Abstract: This electrophotographic photosensitive body (20) comprises a supporting body (20a) and a photosensitive layer (20b) that is formed on the surface of the supporting body (20a). The surface of the photosensitive layer (20b) has an arithmetic mean roughness Ra within the range of from 20 nm to 100 nm (inclusive), a ten-point average roughness Rz within the range of from 0.2 ?m to 1.0 ?m (inclusive) and a mean spacing of profile irregularities Sm of 20 ?m or less in the initial stage of use.

Abstract: This electrophotographic photosensitive body (20) comprises a supporting body (20a) and a photosensitive layer (20b) that is formed on the surface of the supporting body (20a). The surface of the photosensitive layer (20b) has an arithmetic mean roughness Ra within the range of from 20 nm to 100 nm (inclusive), a ten-point average roughness Rz within the range of from 0.2 ?m to 1.0 ?m (inclusive) and a mean spacing of profile irregularities Sm of 20 ?m or less in the initial stage of use.

Abstract: An image forming apparatus includes an image carrying member, a driving device, a charging member, a cleaning member, a voltage applying device, a torque detector for detecting the torque of the driving device, a storage for storing a predetermined torque value Tc, and a control portion. The control portion obtains as Ton the torque when the charging voltage is applied to the charging member and obtains as Toff the torque when no charging voltage is applied to the charging member. Let the torque observed when no charging voltage is applied at an early stage of use of the image carrying member be represented by Toff(0), then, when the relations Toff(0)<Toff and Tc<Ton/Toff hold, the control portion determines that the degree of smoothness of the surface of the image carrying member is equal to or higher than a predetermined degree of smoothness.

Abstract: An image forming apparatus includes an image carrying member, a driving device, a charging member, a cleaning member, a voltage applying device, a braking distance detector, a storage for storing a predetermined braking distance value Lc, and a control portion. The control portion obtains as Lon a braking distance when a charging voltage is applied to the charging member and obtains as Loff a braking distance when no charging voltage is applied to the charging member. Let the braking distance observed when no charging voltage is applied at an early stage of use of the image carrying member be represented by Loff(0), then, when the relations Loff<Loff(0) and Lc<Loff/Lon hold, the control portion determines that the degree of smoothness of the surface of the image carrying member is equal to or higher than a predetermined degree of smoothness.

Abstract: An image forming device includes an image carrier on the surface of which a toner image is formed, a cleaning member arranged in contact with, for cleaning, the surface of the image carrier, a charging member for electrostatically charging the image carrier, a bias applying device, and a control portion. The bias applying device applies a charging bias having DC and AC biases superimposed on each other to the charging member. The control portion controls the charging bias applied to the charging member by the bias applying device. As the AC bias applied to the charging member, the control portion uses, in a first period from the start of use of the image carrier to a predetermined time thereafter, a first AC bias and, in a second period subsequent to the first period, a second AC bias higher than the first AC bias.

Abstract: An image forming apparatus includes an image carrying member, a driving device, a charging member, a cleaning member, a voltage applying device, a torque detector for detecting the torque of the driving device, a storage for storing a predetermined torque value Tc, and a control portion. The control portion obtains as Ton the torque when the charging voltage is applied to the charging member and obtains as Toff the torque when no charging voltage is applied to the charging member. Let the torque observed when no charging voltage is applied at an early stage of use of the image carrying member be represented by Toff(0), then, when the relations Toff(0)<Toff and Tc<Ton/Toff hold, the control portion determines that the degree of smoothness of the surface of the image carrying member is equal to or higher than a predetermined degree of smoothness.

Abstract: An image forming apparatus includes an image carrying member, a driving device, a charging member, a cleaning member, a voltage applying device, a braking distance detector, a storage for storing a predetermined braking distance value Lc, and a control portion. The control portion obtains as Lon the braking distance when the charging voltage is applied to the charging member and obtains as Loff the braking distance when no charging voltage is applied to the charging member. Let the braking distance observed when no charging voltage is applied at an early stage of use of the image carrying member be represented by Loff(0), then, when the relations Loff<Loff(0) and Lc<Loff/Lon hold, the control portion determines that the degree of smoothness of the surface of the image carrying member is equal to or higher than a predetermined degree of smoothness.

Abstract: An image forming device includes an image carrier on the surface of which a toner image is formed, a cleaning member arranged in contact with, for cleaning, the surface of the image carrier, a charging member for electrostatically charging the image carrier, a bias applying device, and a control portion. The bias applying device applies a charging bias having DC and AC biases superimposed on each other to the charging member. The control portion controls the charging bias applied to the charging member by the bias applying device. As the AC bias applied to the charging member, the control portion uses, in a first period from the start of use of the image carrier to a predetermined time thereafter, a first AC bias and, in a second period subsequent to the first period, a second AC bias higher than the first AC bias.

