JP3416412B2 - Toner 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 toner used in a recording method using an electrophotographic method, an electrostatic recording method, a magnetic recording method and the like, and an image forming method. More specifically, the present invention relates to a toner and an image forming method used in a copying machine, a printer, and a fax, in which a toner image is previously formed on an electrostatic latent image carrier and then transferred onto a transfer material to form an image.

[0002]

2. Description of the Related Art Conventionally, a large number of electrophotographic methods are known, but generally, a photoconductive substance is used and an electric latent image is formed on an image bearing member (photoreceptor) by various means. After forming the latent image, the latent image is developed with toner to form a visible image, and the toner image is transferred to a transfer material such as paper as necessary, and then the toner image is fixed on the transfer material by heat or pressure. To obtain a copy.

As a method for visualizing an electric latent image, a cascade developing method, a magnetic brush developing method, a pressure developing method and the like are known. Further, there is also used a method in which a magnetic toner is used and a rotating sleeve having a magnetic pole at the center is used to fly between the photosensitive member and the sleeve by an electric field.

Unlike the two-component system, the one-component developing system does not require carrier particles such as glass beads and iron powder, and therefore the developing device itself can be made compact and lightweight. Further, since the two-component developing system needs to keep the toner concentration in the carrier constant, a device for detecting the toner concentration and supplying a required amount of toner is required. Therefore, also in this case, the developing device becomes large and heavy. Such a device is not necessary in the one-component developing system, and it is preferable because it can be made small and light.

In addition, LED and LBP printers have become the mainstream of the market in recent years as the printer apparatus, and the direction of technology is higher resolution, that is, 400, 600, 800 dpi instead of 240, 300 dpi in the past. ing. Therefore, the developing system is also required to have higher definition. Further, the copiers are also becoming more sophisticated, and as a result, they are moving toward digitalization. In this direction, the method of forming an electrostatic charge image by a laser is mainly used, and therefore, it is also advancing toward high resolution, and here also, as in the case of a printer, a high resolution / high definition developing method is required. . For this reason, the particle size of the toner is being reduced, and it is disclosed in Japanese Patent Laid-Open Nos. 1-112253 and 1-1.
No. 91156, No. 2-214156, No. 2-284158, No. 3-181952.
Japanese Patent Application Laid-Open No. 4-162048 and Japanese Patent Application Laid-Open No. 4-162048 propose a toner having a specific particle size distribution and a small particle size.

The toner image formed on the photoconductor in the developing process is transferred to the transfer material in the transfer process, but the transfer residual toner remaining on the photoconductor is cleaned in the cleaning process.
Toner is stored in the waste toner container. For this cleaning process, blade cleaning, fur brush cleaning, roller cleaning, etc. have been conventionally used. From the viewpoint of the apparatus, the size of the apparatus is inevitably increased due to the provision of such a cleaning apparatus, which has been a bottleneck when aiming to make the apparatus compact. Further, from the viewpoint of ecology, a system with less waste toner is desired in terms of effective utilization of toner, and a toner with good transfer efficiency has been demanded.

Japanese Patent Application Laid-Open No. 61-279864 proposes toners having shape factors SF-1 and SF-2. However, there is no description regarding transfer in this publication, and as a result of carrying out Examples, transfer efficiency is low and further improvement is required.

Further, Japanese Patent Application Laid-Open No. 63-235953 proposes a magnetic toner spherically shaped by a mechanical impact force. However, the transfer efficiency is still insufficient and further improvement is needed.

Further, Japanese Patent Application Laid-Open No. 2-61649, Japanese Patent Application Laid-Open No. 2-77756, and Japanese Patent Application Laid-Open No. 4-328757 propose toners to which inorganic fine particles are fixed. However, there is no description of transfer in this publication, and as a result of carrying out the examples, the transfer efficiency is insufficient and further improvement is necessary.

Further, in recent years, from the viewpoint of environmental protection, the primary charging and transfer processes using corona discharge, which have been conventionally used, are becoming mainstream, and the primary charging and transfer processes using a photoconductor contact member are becoming mainstream.

For example, JP-A-63-149669 and JP-A-2-123385 have been proposed. These are related to the contact charging method and the contact transfer method, but a conductive elastic roller is brought into contact with the electrostatic latent image carrier,
While electrostatically charging the electrostatic latent image carrier while applying a voltage to the conductive roller, another voltage was applied to the electrostatic latent image carrier after obtaining a toner image by exposure and development steps. While transferring the transfer material while pressing the conductive roller to transfer the toner image on the electrostatic latent image bearing member onto the transfer material, a transfer image is obtained through a fixing step.

However, in such a roller transfer system which does not use corona discharge, since the transfer member is brought into contact with the photoconductor through the transfer member during transfer, the toner image formed on the photoconductor is transferred to the transfer material. When the toner image is transferred to the toner image, the toner image is brought into pressure contact with the toner image, which causes a problem of partial transfer failure, which is so-called void in transfer (see FIG. 7B).

Further, as the diameter of the toner becomes smaller, the adhesion force of the toner particles (image force, van der Waals force, etc.) to the photoconductor becomes larger than the Coulomb force applied to the toner particles by the transfer. As a result, the transfer residual toner tends to increase.

Further, when the particle size of the toner becomes small, the amount of fine powder having a high charge amount increases and it becomes easy to fill the latent image electric field with a small amount of toner. The toner having a large amount of fine particles is particularly excellent in reproducibility of one minute dot of a digital latent image, but tends to have an insufficient image density or a large amount of fog. In particular, in printing on a large number of sheets in a low humidity environment, there is a problem in that fine particles tend to accumulate on the surface of the toner carrier, causing a so-called charge-up phenomenon. This is because the charge amount of the toner coated on the toner carrier becomes too high due to the contact with the toner carrier as the toner carrier repeatedly rotates, and the toner mirrors the surface of the toner carrier. This is a phenomenon in which they are attracted by force, become immobile on the surface of the toner carrier, and do not move from the toner carrier to the latent image on the latent image carrier (drum). When such a phenomenon occurs, the toner in the upper layer is less likely to be charged, and the developing amount of the toner decreases, so that a low-quality image such as a thin line image, a reduced image density of a solid image, or an increase in fog is generated. Become. Furthermore, since the toner layer forming state of the image portion (toner consuming portion) and the non-image portion are different and the charging state is different, the position where the solid image with high image density is once developed is the next rotation of the toner carrier. Sometimes, when a halftone image is developed at the developing position and developed, a phenomenon that a trace of a solid image appears on the image, that is, a so-called toner carrier ghost phenomenon easily occurs.

Further, in recent years, there has been a tendency to lower the toner fixing temperature for the purpose of shortening the warm-up time and saving the power of the printer body. The toner having such a fine particle diameter and low-temperature fixing property is more likely to be electrostatically attached to the toner carrier, and is subjected to physical force from the outside to cause contamination of the toner carrier surface or toner Fusion is likely to occur. In addition, with the increasing awareness of resource saving, it is required to further reduce the toner consumption amount (the amount of toner used to form one image).

Further, in the roller charging method, the physical and chemical action of the surface of the electrostatic latent image bearing member due to the discharge generated between the charging roller and the electrostatic latent image bearing member is larger than that in the corona charging method. In particular, in the combination with the organic photoconductor / blade cleaning, abrasion due to deterioration of the photoconductor surface is likely to occur, and there is a problem in life (direct charging /
The combination of the organic photoreceptor / one-component magnetic developing method / contact transfer / blade cleaning makes it easy to reduce the cost and size and weight of the image forming apparatus. This is the mainstream method for printers, facsimiles, etc. ).

Therefore, it has been required that the toner and the photoconductor used in such an image forming method have excellent releasability.

[0018]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a toner and an image forming method which solve the above problems of the prior art.

That is, the object of the present invention is to provide excellent transferability,
An object of the present invention is to provide a toner and an image forming method in which the amount of residual toner after transfer is small and voids in transfer do not occur even in a roller transfer system, or these phenomena are suppressed.

Further, an object of the present invention is to provide a toner and an image forming method in which the toner is not fused or contaminated on the toner carrier, and excellent transferability can be stably obtained for a long period of time and after printing a large number of sheets. To do.

Another object of the present invention is to provide a toner and an image forming method which are excellent in mold releasability and slipperiness, have little abrasion even after a long period of time and after printing a large number of sheets, and have a long life. It is in.

Another object of the present invention is to provide a toner and an image forming method in which abnormal charging or image defects due to contamination of a member pressed against an electrostatic latent image carrier does not occur, or these phenomena are suppressed. It is in.

[0023]

Means for Solving the Problems The present invention, the substrate and low
At least particles for imparting roughness to the surface of the toner carrier
It has a coating layer containing a conductive substance and a binder resin, the surface
The toner layer thickness regulating member made of an elastic member is brought into contact with the toner carrier having a center line average roughness of 0.2 to 4.5 μm.
Was to form a thin layer of toner, a toner used in an image forming method for developing an electrostatic electrostatic image on the latent image bearing member while applying an alternating electric field to the toner in the developing unit, the toner is, A toner having at least toner particles in which a colorant is dispersed in a binder resin and an inorganic fine powder, and the shape factor SF-1 of the toner measured by an image analyzer is 11
0 <SF-1 ≦ 180, the value of the shape factor SF-2 is 110 <SF-2 ≦ 140, and the value of SF-2 is 1
The ratio B / A of the value B obtained by subtracting 00 and the value A obtained by subtracting 100 from the value of SF-1 is 1.0 or less, and the specific surface area per unit volume of the toner measured by the BET method. Specific surface area St per unit volume calculated from Sb (m ² / cm ³ ) and the weight average particle diameter when the toner is assumed to be a true sphere
The relationship of (m ² / cm ³ ) satisfies the following conditions 3.0 ≦ Sb / St ≦ 7.0 Sb ≧ St × 1.5 + 1.5 , and the toner particles have a fine particle size of 1 to 100 nm.
60% pore radius in the integrated pore area ratio curve of pores
3.5nm an image forming method using the toner and the toner, wherein less der Rukoto. In the following,
The "present invention 1" especially means the toner or the image forming method having the above-mentioned configuration.

Furthermore, the present invention is a toner in which a colorant is dispersed in at least a binder resin, and toner particles having an inorganic fine powder 1 adhered to the surface thereof and an inorganic fine powder 2 are externally mixed. The value of the shape factor SF-1 measured by the image analyzer of the toner is 110 <SF-1 ≦ 180, the value of the shape factor SF-2 is 110 <SF-2 ≦ 140, and the value of SF-2. The ratio B / A of the value B obtained by subtracting 100 to the value A obtained by subtracting 100 from the value of SF-1 is 1.0.
Below, the specific surface area Sb (m ² / cm ³ ) per unit volume of the toner measured by the BET method and the ratio per unit volume calculated from the weight average particle diameter when the toner is assumed to be a true sphere. The relationship of the surface area St (m ² / cm ³ ) satisfies the following conditions 3.0 ≦ Sb / St ≦ 7.0 Sb ≧ St × 1.5 + 1.5, and the toner has a weight average particle diameter of 4 to 8 μm
And the ratio of toner particles having a particle size of more than 10 μm is 0.9 to
The present invention relates to a toner characterized by being 4.8% by volume and an image forming method using the toner. In the following, the “present invention 2” especially means the toner or the image forming method having the above-mentioned configuration.

[0025]

BEST MODE FOR CARRYING OUT THE INVENTION The shape factor of the toner in the present invention is more preferably such that the value of SF-1 is 120≤SF-1≤.
160, and the value of SF-2 is 115 ≦ SF-2 ≦
A toner of 140 is used.

In the present invention, SF-indicating the shape factor
1 and SF-2 are, for example, Hitachi FE-SEM
(S-800) is used to randomly sample 100 toner images of 2 μm or more magnified 1000 times, and the image information is introduced into an image analysis device (Luzex III) manufactured by Nicolet Co., Ltd. through an interface. The value obtained by performing the analysis and calculating from the following equation is used as the shape factor SF-1, S
It is defined as F-2.

[0027]

[Equation 1]

(Where MXLNG is the absolute maximum length of the particle,
PERIME represents the perimeter of the particle, and AREA represents the projected area of the particle. )

The shape factor SF-1 indicates the degree of roundness of the toner particles, and the shape factor SF-2 indicates the degree of unevenness of the toner particles.

