JP3191074B2 - One-component developer and image forming method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a developer for developing an electrostatic latent image in electrophotography, electrostatic recording, electrostatic printing, and the like.

Further, the present invention is used in a system having a step of collecting a transfer residual developer on an image carrier and supplying the developer to a developing device in an electrophotographic method, an electrostatic recording method, an electrostatic printing method, or the like. The present invention relates to a developer for visualizing a latent electrostatic image.

Further, the present invention relates to an image forming method including a step of collecting a transfer residual developer on an image carrier and supplying the developer to a developing device in an electrophotographic method, an electrostatic recording method, an electrostatic printing method, or the like. .

[0004]

2. Description of the Related Art Conventionally, as an electrophotographic method, US Pat.
No. 297691, JP-B-42-23910 (U.S. Pat. No. 3,666,363) and JP-B-43-43.
A number of methods are known as described in, for example, Japanese Patent No. 24748 (U.S. Pat. No. 4,707,361). In general, a photoconductive substance is used to electrically connect a photoconductor to a photoreceptor by various means. Forming a latent image, developing the latent image with toner, and then transferring the toner image to a transfer material, and fixing by heating, pressing, heating / pressing, or solvent vapor to obtain a copy. It is.

In the above-described transfer step, various methods and apparatuses have been developed. However, there are still a few developers that cannot be transferred onto the photosensitive member, ie, untransferred developers. This untransferred developer is cleaned by various methods and stored in the copying machine main body.

In recent years, there has been a demand for a small, high-speed copying machine capable of copying many sheets while maintaining high image quality. However, in the current high-speed copier,
Miniaturization is not necessarily achieved. One of the factors is a space after collecting the untransferred developer. On the other hand, the treatment of the recovered untransferred developer is a very serious problem with respect to the current environmental problems.
That is, by supplying the recovered untransferred developer to the developing device, the above-mentioned problems can be overcome, and a small-sized, high-speed copying machine adapted to environmental problems can be achieved. Further, the number of copies that can be made with respect to the developer to be replenished is increased, so that the per copy cost is reduced and the cost is high.

Until now, attempts have been made to supply the recovered untransferred developer to a developing device and use it in a developing step. However, as this process is introduced and copying of a large number of sheets is repeated, there are various problems such as, for example, deterioration of image quality and reduction of image density, and it becomes difficult to provide a stable image for a long time. There is a problem that.

In Japanese Patent Application Laid-Open No. 2-157765,
By regulating the particle size distribution, with the intention of solving the above problems,
Two-component developers have been proposed.

[0009] However, a two-component developer can provide a high-quality image relatively stably at the initial stage, but on the other hand, it suffers from deterioration of the carrier and a change in the mixing ratio of the toner and the carrier, so that a long-term development is impossible. There is a problem of lack of durability.

In order to avoid such drawbacks, various developing methods using a one-component developer consisting of toner alone have been proposed, but many of them are excellent in methods using a developer consisting of magnetic toner particles. .

Conventionally, as a developing method using a one-component magnetic toner, a developing method using a conductive magnetic toner disclosed in US Pat. No. 3,909,258 is known. In this method, a conductive magnetic toner is supported on a cylindrical conductive toner carrier (hereinafter, referred to as a "sleeve") having magnetism therein, and is contacted with an electrostatic latent image for development. At this time, in the developing section, a conductive path is formed by toner particles between the surface of the latent image holding member and the surface of the sleeve,
Electric charges are guided to the toner particles from the sleeve via the conductive path, and the toner particles adhere to the image portion by the Coulomb force between the electrostatic latent image and the image portion and are developed. The developing method using the conductive magnetic toner is an excellent method that avoids the problems associated with the conventional two-component developing method. However, since the toner is conductive, the toner image on the latent image holding member is supported by the final image. There is a problem that it is difficult to transfer electrostatically to a member (for example, plain paper) using an electric field.

However, Japanese Patent Application Laid-Open No. 55-18656 proposes a new developing method which eliminates the above-mentioned problems. This involves applying a very thin coating of magnetic toner on a sleeve, triboelectrically charging it, and then developing it very close to the electrostatic latent image. This method increases the chance of contact between the sleeve and the toner by applying the magnetic toner on the sleeve in a very thin and close proximity, enables sufficient triboelectric charging, supports the toner by magnetic force, and The toner particles are relatively moved to disperse the toner particles from each other and sufficiently rub against the sleeve, and the toner is supported by a magnetic force and is developed by facing the toner without contacting the electrostatic latent image. Thus, an excellent image can be obtained by preventing such a phenomenon (hereinafter, this developing method is referred to as "jumping development").

By using such a developing method,
The problem of lack of long-term durability with a two-component developer can be solved. Further, as a feature of the developing device used in such a developing method, a very small and simple configuration can be adopted. This makes it possible to reduce the size of the copying machine body in addition to using the transfer residual developer again in the developing step. However, when using jumping development, which simplifies the construction of the developing device, collecting the remaining transfer developer, and supplying the recovered developer for use in the development process, a larger number of copies or copies than the conventional developer are required. In addition, it is indispensable to maintain excellent development characteristics even when the environment fluctuates, and for that purpose, stable charge controllability is required.

That is, a latent image on the latent image carrier is developed and transferred, and a recovered product obtained by cleaning the transferred latent image carrier is supplied to a developing device to be used as a component in a system used in a developing process. When using a developer, the following issues are important. Problem (A): To uniformly coat a one-component developer on a developer carrier. Problem (B): To efficiently and uniformly triboelectrically charge a one-component developer.

In the problem (A), as a method of forming a coating layer of the developer on the developer carrying member, there is a method of using a coating blade at an outlet of the developer container. In the case of a one-component magnetic toner, for example, a blade made of a magnetic material is provided at a position facing one magnetic pole of a fixed magnet contained in a developer carrier, and development is performed along a magnetic force line between the magnetic pole and the magnetic material blade. The developer is spiked and cut at the edge of the blade tip to control the thickness of the coating layer of the developer by using the action of magnetic force.
No. 43034).

Further, with respect to the problem (A), a method of uniformly coating a one-component developer on a developer carrier is disclosed in
66455. The developing device described in the official gazette uses a developer carrier whose surface has a rough surface with irregularities in an irregular shape by sandblasting with irregular particles. This is a developing device that can maintain a good coating state over a long period of time without uniform unevenness on the surface. The developer carrier has a mode in which countless fine cuts or projections are formed in random directions over the entire surface.

