JP4498015B2 - Method for evaluating surface characteristics of developer carrier - Google Patents

Description

  The present invention relates to a developing device that performs development using a developer, and more particularly to a developing device used in an image forming apparatus such as a copying machine or a printer using an electrophotographic recording system.

  Conventionally, as a developing device applied to an image forming apparatus using a magnetic developer, there is one in which a hopper chamber and a developing chamber are arranged (see, for example, Patent Document 1 and Patent Document 2).

  A conventional example will be described with reference to FIG. FIG. 6 is a schematic cross-sectional view of a batch supply type developing device.

  The developer carrying member 101 rotates in the direction of the arrow, and a developer layer is formed on the surface of the developer carrying member 111 by the developer regulating member 111. The developer is conveyed and developed at a position facing the image carrying member 102. ing. A developing chamber 103 is disposed adjacent to the developer carrying member 101, and the developer is stirred by a developing chamber stirring member 104 that conveys the developer to the developer carrying member 101 while stirring the developer along the longitudinal direction of the developer carrying member 101. A developer is supplied to the carrier 101. A hopper chamber 105 is adjacent to the developing chamber 103 through a partition wall 109. The hopper chamber 105 is provided with a rotating stirring member 106 that conveys the developer toward the developing chamber 103 while stirring the developer, and the supply amount is adjusted by the opening 110. In addition, an opening 112 that can be opened and closed for replenishing the developer is provided in the upper part of the developing device.

  The developing chamber agitating member 104 and the rotating agitating member 106 rotate at a constant ratio with respect to the rotational speed of the developer carrier 101 to agitate and convey the developer.

  When the developer is replenished, the replenished developer is agitated by the rotary agitating member 106 and simultaneously conveyed toward the developing chamber 103 through the opening 110.

  Further, as a method for optimizing the amount of developer supplied to the developer carrier, there is a method in which a developer carrier is disposed in the upper opening of the developing device (see, for example, Patent Document 3 and Patent Document 4). Briefly described with reference to FIG. 7, a developer regulating member 111 that is disposed opposite to the developer carrying member 101 and regulates the amount of the developer on the developer carrying member 101 and has magnetism, and after passing through the developing region. A separation member that peels off the developer on the developer carrier 101, a partition member that partitions the development chamber 103 including the developer regulating member 111 and the second region including the separation member, and a development chamber On the partition member, a staying member that temporarily retains the developer conveyed from the rotary stirring member 106 in front of the developer carrying member 101 is erected with the upper space remaining, and the staying member and the developer carrying member are left standing. 101 is formed as a developer non-retention area.

  The magnetic developer is required to be excellent in various properties such as low-temperature fixability and high-temperature offset resistance, and in order to improve these points, a wax is contained in the magnetic developer (for example, (See Patent Document 5 and Patent Document 6).

  As a method for preventing sleeve contamination / fusion, there is a method for defining a dynamic friction coefficient of a developer carrying member (see, for example, Patent Document 7).

  Further, there is one that measures the dynamic friction coefficient of the developer carrying member with respect to the developer (see, for example, Patent Document 8 and Patent Document 9).

JP 2001-147777 A JP 2002-196574 A Japanese Patent Laid-Open No. 11-038761 Japanese Patent Laid-Open No. 11-044991 Japanese Patent Laid-Open No. 2000-242040 JP 2003-084501 A JP 2002-099141 A JP-A-6-214452 JP-A-7-114269

  However, in the conventional example shown in FIG. 6, the developer accumulated on the back side of the developer regulating member 111 is scraped by the developing chamber stirring member 104, but the developer accumulates in a portion where the developing chamber stirring member 104 does not reach. In this case, the developer packing occurs in this portion, and problems such as deterioration of the developer, poor coating of the developer on the developer carrying member, and resulting low development density occur. Further, since the developer is supplied to the developer carrier 101, the developing chamber 103 is also provided in addition to the hopper chamber 105. Therefore, it is difficult to save the space of the developing device, and the image forming apparatus cannot be made compact. Further, since the developing chamber stirring member 104 must be provided in addition to the rotating stirring member 106, it is difficult to reduce the cost.

  In the conventional example shown in FIG. 8, since the developing chamber 105 is also arranged in addition to the hopper chamber 103, and further, a partition member and a peeling member are also installed, it is difficult to save space and reduce costs.

  On the other hand, in the conventional example in which a release agent is contained in the magnetic developer, there is no problem in the conventional developing device as shown in FIG. 6, but depending on the developing device, the flowability of the developer deteriorates. It tends to be easy. In addition, due to the long-term use of the developing device, the developer is caught on the fine uneven valleys on the surface of the developer carrying member and becomes contaminated with the sleeve, and further, fusion occurs due to pressing or the like at the time of regulating the developer layer thickness. There is.

  In particular, in response to the recent demands for higher image quality and lower power consumption of copiers, the developer can be used over a long period of time as the particle size and the softening point of the magnetic developer are reduced. There is a stronger tendency of fusing to the irregularities on the surface of the carrier and leading to contamination.

  When the developer fusing occurs on the surface of the developer carrying member, first, the transport amount of the developer to the developing area is lowered, and the image density is likely to be lowered. Conventionally, an alternating electric field (development bias) is often applied to the developer carrier during development in order to perform good development. However, if toner fusion occurs on the surface of the developer carrier, the development is performed. As a result, a high resistance layer is formed on the surface of the agent carrier, and a desired electric field is not formed in the development area between the developer carrier and the image carrier during development. The effect cannot be obtained, and the image density tends to decrease or image defects such as white spots are likely to occur.

  In the case of Patent Document 7 that defines the dynamic friction coefficient in order to improve the above-mentioned contamination and fusion, the dynamic friction coefficient is due to contact with the stainless steel thin plate, so that a sufficient effect may not be obtained depending on the developer and the developing device. is there. Further, it is not always possible to cope with the fusion of the developer to the resin coating layer.

  Further, since the methods of Patent Document 8 and Patent Document 9 for directly measuring the coefficient of dynamic friction of the developer carrying member with respect to the developer relate to a developing device using a non-magnetic one-component developer, a magnetic one-component developer is used. In the case of a developing device, a sufficient effect may not be obtained. In addition, since the dynamic friction coefficient method of Patent Document 9 uses a compacted developer as a measuring element, measurement is performed in a state where the shape of the developer is deformed. Therefore, in the calculated dynamic friction coefficient, development is performed. Depending on the agent and the developing device, a sufficient correlation may not be obtained.

The present invention does not cause sleeve contamination or fusion even in long-term durability, and is of a high quality that does not cause image quality deterioration such as image density reduction, ghost, blotch, solid white fog, not only at normal temperature and humidity, but also at normal temperature and low humidity or high temperature and high humidity. An object of the present invention is to provide a method for evaluating the surface characteristics of a developer carrying member that gives an image.

The method for evaluating the surface characteristics of the developer carrying member according to the present invention is as follows.
Magnetic developer,
A container of the magnetic developer;
A developer carrier having a substrate and a resin coating layer formed on the surface of the substrate, which is disposed in the opening of the container and rotates to supply the magnetic developer in the container to the image carrier; ,
A rotating stirring member disposed in the container for stirring the magnetic developer and supplying the magnetic developer to the developer carrying member;
A magnetic developer replenishment detecting means disposed in the container,
In the developing device, the lower end of the developer carrying member is located above the rotation center axis of the rotary stirring member, and the upper end of the replenishment detection means is located below the rotation center axis of the rotation stirring member. A method for evaluating the surface characteristics of a developer carrier used,
A developer fixing piece for measuring a dynamic friction coefficient, in which a solid black unfixed image formed on plain paper for a copying machine with the magnetic developer was fixed without pressure on the flat surface of the test piece of the resin coating layer, was attached. It has a step of contacting a 30 mm flat indenter with a load that maintains the shape of the magnetic developer, and sliding it at 6000 mm / min to measure the dynamic friction coefficient.

According to the present invention, an appropriate amount of developer can be supplied to the developer carrying member without providing a plurality of stirring members in the developing device. Accordingly, since the toner stirring chamber and the developing chamber can be integrated, the developing device can be simplified and made compact. As a result, the cost and space saving of the image forming apparatus using the developing device of the present invention can be achieved. Further, it is possible to provide a developing device that realizes an image forming apparatus that is excellent in low-temperature fixability and high-temperature offset resistance in a one-component magnetic developer and excellent in durability of a large number of sheets under normal temperature and low humidity or high temperature and high humidity. I can do it.

  Furthermore, it is possible to provide a developing device that does not contaminate or fuse the sleeve even during long-term durability. In addition to room temperature and normal humidity, high-quality images can be obtained over a long period of time without causing image quality defects such as image density reduction, ghost, blotch, and fog at room temperature, low humidity, and high temperature and high humidity. That is, a stable high-quality image can be provided.

In addition, according to the present invention, since the degree of toner aggregation does not increase, toner coating unevenness on the developer carrying member is eliminated, and as a result, it is possible to provide a developing device that does not generate solid black density unevenness even in the latter half of durability.

  Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in the following embodiments should be appropriately changed according to the configuration of the apparatus to which the present invention is applied and various conditions. As long as there is no specific description, it is not the meaning which limits the scope of the present invention only to them.

  First, a developing device to which the present invention is applied will be described in detail with reference to FIG. FIG. 1 is a sectional view of the developing device of the present invention.

  As shown in FIG. 1, the developer carrier 1 is rotated in the direction of the arrow, and a developer layer is formed on the surface of the developer regulating member 11 to convey the developer. Development is performed at the opposite position.

  The developer carrier 1 is adjacent to the hopper chamber 5. The hopper chamber 5 is provided with a rotating stirring member 6 that conveys the developer toward the developer carrier 1 while stirring the developer, and supplies the developer to the developer carrier 1. In addition, an opening 12 that can be opened and closed for supplying a developer is provided in the upper part of the developing device.

  In the hopper chamber 5, a developer replenishment detecting member 13 is arranged so that the position about 15 mm from the bottom of the developing container, on the other side of the hopper chamber wall, is the center.

  The developer replenishment detection member 13 is composed of a piezoelectric element, which detects the presence or absence of the developer in a portion immediately inside the developer replenishment detection member 13 in the hopper chamber 5 and develops the detection signal. This is communicated to the agent supply determination device 14. The developer replenishment determination device 14 continuously receives a signal from the developer replenishment detection member 13, and determines that there is no developer when it receives a no-developer signal from the developer replenishment detection member 13. The sensor surface of the developer replenishment detection member 13 has a circular shape with a diameter of 10 mm, and the developer is present in all regions on the sensor surface since no developer is present in the region of 1/2 or more on the sensor surface. A signal indicating that there is no developer is output in one of the states before the start. That is, the output of the signal indicating no developer is started while the developer is reduced to the line a in FIG. 1 while the developer is reduced to the line b.

  In the developing device of the present embodiment, the target remaining developer amount when determining the absence of developer is 200 g.

  In the present embodiment, the height d of the lower end of the developer carrier 1 is about 50 mm from the bottom of the developing container. The height g of the rotation center axis of the rotary stirring member 6 is about 40 mm from the bottom of the developing container. The height t of the powder surface of the developer in the hopper chamber 5 is at a position of about 45 mm from the bottom of the developing container at the maximum. The height s of the upper end of the developer supply detection member 13 is about 20 mm from the bottom of the developing container. Therefore, the height t of the powder surface of the developer is between about 20 mm and 45 mm from the bottom of the developing container.

  The present invention is not limited to the above numerical values. For example, the lower end of the developer carrier 1 may be at a position higher than the rotation center axis of the rotating stirring member 6, and the upper end of the developer supply detection member 13 is higher than the rotation center axis of the rotating stirring member 6. Any lower position is acceptable. Furthermore, the powder surface of the developer in the hopper chamber 5 may be at a position lower than the lower end of the developer carrier 1.

  The developer replenished from the opening 12 at the top of the developer container enters the hopper chamber 5, and the developer is conveyed to the developer carrier 1 by the rotating stirring member 6. At this time, since the rotation center axis height g of the rotary stirring member 6 is located below the lower end of the developer carrier 1, the developer supply to the developer carrier 1 is pumped up from below. , It will not be oversupplied, but will be supplied in appropriate amounts. Therefore, as in the conventional developing apparatus as shown in FIG. 6, in order to optimize the developer supply amount, an extra space is provided in which a developing chamber 103 is provided in addition to the hopper chamber 105 and the supply amount is adjusted by the opening 110 thereof. There is no need to provide. In addition, since the upper end of the developer replenishment detecting means is positioned below the rotation center axis height g of the rotating stirring member 6, the developer powder signal is output on the rotating stirring member 6 with no developer output. It becomes when it becomes below the rotation center axis height g. Therefore, the developer powder surface does not become higher than the rotation center axis height g of the rotary stirring member 6, so that the developer can be transported to the developer carrier 1 from a sufficiently stirred state in the stirring chamber. become.

