JP2010197472A - Electrophotographic toner and image forming apparatus using the same, process cartridge, and image forming method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a toner, an image forming method, an apparatus and process a cartridge excellent in cleaning properties, non-filming properties and low temperature fixability and capable of forming an image of high picture quality even in a high-speed process. <P>SOLUTION: The toner comprises toner base particles containing a fixing resin and a charge control agent containing a non-molybdenum quaternary ammonium salt, and an external additive on the surfaces of the particles. The toner is controlled to have a weight average particle diameter of 2 to 10 μm and an absolute charge amount of 4 to 25 μC/g (by a suction blow-off method). The toner is used in the following image forming apparatus to form an image at a high line speed. The image forming apparatus includes at least an image carrier and a brush rotator which is in contact with the image carrier and cleans the toner on the image carrier while rotating in a direction following the rotation of the image carrier or in the reverse direction, wherein a relative velocity difference ¾(A)-(B)¾ between the circumferential velocity (A) of the image carrier and the circumferential velocity (B) of the brush rotator [B: with a sign "+" when the rotation direction follows the rotation of the image carrier, and a sign "-" when the rotation direction is in the reverse direction] is controlled to the range from 1,500 to 15,00 mm/s. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an electrophotographic toner for visualizing an electrostatic charge latent image formed on the surface of an image carrier in an electrophotographic method, an electrostatic printing method, an electrostatic recording method or the like, and an image carrier using the toner. The present invention relates to an image forming apparatus such as a copying machine, a printer, and a facsimile that visualizes an electrostatic latent image formed on a body surface, a process cartridge, and an image forming method.

As an electrophotographic method used in image forming apparatuses such as laser printers and dry electrostatic copying machines, the surface of an image carrier such as a photoconductive layer is uniformly charged, and then the surface of the image carrier is exposed and exposed. An electric latent image is formed by dissipating the electric charge of the formed portion, and further visualized by attaching a fine powder having a charge called toner to the latent image, and the obtained visible image is transferred. After the transfer to a transfer material such as paper, the process includes a step of permanently fixing by heating, pressurizing, and the like and cleaning fine powder remaining on the surface of the image carrier without being transferred.
In recent image forming apparatuses, there are increasing demands for energy saving at the time of toner fixing and image forming apparatuses capable of processing at high speed, and the toner itself is required to have a property of melting at a low temperature.
On the other hand, image forming apparatuses are also required to perform processes such as exposure, charging, transfer, fixing, and cleaning at high speeds due to demands for higher speeds.

Regarding improvement of the toner, for example, as described in Patent Document 1, an initial maximum endothermic peak (A) by DSC measurement (40 to 75 ° C.) and a maximum endothermic peak (B) after storage at 40 ° C. for 72 hours are obtained. By controlling (5 ≦ B−A ≦ 13), a method has been proposed in which low temperature fixability, heat resistant storage stability and offset resistance are improved, and dispersion and grindability improvement of the toner composition are simultaneously achieved.
Alternatively, as described in Patent Document 2, the toner containing 1 to 20% by weight of paraffin wax having a peak position of absorption heat amount by DSC measurement at 75 to 85 ° C. A method for improving the non-offset property has been proposed.

Conventionally, non-magnetic one-component toner that does not use a magnetic carrier is frequently used in general-purpose laser printers, and a magnetic brush developing method using a two-component developer is generally used in high-speed laser printers.
In an image forming apparatus having a brush-like rotator in the cleaning process, the cleaning performance is determined by the ratio of the speed of the surface of the image carrier and the speed of the brush-like rotator, and as the relative speed of the brush rotation speed increases, the image carrier There is a report that cleaning is performed at a relative speed ratio within a certain range because the surface of the toner cannot be cleaned and toner fixation called filming is observed in a long-term operation.
For example, Patent Document 3 proposes a cleaning device that removes toner under optimum cleaning conditions even when the rotation speed of the fur brush is changed by a motor equipped with an irregular device and the printing speed is switched.
Patent Document 4 proposes a method for efficiently removing residual toner by a cleaning device including a cleaning brush (upstream side) that generates fine toner and a cleaning blade (downstream side) that scrapes off the toner. Yes.

  However, the demand for higher speed is greater than before, and when the speed of the image carrier is increased, the brush rotational speed is required to be very high, which is mechanically large, Problems such as defective cleaning and filming occur, and it is difficult to cope with the proposed prior art.

  The present invention has been made in order to solve the problems in the image forming apparatus of the high-speed system, and its purpose is excellent in cleaning property and non-filming property (preventing toner filming) and at low temperature. An object of the present invention is to provide a toner (including a two-component developer) capable of forming a high-quality image even in high-speed printing repeatedly, and an image forming apparatus, a process cartridge, and an image forming method using the toner.

  As a result of intensive studies, the present inventors have found that the above problems can be solved by the inventions described in the following [1] to [13], and have reached the present invention. Hereinafter, the present invention will be specifically described.

[1]: The above-described problem is at least an image carrier and a brush-like rotator that contacts the image carrier and cleans the toner on the image carrier while rotating in the forward or reverse direction with the image carrier. A relative speed difference (| (A) − (B) |) between the peripheral speed (A) of the image carrier and the peripheral speed (B) of the brush-like rotating body is 1,500 to 15,000 mm / s. An electrophotographic toner used in an image forming apparatus defined as a range,
The toner contains a charge control agent containing at least a non-molybdenum-based quaternary ammonium salt and a fixing resin, and the toner has a weight average particle diameter in the range of 2 to 10 μm, and an absolute value of the charge amount is 4 It is solved by an electrophotographic toner characterized by being in the range of ˜25 μc / g.

  [2]: The electrophotographic toner as described in [1] above, wherein the electrophotographic toner contains a lubricant.

  [3]: The electrophotographic toner according to the above [2], wherein the lubricant is contained both in the toner and in the toner surface layer.

  [4]: The electrophotographic toner according to [3], wherein the lubricant contained in the toner contains a fatty acid amide lubricant and a fatty acid lubricant.

  [5]: In the electrophotographic toner according to the above [3] or [4], the lubricant contained in the toner contains a fatty acid amide-based lubricant, and the lubricant contained in the toner surface layer portion is It contains a fatty acid metal salt lubricant.

  [6]: In the electrophotographic toner according to any one of [1] to [5], the electrophotographic toner has an endothermic peak measured by a differential scanning calorimeter at 60 to 90 ° C. and 90 to 90 ° C. It has at least one in each temperature range of 120 degreeC and 120-140 degreeC, It is characterized by the above-mentioned.

  [7]: The electrophotographic toner according to any one of [1] to [6], wherein the electrophotographic toner is a color toner and / or a transparent toner.

  [8]: The electrophotographic toner according to any one of [1] to [7], wherein the electrophotographic toner is used as a two-component developer together with a carrier.

  [9]: In the electrophotographic toner according to any one of [1] to [8], a peripheral speed of the image carrier is 800 mm / s or more.

  [10]: In the electrophotographic toner according to any one of [1] to [9], a peripheral speed of the image carrier is 1,700 mm / s or more.

[11]: At least the image carrier, the charging unit for charging the surface of the image carrier, the exposure unit for exposing the charged surface of the image carrier to form an electrostatic latent image, and the formed electrostatic latent Developing means for developing toner by attaching toner to the image, transfer means for transferring the developed toner image to a recording medium, and contacting the image carrier after transfer and rotating in the forward or reverse direction with the image carrier. A cleaning means comprising a brush-like rotator for cleaning the toner on the image carrier, and a relative speed difference (| () (A) between the peripheral speed (A) of the image carrier and the peripheral speed (B) of the brush-like rotator. A)-(B) |) is an image forming apparatus in a range of 1,500 to 15,000 mm / s,
The toner is an electrophotographic toner described in any one of [1] to [10].

