JP2714252B2 - Electrostatic latent image developing developer, image forming apparatus and apparatus unit - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for forming a latent image on an image carrier such as an electrophotographic photosensitive member or an electrostatic recording dielectric, and developing the latent image to visualize the latent image. The present invention relates to a developer for developing an electrostatic latent image applied to an apparatus, an image forming apparatus, an apparatus unit, and a facsimile apparatus.

(Background technology)

Conventionally, for example, a developing device that visualizes a latent image formed on the surface of a photosensitive drum as an electrostatic latent image carrier with a magnetic toner as a one-component developer has been developed by friction between magnetic toner particles and developer. A charge of a polarity opposite to the electrostatic image charge formed on the photosensitive drum and the development reference potential is applied to the magnetic toner particles by friction between the sleeve as a carrier and the magnetic toner particles, and the magnetic toner is extremely thinly applied on the sleeve. It is applied and transported to the developing area formed by the photosensitive drum and the sleeve. In the developing area, the magnetic toner flies under the action of the magnetic field from the magnet fixed inside the sleeve to visualize the electrostatic latent image on the photosensitive drum. What is known is.

However, in the above-described conventional example, there is a problem that a low density portion is generated vertically when the same image pattern is repeatedly printed. FIG. 2 shows a schematic diagram of the image. In a character image, the character is thinned, and in a halftone or solid black image, the density is low. This phenomenon is hereinafter referred to as fading.

Further, the fading phenomenon is particularly remarkable in a high-temperature and high-humidity environment in which the charge of the developer tends to decrease.

[Object of the invention]

An object of the present invention is to provide a developer for developing an electrostatic latent image as described above,
An object of the present invention is to provide an image forming apparatus, an apparatus unit, and a facsimile apparatus.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a developer, an image forming apparatus, an apparatus unit and a facsimile apparatus capable of preventing the occurrence of a fading phenomenon and forming a uniform developed image.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a developer, an image forming apparatus, an apparatus unit and a facsimile apparatus capable of preventing the occurrence of a fading phenomenon in a high-temperature and high-humidity environment and forming a uniform developed image.

[Summary of the Invention]

The present invention has a surface layer formed of a resin layer containing at least conductive fine particles and / or a solid lubricant, and has a relative load length (abbot load curve) on the surface of the surface layer. It is used in an image forming method in which a developer for developing an electrostatic latent image is transported by a developer carrier having a cutting depth C _V of 5 μm or less when t _P is 5%, and the electrostatic latent image is developed. that is an electrostatic latent image developer, the electrostatic latent image developer, the weight average particle diameter D ₄ is 10 to 15 [mu] m,
A toner having a fine powder amount (particle size of 6.35 μm or less) of 30% by number or less, a coarse powder amount (particle size of 20.2 μm or more) of 4% by weight or less, and an MI value (melt index value) of 10 or less And a developer for developing an electrostatic latent image.

Further, the present invention provides an electrostatic latent image carrier, and carries an electrostatic latent image developing developer for developing an electrostatic latent image, and transports the electrostatic latent image developing developer to a developing area. Image forming apparatus having a developing device having a developer carrying member for developing and a developer accommodating chamber accommodating a developer for developing an electrostatic latent image, wherein the developer carrying member has conductive fine particles and / or solids. has a lubricant at least the surface layer formed of a resin layer containing, Katsuteingu depth C when the relative load length t _P is 5% in the relative load curve of the surface layer (load curve of Abotsuto) _V is 5 μm or less, and the developer for developing an electrostatic latent image has a weight average particle size D ₄ of 10 to 15
μm, the amount of fine powder (particle size 6.35 μm or less) is 30% by number or less, the amount of coarse powder (particle size 20.2 μm or more) is 4% by weight or less, and the MI value (melt index value) is 10 or less The present invention relates to an image forming apparatus comprising:

Further, the invention has an electrostatic latent image carrier and a developing device for developing the electrostatic latent image, and the developing device has a developer accommodating chamber accommodating a developer for developing the electrostatic latent image. And a developer carrying member for carrying the developer for developing the electrostatic latent image and transporting the developer for developing the electrostatic latent image to the developing area, wherein the developer carrying member has conductive fine particles or / and and solid lubricant having a surface layer formed of a resin layer containing at least a relative load length t _P in the relative load curve of the surface layer (load line Abotsuto) 5% Katsuteingu depth when the Say C _V is 5
and a μm or less, the electrostatic latent image developer, the weight average particle diameter D ₄ is 10 to 15
μm, the amount of fine powder (particle size 6.35 μm or less) is 30% by number or less, the amount of coarse powder (particle size 20.2 μm or more) is 4% by weight or less, and the MI value (melt index value) is 10 or less Wherein the electrostatic device is integrally supported with a latent image developing carrier to form a unit, and forms a detachable single unit in the apparatus main body. It relates to an equipment unit.

Further, the present invention relates to an electrophotographic apparatus and a facsimile apparatus having a receiving means for receiving image information from a remote terminal, wherein the electrophotographic apparatus comprises an electrostatic latent image carrier and a developing device for developing the electrostatic latent image. A developing device, wherein the developing device is provided with a developer accommodating chamber accommodating a developer for developing the electrostatic latent image, and a developer carrying the developer for developing the electrostatic latent image and a developing region for developing the electrostatic latent image. A developer carrier for transporting the developer, the developer carrier having a surface layer formed of a resin layer containing at least conductive fine particles and / or a solid lubricant; In the relative load curve of the surface layer (abbot load curve), when the relative load length t _P is 5%, the cutting depth C _V is 5 μm or less, and the developer for developing an electrostatic latent image has a weight-average particle size. Diameter D ₄ is 10-15
μm, the amount of fine powder (particle size 6.35 μm or less) is 30% by number or less, the amount of coarse powder (particle size 20.2 μm or more) is 4% by weight or less, and the MI value (melt index value) is 10 or less The present invention relates to a facsimile apparatus, which is an image forming apparatus containing the toner.

