JPH08179606A - Tower image recorder and developer - Google Patents

Abstract

PURPOSE: To inhibit the biased use of toner (selective development) and to achieve long-life development and the stability of image quality, in the development of an electric-charge latent image by the use of color toners in a toner recorder for electrophotography, and the like. CONSTITUTION: To preferentially use older toner in accordance with its retention time in a developing unit 4, (1) when the operating point of change amount of toner is in an area where the amount of the toner stuck to a photoconductive drum 1 decreases with an increase in the amount of the charge, such a developer having characteristics that the amount of the toner charge gradually decreases as the toner to be used becomes older is used, or (2) when the operating point of the charge amount of the toner is in an area where the amount of the toner stuck to the photoreceptor drum 1 increases with the amount of the charge, such a developer having characteristics that the amount of the toner charge gradually increases as the toner to be used become older is used.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toner image recording device (developing device) and a developer used for electrophotography and electrostatic recording.

[0002]

2. Description of the Related Art This type of device visualizes a charge latent image by supplying charged colored particles (toner) to the charge latent image (electrostatic latent image) formed on a photosensitive drum. In such a developing device, a one-component developer containing a charged toner as a main component and the toner and a small amount of an external additive (one-component developing method), a toner and a carrier (toner carrying toner, Which has the role of charging and transporting) and a component using a two-component developer containing a small amount of an external additive (two-component developing method). Regarding the toner image recording apparatus and the developer by these developing methods, Japanese Patent Publication No. 60-3
No. 0946, Japanese Patent Publication No. 63-25350, Japanese Patent Fair 1-5
No. 2754, Japanese Patent Publication No. 59-13023 and the like.

[0003]

In the conventional toner image recording apparatus and developer, each toner in the developer in the developing device has the same proportion in the process of forming an image during development (during the toner image recording process). There is a case where so-called selective development occurs in which the toner is not used in the process but is consumed unevenly. When such selective development occurs, old toner accumulates and the characteristics of the developer remaining in the developing device change (deterioration of properties), the developer cannot be used for a long period of time, and the life of the developer or the developing device is shortened. However, there is a problem that it is difficult to collect the waste toner generated during image formation and reuse it.

The present invention has been made in view of the above points, and an object thereof is to solve various problems associated with selective development, to provide a recording apparatus and a developer which can reduce reuse of the discharged toner with little fluctuation in image quality over a long period of time. To provide.

[0005]

SUMMARY OF THE INVENTION The above object is to make it possible to preferentially consume old toner (toner having a long residence time) and collected discharged toner out of the toner existing in the developing device. Can be achieved.

Therefore, in the present invention, in a toner image recording apparatus for developing a latent charge image with a charged colored toner, the operating point of the charge amount of the toner is such that when the charge amount increases, the amount of toner adhered to the photosensitive drum decreases. In the area where the toner is used, a developer having a characteristic that the toner charge amount gradually decreases as the used toner ages, or the operating point of the toner charge amount is such that when the charge amount increases, the toner to the photosensitive drum It is characterized by using a developer having a characteristic that the toner charge amount gradually increases as the used toner ages when it is in a region where the adhesion amount increases.

Further, as an optimum example of the above-mentioned developer,
As the above-mentioned developer, the toner charge amount is 0 to -30% of the charge amount at the charging rising inflection point, preferably -5 to -20, as time passes while the toner circulates in the developing device.
% Of the charge amount at the charging rising inflection point with the passage of time within the time period during which the toner circulates in the developing device. Proposed is one having a characteristic that changes in the range of + 30%, preferably +5 to + 20%.

[0008]

According to the above construction, among the toner in the developer circulating in the developing device, the toner staying for a long time or the collected discharged toner is used preferentially over new toner on average. The developing ability does not decrease, and the toner does not scatter to pollute the inside and outside of the machine. That is, it operates as a toner image recording device having a long-life developing device and a developer.

