JPS60165675A - Recording method of electrophotographic method using photoconductive toner - Google Patents

Abstract

PURPOSE:To prevent fogging and obtain a sharp image by limiting the gap between a base electrode and a counter electrode within a specific range in a flying process of photoconductive toner from the base electrode to the counter electrode, and applying an AC voltage containing a DC component between both electrodes. CONSTITUTION:The counter electrode 7 is provided opposite the base electrode 2 at an interval of 50mum-1mm., preferably, 100-750mum and the bias voltage consisting of the AC voltage V2 containing a DC voltage V1 is impressed between both electrodes to charge electrostatically the counter electrode 7 negatively. Those DC voltage V1 and AC voltage V2 are impressed in the flying process, so toner particles which are charged electrostatically positively with an electrostatic charge distribution on the base electrode 2 are oscillated with the AC voltage and coagulation is suppressed, thereby collapsing clustes. Consequently, all toner particles which are charged electrostatically positively are easy to fly to the counter electrode 7, so a fogfree sharp image corresponding to a positive original image if obtained in a following transfer process.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a recording method such as an electrophotographic method using a photoconductive toner, and particularly to a recording method such as an electrophotographic method that can obtain a clear image without capri.

[Prior art]

In general, photocopying methods using electrophotographic technology include, for example, the electrofax method in which a direct copy is made on electrophotographic photosensitive paper containing a zinc oxide-resin dispersion system, or the toner powder obtained on an electrophotographic photoreceptor such as selenium. One example is the xerography method, in which a copy is obtained by transferring an image onto plain paper, but both methods require a development step using toner powder, making electrophotographic copying devices complicated and expensive.

In addition, in these methods, the copying system is constructed of independent members such as the photoreceptor and the toner powder or developer (-component system), so of the above two members,
Maintenance is necessary to maintain the performance of the photoreceptor and developer at the desired level, to prevent it from being difficult to obtain high-quality copies due to deterioration of the charging characteristics of the photoreceptor due to optical fatigue. There were problems such as it becoming difficult.

On the other hand, in order to overcome these drawbacks, a photoconductive toner has been developed in recent years that has the functions of both a photoreceptor and a developer.

The present invention is a technology for solving the unique problems that occur in recording methods such as electrophotography using such photoconductive toner.

Conventionally, the method of forming an image using a photoconductive toner is generally to spread the toner onto a conductive support such as a metal plate, charge the toner, expose it to light, and perform transfer. (Refer to Japanese Unexamined Patent Publication No. 53-39750).

However, in the above method, when transferring toner after exposure, a transfer corona with a polarity opposite to that of the toner is applied to selectively transfer only the toner that remains charged in areas other than the light irradiated area to the paper. Because the toner was irradiated with light, it was transferred along with the toner.In order to prevent the transfer characteristics from changing significantly due to changes in the moisture content of the paper,
It is difficult to obtain an image with good gradation, and it also has the drawback of increasing fog. Also, countermeasures such as using electrostatic recording paper can be considered, but this is not preferable because it increases the cost.

On the other hand, for example, JP-A-56-33664 and JP-A-56-33
No. 665 and No. 56-33665 each describe a technique of applying @Yodo voltage or alternating it pressure as a bias voltage in the flight process.

However, in the above technology, during development, the toner particles that have absorbed the light from image exposure actually have a charge distribution, and the toner particles do not move to the counter electrode side simply by applying a DC or AC bias voltage. There is. Under these conditions, if the positive toner image on the base electrode is then transferred to a transfer material such as paper, an image with a lot of fog will be obtained due to the residual of unnecessary toner particles, and the image quality will likely deteriorate. There was a problem.

[Purpose of the invention]

SUMMARY OF THE INVENTION Therefore, it is an object of the present invention to provide a recording method such as an electrophotographic method using a photoconductive toner, which can produce fog-free images with excellent gradation.

[Structure of the invention]

As a result of extensive research, the present inventor has discovered a process of dispersing a photoconductive toner onto a base electrode, a process of charging one layer of the dispersed photoconductive toner, and an image forming process by irradiating the charged toner with light. a step of exposing to light; a step of leaving toner that has lost its charge or has been reversely polarized due to light irradiation on the base electrode; and a step of causing other charged toner to fly toward the counter electrode; A recording method such as an electrophotographic method using a photoconductive toner, which includes a step of transferring the above toner image to a transfer material to obtain a final image, the distance between the base electrode and the counter electrode being 50 μm to 1 m in the flying step. It has been found that the objects of the present invention can be achieved by a recording method such as an electrophotographic method using a photoconductive toner, which is characterized by applying an alternating current voltage containing a direct current component between the two electrodes.

An embodiment of the method of the present invention will be described below with reference to FIGS. 1 to 5.

-4~ First, as shown in FIG. 1, photoconductive toner A is sprayed onto the base electrode 2 from a sprayer 1, and it is desirable that the state after spraying be adjusted so as to form a uniform single layer. As this adjusting means, for example, the illustrated blade 3 is used, and the bill can be adjusted by horizontally moving the blade 3 or the base electrode 2.

A known means may be used for the horizontal movement mechanism. In the above-mentioned step 2, the state after dispersion does not necessarily have to form a strictly uniform single layer as shown in the figure, and a multilayered portion may be formed. In addition, a fur brush method, a powder cloud method, etc. can be applied to apply an appropriate bias voltage to the base electrode 2 side at the time of dispersion.

Next, as shown in FIG. 2, the uniform single layer photoconductive toner A is charged with a corona charger 4, for example. Note that the charging means may be frictional charging using a conductive roller or the like.

