INDOLENINE COMPOUND, NEAR INFRARED ABSORBER, AND TONER CONTAINING THE SAME

摘要

A novel indolenine compound which has a high molar extinction coefficient (weight extinction coefficient) and shows considerably reduced absorption in the visible light region; an infrared absorber; and a toner containing the absorber, specifically a toner for noncontact thermal fixing, especially such as the flash fixing type, which has satisfactory fixability, is reduced in influence on the color tones of color toners, and has a high molar extinction coefficient. The indolenine compound is represented by the following general formula (1). Also provided are: a near infrared absorber comprising the indolenine compound; and a toner for copiers of the noncontact thermal fixing type, which contains the indolenine compound. <CHEM> In the formula (1), R represents a group represented by the following general formula (2). -((CH2)bO)a(CH2)cOR1 (wherein a is 1 or 0, b and c each independently is 1 or 2, and R1 represents C4 or lower alkyl) ; and X<-> represents an ion for charge neutralization.