Claims
- 1. An image forming apparatus comprising:
- a photosensitive member having an amorphous carbon layer on an outer surface thereof; and
- a developing device accommodating a toner for developing an electrostatic latent image formed on the surface of the photosensitive member, said toner comprising a binder resin, a colorant and minute particles each of which has a size of 1.0 .mu.m or less and at least one of an octahedron shape and an irregular shape, having a ratio of 1/R exceeding 10 in less than 80% of the particles on the basis of the total number of minute particles wherein 1 is the maximum length of a particle and R is a diameter of a column having the longest portion of the particle as a central axis, and having a shape coefficient SF1 smaller than 120 and a shape coefficient SF2 smaller than 110 in less than 80% of the particles on the basis of the total number of minute particles wherein SF1={(the maximum length).sup.2 /(an area)}.times.(.pi./4).times.100 wherein the maximum length is a mean value of maximum lengths in projected images of particles and an area is a mean value of projected areas of particles and wherein SF2={(a circumferential length).sup.2 /(an area)}.times.{100/(4.pi.)} wherein a circumferential length is a mean value of circumferential lengths in projected images of particles and an area is a mean value of projected areas of particles, which minute particles have a multi-point contact with the surface of the photosensitive member sufficient to scrape off said surface thereof.
- 2. An image forming apparatus as claimed in claim 1, wherein the minute particles in the toner rub the surface of the photosensitive member.
- 3. An image forming apparatus as claimed in claim 1, wherein the toner is composed of resin and minute particles, the toner containing 0.1-40 weight parts of the minute particles with respect to 100 weight parts of the resin.
- 4. An image forming apparatus as claimed in claim 1, wherein the minute particles are magnetic particles.
- 5. An image forming apparatus as claimed in claim 1, wherein the octahedron shape has a face contact or a crest line contact with the surface of the photosensitive member.
- 6. An image forming apparatus comprising:
- a photosensitive member having an amorphous carbon layer on an outer surface thereof; and
- a developing device accommodating a toner and a carrier for use of developing an electrostatic latent image formed on the surface of the photosensitive member, said carrier comprising minute particles each of which has a size of 200 .mu.m or less and at least one of an octahedron shape and an irregular shape, having a ratio of 1/R exceeding 10 in less than 80% of the particles on the basis of the total number of minute particles wherein 1 is the maximum length of a particle and R is a diameter of a column having the longest portion of the particle as a central axis, and having a shape coefficient SF1 smaller than 120 and a shape coefficient SF2 smaller than 110 in less than 80% of the particles on the basis of the total number of minute particles wherein SF1={(the maximum length).sup.2 /(an area)}.times.(.pi./4).times.100 wherein the maximum length is a mean value of maximum lengths in projected images of particles and an area is a mean value of projected areas of particles and wherein SF2={(a circumferential length).sup.2 /(an area)}.times.{100/(4.pi.)} wherein a circumferential length is a mean value of circumferential lengths in projected images of particles and an area is a mean value of projected areas of particles, which minute particles have a multi-point contact with the surface of the photosensitive member sufficient to scrape off said surface thereof.
- 7. An image forming apparatus as claimed in claim 6, wherein the minute particles in the carrier sweep the surface of the photosensitive member.
- 8. An image forming apparatus as claimed in claim 6, wherein the carrier is composed of resin and minute particles, the carrier containing 200-600 weight parts of the minute particles with respect to 100 weight parts of the resin.
- 9. An image forming apparatus as claimed in claim 6, wherein the octahedron shape has a face contact or a crest line contact of the minute particles with the surface of the photosensitive member.
- 10. An image forming apparatus as claimed in claim 6, wherein the minute particles are magnetic particles.