[12]: At least the image carrier, a charging unit for charging the surface of the image carrier, an exposure unit for exposing the charged image carrier surface to form an electrostatic latent image, and the electrostatic Developing means for attaching toner to the latent image and developing, transfer means for transferring the developed toner image to a recording medium, and contacting the image carrier after transfer and rotating in the forward or reverse direction with the image carrier And a process cartridge that can be attached to and detached from the image forming apparatus main body integrated with at least one means selected from cleaning means including a brush-like rotating body that cleans the toner on the image carrier,
The relative speed difference (| (A)-(B) |) between the peripheral speed (A) of the image carrier and the peripheral speed (B) of the brush-like rotating body is in the range of 1,500 to 15,000 mm / s. In addition, the process cartridge is characterized in that the toner to be adhered is the electrophotographic toner according to any one of [1] to [10].

[13]: The above-described problems include a step of charging at least the image carrier with a charging unit, a step of forming an electrostatic latent image on the surface of the image carrier with an exposure unit, and a toner on the electrostatic latent image with a developing unit. And developing the toner image as a toner image; transferring the developed toner image to a recording medium by a transfer unit; fixing the transferred toner image by a fixing unit; and after the transfer step, An image forming method comprising a step of cleaning toner on an image carrier by a cleaning means comprising a brush-like rotator while contacting the image carrier and rotating in the forward or reverse direction with the image carrier,
The relative speed difference (| (A)-(B) |) between the peripheral speed (A) of the image carrier and the peripheral speed (B) of the brush-like rotating body is in the range of 1,500 to 15,000 mm / s. The image forming method is characterized in that the toner to be adhered is the electrophotographic toner according to any one of claims 1 to 10.

The toner of the present invention contains at least a charge control agent (including a non-molybdenum quaternary ammonium salt) and a fixing resin, and has an average particle diameter (2 to 10 μm) and an absolute value of charge amount (4 to 25 μc / g). ) Is controlled, no toner cleaning failure occurs and toner adheres even if printing is repeated using a high-speed image forming apparatus configured to clean the toner on the image carrier with a brush-like rotating body. High anti-offset performance and fixing strength are ensured even during low-temperature fixing, and it does not depend on the usage environment in high-temperature, high-humidity or low-temperature, low-humidity environments. Image formation with high image quality is possible. Even when used as a two-component developer together with a carrier, the occurrence of carrier spent is suppressed.
According to the image forming apparatus, process cartridge, and image forming method using the toner of the present invention, a stable high-quality image can be obtained without the occurrence of defective cleaning or filming even when the process linear speed is repeatedly used. Can output continuously. Here, if a process cartridge is used, it is easy to store, transport, etc., and exchanging in a short time is excellent in handling.

1 is a schematic diagram illustrating a configuration example of an image forming apparatus according to the present invention.

As described above, the electrophotographic toner of the present invention cleans at least the image carrier and the toner on the image carrier while contacting the image carrier and rotating in the forward or reverse direction with the image carrier. A brush-like rotator is provided, and the relative speed difference (| (A)-(B) |) between the peripheral speed (A) of the image carrier and the peripheral speed (B) of the brush-like rotator is 1,500-15. An electrophotographic toner used in an image forming apparatus having a range of 1,000,000 mm / s,
The toner contains a charge control agent containing at least a non-molybdenum-based quaternary ammonium salt and a fixing resin, and the toner has a weight average particle diameter in the range of 2 to 10 μm, and an absolute value of the charge amount is 4 It is in the range of ˜25 μc / g.
In the above, the peripheral speed (B) is a plus sign for forward rotation with the image carrier (photoreceptor), and a minus sign for backward rotation.
In addition, the toner in the present invention has, for example, a toner base particle containing at least a charge control agent (including a non-molybdenum-based quaternary ammonium salt) and a fixing resin and an external additive on the surface thereof. it can.

  As a result of intensive studies, the present inventors have found that in an image forming apparatus having an image carrier and a brush-like rotator that rotates in contact with the image carrier, the rotational speed of the image carrier, so-called peripheral speed (A ) And the relative speed difference (| (A) − (B) |) of the peripheral speed (B) of the brush-like rotating body that cleans the toner on the image bearing body while rotating in the forward or reverse direction with the image bearing body. ) Exceeds 15,000 mm / s, among the toner once separated from the image carrier and moved to the brush of the brush-like rotating body, the toner that cannot be completely peeled off (or detached) from the brush again The present inventors have found a filming mechanism in which toner filming is formed on the surface of the image carrier by rubbing the image carrier at high speed.

  In other words, the toner formed along the latent image on the surface of the image carrier is transferred to a transfer material such as transfer paper, but at that time, the toner is not 100% transferred and partly remains on the surface of the image carrier. To do. The remaining toner is brought into contact with a fur brush, which is a brush-like rotating body, and moves to the brush side. Originally, the toner that has moved to the brush should be completely removed from the brush before it comes into contact with the image carrier again by a dust collector or the like, but it cannot be completely removed because the rotational speed of the brush itself is high. There is. In this case, since the toner remaining on the brush again comes into contact with the image carrier again at high speed, the toner adheres to the surface of the image carrier due to pressure, frictional heat, etc., melts, solidifies, and forms a film on the image carrier. Also, depending on the material and hardness of the brush, when the image carrier and the brush are brought into contact at high speed, fine scratches are generated on the surface of the image carrier, or the fine scratches become nuclei (factors) that cause toner separation. Deterioration of moldability causes cleaning failure and filming.

  As a result of investigations by the present inventors, when the relative speed difference between the peripheral speed (A) of the image carrier and the peripheral speed (B) of the brush-like rotating body exceeds 15,000 mm / s, fine scratches are formed on the surface of the photoreceptor. On the other hand, when the relative speed difference between the peripheral speed (A) of the image carrier and the peripheral speed (B) of the brush-like rotating body is less than 1500 mm / s, the cleaning performance is poor and the toner remains on the surface of the image carrier. It has been found that the relative speed difference (| (A) − (B) |) is preferably in the range of 1,500 to 15,000 mm / s.

However, even if the relative speed difference between the peripheral speed (A) of the image carrier and the peripheral speed (B) of the brush-like rotating body is in the range of 1,500 to 15,000 mm / s, toner having poor cleaning properties is used. In such a case, toner cleaning failure may occur.
For this reason, as a result of intensive studies, the inventors have found that when the absolute value of the charge amount of the toner is 25 μc / g or less, toner cleaning failure does not occur under the condition of the relative speed difference.
That is, when the absolute value of the toner charge amount is greater than 25 μc / g, it becomes difficult to disperse from the image carrier, resulting in poor cleaning. On the other hand, if the absolute value of the charge amount of the toner is smaller than 4 μc / g, fog occurs, and the toner adheres to the non-image portion, which tends to cause printing failure. Therefore, in the present invention, the absolute value of the charge amount of the toner is preferably in the range of 4 to 25 μc / g.
The toner charge amount in the present invention is specifically measured as follows.
In the case of a two-component developer, use a TB-203 type charge amount measuring device manufactured by Kyocera Chemical Co., Ltd., weigh about 0.2 g of the two-component developer into a Faraday gauge, and suck and inject nitrogen gas into the two-component developer. The toner in the developer is separated. The charge amount at that time is recorded, and the charge amount is measured using the difference in weight before and after the measurement as the toner weight. At this time, the opening of the wire mesh in the Faraday gauge is set such that the carrier does not pass through.
In the case of a one-component developer, a charge type small charge amount measuring device manufactured by Trek Japan Co., Ltd. is used, and the charge amount is measured by the charge amount and weight difference of a small Faraday gauge.

In the present invention, a charge control agent comprising a non-molybdenum-based quaternary ammonium salt is blended into the toner as an essential component, and the absolute value of the charge amount of the toner is controlled in the range of 4 to 25 μc / g.
Here, as the non-molybdenum-based quaternary ammonium salt, tributylbenzylammonium-1-hydroxy-4-naphthosulfonic acid, tetrabutylammonium tetrafluoroborate, benzoylmethylhexadecylammonium chloride, decyltrimethyl chloride, fluorinated tetra A quaternary ammonium salt such as a quaternary ammonium salt can be used, but is not limited thereto. By using these non-molybdenum-based quaternary ammonium salts, fluctuations in the toner charge amount in high-temperature and high-humidity environments and low-temperature and low-humidity environments can be reduced. Can be prevented.

