Image forming color toner, color image forming method and color image forming apparatus

A method of forming a color image on a recording medium by means of an electrophotographic system which comprises the steps of forming an electrostatic latent image by image exposure, visualizing the electrostatic latent image by development, transferring the visualized image onto the recording medium and fixing the transferred image, wherein

• a developing agent used in the step of developing the electrostatic latent image contains a color toner comprising at least a binder resin and a colorant, which is used in an image forming method employing a photofixing system, said color toner further comprising at least one additive selected from the group consisting of:
• (1) light-absorbing fine composite particles comprising core particles and at least two coating layers having different refractive indexes laminated on the surface of the core particles;
• (2) an azulene compound represented by the following general formula (I):
• wherein R1 to R12 may be the same or different and each represents a hydrogen atom, or a substituted or unsubstituted, saturated or unsaturated, aliphatic hydrocarbon group, X represents an anion, and n represents a positive integer;
• (3) a cyanine compound represented by the following general formula (II):
• wherein R1 to R5 may be the same or different and each represents a hydrogen atom, a substituted or unsubstituted, saturated or unsaturated, aliphatic hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, or an aromatic hydrocarbon group having an aliphatic hydrocarbon side chain, and X represents an anion;
• (4) a quinoline compound represented by the following general formula (III):
• wherein RI represents a hydrogen atom, a halogen atom, or a monovalent substituent, RII and RIII may be the same or different and each represents a hydrogen atom, or a substituted or unsubstituted, saturated or unsaturated, aliphatic hydrocarbon group, M represents a transition metal atom, X represents an anion, and n represents a positive integer;
• (5) a quinoline compound represented by the following general formula (IV):
• wherein L represents a bonding group, RII and RIII may be the same or different and each represents a hydrogen atom, or a substituted or unsubstituted, saturated or unsaturated, aliphatic hydrocarbon group, M represents a transition metal atom, X represents an anion, and n represents a positive integer;
• (6) a polymethine compound represented by the following general formula (V):
• wherein R1 and R2 may be the same or different and each represents a hydrogen atom, a substituted or unsubstituted, saturated or unsaturated, aliphatic hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, or an aromatic hydrocarbon group having an aliphatic hydrocarbon side chain, and X represents an anion;
• (7) a benzene metal complex represented by the following general formula (VI):
• wherein R represents a monovalent substituent, A and B may be the same or different and each represents a sulfur atom, a selenium atom, or —NH, M represents a transition metal atom, and X represents a cation;
• and
• (8) a photothermal conversion ceramics;
• and
• photofixation is conducted at a light emission energy density ranging from 1.0 to 6.0 J/cm2 in the step of fixing the transferred image after transferring the image visualized by using the developing agent onto the recording medium.

An apparatus for forming a color image on a recording medium by means of an electrophotographic system, comprising an image exposing device for forming an electrostatic latent image, a developing device for visualizing the electrostatic latent image, an image transferring device for transferring the visualized image onto the recording medium, and an image fixing device for fixing the transferred image onto the recording medium, wherein

• the developing device is loaded with a developing agent comprising a color toner which comprises at least a binder resin and a colorant, said color toner further comprising at least one additive selected from the group consisting of:
• (1) light-absorbing fine composite particles comprising core particles and at least two coating layers having different refractive indexes laminated on the surface of the core particles;
• (2) an azulene compound represented by the following general formula (I):
• wherein R1 to R12 may be the same or different and each represents a hydrogen atom, or a substituted or unsubstituted, saturated or unsaturated, aliphatic hydrocarbon group, X represents an anion, and n represents a positive integer;
• (3) a cyanine compound represented by the following general formula (II):
• wherein R1 to R5 may be the same or different and each represents a hydrogen atom, a substituted or unsubstituted, saturated or unsaturated, aliphatic hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, or an aromatic hydrocarbon group having an aliphatic hydrocarbon side chain, and X represents an anion;
• (4) a quinoline compound represented by the following general formula (III):
• wherein RI represents a hydrogen atom, a halogen atom, or a monovalent substituent, RII and RIII may be the same or different and each represents a hydrogen atom, or a substituted or unsubstituted, saturated or unsaturated, aliphatic hydrocarbon group, M represents a transition metal atom, X represents an anion, and n represents a positive integer;
• (5) a quinoline compound represented by the following general formula (IV):
• wherein L represents a bonding group, RII and RIII may be the same or different and each represents a hydrogen atom, or a substituted or unsubstituted, saturated or unsaturated, aliphatic hydrocarbon group, M represents a transition metal atom, X represents an anion, and n represents a positive integer;
• (6) a polymethine compound represented by the following general formula (V):
• wherein R1 and R2 may be the same or different and each represents a hydrogen atom, a substituted or unsubstituted, saturated or unsaturated, aliphatic hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, or an aromatic hydrocarbon group having an aliphatic hydrocarbon side chain, and X represents an anion;
• (7) a benzene metal complex represented by the following general formula (VI):
• wherein R represents a monovalent substituent, A and B may be the same or different and each represents a sulfur atom, a selenium atom, or —NH, M represents a transition metal atom, and X represents a cation;
• and
• (8) a photothermal conversion ceramic;
• and
• the image fixing device is provided with a photofixing device having a light emission energy density ranging from 1.0 to 6.0 J/cm2.