  Further, as shown in FIG. 1, the developer on the back side of the developer regulating member 11 in the present embodiment moves upward along the developer regulating member and eventually falls below the hopper chamber 5 due to the influence of gravity. Good prevention of developer packing can be achieved. Therefore, unlike the conventional developing device, it is not necessary to install the developing chamber stirring member 104 and scrape off the developer staying behind the developer regulating member 11. At this time, the angle θb formed with the horizontal direction of the developer regulating member 11 in the developing device is preferably 45 ° or less in order to prevent good packing. When the angle exceeds 45 °, the developer on the back side of the developer regulating member 11 is hardly affected by gravity and does not fall below the hopper chamber 5 but stays in the vicinity of the developer carrying member on the back side of the developer regulating member 11 and eventually develops. Excessive agent causes strong packing, and toner deterioration, fading, and low end density tend to occur.

  In the present embodiment, a ferromagnetic metal material is used as the developer regulating member 11, but a non-magnetic material can also be used.

  When the developing device of the present invention as shown in FIG. 1 is used, the developer is not provided, but the developer is pumped from the lower side of the hopper chamber 5 by the rotating agitating member 6 to the developer carrier 1 directly. Therefore, the developer is pressed against the developer carrier 1. Therefore, the developer is stressed between the rotary stirring member 6 and the developer carrier 1, and the developer is fixed to the surface of the developer carrier 1 for a long period of time, and a phenomenon such as sleeve contamination and fusion is likely to occur. For this purpose, it is necessary to optimize the dynamic friction coefficient with respect to the developer on the surface of the developer carrier 1.

  As a result of detailed studies, the present inventors have found that when the developer and the developer-carrying resin coating layer surface are measured for the dynamic friction coefficient in a manner close to the situation in the developing apparatus, sleeve contamination and fusion occur. It has been found that a preferable range can be found in which good image characteristics can be obtained. For this purpose, first, a measuring element is prepared by attaching a developer on which a solid black unfixed image on paper is fixed with no pressure to a 30 mm flat indenter for HEIDON. A dynamic friction coefficient is measured when the developer carrying resin coating layer surface is moved with a predetermined load. By doing so, it is possible to measure the dynamic friction coefficient in a state where the developer shape is maintained, so that the state of the developer and the developer carrier in the actual developing device can be modeled. At this time, when the dynamic friction coefficient at a load of 0.49 N is 0.20 or more and 2.00 or less and the load at a load of 0.98 N is 0.15 or more and 1.20 or less, the image characteristics are most preferable. It was revealed. When the coefficient of dynamic friction at a load of 0.49 N exceeds 2.00, or when the load at a load of 0.98 N exceeds 1.20, the developer is likely to be deposited on the surface of the developer carrier. It has been found that wearing tends to occur. Further, when the load is 0.49N or less than 0.20, or 0.99N or less than 0.15, the developer becomes difficult to be carried on the surface of the developer carrying member, and the image density decreases during the durability. It was found that the image quality is likely to deteriorate. The mechanism in which the correlation between the dynamic friction coefficient when the load in the measurement of the dynamic friction coefficient of the present invention is 0.49 N to 0.98 N and the image characteristics is not clear, but the load range applied to the measuring element is This is equivalent to the force exerted by the developer behind the developer regulating member of the developing device on the surface of the developer carrying member, and as a result, this measurement method specifies the movement of the developer on the surface of the developer carrying member in the developing device of the present invention. It seems to have become.

Next, a method for producing a probe used for the main measurement will be described. At developer a black-and-white copying machine used in this example (e.g., Canon GP405), on normal copying machine plain paper (75g / m ^2), solid black (8 g / m ² the toner developing amount of paper (Set to ˜9 g / m ² )). By performing pressureless fixing for 30 minutes in a 150 ° C. atmosphere, a developer fixing piece for measuring a dynamic friction coefficient in which the shape of the developer is maintained is obtained. This is cut out to a predetermined size and attached to a 30 mm flat indenter for HEIDON.

Next, as shown in FIG. 3, with a HEIDON surface property measuring instrument 14DR · ANL, Ru is brought into contact with the developer fixing piece 309 attached to 30mm flat indenter to the test piece 310 of the developer carrying member resin coating layer. The load cell 308 detects the resistance value when this is slid with the moving table 312 at 6000 mm / min. When the weight 311 is 50 g (0.49 N) and 100 g (0.98 N), the dynamic friction coefficient is obtained by (detection value) / (weight of mass).

  Next, the developer carrier used in the present invention will be described.

  The developer carrier used in the present invention has at least a substrate and a resin coating layer formed on the surface of the substrate.

  The shape and material of the substrate are not particularly limited as long as the resin coating layer can be formed on the surface. Examples of the shape of the base include a cylindrical member, a columnar member, and a belt-like member. As the substrate, for example, when a non-contact developing method is used as an electrostatic latent image carrier (photosensitive drum) as a developing method, a metal cylindrical member is preferably used, and specifically, a metal cylindrical tube is used. Preferably used. As the metal cylindrical tube, nonmagnetic materials such as stainless steel, aluminum and alloys thereof are preferably used.

  As the binder resin used for the resin coating layer, a known resin exhibiting an appropriate film forming property when the layer is formed can be used. For example, thermoplastic resins such as styrene resin, vinyl resin, polyethersulfone resin, polycarbonate resin, polyphenylene oxide resin, polyamide resin, fluorine resin, fiber resin, acrylic resin; epoxy resin, polyester resin, alkyd resin Thermal or photo-curable resins such as phenol resin, melamine resin, polyurethane resin, urea resin, silicone resin, polyimide resin, etc. can be used. Among them, those with releasability such as silicone resin and fluororesin, or excellent mechanical properties such as polyethersulfone, polycarbonate, polyphenylene oxide, polyamide, phenol, polyester, polyurethane, styrene resin, acrylic resin Is more preferable.

In the present invention, the resin coating layer formed on the developer carrying member is fixed on the developer carrying member due to charge-up, or the developer carrying member generated when the magnetic developer is charged up. In order to prevent poor charging from the surface of the magnetic developer to the magnetic developer, it is desirable to be conductive. In addition, the volume resistance value of the resin coating layer is preferably 10 ⁴ Ω · cm or less, more preferably 10 ³ Ω · cm or less. When the volume resistance value of the resin coating layer exceeds 10 ⁴ Ω · cm, a poor charge application to the magnetic developer is likely to occur, and as a result, blotch is likely to occur.

  The resin coating layer has a volume resistance of 7 μm to 20 μm formed on a 100 μm thick PET sheet, and a four-terminal probe using a resistivity meter Loresta AP or Hiresta IP (both manufactured by Mitsubishi Chemical). It can measure by using. The measurement environment is 20 ° C. to 25 ° C. and 50% RH to 60% RH.

  In the present invention, in order to adjust the resistance value of the coating layer to the above-mentioned value, it is preferable to contain the following conductive material in the coating layer. Examples of the conductive material used at this time include metal powders such as aluminum, copper, nickel, and silver, metal oxides such as antimony oxide, indium oxide, and tin oxide, carbon fiber, carbon black, and graphite. Examples include carbon materials. In the present invention, among these, carbon black, in particular conductive amorphous carbon, is particularly excellent in electrical conductivity, and it can be filled with a polymer material to impart conductivity, or only by controlling the amount of addition. Since arbitrary conductivity can be obtained to some extent, it is preferably used. Moreover, it is preferable to make the addition amount of these electroconductive substances suitable in this invention into the range of 1 mass part-100 mass parts with respect to 100 mass parts of binder resin.

  Furthermore, in the present invention, a solid lubricant can be mixed in the coating layer in order to further reduce the adhesion of the developer to the surface of the developer carrying member. Examples of the solid lubricant that can be used in this case include molybdenum disulfide, boron nitride, graphite, graphite fluoride, silver-selenium niobium, calcium chloride-graphite, and talc. Of these, graphite is preferably used in the present invention. Moreover, it is preferable to make the addition amount of these solid lubricants suitable by this invention into the range of 1 mass part-100 mass parts with respect to 100 mass parts of binder resin. Furthermore, it turned out that it is more preferable that it is the range of 30 mass parts-100 mass parts. When the amount is less than 30 parts by mass, the coefficient of dynamic friction with the developer in the present invention exceeds 2.00 when the load is 0.49 N, or exceeds 1.20 when the load is 0.98 N. It has been found that fusion is likely to occur. Further, when it exceeds 100 parts by mass, the load at 0.49 N load is less than 0.20, or the load at 0.98 N load is less than 0.15, and it becomes difficult for the developer to be carried on the surface of the developer carrying member. It was found that image quality deterioration such as low image density tends to occur.

  Further, in the present invention, a uniform surface roughness is maintained on the surface of the coating layer of the developer carrying member, and at the same time, a certain degree of protrusion is provided on the surface of the coating layer, thereby suppressing a load caused by contact between the surface of the coating layer and the toner. In order to make it difficult for toner fusion and toner contamination to occur, spherical particles can be added.

  As the particle size of the spherical particles, the volume average particle size is 3 μm to 30 μm, preferably 5 μm to 25 μm, more preferably 10 μm to 25 μm. When the volume average particle diameter of the spherical particles is less than 3 μm, the effect of imparting uniform and sufficient roughness to the surface is poor, toner charge-up due to wear of the coating layer, toner contamination and toner fusion occur, ghost deterioration, Causes image density reduction. When the volume average particle size exceeds 30 μm, the surface roughness of the coating layer becomes too large, and it becomes difficult to sufficiently charge the toner, and the mechanical strength of the coating layer is lowered. The spherical shape in the present invention preferably has a ratio of major axis / minor axis of particles of 1.0 to 1.5 (preferably 1.0 to 1.2). In particular, spherical particles are preferable.

  Furthermore, the difference in volume average particle size between the solid lubricant used and the spherical particles is preferably within 2.5 μm, more preferably within 1.0 μm. When the volume average particle size difference exceeds 2.5 μm, the unevenness of the resin coating layer becomes uneven, and the range of the dynamic friction coefficient with the developer of the present invention cannot be realized.

  As the spherical particles used in the present invention, known spherical particles can be used. For example, there are spherical resin particles, spherical metal oxide particles, spherical carbonized particles, and the like, which are appropriately used according to the developability of the toner and the development system.

  As the spherical resin particles, for example, spherical resin particles by suspension polymerization method, dispersion polymerization method or the like are used. Spherical resin particles can have a suitable surface roughness with a smaller addition amount, and a uniform surface shape can be easily obtained. Examples of such spherical resin particles include acrylic resin particles such as polyacrylate and polymethacrylate, polyamide resin particles such as nylon, polyolefin resin particles such as polyethylene and polypropylene, silicone resin particles, phenolic resin particles, Examples include polyurethane resin particles, styrene resin particles, benzoguanamine particles, and the like. The resin particles obtained by the pulverization method may be used after thermally or physically spheroidizing.

For example, an inorganic fine powder may be adhered to or adhered to the surface of the spherical resin particles. Examples of such inorganic fine powder include SiO ₂ , SrTiO ₃ , CeO ₂ , CrO, Al ₂ O ₃ , ZnO, MgO, oxides such as Si ₃ N ₄ , carbides such as SiC, CaSO ₄ , Examples thereof include sulfates and carbonates such as BaSO ₄ and CaCO ₃ .

  Such inorganic fine powder may be used after being treated with a coupling agent. In particular, it can be preferably used for the purpose of improving the adhesion to the binder resin, or for imparting hydrophobicity to the particles. Examples of such a coupling agent include a silane coupling agent, a titanium coupling agent, and a zircoaluminate coupling agent. More specifically, for example, as a silane coupling agent, hexamethyldisilazane, trimethylsilane, trimethylchlorosilane, trimethylethoxysilane, dimethyldichlorosilane, methyltrichlorosilane, allyldimethylchlorosilane, allylphenyldichlorosilane, Benzyldimethylchlorosilane, bromomethyldimethylchlorosilane, α-chloroethyltrichlorosilane, β-chloroethyltrichlorosilane, chloromethyldimethylchlorosilane, triorganosilylmercaptan, trimethylsilylmercaptan, triorganosilylacrylate, vinyldimethylacetoxysilane, dimethyl Diethoxysilane, dimethyldimethoxysilane, diphenyldiethoxysilane, hexamethyldisiloxane, 1,3-divinyltet Lamethyldisiloxane, 1,3-diphenyltetramethyldisiloxane, and dimethyl containing 2 to 12 siloxane units per molecule, each containing a hydroxyl group bonded to one silicon atom at each terminal unit Polysiloxane etc. are mentioned.

  By treating the surface of the spherical resin particles with the inorganic fine powder in this way, dispersibility in the paint, uniformity of the coating surface, stain resistance of the coating, charge imparting property to the toner, and resistance of the coating layer are achieved. Abrasion and the like can be improved.

  Further, by imparting conductivity to the spherical particles, it is difficult to accumulate charges on the particle surface due to the conductivity, and it is possible to reduce toner adhesion and to improve toner chargeability. As a method for obtaining such conductive spherical particles, the following methods are preferable, but are not necessarily limited to these methods.

