Developing device of a non-magnetic one-component development type capable of suppressing toner melt adhesion to a regulation blade and image forming apparatus including the same

A developing device that supplies a toner to an image carrying member on which an electrostatic latent image has been formed, the developing device comprising:

• a development container for containing a non-magnetic one-component developer composed only of the toner;
• a developer carrying member including:
• a rotary shaft;
• and
• a roller portion that is stacked on an outer circumferential surface of the rotary shaft and is brought into pressure contact at a prescribed pressing force with the image carrying member,
• on an outer circumferential surface of the roller portion, the toner being carried to form a toner layer;
• and
• a regulation blade that contacts the outer circumferential surface of the roller portion so as to regulate a thickness of the toner layer formed on the outer circumferential surface of the roller portion,
• wherein
• the developer carrying member is manufactured by a polishing method in which the roller portion being rotated about the rotary shaft is contacted by a grindstone so as to be polished,
• when a ten-point average roughness in a circumferential direction and a ten-point average roughness in an axial direction of the roller portion are indicated as Rz1 and Rz2, respectively, Rz1/Rz2≤1.5 is satisfied, and
• a contact linear pressure of the regulation blade with respect to the roller portion is not less than 15 [N/m] and not more than 40 [N/m], wherein
• a contact area ratio of the developer carrying member is defined as a ratio of an area of actual contact between the outer circumferential surface of the roller portion and a plane of a pressing member to an area of a nip between the outer circumferential surface and the plane when made to contact the outer circumferential surface at a linear pressure of 50 [N/m], and the developer carrying member has asperities provided on the outer circumferential surface so that the contact area ratio is not less than 5% and not more than 20%.