Developer-carrying member, method for regeneration thereof and developing apparatus

A regenerated developer-carrying member, comprising:

• a substrate, and
• an electroconductive resin coating layer formed on the substrate,
• wherein the electroconductive resin coating layer has been formed by a method including the steps of:
• scraping a resin coating layer of a used developer-carrying member to form a developer-carrying member surface having an unevenness;
• and
• coating the developer-carrying member surface having the unevenness with a coating layer of a resinous composition comprising at least a binder resin and electroconductive fine powder,
• wherein the scraping step is selected from a group of steps consisting of:
• (A) a step of scraping the resin coating layer of the used developer-carrying member with abrasive particles to scrape off at least a portion of the resin coating layer and forming the unevenness on the developer-carrying member surface showing a central line-average roughness Ra of at most 0.8 μm;
• (B) a step of blasting the resin coating layer of the used developer-carrying member having a cylindrical substrate with particles having an average particle size of 15-250 μm together with air at a discharge pressure of 1×105 Pa-5×105 Pa through a nozzle having an inner diameter which is 0.15-1 times the outer diameter of the substrate to scrape off at least a portion of the resin coating layer, thereby forming a surface having the unevenness showing a central line-average roughness Ra of at most 0.8 μm;
• (C) a step of subjecting the used developer-carrying member having a cylindrical substrate to a liquid honing treatment of ejecting a liquid containing particles having an average of 15-100 μm together with air at a discharge pressure of 1×105 Pa-5×105 Pa through a nozzle having an inner diameter of 0.5-1.0 times the substrate outer diameter onto the resin coating layer of the developer-carrying member to scrape off at least a portion of the resin coating layer, thereby forming a surface having the unevenness showing a central line-average roughness Ra of at most 0.8 μm;
• (D) a step of disposing abrasive particles on the resin coating layer of the used developer-carrying member so that at least a portion of the abrasive particles are movable relative to a support therefor, moving the abrasive particles relative to the resin coating layer to scrape off at least a portion of the resin coating layer, thereby forming a surface having the unevenness showing a central line-average roughness Ra of at most 0.8 μm;
• and
• (E) a step of scraping the resin coating layer of the used developer-carrying member having a cylindrical substrate with an abrasive tape having a surface showing a ten point-average roughness of 6.0-30 μm formed by binding abrasive particles with a binder resin abutted against the resin coating layer at an abutting pressure of 1.0×105-5.0×105 Pa to scrape off at least a portion of the resin coating layer, thereby forming a surface having the unevenness showing a central line-average roughness Ra of at most 0.8 μm.

A developing apparatus, comprising:

• a developer vessel for containing a developer used for developing a latent image to form a toner image;
• a developer-carrying member for carrying the developer and conveying the developer to a developing region;
• a developer layer-regulation member for forming a layer of the developer on the developer-carrying member;
• and
• a latent image-bearing member for bearing thereon the latent image,
• wherein the developer-carrying member is a regenerated developer-carrying member, comprising:
• a substrate;
• and
• an electroconductive resin coating layer formed on the substrate, and
• wherein the electroconductive resin coating layer has been formed through steps of:
• scraping a resin coating layer of a used developer-carrying member to form a developer-carrying member surface having unevenness;
• and
• coating the developer-carrying member surface having the unevenness with a coating layer of a resinous composition comprising at least a binder resin and electroconductive fine powders,
• wherein the scraping step is selected from a group of steps consisting of:
• (A) a step of scraping the resin coating layer of the used developer-carrying member with abrasive particles to scrape off at least a portion of the resin coating layer and forming the unevenness on the developer-carrying member surface showing a central line-average roughness Ra of at most 0.8 μm;
• (B) a step of blasting the resin coating layer of the used developer-carrying member having a cylindrical substrate with particles having an average particle size of 15-250 μm together with air at a discharge pressure of 1×105 Pa-5×105 Pa through a nozzle having an inner diameter which is 0.15-1.0 times the outer diameter of the substrate to scrape off at least a portion of the resin coating layer, thereby forming a surface having the unevenness showing a central line-average roughness Ra of at most 0.8 μm:
• (C) a step of subjecting the used developer-carrying member having a cylindrical substrate to a liquid honing treatment of ejecting a liquid containing particles having an average of 15-100 μm together with air at a discharge pressure of 1×105 Pa-5×105 Pa through a nozzle having an inner diameter of 0.5-1.0 times the substrate outer diameter onto the resin coating layer of the developer-carrying member to scrape off at least a portion of the resin coating layer, thereby forming a surface having the unevenness showing a central line-average roughness Ra of at most 0.8 μm;
• (D) a step of disposing abrasive particles on the resin coating layer of the used developer-carrying member so that at least a portion of the abrasive particles are movable relative to a support therefor, moving the abrasive particles relative to the resin coating layer to scrape off at least a portion of the resin coating layer, thereby forming a surface having the unevenness showing a central line-average roughness Ra of at most 0.8 μm;
• and
• (E) a step of scraping the resin coating layer of the used developer-carrying member having a cylindrical substrate with an abrasive tape having a surface showing a ten point-average roughness of 6.0-30 μm formed by binding abrasive particles with a binder resin abutted against the resin coating layer at an abutting pressure of 1.0×105-5.0×105 Pa to scrape off at least a portion of the resin coating layer, thereby forming a surface having the unevenness showing a central line-average roughness Ra of at most 0.8 μm.