[Specific description of the invention]

The developing device used in the image forming apparatus of the present invention will be described.

FIG. 1 is a schematic sectional view of an example of the developing device of the present invention.

Reference numeral 1 in the figure denotes a photosensitive drum that carries an electrostatic latent image and rotates in the direction of arrow A as an electrostatic latent image carrier, and may have or may not have an insulating layer on the surface. Of course, not only the drum shape but also a sheet shape and a belt shape are possible. Reference numeral 2 denotes a developing sleeve serving as a developer carrying member which carries a developer 5 containing toner on its surface and rotates in the direction of arrow B. The multi-pole permanent magnet 3 is fixed inside the sleeve 2 so as not to rotate. Have been. On the surface of the developing sleeve 2, a coating layer 10 containing conductive fine particles and / or a solid lubricant, which will be described later, has a thickness of about 0.5 μm to 30 μm.
μm (preferably, 2 μm to 20 μm). Reference numeral 4 denotes a developer storage chamber that stores the developer 5 and makes the surface of the developing sleeve 2 contact the developer 5. 6
Is a doctor blade as a member for regulating the layer of the developer 5 on the surface of the developing sleeve 2 carried in the developer accommodating chamber 4 to a predetermined thickness, and the gap between the surface of the developing sleeve 2 and the doctor blade 6 is It is arranged to be about 50 μm to 500 μm.

When the developing device configured as described above is activated and the developing sleeve 2 rotates in the direction of the arrow B, the developer storage chamber 4 is brought to the development reference potential mainly by the contact friction between the surface of the developing sleeve 2 and the toner. On the other hand, a charge having a polarity opposite to that of the electrostatic latent image on the photosensitive drum 1 is given to the toner, and is applied to the surface of the developing sleeve 2. The developer layer applied to the sleeve surface is further provided with one magnetic pole (S pole in the figure) of the multi-pole permanent magnet 3.
The layer is regulated to a uniform and thin layer (layer thickness is about 30 μm to 300 μm) by a doctor blade 6 disposed opposite to the position, and is conveyed to a developing area formed by the photosensitive drum 1 and the developing sleeve 2. You.

In the developing area, a bias such as an AC bias or a pulse bias is applied between the developing sleeve 2 and the surface of the photosensitive drum 1 so that the toner in the developer on the developing sleeve 2 flies toward the photosensitive drum. You may do so.

Here, the coating layer 10 formed on the developing sleeve surface
Will be described.

As the coating 10, a coating layer forming polymer material containing conductive fine particles and / or a solid lubricant is used.
Conductive particles, the resistance value after pressurized with 120 kg / cm ² 0.5
-What is Ωcm or less is preferable.

The conductive fine particles are preferably carbon fine particles, and the solid lubricant is preferably graphite (more preferably, crystalline graphite).

Crystalline graphite preferably used in the present invention,
It can be roughly classified into natural graphite and artificial graphite. Artificial graphite is obtained by hardening pitch coke with tar pitch or the like.
By baking once at about 00 ° C., and then placing it in a graphitization furnace and treating it at a high temperature of about 2300 ° C., carbon crystals grow and change into graphite. Natural graphite is completely graphitized by natural geothermal heat and underground high pressure for a long time, and is produced from underground. Since these graphites have various excellent properties, they have wide industrial applications. Graphite is a dark gray to black glossy, very soft, lubricious crystalline mineral that has heat resistance, chemical stability, and excellent lubricity. The crystal structure includes hexagonal and other rhombohedral, and has a complete layer structure. Regarding electrical properties, free electrons exist between carbon and carbon bonds, and are good conductors of electricity. The graphite used in the present invention may be natural or artificial.

The graphite used in the present invention has a particle size of 0.5 μm
1010 μm is preferred.

The conductive amorphous carbon is generally defined as "an aggregate of crystallites formed by burning or thermally decomposing a compound containing a hydrocarbon or carbon in an insufficient air supply". In particular, it is excellent in electric conductivity, and is widely used because it can be filled with a polymer material to impart conductivity, or a certain degree of conductivity can be obtained by controlling the amount of addition. The particle diameter of the conductive amorphous carbon used in the present invention is preferably 5 to 100 mμ, more preferably 10 to 80 mμ, and still more preferably 15 to 40 mμ.
μ is good.

The conductive fine particles and / or the solid lubricant is a resin component 10
It is preferable to use 3 to 20 parts by weight per part by weight.

When carbon fine particles and graphite particles are used in combination, it is preferable to use 1 to 50 parts by weight of carbon fine particles per 10 parts by weight of graphite.

The volume resistivity of the resin coat layer of the sleeve in which the conductive fine powder and / or the solid lubricant is dispersed is 10 ^{−6 to} 10 ^6.
Ω · cm is preferred.

Examples of the resin component that is a film-forming polymer material include styrene resins, vinyl resins, polyether sulfone resins, polycarbonate resins, polyphenylene oxide resins, polyamide resins, fluorine resins, cellulose resins, and acrylic resins. Thermoplastic resin such as resin, epoxy resin,
Polyester resin, alkyd resin, phenolic resin,
A thermosetting resin such as a melamine resin, a polyurethane resin, a urea resin, a silicon resin, a polyimide resin, or the like, a photocurable resin, or the like can be used. Among them, those with releasability such as silicone resin and fluorine resin, or those with excellent mechanical properties such as polyether sulfone, polycarbonate, polyphenylene oxide, polyamide, phenol, polyester, polyurethane and styrene resin Is more preferred. Particularly, a phenol resin is preferable.

