Claims
- 1. A method for forming a toner image on a photosensitive material bearing an electrostatic latent image comprising
- (a) introducing a one component developer consisting of fine toner particles, said particles containing a resin and ferromagnetic powder dispersed in said resin in such a fashion that a portion of said ferromagnetic powder is exposed on the surface of said toner particles, said toner particles having a specific resistivity of at least 10.sup.14 ohm cm and being capable of accepting a triboelectric charge,
- into a toner vessel which includes a regulating plate for controlling the amount of toner to be fed,
- (b) feeding said toner onto a toner feeder comprising a non-magnetic cylinder drum and a plurality of magnets disposed therein so that south and north poles are directed to the inner surface of non-magnetic cylinder,
- (c) carrying said toner, by rotary movement of either said non-magnetic cylinder or said plurality of magnets, along the surface of said non-magnetic cylinder into close proximity to said electrostatic latent image,
- said toner particles developing a triboelectric charge of a polarity opposite to that of said electrostatic latent image during steps (a) through (c) in the absence of a corona discharging device, and
- (d) bringing said toner particles into contact with said electrostatic latent image.
- 2. The method of claim 1 wherein said toner particles have been produced by a spray-drying process.
- 3. The method of claim 1 wherein said triboelectric charge is developed by virtue of mutual friction between toner particles.
- 4. The method of claim 1 wherein said ferromagnetic material is comprised of fine particles of ferrite.
- 5. The method of claim 4 wherein said ferromagnetic material is magnetite.
- 6. The method of claim 5 wherein said magnetite content is greater than 50%.
- 7. The method of claim 1 wherein said resin is selected from the group consisting of styrene resins, acrylic resins, vinyl resins, epoxy resins, cellulose resins, polyurethane resins, copolymers thereof, and mixtures thereof.
- 8. The method of claim 1 wherein said ferromagnetic material comprises particles of a size not exceeding one micron.
- 9. The method according to claim 1 wherein said toner particles are formed with fine projections having a size of 0.2 to 0.3 microns.
Priority Claims (1)
Number |
Date |
Country |
Kind |
49-99385 |
Aug 1974 |
JPX |
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Parent Case Info
This application is a continuation of application Ser. No. 326,588 filed 12/2/81. Which is a division of our co-pending application Ser. No. 832,019 filed Sept. 9, 1977 which in turn was a division of abandoned application Ser. No. 608,274 filed Aug. 27, 1975, both of which claimed the priority of Japanese 99385/1974 filed Aug. 28, 1974.
US Referenced Citations (6)
Divisions (2)
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Number |
Date |
Country |
Parent |
832019 |
Sep 1977 |
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Parent |
608274 |
Aug 1975 |
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Continuations (1)
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Number |
Date |
Country |
Parent |
326588 |
Dec 1981 |
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