When the toner shape factor SF-1 is 110 or less, or when the toner spherical factor SF-2 is 110 or less, and the value B and SF− obtained by subtracting 100 from the value of SF-2.
The value of the ratio B / A with the value A obtained by subtracting 100 from the value of 1 is 1.
When it exceeds 0, cleaning failure generally tends to occur, and when the toner shape factor SF-1 exceeds 180,
The toner particles are separated from the spherical shape and approach an irregular shape, the toner is easily crushed in the developing device, the particle size distribution is fluctuated, the charge amount distribution is broad, and the background fog and the reverse fog are easily generated.
On the other hand, if SF-2 exceeds 140, the transfer efficiency of the toner image at the time of transfer from the electrostatic latent image carrier (photoreceptor) to the transfer material is reduced, and character or line image dropout occurs undesirably. . At this time, the toner manufactured by the pulverization method is preferably used.

Further, B / A represents the slope of a straight line passing through the origin in FIG. 6, and the ratio of B / A is preferably 1.0 or less, more preferably 0.2 to 0.9 ( Further, it is preferably 0.35 to 0.85) in order to improve transferability while maintaining developability.

Further, by having the inorganic fine powder on the surface of the toner particles, the transfer efficiency is improved and the voids in the transfer of characters and line images are improved. At this time, the specific surface area Sb per unit volume measured by the BET method and the specific surface area St per unit volume (St = 6 / calculated from the weight average particle diameter (D ₄ ) assuming that the toner is a true sphere. D ₄ ) is 3.0 ≦ Sb / St ≦ 7.0 and Sb ≧ St ×
It is preferably 1.5 + 1.5, and further, Sb is 3.2 to 6.8 m ² / cm ³ (more preferably 3.4 to
It is preferably 6.3 m ² / cm ³ ).

If the ratio is less than 3.0 times, the transfer efficiency is insufficient, and if it exceeds 7.0 times, the image density is lowered. It is considered that this is because the inorganic fine particles added to the toner particles behave effectively as a spacer between the toner particles and the toner image carrier.

The specific surface area of the toner within the above range can be achieved by controlling the specific surface area of the toner particles, the specific surface area of the inorganic fine powder added to the toner particles, the addition amount and the addition mixing strength.

Further, since the inorganic fine powder is effectively used, the specific surface area Sr per volume of the toner particles is 1.2 to.
2.5m ² / cm ³ (preferably 1.4~2.1m ² / c
m ³ ), which is 1.5 to the theoretical specific surface area per volume calculated from the weight average particle diameter assuming that the toner is a true sphere.
It is good to be 2.5 times.

Further, the addition of the inorganic fine powder preferably increases the specific surface area by 1.5 m ² / cm ³ or more. At this time, the BET specific surface area Sb of the toner and the BE of the toner particles are
The value of the ratio Sb / Sr of the T specific surface area Sr is preferably in the range of 2-5.

In the first aspect of the present invention, the addition and mixing strength of the toner particles and the inorganic fine powder should not be too strong so that the inorganic fine powder is not embedded in the toner particles. In addition, the present invention 1
Then, from 1 nm of the toner particles before adding the inorganic fine powder
60 in the integrated pore area ratio curve of 100 nm pores
% Pore radius Ru der less than 3.5nm. It is considered that the inorganic fine powder behaves more effectively and the transfer efficiency is improved by reducing the pores in the toner particles which are larger than the primary particle diameter of the inorganic fine powder added to the toner particles. .

The specific surface area was determined according to the BET method by adsorbing nitrogen gas on the sample surface using a specific surface area measuring device Autosorb 1 (manufactured by Yuasa Ionics) and calculating the specific surface area using the BET multipoint method. Further, the 60% pore radius was calculated from the integrated pore area ratio curve with respect to the desorption side pore radius. In Autosorb 1, the pore size distribution is calculated by Bar
rett, Joyner & Harenda (B.
J. H.). J. The H method is used.

The present invention is characterized in that after the inorganic fine powder is fixed to the surface of the toner particles, the inorganic fine powder is externally added and mixed. In the second aspect of the present invention, the inorganic fine powder adhered to the toner surface makes the releasability effect last longer, and the presence of a small amount of the externally added and mixed inorganic fine powder improves the fluidity of the magnetic toner. Due to the synergistic effect of both, excellent developability and high transferability can be obtained for a long period of time.

In the present invention, in order to faithfully develop finer latent image dots for higher image quality, the toner particles preferably have a weight average diameter of 4 μm to 8 μm. In the case of toner particles having a weight average particle diameter of less than 4 μm, a large amount of residual toner remains on the photosensitive member due to a decrease in transfer efficiency, and moreover, it tends to cause uneven image unevenness due to fog and transfer failure. It is not preferable for the toner to be used. Further, when the weight average diameter of the toner particles exceeds 8 μm, scattering of characters and line images is likely to occur.

For the average particle size and particle size distribution of the toner, a Coulter Counter TA-II type or a Coulter Multisizer (manufactured by Coulter) is used, and an interface (manufactured by Nikkaki) for outputting number distribution and volume distribution and PC9.
801 personal computer (manufactured by NEC) is connected, and the electrolyte is 1% NaCl using primary sodium chloride.
Prepare an aqueous solution. For example, ISOTON R-II
(Manufactured by Coulter Scientific Japan) can be used. As the measuring method, the electrolytic aqueous solution 100 to 1 is used.
0.1 to 5 ml of a surfactant (preferably alkylbenzene sulfonate) as a dispersant is added to 50 ml,
Further, 2 to 20 mg of the measurement sample is added. The electrolytic solution in which the sample was suspended was subjected to dispersion treatment for about 1 to 3 minutes by an ultrasonic disperser, and the volume and number of toner particles having a size of 2 μm or more were measured using a 100 μm aperture as an aperture with the Coulter Counter TA-II type. The volume distribution and number distribution were calculated. Then, the volume-based weight average particle diameter (D ₄ ) obtained from the volume distribution and the number-based length average particle diameter (D ₁ ) obtained from the number distribution according to the present invention were obtained.

The charge amount per unit volume (two-component method) of the toner according to the present invention is 30 to 80 C / m ³ (more preferably 40 to 70 C / m ³ ). It is preferable for improving transfer efficiency in a transfer method using a member.

The method for measuring the charge amount (two-component tribo) of the toner by the two-component method in the present invention is shown below (FIG. 5).

Using an EFV200 / 300 (manufactured by Powder Tech) as a carrier in an environment of 23 ° C. and 60% relative humidity, a mixture of 9.5 g of carrier and 0.5 g of toner was added to a polyethylene bottle having a capacity of 50 to 100 ml. Shake by hand 50 times. Next, 1.0 to 1.2 g of the mixture is put into a metal measuring container 22 having a 500-mesh screen 23 on the bottom, and a metal lid 24 is placed. At this time, the total mass of the measurement container 22 is weighed and set as W ₁ (g). Next, in the suction device (at least the portion in contact with the measurement container 22 is an insulator), suction is performed from the suction port 27 and the air flow rate control valve 26 is adjusted to adjust the pressure of the vacuum gauge 25 to 2450 Pa (25
0 mmAq). In this state, suction is performed for 1 minute to remove the toner by suction. The potential of the electrometer 29 at this time is V
(Bolt). Here, 28 is a capacitor, and the capacitance is C (μF). Further, the mass of the entire measuring machine after suction is weighed and designated as W ₂ (g). Triboelectric charge amount of this toner (m
C / kg) is calculated by the following formula.

Triboelectric charge amount (mC / kg) = CV / (W ₁ −W ₂ ).

In the GPC molecular weight distribution, the binder resin used in the toner according to the present invention has a ratio (Mw / Mw) of the weight average molecular weight (Mw) to the number average molecular weight (Mn).
Resins having Mn) of 2 to 100 are preferred for the present invention.
A resin having two or more molecular weight distribution peaks in GPC molecular weight distribution is also suitably used in the present invention. Further, in the GPC molecular weight distribution, a resin having a ratio of a molecular weight of 2,000 or less of 10% or less and a ratio of a molecular weight of more than 1,000,000 of 20% or less is particularly preferable for the present invention.

The molecular weight is measured by GPC (gel permeation chromatography). Concrete GP
As a method of measuring C, a sample obtained by previously extracting the toner with a Soxhlet extractor for 20 hours using a THF (tetrahydrofuran) solvent was used, and the column configuration was A-801, 802, 803, 804, 805, 80 manufactured by Showa Denko.
6,807 can be connected and the molecular weight distribution can be measured using the calibration curve of standard polystyrene resin.

The glass transition point Tg of the toner is preferably 50 ° C. to 75 ° C. (more preferably 52 ° C. to 70 ° C.) from the viewpoints of fixability and storability.

Glass transition point Tg of the toner according to the present invention
For example, DSC- manufactured by Perkin Elmer Co., Ltd.
The measurement is performed with a highly accurate internal heat input compensation type differential scanning calorimeter such as 7. The measuring method is ASTM D3418-8.
Perform according to 2. In the present invention, the sample is heated once to take a previous history, then rapidly cooled, and then again at a temperature rate of 10 ° C./m.
In, a DSC curve measured when the temperature is raised in the range of 0 to 200 ° C. is used.

The type of the binder resin used in the present invention is, for example, a homopolymer of styrene such as polystyrene, poly-p-chlorostyrene, polyvinyltoluene, or a substitute thereof; styrene-p-chlorostyrene copolymerization. Coal, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-acrylic acid ester copolymer, styrene-methacrylic acid ester copolymer, styrene-α-chloromethyl methacrylate copolymer, styrene- Acrylonitrile copolymer, styrene-vinyl methyl ether copolymer, styrene-vinyl ethyl ether copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile- Styrene-based copolymers such as indene copolymers Combined; polyvinyl chloride, phenol resin, natural modified phenol resin, natural resin modified maleic acid resin, acrylic resin, methacrylic resin, polyvinyl acetate, silicone resin, polyester resin, polyurethane, polyamide resin, furan resin, epoxy resin, xylene resin , Polyvinyl butyral, terpene resin, coumarone indene resin, petroleum resin and the like can be used. A crosslinked styrene resin is also a preferable binder resin.

Examples of the comonomer for the styrene monomer of the styrene type copolymer include acrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate,
Didecyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, phenyl acrylate, methacrylic acid, methyl methacrylate, ethyl methacrylate, butyl methacrylate, octyl methacrylate, octyl methacrylate, acrylonitrile, methacrylonitrile, acrylamide, etc. A monocarboxylic acid having a heavy bond or a substituted product thereof;
For example, a dicarboxylic acid having a double bond such as maleic acid, butyl maleate, methyl maleate, dimethyl maleate, and the like; and substituted compounds thereof; for example, vinyl chloride,
Vinyl esters such as vinyl acetate, vinyl benzoate, etc., ethylene-based olefins such as ethylene, propylene, butylene, etc .; vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone, etc .;
For example, vinyl ethers such as vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether and the like; and vinyl monomers such as are used alone or in combination. Here, as the cross-linking agent, a compound having two or more polymerizable double bonds is mainly used, and examples thereof include aromatic divinyl compounds such as divinylbenzene and divinylnaphthalene; for example, ethylene glycol diacrylate and ethylene glycol. Dimethacrylate,
A carboxylic acid ester having two double bonds such as 1,3-butanediol dimethacrylate; a divinyl compound such as divinylaniline, divinyl ether, divinyl sulfide, divinyl sulfone; and a compound having three or more vinyl groups; Can be used alone or as a mixture.

As the binder resin for toner used for pressure fixing, low molecular weight polyethylene, low molecular weight polypropylene, ethylene-vinyl acetate copolymer, ethylene-acrylic acid ester copolymer, higher fatty acid, polyamide Resin and polyester resin may be used. These are preferably used alone or in combination.

Further, it is also preferable to include the following waxes in the toner from the viewpoint of improving the releasability from the fixing member during fixing and the fixing property. Paraffin wax and its derivatives, microcrystalline wax and its derivatives, Fischer-Tropsch wax and its derivatives, polyolefin wax and its derivatives, carnauba wax and its derivatives, etc., where the derivatives are oxides and block copolymers with vinyl monomers. , Including graft modified products.

