JP4440082B2 - Magnetic carrier and two-component developer - Google Patents

Description

  The present invention relates to a two-component developer used in electrophotography, electrostatic recording method, and electrostatic printing method, and a magnetic carrier constituting the developer.

  Conventionally, in an image forming apparatus using an electrophotographic method such as a printer or a copying machine, a two-component developer containing a toner and a magnetic carrier is suitably used from the viewpoint of image quality, durability, and high-speed compatibility. As a method of developing such a two-component developer, in order to ensure a sufficient image density and improve the reproducibility of fine lines, a magnetic brush of the developer is brought into contact with the photosensitive member, and the peripheral speed of the photosensitive member is adjusted. Thus, a developing method is used in which the peripheral speed of the developing sleeve is increased and the alternating electric field and the DC electric field are superimposed.

  A magnetic carrier used in such a contact two-component development method is required to have a dielectric breakdown resistance with respect to an applied voltage. Therefore, the surface of a magnetic material such as ferrite or magnetite is coated with an insulating resin. However, the carrier is insulated along with the resin coating and does not work as a developing electrode at the time of development, so that an edge effect is produced between the halftone and the solid black, and so-called white defects such as white defects may occur.

  In order to improve this image defect, in order to stabilize the charging to the toner for a long period of time, a proposal has been made to disperse resin fine particles containing conductive powder in a coating material containing a coating resin (for example, patents). Reference 1). Furthermore, a proposal has been made to use resin fine particles and a conductive material dispersed in a resin whose coating material has a critical surface tension of 35 dyne / cm or less (see, for example, Patent Document 2).

  However, the above-described means can suppress image defects and prevent contamination on the carrier surface (spent). However, since the ferrite particles are used for the core particles, the developer magnetic brush is not suitable for contact two-component development. In some cases, unevenness of the stitches is likely to occur, and there is a problem that the toner is deteriorated due to stress on the toner when the low-consumption printing is continued, and the toner is separated from the carrier.

  Therefore, in order to reduce the magnetic force and increase the resistance, proposals have been made to use magnetic fine particle dispersed magnetic carriers (see, for example, Patent Document 3).

  Further, a proposal has been made to prevent toner spent by using a magnetic carrier coated with a resin having an aminosilane coupling agent, a fluoroalkyl unit, or a unit such as a methylene unit on the surface of a magnetic fine particle dispersed core (for example, patents). Reference 4).

These means have high carrier resistivity, prevent image defects such as white spots by counter-rotating the developing sleeve and photoconductor with a relatively low magnetic force carrier, and are excellent in dot reproducibility at high image density. Furthermore, carrier contamination is improved. However, when the process speed is further increased due to further increase in speed, the rubbing force of the developer magnetic brush on the photosensitive member in the development region becomes strong, and the developer may be deteriorated. In addition, the development method in which the developing sleeve and the photosensitive member are rotated counter-rotating is more effective than the developing method in which the developing sleeve and the photosensitive member are rotated in the forward direction. Unevenness (white streaks) may occur easily. Also, the change in the development amount (image density) and the development amount with respect to the gradation of the potential (gamma curve) due to changes in the distance between the development sleeve and the photosensitive member, the alternating electric field strength, the amount of developer carried on the development sleeve, and the like. Is susceptible.
JP-A-10-307429, page 2-4 Special Registration No. 3173374, page 2-6, Table 1 JP-A-9-281807, page 2-8 JP-A-2000-39740, pages 9-15 FIG.

  An object of the present invention is to provide a magnetic carrier and a two-component developer that have solved the above-described problems.

  That is, an object of the present invention is to provide a magnetic carrier and a two-component developer that are free from image defects such as white spots, have a high image density, and are excellent in dot reproducibility.

  A further object of the present invention is to provide a magnetic carrier and a two-component developer capable of maintaining a stable carrier surface over a long period of time with little peeling of the coating material from the magnetic carrier even at elevated temperatures.

  As a result of intensive studies, the inventors of the present invention have found that the magnetic carrier surface is coated with a coating material containing a coating resin on the surface of the magnetic fine particle-dispersed resin core. It has been found that the above requirements can be satisfied by having it, and the present invention has been achieved.

The present invention relates to a two-component developer containing a toner and a magnetic carrier.
The toner has toner particles containing a binder resin, a release agent, and a colorant,
The transmittance of light having a wavelength of 600 nm with respect to a dispersion obtained by dispersing the toner in an aqueous solution of 45% by volume of methanol is 10 to 70%, and the magnetic carrier is a magnetic fine particle dispersed resin core containing at least magnetic fine particles and a binder resin. The surface of the magnetic carrier is coated with a coating material having a coating resin , and the ratio of the surface of the magnetic carrier to the carbon element abundance ratio (Fatom / Catom) of the fluorine element abundance ratio (Fatom) 0.10 to 0.85, which can be theoretically calculated from the ratio (Fatom / Catom) of the fluorine element abundance (Fatom) to the carbon element abundance (Catom) on the surface of the magnetic carrier and the molecular structure of the coating resin. Ratio of fluorine element abundance ratio (Fcalc) to carbon element abundance ratio (Ccalc) ( calc / Ccalc) the ratio of (Fatom / Catom) / (Fcalc / Ccalc) is directed to two-component developer, which is a 1.10 to 2.00.

〔式中、ｍは１乃至２０のいずれかの整数を示す。〕
で示されるパーフルオロアルキルユニットを有するメタクリル酸エステルユニットまたはアクリル酸エステルユニットで構成される重合体又は共重合体である（１）乃至（９）のいずれかに記載の磁性キャリア。

[Wherein, m represents an integer of 1 to 20. ]
The magnetic carrier according to any one of (1) to (9), which is a polymer or copolymer composed of a methacrylic acid ester unit or an acrylic acid ester unit having a perfluoroalkyl unit represented by formula (1).

  In the magnetic carrier formed by coating the surface of the magnetic fine particle-dispersed resin core with a coating material having a coating resin, the present invention in which the surface of the magnetic carrier is defined effectively suppresses image defects such as white spots and has a high image density. With this, an image with excellent dot reproducibility can be obtained.

  White spots will be described with reference to FIG. FIG. 2 shows an enlarged view (2-1) of an image in which an actual white spot is generated, a schematic diagram (2-2) of a cross section of a toner layer that forms an image at that time, and an ideal state (a white spot is shown). (2-3) is shown. (2-1) is a developing method in which the developing sleeve and the photosensitive member are rotated in the forward direction in the developing region and developed, and the developing direction of the toner is developed from the left in the order of the halftone portion, the solid portion, and the halftone portion. It is an image. A portion that is white between the left halftone portion and the solid black portion is referred to as “white spot” in the present invention. (2-2) schematically shows a cross section of the image viewed from the side. In the figure, 21 is a transfer material, and 22 is a toner layer. In FIG. 2, A is a white portion, and the toner layer is lost in the boundary region between the halftone portion and the solid portion. Also, a so-called “sweeping” phenomenon (B in FIG. 2) in which the toner layer becomes higher appears at the boundary between the solid portion and the halftone portion where the development is performed next. Since “white spots” and “sweeping” occur by the same mechanism, the white spots will be described in detail here.

  Image defects such as white spots are caused by the wrapping of lines of electric force from the developing sleeve to the photosensitive member at the developing pole. When the specific resistance of the carrier is low to some extent, the carrier plays the role of an electrode, and the electrode apparently exists in the vicinity of the photoconductor pole, and since the wraparound of the electric lines of force can be suppressed, the edge effect is difficult to appear, Less likely to cause image defects such as white spots. However, when the specific resistance of the carrier is high, an electric field is applied between the photosensitive member and the developing sleeve (several hundred μm), so that the lines of electric force swell around the nearest part. Therefore, at the rear end of the development nip (the part where the developer is in contact with the photoreceptor), when the carrier surface countercharge remains after the toner flies from the carrier by development, and the carrier has a high specific resistance, It was found that white spots occurred due to the developed toner being pulled back by the counter charge. Therefore, white spots can be improved by lowering the specific resistance of the carrier, so that the carrier acts as an electrode, thereby suppressing the wraparound of the electric field lines as much as possible and leaking the residual charge on the carrier surface after development. Turned out to be. However, by using a carrier having a specific resistance, the latent image may be disturbed by rubbing the photosensitive member, and the halftone portion may be scratched. It has also been found that even when a carrier having a high specific resistance is used, if the developing sleeve and the photosensitive member perform development in the counter direction, the carrier after development is instantaneously separated from the developing area, so that the toner is not pulled back. did. However, the circumferential speed difference with respect to the photosensitive member becomes too large, and scavenging by the magnetic brush may occur.

  Further, it has also been found that the white toner is effective in developing a sufficient amount of toner with respect to the latent image potential by eliminating the potential difference between the halftone and the solid image portion, thereby eliminating the wraparound of the lines of electric force. Therefore, developability that sufficiently satisfies the latent image potential is important.

  Therefore, in the magnetic carrier of the present invention, by selectively orienting the fluorine element in the coating material and further controlling the surface presence of the fluorine element on the surface of the magnetic carrier, the release of the toner from the magnetic carrier surface is achieved. As a result, the toner releasability at the time of development is improved, image defects such as white spots are improved, and dot reproducibility is improved, leading to the present invention.

  The present invention is described in detail below.

  In a magnetic carrier obtained by coating the surface of a magnetic fine particle dispersed resin core containing at least magnetic fine particles and a binder resin of the present invention with a coating material having a coating resin, the fluorine element abundance (Fatom) of the surface of the magnetic carrier is The ratio (Fatom / Catom) to the carbon element abundance (Catom) is 0.10 to 0.85. Preferably it is 0.12-0.75, More preferably, it is 0.15-0.65.

  This is because when the ratio of the fluorine element abundance (Fatom) to the carbon element abundance (Catom) (Fatom / Catom) is within the above range, the surface of the magnetic carrier coated with a coating material. Since the surface energy of the surface of the magnetic carrier is reduced, the releasability of the toner from the surface of the magnetic carrier can be controlled. As a result, the toner releasability during development can be controlled. To improve image defects such as white spots.

  When the ratio (Fatom / Catom) is less than 0.10, the effect of releasing the toner from the surface of the magnetic carrier is hardly exhibited, the toner separation property is deteriorated, and image defects such as white spots are likely to occur.

  When the ratio (Fatom / Catom) exceeds 0.85, the release effect of the toner from the magnetic carrier surface is improved, and the toner separation is improved, but the toner is easily unstable and the dot reproducibility is improved. It deteriorates and environmental stability is poor and is not preferable.

  As a method for controlling the surface abundance ratio of elemental fluorine, in the magnetic carrier coating process, the carrier core and coating material mixing process, the drying process and / or the cooling process are controlled, and the fluorine element is selectively applied to the surface of the magnetic carrier. It can be oriented to increase the abundance of fluorine element on the surface. Specifically, it is preferable that the drying step and / or the cooling step be performed under conditions with a small absolute water content in the atmospheric environment. This is because, since the carrier core is hydrophilic, the hydrophilic component in the coating resin contained in the coating material is selectively oriented on the surface of the carrier core, and conversely, the hydrophobic fluorine element monomer is on the surface of the magnetic carrier. It is thought to be oriented.

  In the present invention, the coating material is characterized by having a selective fluorine element distribution with respect to the surface of the magnetic carrier rather than the surface of the carrier core. The releasability from the surface of the magnetic carrier can be improved.

  The present invention also compares the fluorine abundance ratio to the carbon element abundance ratio, which can be theoretically calculated from the molecular structure of the coating resin contained in the coating material, and the ratio of the fluorine element abundance ratio on the actual magnetic carrier surface to the carbon element abundance ratio. By doing so, it can be confirmed that it is selectively oriented.

  Therefore, the ratio (Fcalc / Ccalc) of the fluorine element abundance ratio (Fcalc) to the carbon element abundance ratio (Ccalc), which can be calculated from the molecular structure of the coating resin used in the present invention, is 0.05 to 0.75. preferable. If it is less than 0.05, the release effect due to the fluorine element is difficult to be exhibited, and if it exceeds 0.75, the release effect is increased, but the release property with the carrier core is increased, and the adhesion to the carrier core is reduced. , The peel resistance from the carrier core is deteriorated. Further, the durability of the surface of the magnetic carrier formed by coating with the coating material is deteriorated, and the charge imparting property is lowered.

  Furthermore, in the present invention, the fluorine element abundance ratio (Fatom / Catom) of the fluorine element abundance ratio (Fatom) on the surface of the magnetic carrier to the carbon element abundance ratio (Catom) and the molecular structure of the coat resin can be calculated theoretically ( The ratio (Fatom / Catom) / (Fcalc / Ccalc) to the ratio of Fcalc) to the carbon element abundance (Catom) (Fcalc / Ccalc) is 1.01 to 3.00. Preferably, it is 1.10 to 2.00, and more preferably 1.20 to 1.80.

  When the ratio (Fatom / Catom) / (Fcalc / Ccalc) is within the above range, it means that the fluorine element is selectively oriented on the surface of the magnetic carrier in the coating material. In this case, since the hydrophilic component in the coating material is selectively oriented on the surface of the carrier core, the peel resistance from the carrier core can be improved. Further, since the fluorine element is selectively oriented on the surface of the carrier, the releasability of the toner from the surface of the magnetic carrier can be improved. In this way, it is possible to develop peel resistance due to increased adhesion to the carrier core and release properties on the surface of the magnetic carrier, making it possible to satisfy both conflicting characteristics. It was. In particular, the case of 1.10 to 2.00 is preferable because it has durability stability even when applied to a high-speed machine having a high process speed.

  When the ratio (Fatom / Catom) / (Fcalc / Ccalc) is less than 1.01, selective orientation is not performed, and when it exceeds 3.00, fluorine element is oriented too much. As a result, the durability of the surface of the magnetic carrier deteriorates.

The specific resistance of the magnetic carrier of the present invention is preferably 1 × 10 ^{7 to} 1 × 10 ¹¹ (Ω · cm). It has been found that when the specific resistance of the magnetic carrier of the present invention is within the above range, there is no image defect such as white spots, and an image with high image density and excellent dot reproducibility can be provided.