Next, the fading phenomenon which is a problem to be solved by the present invention will be described.

When observing the sleeve when the fading phenomenon occurs, since the toner layer is formed uniformly, it is a phenomenon different from whitening due to toner shortage or the like. When the charge amount of the toner on the sleeve (hereinafter referred to as “tribo”) was measured, it was found that the value was lower than that in the normal case. That is, the toner particles that are not sufficiently charged other than the normally charged toner particles pass through the concentrated magnetic field formed by the blade 6 and the magnet 3 in FIG. To form As a result, the tribo of the toner layer is reduced, and a portion where the toner does not move on the photosensitive drum even when receiving an alternating electric field between the photosensitive drum and the sleeve occurs, and a fade phenomenon occurs. To prevent this, it is necessary to raise the tribo of the toner in the developer layer. That is, the toner is transferred to the magnetic blade 6 and the magnet 3
When passing through the concentrated magnetic field formed by the above, the concentrated magnetic field can be passed only by the reflection force acting between the toner and the sleeve, regardless of the frictional force received from the sleeve surface, a normal tribo with large reflection power The developer layer can be formed with the retained toner, and the problem of the fade phenomenon can be prevented. In order to reduce the friction on the sleeve surface and increase the slipperiness, it has been conventionally used for defining the sleeve surface roughness. By simply reducing the value of the center line average roughness Ra (hereinafter abbreviated as Ra) of the JIS standard (BO601),
A reliable effect cannot be expected. Rather, a problem such as a shortage of the coating amount of the toner in the developer on the sleeve due to the reduction of Ra causes a problem.

The sleeve of the present invention is, for example, coated on a surface of a raw tube (surface roughness 2S) after drawing of aluminum by a spraying method with a thickness of about 0.5 to 30 μm as a preparative solution as described below, and then drying oven ( The coating can be performed by a process such as thermosetting at 150 ° C).

Through the above steps, a resin-coated sleeve is produced. However, it is difficult to reduce the cutting depth C _V to 5 μm or less when the relative load length t _P = 5% by only the above-described steps. Therefore, the surface polishing of the sleeve on the resin coating layer surface of the sleeve is the last step. Is effective. For example, there is one obtained by adding a surface polishing step using felt. This polishing process will be described with an example. After the drying step, remove the coated sleeve from 800 r.p.
While rotating at about m., the felt is brought into contact with a pressure of about 1 to 3 kg. Put this felt in the longitudinal direction of the covering sleeve.
Polishing is completed by moving from one end to the other at a speed of about 5 cm / sec. The polishing method is not limited to this, and it is also possible to use a cloth, a rag, or the like, and it is also possible to directly polish by hand without rotating the sleeve. As described above, the covering sleeve used in the present invention is produced.

Next, the relative load curve of the sleeve surface will be described.

FIG. 3 shows a profile (cross-sectional curve) per reference length of the sleeve surface and a corresponding relative load curve (abbot load curve). The relative load curve is the reference length L
(2.5mm) in the profile, a level parallel to the average line of this reference length section (the distance from the highest peak of this reference length section to this level is the cutting depth C _V
), The ratio of the line sum l ₁ + l ₂ ... + L _n of the lengths of the cut lines to the reference length L and the relative length at the level (cutting depth) load say length t _P, a graph showing the relationship between the Katsuteigu depth and the relative load length is the relative load curve.

In FIG. 3, the relative load length t _P is 5%, The cutting depth at that time is C _V5 .

In this embodiment, the surface roughness measuring instrument SE-30H Kosaka Labora
Tory Ltd. was used. In the present invention, paying attention to the cutting depth C _V when the relative load length t _P is 5% in this relative load curve, C _{V is} 5 μm (preferably 0.
5 to 5 μm) to prevent the occurrence of the fading phenomenon.

Here, while the cutting depth C _V value when the relative load length t _P is 5% is related to the fading occurrence rate,
The reason why the center line average roughness Ra is not directly related to the fading occurrence rate will be described.

FIG. 4 is a profile schematically showing a part of the surface of the coated sleeve A (comparative example), in which C _V5 is 10 μm and Ra is 2.5 μm. On the other hand, the surface of the coated sleeve A was polished, and C _V5 was 1.0 μm.
Was 2.0 μm, to prepare a coated sleeve B (the present invention). FIG. 5 shows a profile schematically showing a part of the surface of the coating sleeve B.

Comparing the coated sleeves A and B, the value of C _V changed greatly from 10 μm to 1.0 μm, but Ra changed from 2.5 μm to 2.0 μm.
m has not changed much. The difference between the coated sleeves A and B is apparent when looking at the profile. C _V5 and Ra take large values because the profile of the profile is sharp because the roughness of the profile is sharp, but C _V5 is small because the profile of the profile is rounded by surface polishing. Becomes However, since the concave portion of the coating sleeve B remains as it is, Ra keeps a relatively large value. Regarding the fading phenomenon, the coating sleeve A was convex, the slipperiness of the sleeve surface was poor, and the fading phenomenon occurred. Since the convex portion was rounded, the coated sleeve B had good slipperiness on the sleeve surface, and no fading phenomenon occurred.

As described above, to improve the slip properties of the coated sleeve surface by defining the C _V5 values of the coated sleeve surface, it was found that it is possible to prevent the occurrence of Fuedeingu phenomenon.