However, in a developing device using a developer carrier having such a specific surface condition, depending on a one-component developer to be applied, deterioration of developability such as fog and density reduction is observed. This is caused by the fact that poorly charged toner particles are generated in the one-component developer and the charge amount of the developer layer is reduced. Further, tailing, scattering, and instability of thin line reproduction may occur.

On the other hand, with respect to the problem (B), a method of making the surface of the developer carrier smoother has been proposed as a method for improving the ability of the developer carrier to provide triboelectric charging to a one-component developer. . However, in such a method, it has been found that the applied layer of the one-component developer may become non-uniform, resulting in uneven visible images and failing to obtain good images.

A method for simultaneously achieving both the problem (A) and the problem (B) satisfactorily has been proposed in the specification of Japanese Patent Application No. 63-46882 (corresponding to European Patent Application No. 0331425). In this developing method, a developer carrier is used.
The coating layer of the developer can be uniformly formed by blasting the surface with the fixed particles and a one-component developer having a specific particle size distribution.

However, even when a developer carrier having a specific surface as described above and a one-component developer having a specific particle size distribution are used, the surface of the developer carrier gradually becomes longer due to use over a long period of time. The surface of the developer is changed to a smooth surface, and the effect of the blast treatment with the initial stable particles is not obtained, and the applied layer of the developer becomes an uneven layer, resulting in uneven application of the developer on the developer carrier. As a result, uneven fog due to coating unevenness occurs in the background area having a low image density. This problem is more likely to occur at low humidity, especially at room temperature and extremely low humidity.

On the other hand, in a high-speed copying machine, improvement of reliability is a major issue, and stable high-quality images are required to be maintained even after long-term durability. There is a need for a one-component developer that can provide a stable image even in the above condition.

In general, in the one-component developing system, when image formation is repeated, toner particles having a small particle diameter adhere to the surface of the developer carrying member due to the mirroring force due to the high charge amount,
Inhibits triboelectric charging of other toner particles. As a result, toner particles that do not have a sufficient amount of charge may increase, causing a decrease in density. Such a phenomenon is particularly likely to occur in low humidity.

Such a phenomenon is promoted when the toner on the developer carrying member is not consumed (for example, an image white background), and appears as a decrease in image density. On the other hand, in such a state, as the toner on the developer carrier is consumed (for example, an image black portion), this phenomenon is alleviated, and the density gradually recovers.

Therefore, when the latent image is developed in the presence of the consuming portion (corresponding to the image portion) where the toner is consumed by the developer carrier and the non-consuming portion (corresponding to the non-image portion) where the toner is not consumed. Then, a difference in density (high density in the consuming portion, low density in the non-consuming portion) occurs on the toner image.

Such a phenomenon is hereinafter referred to as "developer carrier memory". Considering the mechanism of formation, this developer carrier memory is eliminated by toner consumption on the developer carrier. The developer carrier memory is reduced every circumference of one rotation of the developer carrier. Accordingly, when the memory of the developer carrier is light, the memory on the developed image disappears after one rotation, but when the memory is heavy, the memory may appear repeatedly.

According to the study by the present inventors, the developer carrying member blasted with the regular particles is superior in the toner charging ability to the toner carrying member blasted with the irregular particles. This is advantageous for sufficiently exhibiting the charging ability of the toner. However, in some cases, the toner may be overcharged, which tends to cause the above-described phenomenon.

[0027]

SUMMARY OF THE INVENTION It is an object of the present invention to develop and transfer a latent image on a latent image carrier using a developer and to clean a recovered image obtained by cleaning the latent image carrier after the transfer. It is an object of the present invention to provide a one-component developer and an image forming method which solve the above-mentioned problems in a system which is supplied to a developing device and used in a developing process.

An object of the present invention is to develop and transfer a latent image on a latent image carrier using a developer, and supply a collected product obtained by cleaning the latent image carrier after transfer to a developing device. It is an object of the present invention to provide a one-component developer and an image forming method capable of maintaining a high image density for a long time and stably obtaining an image without background fog in a system used in a developing process.

An object of the present invention is to develop and transfer a latent image on a latent image carrier using a developer, and supply a collected product obtained by cleaning the latent image carrier after transfer to a developing device. It is an object of the present invention to provide a one-component developer and an image forming method which can stably obtain a high-density image free from background fog even under high humidity in a system used in a developing process.

[0030]

SUMMARY OF THE INVENTION The present invention, which has been made to achieve the above object , has a gap between the surface of the latent image carrier and the space.
Component development on the surface of the developer carrier
Forming a developer layer with a developer, and providing the latent image carrier with the developer
DC and AC electric fields in the development area, which is the closest part to the carrier
Forming the one-component developer onto the developer.
By flying from the surface of the body, developing the latent image on said image bearing member
To form a toner image, and transfer the toner image on the latent image carrier.
Transferred to Utsushizai, one-component developer latent recovery product obtained by cleaning the image bearing member surface is supplied to the developing device used in a system for use in the development step after the transfer, and further the
An image forming method employing the system, the one-component current <br/> image agents are contained and one adult <br/> component toner and inorganic fine powder you containing at least a binder resin and a colorant , The one-component toner
Indicates that the weight average diameter D4 is 4 to 11 μm and the weight average
The ratio (D4 / D1) of the diameter D4 to the average length diameter D1 is 1.0
1-2, and the inorganic fine powder has a weight average diameter D4 of 0.1.
6 to 5 μm, the average length diameter D1 is 0.5 to 4 μm, and the ratio of the weight average diameter D4 to the average length diameter D1 ( D4 /
D1 ) is 2.4 or less, and the addition amount of the inorganic fine powder is 0.3 to 5% by weight based on the one-component toner.

The one-component toner according to the present invention has a weight average diameter D4 of 0.6 to 5 μm and a length average diameter D1 of 0.5.
When an inorganic fine powder having a thickness of about 4 μm is added, the inorganic fine powder is selectively applied in the vicinity of the sleeve surface, and a very thin layer of the inorganic fine powder is formed. A layer is formed.

Therefore, since the one-component toner does not come into direct contact with the surface of the sleeve, it is possible to prevent the one-component toner from being fixed on the surface of the sleeve due to the reflection force. No unevenness occurs.

In the present invention, the inorganic fine powder to be added to the one-component toner is preferably an inorganic fine powder having a charge polarity opposite to that of the one-component toner and having a small charge amount. The inorganic fine powder separates,
The effect of increasing the charge amount of the one-component toner can be provided.

