JPS58140769A - Toner image transferring method - Google Patents

Abstract

PURPOSE:To allow a simple device to perform clear toner image transfer while holding stable and high transfer efficiency by applying a corona ion flow which is asymmetrical about the moving direction of a transfer material to the back surface of the transfer material, and thus moving toner particles from an image carrier to the transfer material. CONSTITUTION:The cover plate of a corona discharger 1 is separated into the entry-side cover plate 3 and the exit-side cover plate 3' of the transfer material P and a discharging wire 2 is applied with a DC voltage having the opposite polarity of charges of toner 5 on the image carrier 4 from a DC power source E; and the entry-side cover plate 3 is applied with a DC voltage having the same polarity with the voltage applied to the discharging wire 2 from a DC power source E' and the exist-side cover plate 3' is applied with a DC voltage having the same polarity from a DC power source E''. The corona ion flow applied to the back surface of the transfer material P from the discharging wire 2 deviates weakly to the entry side of the transfer material P and intensely to the exit side in an transfer area (a), so the partial movement of the toner 5 in an area (b) before the transfer area and the repulsion of the toner 5 in a separation area are eliminated, performing transfer free of image disorder.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a toner image transfer method such as in the art, and in particular to an improvement in a toner image transfer method using a corona discharger.

In the conventional toner image transfer method using a corona discharger, as shown in Figure 1, a DC voltage is applied to the discharge wire of the corona discharger, the cover plate 3 is grounded,
Alternatively, by applying a direct current voltage to a scorotron (not shown) lid, a constant corona ion flow of polarity opposite to that of the toner j on the image carrier is generated from a discharge wire to the back surface of the transfer material P. The toner image on the image carrier q is transferred in the transfer area a by charging the transfer material P to a polarity that attracts the donor on the image carrier q.
KL' is transferred to photographic material P. This transfer method does not require special adhesive transfer materials as in adhesive transfer, and there is no risk of toner image collapse as in adhesive transfer or electrostatic transfer using an electrode roller. It is an excellent method as it can provide a relatively high transfer effect and the device configuration is simple.

My intuition is that in this conventional method, if the charge retention of the transfer material P decreases due to factors such as humidity, the transfer efficiency will decrease, and in order to increase the transfer efficiency, the direct current corona ion flow is strengthened. Then, in the transfer area a, the charge due to the corona ion flow passes through the transfer material P to the toner! The toner J is charged with the same polarity as the charge of the corona ion flow, and the toner 3 is repelled from the transfer material P, which may actually reduce the transfer efficiency or cause image disturbance. There is.

In addition, some of the toner j on the image carrier is transferred to the transfer material P in the pre-transfer area due to being attracted by the strongly charged transfer material P, which also causes image disturbance, and furthermore, corona Since the ion flow is symmetrical with respect to the traveling direction of the transfer material P, the transfer efficiency decreases and image disturbance occurs due to the same reasons in the separation area 0 following the transfer area a as in the transfer area a and the pre-transfer area bK. There is a problem in that the discharge conditions of the corona discharger 1 are limited to an extremely narrow range in order to avoid this problem.

The present invention has been made in order to solve the above-mentioned problems of the transfer method using a corona discharger, and by pouring a corona ion flow that is asymmetrical with respect to the traveling direction of the transfer material onto the back surface of the transfer material, toner particles are A transfer method in an electrostatic recording apparatus that solves the above-mentioned problem is that the transfer material is transferred from an image carrier to a transfer material.

The present invention will be explained below based on the embodiments shown in FIGS. 1 to 3.

In the embodiment shown in FIG. 2, the cover plate of the corona discharger l is divided into a cover plate 3 on the entrance side of the transfer material P and a cover plate 3' on the exit side, and the discharge wire is used to carry the toner on the image carrier. A DC voltage of about 10 kV with the opposite polarity to the charging voltage is applied to the DC power supply E, and a discharge wire is applied to the cover plate 3 on the entry side. ′ is applied,
A DC voltage of about λkV of the same polarity is applied to the outlet cover plate 3' by a DC power source E'.

As a result, the corona ion flow poured from the discharge wire onto the back side of the transfer material P is strongly biased toward the entrance side of the transfer material P in the transfer area a, and weakly biased toward the exit side 9. Therefore,
Partial transfer of toner J in the pre-transfer area and repulsion of toner J in separation area C, which occur in the conventional corona discharge transfer method, are eliminated, and the transfer is performed stably without image disturbance. .

That is, the results of implementing this method on an electrophotographic copying machine U-Bix V manufactured by Konishiroku Photo Industry Co., Ltd. were as follows: When comparing nine cases using a corona discharger as shown in Figure 1, there was little difference in transfer efficiency of 70 to 10%, but the stability of the clarity of the transferred image was excellent.

In the embodiment shown in FIG. 3, the rectifying element 4.6' has a cover plate J on the inlet side and a cover plate 3' on the outlet side in which the current direction is opposite.
This is different from the embodiment shown in Fig. 1 in that an AC power supply with a frequency of 10 Hz -/Do kHz and a voltage of at most 1 to 100 mVlili is connected via the 10 Hz -/Do kHz circuit, whereby the corona ion flow is as described in Fig. 2. Not only is the degree of bias changed periodically, but the transfer efficiency is not only stably performed without image disturbance, but also the transfer efficiency is significantly improved.

