JPS6087346A - Developing method - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for developing an electrostatic latent image formed on a surface of a latent image carrier, particularly a method for developing a thin and uniform layer of insulating toner on a toner carrier. It is related to.

Conventionally, the following methods are known as developing methods using -component nonmagnetic or weakly magnetic toners.

For example, in an electrostatic image development method in which a developer carrier holding a developer on its surface is opposed to a latent image carrier to develop an electrostatic image on the surface of the carrier, the developer is stored in a developer storage means. When pumping up the developer under the developer carrier onto the developer carrier, vibration is applied to the developer in the pumped-up portion to activate it and form a developer layer of a predetermined thickness on the surface of the developer carrier. There is a developing method in which the component-based non-magnetic toner particles are formed and subjected to development; It has a developing roller for transferring the electrostatic image and developing the electrostatic image on the electrostatic image holder, and maintains a gap between the electrostatic image holder and the developing roller in the developing section, and the length of the gap is determined by the length of the developing roller. There is a method of developing an electrostatic image by setting the thickness to be larger than the thickness of the above toner coating layer.

The movable developer carrying means carries and conveys the developer and supplies it to the latent image holding member, the developer replenishing means, and the movable developer carrying means receives the developer from the developer replenishing means and develops the image on the movable developer carrying means. A movable applicator for applying a developer, which has a fiber brush that carries a developer on its surface, contacts the movable developer carrier, and moves in the same direction as the movable developer carrier at this abutting portion. There is a method in which toner is uniformly applied to the surface of the movable developer carrying means using a movable coating means that moves at a higher speed than the movable developer carrying means, and the toner is brought close to the electrostatic latent image area to perform development. be.

Compared to conventional developing methods using one-component toner, these methods apply strong pressure when applying the toner to the toner carrier, which increases the triboelectric charge level of the toner, and the friction increases with development time. This method has the disadvantage that the image density of the resulting copy changes over time as the band and charge range increases, and the quality of the copy cannot be kept constant.

In addition, these methods are methods in which insulating non-magnetic or weakly magnetic toner is supported on a carrier mainly by non-magnetic force in a developing section and developed. The forces that cause the toner to be supported on the carrier are mainly electrostatic attraction and physical adhesion, and in this respect, conventional insulating magnetic toner is used in which the toner is supported on the carrier by magnetic force, electrostatic force, etc. Various disadvantages arise compared to developing methods. For example, a phenomenon occurs that many toners are not applied relatively thinly and uniformly on the carrier.

Furthermore, for example, even if the toner is applied relatively uniformly, toner adheres to non-image areas, which is called smearing. Furthermore, even if the toner is applied thinly and uniformly, the amount of toner adhering to the image area is insufficient, resulting in an image with low density. Additionally, many toners can produce very poor images with low fidelity and low resolution even when applied evenly. Furthermore, repeated use of more toner results in decreased image density and lower quality images. Furthermore, many toners have the disadvantage that they sometimes cause a decrease in image density when exposed to environmental changes such as high temperature and high humidity, low temperature and low humidity, and sometimes cause blurring.

In addition, in the developing method using -component magnetic toner, since the magnetic toner particles contain a large amount of magnetic powder, they are not only more expensive than toners that are non-magnetic or weakly magnetic, but also beautiful. Colorization was an afterthought.

An object of the present invention is to provide a new developing method using an insulating non-magnetic or weakly magnetic toner that overcomes the above-mentioned drawbacks. That is, an object of the present invention is to provide a developing method with high fidelity and stable image quality. Furthermore, it is an object of the present invention to provide a developing method that eliminates the drying effect and provides a high-resolution image that is uniform and has sufficient density in the image area.

Another object of the present invention is to provide a developing method using an insulating non-magnetic toner that has excellent durability such as continuous use characteristics.

Another object of the present invention is to provide a developing method using an insulating nonmagnetic toner that is stable against environmental changes such as high temperature and high humidity, and low temperature and low humidity.

Another object of the present invention is to provide a developing method that provides images with sharp hues.

The developing method of the present invention is characterized in that an electrostatic image carrier that holds an electrostatic image on its surface and a toner carrier that carries toner on its surface are arranged with a certain gap in the developing section, and A toner having a true specific gravity of 1.2 or less and a degree of aggregation of 30% or less at a relative humidity of 60% is supported on a toner carrier to a thickness thinner than the gap, and the toner is transferred to the electrostatic image carrier during development fAs. There is a development method in which the film is transferred to and developed.

