An azo dye represented by formula (1):
wherein, R11 represents a monovalent substituent, R12 represents a hydrogen atom or a monovalent substituent, Ar1 represents a specific heterocyclic group such as a group such as a group shown below, and X represents atoms necessary to form a ring;
wherein, in the heterocyclic group, R61 to R63 each independently represents a hydrogen atom or a substituent.
由式 (1) 表示的偶氮
染料:
其中,R11 代表一价取代基,R12 代表氢原子或一价取代基,Ar1 代表特定的杂环基团,例如下图所示的基团,X 代表形成环所需的原子;
其中,在杂环基团中,R61 至 R63 各自独立地代表氢原子或取代基。