  This is because, by setting the specific resistance of the magnetic carrier within the above range, the electrode effect on the developing sleeve is alleviated, and by controlling the fluorine element abundance on the surface of the magnetic carrier, the toner from the magnetic carrier The separation is improved. By doing so, the developability of the toner with respect to the latent image potential can be improved. As a result, it is possible to achieve both of eliminating image defects such as white spots and improving dot reproducibility, which have been difficult in the past.

When the specific resistance of the magnetic carrier is less than 1 × 10 ⁷ (Ω · cm), the white spots are improved, but the latent image of the minute dots is disturbed and the halftone reproducibility may be deteriorated. is there. Further, when the specific resistance of the magnetic carrier exceeds 1 × 10 ¹¹ (Ω · cm), white spots are deteriorated, and developability sufficiently satisfying the latent image potential cannot be obtained, and the image is deteriorated. There is a case.

In addition, the specific surface area BET1 (m ² / g) according to the BET method of the magnetic carrier used in the present invention is preferably 0.02 to 0.20 (m ² / g).

When the specific surface area BET1 (m ² / g) of the magnetic carrier by the BET method is within the above range, contamination of the toner and additives used in the toner can be prevented, and toner from the surface of the magnetic carrier can be prevented. Separation can be improved.

When the specific surface area BET1 (m ² / g) is less than 0.02 (m ² / g), the specific surface area is too small for the toner, so the contact area between the toner and the magnetic carrier surface is too small. The charge imparting ability may be deteriorated.

When the specific surface area BET1 (m ² / g) exceeds 0.20 (m ² / g), the contact area of the toner on the magnetic carrier becomes too large, the separation of the toner from the surface of the magnetic carrier deteriorates, and white spots such as white spots appear. May cause layer defects. Further, the uneven surface property of the carrier may cause uneven stress in durability and may promote contamination of the toner and additives used in the toner.

  The magnetic carrier of the present invention can increase the abundance of fluorine element by using a coating resin having a high fluorine element content in advance in order to increase the abundance of fluorine element on the surface of the magnetic carrier. The carrier core is preferably the following in order to achieve both the peel resistance of the coating resin.

The specific surface area BET2 (m ² / g) by the BET method of the magnetic fine particle dispersed resin core used as the carrier core of the magnetic carrier of the present invention is preferably 0.02 to 0.20 (m ² / g).

When the magnetic fine particle-dispersed resin core used in the present invention has a specific surface area BET2 (m ² / g) within the above range, the adhesion of the coating material to the surface of the carrier core is increased, and the coating material is resistant to peeling during durability. Even when the stress is increased, such as when the temperature is increased, a stable carrier surface can be maintained. Therefore, a stable chargeability can be imparted, and a stable image density image can be maintained over a long period of time.

When the specific surface area BET2 (m ² / g) is less than 0.02 (m ² / g), when the coating material is coated on the core surface, the coating thickness becomes excessive and the carriers are united with each other. Applicability deteriorates.

When the specific surface area BET2 (m ² / g) exceeds 0.20 (m ² / g), the adhesive force between the core surface and the coating material increases, but conversely, the carrier coated with the influence of the surface property of the core. The surface property of the toner is affected, the stress in durability and the like is not uniform, and the contamination of the toner and additives used in the toner may be promoted.

  The specific surface area BET1 is 0.02 to 0.19, the specific surface area BET2 is 0.03 to 0.20, and the specific surface area BET1 and the specific surface area BET2 satisfy BET1 <BET2. preferable.

  In addition, when the specific surface area BET1 and the specific surface area BET2 are within the above ranges, the surface stability when the carrier core is coated with a coating material is increased, and the durability stability is improved without contamination of the toner and additives. To do. Furthermore, even when applied to a high-speed machine with increased process speed, it has durability stability.

  In the case of BET1> BET2, the specific surface area becomes larger than the surface of the carrier core, resulting in the smoothness of the magnetic carrier surface and the unevenness of the coating material in the coating process, thereby deteriorating the charging and stress resistance during durability.

  In the present invention, the carrier core used for the magnetic carrier is a magnetic fine particle dispersed resin core containing magnetic fine particles and a binder resin.

  This is because when the magnetic fine particle-dispersed resin core of the present invention is used, the carrier core component contains a binder resin, so that the adhesion with the selectively oriented coating material is increased and the process speed is increased. Even when applied, it is durable and stable.

The specific surface area BET3 (m ² / g) according to the BET method of the magnetic fine particles used in the magnetic fine particle dispersed resin core used in the present invention is preferably 2.0 to 20.0 (m ² / g).

When the magnetic fine particle dispersed resin core is produced when the specific surface area BET3 (m ² / g) by the BET method of the magnetic fine particle is in the above range, the dispersibility of the magnetic fine particles in the magnetic fine particle dispersed resin core is good. For this reason, the uniformity of charging on the surface of the magnetic carrier is good. Further, the surface of the produced magnetic fine particle-dispersed resin core is also uniform, and it is preferable to coat the coating material easily and uniformly.

When the specific surface area BET3 is less than 2.0 (m ² / g), it may be difficult to encapsulate the core in the production of the magnetic fine particle dispersed resin core.

Further, when the specific surface area BET3 exceeds 20.0 (m ² / g), when the magnetic fine particle-dispersed resin core is produced, the dispersibility of the magnetic fine particles themselves deteriorates and the inclusion in a uniformly dispersed state is reduced. Have difficulty. For this reason, the specific resistance in the magnetic fine particle-dispersed resin core becomes non-uniform, and the charge imparting property to the toner may become unstable.

  Further, the magnetic fine particle dispersed core contains 70 to 95 parts by mass of magnetic fine particles with respect to 100 parts by mass of the magnetic fine particle dispersed core, thereby reducing the true specific gravity of the magnetic carrier and sufficiently securing the mechanical strength. Preferred above, more preferred is 80 to 92 parts by weight.

  Furthermore, in order to change the magnetic properties of the magnetic carrier, it is preferable that the magnetic fine particle-dispersed resin core contains magnetic fine particles and further non-magnetic inorganic compound fine particles. The inclusion of magnetic fine particles and further nonmagnetic inorganic compound fine particles is preferable because the nonmagnetic inorganic compound fine particles have a larger specific resistance than the magnetic fine particles, so that the specific resistance of the magnetic fine particle dispersed resin core can be controlled.

  The magnetic fine particles are contained in an amount of 50 to 100% by mass based on the total amount of the magnetic fine particles and the non-magnetic inorganic compound fine particles, thereby adjusting the strength of magnetization of the magnetic carrier to prevent the magnetic carrier from adhering. It is preferable in adjusting the specific resistance value of the carrier.

The magnetic fine particles used in the magnetic fine particle-dispersed resin core of the present invention are preferably magnetite fine particles, or magnetic ferrite fine particles containing at least an iron element and a magnesium element, and nonmagnetic inorganic used in the magnetic fine particle-dispersed resin core. The compound fine particles are preferably hematite (α-Fe ₂ O ₃ ) fine particles from the viewpoint of adjusting the magnetic properties and true specific gravity of the magnetic carrier.

The specific surface area BET4 (m ² / g) of the nonmagnetic inorganic compound fine particles is 1.0 to 10.0 (m ² / g), and the specific surface area BET3 and the specific surface area BET4 satisfy BET3> BET4. It is preferable.

The nonmagnetic inorganic compound has a specific surface area BET4 (m ² / g) according to the BET method of 1.0 to 10.0 (m ² / g), and the specific surface area BET3 and the specific surface area BET4 satisfy BET3> BET4. In the case of manufacturing the magnetic fine particle dispersed resin core, it is preferable because the specific resistance of the magnetic fine particle dispersed resin core can be controlled without inhibiting the dispersibility of the magnetic fine particles in the magnetic fine particle dispersed resin core.

When the specific surface area BET4 is less than 1.0 (m ² / g), it is not preferable since it is difficult to encapsulate the core in the core when the magnetic fine particle-dispersed resin core is produced, and the imparted chargeability may deteriorate.

Further, when the specific surface area BET4 exceeds 10.0 (m ² / g), the dispersibility of the nonmagnetic inorganic compound fine particles themselves deteriorates when the magnetic fine particle dispersed resin core is produced, and the dispersibility of the magnetic fine particles also deteriorates. There are things to do. For this reason, the dispersibility of the fine particles as a whole of the magnetic fine particle dispersed resin core is deteriorated, and the specific resistance in the magnetic fine particle dispersed resin core becomes non-uniform.

  Further, when the specific surface area BET3 and the specific surface area BET4 are BET3 ≦ BET4, when the magnetic fine particle dispersed resin core is produced, the nonmagnetic inorganic compound fine particles are selectively included, and the magnetic fine particle dispersed resin core The uniformity of the may be impaired. As a result, the charge imparting property may be deteriorated.

  Specific examples of the coating resin contained in the coating material used for the magnetic carrier of the present invention include perfluoropolymers such as polyvinyl fluoride, polyvinylidene fluoride, polytrifluoroethylene, and polyfluorochloroethylene, and polytetrafluoroethylene. , Polyperfluoropropylene, copolymer of vinylidene fluoride and acrylic monomer, copolymer of vinylidene fluoride and trifluorochloroethylene, copolymer of tetrafluoroethylene and hexafluoropropylene, vinyl fluoride And a resin such as a copolymer of vinylidene fluoride and a copolymer of vinylidene fluoride and tetrafluoroethylene. Particularly, the coating resin preferably used in the present invention is represented by the following formula (1).

〔式中、ｍは１乃至２０のいずれかの整数を示す。〕
で示されるパーフルオロアルキルユニットを有するメタクリル酸エステルユニットまたはアクリル酸エステルユニットで構成される重合体又は共重合体である。

[Wherein, m represents an integer of 1 to 20. ]
It is a polymer or copolymer comprised by the methacrylic acid ester unit or acrylate ester unit which has the perfluoroalkyl unit shown by these.

  The above-mentioned coat resins can be used alone or in combination. Further, an additive such as a curing agent may be mixed with the thermoplastic resin and cured for use.

  In the present invention, when m exceeds 20, the coating resin is likely to be precipitated from the solvent, and it may be difficult to obtain a good coating film when coating. It is more preferable that m is 5 to 15 in order to have good toner releasability and coat film forming property, and it is more preferable that m is 5 to 9.

  Moreover, it is excellent in adhesiveness with a carrier core, preferably using the coating resin which has following formula (2).

〔式中、ｍは上記式（１）と同義であり、ｎは１乃至１０のいずれかの整数を示す。〕
さらに、コート樹脂は、下記式（３）

[In formula, m is synonymous with the said Formula (1), and n shows the integer in any one of 1 thru | or 10. ]
Furthermore, the coating resin is represented by the following formula (3)

〔式中、Ｚは水素原子またはアルキル基を示し、ｍ及びｎは上記式（２）と同義である。〕
で示されるユニットで構成される重合体又は共重合体であることが好ましい。

[In formula, Z shows a hydrogen atom or an alkyl group, and m and n are synonymous with the said Formula (2). ]
It is preferable that it is a polymer or copolymer comprised by the unit shown by these.

  Moreover, it is preferable that Z in the said Formula (3) is a methyl group.

  Furthermore, the coat resin is preferably a copolymer having a unit represented by the following formula (4) and a unit represented by the following formula (5) in order to improve the toner releasability from the carrier.

〔式中、ｍ及びｎは上記式（２）と同義であり、ｌは１以上の整数を示す。〕

[In formula, m and n are synonymous with the said Formula (2), and l shows an integer greater than or equal to 1. ]

[Wherein, R ₁ represents a hydrogen atom or a methyl group, R ₂ represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms, and k represents an integer of 1 or more. ]
Further, even when a coating resin obtained by graft copolymerization with the copolymer unit of the above formulas (4) and (5) with the unit represented by the above formula (4) can maintain the toner releasability characteristics, The coating material is also excellent in resistance to peeling from the carrier core, and is particularly preferable.

  When a thermoplastic resin is used as the coating resin contained in the coating material, this thermoplastic resin has a weight average molecular weight of 10,000 in a gel permeation chromatograph (GPC) which is a soluble component of tetrahydrofuran (THF). It is preferably from 300,000 in terms of enhancing the strength of the coating material and the peel resistance between the coating material and the surface of the magnetic fine particle dispersed resin core.

  The coated resin preferably has a main peak in the molecular weight region of 2,000 to 100,000 in the GPC chromatogram of the THF soluble component, and further has a sub peak or a peak in the molecular weight region of 2,000 to 100,000. More preferably, it has a shoulder. Most preferably, the coating resin has a main peak in the molecular weight range of 20,000 to 100,000 and a sub-peak or shoulder in the molecular weight range of 2,000 to 19,000 in the GPC chromatogram of the THF soluble component. It is to have. Since the coating resin satisfies the above molecular weight distribution, it is possible to develop a large number of sheets even with a toner having a small particle diameter, charging stability to the toner, and adhesion of external additives to the surface of the magnetic carrier. The prevention is further improved.

  Further, when the coating resin is a graft copolymer, the weight average molecular weight of the trunk of the graft copolymer is 15,000 to 200,000, and the weight average molecular weight of the branches is 3,000 to 10,000. Preferably there is. The weight average molecular weight of the coating resin can be adjusted by the polymerization conditions of the trunk portion of the graft copolymer and the polymerization conditions of the branch portion of the graft polymer.

  In the present invention, when a coating material containing a coating resin having the above graft copolymer is used, when coating a magnetic fine particle dispersed resin core, the coating material is excellent in resistance to peeling from the surface of the magnetic fine particle dispersed resin core. This is preferable.

  The amount of the coating material is preferably 0.3 to 4.0 parts by mass with respect to 100 parts by mass of the magnetic material-dispersed resin core. More preferred is 0.4 to 3.5 parts by mass, and still more preferred is 0.5 to 3.2 parts by mass.

  When the amount of the coating material is within the above range, good toner releasability can be obtained, and image defects such as white spots are unlikely to occur. If the amount is less than 0.3 parts by mass, the surface of the carrier core cannot be sufficiently coated, and the effects of the present invention may be difficult to obtain. If the amount exceeds 4.0 parts by mass, a uniform coating can be achieved during coating. In some cases, the charge up or the carrier core surface is exposed, and toner spent in that portion may occur. In addition, the specific resistance of the magnetic carrier increases, and image defects such as white spots may occur.