In addition, alcohols, fatty acids, acid amides,
Esters, ketones, hydrogenated castor oil and its derivatives, plant wax, animal wax, mineral wax, petrolactam and the like can also be used.

In the toner of the present invention, it is preferable to use a charge control agent in the toner particles (internal addition) or in the mixture with the toner particles (external addition). The charge control agent makes it possible to control the optimum charge amount according to the development system.
Particularly in the present invention, it is possible to make the balance between the particle size distribution and the charge amount more stable. The following substances control the toner to be negatively charged.

Organic metal complexes and chelate compounds are effective, for example, monoazo metal complexes, acetylacetone metal complexes, aromatic hydroxycarboxylic acids, and aromatic dicarboxylic acid type metal complexes. Other examples include aromatic hydroxycarboxylic acids, aromatic mono- and polycarboxylic acids and their metal salts, anhydrides, esters, and phenol derivatives such as bisphenol.

Further, there are the following substances for controlling the positive charge property.

Modified products of nigrosine and fatty acid metal salts and the like; quaternary ammonium salts such as tributylbenzylammonium-1-hydroxy-4-naphthosulfonate, tetrabutylammonium tetrafluoroborate, and phosphonium salts which are analogs thereof. Onium salts and lake pigments thereof, triphenylmethane dyes and lake pigments thereof (as a laker, phosphotungstic acid, phosphomolybdic acid, phosphotungstic molybdic acid, tannic acid, lauric acid, gallic acid, ferricyanide) Compounds, ferrocyanides, etc.), metal salts of higher fatty acids; diorganotin oxides such as dibutyltin oxide, dioctyltin oxide, dicyclohexyltin oxide; dibutyltin borate, dioctyltin borate, dicyclohexyl Diorgano tin borate such as Suzuboreto; can be used in combination singly or two or more kinds.

The charge control agents described above are preferably used in the form of fine particles, and in this case, the number average particle diameter of these charge control agents is preferably 4 μm or less, more preferably 3 μm or less. When these charge control agents are internally added to the toner, it is preferable to use 0.1 to 20 parts by mass, particularly 0.2 to 10 parts by mass with respect to 100 parts by mass of the binder resin.

As the colorant used in the present invention, carbon black, a magnetic substance, or a yellow / magenta / cyan colorant shown below, which is toned black, is used.

As the yellow colorant, condensed azo compounds, isoindolinone compounds, anthraquinone compounds,
Compounds represented by azo metal complexes, methine compounds and allylamide compounds are used. Specifically, C.I. I. Pigment Yellow 12, 13, 14, 15, 17, 6
2, 74, 83, 93, 94, 95, 97, 109, 1
10, 111, 120, 127, 128, 129, 14
7, 168, 174, 176, 180, 181, 191
Etc. are preferably used.

As the magenta colorant, a condensed azo compound, a diketopyrrolopyrrole compound, an anthraquinone, a quinacridone compound, a basic dye lake compound, a naphthol compound, a benzimidazolone compound, a thioindigo compound, and a perylene compound are used. Specifically, C.I.
I. Pigment Red 2, 3, 5, 6, 7, 23, 4
8; 2, 48; 3, 48; 4, 57; 1, 81; 1, 1
44, 146, 166, 169, 177, 184, 18
5,202,206,220,221,254 are particularly preferred.

As the cyan colorant, a copper phthalocyanine compound and its derivative, an anthraquinone compound, a basic dye lake compound and the like can be used. Specifically, C.I. I.
Pigment Blue 1, 7, 15, 15: 1, 15: 2,
15: 3, 15: 4, 60, 62, 66 and the like can be used particularly preferably.

These colorants may be used alone or in a mixture, and may be used in the state of solid solution. The colorant of the present invention is selected in terms of hue angle, saturation, lightness, weather resistance, OHP transparency, and dispersibility in the toner. The amount of the colorant added is 1 to 20 parts by mass based on 100 parts by mass of the resin.

When a magnetic substance is used as the black colorant, unlike other colorants, the amount is 30 with respect to 100 parts by mass of the resin.
It is used by adding up to 200 parts by mass.

Examples of the magnetic substance include metal oxides containing elements such as iron, cobalt, nickel, copper, magnesium, manganese, aluminum and silicon. Of these, those containing iron oxide as a main component, such as ferrosoferric oxide and γ-iron oxide, are preferable. Further, from the viewpoint of controlling the toner chargeability, other metal elements such as silicon element or aluminum element may be contained. These magnetic particles are B-based by the nitrogen adsorption method.
ET specific surface area is preferably 2 to 3 m ² / g, especially 3 to 28
A magnetic powder having m ² / g and a Mohs hardness of 5 to 7 is preferable.

The shape of the magnetic material is octahedron, hexahedron,
There are spheres, needles, scales, etc., but those having little anisotropy such as octahedrons, hexahedrons, spheres, and irregular shapes are preferable for increasing the image density. The average particle size of the magnetic substance is 0.05 to
1.0 μm is preferable, and 0.1 to 0.
6 μm, and more preferably 0.1 to 0.4 μm.

The amount of magnetic material is 3 with respect to 100 parts by mass of the binder resin.
0 to 200 parts by mass, preferably 40 to 200 parts by mass, and more preferably 50 to 150 parts by mass. If the amount is less than 30 parts by mass, in a developing device that uses magnetic force for toner transportation, the transportability is insufficient and the developer layer on the developer carrier tends to become uneven, resulting in image unevenness. The image density tends to decrease due to the above. On the other hand, if the amount exceeds 200 parts by mass, the fixing property tends to have a problem.

As the inorganic fine powder contained in the toner of the present invention, known ones may be used. To improve the charging stability, developability, fluidity and storage stability, silica, alumina,
It is preferably selected from titania and its complex oxides. Furthermore, silica is more preferable. For example, as the silica, both a so-called dry method produced by vapor phase oxidation of a silicon halide or an alkoxide or a dry silica called fumed silica and a so-called wet silica produced from alkoxide, water glass, etc. can be used. However, dry silica having less silanol groups on the surface and inside the fine silica powder and less production residues such as Na ₂ O and SO ₃ ²⁻ is preferable. Further, in the case of dry silica, it is also possible to obtain a composite fine powder of silica and other metal oxide by using other metal halogen compound such as aluminum chloride and titanium chloride together with the silicon halogen compound in the manufacturing process. Also includes.

[0070] The present invention in the inorganic fine powder used is preferably a primary particle diameter of 30nm or less, the specific surface area by further nitrogen adsorption measured by BET method is 30 m ² / g or more, particularly 50 to 400 m ² / g The range of 3 gives good results, and 0.1 to 8 parts by mass of fine silica powder, preferably 0.5 to 5 parts by mass, more preferably more than 1.0 and more than 3. It is particularly preferable to use up to 0 parts by mass. Yes.

The inorganic fine powder used in the present invention is
Silicone varnishes, various modified silicone varnishes, silicone oils, various modified silicone oils, silane coupling agents, silane coupling agents having functional groups, other organic silicon compounds, organics for the purpose of hydrophobicizing, controlling chargeability, etc. It is also possible and preferable to treat with a treating agent such as a titanium compound or in combination with various treating agents.

In order to maintain a high charge amount, achieve a low consumption amount and a high transfer rate, it is more preferable that the inorganic fine powder is treated with at least silicone oil.

Further, in the present invention, transferability and / or
Alternatively, in order to improve the cleaning property, in addition to the inorganic fine powder, the primary particle diameter is more than 30 nm (preferably the specific surface area is less than 50 m ² / g), more preferably 5
0 nm or more (preferably specific surface area less than 30 m ² / g)
It is also one of the preferable modes to further add the inorganic or organic spherical particles. For example, spherical silica particles, spherical polymethylsilsesquioxane particles, spherical resin particles and the like are preferably used. The primary particle size of these fine particles is measured from an electron micrograph.

In the toner of the present invention, other additives, for example, Teflon powder, zinc stearate powder, polyvinylidene fluoride powder, lubricant powder; cerium oxide powder, silicon carbide Powder,
Abrasives such as strontium titanate powder; fluidity-imparting agents such as titanium oxide powder and aluminum oxide powder; anti-caking agent, or conductivity-imparting agents such as carbon black powder, zinc oxide powder and tin oxide powder; It is also possible to use a small amount of reverse polarity organic fine particles and inorganic fine particles as a developing property improver.

A known method is used for producing the toner according to the present invention. For example, a binder resin, a wax, a metal salt or a metal complex, a pigment as a colorant, a dye, or a magnetic material, if necessary. Accordingly, the charge control agent and other additives are sufficiently mixed by a mixer such as a Henschel mixer or a ball mill, and then melt-kneaded by using a heat kneader such as a heating roll, a kneader, or an extruder so that the resins are mixed with each other. By dispersing or dissolving a metal compound, a pigment, a dye, and a magnetic substance in a compatible solution, cooling and solidifying, crushing, performing classification and surface treatment to obtain toner particles, by adding and mixing inorganic fine powder, The toner according to the invention can be obtained. Either the classification or the surface treatment may be performed first. In the classification step, it is preferable to use a multi-division classifier in terms of production efficiency.

Examples of the surface treatment include a hot water bath method in which pulverized toner particles are dispersed in water and heated, a heat treatment method in which a hot air stream is passed through, and a mechanical impact method in which mechanical energy is applied for treatment. In the present invention, the processing temperature in the mechanical impact method is set to the glass transition point Tg of the toner particles.
The thermo-mechanical shock that adds a temperature near (Tg ± 10 ℃)
It is preferable from the viewpoint of aggregation prevention and productivity. More preferably, it is carried out at a temperature in the range of the glass transition point Tg ± 5 ° C. of the toner, in order to reduce the pores having a radius of 10 nm or more on the surface, to effectively work the inorganic fine powder, and to improve the transfer efficiency. It is valid.

Further, the toner according to the present invention is disclosed in Japanese Examined Patent Publication No.
The toner can be produced by a method described in JP-A-13945, etc., in which a molten mixture is atomized in air using a multi-fluid nozzle to obtain spherical toner.

On the other hand, the toner carrying member used in the present invention 1 has a cylindrical substrate such as aluminum and a coating layer for coating the surface of the substrate. FIG. 1 shows the configuration of the toner carrier of the invention 1. In FIG. 1, the toner carrier 1 has a substrate 5 and a coating layer 6. Further, the coating layer 6 is composed of particles 2 for imparting roughness to the surface of the toner carrier, a binder resin 3 and a conductive substance 4.

The coating layer contains at least particles for imparting roughness to the surface of the toner carrier, a conductive substance, and a binder resin. The size of particles for imparting roughness to the surface of the toner carrier used in the present invention is a number average particle diameter of 0.05 to 100 μm, preferably 0.5 to 50 μm.
Particularly, 1.0 to 20 μm is preferable. If the number average particle size of the particles is less than 0.05 μm, the toner carrying ability is lowered, and
If it exceeds 0 μm, the particles tend to be separated from the coating, which is not preferable.

The particle size of the particles for imparting roughness to the surface of the toner carrier according to the present invention is measured by using a laser diffraction type particle size distribution meter, Coulter LS-130 type particle size distribution meter (manufactured by Coulter Co.). Then, the number average diameter obtained from the number distribution was obtained.

Specific examples of particles which are preferably used in the present invention 1 for imparting roughness to the surface of the toner carrier include:
For example, PMMA, acrylic resin, polybutadiene resin,
Polystyrene resin, polyethylene, polypropylene, polybutadiene, or their copolymers, benzoguanamine resin, phenol resin, polyamide resin, nylon,
Resin particles such as fluorine resin, silicone resin, epoxy resin and polyester resin, or inorganic compound particles such as silica, alumina, zinc oxide, titanium oxide, zirconium oxide, calcium carbonate, magnetite, ferrite and glass To be As the particles for imparting roughness to the surface of the toner carrier of the present invention 1, spherical particles having the above-mentioned size or particles having a shape close to a spherical shape are particularly preferably used. It is also possible to use a mixture of inorganic particles and organic particles as particles for imparting roughness to the surface of the toner carrier. Of the organic particles, crosslinked resin particles are suitable and preferred. The addition amount of particles for imparting roughness to the surface of the toner carrier in the coating layer used in the present invention 1 is 2 to 100 parts by mass of the binder resin.
A range of 120 parts by weight gives particularly favorable results. If it is less than 2 parts by mass, the effect of adding spherical particles is small, and if it exceeds 120 parts by mass, the charging property of the toner may be too low.