[0009]

Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic diagram of a toner image recording apparatus to which the present invention is applied. In this example, an application example to an electrophotographic recording apparatus is shown as an example of the toner image recording apparatus. In addition to the electrophotographic recording device, an electrostatic recording device may be used in addition to the electrophotography as long as it is a device that forms an image by using a charged toner.

The embodiment of FIG. 1 is an embodiment of a laser printer, in which a photosensitive drum 1 is uniformly charged by a charger 2. The charged photosensitive drum 1 is irradiated with a laser beam 3 which is optically modulated with information to be recorded, and a charge latent image is formed. For example, when the image forming portion on the surface of the photosensitive drum 1 is exposed by the laser beam 3, the surface potential of the exposed portion disappears due to the effect of photoconductivity, and a charge latent image is obtained on the surface of the photosensitive drum 1. To be Photoconductor drum 1
The moving speed (circumferential speed) is 1 to 100 cm / s, and the charged surface potential is 300 to 1000V.

At the surface potential disappearing portion in the latent charge image,
The charged toner material in the developer conveyed by the developing roll 41 of the developing device 4 is electrostatically adhered and developed, and a toner image is formed on the photosensitive drum 1.

As the developer, only a two-component developer containing toner and a carrier (mainly a magnetic carrier) as main components, a one-component developer containing toner as a main component, and a vicinity of a developing region which is a modification of the two-component developer Any one of those having two components can be used. The developing device in FIG. 1 uses a two-component developer.

Next, the toner image formed on the photosensitive drum 1 is electrostatically transferred onto the recording paper 5 by the action of the transfer device 6 and then fixed by the fixing device (fixing roller) 7.
After the transfer, the toner remaining on the photoconductor drum 1 is removed by the cleaner 8, and then the residual charge is erased by the charge eliminating lamp 9, and the photoconductor drum 1 is subjected to the next image forming process.

On the other hand, the residual toner removed by the cleaner 8 is passed by the screw 10 and the return pipe 11 to
The toner is returned to the toner hopper 12 on the side of the developing device 4 and used again for development. The collected toner may be returned to the developer tank (on the developing device 4 side). When the toner is collected and reused, the residual toner is removed by the cleaner 8 and returned to the developing device side as described above, and the developing device 4 is used without using the cleaner 8.
Method, for example, the residual toner on the photosensitive drum 1 is lightly slid with a brush or the like to weaken the adhesive force, and the shape of the image is destroyed, and then the process proceeds to the next image forming step to develop the residual toner. The roll 41 may be slid and collected.

When the image forming process is repeated, the amount of toner in the two-component developer decreases, and this is detected, the toner feeder 13 is operated, and the toner is put into the developer from the toner hopper 12. . As a result, it is possible to control the toner density in the developer to be substantially constant, and it is possible to obtain image quality with stable image density. At this time, the toner fed from the toner hopper 12 is not mixed with the screw pair 43,
The impeller 42 uniformly mixes and stirs.

The operation of the developer in the developing device 4 used in such a printer will be described below with reference to FIGS. FIG. 2 is an example showing the relationship between the charge amount Q / M of the toner during the developing operation and the amount m of the developer toner attached to the charge latent image on the photosensitive drum 1. This characteristic is due to the speed of the photosensitive drum 1 being 250 mm / s, the latent image voltage being 400 V, and the two-component magnetic developer (toner concentration 3 wt%). The developer of FIG. 2 has a region A where the developing toner amount m decreases as the toner charge amount Q / M increases and a region B where the developing toner amount m increases.

When a two-component developer is used, it is preferably used in the area A. The reason is that the two-component developer is suitable for high-speed development, and in this case, it is preferable to set the Q / M to a relatively large value because it is necessary to suppress toner scattering. On the other hand, when a one-component developer is used, it is preferably used in the B region when the charge amount is small and in the A region when the charge amount is large.