In the developing method of the present invention, if necessary, an alternating current and/or
Alternatively, it is preferable to apply a DC bias.

The present inventors investigated various developing methods using conventionally known non-magnetic or weakly magnetic toners, and found that in order to solve the above-mentioned drawbacks, it was necessary to compare the developing methods using magnetic toners. It was discovered that iX2 allows for more precise control of the amount of electrostatic charge and fluidity of the toner on the toner carrier in the developing section. For example, if the amount of charge is low, the toner will not be applied uniformly on the toner carrier, and uniform development will not be possible, and even if the amount of charge is increased and evenly applied conditions are created, the value will not be appropriate. If the value is too high, the electrostatic attraction between the toner carrier and the toner carrier will be too strong, making it difficult for the toner to transfer to the electrostatic image carrier. This results in a decrease in density and the appearance of a low-quality image. Therefore, in order to uniformly apply a non-magnetic toner or a weakly magnetic toner containing a magnetic substance with a specific gravity of only about 1 or 2 onto a toner carrier in a state where sufficient development is possible, it is necessary to precisely control the fluidity of the toner. Therefore, it was concluded that it is necessary to appropriately adjust the degree of cohesion of the toner to 1.1.

The present invention solves the above problems caused by a method in which a toner having so-called weak magnetism, which is non-magnetic or contains only a magnetic substance with a true north m 1.2 or less, is carried on a carrier mainly by non-magnetic force in a developing section and developed. These requirements are achieved by adjusting the degree of cohesion of the toner.

The non-magnetic or weakly magnetic toner having a degree of aggregation as in the present invention was uniformly coated on the carrier and showed good development even by various coating methods as described below. Furthermore, this remained unchanged even under high temperature and high humidity environments, low temperature and low humidity environments, and after long-term image production.

The method for measuring the degree of aggregation used in the present invention is to place toner on a sieve, apply vibrations, and measure the proportion of toner remaining on the sieve.

According to this method, the greater the proportion of toner remaining on the sieve, the greater the degree of toner aggregation, indicating that toner particles tend to aggregate and behave. Specifically, it is thin and the temperature is 25 ± 1 using a powder tester manufactured by Micrometix Laboratory.
Measured under conditions of ℃ and humidity of 60±5%.

Line up sieves of 60 mesh, 100 mesh, and 200 mesh in this order from above and set them on a shaking table. 2 g of toner was set on a 60-mesh sieve, and a voltage of 47 V was applied to the vibration system to give vibration for 40 seconds.

After completion, the weight of the toner remaining on each sieve is measured, weighted with 0.5, 0.3, and 0.1, respectively, and added to express the degree of aggregation as a percentage.

As the binding N resin of the toner, monopolymers of styrene and its substituted products such as polystyrene, polyP-chlorostyrene, and polyvinyltoluene; styrene-P-chlorostyrene co-111f polymers, styrene-propylene copolymers, and styrene-vinyl Toluene copolymer, styrene-vinylnaphthalene copolymer, styrene-methyl acrylate copolymer, styrene-acrylic ethyl copolymer, styrene-
Butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-
Butyl methacrylate copolymer, styrene-alpha chloromethyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-vinyl methyl ether copolymer,
Styrene-vinylethyl ether copolymer, styrene-
Styrene such as vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile-indene copolymer, styrene-maleic [; System copolymers; polymethyl methacrylate, polybutyl methacrylate, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, polyester, polyurethane, polyamide, epoxy resin, polyvinyl butyral, polyacrylic acid resin, rosin, modified rosin, terpene resin, Phenol resin, aliphatic or alicyclic hydrocarbon resin, aromatic petroleum resin, chlorinated paraffin, paraffin wax, etc. can be used alone or in combination.

As the coloring material used in the toner, conventionally known carbon black, dye, pigment, etc. can be used, and conventionally known positive or negative charge control agents can be used in the present invention.

In order to use the toner as a magnetic toner, it may contain magnetic powder. The magnetic powder used is a substance that is magnetized when placed in a magnetic field, and includes powders of ferromagnetic metals such as iron, cobalt, and nickel, and alloys and compounds such as magnetite, hematite, and ferrite.