As the conductive material in the coating layer used in the present invention 1, carbon black such as furnace black, lamp black, thermal black, acetylene black and channel black; titanium oxide, tin oxide, zinc oxide, molybdenum oxide, Examples thereof include metal oxides such as potassium titanate, antimony oxide and indium oxide; metals such as aluminum, copper, silver and nickel; and inorganic fillers such as graphite, metal fibers and carbon fibers. In the present invention, graphite, carbon black or a mixture of graphite and carbon black is particularly preferably used. As the graphite used in the present invention, both a natural product and a synthetic product can be used. It is difficult to unambiguously specify the preferable particle size of graphite due to the fact that the graphite has a scaly shape and that the shape changes during the dispersion step during the production of the toner carrier, but the major axis direction The width (in the direction of the broken surface) is preferably 100 μm or less. As a measuring method, the sample is directly observed with a microscope for measurement. The amount of the conductive substance added to the coating layer used in the present invention is in the range of 10 to 120 parts by mass with respect to 100 parts by mass of the binder resin, and particularly preferable results are obtained. When it exceeds 120 parts by mass, the film strength and the toner charge amount decrease, and when it is less than 10 parts by mass, the toner may be easily contaminated on the surface of the coating layer.

As the binder resin used in the coating layer of the toner carrier of the present invention 1, generally known resins can be used. For example, styrene resin, vinyl resin, polyether sulfone resin, polycarbonate resin, polyphenylene oxide resin, polyamide resin, fluororesin, fibrous resin, acrylic resin, or other thermoplastic resin,
A heat or light curable resin such as an epoxy resin, a polyester resin, an alkyd resin, a phenol resin, a melamine resin, a polyurethane resin, a urea resin, a silicone resin or a polyimide resin can be used. Above all, it has excellent releasability such as silicone resin and fluororesin, or excellent mechanical properties such as polyether sulfone, polycarbonate, polyphenylene oxide, polyamide, phenol, polyester, polyurethane, styrene resin and acrylic resin. More preferred are:

The roughness of the surface of the conductive coating layer of the toner carrier of the present invention 1 is 0.2 as the center line average roughness (hereinafter Ra).
˜4.5 μm, preferably 0.4 to 3.5 μm. If the surface roughness is less than 0.2 μm, the toner transportability may be deteriorated, and sufficient image density may not be obtained.
If it exceeds 4.5 μm, the toner conveyance amount becomes too large, and the chargeability of the toner becomes insufficient. The film thickness of the conductive coating layer is usually preferably 20 μm or less in order to obtain a uniform film thickness, but it is not particularly limited to this film thickness.

The center line average roughness (Ra) is defined by JIS
Based on the surface roughness (B0601), a surf coder SE-3300 manufactured by Kosaka Laboratory was used to measure 3 points in the axial direction × 2 points in the circumferential direction = 6 points, and the average value was used.

The surface roughness of the toner carrier used in the present invention 2 is 0.2 to JIS standard line average roughness (Ra).
It is preferably in the range of 3.5 μm.

If Ra is less than 0.2 μm, the amount of charge on the toner carrier becomes high and the developability becomes insufficient. When Ra exceeds 3.5 μm, unevenness occurs in the toner coat layer on the toner carrier, resulting in uneven density on the image. More preferably, it is in the range of 0.5 to 3.0 μm.

Further, since the magnetic toner of the present invention 2 has a high charging ability, it is desirable to control the total charge amount of the toner during development. The surface of the toner carrier according to the present invention 2 has conductive fine particles and / or Alternatively, it is preferably covered with a resin layer in which a lubricant is dispersed.

As the conductive fine particles contained in the resin layer coating the surface of the toner carrier, conductive metal oxides such as carbon black, graphite and conductive zinc oxide, and metal complex oxides may be used alone or in combination of two or more. It is preferably used. Further, as the resin in which the conductive fine particles are dispersed, a phenol resin, an epoxy resin, a polyamide resin, a polyester resin, a polycarbonate resin,
Known resins such as polyolefin resins, silicone resins, fluorine resins, styrene resins, and acrylic resins are used.

A thermosetting or photocurable resin is particularly preferable.

When the one-component developing method is used in the present invention 2, a layer smaller than the closest distance (between S and D) between the toner carrier and the latent image carrier is provided on the toner carrier in order to obtain high image quality. It is preferable that the toner is developed in a thick developing process in which a magnetic toner is applied and an alternating electric field is applied to develop.

The present invention is effective when the surface of the image bearing member is mainly composed of a polymer binder. For example, when a protective film mainly composed of a resin is provided on an inorganic image bearing member such as selenium or amorphous silicon, or as a charge transporting layer of a function separation type organic image bearing member, a surface layer comprising a charge transporting material and a resin. In some cases, the above-mentioned protective layer may be further provided on it. As a means for imparting releasability to such a surface layer, a resin having a low surface energy is used for the resin constituting the film, an additive for imparting water repellency and lipophilicity is added, and high releasability is provided. And a method of dispersing the material having
For example, it is achieved by introducing a fluorine-containing group, a silicon-containing group or the like into the resin structure. as,
A surfactant or the like may be used as the additive. Is a compound containing a fluorine atom, that is, polytetrafluoroethylene,
Examples of the powder include polyvinylidene fluoride and carbon fluoride. Among these, polytetrafluoroethylene is particularly preferable. In the present invention, it is particularly preferable to disperse the releasable powder such as the fluorine-containing resin in the outermost surface layer.

By these means, the contact angle of water on the surface of the image bearing member can be 85 degrees or more (preferably 90 degrees or more). If it is less than 85 degrees, deterioration of the toner and the toner carrier due to durability tends to occur.

In order to contain these powders on the surface, a layer in which the powders are dispersed in a binder resin is provided on the outermost surface of the image bearing member, or an organic material mainly composed of resin is used. In the case of an image carrier, the powder may be dispersed in the uppermost layer without providing a new surface layer.

The amount of the powder added to the surface layer is preferably 1 to 60% by mass, more preferably 2 to 50% by mass, based on the total mass of the surface layer. If it is less than 1% by mass, the effect of improving the durability of the toner and the toner carrier is insufficient, and 60% by mass
If it exceeds, the strength of the film is lowered, or the amount of light incident on the image carrier is significantly lowered, which is not preferable.

The present invention is particularly effective when the charging means is the direct charging method in which the charging member is brought into contact with the image carrier. Compared to corona discharge or the like in which the charging means does not come into contact with the image carrier, the load on the surface of the image carrier is large, so that the effect of improving the life of the image carrier is remarkable, which is one of the preferable application modes.

One of the preferred embodiments of the image carrier used in the present invention will be described below.

Examples of the conductive substrate include metals such as aluminum and stainless steel, aluminum alloys, and indium oxide.
Cylindrical cylinders and films of plastic having a coating layer of tin oxide alloy, paper impregnated with conductive particles, plastic, plastic having conductive polymer, and the like are used.

On these conductive substrates, the adhesiveness of the photosensitive layer is improved, the coatability is improved, the substrate is protected, and the defects on the substrate are covered.
An undercoat layer may be provided for the purpose of improving the charge injection property from the substrate and protecting the photosensitive layer against electrical breakdown. The subbing layer is polyvinyl alcohol, poly-N-vinyl imidazole, polyethylene oxide, ethyl cellulose, methyl cellulose, nitrocellulose, ethylene-acrylic acid copolymer, polyvinyl butyral, phenol resin, casein, polyamide, copolymer nylon, glue,
It is formed of a material such as gelatin, polyurethane, aluminum oxide or the like. The film thickness is usually 0.1 to 10 μm,
It is preferably about 0.1 to 3 μm.

The charge generation layer comprises azo pigments, phthalocyanine pigments, indigo pigments, perylene pigments, polycyclic quinone pigments, squarylium dyes, pyrylium salts, thiopyrylium salts, triphenylmethane dyes, selenium,
It is formed by dispersing a charge generating substance such as an inorganic substance such as amorphous silicon in a suitable binder and coating or vapor depositing. The binder can be selected from a wide range of binder resins, for example, polycarbonate resin, polyester resin, polyvinyl butyral resin, polystyrene resin, acrylic resin, methacrylic resin, phenol resin, silicone resin, epoxy resin, vinyl acetate resin, etc. Is mentioned. The amount of the binder contained in the charge generation layer is 80% by mass.
Below, it is preferably selected to be 0 to 40% by mass. The film thickness of the charge generation layer is preferably 5 μm or less, and particularly preferably 0.05 to 2 μm.

The charge transport layer has a function of receiving charge carriers from the charge generation layer in the presence of an electric field and transporting them. The charge transport layer is formed by dissolving a charge transport substance in a solvent, if necessary, together with a binder resin, and coating the solution, and the film thickness thereof is generally 5 to 40 μm. As the charge transport substance, biphenylene is added to the main chain or side chain,
Polycyclic aromatic compounds having a structure such as anthracene, pyrene and phenanthrene, nitrogen-containing cyclic compounds such as indole, carbazole, oxadiazole and pyrazoline,
Hydrazone compounds, styryl compounds, selenium, selenium-
Tellurium, amorphous silicon, cadmium sulfide, etc. may be mentioned.

As the binder resin in which these charge transporting substances are dispersed, polycarbonate resin, polyester resin, polymethacrylate ester, polystyrene resin,
Examples thereof include resins such as acrylic resins and polyamide resins, organic photoconductive polymers such as poly-N-vinylcarbazole, and polyvinylanthracene.

A protective layer may be provided as the surface layer. As the resin for the protective layer, polyester, polycarbonate, acrylic resin, epoxy resin, phenol resin, or a curing agent of these resins may be used alone or in combination.
Used in combination of more than one species.

Further, conductive fine particles may be dispersed in the resin of the protective layer. Examples of the conductive fine particles include metals and metal oxides, and preferably zinc oxide, titanium oxide, tin oxide, antimony oxide, indium oxide, bismuth oxide, tin oxide coated titanium oxide, tin coated indium oxide, Antimony coating There are ultrafine particles such as tin oxide and zirconium oxide. These may be used alone or in combination of two or more. Generally, when the particles are dispersed in the protective layer, it is necessary that the particle size of the particles is smaller than the wavelength of the incident light in order to prevent scattering of the incident light by the dispersed particles, and the particles are dispersed in the protective layer in the present invention. The particle diameter of the conductive and insulating particles is preferably 0.5 μm or less. The content in the protective layer is preferably 2 to 90% by mass, more preferably 5 to 80% by mass, based on the total mass of the protective layer. The thickness of the protective layer is preferably 0.1 to 10 μm, more preferably 1 to 7 μm.

The surface layer can be applied by spray coating, beam coating or dipping coating of the resin dispersion.

Next, a preferred embodiment of the image forming method of the present invention will be specifically described with reference to the drawings.

In FIG. 2, reference numeral 100 is an electrostatic latent image carrier (photoconductor) around which a primary charging member 117, a developing device 140, a transfer means 114, a cleaner 116, a resist roller 124 and the like are provided. Electrostatic latent image carrier 10
A bias is applied to the primary charging member 117 which is in contact with 0, and the electrostatic latent image carrier 100 is uniformly primary-charged. Then, the laser light 123 is generated by the laser generator 121.
An electrostatic latent image is formed by irradiating and exposing the latent image carrier 100 with. As shown in FIG. 3, the developing device 140 is in the vicinity of the latent image carrier 100, and a toner carrier (developing sleeve) 102 having a coating layer provided on a cylindrical substrate made of non-magnetic metal such as aluminum or stainless steel. Is provided, and the gap between the latent image carrier 100 and the toner carrier 102 is maintained constant by a toner carrier / latent image carrier gap holding member (not shown). In addition, a stirring bar 14 is provided in the developing unit.
1, a magnet roller 104 having a plurality of magnetic poles is fixed and arranged concentrically with the toner carrier 102 in the developing sleeve, and the toner carrier 102 is rotatable. The magnet roller 104 is provided with a plurality of magnetic poles as shown in the drawing. S ₁ influences development, N ₁ influences toner amount regulation, S ₂ influences toner intake / conveyance, and N ₂ influences toner blowout prevention. . A contact blade 103 is provided as a member that regulates the amount of magnetic toner attached to and carried by the toner carrier 102, and controls the amount of toner carried by the toner carrier 102. In the developing area, a developing bias is applied between the latent image carrier 100 and the toner carrier 102, and the toner on the toner carrier flies onto the latent image carrier 100 according to the electrostatic latent image to form a visible image. Become. Latent image carrier 1
The upper toner image 00 is transferred onto the transfer material by the transfer means 114 to which a DC voltage having a polarity opposite to that of the toner is applied. The transfer material on which the toner image is placed is conveyed to the fixing device 126 by the conveyor belt 125 or the like and fixed on the transfer material. In addition, the toner partially left on the latent image carrier is cleaned by the cleaning unit 116.