FIG. 3 shows the time t when the toner is put into the two-component developer of the developing device 4 from the toner hopper 12.
And the toner charge amount Q / M with respect to
In the characteristic diagram of FIG. 3, the developing device has the same configuration as that illustrated in FIG. 1, and includes a developing roll (a magnetic developing roll having a diameter of 50 mm including a fixed magnet and a rotating sleeve), two screws, and an impeller. , Developer capacity about 2kg,
The developing roll peripheral speed is 500 mm / s. The developer is a two-component magnetic developer having a toner concentration of 2.5 wt% and is composed of a magnetite (Fl ₃ O ₄ ) carrier having an average particle size of about 100 μm and a toner having an average particle size of about 10 μm. Silicon oxide (SiO ₂ ) particles of about 30 nm are externally added.

The carrier has a substantially spherical shape, and the surface thereof has some wrinkle-like irregularities due to grain boundaries.
The surface is thinly coated with a modified silicone resin, and the volume resistance of the carrier is about 10 ⁸ Ωcm (the cell is lightly tapped and filled, and a voltage of 500 V / cm is applied).

On the other hand, the toner is obtained by kneading and pulverizing a toner containing a polyester resin, a carbon colorant, and a charge control material (azo-based chromium complex salt compound) as main components, and externally adding and dispersing silicon oxide particles. The charging polarity of the toner having such a configuration is negative.

In FIG. 3, the characteristics of (a) are as follows: carbon coloring material 8 wt%, charge control material 1 wt%, silicon oxide 0.3 w
This is the case when t% is used, and the characteristic (b) is that the charge control material is 3
wt% (others are the same as above), (C)
Characteristics of the charge control material is 0.02 wt% and silicon oxide is 0.
This is the case where it is set to 05 wt% (others are the same as the above-mentioned a). To measure the toner charge amount Q / M, the toner and the carrier are separately charged without mixing so as to form 3 to 5 layers in the developing device 4 tank, and then the developing device is operated to measure the toner amount with respect to time t. The charge amount Q / M was measured. The characteristics of (a), (b), and (c) change depending on the stirring strength of the developing device. This measurement can also be carried out as a model without using a developing device, by separately charging the toner and carrier into a glass bottle or a polyethylene container without mixing them and stirring them with a shaker. At this time, the shaking strength is calibrated in advance so as to be equivalent to the stirring in the developing device.

Considering the toner consumption status during the printing operation (during image formation), the adhered amount is 0.8 mg / cm.
^When it is ² , a print with an image density of D = 1.3 to 1.4 is obtained, but at this time, with A4 size, it is 0.5.
Since it is g / sheet, 0.021 mg / s is consumed at a printing speed of 50 sheets / minute and a printing density of 5%. Therefore, it takes 2857 seconds (s) and 285.
It will be 6s. In actual printing, there is a printing rate of 3 to 80% depending on the print content, and the toner consumption time assumed here is from t ₂ = 4762s to t ₁ = 17.
It is in the range of 8s.

In order to realize a recording apparatus which can obtain a stable image density for a long time even if the printing density is changed, the present invention is as follows. That is, in the t ₁ ~t ₂ hours, little change in the charge amount Q / M of the toner in the developing operation, as the residence time of in the developing device is viewed on average preferentially consumed from long , Try to prevent selective development. Therefore, after the toner is charged, the developer is quickly and uniformly mixed and stirred so that the toner charging rise time t ₃ is 5 to 20 s.
It is assumed that the toner is rapidly processed to a certain degree, and thereafter, a toner having a characteristic in which the longer the residence time is, the more easily the toner can be charged on average so that it can be easily developed.