As a method for obtaining particularly preferable conductive spherical particles used in the present invention, resin-based spherical particles such as phenol resin, naphthalene resin, furan resin, xylene resin, divinylbenzene polymer, styrene-divinylbenzene copolymer, polyacrylonitrile, etc. Low density and good conductivity spherical carbon particles obtained by carbonizing and / or graphitizing particles and mesocarbon microbeads by firing, more preferably phenol resin, naphthalene resin, furan resin, xylene resin, divinyl The surface of spherical particles such as benzene polymer, styrene-divinylbenzene copolymer, polyacrylonitrile, etc. is coated with bulk mesophase pitch by mechanochemical method, heat-treated in an oxidizing atmosphere, and then fired to carbonize and / or graphite. It is the conductive spherical carbon particle obtained by making it. The spherical carbon particles obtained by these methods can control the conductivity to some extent by changing the firing conditions and the like in any method. In addition, the spherical carbon particles obtained by these methods are optionally plated with a conductive metal and / or metal oxide so that the true density does not exceed ³ g / cm ³ in order to further increase the conductivity. May be.

  As another method for obtaining conductive spherical particles preferably used in the present invention, conductive fine particles smaller than the particle diameter of the core particles are mechanically mixed on the surface of the core particles made of spherical resin particles at an appropriate blending ratio. Then, after the conductive fine particles are uniformly attached around the resin particles by the action of van der Waals force and electrostatic force, the surface of the resin particles is softened by the local temperature rise caused by, for example, mechanical impact force. Examples thereof include conductively treated spherical resin particles formed with fine particles. As the constituent material of the mother particles, it is preferable to use a resin which is a spherical organic compound having a low core density. For example, PMMA, acrylic resin, polybutadiene resin, polystyrene resin, polyethylene, polypropylene, polybutadiene, or a combination thereof. Resin particles such as a polymer, a benzoguanamine resin, a phenol resin, a polyamide resin, nylon, a fluorine resin, a silicone resin, an epoxy resin, and a polyester resin can be used. Further, as the conductive fine particles which are small particles, the particle size of the small particles is preferably 1/8 or less than the particle size of the mother particles in order to uniformly coat the conductive fine particles.

  As still another method for obtaining conductive spherical particles preferably used in the present invention, conductive fine particles are uniformly dispersed in spherical resin particles. For example, conductive fine particles are dispersed in a binder resin. After kneading, pulverize to the prescribed particle size, and add spherical initiator particles, conductive initiators and other additives to the polymerizable monomer. The conductive fine particles obtained by suspending the monomer composition uniformly dispersed by a disperser or the like in a water phase containing a dispersion stabilizer so as to have a predetermined particle diameter by a stirrer or the like and performing polymerization Examples include dispersed spherical particles.

  The conductive fine particle-dispersed spherical particles obtained by these methods are mechanically mixed with the conductive fine particles having a particle size smaller than the above-mentioned core particles at an appropriate blending ratio, and conductive by van der Waals force and electrostatic force. After the conductive fine particles are uniformly attached around the conductive fine particle-dispersed spherical particles, the surface of the conductive fine particle-dispersed resin particles is softened by a local temperature rise caused by, for example, a mechanical impact force, and the conductive fine particles are formed, Further, the conductivity may be increased for use.

  The surface roughness of the resin coating layer on the surface of the developer carrying member is preferably in the range of 0.1 μm to 3.5 μm in terms of JIS arithmetic average roughness (Ra). More preferably, it is 0.3 micrometer-2.5 micrometers. If Ra is less than 0.1 μm, the charge amount of the magnetic developer on the developer carrying member becomes too high and the developability may be insufficient, and the transportability of the developer to the development area is inferior, It becomes difficult to obtain a sufficient image density. On the other hand, if Ra exceeds 3.5 μm, the magnetic developer layer formed on the developer carrying member may be uneven, which may cause density unevenness on the image.

  For measurement of surface roughness, either a stylus type roughness meter or a non-contact type roughness meter can be suitably applied, and there is no particular problem if the method is performed in accordance with the provisions of JIS B0601 2001. The surface roughness Ra of the resin coating layer was measured using a surf coder SE-3500 manufactured by Kosaka Laboratories. The measurement conditions were a cutoff of 0.8 mm, an evaluation length of 4 mm, and a feed rate of 0.5 mm / sec. X Measurement was made for 3 points in the circumferential direction = 9 points, and the average value was taken.

  In the resin coating layer of this invention, a charge control agent can be contained as needed. As the charge control agent, those similar to those used for the toner particle formation described above can be used.

  In the present invention, when a negatively chargeable toner is used as the magnetic developer, in the conductive resin coating layer of the developer carrying member as disclosed in JP 2002-31636 A or JP 2003-057951 A. The magnetic developer may contain a charge-controllable nitrogen-containing compound. In this case, the nitrogen-containing compound is a quaternary ammonium salt compound that is positively charged with respect to iron powder. It is preferable in terms of good charge imparting properties. At this time, the resin coating layer preferably has at least one of an amino group, ═NH group, and —NH— bond in the resin structure in terms of good charge imparting property to the magnetic developer. .

  Here, the relationship between the magnetic developer and the resin coating layer in the developing device will be described. When the magnetic developer is used as a negatively chargeable toner, for example, since it has a strong negative chargeability compared to conventional toners, it can achieve high chargeability, uniform charge amount, and environmental stability of charge characteristics as a toner. However, toner fusion and charge-up are likely to occur. Therefore, also in the present invention, by adding the quaternary ammonium salt compound to the resin coating layer, combined with effects such as charge imparting to the resin coating layer by the graphitized particles having a specific degree of graphitization, lubricity and the like. In particular, it is possible to obtain high charging stability and conveyance stability with respect to the magnetic developer that is particularly prone to charge-up and the like. As a result, it is possible to maintain the high charging stability of the magnetic developer and to provide a high-definition image having environmental stability and long-term stability.

  In the present invention, if the binder resin in the resin coating layer is configured as described above, there is no clear reason why the resin coating layer becomes a good charge imparting substance for the magnetic developer. Is estimated as follows.

  When added to the binder resin, the quaternary ammonium salt compound that is positively charged with respect to iron powder itself contains at least one of an amino group, ═NH, or —NH— in the structure. The binder resin is uniformly dispersed in the binder resin and further taken into the structure of the binder resin when the resin coating layer is formed, so that the binder resin composition itself having the compound has a negative chargeability. It is considered a thing.

  For this reason, the resin coating layer acts on the negatively chargeable toner in a direction that prevents the toner from having an excessive negative charge amount, and as a result, the negative charge amount of the magnetic developer can be appropriately controlled. It becomes.

  The triboelectric charge amount between the negatively chargeable toner and the resin coating layer of the developer carrying member was measured with a surface charge amount measuring apparatus (TS100AS manufactured by Toshiba Chemical Corporation) as shown in FIG. The crushed material of the negatively chargeable toner is sieved with a mesh, and the remaining resin between 60 mesh and 100 mesh and the binder resin containing a quaternary ammonium salt compound that is positively charged with respect to iron powder are SUS plate. What was apply | coated to was used. FIG. 5 is a graph showing the relationship between the charge amount of the model toner and the addition amount of the quaternary ammonium salt compound to the binder resin used in the resin coating layer of the present invention. As shown in FIG. 5, in the PMMA resin that does not contain an amino group, ═NH or —NH— in the structure, no change in charge amount due to addition is observed.

  The quaternary ammonium salt compound may be any compound as long as it has a positive chargeability with respect to iron powder, and examples thereof include compounds represented by the following general formula.

（式中のＲ₁、Ｒ₂、Ｒ₃及びＲ₄は、夫々置換基を有してもよいアルキル基、置換基を有してもよいアリール基、アルアルキル基を表し、Ｒ₁〜Ｒ₄は夫々同一でも或いは異なっていても良い。Ｘ^-は酸の陰イオンを表す。）

(Wherein R ₁ , R ₂ , R ₃ and R ₄ represent an alkyl group which may have a substituent, an aryl group which may have a substituent, and an aralkyl group, respectively, R _{1 to} R ₄ may be the same or different, and X ⁻ represents an anion of an acid.)

In the aforementioned general formula, specific examples of the acid ion of X 2 ⁻ include organic sulfate ion, organic sulfonate ion, organic phosphate ion, molybdate ion, tungstate ion, heteropolyacid ion containing molybdenum atom or tungsten atom, etc. Is preferably used.

  On the other hand, for example, a fluorine-containing quaternary ammonium salt compound having a negative chargeability with respect to iron powder as represented by the following structural formula was also studied. It has been found that the desired object of the present invention is not achieved. That is, since the compound represented by the following structural formula has a fluorine atom having a strong electron-withdrawing property in the structure, the compound itself has a negative chargeability with respect to the iron powder. Even if the compound is dispersed in a binder resin containing at least one of an amino group, = NH or -NH- in the structure, and this is heat-cured to form a resin coating layer on the developer carrier, To the extent that it is used for a binder resin containing the quaternary ammonium salt compound containing no fluorine, the overcharge suppression property against the negatively chargeable magnetic developer was not obtained.

  Specific examples of the quaternary ammonium salt compound suitably used in the present invention include the following, but of course, the present invention is not limited thereto.

  The amount of the quaternary ammonium salt compound as exemplified above is 1 to 100 parts by mass with respect to 100 parts by mass of the binder resin containing at least one of an amino group, ═NH or —NH— in the structure. It is preferable to set it as a mass part. If the amount is less than 1 part by mass, the charge imparting property may not be improved by addition. If the amount exceeds 100 parts by mass, the dispersion in the binder resin becomes poor and the coating strength tends to decrease.

  As the binder resin containing at least one of an amino group, = NH or -NH- in the structure, a phenol resin, a polyamide resin, and a polyamide produced using a nitrogen-containing compound as a catalyst in the production process are curing agents. Examples thereof include an epoxy resin, a urethane resin, and a copolymer partially containing these resins. The quaternary ammonium salt compound is easily taken into the structure of the binder resin when forming a mixture with these binder resins.

  Examples of the nitrogen-containing compound used as the catalyst include ammonium salts such as ammonium sulfate, ammonium phosphate, ammonium sulfamate, ammonium carbonate, ammonium acetate, and ammonium maleate, and amine salts. Basic catalysts include ammonia; dimethylamine, diethylamine, diisopropylamine, diisobutylamine, diamylamine, trimethylamine, triethylamine, tri-n-butylamine, triamylamine, dimethylbenzylamine, diethylbenzylamine, dimethylaniline, diethylaniline, N , N-di-n-butylaniline, N, N-diamilaniline, N, N-di-t-amylaniline, N-methylethanolamine, N-ethylethanolamine, diethanolamine, triethanolamine, dimethylethanolamine , Diethylethanolamine, ethyldiethanolamine, n-butyldiethanolamine, di-n-butylethanolamine, triisopropanolamine, ethylenediamine, hexamethyl Amino compounds such as lentetramine; pyridine and derivatives thereof such as pyridine, α-picoline, β-picoline, γ-picoline, 2,4-lutidine, 2,6-lutidine; quinoline compounds, imidazole, 2-methylimidazole, 2 , 4-dimethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, imidazole such as 2-heptadecylimidazole, and nitrogen-containing heterocyclic compounds such as derivatives thereof. Can be mentioned.

  Examples of the polyamide resin used as the binder resin described above include nylon 6, 66, 610, 11, 12, 9, 13, Q2 nylon, etc., and a nylon copolymer mainly composed of these, N- Examples thereof include alkyl-modified nylon and N-alkoxylalkyl-modified nylon, and any of them can be suitably used. Furthermore, any resin containing a polyamide resin such as various resins modified with polyamide such as a polyamide-modified phenol resin or an epoxy resin using a polyamide resin as a curing agent may be used. It can be used suitably.

  In addition, as the urethane resin used as the binder resin described above, any resin including a urethane bond can be suitably used. This urethane bond is obtained by polymerization addition reaction of polyisocyanate and polyol.

  Polyisocyanates that are the main raw materials for this polyurethane resin include TDI (tolylene diisocyanate), pure MDI (diphenylmethane diisocyanate), polymeric MDI (polymethylene polyphenyl polyisocyanate), TODI (tolidine diisocyanate), NDI (naphthalene diisocyanate), and the like. Aromatic polyisocyanates such as: HMDI (hexamethylene diisocyanate), IPDI (isophorone diisocyanate), XDI (xylylene diisocyanate), hydrogenated XDI (hydrogenated xylylene diisocyanate), aliphatic MDI (dicyclohexylmethane diisocyanate), etc. And polyisocyanates.

  Polyols that are the main raw materials for this polyurethane resin include polyether polyols such as PPG (polyoxypropylene glycol), polymer polyols, and polytetramethylene glycol (PTMG); polyester polyols such as adipate, polycaprolactone, and polycarbonate polyols. Polyether modified polyols such as PHD polyol and polyether ester polyol; other epoxy-modified polyols; partially saponified polyols of ethylene-vinyl acetate copolymer (saponified EVA); flame retardant polyols and the like.

  In the present invention, the resin coating layer of the developer carrying member may contain an unsubstituted or substituted benzylic acid metal compound represented by the following general formula (B). It is preferable that the acid metal compound is the aluminum compound of benzyl acid from the viewpoint of good charge imparting property to the magnetic developer.