As a transfer means in the contact transfer step, a device having a transfer roller 114 as shown in FIG. 8 or a transfer belt 120 as shown in FIG. 9 is used. The transfer roller 114 includes at least a core metal 114a and a conductive elastic layer 114b, and the conductive elastic layer 114b is an elastic body such as urethane or EPDM in which a conductive material such as carbon is dispersed and having a volume resistance of about 10 ⁶ to 10 ¹⁰ Ωcm. Is made of.

The toner layer thickness on the toner carrier of the present invention is set smaller than the closest gap between the image carrier and the toner carrier by the toner layer thickness regulating member, and the toner layer thickness regulating member is the toner layer thickness regulating member. It is particularly preferable from the viewpoint of uniformly charging the toner that the toner is regulated by the elastic member that is in contact with the toner carrier via the.

Further, in the present invention, it is preferable from the viewpoint of environmental protection that the charging member is in contact with the photosensitive member so that ozone is not generated.

A preferable process condition when a charging roller is used is that the contact pressure of the roller is 5 to 500 g /
cm, when using a DC voltage superposed with an AC voltage, AC voltage = 0.5 to 5 kVpp, AC frequency =
50 Hz to 5 kHz, DC voltage = ± 0.2 to ± 5 kV.

As another charging means, there are a method using a charging blade and a method using a conductive brush. These contact charging means have an effect that a high voltage is unnecessary and ozone generation is reduced.

As the material of the charging roller and the charging blade as the contact charging means, conductive rubber is preferable, and a releasing film may be provided on the surface thereof. As the releasable coating, nylon resin, PVdF (polyvinylidene fluoride), PVdC (polyvinylidene chloride), fluoroacrylic resin, etc. can be applied.

[0114]

EXAMPLES The present invention will be specifically described below with reference to production examples and examples, but the present invention is not limited thereto. In the following formulation, all parts are parts by mass.

First, an example according to the present invention 1 will be described.

[0116]   (Toner Production Example 1)   ・ Magnetic material (average particle size 0.22 μm) 100 parts   ・ Styrene-butyl acrylate-butyl maleate half ester copolymer     (Mw = 300000, Mn = 10000, glass transition point Tg = 61 ° C.)                                                               100 copies   ・ Monoazo dye iron complex (negative charge control agent) 2 parts   ・ Low molecular weight polyolefin (release agent) 3 parts

The above materials were mixed in a blender,
Melted and kneaded with a twin-screw extruder heated to ℃, cooled and crushed the kneaded material roughly with a hammer mill, finely crushed the coarsely crushed material with a jet mill, and the resulting finely crushed material is multi-divided using the Coanda effect. Strict classification was carried out with a classifier to obtain magnetic toner particles. The magnetic toner particles are subjected to a surface treatment with a thermo-mechanical impact force (treatment temperature 60 ° C.), and the obtained magnetic toner particles are hydrophobized with silicone oil and hexamethyldisilazane. (BET specific surface area after treatment 120 m ² / g) was added in an amount of 1.6% by mass and mixed by a mixer to obtain a magnetic toner A1.

The obtained magnetic toner A1 has a weight average particle diameter of 6.5 μm, a number average particle diameter of 5.5 μm and SF-1 is 1.
44, SF-2 is 124, BET specific surface area is 2.8 m ^2.
/ G. The BET specific surface area of the toner particles was 1.0 m ² / g. Table 1 shows the physical properties of the obtained magnetic toner.

The dry silica added was hydrophobized with hexamethyldisilazane to give a dry silica having a primary particle diameter of 12 nm (BET specific surface area after the treatment of 160 m ² / g).
The magnetic toner A2 was changed to 1.4% by mass, and the dry silica having a primary particle diameter of 12 nm which was not subjected to the hydrophobic treatment (BET after the treatment was used.
The magnetic toner A3 were respectively obtained by changing the specific surface area 300m ² /g)0.9 wt%. Table 1 shows the physical properties of the obtained magnetic toner.

[0120]   (Toner Production Example 2)   ・ Magnetic material (average particle size 0.22 μm) 100 parts   ・ Styrene-butyl acrylate-butyl maleate half ester copolymer     (Peak molecular weight = about 10,000, Mw = 200,000, Mn = 5000,       Glass transition point Tg = 62 ° C) 100 parts   ・ Monoazo dye iron complex (negative charge control agent) 2 parts   ・ Low molecular weight polyolefin (release agent) 3 parts

By using the above-mentioned materials, the treatment temperature of the toner particles by thermo-mechanical impact is set to 59 ° C., and the primary particle diameter of the inorganic fine powder 18 made hydrophobic with silicone oil 18
nm dry alumina (BET specific surface area after treatment 100 m
Magnetic toner B1 having a weight average particle diameter of 7.0 μm was obtained in the same manner as in Toner Production Example 1 except that 1.8% by weight of ² / g) was used. Table 1 shows the physical properties of the obtained magnetic toner.

Further, dry silica having a primary particle size of 12 nm which has been hydrophobized with silicone oil and hexamethyldisilazane as an inorganic fine powder (BET specific surface area after treatment 120
m ^{2 /} g) 1.6% by mass and spherical silica (BET after treatment)
Specific surface area of 5 m ² / g, primary particle size of 1.0 μm) Magnetic toner B2 was changed to 0.3% by mass, and magnetic toner B2 was hydrophobized with silicone oil and hexamethyldisilazane.
m dry silica (BET specific surface area after treatment 120 m ² /
g) 1.6% by mass and spherical resin particles (primary particle size 0.4 μ
m) The magnetic toner B3 was changed to 0.2% by mass, and the dry silica having a primary particle diameter of 12 nm which had been hydrophobized with silicone oil and hexamethyldisilazane (BET specific surface area after treatment 120 m ^{2 /} g) was 1.6. Amorphous resin particles (primary particle size 0.8 μm) of mass% are changed to 0.2 mass% and magnetic toner B is used.
Got 4. Table 1 shows the physical properties of the obtained magnetic toner.

[0123]   (Toner Production Example 3)   ・ Magnetic material (average particle size 0.24 μm) 90 parts   ・ Polyester resin     (Mw = 400,000, Mn = 6000, glass transition point Tg = 58 ° C.)                                                               100 copies   ・ Chromium complex of monoazo dye (negative charge control agent) 2 parts   ・ Low molecular weight polyolefin (release agent) 3 parts

A weight average particle diameter of 8.2 μm was obtained in the same manner as in Toner Production Example 1 except that the above materials were used and the treatment temperature of the toner particles by thermo-mechanical impact was 65 ° C.
Magnetic toner C of No. Table 1 shows the physical properties of the obtained magnetic toner.

(Toner Production Example 4) In Toner Production Example 1, the treatment temperature of the toner particles by thermo-mechanical impact was 51 ° C.
And 1.8% by mass of titanium oxide fine particles having a primary particle size of 20 nm (BET specific surface area after treatment 100 m ² / g) hydrophobized with silicone oil as an inorganic fine powder.
A magnetic toner D having a weight average particle diameter of 6.5 μm was obtained in the same manner as in Toner Production Example 1 except that it was used. Table 1 shows the physical properties of the obtained magnetic toner.

(Toner Production Example 5) In toner production example 1, the surface treatment by thermo-mechanical impact was not performed,
Inorganic fine powder was hydrophobized with silicone oil and hexamethyldisilazane. Dry silica with a primary particle diameter of 70 nm (BET specific surface area after treatment 30 m ² / g) was changed to 3.0% by mass in the same manner except that the content was changed to 3.0% by mass. Toner E was obtained. Table 1 shows the physical properties of the obtained magnetic toner.

[0127]   (Toner Production Example 6)   ・ Magnetic material (average particle size 0.24 μm) 60 parts   ・ Styrene-butyl acrylate-butyl maleate half ester copolymer     (Low molecular weight peak = about 15,000, Mw = 250,000, Mn = 7000,       Glass transition point Tg = 63 ° C) 100 parts   ・ Chromium complex of monoazo dye (negative charge control agent) 2 parts   ・ Low molecular weight polyolefin (release agent) 2 parts

A magnetic toner F having a weight average particle diameter of 10.5 μm was obtained in the same manner as in Toner Production Example 1 except that the above materials were used and the treatment of the toner particles by thermo-mechanical impact was not performed. Table 1 shows the physical properties of the obtained magnetic toner.

[0129]

[Table 1]

[0130]   [Development sleeve manufacturing example 1] Resol-type phenol resin solution (containing 50% methanol) 200 parts Graphite (number average particle size 9 μm) 50 parts Conductive carbon black 5 parts Isopropyl alcohol 130 parts

Zirconia beads having a diameter of 1 mm were added as media particles to the above material, dispersed in a sand mill for 2 hours, and the beads were separated using a sieve to obtain a stock solution. Next, spherical PMMA particles (number average particle size 1
2 μm) and 10 parts of isopropyl alcohol so that the solid content concentration is 30%, and then the diameter is 3 mm.
The glass beads of 1 were dispersed for 1 hour, and the beads were separated using a sieve to obtain a coating liquid.

Using this coating solution, a coating layer is formed on an aluminum cylindrical tube having an outer diameter of 16 mmφ by a spray method, followed by heating in a hot air drying oven at 150 ° C. for 30 minutes to cure the developing sleeve 1. did. Development sleeve 1
Ra value of Ra was 1.9 μm.

[Development Sleeve Production Example 2] Development sleeve production example 1 is the same as development sleeve production example 1 except that the spherical particles are 10 parts of spherical nylon resin particles (number average particle size 9 μm). Got 2. The Ra value of the obtained developing sleeve 2 was Ra = 2.2 μm.

[Development Sleeve Comparative Production Example 1] The aluminum cylindrical tube used in Development Sleeve Production Example 1 was subjected to only sandblasting to obtain a development sleeve 3. The Ra value of the developing sleeve 3 thus obtained was Ra = 1.9 μm.

<Photoreceptor Production Example 1> As a photoreceptor, the diameter is 3
The base was a 0 mm Al cylinder. A layer having a structure as shown in FIG. 4 was sequentially laminated thereon by dip coating to prepare a photoconductor 1.

(1) Conductive coating layer: Mainly composed of tin oxide and titanium oxide powder dispersed in a phenol resin. Film thickness 15 μm.

(2) Undercoat layer: Mainly composed of modified nylon and copolymer nylon. The film thickness is 0.6 μm.

(3) Charge generating layer: Mainly composed of an azo pigment having absorption in the long wavelength region dispersed in butyral resin. The film thickness is 0.6 μm.

(4) Charge transport layer: Mainly composed of a hole-transporting triphenylamine compound dissolved in a polycarbonate resin (molecular weight of 20,000 by Oswald viscosity method) at a weight ratio of 8:10, and further polytetrafluoroethylene. 10% by mass of powder (particle size: 0.2 μm) was added to the total solid content and uniformly dispersed. The film thickness is 25 μm. The contact angle with water was 95 degrees.

Pure water was used to measure the contact angle, and a contact angle meter CA-X type manufactured by Kyowa Interface Science Co., Ltd. was used as the apparatus.

<Photoreceptor Production Example 2> Photoreceptor 2 was produced in the same manner as in Photoreceptor Production Example 1 without adding polytetrafluoroethylene powder. The contact angle with water was 74 degrees.

Example 1 An image forming apparatus shown in FIG. 2 was used as the image forming apparatus.