The two-component developer of FIG. 3 is suitable for use in the area A of FIG. 2, but at this time, if Q / M is set to be small when the time t is large, it is apparent from FIG. As described above, the old toner having a long residence time is used, and if the charging rise time is fast, the amount of the new toner used can be relatively reduced. However, if the Q / M from t _{1 to} t ₂ changes significantly, the image density changes greatly, which is not practical. According to the experiment, the change is such that the charge amount of the toner is 0 to -30% of the charge amount at the charging rising inflection point, preferably -5 to-, within the time period during which the toner circulates in the developing device. In the case of (b), the change of 20% is preferable, and in the case of (b), the selective development can be prevented, but the image density change is large and not preferable. Further, in the case of using the toner in the area A as shown in (c), selective development occurs, and the image density decreases as the number of prints increases, resulting in a short developer life, which is inconvenient. there were.

The one which provides the above-mentioned two-component magnetic developer is a magnetic carrier having an average particle diameter of 30 to 200 μm.
m, preferably 50 to 130 μm, saturation magnetization density 10 to
100 emv / g, preferably 20 to 50 emv / g ferrite or magnetite is good, and the sphericity (minor axis / minor axis /
(Major axis) 0.7 or more spherical shape with 1-5 μm depth on the surface
It is particularly preferable that the concave portions are provided with a pitch of about 5 to 20 μm. Since it is almost spherical, it has good fluidity, and the uneven shape promotes microscopic mixing and stirring triboelectrification, and also dispersed organic or inorganic particles to be coated on the carrier surface to match triboelectrification characteristics with toner. This is because the organic coating material firmly adheres to the concave portions and can retain its function even when the coating material coated on the convex portions is worn.

The coating material is an organic material such as styrene, acryl, styrene-acryl, silicone, acryl-modified silicone, etc., in which fine particles of carbon, titanium oxide, silicone oxide, etc. are dispersed or a charge control agent is further added. The volume resistance of the carrier is 1
0 ⁶ to 10 ¹¹ Ωcm, dynamic resistance as a developer (resistance when measured in a state where the developer is magnetically attracted to the developing roll and rotated) is 10 ⁷ to 10 ¹² Ωcm, preferably 10 ⁸ It is preferably ¹⁰ to 10 ¹⁰ Ωcm.

Preferred toners will be described below.
As the toner resin, styrene, acryl, styrene-acryl, butadiene, or polyester can be applied, but the polyester resin is preferable because it has high toughness and has a large resistance to the load caused by stirring and mixing in the developing device. Toner is a colorant (5-15 wt.
%), Charge control agents (1 to 5 wt%), and other internal additives,
It is made by kneading and pulverizing, and then an external additive (0.01 to 1 wt%) such as a fluidity modifier and a charge control agent is externally added thereto. The average particle size is 5 to 12 μm, and the volume resistance is 10 ¹⁰ to 10 ¹⁶ Ω.
cm Preferably 10 ¹¹ to 10 ¹⁴ Ωcm (100 to 200
(Pressure of kg / cm ² is applied and measured at 100 V / mm)
Is desirable, and it is desirable that the voltage dependency is such that the resistance value decreases when the voltage is high. This is because at this time, the charging characteristic having a small toner concentration dependency described in FIG. 7 is obtained.

In order to obtain the characteristics shown in FIG. 3A, the behaviors of the charge control agent and the external additive, which are internal additives, are important, as will be described later with reference to FIGS. According to the experiment, good results were obtained by using two kinds of control agents having different properties as the control agents to be internally added. For example, in order to use negatively charged toner,
1 to 3 wt% of a negative charge control agent (azo type chromium complex salt compound or salicylic acid type complex salt compound) as a main charge control agent and 0.05 to 0.5 wt% of an auxiliary charge control agent to a styrene / acrylic or polyester resin. Good results were obtained when a positive charge control agent (such as a fatty acid modified nigrosine dye or a quaternary ammonium salt compound) was used in combination. At this time, when the main charge control agent was too much, the tendency (b) was shown, and when only the main charge control agent was too little, the tendency (c) was shown.

