JPS62229260A - Printing device - Google Patents

Abstract

PURPOSE:To transfer an image to an ordinary paper by a toner to which plural conductive parts an insulating material electrically independent of one another exist on the surface of an insulating material. CONSTITUTION:With respect to the structure of the toner, plural conductive parts 24 electrically independent of one another are provided on the toner surface consisting of an insulating material 25 as shown in a figure (b). As shown in a figure (a), a recording medium 17 is put on the surface of an image forming body 4 on which a toner image is formed, and ions having a polarity opposite to that of the electric charge in the conductive parts 24 of a toner 7 are injected from the rear side of a transfer form by a corona transfer device 20. In this case, the electric charge of the conductive part 24 brought into contact with the recording medium 17 and conductive parts 24 electrically connected to said conductive part 24 is neutralized momently and does not contribute to the transfer of the image to the recording medium 17. Since the relaxation time of the electric charge of conductive parts 24 which is not neutralized and remains is long, the electrostatic force acts between the recording medium 17 and conductive parts as the transfer force to make the image transfer to an ordinary paper possible.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a printing device using a photoconductor, the so-called xerography technique, and more particularly to a printing device that is realized using a toner with a special structure. [Traditional technology] In recent years, printing devices using zerography technology have been used and used in this technology. Then, in the case of a printing device using the "Carlson process", insulating non-magnetic toner is used in two-component magnetic brush development method or float electrode effect development method (IFIIKD method), and insulating magnetic toner is used in jumping development method. In the case of electrofaxes, conductive magnetic toner is used.In recent years, there has also been a trend toward forming images by simultaneously performing exposure and development, which has the potential to greatly simplify the process. A method using new xerography technology (hereinafter referred to as the simultaneous method)
However, it has been studied in various places, for example, Japanese Patent Application Laid-Open No. 58-153957.
has been proposed.

In this method, it is considered that the optimal development method is to rub the surface of the image forming body containing the photoconductor layer with a conductive magnetic toner brush to which a bias voltage is applied during exposure. When the conductor acts as an insulator (unexposed area) and when it acts as a conductor (I! light area),
A difference occurs in the amount of charge injected into the toner that is in contact with the surface of the image forming body due to the bias voltage, and the difference in the amount of charge becomes a difference in the electrostatic adhesion force to the surface of the image forming body, making it possible to form a toner image. It becomes.

[Problem that the invention seeks to solve]

However, due to the conductivity of the toner used in the simultaneous method, the electric charge on the toner is neutralized in a short relaxation time, causing it to lose its residual charge and lose its electrostatic adhesion to paper. The electric transfer method has the drawback of not being able to transfer images to paper sufficiently.An object of the present invention is to provide a printing device using the simultaneous method that does not have the above drawbacks. Specifically, it is an object of the present invention to provide a toner that can be used to form images using a simultaneous method and that can be transferred onto plain paper using an electrostatic transfer method.

[Means for Solving the Problems] The printing apparatus according to the present invention is characterized by using a toner having a structure in which the toner surface of an insulating material has vI number of electrically independent conductive parts.

[For production]

When the toner used in the printing apparatus of the present invention has the above configuration, charge injection into the toner in contact with the surface of the image forming body during image formation in the simultaneous method is performed through the conductive part on the toner surface, and during electrostatic transfer. Electrostatic transfer The adhesion force of time to paper is
This charge is responsible.

〔Example〕

Fig. 1 ((+), (6) shows an embodiment of the printing apparatus according to the present invention. Fig. 1 (α) is an overall view and Fig. 1 (b) is an enlarged view of the main part. Belt-shaped transparent support An image forming body 4 formed by laminating a transparent conductor layer 2 and a photoconductor layer 3 on a roller 10 is rotated in the direction of an arrow 5 by a roller 10. 6 is a toner supply device, and a toner 7 is supplied by a magnetic roller. The toner layer thus supplied is conveyed to the surface of the image forming body 40 by a well-known magnetic brush composed of a sleeve 8 and a sleeve 9.The toner layer thus supplied is applied to the image forming body 40 from the side opposite to the exposure side at the same time as or immediately after the exposure 12 by the exposure device 11. It is arranged so as to be in contact with the image forming body 4, and due to the effect of the bias voltage 13 applied between the transparent conductor layer 2 and the sleeve 9, the adhesion force to the surface of the image forming body 4 is increased in the exposed and non-exposed areas. difference resulting in selective toner deposition in response to exposure to form an image.

The exposure device 11 includes a self-focusing rod lens array 14, L
The main components are a CS head substrate 15 and a linear light source 16 made of a halogen lamp or a fluorescent tube.
Regarding the S head, for example, Japanese Patent Application Laid-Open No. 58-195521
has been disclosed.

The image forming body 6 on which the toner image has been formed moves in the direction of the arrow 5, and the recording medium 17 is moved in the direction of the arrow 19 by the conveying roller 18.
The toner image is statically transferred from the image forming body 4 to the recording medium 17 while moving under the well-known corotron 20 facing the image forming body 4 at the same moving speed as the image forming body 4. Electrotransferred. The toner image thus formed on the recording medium 17 passes through a well-known heat fixing roller 21, is fixed, becomes a printed matter, and is discharged in the direction of an arrow 22. After the transfer, the image forming body 4 again reaches the image forming unit consisting of the toner supply device 6 and the exposure device 11 and enters the next printing process, but the residual toner remaining on the image forming body without being transferred is removed. By this time, the charge has been neutralized according to the relaxation time of the toner and image forming body, and the electrostatic adhesion force has weakened, so it is collected by the magnetic brush of the toner supply unit 6 and no previous history remains. The thing is clear.

