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[0446] -Cation Moiety 

[0447] In formula (dl-1), Mm+ represents an organic cat› ion having a valency of m. As the organic cation for Mm+, for example, the same cation moieties as those represented by the aforementioned formulae (ca-1) to (ca-5) are prefer› able, cation moieties represented by the aforementioned general formulae ( ca-1) is preferable, and cation moieties represented by the aforementioned formulae (ca-1-1) to ( ca-1-72) are still more preferable. 

[0448] As the component (d 1-1), one kind of compound may be used, or two or more kinds of compounds may be used in combination. 

[0449] { Component ( dl-2)} 

[0450] -Anion Moiety 

[0451] In formula (dl-2), Rd $^{2 }$represents a cyclic group which may have a substituent, a chain-like alkyl group which may have a substituent or a chain-like alkenyl group which may have a substituent, and is the same groups as those defined above for R$^{101 }$in the aforementioned formula (b-1 ). 

[0452] provided that, the carbon atom adjacent to the sulfur atom within Rd $^{2 }$group has no fluorine atom bonded 

thereto (i.e., the carbon atom adjacent to the sulfur atom within Rd $^{2 }$group does not substituted with a fluorine atom). As a result, the anion of the component ( dl-2) becomes an appropriately weak acid anion, thereby improving the quenching ability of the component (D). 

[0453] As Rd 2 , a chain-like alkyl group which may have a substituent or an aliphatic cyclic group which may have a substituent is preferable. The chain-like alkyl group prefer› ably has 1 to 10 carbon atoms, and more preferably 3 to 10 carbon atoms. As the aliphatic cyclic group, a group in which one or more hydrogen atoms have been removed from adamantane, norbomane, isobomane, tricyclodecane, tetra› cyclododecane or camphor (which may have a substituent) is more preferable. 

[0454] The hydrocarbon group for Rd $^{2 }$may have a sub› stituent. As the substituent, the same groups as those described above for substituting the hydrocarbon group ( e.g., aromatic hydrocarbon group, aliphatic cyclic group, chain-like alkyl group) for Rd$^{1 }$in the formula (dl-1) can be mentioned. 

[0455] Specific examples of preferable anion moieties for the component (dl-2) are shown below. 

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