（式中、Ｒ₁とＲ₂は同一であっても異なっていても良く、それぞれ独立して、直鎖又は分岐したアルキル基、直鎖又は分岐したアルケニル基、直鎖又は分岐したアルコキシル基、ハロゲン原子、ニトロ基、シアノ基、アミノ基、カルボキシル基及び水酸基からなるグループから選ばれる置換基を示し、ｍ及びｎは０〜５の整数を示す。）

(In the formula, R ₁ and R ₂ may be the same or different, and each independently represents a linear or branched alkyl group, a linear or branched alkenyl group, a linear or branched alkoxyl group, A substituent selected from the group consisting of a halogen atom, a nitro group, a cyano group, an amino group, a carboxyl group and a hydroxyl group is shown, and m and n are integers of 0 to 5.)

  Further, the aluminum compound of benzyl acid is preferably an aluminum compound of benzyl acid represented by the following general formula (B-1), but if it is a complex and / or complex salt composed of 2 mol of benzyl acid and 1 mol of aluminum atom. It is not limited to the general formula (B-1).

（式中、Ｒ₁とＲ₂は同一であっても異なっていても良く、各々独立して、直鎖又は分岐したアルキル基、アルケニル基、アルコキシル基、ハロゲン原子、ニトロ基、シアノ基、アミノ基、カルボキシル基及び水酸基からなるグループから選ばれる置換基を示し、ｍ及びｎは０乃至５の整数を示す。また、Ｘ＋は１価のカチオンを示し、Ｘは水素、リチウム、ナトリウム、カリウム、アンモニウム又はアルキルアンモニムを表す。）

(In the formula, R ₁ and R ₂ may be the same or different, and each independently represents a linear or branched alkyl group, alkenyl group, alkoxyl group, halogen atom, nitro group, cyano group, amino group. A substituent selected from the group consisting of a group, a carboxyl group and a hydroxyl group, m and n each represent an integer of 0 to 5. X + represents a monovalent cation, X represents hydrogen, lithium, sodium, potassium, Represents ammonium or alkylammonium)

  Other examples of the aluminum compound of benzylic acid include an aluminum complex and / or complex salt in which one molecule of benzylic acid is coordinated, an aluminum complex and / or complex salt in which three molecules of benzylic acid are coordinated, and benzylic acid Mixtures of aluminum complexes and / or complex salts in which 1 to 3 molecules of the compound are coordinated can also be used.

  The number of carbon atoms of the substituents represented by the general formulas (B) and (B-1) is not particularly limited, but is in the range of (0 to 12). Or from the viewpoint of dispersibility in the resin coating layer.

  The aluminum compound of benzyl acid was obtained, for example, by mixing an unsubstituted or substituted benzyl acid as described above and an aluminum salt such as aluminum sulfate in a desired molar ratio and heating and reacting in an alkaline atmosphere. The precipitate can be collected by filtration, washed with water and dried. However, the method for producing the aluminum compound of benzyl acid according to the present invention is not limited to this.

  The aluminum compound of benzyl acid dispersed in the resin coating layer has the effect of suppressing the charge amount for negative toners having a high charge amount, and the appropriate charge amount for a negatively chargeable magnetic developer. Can be applied uniformly. As a result, image density reduction, sleeve ghosting, fogging, and the like can be prevented, and blotting due to charge-up can be more effectively prevented.

  The content of the aluminum compound of benzyl acid dispersed in the resin coating layer is 1 part by mass to 100 parts by mass, more preferably 2 parts by mass to 50 parts by mass with respect to 100 parts by mass of the binder resin. . When the addition amount is less than 1 part by mass, the effect of the addition may be insufficient, and when it exceeds 100 parts by mass, the environmental stability of the resin coating layer may be insufficient.

  Examples of the binder resin used for the resin coating layer containing the metal compound of benzyl acid include, for example, styrene resin, vinyl resin, polyethersulfone resin, polycarbonate resin, polyphenylene oxide resin, polyamide resin, fluororesin, Thermoplastic resins such as fiber-based resins and acrylic resins; thermal or photo-curable resins such as epoxy resins, polyester resins, alkyd resins, phenol resins, melamine resins, polyurethane resins, urea resins, silicone resins and polyimide resins; Can be used.

  Among these, those having releasability such as silicone resin and fluorine resin, or polyether sulfone resin, polycarbonate resin, polyphenylene oxide resin, polyamide resin, phenol resin, polyester resin, polyurethane resin, styrene resin and acrylic resin Those having excellent mechanical properties such as resin are more preferred.

  In the developing method using a magnetic developer, a magnetic field generating means such as a magnet roller constituted by a magnet is provided in the developer carrying body in order to magnetically attract and hold the magnetic developer on the developer carrying body. Deploy. In that case, the substrate may be cylindrical, and a magnet roller may be disposed therein.

  Hereinafter, the structure of the resin coating layer in the developer carrier used in the present invention will be described. FIG. 2 is a cross-sectional view schematically showing a part of an example of the developer carrying member used in the present invention. In FIG. 2, a resin coating layer 201 in which a solid lubricant 205, conductive fine particles 203, roughening material or reinforcing particles 202 are dispersed in a binder resin 204 is laminated on a base body 206 made of a metal cylindrical tube. Yes.

  As the binder resin for toner used in the magnetic developer, polyester resin, styrene-acrylic resin, hybrid resin containing polyester resin component and styrene-acrylic resin component, epoxy resin, styrene-butadiene resin, polyurethane resin However, it is not particularly limited, and a conventionally known resin can be used. Of these, polyester resins and hybrid resins are particularly preferred from the standpoint of fixing properties.

  The polyester resin is a resin formed by polycondensation of a polyhydric alcohol and a polybasic acid, and examples of the monomer of the polyester resin component include the following.

  Examples of the divalent alcohol component include ethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, diethylene glycol, triethylene glycol, 1,5-pentanediol, 1, 6-hexanediol, neopentyl glycol, 2-ethyl-1,3-hexanediol, hydrogenated bisphenol A, bisphenol derivatives represented by the following formula (a), and diols represented by the following formula (a): Can be mentioned.

  Divalent carboxylic acids include benzene dicarboxylic acids such as phthalic acid, terephthalic acid, isophthalic acid, and phthalic anhydride, or anhydrides thereof; alkyl dicarboxylic acids such as succinic acid, adipic acid, sebacic acid, and azelaic acid, or anhydrides thereof. A succinic acid substituted with an alkyl group having 6 to 18 carbon atoms or an anhydride thereof; an unsaturated dicarboxylic acid such as fumaric acid, maleic acid, citraconic acid, itaconic acid, or an anhydride thereof;

  Other monomers of the polyester resin include glycerin, pentaerythritol, sorbit, sorbitan, and polyhydric alcohols such as oxyalkylene ethers of novolak type phenol resins; trimellitic acid, pyromellitic acid, benzophenone tetracarboxylic acid And polyhydric carboxylic acids such as anhydride thereof.

  The styrene-acrylic resin is a resin produced by addition polymerization of a styrene monomer and an acrylic acid monomer, and examples of vinyl monomers for producing a styrene-acrylic resin include the following. .

  Styrene monomers include styrene, o-methyl styrene, m-methyl styrene, p-methyl styrene, p-phenyl styrene, p-ethyl styrene, 2,4-dimethyl styrene, pn-butyl styrene, p-tert. -Butyl styrene, pn-hexyl styrene, pn-octyl styrene, pn-nonyl styrene, pn-decyl styrene, pn-dodecyl styrene, p-methoxy styrene, p-chlorostyrene, 3 Styrene and its derivatives such as 1,4-dichlorostyrene, m-nitrostyrene, o-nitrostyrene, p-nitrostyrene.

  Examples of acrylic monomers include acrylic acid, methyl acrylate, ethyl acrylate, propyl acrylate, acrylic acid-n-butyl, acrylic acid isobutyl, acrylic acid-n-octyl, acrylic acid dodecyl, acrylic acid-2- Acrylic acid and acrylic esters such as ethylhexyl, stearyl acrylate, 2-chloroethyl acrylate, phenyl acrylate, methacrylic acid, methyl methacrylate, ethyl methacrylate, propyl methacrylate, methacrylic acid-n-butyl, methacrylic acid Such as isobutyl acid, n-octyl methacrylate, dodecyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, phenyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate And α- methylene aliphatic monocarboxylic acids and esters thereof, acrylonitrile, methacrylonitrile, and the like such as acrylic acid or methacrylic acid derivatives of acrylamide.

  Furthermore, as a monomer of styrene-acrylic resin, acrylic acid or methacrylic acid esters such as 2-hydroxylethyl acrylate, 2-hydroxylethyl methacrylate, 2-hydroxylpropyl methacrylate, 4- (1-hydroxy-1-methylbutyl) Examples thereof include monomers having a hydroxyl group such as styrene and 4- (1-hydroxy-1-methylhexyl) styrene.

  In the styrene-acrylic resin, various monomers capable of vinyl polymerization can be used in combination as required. Such monomers include ethylene unsaturated monoolefins such as ethylene, propylene, butylene and isobutylene; unsaturated polyenes such as butadiene and isoprene; halogenated compounds such as vinyl chloride, vinylidene chloride, vinyl bromide and vinyl fluoride. Vinyls; vinyl esters such as vinyl acetate, vinyl propionate and vinyl benzoate; vinyl ethers such as vinyl methyl ether, vinyl ethyl ether and vinyl isobutyl ether: vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone and methyl isopropenyl ketone N-vinyl compounds such as N-vinyl pyrrole, N-vinyl carbazole, N-vinyl indole, N-vinyl pyrrolidone; vinyl naphthalenes; and maleic acid, citraconic acid, itaconic acid, al Unsaturated dibasic acids such as succinic acid, fumaric acid, mesaconic acid; unsaturated dibasic acid anhydrides such as maleic anhydride, citraconic anhydride, itaconic anhydride, alkenyl succinic anhydride; methyl half maleate Esters, ethyl maleate half ester, butyl maleate half ester, citraconic acid methyl half ester, citraconic acid ethyl half ester, citraconic acid butyl half ester, itaconic acid methyl half ester, alkenyl succinic acid methyl half ester, fumarate methyl half ester Unsaturated basic acid esters such as mesaconic acid methyl half ester; Unsaturated basic acid esters such as dimethylmaleic acid and dimethylfumaric acid; α, β-unsaturated such as acrylic acid, methacrylic acid, crotonic acid and cinnamic acid Acid acid Water anhydrides; anhydrides of the α, β-unsaturated acids and lower fatty acids; and monomers having a carboxyl group such as alkenylmalonic acid, alkenylglutaric acid, alkenyladipic acid, acid anhydrides and monoesters thereof. It is done.

  The styrene-acrylic resin may be a polymer cross-linked with a cross-linkable monomer as exemplified below if necessary. Crosslinkable monomers include, for example, aromatic divinyl compounds, diacrylate compounds linked by alkyl chains, diacrylate compounds linked by alkyl chains containing ether bonds, and chains containing aromatic groups and ether bonds. And diacrylate compounds, polyester-type diacrylates, and polyfunctional crosslinking agents.

  Examples of the aromatic divinyl compound include divinylbenzene and divinylnaphthalene.

  Examples of diacrylate compounds linked by an alkyl chain include ethylene glycol diacrylate, 1,3-butylene glycol diacrylate, 1,4-butanediol diacrylate, 1,5-pentanediol diacrylate, 1,6- Examples include hexanediol diacrylate, neopentyl glycol diacrylate, and those obtained by replacing the acrylate of the above compound with methacrylate.

  Examples of diacrylate compounds linked by an alkyl chain containing an ether bond include diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol # 400 diacrylate, polyethylene glycol # 600 diacrylate, and dipropylene. Examples include glycol diacrylate and those obtained by replacing acrylate of the above compound with methacrylate.

  Examples of diacrylate compounds linked by a chain containing an aromatic group and an ether bond include polyoxyethylene (2) -2,2-bis (4-hydroxyphenyl) propane diacrylate, polyoxyethylene (4)- Examples include 2,2-bis (4-hydroxyphenyl) propane diacrylate, and those obtained by replacing the acrylate of the above compound with methacrylate.

  Examples of polyester diacrylates include trade name MANDA (Nippon Kayaku).

  Examples of the polyfunctional crosslinking agent include pentaerythritol triacrylate, trimethylol ethane triacrylate, trimethylol propane triacrylate, tetramethylol methane tetraacrylate, oligoester acrylate, and those obtained by replacing the acrylate of the above compounds with methacrylate; And allyl cyanurate and triallyl trimellitate.

  These crosslinkable monomers can be used in an amount of 0.01 to 10 parts by mass (more preferably 0.03 to 5 parts by mass) with respect to 100 parts by mass of other monomer components. Among these cross-linkable monomers, those which are preferably used from the viewpoint of fixability and offset resistance are aromatic divinyl compounds (particularly divinylbenzene) and divalent groups connected by a chain containing an aromatic group and an ether bond. Examples include acrylate compounds.