  The contact angle of the magnetic carrier of the present invention is preferably 95 to 125 °, more preferably 100 to 120 °. When the contact angle of the magnetic carrier is less than 95 °, the toner agent cannot be sufficiently separated from the magnetic carrier, and white spots may occur. When the angle exceeds 125 °, white spots are improved and developability is improved. On the other hand, when the developing sleeve is rotated at a high speed, toner scattering occurs and the inside of the machine may be contaminated.

  The coating material preferably contains 1 to 40 parts by mass of fine particles with respect to 100 parts by mass of the coating resin.

  When the coating material contains fine particles within the above range, charging stability and toner separation can be improved, and image defects such as white spots can be prevented. When the amount is less than 1 part by mass, the effect of addition of fine particles may not be obtained. When the amount exceeds 40 parts by mass, fine particles may be missing from the coat layer during durability, and durability may be inferior.

  As for the particle size of the fine particles contained in the coating material, the maximum peak value in the particle size distribution on a number basis is preferably 0.08 to 0.70 μm, more preferably 0.10 to 0.50 μm. By containing fine particles having a particle size in this range in the coating material, toner separation can be improved. When the maximum peak value in the particle size distribution on the number basis is less than 0.08 μm, it may be difficult to disperse the fine particles in the coating material. When the thickness exceeds 70 μm, missing from the coat layer may occur during durability, resulting in poor durability.

  As the fine particles contained in the coating material, either organic or inorganic fine particles can be used, but the fine particles contained in the coating material maintain the shape of the particles when coating the magnetic fine particle dispersed resin core. is required. Therefore, the fine particles contained in the coating material are preferably resin fine particles or inorganic fine particles, and more preferably cross-linked resin fine particles are used. Specifically, resin particles such as crosslinked polymethyl methacrylate resin particles, crosslinked polystyrene resin particles, melamine resin particles, phenol resin particles, or nylon resin particles, inorganic particles such as silica particles, titanium oxide particles, or alumina particles are used. be able to. Among these, the resin fine particles are resin fine particles selected from cross-linked polymethyl methacrylate resin fine particles, cross-linked polystyrene resin fine particles, and melamine resin fine particles, and the resin fine particles are contained in one or more kinds of coating materials. Is preferable from the viewpoint of charging stability.

  From the viewpoint of charge control, conductive fine particles may be contained as fine particles contained in the coating material.

  Specifically, the conductive fine particles are conductive fine particles selected from carbon black fine particles, magnetite fine particles, graphite fine particles, titanium oxide fine particles, alumina fine particles, zinc oxide fine particles, and tin oxide fine particles, and the conductive fine particles are It is preferable to contain 1 type, or 2 or more types in a coating material. In particular, as the fine particles having conductivity, carbon black fine particles are preferable because they have a small particle size and can be used without obstructing irregularities caused by fine particles on the surface of the magnetic carrier. The particle size of the carbon black fine particles preferably has a maximum peak value of 10 to 60 nm in the particle size distribution on the basis of the number, and more preferably 15 to 50 nm. It is preferable to use fine particles having a particle size in the above range in order to remove residual charges on the surface of the magnetic carrier satisfactorily and to prevent detachment of fine particles from the magnetic carrier.

  The DBP oil absorption of carbon black is preferably 20 to 500 ml / 100 g, more preferably 25 to 300 ml / 100 g, and particularly preferably 30 to 200 ml / 100 g.

  When the DBP oil absorption is within the above range, the residual charge on the surface of the magnetic carrier is efficiently removed, which is preferable for controlling the charging of the magnetic carrier. If it is less than 20 ml / 100 g, the structure of carbon black is short, so that efficient charge removal is not performed and the effect of addition may be difficult to develop.

  These conductive fine particles are used in an amount of 1 to 25 parts by mass with respect to 100 parts by mass of the coating resin for reducing the specific resistance of the magnetic carrier and for removing residual charges on the surface of the magnetic carrier. preferable. When the amount is less than 1 part by mass, the effect of removing the residual charge on the surface of the magnetic carrier may be difficult to be exhibited. When the amount exceeds 15 parts by mass, dispersion in the coating material becomes unstable and excessive Due to the charge removal effect, the charge imparting ability of the carrier itself may decrease.

  The magnetic carrier of the present invention preferably has an average particle size of 10 to 80 μm in the particle size distribution on a number basis. Particles having an average particle size of less than 10 μm in the particle size distribution on the basis of number are likely to adhere to the carrier, and those having an average particle size of more than 80 μm may not be able to be charged satisfactorily because the specific surface area of the toner is small. There is. In particular, in order to improve image quality and prevent carrier adhesion, the thickness is more preferably 15 to 60 μm, still more preferably 20 to 45 μm.

  The average particle size in the particle size distribution on the basis of the number of magnetic carriers is randomly extracted by scanning electron microscope (100 to 5000 times) with 300 or more magnetic carrier particles having a particle size of 0.1 μm or more in the horizontal direction by a digitizer. The ferret diameter is measured as the particle size of the magnetic carrier, and the average particle size is calculated in the particle size distribution based on the number of magnetic carriers.

The magnetic carrier of the present invention has a magnetization strength (σ1000) of 15 to 80 Am ² / kg (emu / g) measured under a magnetic field of 1000 × (10 ³ / 4π) · A / m (1000 oersted). More preferably, it is 20 to 70 Am ² / kg. When the strength of magnetization (σ1000) exceeds 80 Am ² / kg, the stress on the toner in the developer magnetic brush increases, the toner deteriorates, and the spent on the carrier is likely to occur. . Further, when the magnetization intensity (σ1000) is less than 15 Am ² / kg, the magnetic binding force to the sleeve is lost, and the carrier adheres and adheres to the surface of the photoreceptor, which may cause a defect in the image.

The true specific gravity of the magnetic carrier of the present invention is preferably 2.5 to 4.0 g / cm ³ , more preferably 3.0 to 3.8 g / cm ³ . When the true specific gravity of the magnetic carrier is within this range, the load on the toner is small in the stirring and mixing of the magnetic carrier and the toner, the toner spent on the magnetic carrier is suppressed, and the carrier adhesion to the photoreceptor is suppressed. Therefore, it is preferable.

  As a method for producing a magnetic fine particle dispersed resin core, there is a method in which a monomer of a binder resin and magnetic fine particles are mixed and the monomer is polymerized to obtain magnetic fine particle dispersed resin core particles. At this time, as monomers used for polymerization, vinyl monomers, bisphenols and epichlorohydrin for forming epoxy resins; phenols and aldehydes for forming phenol resins; urea and aldehydes for forming urea resins Melamine and aldehydes are used. For example, as a method of producing magnetic fine particle dispersed core particles using a curable phenolic resin, magnetic fine particles are placed in an aqueous medium, and phenols and aldehydes are polymerized in the presence of a basic catalyst in the aqueous medium. There is a method of obtaining fine particle dispersed core particles.

  As another method for producing the magnetic fine particle dispersed resin core, a vinyl-type or non-vinyl type thermoplastic resin, magnetic fine particles, and other additives are sufficiently mixed by a mixer, and then heated rolls, kneaders, and extruders. There is a method of obtaining magnetic fine particle dispersed resin core particles by melting and kneading using such a kneader, cooling this, and then pulverizing and classifying. At this time, it is preferable that the obtained magnetic fine particle-dispersed resin core particles are spheroidized thermally or mechanically and used as the magnetic fine particle-dispersed resin core particles for the magnetic carrier. As the binder resin, a thermosetting resin such as a phenol resin, a melamine resin, or an epoxy resin is preferable in terms of excellent durability, impact resistance, and heat resistance. As the binder resin, it is more preferable to use a phenol resin in order to more suitably express the characteristics of the present invention.

  As phenols for producing a phenol resin, in addition to phenol, alkylphenols such as m-cresol, p-tert-butylphenol, o-propylphenol, resorcinol, bisphenol A, and part or all of benzene nucleus or alkyl group Are compounds having a phenolic hydroxyl group such as halogenated phenols substituted with a chlorine atom or a bromine atom. Of these, phenol (hydroxybenzene) is more preferable.

  Examples of aldehydes include formaldehyde and furfural in the form of either formalin or paraaldehyde. Of these, formaldehyde is particularly preferable.

  The molar ratio of aldehydes to phenols is preferably 1 to 4, particularly preferably 1.2 to 3. When the molar ratio of aldehydes to phenols is less than 1, particles are difficult to generate, and even if they are generated, the resin does not easily cure, so the strength of the generated particles tends to be weak. On the other hand, when the molar ratio of aldehydes to phenols is larger than 4, unreacted aldehydes remaining in the aqueous medium after the reaction tend to increase.

  Examples of the basic catalyst used in the condensation polymerization of phenols and aldehydes include those used in the production of ordinary resol type resins. Examples of such a basic catalyst include aqueous ammonia, hexamethylenetetramine and alkylamines such as dimethylamine, diethyltriamine, and polyethyleneimine. The molar ratio of these basic catalysts to phenols is preferably 0.02 to 0.3.

  In the two-component developer containing the toner of the present invention and a magnetic carrier, the toner has at least toner particles containing a binder resin, a release agent, and a colorant, and the magnetic carrier is at least magnetic. In a magnetic carrier obtained by coating the surface of a magnetic fine particle-dispersed resin core containing fine particles and a binder resin with a coating material having a coating resin, the carbon element abundance ratio (Fatom) of the surface of the magnetic carrier ( The ratio (Fatom / Catom) to Cattom) is 0.10 to 0.85, and the ratio of the fluorine element abundance (Fatom) on the surface of the magnetic carrier to the carbon element abundance (Catom) (Fatom / Catom) , The carbon element abundance ratio of the fluorine element abundance ratio (Fcalc) that can be theoretically calculated from the molecular structure of the coating resin Ratio calc) (Fcalc / Ccalc) ratio of (Fatom / Catom) / (Fcalc / Ccalc) is characterized by a 1.01 to 3.00.

  By using such a two-component developer, the contamination of the toner to the magnetic carrier is reduced, and good durability stability is achieved. This is because, when the magnetic carrier contained in the two-component developer is within the above range, the fluorine element abundance ratio on the surface of the magnetic carrier can be increased, so that the surface energy of the surface of the magnetic carrier is reduced, so that the toner It was possible to control the releasability from the surface of the magnetic carrier, and as a result, the toner releasability during development was improved, and image defects such as white spots could be improved.

  The toner of the present invention is characterized in that the transmittance of light having a wavelength of 600 nm with respect to a dispersion obtained by dispersing the toner in an aqueous solution of 45% by volume of methanol is 10 to 70%. When the transmittance of light having a wavelength of 600 nm with respect to a dispersion obtained by dispersing the toner in a 45% by volume aqueous solution of methanol is within the above range, it is possible to improve the toner separation from the magnetic carrier and prevent white spots even in durability. it can. The transmittance is more preferably 10 to 60%, still more preferably 15 to 50%.

  Because the wettability of the binder resin and the release agent contained in the toner is different, when the toner is dispersed in a water-methanol solution, the toner may be different depending on the state of the release agent in the vicinity of the toner surface. The concentration of the dispersed water-methanol solution becomes different. In the present invention, by utilizing this property and measuring the transmittance, it is used as an index of the state of presence of the release agent in the vicinity of the toner surface. Further, in the present invention, when a methanol aqueous solution having a methanol content of around 45% by volume is used, the sensitivity to the difference in wettability between the binder resin and the release agent is good. Volume% + water 55 volume%).

  In other words, this measurement method is to forcibly disperse the toner once in a methanol-water mixed solvent so that the characteristics of the amount of release agent such as wax on the surface of each toner particle can be easily obtained, and after a certain period of time. By measuring the transmittance of the toner, the amount of the release agent such as wax on the toner surface can be accurately grasped.

  For example, when a large amount of hydrophobic wax is present on the toner surface, the dispersed toner is difficult to wet with the solvent and does not settle, so the transmittance becomes a high value such as 70%. If it is present in a small amount, the resin in which many polyester units are present exhibits hydrophilicity due to its strong polarity, and when dispersed uniformly, the transmittance becomes a low value such as 10%.

  When the transmittance is less than 10%, the amount of the release agent present in the vicinity of the toner surface is small, the developability after durability is good, and the white spots are very good. Gloss may be reduced. When the transmittance exceeds 70%, the low-temperature fixability is improved, but the release agent is released from the toner, migrates to the surface of the developing sleeve and the magnetic carrier, becomes contaminated, and developability decreases with durability. White spots may also worsen.

  The transmittance is determined by controlling the temperature and time of pulverization and shape adjustment at the time of toner production, the conditions of the type of release agent used and the type of dispersant for the release agent, and controlling the conditions of the release agent on the toner surface. It can be adjusted by controlling the presence state. The transmittance can be measured using a spectrophotometer.

  In the endothermic curve in the differential thermal analysis (DSC) measurement, the toner of the present invention preferably has a peak temperature of the maximum endothermic peak in the range of 30 to 200 ° C. in the range of 60 to 130 ° C. More preferably, it is in the range of 65 to 125 ° C, and particularly preferably in the range of 65 to 110 ° C.

  The release agent such as wax is preferably contained in an amount of 0.1 to 20 parts by mass, more preferably 0.5 to 10 parts by mass with respect to 100 parts by mass of the binder resin.

  Further, the toner used in the present invention has a molecular weight distribution measured by gel permeation chromatography (GPC) of a resin component having a main peak in a molecular weight range of 3,500 to 15,000, preferably a molecular weight. It has an area of 4,000 to 13,000. Further, the weight average molecular weight (Mw) / number average molecular weight (Mn) of the resin component of the toner is preferably 3.0 or more, and more preferably 5.0 or more. When the main peak is in a region having a molecular weight of less than 3,500, the high temperature offset resistance of the toner may be reduced. On the other hand, when the main peak is in a region having a molecular weight of more than 15000, sufficient low-temperature fixability of toner and OHP permeability may be deteriorated. Moreover, when Mw / Mn is less than 3.0, good offset resistance may decrease.

  The binder resin used in the toner of the present invention is preferably a resin having at least a polyester unit.