As described above, the two-component developer for obtaining the characteristic (a) is described as the preferred one of the present invention in FIG. 3, but as described above, the charge amount is 3 to 1
A one-component developer using a toner having a low charge amount of about 0 μC / g is operated in the region of FIG. 2B, and the preferable charging property of the toner is as shown in FIG. The toner charge amount is 0 to 30%, and more preferably 5 to 20% of the value of the charging rising inflection point (t ₃ ) within the period of circulation within the time.

FIG. 4 shows an embodiment showing more preferable characteristics when a developer having the characteristics shown in FIG. 3A is used for a long period of time, which is printed by using the printer described in FIG. The developer capacity is 2 kg. This developer is composed of the same magnetite carrier and polyester toner as in FIG. In FIG. 4, q ₁ is the charge amount of the toner that has been developed and adhered to the surface of the photosensitive drum 1, q ₂ is the charge amount of the developer in the developing device, and printing was performed at a toner concentration of 2.5 wt%. As shown in the figure, the high image density D can be maintained for 1 million prints.
At this time, the periphery of the developing device 4 and the periphery of the photosensitive drum 1 were observed, but the toner scattering was extremely small. The reason why the decrease in the image density D is small is that q ₁ is substantially constant, and the reason why the toner scattering is small is that there is no decrease in q _{2 and} the q ₂ is gradually increasing. According to some experiments, the permissible change in q _{2 that} can suppress the toner scattering for a long period of time with a small decrease in image density is -10 to 30%, preferably 5 to 20%.
The reason why q ₂ can be gradually increased without decreasing over a long period of time is that the developer used in the developer of the present invention is such that the coating material coated on the carrier surface is gradually removed from the protrusions This is because the toner component does not adhere to the carrier. That is, the charge amount of the toner on the carrier before the surface coating is larger than that of the carrier after the coating, and gradually increases by scraping a part of the coating material. The slight decrease in image density in FIG. 4 can be compensated by increasing the toner density by about 0.5 wt% with use. At this time, the toner scattering hardly increased. This is because, as will be described later with reference to FIG. 7, in the present developer, q ₂ is less decreased even if the toner concentration is increased.

In FIG. 4, more preferable ones are those in which the changes in q ₁ and q ₂ at the initial stage are smaller. This initial change is due to water-soluble ions adhering to the carrier surface,
This is because the foreign matter removing effect and the surface coating material that can be easily scraped (a convex portion or a material having a weak adhesive force) can be removed in the initial stage. Therefore, removing them from the beginning gives better results. For example, water-soluble ions (Na + ions,
K + ions, Ca + ions, Mg + ions, Cl @ - ion, CO ₃ - ions) or also the elution is 20ppm preferably 5ppm or less even if the carrier of very small (50g eluting with water 50 cm ³⁾ those by washing with water By applying a mechanical load to the carrier, scraping off the weakly adhering substances on the surface, and washing it or blowing it off with an air stream to remove it, the initial change amount is 20%. It can be suppressed to about 10% or less, and a preferable result can be given.

As a carrier, particularly magnetite (Fe
It was mentioned above that ₃ O ₄ ) is particularly preferable, because it is possible to form a substantially spherical shape having many wrinkled concave portions on the surface, and since it has high mechanical strength and is not easily worn or broken. On the other hand, ferrite containing Cu, Mn, Zn, Ni, Ba and the like has a mechanical strength slightly weaker than that of magnetite, and therefore has little tolerance to the stirring strength of the developing device and the conveying speed (high speed development). In addition, the Fe-based carrier has a large magnetizing force, which causes a large load and is inconvenient.

FIG. 5 schematically shows that the toner of the present invention (old toner) 15 used for a long time in the developing tank without selective development is used before new toner 16. It is a thing. The surface-coated carrier 14 and the old toner 15 and new toner 16 contact each other,
Although the toner is charged by rubbing, the amount of charge of the old toner 15 decreases with the passage of time, and the new toner 16 has a value near the maximum value in FIG. Then, since the new toner 16 having a large amount of electric charge has a large adhesive force to the carrier 14, the new toner 16 adheres to the carrier while the positional relationship between the new toner and the old toner is exchanged. Therefore, in combination with the fact that the old toner has a smaller charge amount, the old toner is more likely to be transferred to the charge latent image on the photosensitive drum, and the toner is preferentially developed on average.

