Disclosed is a compound containing a specific structure having an azomethine part, the compound being reversibly fluidized and non-fluidized by being irradiated with light.

Provided is a compound which is fluidized by light irradiation and is less colored. The compound is a compound represented by the following general formula (1), which is fluidized by light irradiation:

R.sub.1—CH═N—R.sub.2  General Formula (1)

wherein R.sub.1 is a substituted or unsubstituted cyclic hydrocarbon group or a substituted or unsubstituted heterocyclic group; and R.sub.2 is a substituted or unsubstituted heterocyclic group containing a nitrogen atom bonded to the nitrogen atom in the general formula (1).

Provided is a compound that is fluidized by light irradiation and reversibly non-fluidized, is not significantly colored, and improves fixability and exhibits excellent image stability and color reproducibility when used for a toner.

Provided is a compound represented by the following general formula (1), which is fluidized by light irradiation and reversibly non-fluidized:

##STR00001##

wherein

Z.sub.1 and Z.sub.2 are CH or N, and Z.sub.1≠Z.sub.2;

R.sub.1 is an aromatic hydrocarbon group having a substituent R.sub.a selected from the group consisting of an alkyl group, an alkoxy group and a halogen atom at each of two ortho positions with respect to Z.sub.1; and

R.sub.2 is a substituted or unsubstituted aromatic heterocyclic group.

An object of the present invention is to provide a photoresponsive polymer that sufficiently secures photoresponsiveness to be fluidized by light irradiation and reversibly non-fluidized, improves fixability, and further has good color reproducibility.

Provided is a photoresponsive polymer containing a structural unit derived from a specific azomethine derivative, the photoresponsive polymer being fluidized by light irradiation and reversibly non-fluidized.

Provided is a compound that is fluidized by light irradiation and reversibly non-fluidized, and is not significantly colored.

Provided is a photoresponsive compound represented by the following general formula (1), the photoresponsive compound being fluidized by light irradiation and reversibly non-fluidized:

R.sub.1—Z.sub.1═Z.sub.2—R.sub.2  General formula (1) wherein Z.sub.1 and Z.sub.2 are N or CH, while Z.sub.1≠Z.sub.2, R.sub.1 contains an aromatic hydrocarbon structure, R.sub.2 contains an aromatic heterocyclic structure, and a hydrogen atom is bonded to at least one carbon atom bonded adjacent to a carbon atom in the aromatic heterocyclic structure bonded to the Z.sub.2.

Provided is a compound that is fluidized by light irradiation and reversibly non-fluidized, and is not significantly colored. Provided is a photoresponsive compound represented by the following general formula (1), the photoresponsive compound being fluidized by light irradiation and reversibly non-fluidized:
R.sub.1—Z.sub.1═Z.sub.2—R.sub.2  General formula (1) wherein Z.sub.1 and Z.sub.2 are N or CH, while Z.sub.1≠Z.sub.2, R.sub.1 contains an aromatic hydrocarbon structure, R.sub.2 contains an aromatic heterocyclic structure, and a hydrogen atom is bonded to at least one carbon atom bonded adjacent to a carbon atom in the aromatic heterocyclic structure bonded to the Z.sub.2.

A compound that is fluidized by light irradiation and reversibly non-fluidized and is represented by the following general formula (1):

##STR00001##

In the general formula (1), Ar.sub.1 and Ar.sub.2 each independently represent an aromatic hydrocarbon group optionally having a substituent or an aromatic heterocyclic group optionally having a substituent, and Y, Z.sub.1, and Z.sub.2 each independently represent a hydrogen atom or a lower alkyl group.

Provided is a toner including a binder resin and a colorant, wherein the colorant includes Solvent Red 49, and an acid value of the toner is 9.0 mgKOH/g or greater but 30.0 mgKOH/g or less.

Provided is a toner including a binder resin and a colorant, wherein the colorant includes Solvent Red 49, and an acid value of the toner is 9.0 mgKOH/g or greater but 30.0 mgKOH/g or less.

Disclosed is a compound containing a specific structure having an azomethine part, the compound being reversibly fluidized and non-fluidized by being irradiated with light.