Production Example 1 of developing sleeve as toner carrier
In the developing device using the developing sleeve 1 of No. 1, the magnetic toner A1 of Toner Production Example 1 is used, and the organic photoconductor (OPC) drum of Photoconductor Production Example 1 is used as the electrostatic latent image carrier, and the dark potential V _d =- It was set to 600V and the light portion potential _VL = -150V.
The gap between the photosensitive drum and the developing sleeve was 300 μm.

DC bias component V _{dc is used} as the developing bias.
= -400V, superimposed AC bias component _VPP = 12
00V, f = 2000Hz was used. The peripheral speed of the developing sleeve was 120% (108 mm / sec) in the forward direction with respect to the peripheral speed of the photoconductor (90 mm / sec).

Further, a transfer roller 114 as shown in FIG. 2 (made of ethylene-propylene rubber in which conductive carbon is dispersed, volume resistance value of conductive elastic layer 10 ⁸ Ωcm, surface rubber hardness 24 °, diameter 20 mm, contact) Pressure 49 N / m (50 g
/ Cm) is constant with respect to the peripheral speed of the photoconductor (90 mm / sec), and +2000 V is applied as a transfer bias, and 2
Images were printed on 5,000 sheets in an environment of 3 ° C. and 65% RH, and the transferability was evaluated at the initial stage and after 5,000 sheets. As the transfer paper, 75 g / m ² paper was used.

At this time, the transfer efficiency from the photosensitive member to the transfer material was 97% at the initial stage and 96% after 5,000 sheets.
It showed a high transfer efficiency without deterioration due to durability, no voids in the transfer of characters or lines, and a good image with high density and no fog.

In the present invention, the transferability is as follows. The transfer residual toner on the solid black photosensitive member is taped off with Mylar tape and peeled off. The value was evaluated by subtracting the concentration.

Further, when the surface of the developing sleeve was observed continuously and images were printed up to 10,000 sheets, neither contamination nor toner fusion was observed. Further, when the abrasion amount of the photoconductor was measured by a film thickness meter, the abrasion amount was very small, less than 1 μm.

The above results are summarized in Table 2.

Example 2 Image formation was performed under the same apparatus and conditions as in Example 1 except that Toner A2 was used as the toner, and good results as shown in Table 2 were obtained.

Example 3 Toner Image formation was performed under the same apparatus and conditions as in Example 1 except that Toner A3 of Production Example 1 was used. As shown in Table 2, as compared with Example 1, a slight transfer occurred. The properties and densities were low, and lines and blank characters were slightly bad, but sufficient performance with no problem in practical use was obtained.

Example 4 Toner Image formation was carried out under the same apparatus and conditions as in Example 1 except that Toner D of Production Example 4 was used. Although the performance is low and the image density is slightly low, sufficient performance with no problem in practical use was obtained.

Comparative Example 1 Toner Image formation was performed under the same apparatus and conditions as in Example 1 except that Toner E of Production Example 5 was used, but when 5000 sheets were printed, the density was slightly reduced and the character lines were missing during transfer. A good image was obtained except that the above was observed, but the transfer efficiency from the photoconductor to the transfer material was 89% at the initial stage and 79% after 5,000 sheets, and sufficient performance was obtained as compared with Examples 1 to 4. There wasn't.

Comparative Example 2 Image formation was carried out under the same apparatus and conditions as in Example 1 except that Toner E and developing sleeve 3 were used. As a result, the ghost was conspicuous in the initial image, and the toner fusion to the sleeve occurred further after 1000 sheets, and the image density was significantly lowered, so the evaluation was stopped. The transfer efficiency from the photoconductor to the transfer material was 85% at the initial stage.

Examples 5 to 8 Developing sleeve: Image development is performed under the same apparatus and conditions as in Example 1 except that the developing sleeve 2 of Manufacturing Example 2 and the toners B3, B2, B1 and B4 of Toner Manufacturing Example 2 are used. I went. As a result, as shown in Table 2, in Examples 5 to 7, transfer efficiency was good, and good images were obtained without omission of transfer of characters and lines. In Example 8, the transfer efficiency after 5000 sheets was slightly low,
In addition, the image density was also slightly low, and there were some voids in the transfer of characters and lines, but practically sufficient results were obtained.

Example 9 Image formation was carried out under the same apparatus and conditions as in Example 1 except that Toner C and Photoreceptor 2 were used. As shown in Table 2, good results with no practical problems were obtained. Was obtained.

Comparative Example 3 Images were printed under the same apparatus and conditions as in Example 1 except that Toner F was used. As a result, some voids in the transfer of characters and lines were observed from the initial stage, and further after 5000 sheets, further printing was performed. It became remarkable. The transfer efficiency from the photoconductor to the transfer material is 84 at the initial stage.
%, It was 78% after 5000 sheets, and sufficient performance was not obtained as compared with the examples.

[0158]

[Table 2]

<Evaluation criteria> Transfer efficiency ◎: 95% or more ○: 95 to 90% ○ △; 89-85% △; 84-80% ×: less than 80%

Solid black density ◎: 1.45 or more ○; ~ 1.40 ○ △; ~ 1.35 △; ~ 1.30 ×: less than 1.30

Missing line / character ◎: Not at all ○: almost no ○ △; Slightly but not noticeable △: Slightly noticeable but practically no problem ×: Very conspicuous

Staining of sleeve etc. ◎: None at all ○: Slight contamination or fusion on the sleeve, but not at all on the image ○ △; Contamination or fusion on the sleeve, but little effect on the image △; There is contamination or fusion on the sleeve and the image has an acceptable level of impact on practical use. X: Contamination or fusion on the sleeve is significant and the image is significantly affected, making it impractical.

Next, an embodiment according to the present invention 2 will be described.

[0164]   (Toner Production Example 7)   ・ Magnetic material (average particle size 0.22 μm) 100 parts   ・ Styrene-butyl acrylate-butyl maleate half ester copolymer     (Mn = 0.78 million, Mw = 350,000, molecular weight 2000 or less = 6%,       Molecular weight 1 million or more = 12%, glass transition point Tg = 67 ° C) 100 parts   ・ Monoazo dye iron complex (negative charge control agent) 2 parts   ・ Low molecular weight polyolefin (release agent) 4 parts

The above materials were mixed in a blender to obtain 130
Melted and kneaded with a twin-screw extruder heated to ℃, cooled and crushed the kneaded material roughly with a hammer mill, finely crushed the coarsely crushed material with a jet mill, and the resulting finely crushed material is multi-divided using the Coanda effect. Strictly classifying with a classifier gave a classified fine powder. With respect to the fine powder, dry silica having a primary particle diameter of 12 nm which has been subjected to a hydrophobic treatment with silicone oil and hexamethyldisilazane as an inorganic fine powder for surface fixation (BET after treatment)
1.0 mass% of a specific surface area of 120 m ² / g) was added and mixed by a mixer. Then, the mixture was surface-treated by thermo-mechanical impact force (treatment temperature 65 ° C.) to obtain magnetic toner particles. By electron microscope observation and BET measurement of toner particles,
It was confirmed that the silica was fixed on the surface.

Then, with respect to the obtained magnetic toner particles,
Dry silica with a primary particle size of 12 nm that has been hydrophobized with silicone oil and hexamethyldisilazane (BE after treatment)
0.8% by mass of T specific surface area 120 m ² / g) was added and mixed by a mixer, and then coarse particles were removed through a 100 mesh sieve to obtain a magnetic toner 1. The obtained magnetic toner 1 has a weight average particle diameter of 6.9 μm, SF-1 is 145, and SF-2 is 12
It was 6. Table 3 shows the physical properties of the obtained magnetic toner 1.

(Toner Production Example 8) In Toner Production Example 7, classified fine powder was prepared by changing the pulverization and classification conditions, and the primary particle diameter of the surface-immobilized inorganic fine powder was hydrophobized with silicone oil and hexamethyldisilazane. 12 nm of dry silica (BET specific surface area after treatment of 120 m ² / g) was 2.
Surface treatment was performed using 0 mass% to obtain magnetic toner particles. 0.5% by mass of dry silica having a primary particle diameter of 12 nm and subjected to hydrophobic treatment with hexamethyldisilazane (BET specific surface area after treatment, 160 m ² / g) was added to the obtained magnetic toner particles.
After adding and mixing with a mixer, coarse particles were removed with a 100-mesh sieve to obtain a magnetic toner 2. Magnetic toner 2 obtained
The physical properties of are shown in Table 3.

(Toner Production Example 9) In Toner Production Example 7, classified fine powders were prepared by changing the pulverizing and classification conditions, and the primary particle diameter of the surface-fixed inorganic fine powders was hydrophobized with silicone oil and hexamethyldisilazane. 12 nm of dry silica (BET specific surface area after treatment 120 m ² / g) was adjusted to 0.
Surface treatment was performed using 3% by mass to obtain magnetic toner particles. The obtained magnetic toner particles were hydrophobized with silicone oil and hexamethyldisilazane to have a primary particle size of 8 nm.
Dry silica (BET specific surface area after treatment 100 m ² /
g) 1.5% by mass, spherical silica having a primary particle size of 1 μm (B
0.5 mass% of ET specific surface area of 5 m ² / g) was added and mixed by a mixer, and then coarse particles were removed by a 100 mesh sieve to obtain a magnetic toner 3. Table 3 shows the physical properties of the obtained magnetic toner 3.
Shown in.

[0169]   (Toner Production Example 10)   ・ Magnetic material (average particle size 0.18 μm) 90 parts   ・ Styrene-butyl acrylate-butyl maleate half ester copolymer     (Mn = 0.510,000, Mw = 150,000, molecular weight 2000 or less = 8%,       Molecular weight 1 million or more = 4%, glass transition point Tg = 61 ° C) 100 parts   ・ Monoazo dye iron complex (negative charge control agent) 2 parts   ・ Low molecular weight polyolefin (release agent) 4 parts

Using the above materials, classified fine powder was obtained in the same manner as in Toner Production Example 7. 1.0% by mass of dry silica (BET specific surface area after treatment, 160 m ² / g) having a primary particle size of 12 nm, which had been hydrophobized with hexamethyldisilazane, was added to the fine powder as an inorganic fine powder for surface fixation. , And mixed with a mixer. Then, the mixture was surface-treated by thermo-mechanical impact force (treatment temperature 65 ° C.) to obtain magnetic toner particles. Dry magnetic silica having a primary particle size of 8 nm, which was hydrophobized with silicone oil and hexamethyldisilazane, was added to the obtained magnetic toner particles (BET specific surface area after treatment 100 m ² / g)
Of 0.8% by mass and 0.2% by mass of PMMA particles having a primary particle size of 0.4 μm (BET specific surface area of 13 m ² / g) were mixed with a mixer and coarse particles were removed with a 100 mesh sieve. Magnetic toner 4 was obtained. Table 3 shows the physical properties of the obtained magnetic toner 4.

[0171]   (Toner Production Example 11)   ・ Magnetic material (average particle size 0.22 μm) 100 parts   ・ Styrene-butyl acrylate-butyl maleate half ester copolymer     (Mn = 0.78 million, Mw = 350,000, molecular weight 2000 or less = 6%,       Molecular weight 1 million or more = 12%, glass transition point Tg = 67 ° C) 100 parts   ・ Monoazo dye iron complex (negative charge control agent) 2 parts   ・ Low molecular weight polyolefin (release agent) 5 parts

Using the above materials, classified fine powder was obtained in the same manner as in Toner Production Example 7. 0.8 mass of dry silica (BET specific surface area after treatment, 120 m ² / g) having a primary particle size of 12 nm, which was hydrophobized with silicone oil and hexamethyldisilazane as an inorganic fine powder for surface fixation, was added to the fine powder. %
Add and mix with a mixer. Then, the mixture was surface-treated by thermo-mechanical impact force (treatment temperature 65 ° C.) to obtain magnetic toner particles. To the obtained magnetic toner particles, 1.0% by mass of dry silica (BET specific surface area after treatment, 100 m ² / g) having a primary particle diameter of 8 nm which was hydrophobized with silicone oil and hexamethyldisilazane was added, After mixing with a mixer, coarse particles were removed with a 100-mesh sieve to obtain a magnetic toner 5. Table 3 shows the physical properties of the obtained magnetic toner 5.