The content of this magnetic powder is preferably 15% by weight or less based on the weight of the toner.

The toner is optionally mixed with carrier particles such as iron powder, glass beads, nickel powder, ferrite powder, etc.
Used as a developer for electrical latent images.

Furthermore, the toner used in the present invention may be produced by any method. For example, there are those that undergo kneading, pulverization, and classification as conventionally known, and those that are dispersed in a liquid phase or gas phase and granulated. Alternatively, it may be microencapsulated.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below based on embodiment examples and with reference to the drawings.

FIG. 1 shows an example of an embodiment of an electrostatic latent image developing method and a developing device using an insulating toner. In the figure, reference numeral 1 denotes a cylindrical electrostatic image carrier, which is electrostatically imaged by, for example, the Carlson method or the NP method, which are known electrophotographic methods. A latent image is formed, and the insulating toner 5 in a hopper 3, which is a toner supply means, is developed with the toner 5 applied by a coating means 4, which coats the toner carrier 2 by controlling the thickness of each toner layer. .

The toner carrier 2 is a cylindrical developing roller made of stainless steel. Aluminum may be used as the material for this developing roller, or other metals may be used. Also metal p
- A coating coated with a resin or the like may be used to triboelectrically charge the toner to a desired polarity.

Additionally, the developer roller may be made of an electrically conductive non-metallic material. Although not shown in the drawings, spacer rollers made of high-density polyethylene are inserted into the shafts of both ends of the toner carrier 2. By applying these spacer rollers to both ends of the electrostatic image holder 1 and fixing the developing device, the distance between the electrostatic image holder 1 and the toner carrier 2 is adjusted so that the toner coated on the toner carrier 2 is Set and hold at a thickness greater than . This spacing is, for example, 100μ to 500μ, preferably 150μ to 300μ. If this distance is too large, the electrostatic force exerted by the electrostatic latent image on the electrostatic image carrier 1 on the non-magnetic toner applied on the toner carrier 2 will be weak, and the image quality will deteriorate, especially the visualization of fine lines during development. becomes difficult.

Furthermore, if this distance is too narrow, there is a great risk that the toner applied on the toner carrier 2 will be compressed and aggregated between the toner carrier 2 and the electrostatic image holder 1. 6 is a developing bias power supply, which connects the toner carrier 2 and the electrostatic image carrier 1;
This allows a voltage to be applied between the back electrode and the back electrode. This developing bias voltage is a developing bias voltage as described in Japanese Patent Publication No. 58-32375.

FIG. 2 is a diagram showing another example of the embodiment.

In the figure, 1 is an electrostatic image carrier, 2 is a toner carrier,
5 is toner, 3 is hopper, 9 is cleaning blade,
10 indicates a toner supply member.

16 is a vibration member, 17 is a vibration generating means, 16a is a permanent magnet, 16b is a support spring, 17a is an iron core, and 17b is a winding wire. By applying an alternating current to the winding 17b, the vibrating member 16 is vibrated with an appropriate amplitude and frequency to form a uniform toner coating layer on the toner carrier 2 which is rotating at a constant speed, and to form a uniform toner coating layer on the toner carrier 2 which is rotating at a constant speed. The electrostatic image holder 1 is placed in opposition with a gap larger than the thickness of the toner coating layer, and the nonmagnetic toner is flown onto the electrostatic image to develop it. The vibration of the vibrating member 16 may be at any level as long as it does not cause liquid to flow directly onto the toner carrier 2, but it is preferable to control the frequency and amplitude so that the toner coating layer has a uniform thickness of about 5 to 100 μm. . It is also possible to apply an alternating current and/or direct current developing bias voltage between the toner carrier 2 and the electrostatic image holder 1.

FIG. 3 is a diagram showing another example of the embodiment.

In the figure, 1 is an electrostatic image holder, 2 is a special toner carrier, and 3 is a toner carrier.
is a developing container, 5 is a toner, 6 is a developing bias power source, 9
35 is a toner cleaning member, 35 is an application roller, and 36 is a toner cleaning member.
4 indicates a fiber brush fixed to the surface thereof, and 40 indicates a bias power source for application. The toner 5 is uniformly coated on the toner carrier 2 by rotating the coating roller 35 and conveyed by the brush 36, and is caused to fly onto the electrostatic image on the electrostatic image holder 1 for development. The gap between the toner carrier 2 and the application roller 35 is adjusted so as to form a uniform toner layer of about 5 to 100μ on the toner carrier 2, and the application bias power supply 40 is used to apply a bias voltage in order to uniformly apply the toner. may be applied. The gap between the electrostatic image carrier 1 and the toner carrier 2 is set to be larger than the thickness of the toner, and a developing bias from the developing bias '6M6 may be applied during development.