The data for coated sleeve A and coated sleeve B are shown in the table below.

It is possible to prevent the occurrence of Fuedeingu by a C _V5 value C _V5 ≦ 5 [mu] m as described above. Also, C
_{In order to make the V5} value C _V5 ≦ 5 μm, it is effective to polish the surface of the sleeve.

As described above, Ra is not a reliable means for suppressing the occurrence of fading. However, when Ra <0.4 μm, the image density is reduced due to an insufficient amount of toner coating on the sleeve, and the developer is not uniformly charged. However, there is a tendency that an adverse effect such as generation of coat unevenness occurs. For this reason, the value of Ra is preferably Ra ≧ 0.4 μm, more preferably R
It is preferable that a ≧ 0.5 μm.

Further, it is also possible to dry-blast the surface of the sleeve coating film so as to reduce the C _V5 value of the surface of the sleeve to 5 μm or less. For example, the blasting can be performed using abrasives such as Alundum # 400 using a blasting machine manufactured by Fuji Manufacturing Co., Ltd. Further, in order to remove the fine powder of the coating film ground by the blast treatment, alcohol washing or the like can be performed together.

Next, the developer (toner) used in the present invention will be described.

The toner used in the present invention has a weight-average particle diameter based on weight.
D ₄ is 10 to 15 [mu] m (more preferably 10～13.5Myuemu) the amount of fine powder (particle size 6.35μm or less in number distribution) of 30% by number or less (more preferably, 25% or less) and coarse particles (weight It is necessary that the particle size in the distribution is 20.2 μm or more) is 4% by weight (more preferably 2% by weight or less). At the same time, the MI value of the toner used in the present invention needs to be 0.01 to 10 (more preferably 0.01 to 6).

The developer according to the present invention having the above-described configuration prevents the occurrence of a fading phenomenon particularly under high temperature and high humidity, and makes it possible to make full use of the original performance of the coat sleeve according to the present invention. Was. That is, the developer according to the present invention is a developer that can match the image forming apparatus according to the present invention very well, and can make full use of the image forming apparatus, and the developer according to the present invention and the image forming apparatus. Thus, an image forming method capable of providing a good image was established.

The present inventors, as a reason, the developer of the present invention,
In particular, even under high temperature and high humidity, the slipperiness is improved due to the regulation of C _V5 of the coated sleeve surface state having moderate hardness and particle size, that is, the force carrying capacity is suppressed and the inconvenience remains on the sleeve of the present invention. It is believed that the toner is conveyed in a sensitive manner even to slight irregularities, that is, it rolls smoothly without sticking to the sleeve surface, thereby contributing to an increase in the chance of contact charging due to the slip.

The MI value (melt index) in the present invention is:
It means a value measured by the method of JIS K-7210 at a temperature of 125 ° C. and a pressure of 10 kg.

The particle size distribution can be measured by various methods, but in the present invention, the measurement was performed using a Coulter counter.

In other words, the Coulter Counter TA is used as a measuring device.
-Type II (manufactured by Coulter), connected to an interface (manufactured by Nikkaki) and a CX-1 personal computer (manufactured by Canon) that output the number distribution and volume distribution, and using a primary sodium chloride electrolyte. Adjust 1% NaCl aqueous solution. As a measuring method, 0.1 to 5 ml of a surfactant, preferably an alkylbenzene sulfonate, is added as a dispersant to 100 to 150 ml of the aqueous electrolytic solution, and 2 to 20 mg of a measurement sample is further added. The electrolyte in which the sample was suspended was treated with an ultrasonic
Dispersion treatment for minutes, and the Coulter Counter TA-II
The volume and number of the toner were measured using a 100 μm aperture as the aperture, and the volume distribution and the number distribution of particles of 2 to 40 μm were calculated. Then, according to the present invention, the weight-average weight-average diameter determined from the volume distribution
D ₄ (the median value of each channel is the representative value for each channel), the weight-based coarse powder amount (20.2μ
m or more), the number of fines based on the number obtained from the number distribution (6.
35 μm or less).

Examples of the binder resin of the toner according to the present invention include a homopolymer of styrene such as polystyrene and polyvinyltoluene and a substituted product thereof; a styrene-propylene copolymer, a styrene-vinyltoluene copolymer, and a styrene-vinylnaphthalene copolymer. Styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-dimethylaminoethyl acrylate copolymer, styrene- Methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, styrene-dimethylaminoethyl methacrylate copolymer, styrene-vinyl methyl ether copolymer, styrene- Vinyl ethyl ether copolymer, styrene Vinyl methyl ketone copolymer, styrene - butadiene copolymer, styrene - isoprene copolymer, styrene - maleic acid copolymer, styrene - styrene copolymer and maleic acid ester copolymers;
Polymethyl methacrylate, polybutyl methacrylate, polyvinyl acetate, polyethylene, polypropylene,
Polyvinyl butyral, polyacrylic acid resin, rosin,
Modified rosin, terpene resin, phenol resin, aliphatic or alicyclic hydrocarbon resin, aromatic petroleum resin, paraffin wax, carnauba wax and the like can be used alone or in combination.

Further, as a coloring material which can be further added to the developer according to the present invention, conventionally known carbon black, copper phthalocyanine, iron black and the like can be used.

As the magnetic fine particles contained in the magnetic toner according to the present invention, a substance that is magnetized when placed in a magnetic field is used,
Powders of ferromagnetic metals such as iron, cobalt, and nickel, or alloys and compounds such as magnetite, γ-Fe ₂ O ₃ , and ferrite can be used.

