TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preparation (claimed): The triallylmethane derivative (I) is prepared by reacting naphthalene compound of formula (X) and cyclohexa-2,5-dien-1-yl(phenyl)methanol compound of formula (XI), oxidizing, and carrying out salt exchange reaction.    TECHNOLOGY FOCUS - POLYMERS - Preferred Composition: The polymer is a copolymer of monomer units derived from carboxyl group-containing monomer of formula: H2C=C(-R21)-COO-R22 (II), amide monomer of formula: H2C=C(-R21)-CON(-R31)-R32 (III), alkene monomer of formula: H2C=C(-R21)-R31 (IV) or cyclopent-4-ene-1,3-dione monomer of formula (V), and monomer unit derived from triallylmethane derivative (I).R21=H or methyl;R22=H, 1-18C alkyl, 1-10C hydroxyalkyl, 6-10C aryl, 7-13C arylalkyl, 2-9C alkoxyalkyl, 3-9C alkoxy alkoxyalkyl, 7-13C aryloxyalkyl, 5-7C morpholino alkyl, 3-9C trialkylsilyl, 6-10C alicyclic hydrocarbyl optionally having O, 3-9C dialkyl aminoalkyl, 1-18C fluoroalkyl or 1-6C N-alkylene phthalimide, -(R23-O)q-R24, R28-N+(-R25)(-R27)-R26 or -(CH2)l-O-C(=O)-R29-C(=O)-OH;R23=1-3C alkylene optionally substituted by hydroxy;R24=phenyl optionally substituted by hydroxy or 1-3C alkyl;q=1-3;R25,R26=1-3C alkyl;R28=1-3C alkylene;l=1-6;R29=phenylenyl or cyclohexylenyl;R31=H or 1-3C alkyl;R32=H, 1-3C alkyl, 3-9C dialkyl aminoalkyl or 1-6C hydroxyalkyl;R31+R32+N=morpholino;R33=phenyl or pyrrolidino;R35=N or O;j=0 (when R35 is O) or 1 (when R35 is N);andR34=H, 1-20C alkyl, 1-10C hydroxyalkyl, 1-10C haloalkyl, 6-10C alkylcycloalkyl, 6-7C halocycloalkyl, 6-10C aryl, 6-10C aryl comprising 1-6C alkyl as substituent, or 6-10C haloaryl. Preferred Definitions:    electron-withdrawing substituent=fluoro;and    An-=tetrakis(perfluoro phenyl)borate anion.    EXAMPLE - To 1 L round bottom flask provided with stirring apparatus, 11 g 2-(((4-((4-(dimethylamino)-3-methylphenyl)(4-(dimethylamino)cyclohexa-2,5-dien-1-ylidene)methyl)naphthalen-1-yl)carbamoyl)amino)ethyl 2-methylprop-2-enoate, 330 ml toluene, 330 ml dichloromethane, 220 ml 1 mol/L hydrochloric acid and 4.9 g chloranil were added, and stirred at room temperature for 4 hours. Then, 14.9 g lithium salt of tetrakis (pentafluorophenyl) boron (IV) was added, and stirred at room temperature for 12 hours. The water layer was removed by liquid separation, organic layer was washed in 3% potassium carbonate aqueous solution, and dried using sodium sulfate. The resultant product was concentrated under reduced pressure, to obtain 22.3 g 2-(((4-((4-(dimethylamino)-3-methylphenyl)(4-(dimethylimino)cyclohexa-2,5-dien-1-ylidene)methyl)naphthalen-1-yl)carbamoyl)amino)ethyl 2-methylprop-2-enoate chloride with yield of 91% as dark blue solid.