A system in which a latent image on a latent image carrier is developed and transferred using a developer, and a recovered product obtained by cleaning the transferred latent image carrier is supplied to a developing device and used in a developing process. In the above, the inorganic fine powder opposite in charge to the one-component toner described above is separated from the one-component toner by a developing bias during development, but the separated inorganic fine powder flies to a non-image portion on the latent image carrier. However, some are collected in the cleaner without being transferred.

The proportion of the inorganic fine powder in the collected cleaner tends to increase as compared with the proportion of the inorganic fine powder contained in the initial developer.

Therefore, when the amount of the inorganic fine powder in the initial developer is large, the amount of the inorganic fine powder in the collected cleaner is also large. If the collected material in the cleaner is used again in the developing step in this state, poor charging occurs between the collected developer and a new developer to be replenished, causing a reduction in image density. In addition, the load on the cleaner gradually increases, and cleaning failure may occur.

Conversely, if the amount of the inorganic fine powder contained in the initial developer is too small, it is difficult to prevent the above-mentioned uneven coating of the sleeve and increase the charge amount of the one-component toner. Become.

That is, as the inorganic fine powder in the one-component developer used in the system according to the present invention, a small amount of the inorganic fine powder can be used.
It is necessary to have the effect of preventing sleeve coating unevenness and increasing the charge amount of the one-component toner.

As a result of intensive studies on this point, the present inventors have obtained new knowledge on the relationship between the one-component toner and the inorganic fine powder.

That is, for a toner having a certain particle size, an inorganic fine powder having a particle size within a certain range has a capability of significantly increasing the charge amount of the toner. Specifically, the weight average diameter of the one-component toner is 4 to 11 μm, the weight average diameter D4 is 0.6 to 5 μm, and the length average diameter D1 is 0.5 to 4 μm for the one-component toner. And D4 / D
1 to 2.4 or less of 0.3 to 5
By containing the component in wt%, the charge amount of the one-component toner can be increased, and even a one-component toner having a high charge amount can be prevented from sticking to the surface of the sleeve, and a cleaning failure can also be prevented. Further, in a system in which a latent image on the latent image carrier is developed and transferred using a developer, and a collected product obtained by cleaning the transferred latent image carrier is supplied to a developing device and used in a developing process. In addition, charging failure between the recovered developer and the new developer to be supplied can be prevented.

The particle diameter of the one-component toner is preferably 4 to 11 μm in terms of image characteristics. If it exceeds 11 μm, particles having a coarse particle diameter relatively increase in the one-component developer, and the image density decreases under long-term durability and high humidity. If it is less than 4 μm, background fog is reduced. This may cause bad effects such as poor cleaning or poor cleaning. Further, the productivity of the toner becomes very poor, leading to an increase in cost.

It is added to the one-component toner having a weight average diameter of 4 to 11 μm, and prevents the sleeve coating unevenness with a small addition amount.
The inorganic fine powder having the function of increasing the charge amount of the one-component toner has a weight average diameter D4 of 0.6 to 5 μm, a length average diameter D1 of 0.5 to 4 μm, and D4 / D
It is preferable to add 0.3 to 5 wt% of a compound having a ratio of 1 or less to 2.4.

When an inorganic fine powder having a weight average diameter D4 of more than 5 μm is used, the chargeability of the one-component toner is improved to some extent, but because of the large size, the inorganic fine powder does not fly on the latent image bearing member. It accumulates in the developing device, and the amount of inorganic fine powder in the developing device increases. This causes a phenomenon that the charge of the one-component toner received from the charging member such as the sleeve is inhibited, and the image density is reduced.

Conversely, when the weight average diameter D4 is smaller than 0.6 μm, the charge amount of the toner cannot be efficiently increased with respect to the particle diameter of the one-component toner used in the present invention.

When D4 / D1 is larger than 2.4, the particle size distribution becomes too wide, and the particles having too fine or too coarse particles are included, which causes the above-mentioned adverse effects. Not preferred.

As the one-component toner to which the inorganic fine powder having the above-mentioned particle size distribution is added, those having a weight average diameter / length average diameter in the range of 1.01 to 2 are efficiently affected by the effect of increasing the charge amount. Is very preferred. An increase in the weight average diameter / length average diameter of the one-component toner means that the particle size distribution of the toner is widened, that is, the proportion of fine or coarse particles is increased. When the weight average diameter / length average diameter of the one-component toner is larger than 2, the fine particle toner and the coarse particle toner contained in the developer may be electrostatically or magnetically applied to the developer carrier. It is restrained, does not easily fly on the latent image carrier, and tends to remain on the developer carrier. However, due to the developing bias, the inorganic fine powder separated from the toner having a fine particle diameter or the toner having a coarse particle diameter flies on the latent image carrier, so that the ratio of the inorganic fine powder in the developer collected by the cleaner increases.
The use of such a recovered developer in the developing step is the same as the case where the amount of the inorganic fine powder in the initial developer is large, as described above. The proportion of the inorganic fine powder significantly increases. This causes charging failure between the collected developer and a new developer to be replenished, and causes a decrease in image density, which is not preferable.

The weight average diameter D4 added to the one-component toner having a weight average diameter of 4 to 11 μm is 0.6 to 5 μm,
When the content of the inorganic fine powder having a length average diameter D1 of 0.5 to 4 μm and a ratio of D4 / D1 of 2.4 or less exceeds 5 wt% with respect to the one-component toner, the collected product of the cleaner is developed again. In the long-term durability of the system used for the above, the amount of the inorganic fine powder in the cleaner increases, the load on the cleaner gradually increases, and cleaning failure occurs. On the other hand, if the content is less than 0.3 wt%, the effect of preventing the sleeve coating unevenness and increasing the charge amount of the one-component toner is not sufficiently provided.

The particle size distribution of the one-component toner and the inorganic fine powder having the opposite charge to the one-component toner can be measured by various methods. In the present invention, the measurement was performed using a Coulter counter multisizer.

That is, as a measuring device, a Coulter counter Multisizer II type (manufactured by Coulter) was used, and an interface (manufactured by Nikkaki) for outputting the number distribution and volume distribution and a PC 9801 (manufactured by NEC) were connected. Use a special grade or primary grade sodium chloride for 1
% NaCl aqueous solution is prepared. As a measuring method, a surfactant, preferably an alkylbenzene sulfonate, is used as a dispersant in 100 to 150 ml of the electrolytic aqueous solution.
Add 5 ml, and further add 2-20 mg of the measurement sample.
The electrolytic solution in which the sample is suspended is subjected to dispersion treatment for about 1 to 3 minutes with an ultrasonic disperser, and a multi-sizer type II of the Coulter counter uses a 100 μm aperture when measuring the toner particle size as an aperture. When the particle diameter of the inorganic fine powder is measured, it is measured using a 13 μm aperture. The volume and the number of the toner and the inorganic fine powder were measured, and the volume distribution and the number distribution were calculated. Then, the weight-based weight average diameter according to the present invention was determined from the volume distribution, and the number-based length average diameter was determined from the number distribution.

