Color image forming method using flattened toner

A color image forming method for forming a color toner image, comprising the steps of:

• forming toner images of three color toners of yellow, magenta, and cyan and a black toner;
• and
• superposing the toner images, thereby forming the color toner image,
• wherein each of said color toners is a flattened toner composed of particles each having an equivalent circle diameter d of 5 to 10 (μm) when viewed from a direction to make a projection area maximum, a thickness t of 1 to 4 (μm), and a flattening ratio d/t of 2 to 8 represented by a ratio of said equivalent circle diameter d to said thickness t, and
• wherein the flattening ratio d/t of the particles of each of said three color toners is larger than a flattening ratio dk/tk of the particles of said black toner, where dk and tk represent an equivalent circle diameter and a thickness, respectively, of the particles of said black toner.