These magnetic fine particles preferably have a BET specific surface area of 1 to ²⁰ m ² / g, particularly 2.5 to 12 m ² / g, and more preferably a magnetic powder having a Mohs hardness of 5 to 7 by a nitrogen adsorption method. The content of the magnetic powder is preferably from 10 to 70% by weight based on the weight of the developer.

Further, the toner of the present invention may contain a charge control agent as needed, and a negative charge control agent such as a metal complex salt of a monoazo dye, a metal complex salt of salicylic acid, an alkylsalicylic acid, a dialkylsalicylic acid or a naphthoic acid is used. .

The developer of the present invention may further contain other additives such as a lubricant such as Teflon and zinc stearate, or a fixing aid (for example, low-molecular-weight polyethylene, etc.), or a conductivity-imparting agent, as long as it does not substantially adversely affect the developer. For example, a metal oxide such as tin oxide may be added.

 Further, it is preferable to add a fluidity improver.

As the fluidity improver used in the present invention, fine powder treated with silicone oil or silicone varnish is more preferable.

The particle size of the fine powder used in the present invention is preferably in the range of 0.001 to 2 µ, and particularly preferably 0.005 to 0.2 µ. The material of the fine powder used in the present invention is preferably an inorganic compound. For example, silica, alumina, titanium oxide, etc.
Group 4 and Group 4 metal oxides are preferred.

Silica fine powder is particularly preferred.Silica fine powder includes dry silica called so-called dry method or fumed silica produced by vapor phase oxidation of a silicon halide, and so-called wet silica produced from water glass or the like. both possible is but less silanol groups on the inner surface and the fine silica powder used, and Na ₂ O, who dry silica without producing residue of SO ₃ ^2-like.

In the case of fumed silica, for example, in the manufacturing process, it is also possible to obtain a composite fine powder of silica and other metal oxides by using another metal halide such as aluminum chloride or titanium chloride together with a silicon halide, They are also included.

In the silicone oil treatment of the fine powder used in the present invention, the silanol group can be completely covered by applying the silicone oil to the surface of the fine powder, and the moisture resistance is dramatically improved.

Silicone oil or silicone varnish solids used in the present invention is generally represented by the following formula, Examples thereof include dimethyl silicone oil, alkyl-modified silicone oil, α-methylstyrene-modified silicone oil, chlorophenyl silicone oil, and fluorine-modified silicone oil. The silicone oil preferably has a viscosity at 25 ° C. of about 50 to 10
A 00 centistoke is used. Silicone oil having a molecular weight that is too low may generate volatile components due to heat treatment or the like, and if the molecular weight is too high, the viscosity becomes too high and the processing operation becomes difficult.

Known methods are used for the method of silicone oil treatment.For example, fine powder and silicone oil may be directly mixed using a mixer such as a Hensiel mixer, or a method of spraying silicone oil onto the base fine powder. Is also good. Alternatively, the varnish may be formed by mixing with a base fine powder and then removing the solvent.

Further, it is more preferable that the fine powder used in the present invention is first treated with a silane coupling agent and then treated with a silicone oil or silicone varnish.

In general, only the silicone oil treatment requires a large amount of silicone oil to cover the surface of the fine powder, which tends to cause agglomeration of the fine powder during processing, and that when applied to a developer, the fluidity of the developer may be deteriorated. It is necessary to pay close attention to the processing steps of silicone oil. Therefore, in order to remove the agglomerates of the fine powder while maintaining good moisture resistance, it is better to treat the fine powder with a silane coupling agent and then treat it with silicone oil so that the processing effect of the silicone oil can be fully exhibited. It is.

The silane coupling agent used in the present invention has a general formula R _m SiY _n R: an alkoxy group or a chlorine atom m: an integer of 1 to 3 Y: a hydrocarbon group including an alkyl group, a vinyl group, a glycidoxy group, and a methacryl group n : Represented by an integer of 3 to 1, for example, typically dimethyldichlorosilane, trimethylchlorosilane, allyldimethylchlorosilane, hexamethyldisilazane, allylphenyldichlorosilane, benzyldimethylchlorosilane, vinyltriethoxy Examples include silane, γ-methacryloxypropyltrimethoxysilane, vinyltriacetoxysilane, divinylchlorosilane, dimethylvinylchlorosilane and the like.

The silane coupling agent treatment of the fine powder is performed by a dry treatment in which the vaporized silane coupling agent is reacted with a cloud of the fine powder by stirring or the like, or the fine powder is dispersed in a solvent and the silane coupling agent is dropped. The reaction can be carried out by a generally known method such as a wet method for reaction.

Silane coupling agent, 100 parts by weight of fine powder,
The treatment is preferably performed at 1 to 50 parts by weight, more preferably 5 to 40 parts by weight.

The treatment amount of the silicone oil or silicone varnish solid in the present invention is preferably 1 to 35 parts by weight, more preferably 2 to 30 parts by weight, based on 100 parts by weight of the fine powder. The reason for limiting the above treatment amount is that if the silicone oil treatment amount is too small, the same result as that of the silane coupling agent treatment alone will not be obtained, and the moisture resistance will not be improved and the fine powder will absorb moisture under high humidity and high quality Copy images cannot be obtained. Also, if the silicone oil processing amount is too large, the above-mentioned fine powder aggregates are likely to be formed, or free silicone oil is formed, so that when applied to a developer, the flowability cannot be improved. And other drawbacks.

The amount of the processed fine powder applied to the developer is 0.01 to 20 parts by weight, more preferably 0.1 to 5 parts by weight, based on 100 parts by weight of the toner.