For reference, a method for measuring the charge amount of the inorganic fine powder is described below.

0.2 g of inorganic fine powder left overnight in an environment of 23.5 ° C. and 60% RH, and 9.8 g of a positively chargeable toner and a negatively chargeable toner having a main particle size of 200 to 300 mesh. Are weighed accurately under the above-mentioned environment, and about 5
0c. c. Mix thoroughly (hold in hand and shake up and down approximately 125 times for about 50 seconds) in a jar with a polyethylene lid having a volume of.

Next, as shown in FIG. 3, about 2.0 g of the mixture is placed in a metal measuring container 32 having a screen 33 of 400 mesh at the bottom, and a metal lid 34 is provided. At this time, the weight of the entire measurement container 32 is weighed and defined as W ₁ (g). next,
In the suction device 31 (the part in contact with the measurement container 32 is at least an insulator), the air is sucked from the suction port 37 and the air volume control valve 36
Is adjusted to bring the pressure of the vacuum gauge 35 to 250 mmHg.
In this state, sufficient suction is performed for 5 minutes to remove the inorganic fine powder by suction. The potential of the electrometer 39 at this time is set to V (volt). Here, 38 is a capacitor whose capacity is C (μF).
And Also, the weight of the whole measurement container after suction is weighed and W ₂
(G). The charge amount (μc / g) of this inorganic fine powder is calculated as in the following equation.

Charge amount = −CV / (W ₁ −W ₂ ) When the toner used in the present invention is, for example, a one-component magnetic toner, the following components can be used.

Examples of the binder resin include, for example, a homopolymer or copolymer of a vinyl monomer shown below: styrene;
o-methylstyrene, m-methylstyrene, p-methylstyrene, p-methoxystyrene, p-phenylstyrene, p-chlorostyrene, 3,4-dichlorostyrene,
p-ethylstyrene, 2,4-dimethylstyrene, p-
n-butylstyrene, p-tert-butylstyrene,
Derivatives of styrene such as pn-hexylstyrene, pn-octylstyrene, pn-nonylstyrene, pn-decylstyrene, pn-dodecylstyrene; ethylene such as ethylene, propylene, butylene and isobutylene Unsaturated polyolefins such as butadiene; vinyl halides such as vinyl chloride, vinylidene chloride, vinyl bromide, and vinyl fluoride; vinyl esters such as vinyl acetate, vinyl propionate and vinyl benzoate; Methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, phenyl methacrylate, dimethyl methacrylate Methacrylic esters such as methylaminoethyl and diethylaminoethyl methacrylate; methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, propyl acrylate, n-octyl acrylate, dodecyl acrylate, ethylhexyl acrylate, acrylic Acrylic esters such as stearyl acid, 2-chloroethyl acrylate and phenyl acrylate; vinyl ethers such as vinyl methyl ether, vinyl ethyl ether and vinyl isobutyl ether; vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone and methyl isopropenyl ketone , N-vinylpyrrole, N-vinylcarbazole, N
N- such as vinylindole and N-vinylpyrrolidone
Vinyl compounds; vinyl naphthalenes; acrylic acid derivatives such as acrylonitrile, methacrylonitrile, acrylamide or methacrylic acid derivatives; acrylic acid;
Vinyl compound derivatives having a carboxyl group such as methacrylic acid, maleic acid and fumaric acid; half esters such as maleic acid half ester and fumaric acid half ester; maleic anhydride, maleic acid ester and fumaric acid ester derivatives.

Further, polyester, polyurethane, epoxy resin, polyvinyl butyral, rosin, modified rosin, terpene resin, phenol resin, aliphatic or alicyclic hydrocarbon resin, aromatic petroleum resin, haloparaffin,
Paraffin wax and the like. These can be used alone or in combination.

Of these, styrene resins, acrylic resins, and polyester resins are particularly preferably used as the binder resin in consideration of the developing characteristics of the toner.

The above-mentioned binder resin is a vinyl polymer, a vinyl copolymer or a mixture thereof cross-linked with a cross-linking agent as exemplified below in consideration of the offset resistance as a toner. It is more preferred that there be.

Aromatic divinyl compounds (eg, divinylbenzene, divinylnaphthalene, etc.); diacrylate compounds linked by alkyl chains (eg, ethylene glycol diacrylate, 1,3-butylene glycol diacrylate, 1,4-butane) Diol diacrylate,
1,5-pentanediol diacrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate) and those obtained by replacing the acrylate of the above compound with methacrylate; diacrylate peeled with an alkyl chain containing an ether bond Compounds (eg, diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol # 400 diacrylate, polyethylene glycol # 600 diacrylate, dipropylene glycol diacrylate) and acrylates of the above compounds are converted to methacrylate. Substituted diacrylate compounds linked by a chain containing an aromatic group and an ether bond [for example, polyoxyethylene (2) -2,2-bi (4-hydroxyphenyl) propane diacrylate, polyoxyethylene (4) -2,
2-bis (4-hydroxyphenyl) propane diacrylate] and those obtained by replacing the acrylate of the above compound with methacrylate; polyester-type diacrylate compounds [for example, trade name MANDA (Nippon Kayaku)]. Examples of the polyfunctional crosslinking agent include pentaerythritol triacrylate, trimethylethane triacrylate, trimethylolpropane triacrylate, tetramethylolmethanetetraacrylate, oligoester acrylate, and those obtained by replacing the acrylate of the above compound with methacrylate; Allyl cyanurate, triallyl trimellitate; and the like.

These cross-linking agents are used in combination with other monomer components 10
0.01 to 5 parts (further 0.03 to 3 parts)
Part).

Among these crosslinking agents, the toner resin
As an aromatic divinyl compound (particularly divinylbenzene) and a diacrylate compound linked by a chain containing an aromatic group and an ether bond, those preferably used from the viewpoint of fixing property and offset resistance are exemplified. It is preferable that at least one of the two is used for the binder resin.