As the charge control agent, a charge control agent other than the non-molybdenum-based quaternary ammonium salt can be used in combination.
Examples of charge control agents other than such non-molybdenum-based quaternary ammonium salts include modified products of nigrosine and fatty acid metal salts, onium salts such as phosphonium salts and lake pigments thereof, triphenylmethane dyes and lake lake pigments thereof , Metal salts of higher fatty acids; diorganotin oxides such as dibutyltin oxide, dioctyltin oxide, dicyclohexyltin oxide, diorganotin borates such as dibutyltin borate, dioctyltin borate, dicyclohexyltin borate, organometallic complexes, chelate compounds, monoazo There are metal complexes, acetylacetone metal complexes, aromatic hydroxycarboxylic acids, and aromatic dicarboxylic acid metal complexes. Others include aromatic hydroxycarboxylic acids, aromatic mono- and polycarboxylic acids and their metal salts, anhydrides, esters, and phenol derivatives such as bisphenol. These may be used alone or in combination of two or more with a non-molybdenum quaternary ammonium salt.

  When these charge control agents are internally added to the toner (added to the toner base particles), it is preferable to add 0.1 to 10 wt% with respect to the fixing resin. Further, since it may be colored depending on the kind of the charge control agent, it is preferable to select a white or transparent color as much as possible for the color toner and the transparent toner. Since some charge control agents have skin sensitization depending on the structure, it is necessary to carefully examine and select them.

The toner used in the present invention has an average particle diameter (weight average particle diameter) in the range of 2 to 10 μm. That is, if the weight average particle size is less than 2 μm, the fluidity, transferability, and cleaning properties of the toner tend to deteriorate. On the other hand, if the weight average particle size exceeds 10 μm, the image sharpness and fine line reproduction are reduced. Tend to deteriorate.
The average particle diameter of the toner is measured by various methods. In the present invention, the average particle diameter (weight average particle diameter) is obtained by measuring the number distribution and volume distribution using Coulter Counter Multisizer III. At this time, a measurement sample was prepared by adding a measurement toner in an electrolyte solution to which a surfactant was added and dispersing it with an ultrasonic disperser for 1 minute. Using this measurement sample, 50,000 toner particles were measured and averaged. The particle size (weight average particle size) was used.

Further, the electrophotographic toner in the present invention may contain a lubricant. In this case, the lubricant is preferably contained in both the toner inside and the toner surface layer. That is, it is desirable that the toner be contained in both the toner base (toner base particles) and the surface layer portion thereof (for example, a layer formed by an external additive is also included).
Here, the lubricant contained in the toner preferably includes a fatty acid amide lubricant and a fatty acid lubricant. Alternatively, it is preferable that the lubricant contained in the toner base particles contains a fatty acid amide-based lubricant, and the lubricant contained in the toner surface layer portion contains a fatty acid metal salt lubricant.
As the above-mentioned lubricant, a material having a so-called releasing effect is used. For example, liquid paraffin, microristane wax, natural paraffin, synthetic paraffin, polyolefin wax, and partial oxides thereof, fluoride, chloride, etc. Aliphatic hydrocarbon lubricants; animal oil such as beef tallow and fish oil; palm oil, soybean oil, rapeseed oil, rice bran wax, carnauba wax and other vegetable oils; montan wax and other higher aliphatic alcohols and higher fatty acid lubricants (fatty acid lubricants) ); Fatty acid amide type lubricants such as fatty acid amide and fatty acid bisamide; zinc stearate, calcium stearate, magnesium stearate, aluminum stearate, zinc oleate, zinc palmitate, magnesium palmitate, zinc myristate, zinc laurate, behenic acid Metal soap-based lubricants such as lead (fatty acid metal salt lubricant); fatty acid ester lubricant, such as polyvinylidene fluoride is not intended to be limited to be used.

  The lubricant may be used alone or in combination of two or more. When it is contained inside the toner (in the toner base particles), it is 0.1 to 10 parts by weight, preferably 1 to 5 parts by weight with respect to 100 parts by weight of the fixing resin. It can contain in the range of. By containing a lubricant inside the toner, good anti-offset performance and fixing strength at the time of fixing can be obtained, and a high rubbing test strength can be obtained. Thereby, when used in a high-speed image forming apparatus, low-temperature fixability can be secured. When the amount added is less than 0.1 parts by weight, offset tends to occur, and when it exceeds 10 parts by weight, carrier spent tends to occur and the image quality tends to deteriorate.

  When a lubricant is contained in the toner surface layer portion (for example, a layer made of an external additive formed on the surface of the toner base particles as described above can be used as the surface layer portion), the amount is 0 with respect to 100 weight parts of the fixing resin. 0.0001 to 1 part by weight, preferably 0.01 to 0.3 part by weight. When the toner surface layer contains a lubricant, the lubricant comes into direct contact with the image bearing member, so that a thin film is formed on the surface of the image bearing member, which is effective in easily removing the toner and preventing re-adhesion.

It is preferable that the electrophotographic toner has at least one endothermic peak measured by a differential scanning calorimeter in any of the temperature ranges of 60 to 90 ° C, 90 to 120 ° C, and 120 to 140 ° C.
That is, by using an electrophotographic toner having an endothermic peak in three temperature ranges of 60 to 90 ° C., 90 to 120 ° C., and 120 to 140 ° C., it has high low temperature fixability in a wide fixing temperature range even in high-speed image formation. Hot offset resistance can be maintained, cleaning defects and filming can be prevented, and required characteristics such as heat-resistant storage stability (preventing carrier spent) and development stability (rubbing strength) can be ensured.
The endothermic peak of the toner for electrophotography can be measured by a differential scanning calorimeter (DSC). The endothermic peak in the toner of the present invention is heated up to 200 ° C. and from 200 ° C. to 20 ° C. at 10 ° C./min. After cooling and taking a previous history, the temperature can be raised at a rate of 10 ° C./min, and it can be determined from the absorption heat quantity curve at that time.

Furthermore, the electrophotographic toner of the present invention can have an external additive (external additive) on the surface of the toner base particles as described above.
As the external additive, various materials are used, and a lubricant can be used as described above. For example, silica, Teflon (registered trademark) resin powder, polyvinylidene fluoride powder, cerium oxide powder, silicon carbide powder An abrasive such as strontium titanate powder, or a fluidity-imparting agent such as titanium oxide powder or aluminum oxide powder, an aggregation inhibitor, a resin powder, or a carbon black powder, zinc oxide powder, antimony oxide powder, oxidation, etc. A conductivity-imparting agent such as tin powder can be used, and white and black fine particles having opposite polarity can also be used as a developability improver. These can be used singly or in combination, and are selected so as to have resistance against development stress such as idling.

The electrophotographic toner of the present invention contains a fixing resin. Examples of the fixing resin used in the toner of the present invention include the following resins.
Styrene such as polystyrene, poly-p-chlorostyrene, and polyvinyltoluene, and substituted homopolymers thereof; styrene-p-chlorostyrene copolymer, 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 Styrene-based copolymers such as copolymers, styrene-vinyl methyl ketone copolymers, styrene-butadiene copolymers, styrene-isoprene copolymers, styrene-acrylonitrile-indene copolymers; Resin, natural modified Fe Resin, natural resin-modified maleic acid resin, acrylic resin, methacrylic resin, polyvinyl acetate, silicone resin, polyester resin, crystalline polyester resin, polyurethane, polyamide resin, furan resin, epoxy resin, xylene resin, polyvinyl butyral, terpene Examples thereof include resins, chroman-indene resins, and petroleum resins, and polyester resins are preferable.

  Further, a low hygroscopic resin obtained by graft copolymerizing styrene and / or acrylic acid derivative (styrene polymer or styrene copolymer) with the above-described polyester resin can also be used. The styrene polymer or styrene copolymer may be cross-linked or a mixed resin. In order to fix at low temperature and prevent high temperature offset, for example, in the case of styrene and / or (meth) acrylic resin, it consists of a high molecular weight polymer and a low molecular weight polymer. Is effective in securing fixing strength. The balance of the composition of both the high molecular weight polymer and the low molecular weight polymer is important for achieving both low-temperature fixability and offset resistance, and also affects storage stability.