When the toner is charged in the developer, at least two kinds having different polarities are added as the charge control agent in order to accelerate the rise of the charge of the toner and prevent the value from becoming excessive. Good to do. As a result, the charging speed is increased by the friction between the toner particles and the saturated charge amount is suppressed by the opposite polarity control agent. Further, in order to have a characteristic that the charged charge amount gradually decreases as shown in FIG. 3A, the external additive 18 is gradually buried in the toner 17 as shown in FIG. Is good. For this purpose, the diameter of the external additive such as SiO ₂ or TiO ₂ should be 20
It is good to set it to -50 nm.

FIG. 7 shows a relationship between the toner charge amount and the toner charge amount in the two-component developer suitable for the present invention. The characteristic conventionally known as a two-component developer is something like B shown by the dotted line, and the toner concentration dependence is largely inversely proportional.

On the other hand, the developer suitable for use in the present invention has a small toner concentration dependency as in A (even if the toner concentration is doubled, the change in charge amount is 30% or less, preferably 20% or less). . A is the same as that described in FIG. 3A, and B shown here is an example in which the same carrier is used and one kind of charge control agent is added as a toner and no external additive is used. Is. If the toner density dependency is small, the toner density range in which the image density can be stably obtained becomes wider,
Further, damage such as toner scattering does not easily occur, and a developing device having a small developer capacity (0.2 to 2 kg) can be realized, and toner concentration can be easily controlled. This is because the toner charge rises quickly and the amount of charge is almost constant.Therefore, even if the toner concentration changes, the development adhesion performance changes, or when the toner is replenished or the toner concentration increases, the toner is This is because the particles tend to scatter, and the fluidity and bulk density of the developer are less likely to be affected by the amount of charge. Further, preferably,
Since the developer having the characteristics as shown in FIG. 7A is nothing but the excellent charging stability of the toner, it is stable and hardly affected by temperature and humidity.

As for the preferable developing characteristics as described above, the agitating and mixing performance of the developing device used together with the developer as described above must be a certain level or more. When a two-component developer is used, the developer is agitated, mixed, and circulated in the configuration shown in the developing device 14 in FIG. 1 so that the replenishment toner is quickly charged and stays longer than new toner. Is developed first, and the carrier surface coating material can be gradually scraped off without fixing the toner component to the carrier surface. For example, as will be described later with reference to FIG. 8, a fin 45 is attached to the screw pair 44 to apply a shearing force to the developer and the temperature of the developer tank is about 10 ° C., preferably 15 ° C., from the glass transition point of the toner.
It is optimal to use at a temperature lower than ° C.

Even when a one-component developer is used as the developer, the developing toner tank and the replenishing toner tank are substantially separated from each other, and the toner is circulated uniformly in the developing toner tank. Development can be further suppressed.

FIG. 8 shows an example of a suitable structure of the screw of the screw pair 43 preferable for use in the developing device 4 of FIG. By installing the fins 45 on the screw 44, not only the developer is transferred in the axial direction, but also the transfer force and the shearing force in the perpendicular direction are applied to accelerate the rise of the toner charge and microscopic stirring and mixing of the developer. can do.

[0040]

According to the present invention, since the charge amount of the developer toner during the developing operation is changed in the direction in which the amount of the deposited toner increases with use, selective development can be prevented and old toner can be removed. Since the toner is used preferentially on average, a long-life developer and a powder toner image recording apparatus capable of obtaining stable image quality can be realized.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration example of a laser printer to which the present invention is applied.

FIG. 2 is a diagram showing a relationship between a charge amount of toner and a development adhesion amount.

FIG. 3 is a diagram showing a time transition of a toner charge amount.

FIG. 4 is a diagram showing changes in the charge amount of toner and image density.