In particular, as the binder resin for the toner subjected to the pressure fixing method, low molecular weight polyethylene, low molecular weight polypropylene, ethylene-vinyl acetate copolymer, ethylene-acrylate copolymer, higher fatty acid, polyamide resin And polyester resins. They are,
It is preferable to use them alone or as a mixture.

The magnetic material contained in the one-component toner according to the present invention includes iron oxides such as magnetite, hematite, and ferrite, and iron oxides containing other metal oxides;
e, metals such as Co and Ni, or these metals and Al, Co, Cu, Pb, Mg, Ni, Sn, Zn, S
b, Be, Bi, Cd, Ca, Mn, Se, Ti, W,
Alloys with metals such as V, and mixtures thereof.

These magnetic materials have an average particle size of 0.1 to 2
μm, and the magnetic properties when a 10K Oersted is applied are as follows: coercive force: 20 to 150 Oersted, saturation magnetization: 50 to 200 emu / g (preferably 50 to 10 emu / g).
0 emu / g) and those having a residual magnetization of 2 to 20 emu / g.

The one-component developer of the present invention is preferably used by adding a positive or negative charge control agent internally or externally to the developer.

As the positive charge control agent used to obtain a positively chargeable developer, known ones can be used. For example, nigrosine and its modified products such as fatty acid metal salts, quaternary ammonium salts, diorganotin oxide, diorganotin borate, and the like can be used alone or in combination of two or more. Of these, nigrosine compounds and quaternary ammonium salts are particularly preferably used.

Further,

[0067]

Embedded image

[Wherein R ₁ represents H or CH ₃ ;
₂ and R ₃ represent an alkyl group which may be substituted. Use of a homopolymer of a nitrogen-containing monomer represented by the following formula or a copolymer of a polymer monomer such as styrene, acrylate or methacrylate and the nitrogen-containing monomer as a positive charge control agent. Can be. In this case, it also has an action as (all or part of) the binder resin.

On the other hand, as the negative charge controlling agent used to obtain a negatively chargeable developer, known ones can be used. For example, carboxylic acid derivatives and their metal salts, alkoxylates, organometallic complexes, chelate compounds or the like alone or
It can be used in combination of more than one kind. Among these, acetylacetone metal complexes, salicylic acid metal complexes,
Alkyl salicylic acid metal complexes, dialkyl salicylic acid metal complexes, naphthoic acid metal complexes, and monoazo metal complexes are particularly preferably used.

When the toner used in the present invention is a one-component non-magnetic toner, any suitable pigment or dye is used as a coloring agent. Toner colorants are well known and include, for example, carbon black, aniline black, acetylene black, naphthol yellow, hansa yellow, rhodamine lake, alizarin lake, as pigments.
There are bengara, phthalocyanine blue, indaslen blue and the like. These are used in an amount necessary and sufficient to maintain the optical density of the fixed image, and are used in an amount of 0.1 to 100 parts by weight of the resin.
The addition amount is 1 to 20 parts by weight, preferably 2 to 10 parts by weight. A dye is further used for the same purpose. For example, there are azo dyes, anthraquinone dyes, xanthene dyes, methine dyes and the like.
The addition amount of 1 to 20 parts by weight, preferably 0.3 to 3 parts by weight is good.

The developer of the present invention may contain other additives as necessary. Examples of such additives include lubricants such as Teflon, polyvinylidene fluoride, and fatty acid metal salts; abrasives such as cerium chloride and silicon carbide; colloidal silica, alumina, and surface treatment agents (eg, silicone oil, various modified silicones). Oil, silane coupling agent, silane coupling agent with functional group)
Surface treated silica, surface treated alumina such as surface treated alumina, caking inhibitor; carbon black.

In order to improve the releasability of the developer of the present invention during hot roll fixing, any of the following fixing aids is added internally to the binder resin, internally added to the toner, or externally added to the toner. Can also be mixed. There are wax-like substances such as low-molecular-weight polyethylene, low-molecular-weight polypropylene, microcrystalline wax, carnauba wax, and sasol wax.
It is preferable to add 5% by weight.

The inorganic fine powder as a component of the one-component developer of the present invention includes a fine powder of an inorganic oxide and a fine powder of a carbonate compound. As inorganic oxides, magnesium,
Oxides such as zinc, aluminum, cobalt, iron, zirconium, manganese, chromium, cerium, strontium, tin and calcium titanate, magnesium titanate,
There are complex metal oxides such as strontium titanate, barium titanate, calcium zirconate, barium zirconate, barium stannate and calcium stannate. Examples of the carbonate compound include calcium carbonate, magnesium carbonate, barium carbonate and the like. Among them, strontium titanate exhibits an excellent effect.

In producing the toner according to the present invention, the above-mentioned toner constituent materials are sufficiently mixed by a ball mill or other mixer, and then sufficiently mixed by using a hot kneader such as a hot roll kneader or an extruder. After cooling and solidifying the kneaded material, a method of mechanically pulverizing and classifying the pulverized material to obtain a toner is preferable. Alternatively, a method of obtaining a toner by dispersing the constituent materials in a solution of the binder resin and then spray-drying, mixing a predetermined material with a monomer to constitute the binder resin and forming an emulsified suspension Then, there is a method for producing a toner by a polymerization method in which the toner is polymerized to obtain a toner. The toner according to the present invention may be a microcapsule toner composed of a core material and a shell material.

The developing sleeve preferably used when developing with the developer of the present invention preferably has a surface having irregularities formed by a plurality of spherical trace depressions. As a method for obtaining the surface state, a blasting method using fixed particles can be used. As the fixed particles, for example, various hard spheres made of a metal such as stainless steel, aluminum, steel, nickel, and brass having a specific particle size or various hard spheres such as ceramic, plastic, and glass beads can be used.

The developing sleeve according to the present invention can also be obtained by further performing blasting with regular particles on the surface on which random irregularities have been formed by blasting with irregular particles. Arbitrary abrasive grains can be used as the irregular shaped particles.

By subjecting the surface of the developing sleeve to blasting treatment using regular particles having specific particles, a plurality of spherical trace depressions having substantially the same diameter can be formed.

In the present invention, an apparatus in which the developing step is carried out with a one-component magnetic developer is specifically shown in FIG. 2 and will be described in detail, but this does not limit the present invention in any way.

In FIG. 2, reference numeral 1 denotes a latent image carrier (a so-called photosensitive member) such as a rotary drum type in a transfer type electrophotographic method, and a rotary drum type or the like insulator in a transfer type electrostatic recording method. A latent image carrier such as a photosensitive paper in an electrofax method, an electrostatic recording paper in a direct electrostatic recording method, and a latent image forming process device or a process mechanism not shown in the drawing on the surface thereof. An electrostatic latent image is formed and moves in the direction of the arrow.