  The styrene-acrylic resin may be a resin produced using a polymerization initiator. Examples of such a polymerization initiator include 2,2′-azobisisobutyronitrile, 2,2′-azobis (4-methoxy-2,4-dimethylvaleronitrile), 2,2′-azobis (2 , 4-dimethylvaleronitrile), 2,2′-azobis (2-methylbutyronitrile), dimethyl-2,2′-azobisisobutyrate, 1,1′-azobis (1-cyclohexanecarbonitrile), 2-carbamoylazoisobutyronitrile, 2,2′-azobis (2,4,4-trimethylpentane), 2-phenylazo-2,4-dimethyl-4-methoxyvaleronitrile, 2,2′-azobis ( 2-methylpropane), methylethylketone peroxide, acetylacetone peroxide, ketone peroxide such as cyclohexanone peroxide 2,2-bis (t-butylperoxy) butane, t-butyl hydroperoxide, cumene hydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide, di-t-butyl peroxide, t-Butylcumyl peroxide, dicumyl peroxide, α, α'-bis (t-butylperoxyisopropyl) benzene, isobutyl peroxide, octanoyl peroxide, decanoyl peroxide, lauroyl peroxide, 3,5,5 5-trimethylhexanoyl peroxide, benzoyl peroxide, m-trioyl peroxide, diisopropyl peroxydicarbonate, di-2-ethylhexyl peroxydicarbonate, di-n-propyl peroxydicarbonate, di-2- D Xylethylperoxycarbonate, dimethoxyisopropylperoxydicarbonate, di (3-methyl-3-methoxybutyl) peroxycarbonate, acetylcyclohexylsulfonyl peroxide, t-butylperoxyacetate, t-butylperoxyisobutyrate, t-butylperoxyneodecanoate, t-butylperoxy-2-ethylhexanoate, t-butylperoxylaurate, t-butylperoxybenzoate, t-butylperoxyisopropylcarbonate, di-t -Butyl peroxyisophthalate, t-butyl peroxyallyl carbonate, t-amyl peroxy-2-ethyl hexanoate, di-t-butyl peroxy hexahydroterephthalate, di-t-butyl peroxya Rate, and the like.

  The hybrid resin is a resin in which a polyester resin component and a styrene-acrylic resin component are directly or indirectly chemically bonded, and the above-mentioned polyester resin component, styrene-acrylic resin component, and these resin components It is comprised from the monomer component which can react with both.

  Examples of the monomer constituting the polyester resin component that can react with the styrene-acrylic resin component include unsaturated dicarboxylic acids such as fumaric acid, maleic acid, citraconic acid, and itaconic acid, or anhydrides thereof.

  Among the monomers constituting the styrene-acrylic resin component, those capable of reacting with the polyester resin component include those having a carboxyl group or a hydroxyl group, and acrylic acid or methacrylic acid esters.

  As a method for obtaining a hybrid resin, the monomer component capable of reacting with each of the polyester resin and the styrene-acrylic resin listed above is present, and is obtained by polymerizing one or both resins. The method is preferred.

  Examples of the magnetic material used in the magnetic developer include iron oxides such as magnetite, maghemite, and ferrite, and iron oxides including other metal oxides; metals such as Fe, Co, and Ni, or these metals and Al, And alloys with metals such as Co, Cu, Pb, Mg, Ni, Sn, Zn, Sb, Be, Bi, Cd, Ca, Mn, Se, Ti, W, and V; and mixtures thereof.

Conventionally, as a magnetic material, triiron tetroxide (Fe ₃ O ₄ ), iron sesquioxide (γ-Fe ₂ O ₃ ), iron oxide zinc (ZnFe ₂ O ₄ ), iron yttrium oxide (Y ₃ Fe ₅ O _12). ), Iron cadmium oxide (CdFe ₂ O ₄ ), iron gadolinium oxide (Gd ₃ Fe ₅ O ₁₂ ), iron oxide copper (CuFe ₂ O ₄ ), iron oxide lead (PbFe ₁₂ O ₁₉ ), nickel iron oxide (NiFe ₂₎ O ₄ ), neodymium iron oxide (NdFe ₂ O ₃ ), barium oxide (BaFe ₁₂ O ₁₉ ), magnesium iron oxide (MgFe ₂ O ₄ ), manganese iron oxide (MnFe ₂ O ₄ ), iron lanthanum oxide (LaFeO ₃₎ ), Iron powder (Fe), cobalt powder (Co), nickel powder (Ni), etc. are known, but in the present invention, one or more of the above-mentioned magnetic materials may be arbitrarily selected and used. Is possible.

These magnetic materials have an average particle size of about 0.1 μm to 2 μm, and the magnetic properties when 795.8 kA / m (10 k Oersted) is applied are such that the coercive force (Hc) is 1.5 kA / m to 12 kA / m, saturation magnetization ([sigma] s) is 50Am ² / kg~200Am ² / kg (preferably 50~100Am ² / kg), it is preferable residual magnetization (.sigma.r) is 2Am ² / kg~20Am ² / kg. The magnetic properties of the magnetic material can be measured using a vibration magnetometer such as VSM P-1-10 (manufactured by Toei Kogyo Co., Ltd.) under the conditions of 25 ° C. and an external magnetic field of 769 kA / m.

  In the present invention, the magnetic material can also function as a colorant. From the viewpoint of a colorant, the magnetic material is preferably magnetic iron oxide. Examples of such magnetic iron oxide include fine powders of triiron tetroxide and γ-iron sesquioxide. Further, this magnetic iron oxide exhibits good magnetism that prevents toner scattering while maintaining fluidity when the toner particles contain 20 parts by mass to 150 parts by mass with respect to 100 parts by mass of the binder resin. It is preferable for developing sufficient coloring power.

  In the present invention, the magnetic material is appropriately used by using an appropriate surface hydrophobizing agent such as a silane coupling agent or silicone oil according to the intended physical properties of the magnetic developer and the manufacturing conditions of the magnetic developer. The surface may be hydrophobized.

  In the present invention, other additives may be added to the magnetic developer particles as necessary. As such other additives, various additives conventionally known to be added to the inside of magnetic developer particles can be used, and examples thereof include a release agent and a charge control agent.

  Preferred examples of the release agent include aliphatic hydrocarbon waxes such as low molecular weight polyethylene, low molecular weight polypropylene, microcrystalline wax, and paraffin wax; oxides of aliphatic hydrocarbon waxes such as oxidized polyethylene wax or the like. Block copolymers of these: waxes based on fatty acid esters such as carnauba wax, sazol wax, and montanic acid ester wax; deoxidized part or all of fatty acid esters such as deoxidized carnauba wax Saturated fatty acids such as palmitic acid, stearic acid, and montanic acid; unsaturated fatty acids such as brassic acid, eleostearic acid, and parinalic acid; stearyl alcohol, aralkyl alcohol, behenyl alcohol, carnauvyl alcohol, seryl alcohol Saturated alcohols such as melyl alcohol, polyhydric alcohols such as sorbitol; Fatty acid amides such as linoleic acid amide, oleic acid amide, lauric acid amide; Methylene bis stearic acid amide, ethylene biscapric acid amide, ethylene bis Saturated fatty acid bisamides such as lauric acid amide and hexamethylene bis stearic acid amide; ethylene bis oleic acid amide, hexamethylene bis oleic acid amide, N, N′-dioleyl adipic acid amide, N, N′-dioleyl sebacic acid Unsaturated fatty acid amides such as amides; Aromatic bisamides such as m-xylene bis-stearic acid amide and N, N′-distearylisophthalic acid amide; Calcium stearate, calcium laurate, zinc stearate, magnesium stearate, etc. Aliphatic metal salts (generally referred to as metal soaps); waxes grafted with aliphatic hydrocarbon waxes using vinyl monomers such as styrene and acrylic acid; fatty acids such as behenic acid monoglycerides Examples include partially esterified products of monohydric alcohols; methyl ester compounds having a hydroxyl group obtained by hydrogenation of vegetable oils and fats; long-chain alkyl alcohols or long-chain alkyl carboxylic acids having 12 or more carbon atoms; and the like.

  Examples of the release agent particularly preferably used in the present invention include aliphatic hydrocarbon waxes. As such an aliphatic hydrocarbon wax, for example, a low molecular weight alkylene polymer obtained by radical polymerization of alkylene at a high pressure or a Ziegler catalyst under a low pressure; a high molecular weight alkylene polymer is thermally decomposed. The resulting alkylene polymer; a synthetic hydrocarbon wax obtained from the distillation residue of hydrocarbons obtained from the synthesis gas containing carbon monoxide and hydrogen by the age method; and a synthetic hydrocarbon wax obtained by hydrogenating it; these fats Group hydrocarbon waxes are classified by press sweating, solvent method, vacuum distillation and fractional crystallization.

  Examples of the hydrocarbon as the matrix of the aliphatic hydrocarbon wax include those synthesized by the reaction of carbon monoxide and hydrogen using a metal oxide catalyst (often a multi-component system of two or more types) (for example, Hydrocarbon compounds synthesized by the Gintor method and Hydrocol method (using a fluidized catalyst bed); Up to a few hundred carbon atoms obtained by the Age method (using an identified catalyst bed) in which many waxy hydrocarbons can be obtained A hydrocarbon obtained by polymerizing an alkylene such as ethylene with a Ziegler catalyst. Among such hydrocarbons, in the present invention, it is preferable that the hydrocarbon is a linear hydrocarbon having a small number of branches and a long saturation, and a hydrocarbon synthesized by a method not based on polymerization of alkylene has a molecular weight. Also preferred from the distribution.

  In the present invention, the release agent is magnetic so that an endothermic main peak appears in the region of 70 ° C. to 140 ° C. in the obtained DSC curve when the magnetic developer particles containing the release agent are measured with a differential scanning calorimeter. It is preferable that it is contained in the developer particles in terms of the low-temperature fixability and high-temperature offset resistance of the magnetic developer.

  The temperature at which the endothermic main peak appears can be measured according to ASTM D3418-82 using a highly accurate internal heat input compensation type differential scanning calorimeter, for example, DSC-7 manufactured by PerkinElmer. The temperature at which the endothermic main peak appears can be adjusted by using a release agent in which the melting point, glass transition point, polymerization degree, and the like are appropriately adjusted. In addition to the temperature at which the endothermic main peak appears, the DSC-7 has the magnetic properties of the magnetic developer particles and their materials, such as the glass transition point of the binder resin for toner, the softening point, and the melting point of the release agent. It can be applied to the measurement of temperature indicating

  The release agent is preferably contained in the magnetic developer particles in an amount of 2 to 15 parts by mass per 100 parts by mass of the binder resin for toner from the viewpoint of fixability and charging characteristics.

  In the magnetic developer used in the present invention, a charge control agent can be used in order to stabilize the chargeability as long as the effects of the present invention are not impaired. The charge control agent varies depending on the type of charge control agent and the physical properties of other constituent materials of the magnetic developer particles, but generally 0.1 mass part per 100 mass parts of the binder resin for toner in the magnetic developer particles. It is preferable that 10 mass parts is contained, and it is more preferable that 0.1 mass parts-5 mass parts is contained.

  As the charge control agent, those that control the magnetic developer to be negatively charged and those that are controlled to be positively charged are known, and are selected from various types depending on the type and use of the magnetic developer. 1 type, or 2 or more types can be used.

  For controlling the magnetic developer to be negatively charged, for example, an organometallic complex and a chelate compound are effective. Examples thereof include a monoazo metal complex; an acetylacetone metal complex; a metal of an aromatic hydroxycarboxylic acid or an aromatic dicarboxylic acid. A complex or a metal salt. Other examples of controlling the negative developer of the magnetic developer include, for example, aromatic mono- and polycarboxylic acids and metal salts and anhydrides thereof; phenol derivatives such as esters and bisphenols; and monomers containing sulfonic acid groups And sulfur-containing resin as a component.

  Examples of controlling the magnetic developer to be positively charged include, for example, modified products of nigrosine and fatty acid metal salts, and the like; tributylbenzylammonium-1-hydroxy-4-naphthosulfonate, tetrabutylammonium tetrafluoroborate and the like. Onium salts such as quaternary ammonium salts and analogs thereof, such as phosphonium salts, and lake pigments thereof; triphenylmethane dyes and lake pigments thereof (as rake agents, phosphotungstic acid, phosphomolybdic acid, phosphotungsten molybdenum) Acid, tannic acid, lauric acid, gallic acid, ferricyanic acid, ferrocyanic compound, etc.); metal salts of higher fatty acids; diorganotin oxides such as dibutyltin oxide, dioctyltin oxide, dicyclohexyltin oxide; DOO, dioctyl tin borate, diorgano tin borate such as dicyclohexyl tin borate; and the like. In the present invention, these can be used alone or in combination. Among them, a charge control agent such as a nigrosine compound or a quaternary ammonium salt is particularly preferably used for controlling the magnetic developer to be positively charged.

  The magnetic developer used in the present invention can be used by externally adding various materials according to the type of magnetic developer to the magnetic developer particles described above. Examples of the externally added material include a fluidity improver that improves the fluidity of the magnetic developer, such as inorganic fine powder, and a magnetic developer that adjusts the chargeability of the magnetic developer, such as metal oxide fine particles. External additives such as conductive fine powders can be mentioned.