[0173]   (Toner Production Example 12)   ・ Magnetic material (average particle size 0.22 μm) 100 parts   ・ Styrene-butyl acrylate-butyl maleate half ester copolymer     (Mn = 0.66 million, Mw = 500,000, molecular weight 2000 or less = 5%,       Molecular weight 1 million or more = 15%, glass transition point Tg = 63 ° C) 100 parts   ・ Monoazo dye iron complex (negative charge control agent) 4 parts   ・ Low molecular weight polyolefin (release agent) 4 parts

Using the above materials, a classified fine powder was obtained in the same manner as in Toner Production Example 7. 0.8 mass of dry silica having a primary particle diameter of 8 nm (BET specific surface area after treatment, 100 m ² / g), which was hydrophobized with silicone oil and hexamethyldisilazane as an inorganic fine powder for surface fixation, was added to the fine powder. %, And mixed with a mixer. Then, the mixture was surface-treated by thermo-mechanical impact force (treatment temperature 65 ° C.) to obtain magnetic toner particles. Dry magnetic silica having a primary particle size of 12 nm, which has been hydrophobized with hexamethyldisilazane (BET specific surface area after treatment, 120 m ² / g)
Was added in an amount of 1.0% by mass and mixed with a mixer, and then coarse particles were removed through a 100-mesh sieve to obtain a magnetic toner 6. Table 3 shows the physical properties of the obtained magnetic toner 6.

[0175]   (Toner Production Example 13)   ・ Magnetic material (average particle size 0.22 μm) 100 parts   ・ Styrene-butyl acrylate-butyl maleate half ester copolymer     (Mn = 0.66 million, Mw = 500,000, molecular weight 2000 or less = 5%,       Molecular weight 1 million or more = 15%, glass transition point Tg = 63 ° C) 100 parts   ・ Monoazo dye iron complex (negative charge control agent) 4 parts   ・ Low molecular weight polyolefin (release agent) 4 parts

Using the above materials, classified fine powder was obtained in the same manner as in Toner Production Example 7. 0.8% by mass of dry silica (BET specific surface area after treatment, 160 m ² / g) having a primary particle size of 12 nm, which was hydrophobized with hexamethyldisilazane, was added to the fine powder as an inorganic fine powder for surface fixation. , And mixed with a mixer. Then, the mixture was surface-treated by thermo-mechanical impact force (treatment temperature 65 ° C.) to obtain magnetic toner particles. To the obtained magnetic toner particles, 1.0% by mass of dry silica having a primary particle size of 16 nm which had been hydrophobized with hexamethyldisilazane (BET specific surface area after treatment 100 m ² / g) was added and added to a mixer. After mixing, coarse particles were removed through a 100-mesh sieve to obtain a magnetic toner 7. Table 3 shows the physical properties of the obtained magnetic toner 7.

[0177]   (Toner Production Example 14)   ・ Magnetic material (average particle size 0.22 μm) 90 parts   ・ Styrene-butyl acrylate-butyl maleate half ester copolymer     (Mn = 0.66 million, Mw = 500,000, molecular weight 2000 or less = 5%,       Molecular weight 1 million or more = 15%, glass transition point Tg = 63 ° C) 100 parts   ・ Monoazo dye iron complex (negative charge control agent) 2 parts   ・ Low molecular weight polyolefin (release agent) 6 parts

Using the above materials, a finely divided powder was obtained in the same manner as in Toner Production Example 7. 1.0 μm of titanium oxide having a primary particle size of 20 nm (BET specific surface area after treatment 100 m ² / g), which was hydrophobized with silicone oil and isobutyltrimethoxysilane, was used as the surface adhering inorganic fine powder.
Mass% was added and mixed by a mixer. Then, the mixture was surface-treated by thermo-mechanical impact force (treatment temperature 65 ° C.) to obtain magnetic toner particles. For the obtained magnetic toner particles,
Primary particle size 1 hydrophobized with hexamethyldisilazane
2 nm dry silica (BET specific surface area after treatment 120 m
² / g) was added in an amount of 1.0% by mass, mixed with a mixer, and then coarse particles were removed through a 100-mesh sieve to obtain a magnetic toner 8. Table 3 shows the physical properties of the obtained magnetic toner 8.

[0179]   (Toner Comparative Production Example 1)   ・ Magnetic material (average particle size 0.22 μm) 60 parts   ・ Styrene-butyl acrylate-butyl maleate half ester copolymer     (Mn = 80,000, Mw = 150,000, molecular weight 2000 or less = 5%,       Molecular weight 1 million or more = 25%, glass transition point Tg = 58 ° C) 100 parts   ・ Monoazo dye iron complex (negative charge control agent) 2 parts   ・ Low molecular weight polyolefin (release agent) 4 parts

Using the above materials, magnetic toner fine powder was obtained in the same manner as in Toner Production Example 7. With respect to the magnetic toner fine powder,
Primary particle size 1 hydrophobized with dimethyldichlorosilane
6 nm dry silica (BET specific surface area 100 m after treatment)
² / g) was added in an amount of 1.0% by mass and mixed with a mixer, and then coarse particles were removed through a 100-mesh sieve to obtain a magnetic toner 9. Table 3 shows the physical properties of the obtained magnetic toner 9.

[0181]   (Toner Comparative Production Example 2)   ・ Magnetic material (average particle size 0.22 μm) 90 parts   ・ Styrene-butyl acrylate-butyl maleate half ester copolymer     (Mn = 030,000, Mw = 200,000, molecular weight 2000 or less = 20%,       Molecular weight more than 1 million = 5%, glass transition point Tg = 59 ° C.) 100 parts   ・ Monoazo dye iron complex (negative charge control agent) 2 parts   ・ Low molecular weight polyolefin (release agent) 4 parts

Using the above materials, a finely divided powder was obtained in the same manner as in Toner Production Example 7. In comparison with the fine powder, untreated dry silica (B) having a primary particle diameter of 12 nm is used as an inorganic fine powder for surface fixation.
1.0 mass% of ET specific surface area 180 m ² / g),
Mixed with a mixer. Next, the mixture was subjected to surface treatment by thermo-mechanical impact force (treatment temperature 55 ° C.) to obtain magnetic toner particles, and coarse particles were removed through a 100 mesh sieve to obtain magnetic toner 10. Table 3 shows the physical properties of the obtained magnetic toner 10.

[0183]

[Table 3]

<Photoreceptor Production Example 3> The photoconductor was prepared according to the above-described photoreceptor production example 1 up to the charge generation layer. For the charge transport layer, a hole-transporting triphenylamine compound dissolved in a polycarbonate resin at a mass ratio of 10:10 was used. Film thickness 20 μm. Furthermore, as a protective layer, a polytetrafluoroethylene powder (particle size: 0.2 μm) was added to the composition obtained by dissolving the same material in a mass ratio of 5:10 in an amount of 30% with respect to the total solid content to obtain a uniform mixture. Was spray-coated on the charge transport layer. Film thickness 5 μm. The contact angle with water was 105 degrees.

Example 9 An image forming apparatus shown in FIG. 1 was used as the image forming apparatus.

As an electrostatic latent image carrier, the organic photoconductor (OPC) drum of Photoconductor Production Example 3 was used and the dark portion potential V _d = -70.
0V and bright part potential _VL = -210V. The gap between the photosensitive drum and the developing sleeve was 300 μm, the toner carrier had a layer thickness of about 7 μm and the JIS center line average roughness (Ra) was 1.8 μm, and the surface was blasted to form a resin layer having a diameter of 16φ. Using a developing sleeve formed on an aluminum cylinder, developing pole 95mT (950 gauss),
As a toner control member, thickness 1.0mm, free length 10mm
The urethane rubber blade of 14.7 N / m (15 g /
The contact was made with a linear pressure of (cm).

[0187]   Phenolic resin 100 parts   Graphite (particle size: about 7 μm) 90 parts   Carbon black 10 parts

Next, as a developing bias, a DC bias component V _dc = -500 V and an AC bias component V to be superimposed
_PP = 1600V and f = 2000Hz were used. Also,
The peripheral speed of the developing sleeve is the peripheral speed of the photoconductor (48 mm / sec).
120% speed in the forward direction (58 mm / se
c).

Further, a transfer roller as shown in FIG. 8 (made of ethylene-propylene rubber in which conductive carbon is dispersed, volume resistance value of conductive elastic layer 10 ⁸ Ωcm, surface rubber hardness 24)
°, diameter 20 mm, contact pressure 49 N / m (50 g / c
m)) is a constant speed with respect to the peripheral speed of the photoconductor (48 mm / sec), +2 kV is applied as the transfer bias, and magnetic toner 1 is used as the toner, and an image is output under the environment of 23 ° C. and 65% RH. I did. As the transfer paper, 75 g / m ² paper was used. At this time, the transfer efficiency from the photoconductor to the transfer material was as high as 98%, and there was no dropout of characters or lines in the transfer, and a good image with substantially no scattering on the image was obtained. Even after printing 5,000 sheets, the transfer efficiency was as high as 96%, and a good image was obtained.

Example 10 Image formation was carried out under the same apparatus conditions as in Example 9 except that magnetic toner 2 was used instead of magnetic toner 1. At this time, the transfer efficiency from the photoconductor to the transfer material was as high as 98%, and there was no omission of characters or lines during transfer, and a good image without scattering was obtained. After printing 5000 more sheets, it was almost as good as in Example 9.

Example 11 Image was produced under the same apparatus conditions as in Example 9 except that magnetic toner 3 was used instead of magnetic toner 1 and the OPC drum of Photoreceptor Manufacturing Example 1 was used as the electrostatic latent image carrier. I went. At this time, the transfer efficiency from the photoconductor to the transfer material was as high as 96%, and there was no omission of characters or lines during transfer, and a good image without scattering was obtained. 500 more
After printing 0 sheets, it was almost as good as in Example 9.

Example 12 Image formation was carried out under the same apparatus conditions as in Example 11 except that the magnetic toner 4 was used. At this time, the transfer efficiency from the photoconductor to the transfer material was as high as 95%, and there was no omission of characters or lines in the transfer, and a good image without scattering on the image was obtained. Example 9 even after printing 5000 sheets
Was almost as good as.

Comparative Example 4 Images were produced under the same apparatus conditions as in Example 11 except that the magnetic toner 5 was used. At this time, the transfer efficiency from the photoconductor to the transfer material was as high as 93%, and there was no dropout of characters or lines in the transfer, and a good image without scattering on the image was obtained. Further, although the transfer efficiency was slightly lowered after printing 5000 sheets, good results were obtained with no problem in practical use.

Comparative Example 5 Images were printed under the same apparatus conditions as in Example 11 except that the magnetic toner 6 was used. At this time, the transfer efficiency from the photoconductor to the transfer material was as high as 93%, and no characters or lines were missing in the transfer. A slight scattering was seen in the fine line portion on the image, but a good image with no problem in practical use was obtained.

Comparative Example 6 Image formation was carried out under the same apparatus conditions as in Example 11 except that the magnetic toner 7 was used. At this time, the transfer efficiency from the photoconductor to the transfer material was as high as 91%, and there was no omission of characters or lines during transfer, and a good image without scattering was obtained. Further, although the transfer efficiency was slightly lowered after printing 5000 sheets, good results were obtained with no problem in practical use.

Comparative Example 7 Images were printed under the same apparatus conditions as in Example 11 except that the magnetic toner 8 was used. At this time, the transfer efficiency from the photoconductor to the transfer material was as high as 90%, showing a high transfer efficiency, and in addition to the slightly low image density, no voids in the transfer of characters or lines were observed. Further, although the transfer efficiency was slightly lowered after printing 5000 sheets, good results were obtained with no problem in practical use.

Comparative Example 8 Image formation was performed under the same apparatus conditions as in Example 9 except that the magnetic toner 9 was used in place of the magnetic toner 1, and the OPC drum of Photoreceptor Manufacturing Example 2 was used as the electrostatic latent image bearing member. I went. At this time, the transfer efficiency from the photoconductor to the transfer material is as low as 85%,
In addition, an image in which voids in the transfer of characters and lines were conspicuous was obtained.

Comparative Example 9 Image formation was performed under the same apparatus conditions as in Comparative Example 1 except that the magnetic toner 10 was used. The transfer efficiency from the photoreceptor to the transfer material at this time was as low as 84%. Also, in a solid black image,
The image density was high only in the part corresponding to the circumference of the developing sleeve from the front end of the image, and the subsequent parts were unclear images with low image density.

