| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide an image forming device, whose running cost is reduced and which is environmental friendly by decreasing the consumption of toner after satisfying a user's requirement on image quality, saving the toner excessively stuck to an electrostatic latent image on a photoreceptor drum, improving transfer efficiency and decreasing the amount of waste toner. SOLUTION: In this image forming device, a developer contains toner particles whose particle diameter is >=3μm and whose circularity (a) obtained by expression (1) is >=0.90, and >=90% in number and moreover the toner particles whose circularity (a) is >=0.98 and <30% in number in toner particles, and image processing including binarization is performed, and developing contrast is set to <=180 V. (1) circularity (a)=L0/L (L0: the peripheral length of a circle having the same projected area as particle image, and L: the peripheral length of the projected image of the particles).</p> |
