An electrostatic image developing toner set includes a brilliant toner having brilliant toner particles that include a binder resin and a brilliant pigment, and a color toner having color toner particles that include a binder resin and a colorant other than the brilliant pigment. The binder resin included in the brilliant toner particles and the binder resin included in the color toner particles are incompatible with each other.

An image forming apparatus includes a developing unit, a transferring unit, and a fixing unit. The developing unit performs an attachment process in which the developing unit attaches a luminescent toner to a latent image that is formed on a basis of image data. The transferring unit performs a transfer process in which the transferring unit transfers, onto a medium, the luminescent toner attached to the latent image. The fixing unit performs a fixing process in which the fixing unit fixes, to the medium, the luminescent toner transferred onto the medium. The attachment process performed by the developing unit and the transfer process performed by the transferring unit are each performed plural times for the medium, on the basis of the image data.

A resin particle set includes a fluorescent color resin particle containing a fluorescent coloring agent; and a colored resin particle containing a colored coloring agent, wherein a volume average particle diameter of the fluorescent color resin particles is larger than a volume average particle diameter of the colored resin particles, and an average circularity of the fluorescent color resin particles is 0.93 or more.

A resin particle set includes a fluorescent color resin particle containing a fluorescent coloring agent; and a colored resin particle containing a colored coloring agent, wherein a volume average particle diameter of the fluorescent color resin particles is larger than a volume average particle diameter of the colored resin particles, and an average circularity of the fluorescent color resin particles is 0.93 or more.

A decolorizable toner allows for easy distinguishing between a sheet which can be reused and a sheet which is hardly able to be reused from each other. The decolorizable toner includes a color developable compound, a color developing agent, a decolorizing agent, a magnetic material, and a binder resin. The color developable compound is a precursor compound of a dye. The color developing agent is an electron accepting compound which donates a proton to the color developable compound. The decolorizing agent is a compound which inhibits a coloring reaction between the color developable compound and the color developing agent.

A decolorizable toner allows for easy distinguishing between a sheet which can be reused and a sheet which is hardly able to be reused from each other. The decolorizable toner includes a color developable compound, a color developing agent, a decolorizing agent, a magnetic material, and a binder resin. The color developable compound is a precursor compound of a dye. The color developing agent is an electron accepting compound which donates a proton to the color developable compound. The decolorizing agent is a compound which inhibits a coloring reaction between the color developable compound and the color developing agent.

A reversibly allochroic toner contains a binder resin and a colorant. The colorant reversibly switches between first and second color states in response to temperature changes. The colorant exhibits a hysteresis in a temperature-color state curve thereof in which the following relationships are satisfied.
Tr<T.sub.L2<T.sub.L1<T.sub.H1<T.sub.H2<Tg
T.sub.H250 C.
20 C.Tr30 C. where, T.sub.H1 is a temperature at which the colorant starts to change from the first color state to the second color state, T.sub.H2 is a temperature at which the colorant completely changes to the second color state, T.sub.L1 is a temperature at which the colorant starts to change from the second color state to the first color state, T.sub.L2 is a temperature at which the colorant completely changes to the first color state, and Tg is a glass transition temperature of the binder resin.

A decolorizable toner allows for easy distinguishing between a sheet which can be reused and a sheet which is hardly able to be reused from each other. The decolorizable toner includes a color developable compound, a color developing agent, a decolorizing agent, a magnetic material, and a binder resin. The color developable compound is a precursor compound of a dye. The color developing agent is an electron accepting compound which donates a proton to the color developable compound. The decolorizing agent is a compound which inhibits a coloring reaction between the color developable compound and the color developing agent.

A decolorizable toner allows for easy distinguishing between a sheet which can be reused and a sheet which is hardly able to be reused from each other. The decolorizable toner includes a color developable compound, a color developing agent, a decolorizing agent, a magnetic material, and a binder resin. The color developable compound is a precursor compound of a dye. The color developing agent is an electron accepting compound which donates a proton to the color developable compound. The decolorizing agent is a compound which inhibits a coloring reaction between the color developable compound and the color developing agent.

A decolorizable toner allows for easy distinguishing between a sheet which can be reused and a sheet which is hardly able to be reused from each other. The decolorizable toner includes a color developable compound, a color developing agent, a decolorizing agent, a magnetic material, and a binder resin. The color developable compound is a precursor compound of a dye. The color developing agent is an electron accepting compound which donates a proton to the color developable compound. The decolorizing agent is a compound which inhibits a coloring reaction between the color developable compound and the color developing agent.