Abstract: An image forming apparatus has an image carrying body, a first electrically conductive member, a bias application device, and a controller. The first electrically conductive member makes contact with the photosensitive layer of the image carrying body The bias application device applies a bias containing an AC bias to the first electrically conductive member. The controller controls the bias application device. The image forming apparatus can execute, while no image formation is being performed, a temperature raising mode in which, with the first electrically conductive member in contact with the image carrying body outside the image formation region, an AC bias having a peak-to-peak value twice as high as the discharge start voltage between the first electrically conductive member and the image carrying body is applied to the first electrically conductive member to raise the temperature of the surface of the image carrying body.

Abstract: An image forming apparatus includes an image bearing member, a conductive member, a bias application device, and a control portion. The image bearing member has a photosensitive layer formed on an outer peripheral surface thereof. The conductive member is disposed so as to make contact with an inner peripheral surface of the image bearing member and has a dielectric property. The bias application device applies a bias including an alternating current bias to the conductive member. The control portion controls the bias application device. The image forming apparatus is capable of executing a heating-up mode in which an alternating current bias having a peak-to-peak value twice or more as large as a discharge start voltage between the conductive member and the image bearing member is applied to the conductive member to cause the surface of the image bearing member to be heated up.

Abstract: An image forming apparatus includes an image bearing member, a first conductive member, a bias application device, and a control portion, and performs image formation on a surface of the image bearing member while making the image bearing member rotate. The image forming apparatus is capable of executing a heating-up mode in which, at the time of non-image formation, in a state where the image bearing member is made to rotate at a velocity lower than that used at the time of image formation, an alternating current bias having a frequency higher than that used at the time of image formation and a peak-to-peak value twice or more as large as a discharge start voltage between the first conductive member and the image bearing member is applied to the first conductive member to cause a surface of the image bearing member to be heated up.

Abstract: A charge applying member includes a conductive roller and a shaft. The conductive roller includes a first region in contact with a member to be charged and facing an image forming region of the member to be charged and a second region next to a longitudinal end of the first region and facing a region of the member to be charged outside the image forming region and is configured to apply a charge to the member to be charged. The shaft formed of a metallic material inserted into the conductive roller and configured to be given a voltage from a power supply. A region plated with a metal having a lower ionization tendency than the shaft is formed as a plated region on a surface portion of the shaft corresponding to the first and second regions and a non-plated region is formed on a surface portion of the shaft corresponding to the second region.

Abstract: An image forming apparatus includes an image bearing member, a conductive member, a bias application device, and a control portion. The image bearing member has a photosensitive layer formed on an outer peripheral surface thereof. The conductive member is disposed so as to make contact with an inner peripheral surface of the image bearing member and has a dielectric property. The bias application device applies a bias including an alternating current bias to the conductive member. The control portion controls the bias application device. The image forming apparatus is capable of executing a heating-up mode in which an alternating current bias having a peak-to-peak value twice or more as large as a discharge start voltage between the conductive member and the image bearing member is applied to the conductive member to cause the surface of the image bearing member to be heated up.

Abstract: An image forming apparatus has an image carrying body, a first electrically conductive member, a bias application device, and a controller. The first electrically conductive member makes contact with the photosensitive layer of the image carrying body The bias application device applies a bias containing an AC bias to the first electrically conductive member. The controller controls the bias application device. The image forming apparatus can execute, while no image formation is being performed, a temperature raising mode in which, with the first electrically conductive member in contact with the image carrying body outside the image formation region, an AC bias having a peak-to-peak value twice as high as the discharge start voltage between the first electrically conductive member and the image carrying body is applied to the first electrically conductive member to raise the temperature of the surface of the image carrying body.

Abstract: An image forming apparatus includes an image bearing member, a first conductive member, a bias application device, and a control portion, and performs image formation on a surface of the image bearing member while making the image bearing member rotate. The image forming apparatus is capable of executing a heating-up mode in which, at the time of non-image formation, in a state where the image bearing member is made to rotate at a velocity lower than that used at the time of image formation, an alternating current bias having a frequency higher than that used at the time of image formation and a peak-to-peak value twice or more as large as a discharge start voltage between the first conductive member and the image bearing member is applied to the first conductive member to cause a surface of the image bearing member to be heated up.

Abstract: A charge applying member includes a conductive roller and a shaft. The conductive roller includes a first region in contact with a member to be charged and facing an image forming region of the member to be charged and a second region next to a longitudinal end of the first region and facing a region of the member to be charged outside the image forming region and is configured to apply a charge to the member to be charged. The shaft formed of a metallic material inserted into the conductive roller and configured to be given a voltage from a power supply. A region plated with a metal having a lower ionization tendency than the shaft is formed as a plated region on a surface portion of the shaft corresponding to the first and second regions and a non-plated region is formed on a surface portion of the shaft corresponding to the second region.