[0199]

According to the present invention, the transferability is excellent, the transfer residual toner is small, and even in the roller transfer system, a void in the transfer does not occur, or a high density image in which these phenomena are suppressed can be obtained for a long time. In addition, it can be stably obtained even after printing a large number of sheets.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a configuration of a toner carrier used in the present invention.

FIG. 2 is an explanatory diagram of an example of an image forming apparatus used in the present invention.

FIG. 3 is an enlarged view of a main part of FIG.

FIG. 4 is an explanatory diagram showing an example of the configuration of a photoconductor used in the present invention.

FIG. 5 is an explanatory diagram of a charge amount measuring device for measuring a charge amount of toner used in the present invention.

FIG. 6 is a diagram showing a range of the present invention in shape factors SF-1 and SF-2.

FIG. 7 is a diagram showing a good image (a) having no transfer defects and a defective image (b) having transfer defects.

FIG. 8 is a diagram showing an example of a contact transfer member.

FIG. 9 is a diagram showing an example of a contact transfer member.

[Explanation of symbols]

1 Toner carrier 2 particles 3 Binder resin 4 Conductive substance 5 base 6 coating layer 100 photosensitive drum 102 developing sleeve (toner carrier) 103 Contact blade 104 magnet roller 114 Transfer charging roller 116 cleaner 117 Primary charging roller 140 developer 141 stir bar

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI G03G 5/147 502 G03G 5/147 502 504 504 9/083 15/02 101 15/02 101 9/08 101 15/08 507 15 / 08 507L (72) Inventor Yuki Karaki 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (56) Reference JP-A-61-279864 (JP, A) JP-A-8-184990 (JP , A) JP 7-152217 (JP, A) JP 6-313984 (JP, A) JP 6-167817 (JP, A) JP 5-142857 (JP, A) JP 5-142849 (JP, A) JP-A-4-204749 (JP, A) JP-A-2-284158 (JP, A) JP-A-1-185654 (JP, A) JP-A 1-113764 (JP, A) A) (58) Fields surveyed (Int.Cl. ⁷ , DB name) G03G 9/08

Claims (35)

(57) [Claims] 1. A substrate and at least a surface of a toner carrier
Particles for imparting roughness, conductive material and binder resin
It has a coating layer containing a center line average roughness of the surface is 0.2
To 4.5 μm toner carrier with elastic member
A toner used in an image forming method in which a toner layer thickness regulating member is brought into contact to form a thin layer of toner, and an electrostatic charge image on an electrostatic latent image carrier is developed while applying an alternating electric field to the toner in a developing section. The toner is a toner having at least toner particles in which a colorant is dispersed in a binder resin and an inorganic fine powder, and the shape factor SF-1 of the toner measured by an image analyzer is 110. <SF-1 ≦ 180, the value of the shape factor SF-2 is 110 <SF-2 ≦ 140, and the value B obtained by subtracting 100 from the value of SF-2 and the value obtained by subtracting 100 from the value of SF-1 are obtained. The ratio B / A with the value A is 1.0 or less, the specific surface area Sb (m ² / cm ³ ) of the toner per unit volume measured by the BET method, and the toner is assumed to be a true sphere. Per unit volume calculated from the weight average particle size Relationship between the specific surface area St (m ² / cm ³⁾ are satisfied, the following condition 3.0 ≦ Sb / St ≦ 7.0 Sb ≧ St × 1.5 + 1.5, the toner particles, the 1~100nm Integrated pore area of pores
A toner having a 60% pore radius in a ratio curve of 3.5 nm or less . 2. The toner according to claim 1, wherein the toner is a magnetic toner containing 30 to 200 parts by mass of a magnetic material with respect to 100 parts by mass of a binder resin. 3. SF measured by an image analyzer of the toner
The value of -1 is 120 to 160, and the value of SF-2 is 115 to 140. 3.
The toner according to. 4. The inorganic fine powder contained in the toner is at least one kind of inorganic fine powder selected from titania, alumina, silica, or a double oxide thereof. The toner according to any one. 5. The inorganic fine powder contained in the toner is hydrophobized.
5. The toner according to any one of 4 to 4. 6. The toner according to claim 5, wherein the hydrophobized inorganic fine powder contained in the toner is at least treated with silicone oil. 7. The inorganic fine powder contained in the toner has a primary particle diameter of 30 nm or less, and the fine powder having a primary particle diameter of more than 30 nm is added to the toner. The toner described. 8. The toner according to claim 7, wherein the fine powder exceeding 30 nm is an inorganic fine powder. 9. The toner according to claim 7, wherein the fine powder having a particle size exceeding 30 nm is a resin fine powder. 10. The toner according to claim 7, wherein the fine powder having a particle size of more than 30 nm is substantially spherical. 11. The specific surface area Sr per volume of the toner particles measured by the BET method is 1.2 to 2.5 m ^2.
The toner according to any one of claims 1 to 10, wherein the toner is / cm ³ . 12. A substrate and at least a toner carrier surface
Particles for imparting roughness to a conductive material, a binder resin, and
Have a coating layer containing a center line average roughness of the surface is zero.
The toner carrier having a thickness of 2 to 4.5 μm should be made of an elastic material.
A thin layer of toner is formed by contacting the toner layer thickness regulating member, and the electrostatic latent image is developed by developing an electrostatic charge image on the electrostatic latent image carrier while applying an alternating electric field to the toner in the developing section. A developing step for forming a toner image on the body; and a transferring step for transferring the toner image on the electrostatic latent image carrier onto the transfer material while bringing the transfer means to which a voltage is applied into contact with the transfer material. In the image forming method using an electrophotographic apparatus, the toner is a toner having at least toner particles in which a colorant is dispersed in a binder resin and an inorganic fine powder, and the shape factor SF of the toner measured by an image analysis apparatus. The value of −1 is 110 <SF-1 ≦ 180, the value of the shape factor SF-2 is 110 <SF-2 ≦ 140, and the value of SF-2 is 100 minus 100. The value of the ratio B / A with the value A minus 100 Is 1.0 or less, and a unit calculated from the specific surface area Sb (m ² / cm ³ ) per unit volume of the toner measured by the BET method and the weight average particle diameter when the toner is assumed to be a true sphere. The relationship of the specific surface area St (m ² / cm ³ ) per volume satisfies the following condition 3.0 ≦ Sb / St ≦ 7.0 Sb ≧ St × 1.5 + 1.5 , and the toner particles are 1 ~ 100 nm integrated pore area of pores
An image forming method, wherein the 60% pore radius in the ratio curve is 3.5 nm or less . 13. The image forming method according to claim 12, wherein the particles for imparting roughness to the surface of the toner carrier are spherical particles having a number average particle diameter of 0.05 to 100 μm. 14. The image forming method according to claim 12 , wherein the conductive substance is graphite, carbon black, or a mixture of graphite and carbon black. Claim contact angle for water of the surface of 15. latent electrostatic image bearing member is equal to or is more than 85 degrees 12
15. The image forming method according to any one of 14 to 14 . 16. A method according to claim 12 or 15, characterized in that it contains a substance containing fluorine to the surface of the latent electrostatic image bearing member
The image forming method according to any one of 1. 17. The image forming method according to claim 16, wherein the substance containing fluorine on the surface of the electrostatic latent image carrier is fine powder containing fluorine. 18. The image forming method according to any one of claims 12 to 17 charging member that charges the latent electrostatic image bearing member is characterized in that it is in contact with the electrostatic latent image bearing member. 19. The toner according to any one of claims 2 to 11.
A contract characterized in that it is the toner described in any one of them.
The image forming method according to claim 12. 20. A toner in which a colorant is dispersed in at least a binder resin, and a toner particle having an inorganic fine powder 1 adhered to the surface thereof and an inorganic fine powder 2 are externally added and mixed. The value of the shape factor SF-1 measured by the image analyzer is 110 <SF-1 ≦ 180, and the shape factor SF−
The value of 2 is 110 <SF-2 ≦ 140, and the value of the ratio B / A of the value B obtained by subtracting 100 from the value of SF-2 and the value A obtained by subtracting 100 from the value of SF-1 is 1. 0 or less, and the specific surface area Sb (m ² / cm ³ ) per unit volume of the toner measured by the BET method and the unit surface area per unit volume calculated from the weight average particle diameter when the toner is assumed to be a true sphere. The relationship of the specific surface area St (m ² / cm ³ ) satisfies the following condition 3.0 ≦ Sb / St ≦ 7.0 Sb ≧ St × 1.5 + 1.5, and the toner has a weight average particle diameter of 4 ~ 8 μm, particle size 10
A toner having a ratio of the toner particles having a particle size of more than μm of 0.9 to 4.8% by volume. To 21. The toner binder resin 100 parts by mass, toner according to claim 20, characterized in that a magnetic toner containing a magnetic material 30 to 200 parts by weight. 22. S measured by an image analyzer of the toner
The toner according to claim 20 or 21 , wherein the value of F-1 is 120 to 160, and the value of SF-2 is 115 to 140. 23. The method of claim, wherein the inorganic fine powder 1 and 2 contained in the toner is titania, alumina, silica or one or more inorganic fine powder selected from the mixed oxide 20 23. The toner according to any one of 22 to 22 . 24. The toner according to any one of claims 20 to 23 , wherein the inorganic fine powders 1 and 2 contained in the toner have been hydrophobized. The toner according to claim 24 in which at least one of 25. hydrophobized inorganic fine powder contained in the toner, characterized in that it is obtained by treatment with at least silicone oil. 26. The inorganic fine powder 1 contained in the toner
When the primary particle diameter of 2 is at 30nm or less, and the toner according to any one of claims 20 to 25, characterized in that it further comprises a fine powder 3 of more than 30nm. 27. The toner according to claim 26 , wherein the fine powder 3 having a particle size of more than 30 nm is an inorganic fine powder. 28. The toner according to claim 26 , wherein the fine powder 3 having a particle size of more than 30 nm is a resin fine powder. 29. The toner according to any one of claims 26 to 28 fine powder 3 more than the 30nm is characterized by a substantially spherical. 30. A developing step of forming a toner image on the electrostatic latent image carrier; and a step of contacting a transfer means to which a voltage is applied with a transfer material with the toner image on the electrostatic latent image carrier. In an image forming method using an electrophotographic apparatus having a transfer step of transferring onto a transfer material, the toner comprises at least a colorant dispersed in a binder resin, and a surface of which an inorganic fine powder 1 is fixed. A toner in which particles and the inorganic fine powder 2 are externally mixed, and the value of the shape factor SF-1 measured by an image analyzer of the toner is 110 <SF-1 ≦ 180, and the value of the shape factor SF-2. Is 110 <SF-2 ≦ 140, and the ratio B / A of the value B obtained by subtracting 100 from the value of SF-2 and the value A obtained by subtracting 100 from the value of SF-1 is 1.0 or less. Yes, the unit volume warmth of the toner measured by the BET method A specific surface area Sb (m ² / cm ³⁾ of the relationship is the following conditions of the specific surface area St per unit volume calculated from the weight average particle diameter when assuming a toner and sphericity ^{(m 2 / cm 3) 3} . 0 ≦ Sb / St ≦ 7.0 Sb ≧ St × 1.5 + 1.5 is satisfied, and the toner has a weight average particle diameter of 4 to 8 μm and a particle diameter of 10
An image forming method, wherein the ratio of the toner particles having a particle size of more than μm is 0.9 to 4.8% by volume. Claim contact angle for water of the surface of 31. latent electrostatic image bearing member is equal to or is more than 85 degrees 30
The image forming method described in 1 .. 32. Claim 30 or 31, characterized in that it contains a substance containing fluorine to the surface of the latent electrostatic image bearing member
The image forming method described in 1 .. 33. The image forming method according to claim 32, wherein the substance containing fluorine on the surface of the electrostatic latent image bearing member is fine powder containing fluorine. 34. The image forming method according to any one of claims 30 to 33 charging member that charges the latent electrostatic image bearing member is characterized in that it is in contact with the electrostatic latent image bearing member. 35. The toner according to any one of claims 21 to 29.
The toner is the toner described in one item.
The image forming method according to claim 30.