- 11. A method for treating a photosensitive member having an amorphous carbon layer on an outer surface thereof and provided in an image forming apparatus comprising the steps of:
- supplying a member including minute particles; and
- rubbing the surface of the photosensitive member by means of said member comprising minute particles each of which has a size of 200 .mu.m or less and at least either an octahedron shape and an irregular shape, having a ratio of 1/R exceeding 10 in less than 80% of the particles on the basis of the total number of minute particles wherein 1 is the maximum length of a particle and R is a diameter of a column having the longest portion of the particle as a central axis, and having a shape coefficient SF1 smaller than 120 and a shape coefficient SF2 smaller than 110 in less than 80% of the particles on the basis of the total number of minute particles wherein SF1={(the maximum length).sup.2 /(an area)}.times.(.pi./4).times.100 wherein the maximum length is a mean value of maximum lengths in projected images of particles and an area is a mean value of projected areas of particles and wherein SF2={(a circumferential length).sup.2 /(an area)}.times.{100/(4.pi.)} wherein a circumferential length is a mean value of circumferential lengths in projected images of particles and an area is a mean value of projected areas of particles, which minute particles have a multi-point contact with the surface of the photosensitive member sufficient to scrape off said surface thereof.
- 12. A method as claimed in claim 11, wherein the octahedron shape has a face contact or a crest line contact with the surface of the photosensitive member.
- 13. An image forming apparatus as claimed in claim 11, wherein the minute particles are magnetic particles.
- 14. An image forming apparatus comprising:
- a photosensitive member having an amorphous carbon layer on a surface thereof;
- a developing device accommodating a toner for developing an electrostatic latent image formed on the surface of the photosensitive member; and
- a cleaner for cleaning a residual toner on the surface of the photosensitive member, said cleaner including minute particles each of which has a size of 1.0 .mu.m or less and at least one of an octahedron shape and an irregular shape having a ratio of 1/R exceeding 10 in less than 80% of the particles on the basis of the total number of minute particles wherein 1 is the maximum length of a particle and R is a diameter of a column having the longest portion of the particle as a central axis, and having a shape coefficient SF1 smaller than 120 and a shape coefficient SF2 smaller than 110 in less than 80% of the particles on the basis of the total number of minute particles wherein SF1={(the maximum length).sup.2 /(an area)}.times.(.pi./4) 100 wherein the maximum length is a mean value of maximum lengths in projected images of particles and an area is a mean value of projected areas of particles and wherein SF2={(a circumferential length).sup.2 /(an area)}.times.(100/(4.pi.)} wherein a circumferential length is a mean value of circumferential lengths in projected images of particles and an area is a mean value of projected areas of particles, which minute particles have a multi-point contact with the surface of the photosensitive member sufficient to scrape off said surface thereof.
- 15. An image forming apparatus as claimed in claim 14, wherein the magnetic particles in the cleaner rubs the surface of the photosensitive member.
- 16. An image forming apparatus as claimed in claim 14, wherein the cleaning means is a magnetic brush cleaner.
- 17. An image forming apparatus as claimed in claim 14, wherein the octahedron shape has a face contact or a crest line contact with the surface of the photosensitive member.
- 18. An image forming apparatus as claimed in claim 14, wherein the cleaner is composed of resin and the magnetic particles, the cleaner having 200-600 weight parts of the magnetic particles with respect to 100 weight parts of the resin.
Parent Case Info
This application is a continuation of application Ser. No. 07/651,604, filed on Feb. 6, 1991, now abandoned.
US Referenced Citations (13)
Foreign Referenced Citations (3)
Number |
Date |
Country |
50-45639 |
Apr 1975 |
JPX |
54-51844 |
Apr 1979 |
JPX |
62-34182 |
Feb 1987 |
JPX |
Non-Patent Literature Citations (2)
Entry |
Patent Abtract of Japan, vol. 15, No. 347, (P1246), for Japanese Kokai 03-131866, Published Jun. 5, 1991. |
Patent Abstract of Japan, vol. 15, No. 347, (P1246), for Japanese Kokai 03-131864, Published Jun. 5, 1991. |
Continuations (1)
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Number |
Date |
Country |
Parent |
651604 |
Feb 1991 |
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