  The “polyester unit” used in the present invention means a part derived from polyester. Specifically, as a component constituting the polyester unit, a divalent or higher valent alcohol monomer component and a divalent or higher carboxylic acid, It means an acid monomer component such as a divalent or higher carboxylic acid anhydride and a divalent or higher carboxylic acid ester.

  In the toner of the present invention, it is preferable to use a resin having a component subjected to condensation polymerization using a component constituting these polyester units as a part of the raw material.

  The binder resin used in the present invention is a polyester resin, a hybrid resin having a polyester unit and a vinyl polymer unit, a mixture of a hybrid resin and a vinyl polymer, or a mixture of a hybrid resin and a polyester resin. Or a resin selected from a polyester resin, a hybrid resin, and a vinyl polymer, or a mixture of a polyester resin and a vinyl polymer.

  The hybrid resin is formed by a transesterification reaction between a polyester unit component and a vinyl polymer unit obtained by polymerizing a monomer component having a carboxylic acid ester group such as a methacrylic acid ester unit or an acrylic acid ester unit. A graft copolymer (or block copolymer) in which a vinyl polymer is a trunk polymer and a polyester unit is a branch polymer is formed.

  As a dihydric or higher alcohol monomer component which is a polyester unit component, specifically, as a dihydric alcohol monomer component, polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, poly Oxypropylene (3.3) -2,2-bis (4-hydroxyphenyl) propane, polyoxyethylene (2.0) -2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene (2.0 ) -Polyoxyethylene (2.0) -2,2-bis (4-hydroxyphenyl) propane, alkylene oxide of bisphenol A such as polyoxypropylene (6) -2,2-bis (4-hydroxyphenyl) propane Adduct, ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propyl Pyrene glycol, 1,3-propylene glycol, 1,4-butanediol, neopentyl glycol, 1,4-butenediol, 1,5-pentanediol, 1,6-hexanediol, 1,4-cyclohexanedimethanol, Examples include dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, bisphenol A, and hydrogenated bisphenol A.

  Examples of the trivalent or higher alcohol monomer component include sorbit, 1,2,3,6-hexanetetrol, 1,4-sorbitan, pentaerythritol, dipentaerythritol, tripentaerythritol, 1,2,4-butanetriol. 1,2,5-pentanetriol, glycerin, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane, 1,3,5-trihydroxymethylbenzene, etc. Is mentioned.

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

  Examples of the trivalent or higher carboxylic acid monomer component include trimellitic acid, pyromellitic acid, polyvalent carboxylic acid such as benzophenone tetracarboxylic acid and its anhydride, and the like.

  Examples of other monomers include polyhydric alcohols such as oxyalkylene ethers of novolak type phenol resins.

  Among them, in particular, a bisphenol derivative represented by the following formula (6) is a dihydric alcohol monomer component, and a carboxylic acid component comprising a divalent or higher carboxylic acid or an acid anhydride thereof, or a lower alkyl ester thereof (for example, Because fumaric acid, maleic acid, maleic anhydride, phthalic acid, terephthalic acid, trimellitic acid, pyromellitic acid, etc.) are acid monomer components, resins that are polycondensed with these polyester unit components have good charging characteristics. preferable.

（式中、Ｒ_３及びＲ_４はそれぞれ独立してエチレン基又はプロピレン基を示し、ｘ及びｙはそれぞれ独立して１以上の整数であり、かつｘ＋ｙの平均値は２〜１０である。）

(In the formula, R ₃ and R ₄ each independently represent an ethylene group or a propylene group, x and y are each independently an integer of 1 or more, and the average value of x + y is 2 to 10).

  The binder resin contained in the toner of the present invention is preferably a resin having at least a polyester unit, and more preferably, the polyester unit component contained in the total binder resin is based on the total binder resin. It is preferable for the effect of the present invention to be 30% by mass or more. More preferably, it is 40 mass% or more, Most preferably, it is 50 mass% or more.

  When the polyester unit component contained in the total binder resin used in the toner particles is 30% by mass or more based on the total binder resin, it is preferable in terms of fixing property and charge stability.

  The following are mentioned as a vinyl-type monomer for producing | generating the vinyl-type polymer unit or vinyl-type polymer used for hybrid resin. Styrene; o-methylstyrene, m-methylstyrene, p-methylstyrene, α-methylstyrene, p-phenylstyrene, p-ethylstyrene, 2,4-dimethylstyrene, pn-butylstyrene, p-tert- Butyl styrene, pn-hexyl styrene, pn-octyl styrene, pn-nonyl styrene, pn-decyl styrene, pn-dodecyl styrene, p-methoxy styrene, p-chloro styrene, 3, Styrene and derivatives thereof such as 4-dichlorostyrene, m-nitrostyrene, o-nitrostyrene, p-nitrostyrene; styrene unsaturated monoolefins such as ethylene, propylene, butylene and isobutylene; unsaturated such as butadiene and isoprene Polyenes; vinyl chloride, vinyl chloride, vinyl bromide, fluoride Vinyl halides such as vinyl; vinyl esters such as vinyl acetate, vinyl propionate, vinyl benzoate; methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-methacrylate Α-methylene aliphatic monocarboxylic acid esters such as octyl, dodecyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, phenyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate; methyl acrylate, ethyl acrylate Propyl acrylate, n-butyl acrylate, isobutyl acrylate, n-octyl acrylate, dodecyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, 2-acrylate Acrylic esters such as lorethyl and phenyl acrylate; 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 pyrrole; N-vinyl compounds such as N-vinyl carbazole, N-vinyl indole and N-vinyl pyrrolidone; vinyl naphthalenes; acrylic acid or methacrylic acid derivatives such as acrylonitrile, methacrylonitrile and acrylamide.

  In addition, unsaturated dibasic acids such as maleic acid, citraconic acid, itaconic acid, alkenyl succinic acid, fumaric acid, mesaconic acid; maleic anhydride, citraconic anhydride, itaconic anhydride, alkenyl succinic anhydride, etc. Unsaturated dibasic acid anhydride; maleic acid methyl half ester, maleic acid ethyl half ester, maleic acid butyl 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 half ester, fumaric acid methyl half ester, mesaconic acid methyl half ester unsaturated dibasic acid half ester; dimethylmaleic acid, dimethyl fumaric acid unsaturated dibasic acid ester; acrylic acid, meta Α, β-unsaturated acids such as rillic acid, crotonic acid and cinnamic acid; α, β-unsaturated acid anhydrides such as crotonic acid anhydride and cinnamic acid anhydride, the α, β-unsaturated acid and lower fatty acids And monomers having a carboxyl group such as alkenylmalonic acid, alkenylglutaric acid, alkenyladipic acid, acid anhydrides and monoesters thereof.

  Further, acrylic acid or methacrylic acid esters such as 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate; 4- (1-hydroxy-1-methylbutyl) styrene, 4- (1-hydroxy-1) -Methylhexyl) Monomers having a hydroxy group such as styrene.

  The vinyl polymer or vinyl polymer unit used in the hybrid resin may have a crosslinked structure crosslinked with a crosslinking agent having two or more vinyl groups, but the crosslinking agent used in this case is Examples of aromatic divinyl compounds include divinylbenzene and divinylnaphthalene; examples of diacrylate compounds linked by an alkyl chain include ethylene glycol diacrylate, 1,3-butylene glycol diacrylate, and 1,4-butanediol di Examples include acrylate, 1,5-pentanediol diacrylate, 1,6 hexanediol diacrylate, neopentyl glycol diacrylate, and the above compounds in which acrylate is replaced by methacrylate; linked by an alkyl chain containing an ether bond. Diacrylate compound Examples include diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol # 400 diacrylate, polyethylene glycol # 600 diacrylate, dipropylene glycol diacrylate, and acrylates of the above compounds as methacrylates. Examples of diacrylate compounds linked by a chain containing an aromatic group and an ether bond include, for example, polyoxyethylene (2) -2,2-bis (4-hydroxyphenyl) propane diacrylate, poly Examples include oxyethylene (4) -2,2-bis (4-hydroxyphenyl) propane diacrylate and those obtained by replacing acrylates of the above compounds with methacrylate.

  Polyfunctional cross-linking agents include pentaerythritol triacrylate, trimethylol ethane triacrylate, trimethylol propane triacrylate, tetramethylol methane tetraacrylate, oligoester acrylate, and acrylates of the above compounds replaced with methacrylate; triallylcia Examples include nurate and triallyl trimellitate.

  The hybrid resin used in the present invention preferably contains a monomer component capable of reacting with both resin components in the vinyl polymer or unit and / or the polyester resin or unit. Among the monomers constituting the polyester resin or unit, those capable of reacting with the vinyl polymer or unit include, for example, unsaturated dicarboxylic acids such as phthalic acid, maleic acid, citraconic acid and itaconic acid, or anhydrides thereof. It is done. Among the monomers constituting the vinyl polymer or unit, those capable of reacting with the polyester resin or unit include those having a carboxyl group or a hydroxy group, and acrylic acid or methacrylic acid esters.

  As a method for obtaining a reaction product of a vinyl polymer and a polyester resin, either a polymer or a resin containing a monomer component capable of reacting with each of the vinyl polymer and the polyester resin listed above is present. A method obtained by polymerizing one or both of the polymers or resins is preferred.

  Examples of the polymerization initiator used in producing the vinyl polymer or vinyl polymer unit of the present invention include 2,2′-azobisisobutyronitrile, 2,2′-azobis (4- Methoxy-2,4-dimethylvaleronitrile), 2,2′-azobis (-2,4-dimethylvaleronitrile), 2,2′-azobis (-2methylbutyronitrile), dimethyl-2,2′- Azobisisobutyrate, 1,1′-azobis (1-cyclohexanecarbonitrile), 2- (carbamoylazo) -isobutyronitrile, 2,2′-azobis (2,4,4-trimethylpentane), 2- Phenylazo-2,4-dimethyl-4-methoxyvaleronitrile, 2,2′-azobis (2-methyl-propane), methyl ethyl ketone peroxide, acetyla Ketone peroxides such as ton peroxide, cyclohexanone peroxide, 2,2-bis (t-butylperoxy) butane, t-butyl hydroperoxide, cumene hydroperoxide, 1,1,3,3-tetramethyl Butyl hydroperoxide, di-t-butyl peroxide, t-butylcumyl peroxide, di-cumyl peroxide, α, α'-bis (t-butylperoxyisopropyl) benzene, isobutyl peroxide, octanoyl peroxide Decanoyl peroxide, lauroyl peroxide, 3,5,5-trimethylhexanoyl peroxide, benzoyl peroxide, m-trioyl peroxide, di-isopropyl peroxydicarbonate, di-2-ethylhexyl Ruperoxy dicarbonate, di-n-propyl peroxydicarbonate, di-2-ethoxyethyl peroxycarbonate, di-methoxyisopropyl peroxydicarbonate, di (3-methyl-3-methoxybutyl) peroxycarbonate, acetyl Cyclohexylsulfonyl peroxide, t-butyl peroxyacetate, t-butyl peroxyisobutyrate, t-butyl peroxyneodecanoate, t-butyl peroxy 2-ethylhexanoate, t-butyl peroxylaurate T-butyl peroxybenzoate, t-butyl peroxyisopropyl carbonate, di-t-butyl peroxyisophthalate, t-butyl peroxyallyl carbonate, t-amyl peroxy 2-ethylhexanoate, -t- butyl peroxy hexahydro terephthalate, di -t- butyl peroxy azelate and the like.

  As a manufacturing method which can prepare the hybrid resin used by this invention, the manufacturing method shown to the following (1)-(6) can be mentioned, for example.

  (1) A method in which a vinyl polymer and a polyester resin are blended after production. The blend is produced by dissolving and swelling in an organic solvent (for example, xylene) and then distilling off the organic solvent. The hybrid resin component is synthesized by separately producing a vinyl polymer and a polyester resin, dissolving and swelling in a small amount of an organic solvent, adding an esterification catalyst and an alcohol, and performing a transesterification reaction by heating. Thus, a hybrid resin having a polyester unit and a vinyl polymer unit can be obtained.

  (2) A method of producing a hybrid resin component having a polyester unit and a vinyl polymer unit by producing and reacting a polyester resin in the presence of the vinyl polymer after production. The hybrid resin component is produced by a reaction between a vinyl polymer (a vinyl monomer can be added if necessary) and a polyester monomer (alcohol, carboxylic acid) and / or polyester resin. Also in this case, an organic solvent can be appropriately used.

  (3) A method for producing a hybrid resin component having a polyester unit and a vinyl polymer unit by producing and reacting a vinyl polymer in the presence of the polyester resin after production. The hybrid resin component is produced by a reaction between a polyester resin (a polyester monomer can be added if necessary) and a vinyl monomer and / or a vinyl polymer.

  (4) After the vinyl polymer and the polyester resin are produced, the hybrid resin component is produced by adding a vinyl monomer and / or a polyester monomer (alcohol, carboxylic acid) in the presence of these polymer units. Also in this case, an organic solvent can be appropriately used.

  (5) After producing a hybrid resin component having a polyester unit and a vinyl polymer unit, by adding a vinyl monomer and / or a polyester monomer (alcohol, carboxylic acid) and performing an addition polymerization and / or a condensation polymerization reaction. A vinyl polymer and / or polyester resin, or further a hybrid resin component is produced. In this case, as the hybrid resin component having the polyester unit and the vinyl polymer unit, those produced by the production methods (2) to (4) can be used, and if necessary, by a known production method. What was manufactured can also be used. Furthermore, an organic solvent can be used as appropriate.

  (6) By mixing a vinyl monomer and a polyester monomer (alcohol, carboxylic acid, etc.) and continuously performing addition polymerization and condensation polymerization reaction, a vinyl polymer, a polyester resin, a polyester unit and a vinyl polymer unit are obtained. A hybrid resin component is produced. Furthermore, an organic solvent can be used as appropriate.

  In the production methods (1) to (6) above, the vinyl copolymer unit and / or the polyester unit can use a plurality of polymer units having different molecular weights and cross-linking degrees.

  In the present invention, the vinyl polymer or vinyl polymer unit means a vinyl homopolymer, a vinyl copolymer, a vinyl monopolymer unit, or a vinyl copolymer unit.