Reference numeral 2 denotes an overall reference number of a developing device, 21 denotes a hopper containing a developer, 22 denotes a rotating cylindrical body (hereinafter referred to as a “sleeve”) as a developer carrying member (developer layer supporting member), and has a magnetic inside. A magnet generating means 23 such as a roller is incorporated.

The sleeve 22 has a substantially right half circumferential surface exposed in the hopper 21 and a substantially left half circumferential surface exposed outside the hopper, and is supported by bearings. The sleeve 22 is driven to rotate in the direction of the arrow. Reference numeral 24 denotes a doctor blade serving as a developer application member disposed with the lower side edge portion approaching the upper surface of the sleeve 22, and 27 denotes a stirring member for the developer in the hopper.

The axis of the sleeve 22 is substantially parallel to the generatrix of the latent image carrier 1, and the sleeve 22 is closely opposed to the surface of the latent image carrier 1 with a small gap α.

The surface moving speeds (peripheral speeds) of the latent image carrier 1 and the sleeve 22 are substantially the same, or the peripheral speed of the sleeve 22 is slightly higher. Between Matasen image bearing member 1 and the sleeve 22 and the alternating bias voltage applying means S ₀ or a DC bias voltage applying means S ₁
By al DC voltage and an AC voltage is superimposed is applied, straight
A flow and an alternating electric field are formed .

The substantially right half peripheral surface of the sleeve 22 is always in contact with the developer reservoir in the hopper 21, and the developer near the sleeve surface magnetically adheres to the sleeve surface by the magnetic force of the in-sleeve magnetism generating means 23. Adhered and retained as a layer and by electrostatic forces. When the sleeve 22 is rotated, adhering developer layer on the sleeve surface is advice service as a thin layer the developer layer T ₁ of the respective portions substantially uniform thickness in the process of passing through the doctor blade 24 position. The developer is charged mainly by frictional contact between the sleeve surface accompanying the rotation of the sleeve 22 and the developer in the developer reservoir near the sleeve 22. The toner thin layer surface of the sleeve 22 carries the latent image with the rotation of the sleeve. It rotates toward the surface of the body 1 and passes through the developing area A, which is the closest part between the latent image carrier 1 and the sleeve 22. During this passage, the sleeve 22
The DC and AC voltage of the developer in the thin layer
Is applied between the latent image carrier 1 and the sleeve 22 and flies between the latent image carrier 1 in the development area A and the sleeve 22 by the DC and AC electric fields formed between the latent image carrier 1 and the sleeve 22. Exercise. The toner in the final main sleeve 22 of the developer in the selectively migrate attached in accordance with the latent image potential pattern on the latent image bearing member 1 surface, the toner image T ₂ are sequentially formed You.

The sleeve surface, on which the developer has been selectively consumed after passing through the developing area A, is re-supplied by re-rotating into the developer reservoir of the hopper 21, and is supplied to the developing area A. The surface of the thin toner layer T ₁ of the sleeve 22 always rotates,
The copying process is repeatedly performed.

[0086]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, which do not limit the present invention in any way. All parts in the following formulations are parts by weight.

Example 1 100 parts of a styrene / butyl acrylate / butyl maleate / divinylbenzene copolymer (copolymerization ratio: 71.5 / 21/7 / 0.5) iron trioxide (average particle size: 85 parts ・ Chromium complex of 3,5-ditert-butylic acid 2 parts (number average diameter: 2.8 μm) ・ Low molecular weight polypropylene 3 parts

After thoroughly mixing the above materials in a blender,
The mixture was kneaded with a twin-screw kneading extruder set at 130 ° C. After cooling the obtained kneaded material and coarsely pulverizing it with a cutter mill, it is finely pulverized using a jet air flow type fine pulverizer, and the obtained finely pulverized powder is classified with a fixed wall type air classifier to obtain a classified product. Was. Further, the obtained classified product is subjected to 4 μm by a multi-segment classifier (Nippon Steel Mining Co., Ltd., elbow jet classifier) utilizing the Coanda effect.
m and below were simultaneously classified and removed to obtain a negatively chargeable magnetic toner having a weight average diameter of 9.03 μm and a weight average diameter / length average diameter of 1.34.

As shown in Table 1, the obtained magnetic toner had a weight average diameter D4 of 3.48 μm and a length average diameter D1.
Is mixed with 2 wt% of strontium titanate having a ratio of 1.98 μm and D4 / D1 = 1.76 and 0.6 wt% of hydrophobic dry silica (BET specific surface area, 250 m ^{2 /} g) by a mixer. A component developer was prepared. The strontium titanate added was the same as in the production of the toner,
Elbow jet classifier utilizing Coanda effect,
It was obtained by classification.

Next, the following developing sleeves were prepared.
That is, a glass particle of # 300 (53-62 μm), which is a spherical particle, is used for the surface of a cylindrical stainless steel (SUS 304) sleeve having a diameter of 32 mm and having a magnet inside, and a blowing nozzle diameter of 7 mm. The blast treatment was performed under the conditions of a distance between the nozzle and the sleeve of 150 mm, a blowing air pressure of 3.5 kg / cm ² , and a blowing time of 60 seconds.

As shown in FIG. 1, the prepared negatively-chargeable one-component developer is cleaned to recover the toner on the latent image carrier after transfer, and the toner is conveyed to the inside by a screw. Is supplied to the toner hopper 11 for replenishment by passing through a pipe 18 provided with the toner. Further, after the toner is gently stirred with the toner for replenishment in the hopper, the replenishment toner is supplied to the developing device 2 and modified so as to be used in the developing process. And into a Canon copier NP6060 to which the above-described developing sleeve was applied. Further, using a manuscript having a printing ratio of 6%, an image output test of 300,000 continuous sheets was performed.

As a result, as shown in Table 2, under normal temperature and normal humidity (23 ° C., 60 RH%), an image having an initial image density of 1.42 and a background fog of 1.2% was excellent in image quality. was gotten. After 300,000 prints, the developing sleeve began to reduce the unevenness of the blasting process due to the durability, but an image having an image density of 1.43 and a background fog of 0.8% and having almost the same image quality as the initial one was obtained. Was.

Similar good results were obtained under normal temperature and low humidity (23 ° C., 5 RH%) and high temperature and high humidity (30 ° C., 85 RH%).