The polyester resin can be obtained, for example, by dehydrating condensation of a dicarboxylic acid and a diol.
Dicarboxylic acids include dicarboxylic acids such as phthalic anhydride, terephthalic acid, isophthalic acid, orthophthalic acid, maleic acid, maleic anhydride, adipic acid, fumaric acid, itaconic acid, citraconic acid, succinic acid, malonic acid, glutaric acid, Alternatively, a derivative thereof or an ester compound thereof can be used.

  Examples of the diol include ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, butanediol, pentanediol, hexanediol, bisphenol A, polyoxyethylene- (2.0) -2,2-bis (4 -Hydroxyphenyl) propane and derivatives thereof, polyoxypropylene- (2.0) -2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene- (2.2) -polyoxyethylene- (2,0 ) 2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene- (6) -2,2-bis- (4-hydroxyphenyl) propane, polyoxypropylene- (2.2) -2,2- Bis- (4hydroxyphenyl) propane, polyoxypro Len- (2.4) -2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene- (3.3) -2, -bis (4-hydroxyphenyl) propane and its derivatives, polyethylene glycol, Polypropylene glycol, ethylene oxide-propylene oxide random copolymer diol, ethylene oxide-propylene oxide block copolymer diol, ethylene oxide-tetrahydrofuran copolymer diol, polycaprolactone diol, and the like can be used.

  Furthermore, the polyester is a tri- or higher functional carboxylic acid such as trimellitic acid, trimellitic anhydride, pyromellitic acid, pyromellitic anhydride, or a derivative thereof, or an esterified product thereof together with the dicarboxylic acid and diol. Or sorbitol, 1,2,3,6-hexanetetraol, 1,4-sorbitan, pentaerythritol, 1,2,4-butanetriol, 1,2,5-pentanetriol, glycerin, 2-methylpropanetriol A trihydric or higher functional polyhydric alcohol such as 2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane, 1,3,5-trimethylolbenzene and the like is obtained by dehydration condensation by a conventional method. be able to.

Further, in order to improve the compatibility between the fixing resin and the lubricant, when synthesizing the fixing resin, it may be synthesized by applying a co-polymerization method in which the lubricant is present in all or part of the synthesis. .
In the method of synthesizing the fixing resin by the coexistence polymerization method in the presence of the lubricant, the vinyl copolymer includes, as its constituent unit, a styrene monomer and / or a (meth) acrylate monomer, Other vinyl monomers can be included.
By performing the coexistence polymerization in which the lubricant in the present invention coexists in all or part of the synthesis, a vinyl copolymer in which the lubricant is uniformly dispersed can be obtained as at least a component thereof.

The vinyl copolymer (hereinafter also referred to as “vinyl polymer”) is mainly a monomer having two or more polymerizable double bonds, such as divinylbenzene, divinylnaphthalene. , Ethylene glycol dimethacrylate, 1,3-butanediol dimethacrylate, divinylaniline, divinyl ether, divinyl sulfide, divinyl sulfone and the like may be partially crosslinked.
Specific examples of the styrene monomer used as the constituent unit of the vinyl polymer include orthomethyl styrene, metamethyl styrene, alphamethyl styrene, 2,4-dimethyl styrene and the like in addition to styrene. .

  Specific examples of the acrylic acid ester or methacrylic acid ester monomer as the structural unit of the vinyl polymer include methyl acrylate, ethyl acrylate, propyl acrylate, n-butyl acrylate, isobutyl acrylate, acrylic acid n-octyl, dodecyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, In addition to acrylic acid such as stearyl methacrylate or alkyl esters of methacrylic acid, 2-chloroethyl acrylate, phenyl acrylate, methyl α-chloroacrylate, phenyl methacrylate, dimethylaminoethyl methacrylate Examples include diethylaminoethyl methacrylate, 2-hydroxyethyl methacrylate, glycidyl methacrylate, bisglycidyl methacrylate, polyethylene glycol dimethacrylate, methacryloxyethyl phosphate, and the like. Ethyl acrylate, propyl acrylate, butyl acrylate, methacrylic acid Methyl, ethyl methacrylate, propyl methacrylate, butyl methacrylate and the like are particularly preferably used.

  Examples of other vinyl monomers used as the structural unit of the vinyl polymer include acrylic acid such as acrylic acid, methacrylic acid, α-ethylacrylic acid, and crotonic acid, and α- or β-alkyl derivatives thereof, fumaric acid. , Unsaturated dicarboxylic acids such as maleic acid, citraconic acid, itaconic acid and their monoester derivatives and diester derivatives, succinic acid monoacryloyloxyethyl ester, succinic acid monomethacryloyloxyethyl ester, acrylonitrile, methacrylonitrile, acrylamide, etc. be able to.

The toner for electrophotography in the present invention can be used as a transparent toner, or can be used as a color toner containing a colorant as required.
As the colorant, all known dyes and pigments can be used, for example, carbon black, aniline black, acetylene black, naphthol yellow, hansa yellow, rhodamine lake, alizarin lake, bengara, phthalocyanine blue, indanthrene blue, quinacridone. , Naphthol red, benzimidazolone, and the like, but are not limited thereto. These are used in an amount necessary and sufficient to maintain the optical density or color tone of the fixed image, and preferably 0.2 to 25% by weight based on the resin. Further, a dye is used for the same purpose. For example, there are azo dyes, anthraquinone dyes, xanthene dyes, and methine dyes, and these can be added in an amount of 0.2 to 25% by weight based on the resin.

The toner for electrophotography of the present invention can be used as a two-component developer together with a carrier (hereinafter sometimes referred to as “magnetic carrier”).
When applying the two-component developer method, the magnetic fine particles constituting the magnetic carrier to be used are spinel ferrites such as magnetite and gamma iron oxide, and metals other than iron (Mn, Ni, Zn, Mg, Cu, etc.) Magnetoplumbite type ferrite such as spinel ferrite and barium ferrite containing two or more kinds, and iron or alloy particles having an oxide layer on the surface can be used.
The shape of the magnetic fine particles may be any of granular, spherical and acicular. In particular, when high magnetization is required, it is preferable to use ferromagnetic fine particles such as iron. In view of chemical stability, it is preferable to use magnetoplumbite type ferrites such as spinel ferrite and barium ferrite containing magnetite and gamma iron oxide. A resin carrier having a desired magnetization can also be used by selecting the type and content of the ferromagnetic fine particles. The magnetic properties of the carrier at this time, that is, the magnetization intensity at 1,000 oersteds is preferably 30 to 150 emu / g.

  The resin carrier as described above is manufactured by spraying a melt-kneaded product of magnetic fine particles and an insulating binder resin with a spray dryer, or reacting a monomer or prepolymer in an aqueous medium in the presence of the magnetic fine particles, It can be manufactured by curing. That is, a resin carrier in which magnetic fine particles are dispersed in a condensation type binder can be produced.

Chargeability can be controlled by fixing positively or negatively charged fine particles or conductive fine particles on the surface of the magnetic carrier, or coating a resin.
Silicone resin, acrylic resin, epoxy resin, fluorine resin, etc. are used as the coating material on the surface, and it can be coated with positively or negatively charged fine particles or conductive fine particles. Silicone resin and acrylic resin Is preferred.
The mixing ratio of the electrophotographic toner of the present invention to the magnetic carrier is preferably 2 to 10 wt% as the toner concentration.

  In order to prepare the toner for electrophotography in the present invention, first, a fixing resin, a non-molybdenum-based quaternary ammonium salt, a lubricant, a colorant as necessary, and a non-molybdenum-based quaternary ammonium salt as necessary. Combine the materials that are the raw materials of the toner, such as a fixing resin in which other charge control agents and other additives are uniformly dispersed, and mix thoroughly with a mixer such as a Henschel mixer or a super mixer, and then heat rolls and kneaders. Then, after melt-kneading using a hot melt kneader such as an extruder to sufficiently mix the materials, the mixture is cooled and solidified, and finely pulverized and classified to obtain toner mother particles.