  As the fluidity improver, one that can improve the fluidity of the magnetic developer by externally adding to the magnetic developer particles is used. Examples of such fluidity improvers include fluorine resin powders such as fine vinylidene fluoride powder and polytetrafluoroethylene fine powder; fine powder silica such as wet process silica and dry process silica, fine powder titanium oxide, and fine powder. Alumina; treated silica, surface treated with silane coupling agent, titanium coupling agent, silicone oil, etc., treated titanium oxide, treated alumina; and the like.

The fluidity improver preferably has a specific surface area by nitrogen adsorption measured by the BET method of 30 m ² / g or more, and more preferably 50 m ² / g or more. Although a fluidity improver changes with kinds of fluidity improver, it is preferable to mix | blend 0.01 mass part-8 mass parts with respect to 100 mass parts of magnetic developer particles, for example, 0.1 mass part-4 parts. It is more preferable to blend parts by mass.

  The production method of the magnetic developer used in the present invention is not particularly limited. However, the binder resin for toner and the magnetic material described above, and other additives that are further added as necessary, are added to the Henschel mixer and the ball mill. Mix well with such a mixer, melt, knead and knead using a heat kneader such as a kneader or extruder to make the resins compatible with each other, then cool and solidify the resulting melt kneaded product, The solidified product is pulverized, and the pulverized product is classified to obtain magnetic developer particles. The magnetic developer particles and an external additive such as a fluidity improver are sufficiently mixed as necessary with a mixer such as a Henschel mixer. Can be obtained.

  In the production of the magnetic developer, the classification can be performed at any time after the magnetic developer particles are generated. For example, the classification may be performed after mixing with the external additive. Further, an appropriate impact such as mechanical or thermal may be applied to the generated magnetic developer particles, and the particle shape of the magnetic developer particles may be controlled (more specifically, spherical).

  In the production of the magnetic developer, a method of applying a mechanical impact force is preferable as a method of pulverizing the solidified product. Examples of the treatment that gives mechanical impact force include a method using a mechanical pulverizer such as a pulverizer KTM manufactured by Kawasaki Heavy Industries, Ltd., a turbo mill manufactured by Turbo Industrial Co., Ltd., a mechano-fusion system manufactured by Hosokawa Micron Corporation, The method of processing with apparatuses, such as a manufactured hybridization system, is mentioned. These apparatuses can be used as they are or after being appropriately improved.

  The magnetic developer used in the present invention preferably has a weight average particle diameter (D4) of 5.0 μm to 8.0 μm from the viewpoint of resolution and halftone reproducibility. If the weight average particle diameter of the magnetic developer is less than 4 μm, the magnetic developer is significantly aggregated, which may cause a problem in handling. Further, when the weight average particle diameter of the magnetic developer exceeds 10 μm, the reproduction of dot latent images or fine lines of 100 μm or less may be insufficient.

  The weight average particle size of the magnetic developer can be determined from the result of measuring the particle size distribution using a Coulter Counter TA-II type or Coulter Multisizer (manufactured by Beckman Coulter, Inc.) as a measuring device. In the measurement of the particle size distribution using the measuring device, a 1% NaCl aqueous solution is used as the electrolytic solution. For this electrolytic solution, an aqueous solution prepared using primary sodium chloride, for example, ISOTONR-II (manufactured by Coulter Scientific Japan) can be used.

  As a specific method for measuring the particle size distribution, a surfactant, preferably 0.1 to 5 ml of an alkylbenzene sulfonate is added as a dispersant to the electrolyte solution of 100 to 150 ml, and a magnetic developer as a measurement sample. Of 2 mg to 20 mg. The electrolytic solution to which the magnetic developer has been added is subjected to a dispersion treatment for about 1 to 3 minutes with an ultrasonic disperser, and the volume and number of magnetic developers of 2 μm or more using the 100 μm aperture as the aperture by the measuring device. And volume distribution and number distribution are calculated. From the volume distribution, the weight average particle diameter is obtained using the median value of each channel as a representative value. The weight average particle diameter of the magnetic developer can be adjusted by classification, mixing of classified products, or the like.

  EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited to these Examples.

[Developer production example]
(Developer Production Example 1)
Hybrid resin 100 parts by mass (bisphenol A propylene oxide adduct, bisphenol A ethylene oxide adduct, terephthalic acid, succinic acid derivative, trimellitic acid, styrene, 2-ethylhexyl acrylate, acrylic acid; glass transition temperature: 58 ° C., softening point : 130 ° C, acid value: 12mgKOH / g)
90 parts by mass of magnetic iron oxide (average particle size: 0.18 μm, Hc: 9.6 kA / m, σs: 81 Am ² / kg, σr: 13 Am ² / kg)
Sulfur-containing resin (negatively chargeable charge control resin) 5 parts by mass polyethylene wax (melting point 105 ° C.) 5 parts by mass The above mixture is melt-kneaded with a biaxial extruder heated to 130 ° C., and the melt-kneaded mixture is cooled. The cooled mixture was coarsely pulverized with a hammer mill. The coarsely pulverized product was finely pulverized with a turbo mill (manufactured by Turbo Kogyo Co., Ltd.), and the obtained finely pulverized product was classified with an air classifier to obtain a magnetic developer having a weight average particle diameter of 7.8 μm.

To 100 parts by mass of this toner, 1.0 part by mass of hydrophobic dry silica (BET 180 m ² / g) was externally added using a Henschel mixer to obtain Developer Production Example 1.

(Developer Production Example 2)
100 parts by mass of polyester resin (bisphenol A propylene oxide adduct, bisphenol A ethylene oxide adduct, terephthalic acid, succinic acid derivative, trimellitic acid condensation polymer, glass transition temperature: 60 ° C., softening point: 140 ° C., acid value : 18mgKOH / g)
90 parts by mass of magnetic iron oxide (average particle size: 0.18 μm, Hc: 9.6 kA / m, σs: 81 Am ² / kg, σr: 13 Am ² / kg)
Azo-based iron complex compound (negatively chargeable charge control resin) 2 parts by mass polyethylene wax (melting point 105 ° C.) 5 parts by mass The above mixture was melt-kneaded with a biaxial extruder heated to 130 ° C. After cooling, the cooled mixture was coarsely ground with a hammer mill. The coarsely pulverized product was finely pulverized with a jet mill (manufactured by Nippon Pneumatic Industry Co., Ltd.), and the obtained finely pulverized product was classified with an air classifier to obtain a magnetic developer having a weight average particle diameter of 7.2 μm.

To 100 parts by mass of this toner, 1.0 part by mass of hydrophobic dry silica (BET 180 m ² / g) was externally added using a Henschel mixer to obtain Developer Production Example 2.

[Example of developer carrier production]
(Developer carrier production example H1)
As conductive spherical particles, coal-based bulk mesophase pitch powder 14 having a volume average particle size of 2 μm or less using 100% by mass of spherical phenol resin particles having a volume average particle size of 7.8 μm using a lycra machine (automatic mortar, manufactured by Ishikawa Kogyo). Spherical conductive with a volume average particle size of 5.0 μm obtained by uniformly covering a mass part, graphitizing by heat stabilization at 280 ° C. in air, and then baking at 2000 ° C. in a nitrogen atmosphere, followed by classification. Carbon particles were used.

Conductive carbon black 20 parts by mass Volume average particle size 5.4 μm graphite 80 parts by mass Phenol resin solution produced using ammonia as a catalyst (containing 50% methanol) 300 parts by mass Quaternary ammonium salt compound (1) 30 parts by mass Spherical Carbon particles (volume average particle size 5.0 μm) 30 parts by mass Methanol 160 parts by mass The above material is subjected to sand mill dispersion for 3 hours with φ2 mm zirconia particles, and then the zirconia particles are separated by sieving, and the solid content is 40% with methanol. Coating liquid (c (carbon) / GF (graphite) / B (binder resin) / P (quaternary ammonium salt compound) / R (spherical particle) = 0.2 / 0.8 / 1.5 /0.3/0.3). This coating solution is coated and dried by spraying a PET sheet having a thickness of 100 μm around the surface of a φ32 Al cylinder, and then heated and cured by a hot air drier at 150 ° C./30 minutes to obtain a dynamic friction coefficient and A sample for measuring volume resistivity was prepared.

Using the above-described method, the toner of Development Production Example 1 is printed on ordinary black copier paper (75 g / m ² ) on a standard black-and-white copying machine GP405 manufactured by Canon, with a solid black (toner development amount on paper of 8 g / m ² to An unfixed image (set to 9 g / m ² ) was produced. This was subjected to pressureless fixing for 30 minutes in an atmosphere of 150 ° C. to produce a developer fixing piece for measuring the dynamic friction coefficient, and the dynamic friction coefficient was measured. The load was 0.93 at a load of 0.49 N and 0.32 at a load of 0.98 N.

  Moreover, when the volume resistance was measured by the above-mentioned method, it was 0.23 ohm * cm.

  This paint was sprayed to form a 15 μm film on an Al cylinder having a diameter of 20 mm, and then heated and cured at 150 ° C./30 minutes with a hot air drier to produce a developer carrier H1. Ra of the surface of the conductive coating layer on the developer carrying member is surf coder SE-3500 (manufactured by Kosaka Laboratory), with a cutoff of 0.8 mm, an evaluation length of 4 mm, and a feed rate of 0.5 mm / s. Measurement was performed for 3 points in the axial direction × 3 points in the circumferential direction = 9 points, and the average value thereof was Ra = 0.80 μm.

(Developer carrier production example H2)
Conductive carbon black 20 parts by mass Volume average particle size 5.4 μm graphite 80 parts by mass A phenol resin solution prepared using ammonia as a catalyst (containing 50% methanol) 500 parts by mass Quaternary ammonium salt compound (2) 50 parts by mass Spherical Carbon particles (volume average particle size 5.0 μm) 30 parts by mass Methanol 180 parts by mass The above materials were applied in the same manner as in the developer carrier production example H1, and the coating liquid (c (carbon) / GF (graphite) / B ( Binder resin) / P (quaternary ammonium salt compound) / R (spherical particles) = 0.2 / 0.8 / 2.5 / 0.5 / 0.3). The dynamic friction coefficient of this was measured in the same manner as in Developer Carrier Production Example H1, and it was 1.45 at a load of 0.49 N and 0.44 at a load of 0.98 N.

  Further, when the volume resistance was measured by the above-mentioned method, it was 1.71 Ω · cm.

  Further, a developer carrier H2 was produced in the same manner. At this time, Ra on the surface of the conductive coating layer on the developer carrying member was Ra = 0.55 μm.

(Developer carrier production example H3)
Conductive carbon black 20 parts by mass Volume average particle size 5.4 μm graphite 80 parts by mass Phenol resin solution produced using ammonia as a catalyst (containing 50% methanol) 200 parts by mass Quaternary ammonium salt compound (3) 20 parts by mass Spherical Carbon particles (volume average particle size 5.0 μm) 30 parts by mass Methanol 150 parts by mass The above materials were applied in the same manner as in the developer carrier production example H1, and the coating liquid (c (carbon) / GF (graphite) / B ( Binder resin) / P (quaternary ammonium salt compound) / R (spherical particles) = 0.2 / 0.8 / 1.0 / 0.2 / 0.3). The dynamic friction coefficient of this was measured in the same manner as in Developer Carrier Production Example H1, and found to be 0.81 at a load of 0.49 N and 0.27 at a load of 0.98 N.

  Moreover, when the volume resistance was measured by the above-mentioned method, it was 0.12 Ω · cm.

  Further, a developer carrier H3 was produced by the same operation. At this time, Ra on the surface of the conductive coating layer on the developer carrying member was Ra = 0.83 μm.

(Developer carrier production example H4)
Conductive carbon black 20 parts by mass Graphite with a volume average particle size of 5.4 μm 80 parts by mass A phenol resin solution produced using ammonia as a catalyst (containing 50% methanol) 200 parts by mass Methanol 100 parts by mass A coating solution (c (carbon) / GF (graphite) / B (binder resin) = 0.2 / 0.8 / 1.0) was obtained in the same manner as in Example H1. The dynamic friction coefficient of this was measured in the same manner as in Developer Carrier Production Example H1, and it was 0.76 when the load was 0.49 N and 0.24 when the load was 0.98 N.

  Further, when the volume resistance was measured by the above-mentioned method, it was 0.35 Ω · cm.

  Further, a developer carrier H4 was produced by the same operation. At this time, Ra on the surface of the conductive coating layer on the developer carrying member was Ra = 0.51 μm.

(Developer carrier production example H5)
Conductive carbon black 20 parts by mass Volume average particle size 5.4 μm graphite 80 parts by mass A phenol resin solution produced using ammonia as a catalyst (containing 50% methanol) 600 parts by mass Methanol 100 parts by mass A coating solution (c (carbon) / GF (graphite) / B (binder resin) = 0.2 / 0.8 / 3.0) was obtained in the same manner as in Example H1. When the dynamic friction coefficient of this was measured in the same manner as in Developer Carrier Production Example H1, it was 1.22 at a load of 0.49 N and 0.39 at a load of 0.98 N.