The evaluation of the background fog was performed using a REFLECOMETER MODEL TC-6 manufactured by Tokyo Denshoku Co., Ltd.
Using 0DS, in REFLECTANCE mode, g
It measured using the reen filter and calculated by the following formula. The smaller the value, the less background fog.

Background fog (reflectance) (%) = Reflectance of standard paper (%) − Reflectivity of background portion of sample (%)

Comparative Example 1 A copy test was performed in the same manner as in Example 1 except that the inorganic fine powder having the opposite polarity to the one-component toner was not added. Table 2 shows the results. In addition,
The weight average diameter of the toner was 8.92 μm.

At room temperature and normal humidity, an image having almost the same quality as that of Example 1 was obtained at the beginning. At the time of 300,000-sheet running, in which the surface of the developing sleeve had slightly smooth irregularities, the background fog was slightly reduced to 1.8%. The image densities were almost the same.

Under low temperature and normal temperature, the initial image characteristics were almost the same as those in Example 1. However, when continuous copying was performed, fine powder of the magnetic toner began to adhere to the surface of the developing sleeve during the running. After the endurance of 10,000 sheets, uneven coating of the developer occurred on the developing sleeve. Regarding the image characteristics, the image density was reduced due to the sleeve coating unevenness, and the background fog was 2.6%, which was inferior to Example 1.

Example 2 A developer was prepared in the same manner as in Example 1 except that the production conditions (crushing and classification) of the one-component toner were changed and a one-component toner having a weight average diameter of 10.82 μm was used. An evaluation was performed. Table 2 shows the results. Under normal temperature and normal humidity and normal temperature and low humidity, an image similar to that of Example 1 was initially obtained. However, when 300,000 sheets were used, the image density in both environments was 1.33, which was slightly lower than the initial value. Dropped. But,
It was not at a level that would cause quality problems. Other image characteristics were almost the same as in Example 1.

Example 3 A developer was prepared in the same manner as in Example 1 except that the production conditions (crushing and classification) of the one-component toner were changed and a one-component toner having a weight average diameter of 5.28 μm was used. An evaluation was performed. Table 2 shows the results. Under all circumstances, the degree of fogging was slightly poor from the beginning, and an image having poor cleaning properties was sometimes obtained after 300,000 sheets. However, it was not at a level that would pose a practical problem. Other image characteristics were almost the same as in Example 1.

Comparative Example 2 A developer was prepared in the same manner as in Example 1 except that the production conditions (crushing and classification) of the one-component toner were changed and a one-component toner having a weight average diameter of 13.20 μm was used. An evaluation was performed. Table 2 shows the results. 3 in all environments
The image density after 100,000 sheets was poor, and was not practically endurable.

Comparative Example 3 A developer was prepared in the same manner as in Example 1, except that the manufacturing conditions (crushing and classification) of the one-component toner were changed and a one-component toner having a weight average diameter of 3.89 μm was used. An evaluation was performed. Table 2 shows the results. Under all circumstances, the degree of background fogging was poor from the beginning, and the cleaning property was inferior to that of Example 1.

Example 4 As shown in Table 1, strontium titanate added to the toner has a weight average diameter D4 of 4.53 μm, a length average diameter D1 of 2.38 μm, and D4 / D1 of 1.90. A developer was prepared and evaluated in the same manner as in Example 1, except for using. Table 2 shows the results. In all environments, the image density after 300,000 sheets was slightly inferior to that of Example 1, but was not at a practically problematic level. Other image characteristics were almost the same as in Example 1.

Example 5 As shown in Table 1, strontium titanate added to the toner had a weight average diameter D4 of 1.08 μm, a length average diameter D1 of 0.71 μm, and D4 / D1 of 1.52. A developer was prepared and evaluated in the same manner as in Example 1, except for using. Table 2 shows the results. Under all circumstances, the image density at the initial stage and after 300,000 sheets was slightly inferior to that of Example 1, but not at a level that would pose a problem in practical use. Further, under normal temperature and low humidity, the toner layer on the sleeve after 300,000 sheets was uneven, but it was not enough to affect image characteristics. Other image characteristics were almost the same as in Example 1.

Comparative Example 4 As shown in Table 1, strontium titanate added to the toner had a weight average diameter D4 of 6.13 μm, a length average diameter D1 of 3.02 μm, and a ratio of D4 / D1 of 2.03. A developer was prepared and evaluated in the same manner as in Example 1, except for using. Table 2 shows the results. In all environments, the image density after 300,000 sheets is 1.1 at room temperature and normal humidity.
5. Under normal temperature and low humidity, 1.13 was inferior to Example 1 and was not practically endurable.

Comparative Example 5 As shown in Table 1, strontium titanate added to a toner had a weight average diameter D4 of 0.58 μm, a length average diameter D1 of 0.52 μm, and D4 / D1 of 1.12. A developer was prepared and evaluated in the same manner as in Example 1, except for using. Table 2 shows the results. Under all circumstances, the image density was low from the beginning. Further, under normal temperature and low humidity, the toner layer on the sleeve after 300,000 sheets became uneven, resulting in a decrease in image density and was not usable.

Example 6 As shown in Table 1, strontium titanate added to the toner had a weight average diameter D4 of 3.53 μm, a length average diameter D1 of 1.54 μm, and D4 / D1 of 2.29. A developer was prepared and evaluated in the same manner as in Example 1, except for using. Table 2 shows the results. In all the environments, the image density and the cleaning property after 300,000 sheets were slightly inferior to those in Example 1, but were not at a practically problematic level. Other image characteristics were almost the same as in Example 1.

Comparative Example 6 As shown in Table 1, strontium titanate added to the toner had a weight average diameter D4 of 4.08 μm, a length average diameter D1 of 1.58 μm, and D4 / D1 of 2.58. A developer was prepared and evaluated in the same manner as in Example 1, except for using. Table 2 shows the results. The image density after 300,000 sheets is 1.15 under normal temperature and normal humidity, and 1.15 under normal temperature and low humidity.
14 was inferior to Example 1 and was not practically endurable.

Example 7 As shown in Table 1, a developer was prepared and evaluated in the same manner as in Example 1 except that the amount of strontium titanate added to the toner was 5.5 wt%. went. Table 2 shows the results. At the initial stage, the same image characteristics as in Example 1 were obtained under all circumstances. However, after 300,000 sheets, the image density and the cleaning property were inferior to those in Example 1. However, it was not at a level that would pose a practical problem.

