Image forming material and ammonium compound

An ammonium compound represented by the following general formula (1-N):

• General Formula (1-N)
• 277
• wherein RN1 and RN2 independently represent a substituent selected from an alkyl group, an alkenyl group, an alkynyl group, an aryl group, an amino group, an alkoxy group, an aryloxy group, an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an acyloxy group, an acylamino group, an alkoxycarbonylamino group, an aryloxycarbonylamino group, a sulfonylamino group, a sulfamoyl group, a carbamoyl group, an alkylthio group, an arylthio group, a sulfonyl group, a hydroxyl group, a mercapto group, a halogen atom, a cyano group, a sulfo group, a carboxyl group and a nitro group, m and n independently denote an integer from 0 to 5, provided that when plural RN1 and RN2 are respectively present, plural RN1s and RN2s may be independently the same or different or may independently bond to each other to form a ring, Y represents —CH2—, —O— or —S— and X− represents an anion corresponding to a conjugate base of an organic acid or an inorganic acid.