Patent ID: 8460845

Claim:
A cyan toner comprising toner particles each of which has a toner base particle (A) and a surface layer (B) formed on the toner base particle (A), wherein: the toner base particle (A) comprises at least a resin (a), a cyan colorant and a wax, the resin (a) having a polyester as a main component; the surface layer (B) comprises a resin (b) as a main component, the resin (b) being a polyurethane including a carboxylic acid group, a sulfonic acid group, a carboxylate, or a sulfanate in a side chain thereof; the cyan toner satisfies the following formulas (1) and (2) in DSC measurement: 40.0 ≦Tg (0.5)≦60.0 (1) 2.0 ≦Tg (4.0)− Tg (0.5)≦10.0 (2) where Tg(0.5) is a glass transition temperature (° C.) obtained at a rate of temperature increase of 0.5° C./min, and Tg(4.0) is a glass transition temperature (° C.) obtained at a rate of temperature increase of 4.0° C./min; when the concentration of the cyan toner in an ethyl acetate dispersion is Cc 1 (mg/ml), and the light absorbance at a wavelength of 712 nm of the dispersion is A(ethyl acetate)712, a relationship between Cc 1 and A(ethyl acetate)712 satisfies the following formula (3): A (ethyl acetate)712/ Cc 1 <0.15 (3); and when the concentration of the cyan toner in a chloroform solution is Cc 2 (mg/ml), and the light absorbance at a wavelength of 712 nm of the solution is A(chloroform)712, a relationship between Cc 2 and A(chloroform)712 satisfies the following formula (4): 2.00 <A (chloroform)712 /Cc 2 <8.15 (4).