In the production of the toner of the present invention, the components are well kneaded by a hot kneader such as a hot roll, a kneader, an extruder, and then mechanically pulverized, obtained by classification, or dispersed in a binder resin solution. After that, a method obtained by spray drying, or a polymerization method of producing a toner by mixing a predetermined material to a monomer to constitute a binder resin to form an emulsion suspension and then polymerizing to obtain a toner, Each method can be applied.

Further, the image forming method and apparatus of the present invention will be described with reference to FIG.

The surface of the OPC photoreceptor is negatively charged by the primary charger 217, a digital latent image is formed by image scanning by exposure to laser light 705, the magnetic blade 6 and the magnet are included, and conductive fine particles and / or solids are included. The latent image is reversal-developed by a one-component magnetic developer 5 of a developing device 211 having a developing sleeve 2 covered with a resin coat layer having a lubricant containing _CV5 of 5 μm or less. In the developing section, between the conductive substrate of the photosensitive drum 1 and the developing sleeve 2, an alternating bias, a pulse bias, and / or a DC bias are applied by a bias applying unit 712. Transfer paper P
Is transferred to the transfer section, the transfer means 702 charges the transfer paper P from the back surface (the surface opposite to the photosensitive drum side) by the voltage applying means, so that the developed image (toner image) on the photosensitive drum surface is formed. The image is electrostatically transferred onto the transfer paper P. The transfer paper P separated from the photosensitive drum 1 is heated and pressed by a roller fixing device.
A fixing process is performed by 707 to fix the toner image on the transfer paper P.

The one-component developer remaining on the photosensitive drum after the transfer process is transferred to a cleaning device 708 having a cleaning blade.
Is removed by After the cleaning, the photosensitive drum 2 is gradually charged by the erase exposure 706, and the process starting from the charging process by the primary charger 217 is repeated again.

The electrostatic image carrier (photosensitive drum) has a photosensitive layer and a conductive substrate, and moves in the direction of the arrow. The non-magnetic cylindrical developing sleeve 2 serving as the toner carrier rotates in the developing section so as to advance in the same direction as the surface of the electrostatic image holding member. Inside the non-magnetic cylindrical sleeve 2, a multi-pole permanent magnet (magnet roll) as a magnetic field generating means is arranged so as not to rotate. The one-component insulating magnetic developer 5 in the developer accommodating chamber 212 of the developing device 211 is applied on a non-magnetic cylindrical surface, and the toner particles are formed by friction between the surface of the sleeve 2 having the coating layer and the toner particles. For example, a negative tribo charge is provided.
Further, the thickness of the developer layer is reduced (30 μm to 30 μm) by disposing an iron magnetic doctor blade 6 close to the cylindrical surface (interval: 50 μm to 500 μm) and opposed to one magnetic pole position of the multipole permanent magnet. The developer layer is formed so as to be non-contact with the gap between the electrostatic image carrier 1 and the developing sleeve 2 in the developing section so as to be in a non-contact state. By adjusting the rotation speed of the developing sleeve 2, the surface speed of the sleeve is substantially equal to the speed of the electrostatic image holding surface,
Or make the speed close to it. The opposed magnetic poles may be formed by using permanent magnets instead of iron as the magnetic doctor blade 6. Developing sleeve 2 in developing section
An AC bias or a pulse bias may be applied by the bias unit 712 between the power supply and the electrostatic latent image carrier. This AC bias may be such that f is 200 to 4,000 Hz and V _PP is 500 to 3,000 V.

When the toner particles are transferred in the developing section, the toner particles are transferred to the electrostatic image side due to the electrostatic force of the electrostatic image holding surface and the action of the AC bias or the pulse bias.

Instead of the magnetic doctor blade 6, an elastic blade formed of an elastic material such as silicone rubber may be used to regulate the layer thickness of the developer layer by pressing and apply the developer on the developer carrier.

When the image forming apparatus of the present invention is used as a facsimile printer, the light image exposure L is an exposure for printing received data. FIG. 7 is a block diagram showing an example of this case.

The controller 511 controls the image reading unit 510 and the printer 519. The whole controller 511 is controlled by the CPU 517. The read data from the image reading unit is sent to the transmission circuit
It is transmitted to the partner station through 513. Data received from the partner station is sent to the printer 519 through the receiving circuit 512.
Predetermined image data is stored in the image memory. The printer controller 518 controls the printer 519. 51
4 is a telephone.

The image received from the line 515 (image information from a remote terminal connected via the line) is demodulated by the receiving circuit 512, and then the CPU 517 performs a decoding process of the image information and is sequentially stored in the image memory 516. You. When at least one page of the image is stored in the memory 516, the image of the page is recorded. The CPU 517 reads out one page of image information from the memory 516 and sends the combined one page of image information to the printer controller 518. When receiving the image information of one page from the CPU 518, the printer controller 518 prints out the image information of the page.
Control 9

The CPU 517 is receiving the next page during recording by the printer 519.

 As described above, image reception and recording are performed.

As an electrophotographic apparatus, a plurality of components such as an electrostatic latent image carrier such as the above-described photosensitive drum, a developing device, and a cleaning unit are integrally connected as an apparatus unit, and this unit is used as an apparatus main body. May be configured to be detachable with respect to. For example, a unit is formed by integrally supporting at least one of the charging unit, the developing device, and the cleaning unit together with the photosensitive drum, and the unit is detachably attached to the apparatus main body. It may be configured to be detachable. At this time, the above-mentioned device unit may be provided with a charging means and / or a developing device.

Specific examples are described below, but the present invention is not limited by the following examples. In addition, the number of parts in each example is all parts by weight.