As the pulverization method, a jet mill method in which toner is included in a high-speed air current, toner base particles collide with an impact plate and pulverized with the energy, an inter-particle collision method in which toner base particles collide with each other in the air current, Furthermore, a mechanical pulverization method in which toner mother particles are supplied and pulverized between a rotor rotated at high speed and a narrow gap can be used.
In the jet mill method and the interparticle method, the toner base particles are pulverized by the collision energy, so the shape of the pulverized toner base particles is relatively sharp. On the other hand, when the mechanical pulverization method is used, the toner base particles are pulverized while being rubbed between the gaps, and the surface of the toner base particles is easily spheroidized by the frictional heat generated at this time. In particular, in a toner with a target of reducing the particle size and fixing at a low temperature, the phenomenon that the toner melts and adheres to the collision plate at the time of pulverization as pointed out in JP-A-7-287413 does not occur. It is also possible to prevent a decrease in toner fluidity, which is a phenomenon peculiar when a diameter and a low molecular weight lubricant are contained.
The toner base particles can also be obtained by a so-called polymerization method in which a monomer, polymerized (fixing resin) is polymerized in the presence of a colorant, a charge control agent, a lubricant and the like. Further, toner base particles can be obtained by a microencapsulation method, an ester elongation method, a jet granulation method, and the like, and are not limited by the production method.

  The various external additives described above can be applied (coated) to the surface of the toner base particles obtained above. To coat the surface of the toner base with the external additive, for example, the toner base and the external additive are mixed and stirred using a mixer such as a Henschel mixer to obtain a toner with the additive added externally. Can do.

As described above, the image forming apparatus of the present invention includes at least an image carrier, a charging unit that charges the surface of the image carrier, and an exposure unit that exposes the charged image carrier surface to form an electrostatic latent image. Developing means for attaching toner to the developed electrostatic latent image, developing means for transferring the developed toner image to a recording medium, and contacting the image carrier after transfer with the image carrier in the forward or reverse direction. Cleaning means comprising a brush-like rotator for cleaning the toner on the image carrier while rotating in the direction, and the relative speed of the peripheral speed (A) of the image carrier and the peripheral speed (B) of the brush-like rotator The difference (| (A) − (B) |) is in the range of 1,500 to 15,000 mm / s, and the toner is the electrophotographic toner of the present invention.
Here, the electrophotographic toner of the present invention is poorly cleaned even if it is repeatedly used in an image forming apparatus (an apparatus having a brush-like rotating body for cleaning the toner on the image carrier) having a high process linear velocity. There is no occurrence of filming. For this reason, for example, even when the peripheral speed of the image carrier is 800 mm / s or higher, or even 1,700 mm / s or higher, high-quality images can be continuously output without problems.

  The developing device of the image forming apparatus of the present invention is selected according to the moving speed (rotational speed: peripheral speed) of the image carrier, but in the case of a high-speed printer or the like having a high peripheral speed of the image carrier, one development is performed. The development of the magnetic roll is not always sufficient, and a plurality of development magnetic rolls are used to develop the development area by increasing (longening) the development time. When a plurality of developing magnetic rolls are used, a higher developing ability is obtained compared to a single developing roll system, so that not only the response to high area image printing and the printing quality are improved, but also in the developer. The toner content can be reduced, and the rotation speed of the developing roll can be reduced, preventing the toner from being scattered and the carrier spent by the toner due to the reduction of the load on the developer being prevented. The lifetime can be further increased.

Furthermore, in the developing method using a plurality of developing rolls, the unidirectional development in which the developing roll rotates in the forward direction with the traveling peripheral speed of the electrostatic charge holding member has a high developing ability but tends to cause background fogging, Chipping of parts and magnetic brushes tend to appear. On the other hand, in unidirectional development in which the developing roll rotates in the direction opposite to the traveling direction of the image carrier, there is little background fogging but there is little fogging of the magnetic brush although there is a chip at the rear end of the image area, so a stable image can be obtained. Is obtained. However, since the reverse direction development has a small effective toner amount in contact with the image carrier, the development ability may be small.
In the case where the toner is developed using the center feed method in contrast to the above-mentioned method, since the mechanism that plays both roles in the forward and reverse developing rolls is provided, the disadvantages of both the above-described development methods are included. Both can be avoided. As a center feed type developing device, for example, the one described in Japanese Patent Publication No. Sho 62-45552 can be cited as a reference.
If the developing method of the image forming apparatus using the electrophotographic toner of the present invention is the center feed method, the image quality is further improved, and a stable toner adhesion amount is secured to both the character portion and the solid portion. Therefore, stable image formation without transfer defects can be performed with respect to changes in print density.

In general, in an image forming apparatus in which the rotational speed (peripheral speed) of an image carrier is high, a large amount of untransferred toner is recovered by cleaning, and more paper dust or the like remains on the image carrier. In addition, since many preprinted papers on which images have already been formed by offset printing or the like are used, a simple cleaning device such as a blade is insufficient.
In the present invention, a mechanism for cleaning the toner remaining on the image carrier by the brush-like rotator is used. As the material of the brush used, materials such as nylon, rayon, vinylon, and acrylic, and those containing conductive fibers in these materials are used, but are not limited to these materials.

The image forming method of the present invention includes at least a step of charging the image carrier with a charging unit, a step of forming an electrostatic latent image on the surface of the image carrier with an exposure unit, and a developing unit on the electrostatic latent image. A step of developing a toner image by attaching the toner to the recording medium, a step of transferring the developed toner image to a recording medium by a transfer unit, a step of fixing the transferred toner image by a fixing unit, and the transfer step An image forming method comprising a step of cleaning the toner on the image carrier by a cleaning unit comprising a brush-like rotator while contacting the image carrier and rotating in the forward or reverse direction with the image carrier. And
The relative speed difference (| (A)-(B) |) between the peripheral speed (A) of the image carrier and the peripheral speed (B) of the brush-like rotating body is in the range of 1,500 to 15,000 mm / s. In addition, the toner to be adhered is the above-described electrophotographic toner of the present invention.

The process cartridge of the present invention includes at least an image carrier, a charging unit for charging the surface of the image carrier, an exposure unit for exposing the charged image carrier surface to form an electrostatic latent image, and a formed static Developing means for developing the toner by attaching toner to the electrostatic latent image, transferring means for transferring the developed toner image to the recording medium, and contacting the image carrier after transfer in the forward or reverse direction with the image carrier A process cartridge that can be attached to and detached from an image forming apparatus main body integrated with at least one means selected from cleaning means consisting of a brush-like rotator that cleans the toner on the image carrier while rotating;
The relative speed difference (| (A)-(B) |) between the peripheral speed (A) of the image carrier and the peripheral speed (B) of the brush-like rotating body is in the range of 1,500 to 15,000 mm / s. In addition, the toner to be adhered is the above-described electrophotographic toner of the present invention.

FIG. 1 is a schematic diagram showing a configuration example of an image forming apparatus according to the present invention.
In FIG. 1, an image forming apparatus (1) includes a photoconductor (3) as an image carrier, a charging device (4) as a charging means for charging the surface of the photoconductor (3), and a surface of the photoconductor (3). And an exposure device (30) that is an exposure unit that forms an electrostatic latent image by exposing the toner, and a developing device (8) that is a developing unit that develops the toner by attaching toner to the formed electrostatic latent image. A transfer device (12), which is a transfer means for transferring the toner image to a recording medium [transfer material (10)], and contacted with the photoconductor (3) after transfer to the photoconductor (3) in the forward or reverse direction. A cleaning device (20), which is a cleaning means composed of a brush-like rotating body that cleans the toner on the photoreceptor (3) while rotating in the direction, is provided.
Relative speed difference (| (A)-(B) |) between the peripheral speed (A) of the photoreceptor (3) in the image forming apparatus (1) and the peripheral speed (B) of the brush-like rotating body of the cleaning device (20). Is controlled in the range of 1,500 to 15,000 mm / s. The peripheral speed (B) of the brush-like rotator is a plus sign for forward rotation with the photoreceptor (3), and a minus sign for reverse rotation with the photoreceptor (3). The toner used for the developing device (8) is the toner of the present invention.
The image forming apparatus is an example. In the present invention, the image forming apparatus includes at least an image carrier, a charging unit, an exposing unit, a developing unit, and a transferring unit, and the developing unit is filled with a plurality of toners having different development colors. The image forming apparatus may be a tandem type developing configuration that includes a developing unit and includes a plurality of image carriers corresponding to the plurality of developing units.