FIG. 5 is a schematic diagram of a developer and a toner.

FIG. 6 is a schematic diagram of a developer and a toner.

FIG. 7 is a diagram showing a relationship between a toner charge amount and toner concentration.

FIG. 8 is a view showing an example of a screw installed inside the developing device.

[Explanation of symbols]

1 ... Photosensitive drum, 2 ... Charger, 3 ... Laser beam, 4
... developing device, 8 ... cleaner, 11 ... toner return pipe.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location G03G 9/08 9/10 15/06 101 21/10 G03G 21/00 326 (72) Inventor West East Yosuke 1060 Takeda, Hitachinaka-shi, Ibaraki Hitachi Koki Co., Ltd. (72) Inventor Yasuo Kikuchi 1060 Takeda, Hitachinaka-shi, Ibaraki Hitachi Koki Co., Ltd. (72) Junji Kobayashi 1060 Takeda, Hitachinaka-shi, Ibaraki Hitachi Koki Co., Ltd. (72) Inventor Katsuhiro Akinaga 1060 Takeda, Hitachinaka City, Ibaraki Prefecture Hitachi Koki Co., Ltd. (72) Yoshitaka Fujinuma 1060 Takeda, Hitachinaka City, Ibaraki Hitachi Koki Co., Ltd.

Claims (9)

[Claims] 1. In a toner image recording apparatus for developing a charge latent image with a charged colored toner, the operating point of the toner charge amount is in a region where the toner adhesion amount to the photosensitive drum decreases as the charge amount increases. Occasionally, a developer with a characteristic that the toner charge amount gradually decreases as the used toner ages, or the operating point of the toner charge amount is such that as the charge amount increases, the amount of toner attached to the photosensitive drum increases. The toner image recording apparatus is characterized in that a developer having a characteristic that the toner charge amount gradually increases as the used toner ages when the toner is in the area. 2. In the developer having the above characteristics, the charge amount of the toner is 0 to -30% of the charge amount at the charging rising inflection point with the passage of time during which the toner circulates in the developing device, preferably − In the developer having the above characteristics, the charge amount of the toner is 0 to + 30% of the charge amount at the charging inflection point as the toner circulates in the developing device. Is +5 to +2
The toner image recording apparatus according to claim 1, wherein the toner image recording apparatus changes by 0%. 3. The method according to claim 1, wherein after the developed toner image is transferred onto the recording paper, the residual toner on the charge latent image forming medium is collected and returned to the developing device for reuse. The toner image recording apparatus according to claim 2. 4. A developer containing a charged colored toner for developing a charge latent image, wherein the operating point of the charge amount of the toner is in a region where the toner adhesion amount to the photosensitive drum decreases as the charge amount increases. Is circulated in the developing device as time passes,
Toner charge is charged from 0 to-
A developer characterized by having characteristics of changing in a range of 30%, preferably -5 to -20%. 5. A developer containing a charged colored toner for developing a charge latent image, wherein the operating point of the charge amount of the toner is in a region in which the toner adhesion amount to the photosensitive drum increases as the charge amount increases. Is circulated in the developing device as time passes,
0 to + of the charge amount at the inflection point
A developer having a characteristic of changing in a range of 30%, preferably +5 to + 20%. 6. A two-component developer comprising a carrier and a colored toner as main components, the total charge amount of which gradually increases with time of use, and the carrier is a core material coated with a coating material. 6. The developer according to claim 4, wherein the toner charge amount is larger than that of the core material alone. 7. The developer according to claim 4, wherein both the positive charge control agent and the negative charge control agent are used as the charge control agent contained in the toner. 8. A two-component developer comprising a carrier and a colored toner as main components, which has the property of developing in a region where the toner concentration dependency of the toner charge amount is small. The developer according to claim 1. 9. The developer according to claim 4, wherein the external additive added to the toner has a characteristic of being embedded in the toner while circulating in the developing device. .