Example 1 After the above materials were uniformly mixed, they were kneaded with a two-roll mill heated to 150 ° C. for 20 minutes. After cooling the kneaded material, coarsely pulverized,
Pulverized using a fine pulverizer using a jet stream, and further classified using an air classifier, the weight average particle diameter is 11.6 μm, the amount of fine powder of 6.35 μm or less 16.0 number%, and the amount of coarse powder of 20.2 μm or more 0.4 % By weight of black fine powder (negatively chargeable magnetic toner) was obtained. The MI of this toner was 0.8.

Next, Aerosil # 200 silicate fine powder with a specific surface area of 200 m ² / g
After 100 parts (manufactured by Nippon Aerosil Co., Ltd.) are treated with 20 parts of hexamethyldisilazane (HMDS), 10 parts of dimethylsilicone oil KF-96 100cS (manufactured by Shin-Etsu Chemical) is diluted with a solvent and treated. After drying, heat-treated at about 250 ° C. to obtain negatively-charged hydrophobic silicic acid fine powder treated with dimethyl silicone oil after hexamethyldisilazane treatment,
A developer was obtained by externally adding 0.6 part to 100 parts of the toner described above.

Next, a commercially available laser beam printer LBP-SX (manufactured by Canon) was remodeled, and the surface of the developing sleeve developer carrier was
According to the method described above, Formulation 2, that is, a coating of a synthetic resin containing conductive graphite particles in a phenol resin in a ratio of 1: 1 (coating layer thickness 8 μm), and contacting the felt as described above, C _V5 = 1.0 by polishing the surface
Those with μm and Ra = 1.7 μm were set as evaluation machines for image output.

As for the developing bias, AC bias V _PP 1600V,
The frequency was 1800 Hz, and the distance between the developer carrier of the present invention and the photosensitive drum as the electrostatic latent image carrier was about 300 microns.

The above-mentioned developer is put into the above-mentioned evaluation machine, and is room temperature and normal humidity (23 ° C, 60
% RH) When 3000 continuous images were output in an environment,
A uniform image without fading was obtained. or,
When the same test was performed under high temperature and high humidity (32.5 ° C., 85% RH), similarly good results were obtained.

Example 2 The amount of fine powder having a weight average particle size of 10.3 μm and 6.35 μm or less was 24.8.
%, The amount of coarse powder of 20.2 μm or more was 0.5% by weight, and the image was produced under the same conditions as in Example 1 except that the toner of MI2 was used. Good images were obtained up to 2000 sheets.

Example 3 Amount of fine powder having a weight average particle size of 13.4 μm and a particle size of 6.35 μm or less 12.4
%, The amount of coarse powder of 20.2 μm or more is 2.0% by weight, and the toner of MI3 is used.
An image was taken out under the same conditions as in Example 1 except that C _V5 = 0.6 μm and Ra = 0.5 μm. Although the image reflection density was generally low, 2,000 sheets were obtained at room temperature and normal humidity, and the temperature was high and high. Good images were obtained up to 2000 sheets under wet conditions.

Example 4 Amount of fine powder having a weight average particle diameter of 10.0 μm and 6.35 μm or less 28.3
%, An amount of coarse powder of 20.2 μm or more, 0.8 wt%, and an image was produced under the same conditions as in Example 1 except that MI9 toner was used. An image showing slight fading development was observed, but practically Not a problem, up to 2000 sheets under normal temperature and humidity,
Almost good images were obtained up to 1000 sheets under high temperature and high humidity.

Example 5 Amount of fine powder having a weight average particle diameter of 14.7 μm and 6.35 μm or less 10.3
%, A toner with a coarse powder amount of 3.7% by weight of 20.2 μm or more and MI of 9.7, and C _V5 = 2.6 μm and Ra = 1.8 μm were changed as the evaluation machine by changing the degree of surface polishing in Example 1. When images were taken out under the same conditions as in Example 1, overall,
Although the image reflection density tends to decrease, it does not cause fading, etc. that would cause a problem in practical use,
Almost good images were obtained up to 2000 sheets and up to 1000 sheets under high temperature and high humidity.

Example 6 The developer prepared in Example 1 was supplied to the image forming apparatus shown in FIG. 6, and an image output test was performed in the same manner as in Example 1. Good results were obtained at room temperature, normal humidity and high temperature and high humidity.

 The image forming conditions are shown below.

(A) The surface of an aluminum developing sleeve used for a laser beam printer (LBP-SX) is composed of 9 parts of graphite particles (5 μm in volume average diameter), 1 part of conductive carbon particles and 10 parts of phenol resin. A coated developing sleeve with C _V5 = 0.9 μm and Ra = 1.5 μm which was coated with a material (film thickness: about 6 μm) and polished with felt was used as the developer 2 itself.

(B) A laminated OPC photosensitive drum having a diameter of 30 mm is used as the electrostatic latent image carrier 1.

(C) An iron blade is used as the blade 6, and the gap between the coating sleeve and the iron blade is set to about 250 μm.

(D) The closest distance between the covering sleeve and the OPC photosensitive drum in the developing area is set to about 300 μm.

(E) Apply an AC vise (V _PP 1600 V, frequency 1800 Hz) and a DC bias of -400 V to the coating sleeve as a developing bias.

(F) The electrostatic latent image is developed by the reversal developing method.

(G) Other settings are the same as those of the laser beam printer (LBP-SX).

