US 10,921,710 B2  72  71  (B-3)  -continued  0  The PAG as component (B) may further contain a com› pound having the following formula (B-3).  Herein A 3  and A  4  are each independently hydrogen or  trifluoromethyl, excluding that both A 3  and A  4  are hydrogen  at the same time. R$^{25 }$is a C$_{1 }$-C$_{35 }$straight, branched or cyclic  monovalent hydrocarbon group which may contain oxygen,  a nitrogen-containing heterocyclic group, or a group of the  formula (i).  MB+  is an onium cation.  Examples of the monovalent hydrocarbon group and  nitrogen-containing heterocyclic group represented by R 25  are as exemplified above for R 21 . Examples of the onium  cation  MB+  are as exemplified above for  MA+.  Exemplary structures of the anion moiety in the PAG  having formula (B-3) are shown below, but not limited  thereto. 