  EXAMPLES Hereinafter, although an Example and a comparative example are given and this invention is demonstrated further more concretely, this invention is not limited by this.

First, in the evaluation of Examples 1 to 9 and Comparative Examples 1 to 5, [Toner 1] was prepared according to Toner Preparation Example 1 below.
[Toner Preparation Example 1]
6 parts by weight of carbon black (MOGAL L manufactured by Cabot Corporation) and 31 parts by weight of polyester resin (1) [softening point T _1/2 : 108.5 ° C.], polyester resin (2) [softening point T _1/2 : 153. 9 ° C.] 60 parts by weight, 2 parts by weight of a non-molybdenum-based quaternary ammonium salt (Bontron P-51 manufactured by Orient Chemical Industries), 3 parts by weight of an azine charge control agent (Bontron N-04 manufactured by Orient Chemical Industries, Ltd.) Carnauba wax (Product name: Carnauba wax NO1 manufactured by Celerica NODA) 2.5 parts by weight of raw material is premixed with a super mixer, hot melt kneaded with a twin-screw kneader, cooled and pulverized. The pulverized product was classified using a dry air classifier to obtain a toner base material (toner base particles) having an average particle size of 8 μm. 0.4 parts by weight of hydrophobic silica (trade name: RA200HS, manufactured by Nippon Aerosil Co., Ltd.) is added to 100 parts by weight of the toner base particles, and the mixture is stirred with a Henschel mixer to adhere the hydrophobic silica to the surface of the toner base particles. [Toner 1].
The charge amount of [Toner 1] was 14.2 μc / g. Further, an endothermic peak of [Toner 1] measured with a differential scanning calorimeter was observed at 60 to 90 ° C.
The measurement of the softening point T _1/2 of the resin in the present invention is a value measured as follows.
Using a flow tester (Shimadzu Corporation, CFT-500D), 1 g of resin was heated at a rate of temperature increase of 6 ° C./min, a load of 1.96 MPa was applied by a plunger, and extruded from a nozzle with a diameter of 1 mm and a length of 10 mm. To do. The plunger drop amount of the flow tester is plotted against the temperature, and the temperature at which half of the sample flows out is taken as the softening temperature of the resin.

(Examples 1-9, Comparative Examples 1-5)
[Toner 1] prepared in Toner Preparation Example 1 above was mixed and stirred at a ratio of 4.5% by weight with respect to the silicone-coated magnetic carrier on the surface to prepare a two-component developer. Using this two-component developer, the peripheral speed (image carrier speed) of the image carrier (photoreceptor) and the peripheral speed of the brush-like rotary member (shown in Table 1) are measured by the apparatus configured as shown in FIG. (Fur brush speed) was set for each of Examples 1 to 9 and Comparative Examples 1 to 5, and the cleaning property and filming of the image carrier were evaluated. The evaluation results are shown in Table 1 below.
An Se-As photosensitive member was used as the image carrier (photosensitive member), and an image was formed at a charging potential of 700 V and a developing bias potential of 350 V. A brush-like rotating body (fur brush) is used for cleaning, and a developing magnetic roll for the developing machine rotates in the opposite direction to the developing magnetic roll that rotates in the forward and forward directions of the electrostatic charge holding member. An image was produced using a center feed type developing device having a roll with a developing gap (distance between the photosensitive member and the developing roll sleeve) of 0.8 mm.
The relative speed differences listed in Table 1 are obtained when the peripheral speed of the image bearing member (photosensitive member) is (A) and the peripheral speed (fur brush speed) of the brush-like rotating body is (B). The absolute value of the difference in peripheral speed (| (A)-(B) |) is obtained. Here, the peripheral speed (B) is + for the forward rotation with the image carrier (photosensitive member), and is-for the reverse rotation.
The fur brush speed shown in Table 1 indicates a value of-(B). For example, the value of 700 mm / s in Example 1 represents − (− 700), which indicates that the fur brush rotates in the reverse direction to the photoconductor. In the case of Comparative Example 2, the value of-(B) is -2500 mm / s and-(+ 2500), which indicates that the fur brush is rotating forward with the photosensitive member.
<Evaluation conditions>
Cleaning property: After printing an image having a printing density of 100%, the operation was stopped, and a mending tape was attached to the surface of the photoreceptor after passing through the cleaning portion, and the toner residue was confirmed.
Evaluation criteria: ○: good cleaning, x: poor cleaning Filming: After printing 100,000 pages of an image with a printing density of 4%, the surface of the photoconductor was magnified with a laser microscope to confirm the presence or absence of filming.
Evaluation criteria: ○: no filming, x: filming

  From the evaluation results shown in Table 1, in Examples 1 to 9 in which the relative speed difference between the image carrier speed and the fur brush speed is in the range of 1500 to 15000 mm / s, no cleaning failure or filming was observed. On the other hand, when the relative speed difference was slower than 1500 mm / s as in Comparative Examples 1 and 2, a cleaning failure occurred. Further, when the relative speed difference was faster than 15000 mm / s as in Comparative Examples 3 to 5, filming was confirmed on the image carrier.

  First, in carrying out the evaluation of Examples 10 to 18 and Comparative Examples 6 to 9, [Toner 2] to [Toner 5] and [Comparative toner] 1] to [Comparative toner 2] were prepared.

[Toner preparation example 2]
6 parts by weight of carbon black (MOGAL L manufactured by Cabot Corporation), 28 parts by weight of polyester resin (1) [softening point T _1/2 : 108.5 ° C.], polyester resin (2) [softening point T _1/2 : 153. 9 ° C.] 60 parts by weight, crystalline polyester [softening point T _1/2 : 120 ° C.] 5 parts by weight, non-molybdenum quaternary ammonium salt (Orient Chemical Industries Bontron P-51) 2 parts by weight, azine Charge control agent (Orient Chemical Industries, Ltd. Bontron N-04) 2 parts by weight, fatty acid amide (Kao Wax EB-FF, 3 parts by weight), rice wax (Cela Rica NODA, trade name: M-90) 2 A toner base material (toner base particles) having an average particle diameter of 7 μm was obtained by the same production method as in Example 1 using 5 parts by weight. 0.4 parts by weight of hydrophobic silica (manufactured by Nippon Aerosil Co., Ltd., trade name: RA200HS) and 0.05 parts by weight of calcium stearate (MC-2, manufactured by NOF Corporation) are added to 100 parts by weight of the obtained toner base particles. Then, the mixture was stirred with a Henschel mixer, and hydrophobic silica was adhered to the surface of the toner base particles to obtain [Toner 2].
The charge amount of [Toner 2] is shown in Example 10, Example 14, and Example 18 in Table 2 below. In addition, the endothermic peak measured with the differential scanning calorimeter of [Toner 2] was observed at 60 to 90 ° C., 90 to 120 ° C., and 120 to 140 ° C.

