Claims
- 1. A process of making an insulating magnetic toner, useful as a one component developer for electrophotography comprising the steps of mixing ferromagnetic particles, a thermoplastic resin and a charge controlling agent, heat kneading, cooling and granulating the resulting mixture into fine particles, contacting the fine particles with a hot gas of a temperature higher than the toner softening point and lower than 500.degree. C. for a length of time sufficient so that particles smaller than about 1 .mu.m in size fuse to larger particles thereby reducing the content in percent by weight of the toner particles smaller than about 1 .mu.m in size to a range between 0.10 and 0.00, cooling the particles and then selecting the particles having an average particle size in the range of about 7 to about 30 .mu.m.
- 2. A process of making an insulating magnetic toner according to claim 1, wherein the toner contains about 20 to 70 parts of ferromagnetic material per 100 parts by weight of the toner.
- 3. A process of making an insulating toner according to claim 1, wherein the toner contains a colorant.
- 4. An insulating magnetic toner useful as a one component developer for electrophotography prepared by a process comprising the steps of mixing ferromagnetic particles, a thermoplastic resin and a charge controlling agent, heat kneading, cooling and granulating the resulting mixture into fine particles, contacting the fine particles with a hot gas of a temperature higher than the toner softening point and lower than 500.degree. C. for a length of time sufficient so that particles smaller than about 1 .mu.m in size fuse to larger particles thereby reducing the content in percent by weight of the toner particles smaller than about 1 .mu.m in size to a range between 0.10 and 0.00 cooling the particles and selecting the particles having an average particle size in the range of about 7 to about 30 .mu.m.
- 5. An insulating magnetic toner according to claim 4, wherein the toner contains about 20 to 70 parts of ferromagnetic material per 100 parts by weight of the toner.
- 6. An insulating magnetic toner according to claim 4, wherein the toner contains a colorant.
Priority Claims (1)
Number |
Date |
Country |
Kind |
50/134570 |
Nov 1975 |
JPX |
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REFERENCE TO RELATED CO-PENDING APPLICATION
This is a continuation application of U.S. Ser. No. 739,130, filed Nov. 5, 1976, now abandoned.
US Referenced Citations (6)
Foreign Referenced Citations (1)
Number |
Date |
Country |
2538112 |
Mar 1976 |
DEX |
Continuations (1)
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Number |
Date |
Country |
Parent |
739130 |
Nov 1976 |
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