Next, as shown in FIG. 3, for example, a positive original 5 is exposed. During exposure, it is desirable that the base electrode 2 be in an electrically conductive state, and if it is in a conductive state, the photoconductive toner A in the light irradiation area 6 (corresponding to the bright area of the original 5) is photoexcited. However, the charge polarity is erased.Depending on the type of photoconductive dove A used, the charge polarity may be reversed, so there is no problem in using such a toner.

Further, in the above exposure, a bias voltage having a polarity opposite to that of the toner charge charge ■ may be applied to the base electrode 2, and in this case, the toner A in the light irradiation section 6 is reversed to the opposite polarity e. On the other hand, the toner A in the light-blocking portion corresponding to the dark portion of the document 5 remains with the polarity of ■.

Note that the exposure direction is not particularly limited, and the photoconductive toner A may be irradiated with light reflected from the original 5. Also, the original 5 may be a negative image, in which case the toner in the light irradiation area A positive image can be obtained by performing the final transfer.

Next, as shown in FIG. 4, the base electrode 2 is coated with 50 to 1 tone.
Preferably, the counter electrodes 7 are disposed opposite each other with an interval of 100 μm to 750 μm, and a bias voltage is applied between the counter electrodes 7 and the base electrode 20 to charge the counter electrodes 7 by θ. This bias voltage applies an AC voltage v2 at the same time as a DC voltage v1, and is one of the features of the present invention.

Details regarding the voltage application means can be found in Japanese Patent Application No. 58-2069.
Reference may be made to the specification of No. 93.

In this way, by simultaneously applying the @applied voltage V1 and the AC voltage (2) during flight, the toner particles charged (2) with the charge amount distribution on the base electrode 2 are
It is vibrated by the voltage, and even if it is in an agglomerated or clustered state, the agglomeration is loosened and the clusters are disintegrated.

For this reason, toner particles are given a sufficient flying probability even if the amount of charge is small, and all of the charged toner particles are in a state where they are likely to fly out to the counter electrode side, so that the original (positive) is transferred by the next transfer. It is possible to obtain a high-quality, fog-free (positive) image that faithfully corresponds to the image.

Next, as shown in FIG. 5, a transfer material such as a paper 8 is placed facing the counter electrode T, and a corona charger 9 is used from the back side of the paper 8 to charge the toner with a polarity O opposite to the charge 7-. , a positive image is obtained by transferring it to paper 7, and fixing it as necessary.

Since the toner in the light irradiation section 6 is thus removed during transfer, a clear image with less capri can be obtained.

Note that during the above transfer, if an AC bias voltage is applied at the same time as in the flying process, the transfer will be performed for the same reason as above.jD)
Since the toner particles are quickly transferred onto the paper 8, the transfer efficiency can be improved.

Next, an example of a preferred mounting for carrying out the method of the present invention will be explained based on FIG.

In this device, a base electrode 2 and a counter electrode 7 are formed face down on a drum, and both electrodes are arranged side by side with an interval of 50 μm=lm. Both electrodes can also be formed by endless belts.

A scatterer 1 and a charger 4 are provided above the base electrode 2,
Uniformly sprayed in a single layer and ■ charged, then exposed to light, ■
Only the charged toner particles fly to the counter electrode 7 and are then transferred to obtain the final positive 8-image. When it is desired to obtain a negative image as the final transferred image, transfer is performed with the lower blade of the base electrode 2, or a toner tube charged to the opposite polarity e is used to fly this θ toner to the counter electrode 7, and then All you have to do is shift the transcription.

In addition, in FIG. 6, 10 is a cleaning blade.

The photoconductive toner used in the method of the present invention is not particularly limited, and any known photoconductive toner can be used without any particular limitation.
No. 58-130357, No. 53-79542, No. 5
3-82417 etc. can be used.

It goes without saying that if toners of colors corresponding to each of the three primary colors are selected as the photoconductive toners used in the present invention and the three colors are scattered in a mosaic pattern, there is a possibility of color variations.

Note that the method of the present invention can be applied to other recording methods that utilize electrostatic charges in addition to electrophotography.

〔Effect of the invention〕

According to the present invention, as is clear from the above, it is possible to obtain an image with excellent gradation and without capri.

[Brief explanation of drawings]

1 to 5 are schematic sectional views showing one embodiment of the present invention,
FIG. 6 is a schematic sectional view showing an example of a preferred apparatus for carrying out the method of the present invention. In the figure, 1 is a scatterer, 2 is a base electrode, 4 is a corona charger, 5 is a document, and 6 is a light beam. Irradiation section, 7
8 indicates the counter electrode, and 8 indicates the paper. Patent applicant / JX Seidai Photo Industry Co., Ltd. Agent Patent attorney Nobuaki Sakaguchi (and 1 other person) 11-

Claims (1)

[Claims] A step of dispersing photoconductive toner on a base electrode, a step of charging one layer of the scattered photoconductive toner, a step of imagewise exposure of the charged toner by light irradiation, and a step of discharging the charge by light irradiation. Namatata d: Reverse polarity! A photoconductive method comprising the steps of leaving the charged toner on the base electrode and causing other charged toner to fly toward the counter electrode, and transferring the toner image on the counter electrode to a transfer material to obtain a final image. A recording method such as an electrophotographic method using a magnetic toner, wherein the distance between the base electrode and the counter electrode is set at 5 in the flying step.
A recording method such as an electrophotographic method using a photoconductive toner, characterized in that an alternating current voltage containing a direct current component is applied between the two electrodes at a voltage of 0 μm to 1 square meter.