[Toner Preparation Example 3]
C. I. 2.3 parts by weight of a masterbatch containing 50% by weight of CI Pigment Red 48: 3 (manufactured by Dainichi Seika Kogyo Co., Ltd., trade name: Red NO.9), C.I. I. 6.8 parts by weight of a masterbatch containing 50% by weight of Pigment Yellow 180 (manufactured by Clariant Japan, trade name: TONER YELLOW HG), polyester resin (1) [softening point T _1/2 : 108.5 ° C] 29. 2 parts by weight, polyester resin (2) [softening point T _1/2 : 153.9 ° C.] 60 parts by weight, crystalline polyester [softening point T _1/2 : 120 ° C.] 5 parts by weight, non-molybdenum fourth Grade 1 ammonium salt (Clariant COPY CHARGE PSY) 1 part by weight, fatty acid amide (Kao Corporation Kao wax EB-FF) 2 parts by weight, rice wax (Cela Rica NODA, trade name: M-90) 1.5 parts by weight Parts, 1 part by weight of polypropylene wax (Biscol 550-P manufactured by Sanyo Chemical Industries), carnauba wax (manufactured by Celalica NODA, product name: In the same creation method as in Example 1 using a Luna carnauba wax NO1) 1 part by weight, to obtain toner base material having an average particle size of 5.8μm (toner mother particles). Hydrophobic silica (product name: RA200HS, manufactured by Nippon Aerosil Co., Ltd.) 0.6 part by weight and zinc stearate (MZ-2, manufactured by NOF Co., Ltd.) 0.03 part by weight with respect to 100 parts by weight of the obtained toner base particles. The mixture was added and stirred with a Henschel mixer, and hydrophobic silica was adhered to the surface of the toner base particles to obtain [Toner 3].
The charge amount of [Toner 3] is shown in Example 11, Example 15, and Example 19 in Table 2 below. The endothermic peaks of [Toner 3] measured with a differential scanning calorimeter were observed at 60 to 90 ° C., 90 to 120 ° C., and 120 to 140 ° C.

[Comparative toner preparation example 1]
6 parts by weight of carbon black (MOGAL L manufactured by Cabot Corporation), 28 parts by weight of polyester resin (1) [softening point T _1/2 : 108.5 ° C.], polyester resin (2) [softening point T _1/2 : 153. 9 ° C.] 60 parts by weight, crystalline polyester [softening point T _1/2 : 120 ° C.] 5 parts by weight, non-molybdenum-based quaternary ammonium salt (Clariant COPY CHARGE PSY) 2 parts by weight, charge control agent ( Hodogaya Chemical Co., Ltd. T-77) 1 part by weight, fatty acid amide (Kao Wax EB-FF manufactured by Kao Corporation) 3 parts by weight, carnauba wax (manufactured by Celarica NODA, trade name: carnauba wax NO1) 2.5 parts by weight The toner base material (toner base particles) having an average particle diameter of 7 μm was obtained by the same method as in Example 1. To 100 parts by weight of the obtained toner base particles, 0.5 part by weight of hydrophobic silica (product name: RA200HS, manufactured by Nippon Aerosil Co., Ltd.) is added and stirred with a Henschel mixer, and the surface of the toner base particles is hydrophobic silica. To make [Comparative Toner 1].
The charge amount of [Comparative Toner 1] is shown in Comparative Example 6, Comparative Example 8, and Comparative Example 10 in Table 2 below. In addition, the endothermic peak measured by the differential scanning calorimeter of [Comparative Toner 1] was observed at 60 to 90 ° C., 90 to 120 ° C., and 120 to 140 ° C.

[Toner Preparation Example 4]
6 parts by weight of carbon black (MOGAL L manufactured by Cabot Corporation), 28 parts by weight of polyester resin (1) [softening point T _1/2 : 108.5 ° C.], polyester resin (2) [softening point T _1/2 : 153. 9 ° C.] 60 parts by weight, non-molybdenum quaternary ammonium salt (Clariant COPY CHARGE PSY) 0.5 part by weight, charge control agent (Hodogaya Chemical Co., Ltd. T-77) 1.5 part by weight, carna A toner base material (toner base particle) having an average particle diameter of 7 μm was obtained by the same production method as in Example 1 using 2.5 parts by weight of Uba wax (trade name: Carnauba Wax NO1 manufactured by Celalica NODA). . 0.5 parts by weight of hydrophobic silica (manufactured by Nippon Aerosil Co., Ltd., trade name: R976) and 0.05 parts by weight of zinc stearate (MZ-2 manufactured by NOF Corporation) are added to 100 parts by weight of the obtained toner base particles. The mixture was added and stirred with a Henschel mixer, and hydrophobic silica was adhered to the surface of the toner base particles to obtain [Toner 4].
The charge amount of [Toner 4] is shown in Example 12, Example 16, and Example 20 in Table 2 below. The endothermic peak of [Toner 4] measured with a differential scanning calorimeter was observed at 60 to 90 ° C.

[Toner Preparation Example 5]
C. I. 2.3 parts by weight of a masterbatch containing 50% by weight of CI Pigment Red 48: 3 (manufactured by Dainichi Seika Kogyo Co., Ltd., trade name: Red NO.9), C.I. I. 6.8 parts by weight of a masterbatch containing 50% by weight of Pigment Yellow 180 (manufactured by Clariant Japan, trade name: TONER YELLOW HG), polyester resin (1) [softening point T _1/2 : 108.5 ° C.] 2 parts by weight, polyester resin (2) [softening point T _1/2 : 153.9 ° C.] 60 parts by weight, non-molybdenum-based quaternary ammonium salt (Orient Chemical Industries Bontron P-51) 0.2 parts by weight , 1 part by weight of a boron-based charge control agent (LR-147 manufactured by Nippon Carlit Co., Ltd.), 2 parts by weight of fatty acid amide (Kao wax EB-FF manufactured by Kao Corporation), rice wax (trade name: M-90 manufactured by Celarica NODA) 1.5 parts by weight, polypropylene wax (Biscol 550-P manufactured by Sanyo Chemical Industries, Ltd.) 1 part by weight, carnauba wax (manufactured by Celalica NODA, Name: In the same creation method as in Example 1 using carnauba wax NO1) 1 part by weight, to obtain toner base material having an average particle size of 6.8μm (toner mother particles). Hydrophobic silica (manufactured by Nippon Aerosil Co., Ltd., trade name: R976) 0.6 part by weight and zinc stearate (manufactured by NOF Co., Ltd., MZ-2) 0.03 part by weight with respect to 100 parts by weight of the obtained toner base particles. The mixture was added and stirred with a Henschel mixer, and hydrophobic silica was adhered to the surface of the toner base particles to obtain [Toner 5].
The charge amount of [Toner 5] is shown in Example 13, Example 17, and Example 21 in Table 2 below. The endothermic peak of [Toner 5] measured with a differential scanning calorimeter was observed at 60 to 90 ° C. and 120 to 140 ° C.

[Comparative toner preparation example 2]
6 parts by weight of carbon black (MOGAL L manufactured by Cabot Corporation) and 31 parts by weight of polyester resin (1) [softening point T _1/2 : 108.5 ° C.], polyester resin (2) [softening point T _1/2 : 153. 9 ° C.] 60 parts by weight, 4 parts by weight of an azine charge control agent (Bontron N-04 manufactured by Orient Chemical Industry Co., Ltd.), 2.5 parts by weight of carnauba wax (manufactured by Celalica NODA, trade name: carnauba wax NO1) Toner base material with an average particle size of 6.4 μm is premixed with a supermixer, heat melt kneaded with a twin-screw kneader, cooled and pulverized, and the pulverized material is classified with a dry air classifier (Toner mother particles) was obtained. 0.6 parts by weight of hydrophobic silica (trade name: RA200HS, manufactured by Nippon Aerosil Co., Ltd.) is added to 100 parts by weight of the toner base particles, and the mixture is stirred with a Henschel mixer to adhere the hydrophobic silica to the surface of the toner base particles. Thus, [Comparative Toner 2] was obtained.
The charge amount of [Comparative Toner 2] is shown in Comparative Example 7, Comparative Example 9, and Comparative Example 11 in Table 2 below. In addition, the endothermic peak measured by the differential scanning calorimeter of [Comparative Toner 2] was observed at 60 to 90 ° C.