  Further, the molecular weight distribution measured by gel permeation chromatography (GPC) of the resin having the polyester unit of the present invention has a main peak in the region of molecular weight 3,500 to 15,000, preferably molecular weight. It has in the area | region of 4,000 thru | or 13,000, and it is preferable that Mw / Mn is 3.0 or more, and it is more preferable that it is 5.0 or more. When the main peak is in a region having a molecular weight of less than 3,500, the high temperature offset resistance of the toner decreases. On the other hand, when the main peak is in a region having a molecular weight of more than 15000, sufficient low-temperature fixability of the toner and OHP permeability are deteriorated. Moreover, when Mw / Mn is less than 3.0, good offset resistance is reduced.

  The glass transition temperature (Tg) of the resin having the polyester unit of the present invention is preferably 40 to 90 ° C., and the softening temperature (Tm) is 80 to 150 ° C., storage stability, low temperature fixability, high temperature offset resistance, It is preferable for achieving both dispersibility of the colorant.

  The acid value of the resin is preferably less than 50 mgKOH / g from the viewpoint of improving the development durability stability and the dispersibility of the colorant.

  Examples of the release agent used in the present invention include aliphatic hydrocarbon waxes such as low molecular weight polyethylene, low molecular weight polypropylene, alkylene copolymers, microcrystalline wax, paraffin wax, and Fischer-Tropsch wax, and fats such as oxidized polyethylene wax. Oxides of aromatic hydrocarbon waxes or block copolymers thereof; waxes based on fatty acid esters such as carnauba wax, behenyl behenate wax, montanate wax, and fatty acids such as deoxidized carnauba wax Examples include esters obtained by partially or fully deoxidizing esters. In addition, saturated linear fatty acids such as palmitic acid, stearic acid, and montanic acid; unsaturated fatty acids such as brandic acid, eleostearic acid, and valinalic acid; stearyl alcohol, aralkyl alcohol, behenyl alcohol, carnauvyl alcohol, and seryl alcohol Saturated alcohols such as melyl alcohol; polyhydric alcohols such as sorbitol; fatty acids such as palmitic acid, stearic acid, behenic acid, montanic acid, and stearyl alcohol, aralkyl alcohol, behenyl alcohol, carnauvir alcohol, seryl alcohol, Esters of alcohols such as merisyl alcohol; fatty acid amides such as linoleic acid amide, oleic acid amide, lauric acid amide; methylene bis stearic acid amide, ethylene biscaprin Saturated fatty acid bisamides such as amides, ethylene bislauric acid amides, hexamethylene bisstearic acid amides; Unsaturated fatty acid amides such as sebacic acid amides; aromatic bisamides such as m-xylene bis-stearic acid amide, N, N ′ distearyl isophthalic acid amide; calcium stearate, calcium laurate, zinc stearate, magnesium stearate Aliphatic metal salts such as those 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 and many others Price Calls partial ester; and methyl ester compounds having hydroxyl groups obtained by and hydrogenated vegetable oils and the like.

  Examples of the release agent particularly preferably used in the present invention include aliphatic hydrocarbon waxes and esterified products that are esters of fatty acids and alcohols. For example, low molecular weight alkylene polymer obtained by radical polymerization of alkylene under high pressure with Ziegler catalyst or metallocene catalyst under low pressure; alkylene polymer obtained by thermally decomposing high molecular weight alkylene polymer; synthesis containing carbon monoxide and hydrogen A synthetic hydrocarbon wax obtained from the distillation residue of hydrocarbons obtained from the gas by the age method or by hydrogenating them is preferred. Furthermore, the thing which fractionated hydrocarbon wax by the use of the press perspiration method, the solvent method, vacuum distillation, or a fractional crystallization system is used more preferably. The hydrocarbon as a base is synthesized by the reaction of carbon monoxide and hydrogen using a metal oxide catalyst (mostly two or more multi-component systems) [for example, the Jintol method, the Hydrocol method (the fluidized catalyst bed Hydrocarbon compounds synthesized by use); hydrocarbons with up to several hundred carbon atoms obtained by the age method (using the identified catalyst bed) from which a large amount of wax-like hydrocarbons can be obtained; alkylene such as ethylene by Ziegler catalyst Polymerized hydrocarbons are preferred because they are linear hydrocarbons with little branching, small and long saturation. In particular, a wax synthesized by a method that does not rely on polymerization of alkylene is also preferred from its molecular weight distribution. Paraffin wax is also preferably used.

  Further, the release agent used in the present invention preferably has a peak temperature of a maximum endothermic peak in a range of 60 to 130 ° C. in an endothermic curve in differential thermal analysis (DSC) measurement. . More preferably, it is in the range of 65 to 125 ° C, and particularly preferably in the range of 65 to 110 ° C.

  When the maximum endothermic peak temperature of the release agent is in the range of 60 to 130 ° C., moderate fine dispersibility in the toner particles can be achieved, which is preferable in order to exhibit the effects of the present invention. On the other hand, when the maximum endothermic peak is less than 60 ° C., the blocking resistance of the toner deteriorates. Conversely, when the maximum endothermic peak exceeds 130 ° C., the fixability tends to deteriorate.

  As the colorant used in the toner of the present invention, known dyes and / or pigments are used. Although the pigment alone may be used, it is more preferable from the viewpoint of the image quality of the full-color image that the combination of the dye and the pigment improves the sharpness.

  Examples of the coloring pigment for magenta toner include condensed azo compounds, diketopyrrolopyrrole compounds, anthraquinones, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazolone compounds, thioindigo compounds, and perlin compounds. Specifically, C.I. I. Pigment Red 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 21, 22, 23, 30, 31, 32, 37, 38, 39, 40, 41, 48: 2, 48: 3, 48: 4, 49, 50, 51, 52, 53, 54, 55, 57: 1, 58, 60, 63, 64, 68, 81: 1, 83, 87, 88, 89, 90, 112, 114, 122, 123, 144, 146, 150, 163, 166, 169, 177, 184, 185, 202, 206, 207, 209, 220, 221, 254, C.I. I. Pigment violet 19, C.I. I. Bat red 1, 2, 10, 13, 15, 23, 29, 35, etc. are mentioned.

  Examples of the magenta toner dye include C.I. I solvent red 1, 3, 8, 23, 24, 25, 27, 30, 49, 81, 82, 83, 84, 100, 109, 121, C.I. I. Disper thread 9, C.I. I. Solvent Violet 8, 13, 14, 21, 27, C.I. I. Oil-soluble dyes such as Disper Violet 1, C.I. I. Basic Red 1, 2, 9, 12, 13, 14, 15, 17, 18, 22, 23, 24, 27, 29, 32, 34, 35, 36, 37, 38, 39, 40, C.I. I. Basic dyes such as basic violet 1, 3, 7, 10, 14, 15, 21, 25, 26, 27, and 28 may be mentioned.

  Examples of the color pigment for cyan toner include C.I. I. Pigment Blue 1, 2, 3, 7, 15: 2, 15: 3, 15: 4, 16, 17, 60, 62, 66; I. Bat Blue 6, C.I. I. Acid Blue 45 or a copper phthalocyanine pigment in which 1 to 5 phthalimidomethyl groups are substituted on a phthalocyanine skeleton having a structure represented by the following formula.

〔式中、ｎは１乃至５のいずれかの整数を示す。〕

[Wherein n represents an integer of 1 to 5. ]

  Examples of the colored pigment for yellow include condensed azo compounds, isoindolinone compounds, anthraquinone compounds, azo metal compounds, methine compounds, and allylamide compounds. Specifically, C.I. I. Pigment Yellow 1, 2, 3, 4, 5, 6, 7, 10, 11, 12, 13, 14, 15, 16, 17, 23, 62, 65, 73, 74, 83, 93, 95, 97, 109, 110, 111, 120, 127, 128, 129, 147, 155, 168, 174, 180, 181, 185, 191, C.I. I. Bat yellow 1, 3, 20 and the like. In addition, C.I. I. Direct Green 6, C.I. I. Basic Green 4, C.I. I. Dyes such as Basic Green 6 and Solvent Yellow 162 can also be used.

  As the black colorant used in the present invention, carbon black, iron oxide, and those which are toned in black using the yellow / magenta / cyan colorant shown above can be used.

  In the toner of the present invention, it is preferable to use a toner obtained by mixing a colorant in advance with the binder resin of the present invention to form a master batch. Then, the colorant can be favorably dispersed in the toner by melt-kneading the colorant master batch and other raw materials (binder resin, wax, etc.).

  When the colorant is made into a master batch using the resin of the present invention, the dispersibility of the colorant is not deteriorated even when a large amount of the colorant is used. Excellent color reproducibility such as transparency. Further, a toner having a large covering power on the transfer material can be obtained. Further, by improving the dispersibility of the colorant, it is possible to obtain an image with excellent durability stability of toner chargeability and maintaining high image quality.

  The amount of the colorant used in the toner is preferably 0.1 to 15 parts by mass, more preferably 0.5 to 12 parts by mass, and most preferably 2 to 10 parts by mass with respect to 100 parts by mass of the binder resin. . This is preferable in terms of color reproducibility and developability.

  A known charge control agent can be used for the toner of the present invention in order to stabilize the chargeability. The charge control agent varies depending on the type of charge control agent and the physical properties of other toner particle constituent materials, but generally 0.1 to 10 parts by mass per 100 parts by mass of the binder resin is preferably contained in the toner particles. More preferably, 0.1 to 5 parts by mass are contained. As such a charge control agent, there are known one that controls the toner to be negatively charged and one that controls the toner to be positively charged. One or two kinds of various kinds of charge control agents are used depending on the kind and use of the toner. The above can be used.

  Negatively chargeable charge control agents include salicylic acid metal compounds, naphthoic acid metal compounds, dicarboxylic acid metal compounds, polymer compounds having sulfonic acid or carboxylic acid in the side chain, boron compounds, urea compounds, silicon compounds, calixarene Etc. are available. As the positively chargeable charge control agent, a quaternary ammonium salt, a polymer compound having the quaternary ammonium salt in the side chain, a guanidine compound, an imidazole compound, or the like can be used. The charge control agent may be added internally or externally to the toner particles.

  In particular, the color toner of the present invention is preferably an aromatic metal carboxylic acid compound that is colorless, has a high toner charging speed, and can stably maintain a constant charge amount.

  The toner of the present invention can be used by improving the fluidity of the toner by pulverizing and classifying and mixing a fluidizing agent and the like with a mixer such as a Henschel mixer.

  Any fluidizing agent can be used as long as it can be added to the colorant-containing resin particles to increase the fluidity before and after the addition. For example, fluororesin powders such as vinylidene fluoride fine powder, polytetrafluoroethylene fine powder, titanium oxide fine powder, alumina fine powder, wet process silica, fine process silica such as dry process silica, silane compound, and organic Examples include treated silica that has been surface-treated with a silicon compound, a titanium coupling agent, silicone oil, and the like.

For example, the dry process silica is a fine powder produced by vapor phase oxidation of a silicon halogen compound, which is called dry process silica or fumed silica, and is manufactured by a conventionally known technique. For example, a thermal decomposition oxidation reaction of silicon tetrachloride gas in an oxyhydrogen flame is used, and the basic reaction formula is as follows.
SiCl ₄ + 2H ₂ + O ₂ → SiO ₂ + 4HCl
In this production process, it is also possible to obtain a composite fine powder of silica and other metal oxides by using other metal halogen compounds such as aluminum chloride or titanium chloride together with silicon halogen compounds. . The particle size is preferably within the range of 0.001 to 2 μm as the average primary particle size, and particularly preferably, silica fine powder within the range of 0.002 to 0.2 μm is used.

  In the case of titanium oxide fine powder, fine particles of titanium oxide obtained by low-temperature oxidation (thermal decomposition, hydrolysis) of sulfuric acid method, chlorine method, volatile titanium compounds such as titanium alkoxide, titanium halide, titanium acetylacetonate are used. As the crystal system, any of anatase type, rutile type, mixed crystal type thereof, and amorphous type can be used.

  And if it is alumina fine powder, buyer method, improved buyer method, ethylene chlorohydrin method, underwater spark discharge method, organoaluminum hydrolysis method, aluminum alum pyrolysis method, ammonium aluminum carbonate pyrolysis method, aluminum chloride flame Alumina fine powder obtained by a decomposition method is used. As the crystal system, α, β, γ, δ, ξ, η, θ, κ, χ, ρ type, mixed crystal type, amorphous type, α, δ, γ, θ, mixed crystal can be used. A mold or an amorphous material is preferably used.

  The hydrophobizing method is applied by chemical or physical treatment with an organosilicon compound that reacts or physically adsorbs with the inorganic fine powder.

  As a preferred method, silica fine powder produced by vapor phase oxidation of a silicon halogen compound is treated with an organosilicon compound. Examples of such organosilicon compounds are hexamethyldisilazane, trimethylsilane, trimethylchlorosilane, trimethylethoxysilane, dimethyldichlorosilane, methyltrichlorosilane, allyldimethylchlorosilane, allylphenyldichlorosilane, benzyldimethylchlorosilane. , Bromomethyldimethylchlorosilane, α-chloroethyltrichlorosilane, β-chloroethyltrichlorosilane, chloromethyldimethylchlorosilane, triorganosilylmercaptan, trimethylsilylmercaptan, triorganosilylacrylate, vinyldimethylacetoxysilane, dimethylethoxysilane, dimethyl Dimethoxysilane, diphenyldiethoxysilane, hexamethyldisiloxane, 1,3-divinyltetramethyldisiloxane 1,3-diphenyltetramethyldisiloxane, and dimethylpolysiloxane containing 2 to 12 siloxane units per molecule and containing hydroxyl groups bonded to one Si at each terminal unit. These are used alone or in a mixture of two or more.

As the fluidizing agent used in the present invention, the above-mentioned dry process silica treated with a coupling agent having an amino group or silicone oil may be used as necessary to achieve the object of the present invention. Absent. The fluidizing agent used in the present invention has good results when the specific surface area by nitrogen adsorption measured by the BET method is 30 m ² / g or more, preferably 50 m ² / g or more. The fluidizing agent is used in an amount of 0.01 to 8 parts by weight, preferably 0.1 to 4 parts by weight, based on 100 parts by weight of the toner.