Example 8 As shown in Table 1, a developer was prepared and evaluated in the same manner as in Example 1 except that the amount of strontium titanate added to the toner was 0.5 wt%. went. Table 2 shows the results. In all the environments, the image density was slightly lower than in Example 1 from the beginning. In addition, under normal temperature and low humidity, the toner layer on the sleeve was uneven from the beginning, but it was not enough to affect image characteristics. For other image characteristics, see Example 1.
Was almost equivalent to

Comparative Example 7 As shown in Table 1, a developer was prepared in the same manner as in Example 1 except that the amount of strontium titanate added to the toner was 8.0 wt%, and the evaluation was performed. went. Table 2 shows the results. At the initial stage, the same image characteristics as in Example 1 were obtained under all circumstances. However, cleaning failure occurred in the image after 300,000 sheets, and the image density was poor, so that the image could not be used.

Comparative Example 8 As shown in Table 1, except that the amount of strontium titanate added to the toner was 0.07 wt%.
A developer was prepared and evaluated in the same manner as in Example 1.
Table 2 shows the results. Under all circumstances, the image density was slightly lower than in Example 1 from the beginning.
In addition, under normal temperature and low humidity, the toner layer on the sleeve after 300,000 sheets had severe uneven ripples, resulting in a decrease in image density, which was not at a usable level.

Comparative Example 9 A developer was prepared in the same manner as in Example 1 except that a one-component toner having a weight average diameter of 9.38 μm and a weight average diameter / length average diameter of 2.09 was used. , Was evaluated. Table 2 shows the results. Under all circumstances, the image characteristics after 300,000 sheets were slightly inferior to Example 1.

[0114]

[Table 1]

[0115]

[Table 2]

[0116]

According to the present invention, the one-component toner as shown in the present invention includes:
A collected product obtained by developing and transferring a one-component developer obtained by adding an inorganic fine powder having a specific particle size distribution to a latent image on a latent image carrier, and cleaning the latent image carrier after the transfer. Is supplied to a developing unit and used in a developing process, whereby a high-quality image can be always provided with a high image density under various environments for a long period of time.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view of a developing device used for image output in Examples and Comparative Examples.

FIG. 2 is a specific sectional view of a developing device used in a developing process.

FIG. 3 is a simplified diagram of a charge amount measuring device.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 latent image carrier 2 developing device 11 developer supply hopper 13 pre-transfer charger 14 transfer charger 15 separation charger 16 cleaner 17 primary charger 18 transfer pipe with transfer screw remaining developer 21 hopper 22 Developer carrier (sleeve) 23 Magnetic roller 24 Doctor blade 27 Developer stirring member in hopper T Developer in hopper T ₁ Developer on sleeve T ₂ Developer on latent image carrier S ₀ Alternating bias voltage applying means S ₁ DC bias voltage applying means A Developing area α Gap between latent image carrier and sleeve 31 Aspirator 32 Measuring vessel 33 Screen 34 Lid 35 Vacuum gauge 36 Air flow control valve 37 Suction port 38 Condenser 39 Electrometer

Continuation of the front page (56) References JP-A-3-294864 (JP, A) JP-A-4-214568 (JP, A) JP-A-4-140758 (JP, A) JP-A-5-297631 (JP) JP-A-5-197200 (JP, A) JP-A-1-237561 (JP, A) JP-A-5-165257 (JP, A) JP-A-1-214874 (JP, A) JP 64-80981 (JP, A) JP-A-3-126043 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G03G 9/08

Claims (6)

(57) [Claims] 1. An image forming apparatus, comprising: a surface facing a latent image carrier;
The surface of the developer carrier that has been
An image agent layer is formed, and the latent image carrier and the developer carrier are
DC and AC electric fields are formed in the vicinity of the development area
By doing so, the one-component developer is applied to the surface of the developer carrier.
By et fly, toner develops the latent image on said image bearing member
A system for forming an image, transferring the toner image on the latent image carrier to a transfer material, and cleaning the surface of the latent image carrier after transfer to supply a collected product obtained to a developing device to a developing device for use in a developing process in one-component developing agent used in, the one-component developer is contained and monocomponent toner and inorganic fine powder you containing at least a binder resin and a colorant, the one-component toner has a weight-average diameter D4 is 4 to 11 μm
The ratio of the weight average diameter D4 to the length average diameter D1 (D4 / D
1) is 1.01-2, the inorganic fine powder has a weight average diameter D4 of 0.6-5 μm, a length average diameter D1 of 0.5-4 μm, and a weight average
The ratio ( D4 / D1 ) of the diameter D4 to the average length diameter D1 is 2.4.
A one-component developer, wherein the inorganic fine powder is added in an amount of 0.3 to 5% by weight based on the one-component toner. 2. The one-component toner according to claim 1, wherein the colorant is magnetic.
Claims: It is a magnetic toner containing a body.
2. The one-component developer according to 1. 3. The one-component toner according to claim 1, wherein the colorant is a pigment.
Or a non-magnetic toner containing a dye.
The one-component developer according to claim 1, wherein 4. A disposition opposed to the surface of the latent image carrier with a gap.
The surface of the developer carrier that has been
An image agent layer is formed, and the latent image carrier and the developer carrier are
DC and AC electric fields are formed in the vicinity of the development area
By doing so, the one-component developer is applied to the surface of the developer carrier.
By et fly, toner develops the latent image on said image bearing member
Forming an image, transferring the toner image on the latent image carrier to a transfer material, cleaning the surface of the latent image carrier after transfer, supplying the collected product obtained to the developing device to an image used in the developing process in forming methods, the one-component developer is contained and monocomponent toner and inorganic fine powder you containing at least a binder resin and a colorant, the one-component toner has a weight average particle diameter D4 is 4~11μm In
The ratio of the weight average diameter D4 to the length average diameter D1 (D4 / D
1) is 1.01-2, and the inorganic fine powder has a weight average diameter D4 of 0.6-5 μm, a length average diameter D1 of 0.5-4 μm, and a weight average
The ratio ( D4 / D1 ) of the diameter D4 to the average length diameter D1 is 2.4.
Hereinafter, and the image forming method of the addition amount of the inorganic fine powder is characterized in the 0.3 to 5 wt% der Turkey with respect to the one-component toner. 5. The one-component toner according to claim 1, wherein the colorant is magnetic.
Claims: It is a magnetic toner containing a body.
5. The image forming method according to item 4. 6. The one-component toner according to claim 1, wherein the colorant is a pigment.
Or a non-magnetic toner containing a dye.
The image forming method according to claim 4.