  hydroxyl group, an alkyl group, a cycloalkyl group, an alkoxy  group, an alkoxycarbonyl group, or a group having a  cycloalkyl group, and these groups may have a substituent, in  the case where R  14 ’ s are present in plural numbers, they each  independently represent a hydroxyl group, an alkyl group, a  cycloalkyl group, an alkoxy group, an alkoxycarbonyl group,  an alky lcarbony I group, an alky lsulfony I group, a cycloalkyl› sulfony l group, or a group having a cycloalkyl group, and  these groups may have a substituent,  [0324]  R$_{15}$’s each independently represent an alkyl group,  a cycloalkyl group, or a naphthyl group, these groups may  have a substituent, two R$_{15}$’s may be bonded to each other to  form a ring, and when two R$_{15}$’s are bonded to each other to  form a ring, the ring skeleton may contain a hetero atom such  as an oxygen atom and a nitrogen atom; and in an aspect, two  R$_{15 }$’s are alkylene groups, and are preferably bonded to each  other to form a ring structure,  [0325]  I represents an integer ofO to 2,  [0326]  r represents an integer of Oto 8, and  [0327]  z- represents  a  non-nucleophilic  anion,  and  examples thereof include the same ones as the nucleophilic  anions of z- in General Formula  (ZI).  0  Rx  I  s+  ’-R  z- y  C 