TECHNOLOGY FOCUS - POLYMERS - Preferred Components: The first and the second ionomers comprise sulfinic acid groups of formula (-SO2X), phosphonic acid groups or carbonyl groups of formula (-COX). The first ionomer exhibits an equivalent weight of less than 750. The second ionomer exhibits an equivalent weight of greater than 850. The first and the second ionomers comprise: a perfluorosulfonic acid polymer; a polymer exhibiting perfluorocyclobutyl groups comprising perfluorocyclobutane-1,2-diyl- or perfluorocyclobutane-1,3-diyl groups; a protogenic groups-containing polymer segment of formula (E11-P1-Q1-P2) (I), ((E1(Z1)d)-P1-Q1-P2) (II), (E2-P3-Q2-P4) (III), (E11(R8(Z1)d1)-P11-Q1-P12) (IV), (E12-P13-Q2-P14) (V), (E1(SO2X)d-P1-Q1-P2) (VI) and (E2-P3-Q2-P4) (VII).X = -OH, halo, ester or -NH-S(=O)2-R4;E11 = moiety having protogenic group;P1, P2 = -O-, -S-, -SO-, -CO-, -SO2-, -NH-, -NR2- or -R3-, where P1 and P2 are optionally present;R2 = 1-25C alkyl, 1-25C aryl or 1-25C arylene;R3, R8 = 1-25C alkylene, 1-25C perfluoro-alkylene, perfluoroalkylether, alkylether or 1-25C arylene;R4 = CF3, 1-25C alkyl, 1-25C perfluoro-alkylene, 1-25C aryl or E1;Q1, Q2 = fluorinated cyclobutyl;Z1 = protogenic group e.g. -SO2X, -PO3H2 or COX, where Z1 is optionally present;E1 = aromatic group;E2, E11, E12 = aromatic and/or aliphatic group (both unsulfonated);d = number of Z1 bonded to E1;P3, P4 = -O-, -S-, -SO-, -CO-, -SO2-, -NH-, -NR2- or -R3-, where P3 and P4 are optionally present;d1 = number of Z1 bonded to R8; andP11-P14 = -O-, -S-, -SO-, -CO-, -SO2-, -NH-, -NR2- or -R3-, where P11-P14 are optionally present. EXAMPLE - 36.66 g n-Propanol, 9.29 g deionized water, 1.19 g ionomer with low equivalent weight, and 10.27 g Nafion (RTM: Sulfonated tetrafluoroethylene based fluoropolymer-copolymer) were mixed for 30 minutes. Then 2.6 g platinum alloy catalyst and 240 g spherical zirconium oxide grinding media were added to the mixture. Then the mixture was milled for 24 hours to obtain the ink composition.