FIG. 4 is a diagram showing another example of the embodiment.

In the figure, 1 is an electrostatic image carrier, 2 is a toner carrier,
5 is toner, 43. 48 is a developing container, 48 is a magnetic roller, 49 is its nonmagnetic sleeve, 5° is a magnet, 52 is a magnetic brush, and 53 is a one-component toner or a two-component developer in which toner and magnetic particles are mixed. By magnetically holding magnetic particles on the non-magnetic sleeve 49 to form a brush, and rotating the non-magnetic sleeve 49, the toner or developer 5
A uniform layer 5 of toner is formed by drawing up the toner 3 with the carrier brush and contacting it onto the toner carrier 2. At this time, since the carrier is held on the magnetic roller 48 by magnetic force, it does not move onto the toner carrier 2. Next, the toner is developed by flying from the toner carrier 2 onto the electrostatic image holder 1. The gap between the magnetic roller 48 and the toner carrier 2 is adjusted so that the thickness of one layer of toner on the toner carrier 2 is about 5 to 100 μm.

The gap between the toner carrier 2 and the electrostatic image holder 1 may be made larger than the thickness of the toner, and a developing bias voltage may be applied to the toner carrier 2.

FIG. 5 is a diagram showing still another example of the embodiment. In the figure, 1 is an electrostatic image carrier, 2 is a toner carrier, 3 is a hopper, 6 is a developing bias power source, 5 is toner, 50 is a fixed magnet, 52 is a magnetic particle, and a Vi magnetic brush 58 made of a toner mixture is The toner-4 regulating blade is shown. A magnetic brush 52 formed on the toner carrier 2 is circulated by rotating the toner carrier 2, takes in the toner in the hot spring 3, and uniformly coats the toner carrier 2 in a thin layer. The toner carrier 2 and the electrostatic image carrier 1 are opposed to each other with a gap greater than the thickness of the toner layer, and the non-magnetic toner 5 on the toner carrier 2 is transferred onto the electrostatic charge image on the electrostatic image carrier 1. Perform flying development. The charge amount and thickness of one layer of toner are determined by the magnetic brush 5.
This is controlled by the size of the brush and the degree of circulation of the brush.

The gap between the electrostatic image carrier 1 and the toner carrier 2 is set to be larger than the thickness of the toner.

The developing bias may be applied by the developing bias power supply 6.

FIG. 6 is a diagram showing still another example of the embodiment of the present invention. In FIG. 6, l is a cylindrical electrophotographic photoreceptor that moves in the direction of arrow a. A non-magnetic sleeve 2 serving as a toner carrier is provided with a gap between the photoreceptor 1 and the photoreceptor 1 . This sleeve 2 rotates in the direction of the arrow as the photoreceptor 1 moves. A fixed magnet 50 is provided within the sleeve 2 as a magnetic field generating means. Reference numeral 3 designates a hopper as a developer supply container, which accommodates a developer mixture having toner 5 and magnetic particles 60 together with the sleeve 2.0 Near the surface of the sleeve 2 corresponding to the magnetic pole 62 of the magnet 50, the magnetic particles A magnetic brush 60 is formed. When the sleeve 2 is rotated in the direction of the arrow, the magnetic pole 6
By appropriately selecting the arrangement position of 2 and the fluidity and magnetic properties of the magnetic particles 60, the magnetic brush circulates in the direction of arrow C near the magnetic pole 62, forming a circulation layer 66.