FIG. 2 shows details of how an image is formed in the printing apparatus according to the present invention. In the figure, the same elements as in FIG. 1 are given the same numbers. The image forming body 4, which is formed by laminating the photoconductor Mi3, the transparent conductor layer 2, and the transparent support layer 1 in this order, is subjected to image exposure 12 when moving in the direction of the arrow 5. A well-known magnetic brush formed using a magnet roller 8 and a sleeve 9 brings the toner layer 23 into contact with the image forming body 4 at the exposed portion. Since a bias voltage 13 is applied to the sleeve 9, the toner in contact with the image forming body 4 has a conductive portion 24 present on each toner.
Charge is injected through the current path formed by the contact between the two, but the injection amount is different between the exposed and unexposed areas, resulting in a difference in the electrostatic adhesion of the toner to the surface of the photoconductor layer 12. Image formation is performed.

As the toner layer 23 moves on the image forming body 4, the relative position of the toners changes, and the current path changes accordingly. Since there are probabilistically multiple current paths to the portion 24, the above-mentioned charge injection occurs reliably.

FIG. 3 shows details of how images are transferred by the electrostatic transfer method in the printing apparatus of the present invention.

In the figure, the same elements as in FIG. 1 are given the same numbers.

A recording medium 17 is placed on the surface of the image forming member 4 on which a toner image has been formed, and from the back side of the transfer paper, a corona transfer device 20 transfers the electric charge (charge injected during image formation) of the conductive portion 24 of the toner 7 to the surface of the image forming member 4. Ions of opposite polarity are implanted.

At this time, the charges on the conductive part that has come into contact with the recording medium 17 and the conductive parts that are electrically coupled to the conductive part are instantly neutralized and do not contribute to the transfer force to the recording medium 17, but on the other hand, they are not neutralized. Since the charge on the conductive portion remaining on the conductive portion has a long relaxation time, electrostatic force acts as a transfer force between it and the recording medium 17, and toner transfer is achieved. Give an example. The structure has a plurality of electrically independent conductive parts 24 on the toner surface of the insulating material 25. As the insulating material 25, any toner material having a volume resistivity of 10 8 Ω·cm or more can be used to maintain sufficient insulation between the conductive parts 24. 26 is fine powder of a well-known insulating magnetic material such as Fe, 04, γ-Ire, O, etc. dispersed in the insulating material 25. As another method for imparting magnetism to the toner, a conductive magnetic material such as iron, cobalt, or nickel may be used for the conductive portion 24.

FIG. 5 shows still another structural example of the toner used in the printing apparatus of the present invention. FIG. 5(a) is an external view;
b) is a sectional view, in which the same elements as in FIG. 4 are given the same numbers. In this structure, an acicular conductor 2 whose side surface is covered with an insulating film 27 penetrates the toner particles.
8 acts as the conductive part 24. As the acicular conductor 28, acicular fine powder such as aluminum is used, and such acicular fine powder can be obtained, for example, by a method of evaporating and recrystallizing the above material in an inert gas, and the insulating film 27 This can be achieved, for example, by forming an oxide film on the surface of the acicular conductor 28.In addition, as a method of imparting magnetism to the toner,
As shown in FIG. 5, insulating magnetic material fine powder 26 may be dispersed, or needle-like fine powder 28 may be made of conductive magnetic material such as iron, cobalt, nickel, etc. Since the conductive portion 24 penetrates through the toner, charge injection into the toner during image formation is more efficient. [Effects of the Invention] As described above, the present invention The printing apparatus uses toner having a structure in which a plurality of electrically independent conductive parts are formed on the toner surface of an insulating material. This is a printing device that uses the simultaneous method, and the number of steps included in the printing cycle is significantly fewer than that of printing devices that use conventional xerography technology, resulting in a smaller, lower-priced printing device. .

The image forming body used in the printing apparatus of the present invention can be used with a belt with a seam or a belt without a seam, but if the belt is without a seam, the circumference of the belt can be shortened regardless of the printing length, so the apparatus can be made more compact. Connect.

Furthermore, the toner conveyance means of the toner supply device of the printing apparatus in the present invention is not limited to only a magnetic brush, and for example, a brush conveyance using a brush made of conductive fibers is also possible. In this case, it is not necessary to contain a magnetic component in the toner, and a magnet roller, which is an expensive component, is not required, which is further advantageous in terms of cost.

[Brief explanation of drawings]

FIGS. 1(α) and (6) are diagrams showing an embodiment of the printing device according to the present invention, FIG. 2 is a diagram showing details of how image formation is performed in the printing device according to the present invention, and FIG. FIGS. 4 and 5 (a) are diagrams showing details of how the printing device according to the invention transfers by the electrostatic transfer method.
+ (6) is a diagram showing an example of the structure of toner used in the printing apparatus according to the present invention. 1... Transparent support 2... Transparent conductor layer 6...
- Photoconductor layer 4... Image forming body 6... Toner supply device 7... Toner 11... Exposure device 1
2... Exposure 13... Bias voltage 17... Recording medium 20... Corotron 23-Toner layer 24...
・Conductive part 25...Insulating material 27...Insulator film 28...Acicular conductor 4 Fig. 1 Fig. 4 Fig. 5

Claims (1)

[Claims] On an image forming body comprising a photoconductor layer, the photoconductor layer is exposed to light, and simultaneously or immediately after the exposure, a toner layer is brought into contact with the image forming body from the side opposite to the exposed side, and By applying an electric field to the photoconductor layer and the toner layer, toner is selectively attached to form an image, and the toner image is transferred from the image forming body onto the recording medium to produce a printed matter. A printing device characterized in that a toner having a structure having a plurality of electrically independent conductive portions on a toner surface of an insulating material is used.