  Moreover, when the volume resistance was measured by the above-mentioned method, it was 8.21 ohm * cm.

  Further, a developer carrier H5 was produced by the same operation. At this time, Ra on the surface of the conductive coating layer on the developer carrying member was Ra = 0.85 μm.

(Developer carrier production example H6)
Conductive carbon black 30 parts by mass Volume average particle size 5.4 μm Graphite 70 parts by mass Urethane resin solution (containing 70% methanol) 500 parts by mass Quaternary ammonium salt compound (1) 30 parts by mass Spherical carbon particles (volume average particle size 5.0 μm) 10 parts by mass Methanol 327 parts by mass The above materials were applied in the same manner as in Developer Carrier Production Example H1, and the coating liquid (c (carbon) / GF (graphite) / B (binder resin) / P ( Quaternary ammonium salt compound) / R (spherical particles) = 0.3 / 0.7 / 1.5 / 0.3 / 0.1) was obtained. The dynamic friction coefficient of this was measured in the same manner as in Developer Carrier Production Example H1, and it was 0.39 at a load of 0.49 N and 0.21 at a load of 0.98 N.

  Further, when the volume resistance was measured by the above-mentioned method, it was 0.55 Ω · cm.

  Further, a developer carrier H6 was produced by the same operation. At this time, the Ra on the surface of the conductive coating layer on the developer carrying member was Ra = 0.82 μm.

(Developer carrier production example H7)
Conductive carbon black 40 parts by mass volume average particle size 5.4 μm graphite 60 parts by mass polyamide resin solution (containing 80% methanol) 750 parts by mass quaternary ammonium salt compound (1) 30 parts by mass spherical carbon particles (volume average particle size 5.0 μm) 10 parts by mass Methanol 560 parts by mass The above materials were applied in the same manner as in the developer carrier production example H1, and the coating liquid (c (carbon) / GF (graphite) / B (binder resin) / P ( Quaternary ammonium salt compound) / R (spherical particles) = 0.4 / 0.6 / 1.5 / 0.3 / 0.1) was obtained. The dynamic friction coefficient of this was measured in the same manner as in Developer Carrier Production Example H1, and it was 0.52 at a load of 0.49 N and 0.24 at a load of 0.98 N.

  Further, when the volume resistance was measured by the above-mentioned method, it was 1.64 Ω · cm.

  Further, a developer carrier H7 was produced by the same operation. The Ra on the surface of the conductive coating layer on the developer carrier at this time was Ra = 0.88 μm.

(Developer carrier production example B1)
As conductive spherical particles, coal-based bulk mesophase pitch powder 14 having a volume average particle diameter of 2 μm or less using a raikai machine (automatic mortar, manufactured by Ishikawa Kogyo Co., Ltd.) on 100 parts by mass of spherical phenol resin particles having a volume average particle diameter of 5.8 μm. Spherical conductive with a volume average particle size of 3.0 μm obtained by uniformly coating a mass part, graphitizing by heating at 280 ° C. in air and then firing at 2000 ° C. in a nitrogen atmosphere, followed by classification. Carbon particles were used.
Conductive carbon black 10 parts by mass Volume average particle size 5.4 μm graphite 90 parts by mass Phenol resin solution produced using ammonia as a catalyst (containing 50% methanol) 300 parts by mass Quaternary ammonium salt compound (1) 15 parts by mass Spherical Carbon particles (volume average particle size 3.0 μm) 15 parts by weight Methanol 130 parts by weight The above materials were applied in the same manner as in the developer carrier production example H1, and the coating liquid (c (carbon) / GF (graphite) / B (condensed) Adhesive resin) / P (quaternary ammonium salt compound) / R (spherical particle) = 0.1 / 0.9 / 1.5 / 0.15 / 0.15), and also the dynamic friction coefficient and volume resistance A sample for rate measurement was prepared. Then, using the toner of Development Production Example 2, a developer fixing piece for measuring the dynamic friction coefficient was prepared in the same manner as in Developer Carrier Production Example H1, and the dynamic friction coefficient was measured. The load was 0.85 at a load of 0.49N and 0.28 at a load of 0.98N.

  Further, when the volume resistance was measured by the above-mentioned method, it was 0.34 Ω · cm.

  Further, a developer carrier B1 was produced in the same manner. At this time, Ra on the surface of the conductive coating layer on the developer carrying member was Ra = 0.85 μm.

(Developer carrier production example B2)
Conductive carbon black 10 parts by mass Volume average particle size 5.4 μm graphite 90 parts by mass Phenol resin solution produced using ammonia as a catalyst (containing 50% methanol) 500 parts by mass Quaternary ammonium salt compound (2) 25 parts by mass Spherical Carbon particles (volume average particle size 3.0 μm) 15 parts by mass Methanol 140 parts by mass The above materials were applied in the same manner as in the developer carrier production example B1, and the coating liquid (c (carbon) / GF (graphite) / B ( Binder resin) / P (quaternary ammonium salt compound) / R (spherical particles) = 0.1 / 0.9 / 2.5 / 0.25 / 0.15). The dynamic friction coefficient of this was measured in the same manner as in Developer Carrier Production Example B1, and it was 1.32 at a load of 0.49 N and 0.34 at a load of 0.98 N.

  Further, when the volume resistance was measured by the above-mentioned method, it was 1.93 Ω · cm.

  Further, a developer carrier B2 was produced in the same manner. At this time, Ra on the surface of the conductive coating layer on the developer carrying member B was Ra = 0.67 μm.

(Developer carrier production example B3)
Conductive carbon black 10 parts by mass Graphite with a volume average particle size of 5.4 μm 90 parts by mass Phenol resin solution prepared using ammonia as a catalyst (containing 50% methanol) 200 parts by mass Quaternary ammonium salt compound (3) 10 parts by mass Spherical Carbon particles (volume average particle size: 3.0 μm) 15 parts by mass Methanol 125 parts by mass The above materials were applied in the same manner as in the developer carrier B Production Example B1, and the coating liquid (c (carbon) / GF (graphite) / B (Binder resin) / P (quaternary ammonium salt compound) / R (spherical particle) = 0.1 / 0.9 / 1.0 / 0.1 / 0.15) was obtained. When the dynamic friction coefficient of this was measured in the same manner as in Developer Carrier Production Example B1, it was 0.76 at a load of 0.49 N and 0.21 at a load of 0.98 N.

  Moreover, when the volume resistance was measured by the above-mentioned method, it was 0.23 ohm * cm.

  Further, a developer carrier B3 was produced by the same operation. The Ra on the surface of the conductive coating layer on the developer carrier at this time was Ra = 0.89 μm.

(Developer carrier production example B4)
Conductive carbon black 10 parts by mass Graphite with a volume average particle size of 5.4 μm 90 parts by mass Phenol resin solution produced using ammonia as a catalyst (containing 50% methanol) 200 parts by mass Methanol 100 parts by mass A coating solution (c (carbon) / GF (graphite) / B (binder resin) = 0.1 / 0.9 / 1.0) was obtained in the same manner as in Example B1. The dynamic friction coefficient of this was measured in the same manner as in Developer Carrier Production Example B1, and it was 0.55 at a load of 0.49 N and 0.19 at a load of 0.98 N.

  Moreover, when the volume resistance was measured by the above-mentioned method, it was 0.47 ohm * cm.

  Further, a developer carrier B4 was produced by the same operation. At this time, the Ra on the surface of the conductive coating layer on the developer carrying member was Ra = 0.64 μm.

(Developer carrier production example B5)
Conductive carbon black 10 parts by mass Graphite with a volume average particle size of 5.4 μm 90 parts by mass Phenol resin solution produced using ammonia as a catalyst (containing 50% methanol) 600 parts by mass Methanol 100 parts by mass A coating solution (c (carbon) / GF (graphite) / B (binder resin) = 0.1 / 0.9 / 3.0) was obtained in the same manner as in Example B1. The dynamic friction coefficient of this was measured in the same manner as in Developer Carrier Production Example B1, and it was 1.07 when the load was 0.49 N and 0.27 when the load was 0.98 N.

  Further, when the volume resistance was measured by the above-mentioned method, it was 9.67 Ω · cm.

  Further, a developer carrier B5 was produced by the same operation. At this time, Ra on the surface of the conductive coating layer on the developer carrying member was Ra = 0.91 μm.

(Developer carrier production example B6)
Conductive carbon black 20 parts by mass volume average particle size 5.4 μm graphite 80 parts by mass urethane resin solution (containing 70% methanol) 500 parts by mass quaternary ammonium salt compound (1) 15 parts by mass spherical carbon particles (volume average particle size 3.0 μm) 5 parts by mass Methanol 280 parts by mass The above materials were applied in the same manner as in the developer carrier production example B1, and the coating liquid (c (carbon) / GF (graphite) / B (binder resin) / P ( Quaternary ammonium salt compound) / R (spherical particles) = 0.2 / 0.8 / 1.5 / 0.15 / 0.05). When the dynamic friction coefficient of this was measured in the same manner as in Developer Carrier Production Example B1, it was 0.31 at a load of 0.49 N and 0.21 at a load of 0.98 N.

  Moreover, when the volume resistance was measured by the above-mentioned method, it was 0.78 ohm * cm.

  Further, a developer carrier B6 was produced by the same operation. The Ra on the surface of the conductive coating layer on the developer carrier at this time was Ra = 0.89 μm.

(Developer carrier production example B7)
Conductive carbon black 30 parts by mass volume average particle size 5.4 μm graphite 70 parts by mass polyamide resin solution (containing 80% methanol) 750 parts by mass quaternary ammonium salt compound (1) 15 parts by mass spherical carbon particles (volume average particle size 5.0 μm) 5 parts by mass Methanol 480 parts by mass The above materials were applied in the same manner as in the developer carrier production example B1, and the coating liquid (c (carbon) / GF (graphite) / B (binder resin) / P ( Quaternary ammonium salt compound) / R (spherical particles) = 0.3 / 0.7 / 1.5 / 0.15 / 0.05). When the dynamic friction coefficient of this was measured in the same manner as in Developer Carrier Production Example B1, it was 0.44 at a load of 0.49 N and 0.20 at a load of 0.98 N.

  Further, when the volume resistance was measured by the above-mentioned method, it was 1.79 Ω · cm.

  Further, a developer carrier B7 was produced by the same operation. At this time, Ra on the surface of the conductive coating layer on the developer carrying member was Ra = 0.92 μm.

(Comparative developer carrier production example 1)
An Al sheet having a thickness of 100 μm was wound around the surface of a φ32 Al cylinder, which was sandblasted with FGB # 100 to prepare a sample for measuring the dynamic friction coefficient. When the dynamic friction coefficient of this was measured in the same manner as in Developer Carrier Production Example H1, it was 4.20 at a load of 0.49 N and 1.40 at a load of 0.98 N.

  Further, the surface of an Al cylinder having a diameter of 20 mm was similarly sandblasted with FGB # 100, and this was designated as Comparative Developer Carrier Example 1. At this time, Ra on the developer carrying member was Ra = 1.24 μm.

(Comparative developer carrier production example 2)
Conductive carbon black 20 parts by mass Volume average particle size 5.4 μm graphite 80 parts by mass Phenol resin solution produced using ammonia as a catalyst (containing 50% methanol) 2000 parts by mass Methanol 100 parts by mass A coating solution (c (carbon) / GF (graphite) / B (binder resin) = 0.2 / 0.8 / 10.0) was obtained in the same manner as in Example H1. The dynamic friction coefficient was measured in the same manner as in Developer Carrier Production Example 1 and found to be 2.50 at a load of 0.49 N and 0.84 at a load of 0.98 N.

  Further, when the volume resistance was measured by the above-mentioned method, it was 15.4 Ω · cm.

  Further, a comparative developer carrier 2 was produced by the same operation. The Ra on the surface of the conductive coating layer on the developer carrying member at this time was Ra = 0.43 μm.

(Comparative developer carrier production example 3)
Conductive carbon black 40 mass parts Graphite with a volume average particle size of 5.4 μm 160 mass parts Phenol resin solution produced using ammonia as a catalyst (containing 50% methanol) 2000 mass parts Methanol 200 mass parts The above materials are produced as a developer carrier A coating solution (c (carbon) / GF (graphite) / B (binder resin) = 0.4 / 1.6 / 1.0) was obtained in the same manner as in Example H1. As in developer carrier production example H1, a 100 μm thick PET sheet is wrapped around the surface of a φ32 Al cylinder, sprayed, dried, and then polished with the surface polishing apparatus shown in FIG. Was given. As shown in the figure, the developer carrier 507 is rotated in the direction of the arrow. A surface of the developing roller 507 was polished by rubbing a belt-like felt 523 fixed to a holder (not shown) under a pressing load. The pressing load at this time was 39.2N. The samples for measuring the dynamic friction coefficient and the volume resistivity thus prepared were measured for the dynamic friction coefficient in the same manner as in the developer carrier production example H1, and when the load was 0.49 N, the load was 0.14, and the load was 0.98 N. 0.09.