On the other hand, a point 68 downstream of the magnetic pole 62 in the sleeve rotation direction
At the position shown in FIG.
Law of sleeve 2 in position 8, 9i! The sleeve is arranged so as to be inclined toward the downstream side in the direction of movement of the sleeve, with an angle δ formed between n and the center line e of the blade. The magnetic particles 60 are restrained at a point 68 on the surface of the sleeve 2 by a balance between the restraining force based on the effects of gravity, magnetic force, and the presence of the magnetic blade 64, and the conveyance force in the direction of movement of the sleeve 2, and can move to some extent. forms a stationary layer 65 that is almost immobile. The magnetic particle layer consisting of the circulation layer 66 and the stationary layer 65 is the sleeve 2.
formed on the surface of The magnetic particle layer contains the toner 5, and the magnetic particles of the stationary layer 65 are restrained on the sleeve surface by the balance between the restraining force and the conveying force described above, but since the toner is substantially non-magnetic, It is not restrained by the magnetic field of the magnetic pole 62, but is evenly coated on the sleeve surface by the mirroring force, is transported as the sleeve rotates, and is exposed to the surface of the photoreceptor 1 for development.

In the circulation layer 66, the magnetic brush is circulated as shown by arrow C due to the magnetic force and frictional force due to gravity and magnetic poles, and the fluidity (viscosity) of the magnetic particles, and the magnetic brush is on the magnetic particle layer during this circulation. The toner 5 is taken in from the developer layer 67 and returned to the lower part of the gun 3, and this circulation is repeated thereafter.

The magnetic blade 64 does not directly participate in this circulation.

The developing method used here is Special Publication No. 58-3237
The method described in No. 5 is preferred. A voltage is applied between the electrophotographic photoreceptor 1 and the toner carrier 2 by an asumi source 6 . The bias power supply 6 may be alternating current or direct current, but
One in which direct current is superimposed on alternating current is preferable. The developer provided by the development is supplied to the toner carrier 2 from the circulation layer 66, and the insufficient amount in the circulation layer 66 is supplied from the developer layer 67 by the above-mentioned circulation movement.

[Example 1] The above materials were thoroughly mixed in a blender and then kneaded with two rolls heated to 150°C. The kneaded material was left to cool naturally, then coarsely pulverized using a cutter mill, pulverized using a pulverizer using a jet stream, and further classified using an air classifier to obtain a toner having an average particle size of 12 μIn. True specific gravity is 1.05.
The degree of aggregation was 21%.

On the other hand, 100 parts by weight of zinc oxide, 20 parts by weight of styrene-butadiene copolymer, 40 parts by weight of n-butyl methacrylate, 1zOtjf part of toluene, 191 parts by weight of rose bengal;
A mixture consisting of 4 parts by weight of methanol solution was dispersed and mixed in a ball mill for 6 hours. This was applied to a 0.05 mm thick aluminum plate using a wire bar so that the dry coating thickness was 40 μm, and the solvent was evaporated with warm air to produce a zinc oxide binder-based photoreceptor in the form of a drum.

This photoreceptor was subjected to a corona discharge of 16 KV to uniformly charge the entire surface, and then an original image was irradiated to form an electrostatic latent image.

When the toner was put into a developing device as shown in FIG. 1, a uniform coating was obtained, and the electrostatic latent image formed above was developed. In this case, the toner carrier 2 has an outer diameter of 5
A stainless steel cylindrical sleeve with 0 fins was used, the distance between the photosensitive drum surface and the sleeve surface was set to 0.25 mm, and the sleeve was heated at 400 Hz 1 ooov (D cross R and U -
A 15 oV) iif flow bias was applied.

Next, the powder image was transferred while irradiating a direct current corona of 17 KV from the back side of the transfer paper to obtain a copied image.

For fixing, use a commercially available plain paper copier (part name: NP-so
o, manufactured by Canon).

The resulting transferred image had a sufficiently high density of 1633, had no fogging, had no toner scattering around the image, and was a good image with high resolution. Durability was continuously examined using the above toner, and the transferred image after 10,000 sheets was also an image with no dull color compared to the initial image.

Furthermore, when the environmental conditions were set to 35°C and 85%, the density of one image was 128, a value that was almost unchanged from normal temperature and humidity.
A clear blue image was obtained without fogging or scattering, and the durability remained almost unchanged until 10,000 sheets were printed. Next 1
When a transferred image was obtained at a low temperature and low humidity of 10% at 0° C., the image density was 1.32, the solid black areas were developed and transferred extremely smoothly, and the image was excellent with no hollow spots even if it was scattered. Durability tests were conducted under these environmental conditions in continuous and intermittent modes, and the density fluctuation was ±0.2 up to 0.00 sheets, which was sufficient for practical use.