(Examples 10 to 21, Comparative Examples 6 to 11)
Next, using [Toner 2] to [Toner 5] and [Comparative Toner 1] to [Comparative Toner 2] prepared in Toner Preparation Examples 2 to 5 and Comparative Toner Preparation Examples 1 and 2, respectively, the surface is coated with silicone. A two-component developer was prepared by mixing and stirring at a ratio of 4.5% by weight to the magnetic carrier. Using this two-component developer, the peripheral speed (image carrier speed) of the image carrier (photoconductor) and the peripheral speed (fur brush speed) of the brush-like rotating body are measured by the apparatus having the configuration shown in FIG. The relative speed difference was set as shown in Table 2 below, and the cleaning property, filming of the image bearing member, and fogging were evaluated.
In the evaluation using [Toner 2], [Toner 3], [Comparative Toner 1], and [Comparative Toner 2], a Se-As photoconductor is used as the photoconductor, and [Toner 4] and [Toner 5] are used. In the evaluation using an OPC photoreceptor, an image was formed with a difference between the charging potential and the developing bias of 350 V. As in Example 1, a brush-like rotator (fur brush) was used for cleaning. The developing machine uses a developing device of a center feed type having a developing magnetic roll in which the developing magnetic roll rotates in the forward and forward directions of the electrostatic charge holding member and a developing magnetic roll in the reverse direction. The distance between the photosensitive member and the developing roll sleeve was 0.8 mm to form an image.
The relative speed difference between the peripheral speed of the image carrier (photoreceptor) and the peripheral speed of the fur brush in each evaluation shown in Table 2 below is the same as described in the first embodiment.
<Evaluation conditions>
Cleaning property: After printing an image having a printing density of 100%, the operation was stopped, and a mending tape was attached to the surface of the photoreceptor after passing through the cleaning portion, and the toner residue was confirmed.
Evaluation criteria: ○: good cleaning, x: poor cleaning Filming: After printing 100,000 pages of an image with a printing density of 4%, the surface of the photoconductor was magnified with a laser microscope to confirm the presence or absence of filming.
Evaluation criteria: ○: no filming, x: filming Fog: A phenomenon in which toner is on the background of the image was visually confirmed.
Evaluation criteria: ○ is no fogging, × is fogging

As shown in Table 2, in Examples 10 to 21, no cleaning failure or filming occurred, no fogging occurred, and good results were obtained in any evaluation.
On the other hand, in Comparative Examples 6, 8, and 10 in which the charge amount was less than 4 μc / g, cleaning failure and filming did not occur, but fogging in which toner was placed on the background of the image occurred. Further, in Comparative Examples 7 and 9 (the relative speed difference was 9700 mm / s) where the charge amount was larger than 25 μc / g, a cleaning failure occurred, and a toner residue was confirmed on the mending tape. In Comparative Examples 7, 9, and 11, filming also occurred after printing 100,000 pages, and in Comparative Example 11 (relative speed difference was 14000 mm / s), the image of the filmed portion was lost and whitened.

  That is, the electrophotographic toner (including a two-component developer) of the present invention is excellent in cleaning properties and non-filming properties, and can form high-quality images without fogging even in repeated high-speed printing. If such an electrophotographic toner is used in, for example, an image forming apparatus such as a copying machine, a laser printer or a normal facsimile, a process cartridge or an image forming method, cleaning defects and film are not detected even if it is repeatedly used at a high process linear speed. It is possible to continuously output a stable high-quality image without any occurrence of ming.

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 2 Fixing apparatus 13 Preheating board 14 Heating roller 15 Pressure roller 21 Fixing roller 3 Photoconductor 4 Charging apparatus 8 Developing apparatus 81 Developing unit 8a Developer carrier 82 Toner supply chamber 9 Paper hopper 10 Transfer material 11 Paper Transport tractor 12 Transfer device 16 Paper feed roller 17 Swing fin 19 Stacker table 20 Cleaning device 24 Buffer plate 30 Exposure device 5 Rotating polygon mirror 6 Light source 7 fθ lens T Transfer position

JP 2007-72333 A JP-A-7-287413 JP-A-7-261621 JP 2001-188452 A

Claims (13)

At least an image carrier and a brush-like rotator for cleaning the toner on the image carrier while rotating in the forward or reverse direction with the image carrier in contact with the image carrier, An image forming apparatus in which the relative speed difference (| (A) − (B) |) between the speed (A) and the peripheral speed (B) of the brush-like rotating body is in the range of 1,500 to 15,000 mm / s. An electrophotographic toner used,
The toner contains a charge control agent containing at least a non-molybdenum-based quaternary ammonium salt and a fixing resin, and the toner has a weight average particle diameter in the range of 2 to 10 μm, and an absolute value of the charge amount is 4 An electrophotographic toner characterized by being in the range of ˜25 μc / g.   The electrophotographic toner according to claim 1, wherein the electrophotographic toner contains a lubricant.   The electrophotographic toner according to claim 2, wherein the lubricant is contained both in the toner and in the toner surface layer.   4. The electrophotographic toner according to claim 3, wherein the lubricant contained in the toner contains a fatty acid amide lubricant and a fatty acid lubricant.   5. The electrophotographic image according to claim 3, wherein the lubricant contained in the toner contains a fatty acid amide-based lubricant, and the lubricant contained in the toner surface layer portion contains a fatty acid metal salt lubricant. Toner.   The electrophotographic toner has at least one endothermic peak measured by a differential scanning calorimeter in any of the temperature ranges of 60 to 90 ° C., 90 to 120 ° C., and 120 to 140 ° C. The toner for electrophotography according to any one of claims 1 to 5.   The electrophotographic toner according to claim 1, wherein the electrophotographic toner is a color toner and / or a transparent toner.   The electrophotographic toner according to claim 1, wherein the electrophotographic toner is used as a two-component developer together with a carrier.   The electrophotographic toner according to claim 1, wherein a peripheral speed of the image carrier is 800 mm / s or more.   The electrophotographic toner according to claim 1, wherein a peripheral speed of the image carrier is 1,700 mm / s or more. At least an image carrier, a charging unit that charges the surface of the image carrier, an exposure unit that exposes the charged image carrier surface to form an electrostatic latent image, and a toner that adheres to the formed electrostatic latent image for development Developing means for transferring, a transfer means for transferring the developed toner image to a recording medium, and a toner on the image carrier while contacting the image carrier after the transfer and rotating in the forward or reverse direction with the image carrier. A cleaning means comprising a brush-like rotating body to be cleaned, and a relative speed difference (| (A)-(B) |) between the peripheral speed (A) of the image carrier and the peripheral speed (B) of the brush-like rotating body; Is an image forming apparatus in a range of 1,500 to 15,000 mm / s,
The image forming apparatus according to claim 1, wherein the toner is an electrophotographic toner according to claim 1. At least an image carrier, a charging unit for charging the surface of the image carrier, an exposure unit for exposing the charged image carrier surface to form an electrostatic latent image, and attaching toner to the formed electrostatic latent image Development means for developing, transfer means for transferring the developed toner image to a recording medium, and toner on the image carrier while contacting the image carrier after transfer and rotating in the forward or reverse direction with the image carrier A process cartridge that can be attached to and detached from the image forming apparatus main body integrated with at least one means selected from cleaning means comprising a brush-like rotating body for cleaning
The relative speed difference (| (A)-(B) |) between the peripheral speed (A) of the image carrier and the peripheral speed (B) of the brush-like rotating body is in the range of 1,500 to 15,000 mm / s. A process cartridge, wherein the toner to be attached is the electrophotographic toner according to claim 1. At least a step of charging the image carrier with a charging unit, a step of forming an electrostatic latent image on the surface of the image carrier with an exposure unit, and a toner attached to the electrostatic latent image with a developing unit to develop as a toner image A step of transferring the developed toner image to a recording medium by a transfer unit, a step of fixing the transferred toner image by a fixing unit, and contacting the image carrier after the transfer step. An image forming method comprising a step of cleaning the toner on the image carrier by a cleaning unit comprising a brush-like rotator while rotating in the forward or reverse direction with the image carrier,
The relative speed difference (| (A)-(B) |) between the peripheral speed (A) of the image carrier and the peripheral speed (B) of the brush-like rotating body is in the range of 1,500 to 15,000 mm / s. An image forming method, wherein the toner to be adhered is the electrophotographic toner according to claim 1.

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