  Further, when the volume resistance was measured by the above-mentioned method, it was 0.76 Ω · cm.

  Further, a comparative developer carrier 3 was prepared by the same operation (coating, drying, polishing) as described above. The Ra on the surface of the conductive coating layer on the developer carrier at this time was Ra = 0.89 μm.

  Table 1 summarizes the prescription and physical properties of the resin coating layer of each developer carrier.

<Example A1>
In the developing apparatus shown in FIG. 1, the developer production example 1 and the developer carrier production example H1 were used as a copying machine with a process speed of 230 mm / sec and 30 sheets. Normal temperature and low humidity environment (N / L) (temperature 23 ° C, humidity 5%), normal temperature and normal humidity environment (N / N) (temperature 23 ° C, humidity 60%) and high temperature and high humidity environment (H / H) (30 ° C, 80%), 50,000 sheets were passed through each.

  In the paper passing durability by the image forming apparatus using the developing device, a chart having an image ratio of 5% was used for the document. N / L evaluation results are shown in Table, N / N evaluation results in Table, and H / H evaluation results in Table. The image and developability were evaluated as follows.

(A) Image Density Image density was measured using a Macbeth densitometer (Macbeth Co., Ltd.) using an SPI filter, and a 1.1 mm density 5 mm round reflection density on the original was in the early and middle endurance (when 20,000 images were printed). And after endurance (when 50,000 sheets were printed).

(B) Fog The fog on the image is measured with a reflection densitometer (reflectometer model TC-6DS manufactured by Tokyo Denshoku Co., Ltd.) on the transfer material before image formation and the white background after image formation. The worst value (maximum value) of partial reflection density was Ds (%), the average reflection density of the transfer material before image formation was Dr (%), and (Ds)-(Dr) was determined and evaluated as the fog amount. The measurement was performed at the initial stage of durability, the middle period of durability, and after the durability, and fog was evaluated according to the following criteria.
A: Fog amount is 1.0% or less B: Fog amount is 1.0-2.0% or less C: Fog amount is 2.0-3.0% or less D: Fog amount is 3.0-4.0 % Or less (practical level lower limit)
E: The fog amount exceeds 4.0% (impractical level)

(C) Sleeve ghost After the end of durability, the end of durability, and after endurance, the position of the developer carrying member that developed an image in which the solid white portion and the solid black portion are adjacent to each other comes to the developing position at the next rotation of the developer carrying member, and halftone The image was developed, and the difference in density appearing on the halftone image thus formed was visually observed and evaluated according to the following criteria.
A: No shade difference is observed at all. B: A slight shade difference can be confirmed depending on the viewing angle. C: A shade difference where the edge is not clear can be confirmed, but it is practically OK level.
D: Difference in shading is slightly clear (practical level lower limit)
E: The density difference can be clearly confirmed, and it can be confirmed as the image density difference (impractical level)

(D) Blotch (defective image)
Various images such as solid black, halftone, and line images, and the observation of the toner coat defects on the developer carrier such as wavy unevenness and blotch (spotted unevenness) on the developer carrier at that time Thus, the observation results in the initial durability period, the intermediate durability period and after the durability period were evaluated based on the following criteria.
A: Neither image nor sleeve can be confirmed at all.
B: Although it can be confirmed slightly on the sleeve, it can hardly be confirmed on the image.
C: The first halftone image or solid black image can be confirmed on the first cycle of the sleeve cycle.
D: Can be confirmed with a halftone image or a solid black image (practical level lower limit)
E: An image defect that causes a practical problem in the entire solid black image can be confirmed (impractical level).

(E) Sleeve contamination and fusion with toner (contamination and anti-fusing)
After image evaluation under each environment, the developing sleeve is removed, and the toner on the developing sleeve surface is removed by a vacuum cleaner and an air blow (using an air gun), and an ultra-deep shape measuring microscope (manufactured by KEYENCE: VK-8500) is used. The results of evaluation were shown with the following indices.
A: No toner is present.
B: Toner fine powder is slightly observed in the dent on the sleeve surface.
C: Toner particles remain in the dents on the sleeve, but the original shape of the toner particles remains.
D: Toner particles adhering to the sleeve are present in various places, and the toner particles are crushed as if they are slightly melted. It does not appear on the image. (Practical level lower limit)
E: Toner adhesion is observed on the sleeve surface. Appears on the image (impractical level)
All were very good results.

<Example A2>
Images and developability were evaluated in the same manner as in Example A1, except that Developer Carrier Production Example H2 was used. All were very good results.

<Example A3>
Images and developability were evaluated in the same manner as in Example A1, except that Developer Carrier Production Example H3 was used. All were very good results.

<Example A4>
In Example A1, images and developability were evaluated in the same manner except that Developer Carrier Production Example H4 was used. Although the image density of H / H was slightly low, it was a level with no problem at all. The others were very good results.

<Example A5>
Images and developability were evaluated in the same manner as in Example A1, except that Developer Carrier Production Example H5 was used. N / L fog / sleeve ghost / blotch, N / N 20,000 or more sleeve ghosts, and H / H 20,000 or more sleeves were contaminated and fused at rank B, but there was no problem at all. there were. The others were very good results.

<Example A6>
Images and developability were evaluated in the same manner as in Example A1, except that Developer Carrier Production Example H6 was used. N / L sleeve ghost, blotch, fog after 20,000 sheets, N / N after 20,000 sleeve ghosts, and H / H after 20,000 sleeve contamination / fusion were ranked B. There was no problem at all. The others were very good results.

<Example A7>
Images and developability were evaluated in the same manner as in Example A1, except that Developer Carrier Production Example H7 was used. N / L sleeve ghost, blotch, fog after 20,000 sheets, N / N after 20,000 sleeve ghosts, and H / H after 20,000 sleeve contamination / fusion were ranked B. There was no problem at all. The others were very good results.

<Example B1>
In Example A1, images and developability were evaluated in the same manner except that Developer Production Example 2 and Developer Carrier Production Example B1 were used. N / N and N / L fog, sleeve ghost, blotch, sleeve contamination and fusion were ranked B, but there was no problem at all. The others were very good results.

<Example B2>
In Example A1, images and developability were evaluated in the same manner except that Developer Production Example 2 and Developer Carrier Production Example B2 were used. N / N and N / L fog, sleeve ghost, blotch, sleeve contamination and fusion were ranked B, but there was no problem at all. The others were very good results.

<Example B3>
In Example A1, images and developability were evaluated in the same manner except that Developer Production Example 2 and Developer Carrier Production Example B3 were used. N / N and N / L fog, sleeve ghost, blotch, sleeve contamination and fusion were ranked B, but there was no problem at all. The others were very good results.

<Example B4>
In Example A1, images and developability were evaluated in the same manner except that Developer Production Example 2 and Developer Carrier Production Example B4 were used. The image density of H / H was slightly low, and N / N and N / L fog, sleeve ghost, blotch, sleeve contamination, and fusion were ranked B, but they were at a level with no problem at all. The others were very good results.

<Example B5>
In Example A1, images and developability were evaluated in the same manner except that Developer Production Example 2 and Developer Carrier Production Example B5 were used. N / N fog, sleeve ghost, blotch, sleeve contamination / fusion, N / L sleeve contamination / fusion, and H / H after 20,000 sleeve contamination / fusion, rank B, N / L The fog, sleeve ghost, and blotch were ranked C, but there was no problem. The others were very good results.

<Example B6>
In Example A1, images and developability were evaluated in the same manner except that Developer Production Example 2 and Developer Carrier Production Example B6 were used. N / N fog, initial sleeve ghost, blotch, sleeve contamination / fusion, N / L initial fog / sleeve contamination / fusion, H / H fog, sleeve ghost / blotch, initial sleeve contamination / fusion Is rank B, sleeve ghost after N / N 20,000 sheets, fog / sleeve ghost / blotch after 20,000 sheets N / L, sleeve contamination / fusion after 20,000 sheets H / H is C rank There was no problem. The image density was a good result.

<Example B7>
In Example A1, images and developability were evaluated in the same manner except that Developer Production Example 2 and Developer Carrier Production Example B7 were used. N / N fog, initial sleeve ghost, blotch, sleeve contamination / fusion, N / L initial fog / sleeve contamination / fusion, H / H fog, sleeve ghost / blotch, initial sleeve contamination / fusion Is rank B, sleeve ghost after N / N 20,000 sheets, fog / sleeve ghost / blotch after 20,000 sheets N / L, sleeve contamination / fusion after 20,000 sheets H / H is C rank There was no problem. The image density was a good result.

<Comparative Example 1>
Image evaluation was performed in the same manner as in Example 1 except that Developer Production Example 1 and Comparative Developer Carrier Production Example 1 were used. Since the H / H sleeve contamination / fusion was at the NG level from the beginning, the H / H was interrupted only at the initial stage. This is because the coefficient of dynamic friction according to the present invention of Comparative Developer Carrier Production Example 1 is large, so that the developer pumped up by the rotary agitating member 6 is difficult to separate from the developer carrier 1, and as a result, the developer regulating member 11. This is considered to be because the toner was fused on the developer carrier 1 by rubbing against the rotating stirring member 6.

  Moreover, the ghost and blotch in N / L were NG level from the beginning. The fog was bad from the beginning for both N / N and N / L. Durability and fogging are improved because the image density is reduced.

<Comparative example 2>
Image evaluation was performed in the same manner as in Example 1 except that Developer Production Example 1 and Comparative Developer Carrier Production Example 2 were used. The initial stage of H / H sleeve contamination / fusion was at a practical level, but after 20,000 sheets it was at the NG level, so H / H was interrupted at 20,000 sheets. The coefficient of dynamic friction according to the present invention in Comparative Developer Carrier Production Example 2 was within the proper range when the load was 0.98 N, but exceeded the proper range when the load was 0.49 N. Therefore, although it was barely at a practical level in the initial stage, it is considered that it became NG with durability.

<Comparative Example 3>
Image evaluation was performed in the same manner as in Example 1 except that Developer Production Example 1 and Comparative Developer Carrier Production Example 3 were used. Initial fog, sleeve ghost, blotch and sleeve contamination / fusion were good, but the image density was low in all three environments. This is because the kinetic friction coefficient according to the present invention of Comparative Developer Carrier Production Example 3 was less than the appropriate range, so that the developer pumped up by the rotary stirring member 6 was easily separated from the developer carrier 1, and as a result This is probably because the developer on the agent carrier 1 is insufficient.

  When the surface of the developer carrying member after the endurance of 20,000 sheets was viewed, the resin coating layer was peeled off and the underlying aluminum was exposed. Therefore, the image output durability was interrupted with 20,000 copies.

  Table 2 shows the combinations of developers and developer carriers in the above Examples and Comparative Examples, and Table 3 shows the evaluation results.

It is a figure explaining the developing device of this invention. It is a schematic diagram which shows the conductive resin coating layer on the surface of a developer carrier. It is a figure which shows the outline of the apparatus used by the friction coefficient measurement of an Example. It is a measurement model of the triboelectric charge amount by the gradient method. It is a figure which shows the charge amount of a model negative toner with respect to the addition amount to the resin of a quaternary ammonium salt compound. It is a figure explaining the conventional developing device. It is a typical block diagram of the apparatus which polishes with a felt on the surface of a developer carrier. It is a figure explaining the conventional developing device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,101 Developer carrier 2,102 Image carrier 5,105 Hopper chamber 6,106 Rotating stirring member 11,111 Developer regulating member 12,112 Openable / closable opening for supplying developer 13,113 Developer Supply detection member 14, 114 Developer supply determination device 15, 115 Developer restriction member 103 Development chamber 104 Development chamber stirring member 109 Partition wall 110 Opening portion 201 Resin coating layer 202 Roughening material or reinforcing particles 203 Conductive fine particles 204 Binding Resin 205 Solid lubricant 206 Cylindrical substrate 308 Load cell 309 Developer fixing piece 310 Test piece of developer carrier resin coating layer 311 Weight 312 Moving table 507 Developer carrier 523 Strip-shaped felt

Claims (1)

Magnetic developer,
A container of the magnetic developer;
Is disposed in an opening of the container, by rotating, supplies a magnetic developer of the container to the image bearing member, a developer carrying member having a resin coating layer formed on the surface of the substrate and said substrate When,
A rotating stirring member disposed in the container for stirring the magnetic developer and supplying the magnetic developer to the developer carrying member;
A magnetic developer replenishment detecting means disposed in the container,
In the developing device, the lower end of the developer carrying member is located above the rotation center axis of the rotary stirring member, and the upper end of the replenishment detection means is located below the rotation center axis of the rotation stirring member. A method for evaluating the surface characteristics of a developer carrier used ,
A developer fixing piece for measuring a dynamic friction coefficient, in which a solid black unfixed image formed on plain paper for a copying machine with the magnetic developer was fixed without pressure on the flat surface of the test piece of the resin coating layer, was attached. A surface property of a developer carrying member comprising a step of contacting a 30 mm flat indenter with a load that maintains the shape of the magnetic developer, and sliding the slide at 6000 mm / min to measure a dynamic friction coefficient Evaluation method.

Images