  When a two-component developer is prepared by mixing the toner of the present invention and a magnetic carrier, the mixing ratio is usually 2 to 15% by mass, preferably 4 to 13% by mass, as the toner concentration in the developer. Good results are obtained. If the toner concentration is less than 2% by mass, the image density tends to decrease, and if it exceeds 15% by mass, fogging or in-machine scattering tends to occur.

  Next, a procedure for manufacturing toner will be described. The toner of the present invention melts and kneads a binder resin, a colorant, a wax, and an arbitrary material, cools and pulverizes the material, and spheroidizes and classifies the pulverized product as necessary. If necessary, it can be produced by mixing the fluidizing agent.

  First, in the raw material mixing step, as a toner internal additive, at least a resin and a colorant are weighed and mixed in a predetermined amount and mixed. Examples of the mixing apparatus include a double-con mixer, a V-type mixer, a drum-type mixer, a super mixer, a Henschel mixer, and a Nauter mixer.

  Further, the toner raw materials blended and mixed as described above are melt-kneaded to melt the resins and disperse the colorant and the like therein. In the melt-kneading step, for example, a batch kneader such as a pressure kneader or a Banbury mixer, or a continuous kneader can be used. In recent years, single-screw or twin-screw extruders have become mainstream due to the advantage of being capable of continuous production, for example, KTK type twin screw extruder manufactured by Kobe Steel, TEM type twin screw extruder manufactured by Toshiba Machine Co., Ltd. A twin screw extruder manufactured by Kay Sea Kay, a co-kneader manufactured by Buss, etc. are generally used. Furthermore, the colored resin composition obtained by melt-kneading the toner raw material is rolled by a two-roll roll after melt-kneading, and then cooled through a cooling step of cooling by water cooling or the like.

  In general, the cooled colored resin composition obtained above is then pulverized to a desired particle size in a pulverization step. In the pulverization step, first, coarse pulverization is performed with a crusher, a hammer mill, a feather mill or the like, and further, pulverization is performed with a kryptron system manufactured by Kawasaki Heavy Industries, Ltd., a super rotor manufactured by Nisshin Engineering Co., Ltd. or the like. After that, if necessary, classification is performed using a classifier such as an inertia class elbow jet (manufactured by Nippon Steel Mining Co., Ltd.) or a centrifugal classifier turboplex (manufactured by Hosokawa Micron Co., Ltd.), and the weight average particle diameter A classified product of 3 to 11 μm is obtained.

  If necessary, surface modification and spheronization may be performed using, for example, a hybridization system manufactured by Nara Machinery Co., Ltd. or a mechano-fusion system manufactured by Hosokawa Micron. In such a case, if necessary, a sieving machine such as a wind-type sieve high voltor (manufactured by Shin Tokyo Machine Co., Ltd.) may be used. Furthermore, as a method of externally adding the external additive, a predetermined amount of classified toner and various known external additives are blended, and a high-speed stirrer that gives a shearing force to the powder such as a Henschel mixer or a super mixer is removed. A method of stirring and mixing can be used as an accessory.

  A method for measuring physical properties of the magnetic carrier and toner of the present invention is as follows.

<Measurement of specific surface area BET of magnetic carrier, carrier core, magnetic fine particles, non-magnetic inorganic compound fine particles>
First, if necessary, pretreatment is performed to prepare a sample. For example, in the case of a carrier core such as a magnetic fine particle-dispersed resin core, the coating material component is completely dissolved and separated by dissolving the magnetic carrier in a solvent such as acetone and toluene and allowing to stand for 24 hours. Dry to obtain a carrier core. In addition, the magnetic fine particles and / or non-magnetic inorganic compound used for the carrier core is obtained by completely incinerating the resinous portion of the carrier core with an electric furnace or the like to obtain an incineration ash component, and then using a magnet, It is possible to separate non-magnetic inorganic compounds and obtain each.

  These samples are subjected to a specific surface area measuring apparatus Tristar 3000 (manufactured by Shimadzu Corporation) according to the BET method, and nitrogen gas is adsorbed on the sample surface, and the specific surface area is calculated using the BET multipoint method. Prior to the measurement of the specific surface area, about 9 g of a sample is precisely weighed in a sample tube and evacuated at room temperature for 24 hours.

<Measurement of fluorine element abundance ratio and carbon element abundance ratio on magnetic carrier surface>
The fluorine element abundance (Fatom) and the carbon element abundance (Catom) on the surface of the magnetic carrier are measured by X-ray electron spectroscopy (XPS) under the following measurement conditions.
Device: PHI Quantum 2000
X-ray source: Al Kα
Acceleration voltage: 20 kV
Catom and Fatom can be calculated from the obtained peak profile. From the calculated value, the ratio (Fatom / Catom) of the fluorine element abundance ratio (Fatom) to the carbon element abundance ratio (Catom) on the surface of the magnetic carrier can be calculated.

<Analysis of composition of coating material>
As a method for separating the coating material from the magnetic carrier, a solvent soluble in the coating material (for example, acetone, toluene, etc.) is used, ultrasonic separation is performed with an ultrasonic disperser, and then the core is separated with a magnet. Do. Thereafter, using a centrifugal separator, the fine particles added to the coating material are separated, and the supernatant (resin solution component) is separated and evaporated to dryness to obtain the coating material resin component. About 50 mg of this sample is put into a sample tube of φ5 mm, and CDCl ₃ is added as a solvent and dissolved to obtain a measurement sample. The measurement conditions are shown below.
Measuring apparatus: FT NMR apparatus JNM-EX400 (manufactured by JEOL Ltd.)
Measurement frequency: 400MHz
Pulse condition: 6.9 μs
Data points: 32768
Frequency range: 10500Hz
Integration count: 16 times Measurement temperature: 25 ° C
From the molecular structure of the coating resin obtained by the above measurement, Fcalc / Ccalc can be calculated. For example, when the molar ratio between methyl methacrylate and Compound Example 1 is 5: 1 in the resin component comprising methyl methacrylate and Compound Example 1 represented by the following formula (7),

Methyl methacrylate C5, H8, O2 Compound Example 1 C14, H9, O2, F17 Fcalc / Ccalc = 17 / (6 × 5 + 14) = 0.386
Fcal / Ccal of the coating resin component is 0.386.

<Measurement of resistivity of magnetic carrier, magnetic fine particles, non-magnetic inorganic compound fine particles>
The specific resistance values of the magnetic carrier, magnetic fine particles, and nonmagnetic inorganic compound fine particles are measured using the measuring apparatus shown in FIG. Pre-treatment and sample preparation are performed as necessary. Magnetic fine particles and nonmagnetic inorganic compound fine particles used for the magnetic carrier can be obtained in the same manner as the pretreatment for the measurement of the specific surface area BET.

The specific resistance is measured by filling the cell E with carrier particles, placing the lower electrode 11 and the upper electrode 12 in contact with the filled carrier particles 17, applying a voltage between these electrodes, and flowing at that time. A method for determining the specific resistance by measuring the current is used. The measurement conditions for the specific resistance in the present invention are as follows: the contact area S between the filled carrier particles and the electrode is about 2.4 cm ² , the sample thickness d is about 0.2 cm, and the load of the upper electrode 12 is 240 g. The voltage is applied in the order of application conditions I, II, and III, and the current at the applied voltage in application condition III is measured. Thereafter, the thickness d of the sample is accurately measured, the specific resistance (Ω · cm) at each electric field strength (V / cm) is obtained by calculation, and the specific resistance at the electric field strength of 3000 V / cm is determined by the ratio of the magnetic carrier of the sample. It was resistance.
Application condition I: (Changed from 0V to 1000V: Increased in steps of 200V every 30 seconds)
II: (Hold for 30 seconds at 1000V)
III: (Change from 1000V to 0V: Decrease in steps of 200V every 30 seconds)
Specific resistance of magnetic carrier (Ω · cm) = (applied voltage (V) / measured current (A)) × S (cm ² ) / d (cm)
Electric field strength (V / cm) = applied voltage (V) / d (cm)
<Molecular weight distribution of binder resin, toner, and coating material by GPC measurement>
The molecular weight of the chromatogram by gel permeation chromatography (GPC) is measured under the following conditions.

The column was stabilized in a heat chamber at 40 ° C., and tetrahydrofuran (THF) as a solvent was passed through the column at this temperature at a flow rate of 1 ml / min, and the sample concentration was adjusted to 0.05 to 0.6% by mass. About 50 to 200 μl of THF sample solution is injected and measured. In measuring the molecular weight of a sample, the molecular weight distribution of the sample is calculated from the relationship between the logarithmic value of a calibration curve prepared from several types of monodisperse polystyrene standard samples and the number of counts (retention time). Examples of standard polystyrene samples for preparing a calibration curve include those manufactured by Tosoh Corporation or Pressure Chemical Co. The molecular weights manufactured are 6 × 10 ² , 2.1 × 10 ³ , 4 × 10 ³ , 1.75 × 10 ⁴ , 5.1 × 10 ⁴ , 1.1 × 10 ⁵ , 3.9 × 10 ⁵ , 8 It is suitable to use a standard polystyrene sample of at least about 10 points, using .6 × 10 ⁵ , 2 × 10 ⁶ , 4.48 × 10 ⁶ . An RI (refractive index) detector is used as the detector.

As a column, in order to accurately measure a molecular weight region of 10 ^{3 to} 2 × 10 ⁶ , it is preferable to combine a plurality of commercially available polystyrene gel columns. For example, shodex GPC KF-801, 802, 803 manufactured by Showa Denko KK , 804, 805, 806, and 807, and the combination of μ-styragel 500, 10 ³ , 10 ⁴ , and 10 ⁵ manufactured by Waters.

<Measurement of contact angle of magnetic carrier>
As a method for measuring the contact angle of the magnetic carrier, a contact angle with water is measured using a WTMY-232A wet tester manufactured by Sankyo Piotech.

  13.2 g of the magnetic carrier is gently put into the measuring cell, and a tapping operation is performed for 1 minute at a tapping speed of 30 times / min using a Tapping Machine PTM-1 manufactured by Sankyo Piotech Co., Ltd. This is set in a measuring apparatus and measured.

  First, the specific surface area of the powder layer is obtained by the air permeation method, and then the pressure inflection point is obtained by the constant flow method. The contact angle of the powder particles is calculated from both.

<Measurement of particle size of fine particles in coating material>
The particle size of the fine particles in the coating material was determined by scanning the component obtained by dissolving the coating material from a magnetic carrier in a solvent in which the coating material is soluble, such as toluene, using a scanning electron microscope (50,000 times). Randomly extract 500 or more, measure the major axis and minor axis with a digitizer, average the particle size, and at the peak of the particle size distribution of 500 or more particles (from the column histogram divided every 10 nm) The number average particle size is calculated with the following particle size.

<Measurement of magnetization intensity of magnetic carrier>
The strength of magnetization of the magnetic carrier is determined from the magnetic properties of the magnetic carrier and the true specific gravity of the magnetic carrier. The magnetic characteristics of the magnetic carrier can be measured by using an oscillating magnetic field type magnetic characteristic automatic recording apparatus BHV-30 manufactured by Riken Denshi Co., Ltd. As a measuring method, a cylindrical plastic container is filled with a magnetic carrier so as to be sufficiently dense, while an external magnetic field of 79.6 kA / m (1 kilo-Oersted) is formed, and in this state, the magnetic material filled in the container is filled. Measure the magnetization moment of the carrier. Further, the actual mass of the magnetic carrier filled in the container is measured to determine the magnetization strength (Am ² / kg) of the magnetic carrier.

<Measurement of true specific gravity of magnetic carrier>
The true specific gravity of the magnetic carrier can be determined by a dry automatic densimeter autopycnometer.

<Measurement of Light Transmittance for Dispersion Dispersed in 45% by Volume of Methanol in Toner>
(I) Preparation of toner dispersion An aqueous solution having a volume mixing ratio of methanol: water of 45:55 is prepared. 10 ml of this aqueous solution is placed in a 30 ml sample bottle (Nippon Denka Glass: SV-30), and 20 mg of toner is impregnated on the liquid surface to cover the bottle. Then, it is made to shake at 2.5S-1 for 5 seconds with a Yayoi type shaker (model: YS-LD). At this time, the angle of shaking is such that the shaking column moves 15 degrees forward and 20 degrees backward, assuming that the vertical (vertical) of the shaker is 0 degree. The sample bottle is fixed to a fixing holder (with the sample bottle lid fixed on the extension at the center of the column) attached to the tip of the column. After removing the sample bottle, the dispersion after 30 seconds is used as a dispersion for measurement.

(Ii) Transmittance measurement The dispersion obtained in (i) is placed in a 1 cm square quartz cell, and the transmittance at a wavelength of 600 nm of the dispersion after 10 minutes using a spectrophotometer MPS2000 (manufactured by Shimadzu Corporation) ( %).
Transmittance (%) = I / I ₀ × 100 I ₀ : Incident beam, I: Transmitted beam <Measurement of maximum endothermic peak in DSC of toner and wax>
The maximum endothermic peak of the toner and the wax can be measured according to ASTM D3418-82 using a differential thermal analyzer (DSC measuring device) and DSC2920 (TA Instruments Japan).
Temperature curve: Temperature increase I (30 ° C. to 200 ° C., temperature increase rate 10 ° C./min)
Temperature drop I (200 ° C-30 ° C, temperature drop rate 10 ° C / min)
Temperature increase II (30 ° C to 200 ° C, temperature increase rate 10 ° C / min)
As a measuring method, 5 to 20 mg, preferably 10 mg of a measurement sample is accurately weighed. This is put into an aluminum pan, and an empty aluminum pan is used as a reference, and measurement is performed at a temperature rise rate of 10 ° C./min and normal temperature and humidity in a measurement temperature range of 30 to 200 ° C. The maximum endothermic peak of the toner is determined in the process of temperature increase II, the one having the highest height from the baseline in the region above the endothermic peak of the resin Tg, or the endothermic peak of the resin Tg overlaps with another endothermic peak. If this is difficult, the maximum endothermic peak of the toner of the present invention is defined as the highest peak from the maximum peak of the overlapping peaks.