That is, this method was applied to a copying machine U-
When applied to BiX V, the results showed that a stable transfer image was obtained, and the transfer efficiency was high at 7j-II%O, which was the same as that of the conventional transfer method as shown in Figure 1. The transfer efficiency was improved by an average of j% compared to the transfer efficiency of a copying machine. The reason for this is: - Since a vibration element is added to the corona ion flow, the average charging voltage value of the transfer material P does not become higher than necessary, even if the intensity of the instantaneous corona ion flow becomes strong. The fact that charge of the corona ion flow is injected into the toner J is reduced; ■ The corona ion flow that varies by 4 is more effective in transferring the toner S than the constant corona ion flow; ■ The average of the transfer material P. Since the charging voltage value does not become higher than necessary, not only is it possible to prevent the toner j from being charged with the same polarity in the transfer area a, but also toner j has partially migrated in the pre-transfer area and in the separation area 0. It is thought that the repulsion of toner j disappears, and the cape.

The embodiment shown in Fig. 1 has a discharge wire with a frequency of 10H1 to 1.
The difference from the embodiment shown in FIG. 2 is that an alternating current voltage of 00 kHz and a voltage of 10 kV is applied, so that the corona ion flow has a polarity opposite to that of the toner j on the entrance side of the transfer material P. ions, and the exit side is biased to be rich in ions of the same polarity as the charge of toner j,
Moreover, the intensity changes periodically. By pouring such a corona ion flow onto the back surface of the transfer material P in the transfer area a, not only is the transfer performed stably without image disturbance, but the transfer efficiency is further improved, and the post-transfer An excellent effect can be obtained in that the transfer material P can be easily separated. In other words, this method was applied to a copying machine υ− manufactured by Konishiroku Photo Industry Co., Ltd.
The results using Bix VK show that the transfer efficiency is 10-90%.
This is an improvement of 10% on average compared to conventional transfer methods, and clear transferred images can be stably obtained.

The reason for this is that the effects explained in the example of Figure 3 become even greater; (1) ions of opposite polarity are also added to the ion flow, which increases the effect of changes in Io and Jl; (2) The average voltage applied to the transfer material became lower. It goes without saying that the DC power supply as in the example of FIGS. 1 and 2 can be realized by using a resistor, a rectifying element, and a Zener diode cape in an AC power supply.

In the zl11tv embodiment, a pulsating voltage is applied to the discharge wire JK of the corona discharger L via the rectifying element 6 from the AC power source M, and the cover plate 3 on the entrance side of the transfer material P is directly connected to the discharge wire JK of the corona discharger L. The cover plate 3' on the output side of P is grounded via a rectifying element 6' so that it is charged with corona ions.
More of the pulsating corona ion flow is poured onto the back surface of the transfer material P on the entrance side of the transfer material P.

This method also uses a copying machine U-Bix V manufactured by Konishiroku Photo Industry Co., Ltd.
When I carried it out, I obtained almost the same results as the method shown in Figure 3. Circle.

The present invention is not limited to the above example in which the liquid shape is a sine wave when an AC power source is used, and the present invention is not limited to the above example. A method using a Rotron grid may also be used. In other words, the storage area of the scorotron grid is changed between the entrance and exit sides of the transfer material, the scorotron grid is divided into the entrance and exit sides, and the voltage applied to them is changed, or the scorotron grid is further divided into the entrance and exit sides. This can be done by pulsating the voltage applied to the grid. Further, two or more discharge wires may be used in the corona discharger, and the voltages applied to them may be varied.

As described above, according to the present invention, it is possible to perform nine-clear toner image transfer with a stable and high transfer efficiency using a simple device.

[Brief explanation of drawings]

FIG. 1 is a partial block diagram of an electrophotographic recording apparatus showing a conventional transfer method, and FIGS. 1 to 5 are partial block diagrams of an electrophotographic recording apparatus showing an example of the transfer method of the present invention. l...corona discharger, c...discharge wire, 3
．． 3/...cover plate, ri...image carrier, j.
... Toner, 6. t'... Rectifying element, a
...transcription area, b...pretranscription area, C...
・Separation area, P... Transfer material, E, Ii:'
J'...DC power supply, A (3...AC power supply. Figure 1 Figure 20 43 Figure 4-Figure 5 Procedural amendment letter S/1980 λ1 Haruyuki Shimada, Commissioner of the Patent Office Tono 1. Display of the case 1939, Patent Application No. 21??7 No. 3, Person making the amendment Relationship with the case Patent applicant Mvl 1-26 Nishi-Shinjuku, Shinjuku-ku, Tokyo! Name (
Name) (H7) Konishi Roku Photo Industry Co., Ltd. Kinsha 6, number of inventions increased by amendment None 1) Specification, page 7, line 1I, “strong, weak on the exit side” (2) Correct "rich in ions of the same polarity" to "rich in ions of the opposite polarity" in lines 1 to λ of page 7. 3) In the same article, page 7, lines 1I to 19, "resistance, rectifying element," is corrected to "rectifying element, e.g.".'(4
) Same as above, delete "K to be charged with corona ions" on page 1, line j. (5) - Correct the ``approach side'' in the 7th line of the page to ``exit side'' in the same section. that's all

Claims (1)

[Claims] 1. Toner particles are transferred from the image carrier to the transfer material by pouring a co-ron ion flow onto the back surface of the transfer material, which is asymmetrical with respect to the direction of movement of the transfer material. A toner image transfer method characterized by: 2. A toner image transfer method according to claim 1, wherein the corona ion flow has a vibration component. The toner image transfer method according to claim 81 or 2. East Claim 1, wherein the toner particles are insulating.
Toner 1 transfer method as described in items 1 to 5.