As described above, when a resin layer containing at least conductive fine particles or a solid lubricant is provided on the surface thereof, and the relative load length (t _P = 5%) in the relative load curve (abt load curve) of the surface is obtained. Cutting depth C _V・ C _V 5
μm. In an image forming method using a developing device having a developer carrying member for carrying and transporting the developer,
By using the developer according to the present invention, so-called fading phenomenon can be prevented not only under normal temperature and normal humidity but also under high temperature and high humidity.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of the developing device of the present invention. FIG. 2 is a view showing a toner image for explaining the fading phenomenon. FIG. 3 is a diagram for explaining a relative load curve. 4 and 5 are diagrams schematically showing profiles on the surface of the covering sleeve. FIG. 6 is a view schematically showing a specific example of an image forming apparatus having the apparatus unit of the present invention. FIG. 7 is a block diagram showing a specific example of the facsimile apparatus. DESCRIPTION OF SYMBOLS 1 ... Electrostatic latent image carrier (photosensitive drum) 2 ... Developer carrier (sleeve) 3 ... Multipolar permanent magnet 4 ... Developer accommodating chamber 6 ... Doctor blade 7 ... Sleeve base 10 ... Coating layer

Continuation of the front page (72) Inventor Tetsuto Kuwashima 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (56) References JP-A-2-176682 (JP, A) JP-A-2-105181 ( JP, A) JP-A-1-101375 (JP, A) JP-A-59-149376 (JP, A) JP-A-52-51950 (JP, A) JP-A-2-10971 (JP, A) JP-A-2-10972 (JP, A) JP-A-62-150367 (JP, A) JP-A-64-20581 (JP, A) JP-A-64-40969 (JP, A) JP-A-1-93773 (JP) JP-A-1-276174 (JP, A) JP-A-2-73275 (JP, A) JP-A-2-204759 (JP, A) JP-A-2-236577 (JP, A) JP 59-127060 (JP, A) JP-A-61-166553 (JP, A) JP-A-63-249856 (JP, A) JP-A-63-301960 (JP, A) JP-A-59-200251 (JP, A) A) JP-A-60-4946 (JP, A) JP-A-1-219756 (JP, A) Hei 2-64556 (JP, A)

Claims (4)

(57) [Claims] 1. A surface layer formed of a resin layer containing at least conductive fine particles and / or a solid lubricant, and a relative load curve (abbot load curve) on the surface of the surface layer. Used in an image forming method in which a developer for developing an electrostatic latent image is transported by a developer carrier having a cutting depth C _V of 5 μm or less when the length t _P is 5%, and the electrostatic latent image is developed. an electrostatic latent image developer that is, the electrostatic latent image developer is 10~15μm weight average particle diameter D _4, the amount of fine powder (having a particle size 6.35μm) 30 number% or less Wherein the amount of coarse powder (powder diameter 20.2 μm or more) is 4% by weight or less and the toner contains an MI value (melt index value) of 10 or less. Developer. 2. An electrostatic latent image carrier for carrying an electrostatic latent image developing developer for developing an electrostatic latent image and transporting the electrostatic latent image developing developer to a developing area. An image forming apparatus having a developing device having a developer carrier and a developer accommodating chamber accommodating a developer for developing an electrostatic latent image, wherein the developer carrier contains conductive fine particles or / and a solid lubricant. A surface layer formed of at least a contained resin layer, and a relative load curve (abbot load curve) of the surface layer
The cutting depth C _V when the relative load length t _P is 5% is 5 μm or less, and the developer for developing an electrostatic latent image has a weight average particle diameter D _{4 of 10} to 15 μm.
m, the amount of fine powder (particle size 6.35 μm or less) is 30% by number or less, the amount of coarse powder (particle size 20.2 μm or more) is 4% by weight or less, and the MI value (melt index value) is 10 or less An image forming apparatus comprising: 3. An electrostatic latent image carrier and a developing device for developing an electrostatic latent image, the developing device being in static contact with a developer accommodating chamber accommodating an electrostatic latent image developing developer. A developer carrying member for carrying the developer for developing the electrostatic latent image and transporting the developer for developing the electrostatic latent image to the developing area, wherein the developer carrying member has conductive fine particles and / or solid lubricant. Having a surface layer formed of a resin layer containing at least an agent, and a relative load curve (abbot load curve) of the surface layer
The cutting depth C _V when the relative load length t _P is 5% is 5 μm or less, and the developer for developing an electrostatic latent image has a weight average particle diameter D _{4 of 10} to 15 μm.
The amount of fine powder (particle size 6.35 μm or less) is 30% by number or less, the amount of coarse powder (particle size 20.2 μm or more) is 4% by weight or less, and the MI value (melt index value) is 10 or less. A developing unit which contains a toner and is integrally supported with the electrostatic latent image carrier to form a unit, and forms a detachable single unit in the apparatus main body. Unit. 4. A facsimile apparatus having an electrophotographic apparatus and a receiving means for receiving image information from a remote terminal, wherein the electrophotographic apparatus includes an electrostatic latent image carrier and a developing device for developing the electrostatic latent image. The developing device has a developer accommodating chamber for accommodating the developer for developing an electrostatic latent image, carries the developer for developing the electrostatic latent image, and transports the developer for developing the electrostatic latent image to a developing area. And a developer carrier having a surface layer formed of a resin layer containing at least conductive fine particles and / or a solid lubricant. Load curve (abbot load curve)
The cutting depth C _V when the relative load length t _P is 5% is 5 μm or less, and the developer for developing an electrostatic latent image has a weight average particle diameter D _{4 of 10} to 15 μm.
m, the amount of fine powder (particle size 6.35 μm or less) is 30% by number or less, the amount of coarse powder (particle size 20.2 μm or more) is 4% by weight or less, and the MI value (melt index value) is 10 or less A facsimile apparatus characterized in that the facsimile apparatus is an image forming apparatus containing the toner as described above.