<Measurement of acid value of resin>
Basic operation conforms to JIS K-0070.
(1) The sample pulverized product 0.5 to 2.0 (g) is precisely weighed, and the mass of the sample is set to W (g).
(2) A sample is put into a 300 (ml) beaker, and a mixed solution 150 (ml) of toluene / ethanol (4/1) is added and dissolved.
(3) Titrate with a potentiometric titrator using an ethanol solution of 0.1 mol / l KOH. (For example, automatic titration using a potentiometric titrator AT-400 (win workstation) manufactured by Kyoto Electronics Co., Ltd. and an ABP-410 electric burette can be used.)
(4) The amount of KOH solution used at this time is set to S (ml), the blank is measured at the same time, and the amount of KOH solution used at this time is set to B (ml).
(5) The acid value is calculated by the following formula. f is a factor of KOH.
Acid value (mgKOH / g) = {(SB) × f × 5.61} / W
<Measurement of glass transition temperature of resin>
The glass transition temperature (Tg) of the resin is measured according to ASTM D3418-82 using a differential scanning calorimeter (DSC measuring device), DCS-7 (manufactured by PerkinElmer), DSC2920 (manufactured by TA Instruments Japan), and the like. To do.

  The sample to be measured is precisely weighed 5 to 20 mg, preferably 10 mg. The sample is put in an aluminum pan, and an empty aluminum pan is used as a reference, and measurement is performed at a temperature rise rate of 10 ° C./min at room temperature and humidity in a measurement range of 30 to 200 ° C. In this temperature raising process, a specific heat change is obtained in the temperature range of 40 ° C to 100 ° C. At this time, the intersection of the intermediate point line of the baseline before and after the change in specific heat and the differential heat curve is defined as the glass transition temperature Tg of the resin of the present invention.

<Method for measuring softening point of resin>
According to JIS K 7210, it refers to what is measured by Koka flow tester. A specific measurement method is shown below. While a 1 cm ³ sample was heated at a heating rate of 6 ° C./min using a Koka type flow tester (manufactured by Shimadzu Corporation), a load of 1960 N / m ² (20 kg / cm ² ) was applied by a plunger, and the diameter was 1 mm. , A nozzle with a length of 1 mm is pushed out, thereby drawing a plunger descending amount (flow value) -temperature curve, where the height of the S-shaped curve is h, the temperature corresponding to h / 2 (resin Is the softening point (Tm) of the resin.

<Measurement of toner particle size distribution>
As a measuring device, Coulter Counter TA-II or Coulter Multisizer II (manufactured by Coulter Inc.) is used. As the electrolytic solution, an about 1% NaCl aqueous solution is used. As the electrolytic solution, an electrolytic solution prepared using primary sodium chloride or, for example, ISOTON (registered trademark) -II (manufactured by Coulter Scientific Japan) can be used.

  As a measurement method, 0.1 to 5 ml of a surfactant (preferably alkylbenzenesulfone hydrochloride) is added as a dispersant to 100 to 150 ml of the electrolytic aqueous solution, and 2 to 20 mg of a measurement sample is further added. The electrolytic solution in which the sample is suspended is dispersed for about 1 to 3 minutes with an ultrasonic disperser, and the volume and number of the sample are measured for each channel by the measuring device using a 100 μm aperture as the aperture. The volume distribution and the number distribution are calculated. From these obtained distributions, the weight average particle diameter of the sample is determined. As channels, 2.00 to 2.52 μm; 2.52 to 3.17 μm; 3.17 to 4.00 μm; 4.00 to 5.04 μm; 5.04 to 6.35 μm; 6.35 to 8. 00 μm; 8.00 to 10.08 μm; 10.08 to 12.70 μm; 12.70 to 16.00 μm; 16.00 to 20.20 μm; 20.20 to 25.40 μm; 25.40 to 32.00 μm; 13 channels of 32-40.30 μm are used.

  Specific examples of the present invention will be described below, but the present invention is not limited to these examples.

(Example of manufacturing carrier core A)
Magnetite fine particles (specific surface area BET3 is 7.0 (m ² / g), specific resistance is 5 × 10 ⁷ (Ω · cm)), hematite fine particles (specific surface area BET4 is 3.8 (m ² / g), ratio Resistance of 2 × 10 ⁸ (Ω · cm)) is 4.0% by mass and 2.0% by mass of silane coupling agent (3- (2-aminoethylaminopropyl) trimethoxysilane), respectively. In addition, high-speed mixing and stirring was performed at 100 ° C. or higher in the container to make each fine particle lipophilic.
-Phenol 10 parts by mass-Formaldehyde solution (formaldehyde 37 mass% aqueous solution) 6 parts by mass-Treated magnetite fine particles 76 parts by mass-Treated hematite fine particles 8 parts by mass The above materials, 28 mass% ammonia water 5 parts by mass, water 10 parts by mass was placed in a flask, heated and maintained at 85 ° C. over 30 minutes while stirring and mixing, and cured by polymerization reaction for 3 hours. Then, after cooling to 30 degreeC and adding water, the supernatant liquid was removed, the precipitate was washed with water, and then air-dried. Next, this was dried under reduced pressure (5 hPa or less) at a temperature of 60 ° C. to obtain a magnetic fine particle dispersed resin core (carrier core A) in which magnetic fine particles were dispersed. The physical properties of the obtained carrier core A were an average particle size of 35 μm and a specific surface area BET2 of 0.07 (m ² / g) in the particle size distribution on a number basis.

(Example of manufacturing carrier core B)
Magnetite fine particles (specific surface area BET3 is 10.0 (m ² / g), specific resistance is 2 × 10 ⁷ (Ω · cm)), hematite fine particles (specific surface area BET4 is 2.0 (m ² / g), specific ratio Resistance is 5 × 10 ⁸ (Ω · cm)), and 5.0% by mass and 1.0% by mass of a silane coupling agent (3- (2-aminoethylaminopropyl) trimethoxysilane), respectively. In addition, high-speed mixing and stirring was performed at 100 ° C. or higher in the container to make each fine particle lipophilic.
-Phenol 10 parts by mass-Formaldehyde solution (formaldehyde 37% by weight aqueous solution) 6 parts by mass-Treated magnetite fine particles 76 parts by mass-Treated hematite fine particles 8 parts by mass The above materials, 28 parts by mass of ammonia water 7 parts by mass, water 8 parts by mass was placed in a flask, heated and maintained at 85 ° C. over 30 minutes with stirring and mixing, and cured by polymerization for 3 hours. Then, after cooling to 30 degreeC and adding water, the supernatant liquid was removed, the precipitate was washed with water, and then air-dried. Subsequently, this was dried under reduced pressure (5 mmHg or less) at a temperature of 60 ° C. to obtain a magnetic fine particle dispersed resin core (carrier core B) in which magnetic fine particles were dispersed. The physical properties of the obtained carrier core B were an average particle size of 50 μm and a specific surface area BET2 of 0.08 (m ² / g) in the particle size distribution on a number basis.

(Example of production of carrier core C)
Magnetite fine particles (specific surface area BET3 is 10.0 (m ² / g), specific resistance is 2 × 10 ⁸ (Ω · cm), 5.0 mass% titanium coupling agent isopropyltri (N-amino) Ethyl-aminoethyl) titanate was added, and the mixture was mixed and stirred at 100 ° C. or higher in a container to make the fine particles lipophilic.
-Phenol 10 parts by mass-Formaldehyde solution (formaldehyde 37% by mass aqueous solution) 6 parts by mass-The above treated magnetite fine particles 84 parts by mass The above materials, 6% by mass 28% ammonia water, and 12 parts by mass water are placed in a flask and stirred. The mixture was heated and maintained at 85 ° C. for 30 minutes with mixing, and was cured by polymerization for 3 hours. Then, after cooling to 30 degreeC and adding water, the supernatant liquid was removed, the precipitate was washed with water, and then air-dried. Subsequently, this was dried under reduced pressure (5 mmHg or less) at a temperature of 60 ° C. to obtain a magnetic fine particle dispersed resin core (carrier core C) in which magnetic fine particles were dispersed. The physical properties of the obtained carrier core C were an average particle size of 25 μm and a specific surface area BET2 of 0.10 (m ² / g) in the particle size distribution on a number basis.

(Example of manufacturing carrier core D)
The mixture was weighed so that the molar ratio was Fe ₂ O ₃ = 52 mol%, CuO = 16 mol%, and MgO = 32 mol%, and mixed for 10 hours using a ball mill. This was calcined at 900 ° C. for 2 hours, pulverized with a ball mill, and further granulated with a spray dryer. This was sintered at 1150 ° C. for 10 hours, pulverized and further classified to obtain a magnetic carrier core (carrier core D). The physical properties of the obtained carrier core D were an average particle size of 35 μm and a specific surface area BET2 of 0.15 (m ₂ / g) in the particle size distribution on a number basis.

(Production Example 1 of Coat Resin)
Following formula (8)

3 parts by weight of a methyl methacrylate macromer having an ethylenically unsaturated group at one end and having a weight average molecular weight of 5,000, the following formula (7)

146 parts by mass of a compound having a structure represented by the formula: 51 parts by mass of methyl methacrylate were added to a four-necked flask equipped with a reflux condenser, a thermometer, a nitrogen suction tube and a mixing type stirring apparatus, and further 100 parts by mass of toluene. , 100 parts by mass of methyl ethyl ketone and 2.4 parts by mass of azobisisovaleronitrile were added and kept at 80 ° C. for 10 hours under a nitrogen stream.

[Wherein, a1, b1, c1 and d1 each independently represents an integer of 1 or more. ]
The graft copolymer (A) solution (solid content 35 mass%) which has a unit shown by this was obtained. The weight average molecular weight by the gel permeation chromatogram (GPC) of the graft copolymer (A) was 20,000. The graft copolymer (A) was Fcalc / Ccalc = 0.38.

(Manufacture example 2 of coat resin)
The same procedure as in Production Example 1 was conducted except that 164 parts by mass of the compound having the structure represented by the above formula (7), 33 parts by mass of methyl methacrylate, and 3 parts by mass of azobisisovaleronitrile were used. A graft copolymer (B) having the units indicated was obtained. The weight average molecular weight by the gel permeation chromatogram (GPC) of the graft copolymer (B) was 23,000. The graft copolymer (B) was Fcalc / Ccalc = 0.48.

(Coating resin production example 3)
In Production Example 1, a graft copolymer having the unit represented by the above formula (9) was prepared in the same manner except that the compound example was changed to 17 parts by mass and 90 parts by mass of methyl methacrylate having the structure represented by the above formula (7). (C) was obtained. The weight average molecular weight by the gel permeation chromatogram (GPC) of the graft copolymer (C) was 25,000. The graft copolymer (C) was Fcalc / Ccalc = 0.08.

(Manufacture example 4 of coat resin)
A graft copolymer having the unit represented by the above formula (9) was prepared in the same manner as in Production Example 1 except that 15 parts by mass of the compound having the structure represented by the above formula (7) and 92 parts by mass of methyl methacrylate were changed. (D) was obtained. The weight average molecular weight by the gel permeation chromatogram (GPC) of the graft copolymer (D) was 28,000. The graft copolymer (D) was Fcalc / Ccalc = 0.05.

(Production Example 5 of Coat Resin)
The same procedure as in Production Example 1 was conducted except that the compound was changed to 169 parts by mass of the compound having the structure represented by the formula (7), 28 parts by mass of methyl methacrylate, and 3 parts by mass of azobisisovaleronitrile. A graft copolymer (E) having a unit represented by 9) was obtained. The weight average molecular weight by the gel permeation chromatogram (GPC) of the graft copolymer (E) was 24,000. The graft copolymer (E) had Fcalc / Ccalc = 0.50.

(Manufacture example 6 of coat resin)
3 parts by mass of a methyl methacrylate macromer having a weight average molecular weight of 9,000 having an ethylenically unsaturated group at one end represented by the above formula (8), the following formula (10)

249 parts by mass of a compound having a structure represented by the formula: 48 parts by mass of methyl methacrylate were added to a four-necked flask equipped with a reflux condenser, a thermometer, a nitrogen suction tube and a mixing type stirring apparatus, and further 200 parts by mass of methyl ethyl ketone. , 0.5 parts by mass of azobisisovaleronitrile was added, and the mixture was kept at 80 ° C. for 10 hours under a nitrogen stream.

[Wherein, a2, b2, c2 and d2 each independently represents an integer of 1 or more. ]
The graft copolymer (F) solution (solid content 35 mass%) which has a unit shown by this was obtained. The weight average molecular weight by the gel permeation chromatogram (GPC) of the graft copolymer (F) was 180,000. The graft copolymer (F) was Fcalc / Ccalc = 0.44.

(Coating resin production example 7)
Following formula (12)

3100 parts by mass of the compound having the structure represented by the following formula is added to a four-necked flask equipped with a reflux condenser, a thermometer, a nitrogen suction pipe and a mixing type stirring apparatus, and further 200 parts by mass of methyl ethyl ketone and azobisisovaleronitrile. 1.5 parts by mass was added and kept at 80 ° C. for 10 hours under a nitrogen stream.

The polymer (G) solution (solid content 35 mass%) which has a unit shown by was obtained. The weight average molecular weight by the gel permeation chromatogram (GPC) of the polymer (G) was 30,000. The graft copolymer (G) had Fcalc / Ccalc = 0.80.

(Toner Production Example 1)
As a vinyl polymer unit component, 1.1 mol of styrene, 0.14 mol of 2-ethylhexyl acrylate, 0.1 mol of acrylic acid, and 0.05 mol of dicumyl peroxide are placed in a dropping funnel. As the polyester unit component, polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane 2.0 mol, polyoxyethylene (2.2) -2,2-bis (4-hydroxy) Phenyl) propane 0.8 mol, terephthalic acid 0.8 mol, trimellitic anhydride 0.6 mol, fumaric acid 1.5 mol and dibutyltin oxide 0.2 g were put into a 4-liter glass 4-necked flask, thermometer and stirred A rod, a condenser and a nitrogen inlet tube were installed and placed in a mantle heater. Next, after the inside of the flask was replaced with nitrogen gas, the temperature was gradually increased while stirring, and while stirring at a temperature of 145 ° C., the monomer of the vinyl resin, the crosslinking agent and the polymerization initiator were added from the previous dropping funnel. It was dripped over 4 hours. Next, the temperature was raised to 245 ° C. and reacted for 4 hours to obtain a resin A having a polyester unit. As the resin A, a resin having a weight average molecular weight of 80000 and a number average molecular weight of 3200 was obtained.
-Resin A 100 parts by mass-Paraffin wax (maximum endothermic peak temperature 78 ° C) 5 parts by mass-Aluminum compound 3,5-di-t-butylsalicylate 0.5 parts by mass I. Pigment Blue 15: 3 5 parts by mass The above-mentioned ingredients were mixed with a Henschel mixer (FM-75 type, manufactured by Mitsui Miike Chemical Co., Ltd.), and then a twin-screw kneader (PCM-30 type) set at a temperature of 130 ° C. And kneaded by Ikegai Iron Works Co., Ltd.). The obtained kneaded material was cooled and coarsely pulverized to 1 mm or less with a hammer mill to obtain a coarsely pulverized material. The obtained coarsely pulverized toner was pulverized using a collision-type airflow pulverizer using high-pressure gas. Further, the particles were classified by a multi-division classifier using the Coanda effect to obtain cyan particles. Surface modification was performed using a mechano-fusion system equipped with a cooling mechanism such as a chiller unit to obtain cyan particles having a weight average particle diameter of 6.5 μm.