[Comparative Example 1] The toner of Example 1 was made into an average particle size of 7 μm by changing the pulverization conditions and classification conditions. The degree of aggregation was 38%. When this was coated on a holder in the same manner as in Example 1, it was only thinly coated and the image density was low, making it impossible to obtain a good image.

[Example 2] The toner of Example 1 was put into the device shown in FIG. 2, and the vibrating member 16 was vibrated at a frequency of about 5 QHz and an amplitude of 0.2 QHz.
When the toner carrier 2 is rotated at a circumferential speed of 120 mm/sOc, a uniform toner coating layer with a thickness of about 50 μm is formed on the toner carrier, and the toner carrier 2 and the electrostatic image holder l are separated by about 3 μm.
Facing each other with a gap of 00μ, the surface potential of the most hatched surface is -60μ.
For an electric latent image of 0V, a frequency of 10 is applied to the toner carrier 2.
0 to several kilohertz, minus peak value -660 to -1
When development was carried out by applying a bias AC electric field of 200 V and a plus peak value of +400 to +800 V, similar good results were obtained. On the other hand, when the toner of Comparative Example 1 was developed as described above, the defects described in Comparative Example 1 were noticeable.

[Example 3] A toner having an average particle size of 11 μm was obtained.

The degree of aggregation was 16%, and the true specific gravity was 1.08.

This toner is put into the developing device shown in FIG. 3 in which the gap between the toner holder 2 and the application roller 35 is set to about 2 mm, and the length of the fiber brush 36 is set to about 3 g. A single layer of toner of approximately 30μ was formed on the developing roller while maintaining a gap of 300μ with a frequency of 20014z, a DC component of 250V was added to the pressure peak value ±450V, and the voltage peak value +700μ and - 2
Similar good results were obtained when a photoconductor for NP-20OJ manufactured by Canon Co., Ltd. was developed using a photoreceptor for NP-20OJ manufactured by Canon.

[Comparative Example 2] A toner having an average particle size of 12 μm was obtained. Coagulation 1.4
[was 45%, true specific gravity was 1.00.

When this toner was developed in the same manner as in Example 3, a good coating state could not be obtained, resulting in a poor image.

[Example 4] The toner 202 of Example Vil+ 3 was mixed with the ferrite carrier 402, the gap between the toner carrier 2 and the magnetic roller 48 was about 2 mm, and the maximum thickness of the magnetic brush 52 was about 3 mm.
The sample is placed in the developing device shown in Fig. 4, which is set so that
0 [Example 5] The toner 20f of Example 1 was mixed with the iron powder carrier 209 in advance, and the mixture was transferred to the regulating blade 58 to carry the toner. The sample was placed in the developing device shown in FIG. 5, which was set so that the gap with the body 2 was approximately 250 μm, and development was performed in the same manner as in Example 1, and the same good results were obtained.

[Example 6] Developing device shown in FIG. 6 in which 20 t of toner of Example I111 was mixed with ferrite carrier 50F in advance, and the gap between regulating cartridge v-drawer 4 and toner carrier 2 was set to be about 300 μ. When developed in the same manner as in Example I, the same good results were obtained.

[Brief explanation of drawings]

FIG. 1 and FIG. 6 are cross-sectional views showing different types of developing devices used for carrying out the developing method according to the present invention. l... Static image holder, 2... Toner carrier, 3...
Hopper, 4... Toner application means, 5... -component non-magnetic toner, 6... Effect 1 bias power supply, 9...
toner cleaning blade, lO...toner supply member, 16...vibration member, 17...vibration generating means, 3
5... Application roller, 36... Fiber brush, 40...
・Coating bias power supply, 48...Magnetic roller, 49・
...Nonmagnetic sleeve, 50...Permanent magnet, 52...
Magnetic brush, 53...-component non-magnetic toner or a two-component developer mixed with it and magnetic particles, 58... Regulating blade. Applicant Canon Co., Ltd. No./Figure 2! Missing J

Claims (1)

[Claims] An electrostatic image carrier that holds an electrostatic image on its surface and a toner carrier that carries toner on its surface are arranged with a certain gap in the developing section, and the degree of aggregation at 25° C. and relative humidity of 60% is 30. % or less, with a true specific gravity of 1.2 or less, is supported on a toner support member to a thickness thinner than the gap, and the toner is transferred to the ap electrostatic image holder in a developing section for development. development method.