  To 100 parts by mass of the obtained cyan particles, 1.0% by mass of titanium oxide fine particles having a primary average particle diameter of 50 nm surface-treated with isobutyltrimethoxysilane was added, and a Henschel mixer (FM-75 type, Mitsui Miike Chemical Industries ( And toner 1 was obtained. The transmittance (%) of the toner 1 in a 45 volume% methanol aqueous solution was 40%.

(Toner Production Example 2)
-Resin A 100 parts by mass-Polyethylene wax (maximum endothermic peak temperature 120 ° C) 5 parts by mass-Aluminum compound 3,5-di-t-butylsalicylate 0.5 parts by mass I. Pigment Blue 15: 3 5 parts by mass Toner 2 was obtained in the same manner as in Production Example 1 except that the kneading preset temperature of the material having the above formulation was changed to 150 ° C. The transmittance (%) of the toner 2 in a 45 volume% methanol aqueous solution was 65%.

(Toner Production Example 3)
As a polyester unit component, 3.6 mol of polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, polyoxyethylene (2.2) -2,2-bis (4-hydroxyphenyl) 1.6 mol of propane, 1.8 mol of terephthalic acid, 2.5 mol of dodecenyl succinic acid, 0.5 mol of trimetic anhydride and dibutyltin oxide were put into a 4-liter 4-neck flask made of 0.2 g glass, a thermometer, a stirring rod, a condenser, and A nitrogen inlet tube was installed and placed in the mantle heater. Under a nitrogen atmosphere, reaction was performed at 245 ° C. for 5 hours to obtain a resin B having a polyester unit. As the resin B, a resin having a weight average molecular weight of 50000 and a number average molecular weight of 3000 was obtained.
-Resin B 100 parts by mass-Polyethylene wax (maximum endothermic peak temperature 120 ° C) 5 parts by mass-Aluminum compound 3,5-di-t-butylsalicylate 0.5 parts by mass I. Pigment Blue 15: 3 5 parts by mass Toner 3 was obtained in the same manner as in Production Example 1 except that the kneading preset temperature of the material having the above formulation was changed to 150 ° C. The transmittance (%) of the toner 3 in a 45 volume% methanol aqueous solution was 75%.

(Toner Production Example 4)
-Resin A 100 parts by mass-Paraffin wax (maximum endothermic peak temperature 78 ° C) 3 parts by mass-3,5-di-t-butylsalicylic acid aluminum compound 1.0 part by mass-C.I. I. Pigment Blue 15: 3 4 parts by mass A material of the above formulation was obtained in the same manner as in Production Example 1 to obtain a toner crushed product, and the obtained crushed product was pulverized to have a weight average particle size of 7.5 μm. Without performing, cyan particles were obtained. To 100 parts by mass of the obtained cyan particles, 1.0 mass% of titanium oxide fine particles having a primary particle diameter of 50 nm surface-treated with isobutyltrimethoxysilane was added, and a Henschel mixer (FM-75 type, Mitsui Miike Chemical Co., Ltd.) was added. And toner 4 was obtained. The transmittance (%) of the toner 4 in a 45% by volume methanol aqueous solution was 15%.

(Toner Production Example 5)
-Resin A 100 mass parts-3,5-di-t-butylsalicylic acid aluminum compound 3.0 mass parts-C.I. I. Pigment Blue 15: 3 4 parts by mass Toner 5 was obtained in the same manner as in Production Example 4 except that the kneading preset temperature of the material having the above formulation was changed to 120 ° C. The transmittance (%) of the toner 5 in a 45% by volume methanol aqueous solution was 10%.

  Table 1 below shows the transmittance of toners 1 to 5 obtained.

<Example 1>
0.5 parts by mass of melamine resin (average particle size 0.2 μm in particle size distribution on a number basis), carbon black (average in particle size distribution on a number basis) with respect to 30 parts by mass of the graft copolymer (A) solution (Particle size 30 nm, DBP oil absorption 50 ml / 100 g) 1.0 part by mass and toluene 100 parts by mass are mixed well by a homogenizer. Next, the above coating solution was gradually added while stirring 1000 parts by mass of carrier core A while continuously applying shear stress, and the solvent was volatilized at 70 ° C. to perform resin coating on the carrier surface. The resin-coated magnetic carrier particles were heat-treated with stirring at 100 ° C. for 2 hours, rapidly cooled for 1 hour in a 10 ° C. constant temperature bath, crushed, classified with a sieve having an aperture of 76 μm, and number-based. In the particle size distribution, the average particle size is 35 μm, the true specific gravity is 3.6 g / cm ³ , the magnetization strength is 49 Am ² / kg, the specific resistance is 8 × 10 ⁸ Ω · cm, the specific surface area BET1 is 0.05 m ² / g, Fattom / Magnetic carrier 1 with Cat = 0.58 was obtained.

  To 90 parts by mass of the magnetic carrier 1, 10 parts by mass of toner 1 was added and mixed by a tumbler mixer to obtain a two-component developer 1.

  Using this developer, Canon CLC5000 modified full-color copier (with a reduced laser spot diameter and 600 dpi output, changing the surface of the fixing roller of the fixing unit to a PFA tube, and removing the oil coating mechanism) The image was evaluated in a high-temperature and high-humidity environment (30 ° C., 85% RH). The developing condition is that the developing sleeve and the photosensitive member are rotated in the forward direction in the developing region, the developing sleeve is set to 2.0 times the photosensitive member, Vd-600V, Vl-110V, Vdc-450V, Vpp 2 kV, frequency 1 8 kHz. The items for image evaluation and the evaluation criteria are shown below.

(1) Dot reproducibility A 30H image was formed using the toner and the remodeling machine, this image was visually observed, and the dot reproducibility of the image was evaluated based on the following criteria. The 30H image is a halftone image when 256 gradations are displayed in hexadecimal, 00H is solid white, and FFH is solid black.
A: Smooth and smooth.
B: I don't feel a lot of rustling.
C: Although there is a slight feeling of roughness, it is at a level where there is no practical problem.
D: There is a feeling of roughness and is a problem.
E: There is a very rough feeling.

(2) White spot evaluation White spot evaluation will be described with reference to FIGS. 3A, 3B, and 3C.

First, as shown in FIG. 3A, a chart in which halftone horizontal bands (30H width 10 mm) and solid black horizontal bands (FFH width 10 mm) are alternately arranged in the transfer direction of the transfer paper 3a is output. . FIG. 3B shows a cross-sectional view of the transfer paper 3a after the toner image is transferred, 3b shows toner, and 3c shows a white-out portion. The toner image is read by a scanner and binarized. FIG. 3C shows a luminance distribution (256 gradations) of a certain line in the carrying direction of the binarized image. In the luminance distribution of the line, 3d is a point where the amount of toner adhered in the halftone region is small, 3e is a point where the toner is not applied most due to white spots, and an extension line of luminance in the halftone area where white spots are not white When the intersection of the change point between the halftone area and the solid black area is 3f, the hatched area surrounded by the points 3d, 3e, and 3f is the brightness area of the white area, and the area of the hatched area (the number of brightness) Of white) and the degree of whiteout.
A: 50 or less Almost inconspicuous and very good.
B: 51 to 150 Good.
C: 151 to 300 There are white spots, but it is at a level where there is no practical problem.
D: 301 to 600 White spots are conspicuous, which is a problem.
E: 601 or more Very noticeable.

(3) Durability Evaluation of Carrier Coating Material The two-component developer used in the present invention is placed in a CLC5000 developer, and the developing sleeve is processed at high speed under high temperature and high humidity (40 ° C./80% RH). After idly rotating at a speed of 800 mm / sec, the two-component developer was sampled from the sleeve surface, the toner and the carrier were separated, and the carrier after idling was observed with a scanning electron microscope (SEM). A: The carrier surface is not changed at all B: The carrier surface is slightly changed, but there is no problem in practical use C: The toner is slightly fused D: The coating material is slightly peeled off E: The coating material is peeled off and toner fusion occurs. Table 2 shows the physical property values of the carrier produced in the present invention. Table 3 shows the results of (1) dot reproducibility, (2) white spot evaluation, and (3) durability evaluation of the carrier coating material of the two-component developer of the present invention.

<Example 2>
30 parts by mass of the graft copolymer (B) solution, 1.0 part by mass of melamine resin (average particle size 0.2 μm in particle size distribution based on number), carbon black (average in particle size distribution based on number) Particle size 15 nm, DBP oil absorption 100 ml / 100 g) 1.0 part by mass and 100 parts by mass of toluene are mixed well by a homogenizer. Subsequently, the above coating liquid was gradually added while stirring 1000 parts by mass of carrier core B while continuously applying shear stress, and the solvent was volatilized at 70 ° C. to perform resin coating on the carrier surface. The resin-coated magnetic carrier particles were heat-treated with stirring at 100 ° C. for 2 hours, rapidly cooled for 1 hour in a 10 ° C. constant temperature bath, crushed, classified with a sieve having an aperture of 76 μm, and number-based. In the particle size distribution, the average particle size is 50 μm, the true specific gravity is 3.6 g / cm ³ , the magnetization is 49 Am ² / kg, the specific resistance is 2 × 10 ⁹ Ω · cm, the specific surface area BET1 is 0.04 m ² / g, Fattom / A magnetic carrier 2 with Cat = 0.81 was obtained. The physical property values of the obtained carrier 2 are shown in Table 2.

  To 90 parts by mass of the magnetic carrier 2, 10 parts by mass of toner 1 was added and mixed by a tumbler mixer to obtain a two-component developer 2.

  Table 3 shows the results of (1) dot reproducibility, (2) white spot evaluation, and (3) durability evaluation of the carrier coating material.

<Example 3>
To 60 parts by mass of the graft copolymer (C) solution, 1.0 part by mass of melamine resin (average particle diameter 0.5 μm in particle size distribution on a number basis) and 100 parts by mass of toluene are mixed well by a homogenizer. Subsequently, the coating liquid was gradually added while stirring 1000 parts by mass of the carrier core C with continuous application of shear stress, and the solvent was volatilized at 70 ° C. to perform resin coating on the carrier surface. The resin-coated magnetic carrier particles were heat-treated with stirring at 100 ° C. for 2 hours, rapidly cooled for 1 hour in a 10 ° C. constant temperature bath, crushed, classified with a sieve having an aperture of 76 μm, and number-based. Average particle diameter in particle size distribution: 25 μm, true specific gravity: 3.6 g / cm ³ , magnetization strength: 61 Am ² / kg, specific resistance: 9 × 10 ⁷ Ω · cm, specific surface area BET1: 0.08 m ² / g, Fattom / A magnetic carrier 3 with Cat = 0.12 was obtained.

  To 90 parts by mass of the magnetic carrier 3, 10 parts by mass of the toner 1 was added and mixed by a tumbler mixer to obtain a two-component developer 3. Table 2 shows the physical property values of the magnetic carrier 3 obtained.

  Table 3 shows the results of (1) dot reproducibility, (2) white spot evaluation, and (3) durability evaluation of the carrier coating material.

<Comparative Example 1>
To 30 parts by mass of the graft copolymer (C) solution, 2.0 parts by mass of melamine resin (average particle size 0.5 μm in particle size distribution on the basis of number) and 100 parts by mass of toluene are mixed well by a homogenizer. Next, the above coating solution was gradually added while stirring 1,000 parts by mass of carrier core D while continuously applying shear stress, and the solvent was volatilized at 70 ° C. to perform resin coating on the carrier surface. The resin-coated magnetic carrier particles were heat-treated with stirring at 120 ° C. for 3 hours, quenched in a thermostatic bath at 10 ° C. for 1 hour, crushed, classified with a sieve having an aperture of 76 μm, and number-based. Average particle diameter in particle size distribution 50 μm, true specific gravity 5.0 g / cm ³ , magnetization strength 63 Am ² / kg, specific resistance 5 × 10 ⁶ Ω · cm, specific surface area BET1 0.12 m ² / g, Fattom / A magnetic carrier 4 with Cat = 0.13 was obtained. Table 2 shows the physical property values of the magnetic carrier 4 obtained.

  To 90 parts by mass of the magnetic carrier 4, 10 parts by mass of the toner 1 was added and mixed by a tumbler mixer to obtain a two-component developer 4.

  Table 3 shows the results of (1) dot reproducibility, (2) white spot evaluation, and (3) durability evaluation of the carrier coating material.

<Comparative example 2>
To 60 parts by mass of the graft copolymer (D) solution, 3.0 parts by mass of polymethyl methacrylate resin (average particle size 1.0 μm in particle size distribution on the basis of number) and 100 parts by mass of toluene are mixed well by a homogenizer. To do. Subsequently, the coating liquid was gradually added while stirring 1000 parts by mass of carrier core B while continuously applying shear stress, and the solvent was volatilized at 150 ° C. to coat the surface of the magnetic carrier. The resin-coated magnetic carrier particles were heat-treated with stirring at 100 ° C. for 2 hours, quenched in a thermostatic bath at 5 ° C. for 1 hour, crushed, classified with a sieve having an aperture of 76 μm, and number-based. Average particle diameter 50 μm in particle size distribution, true specific gravity 3.6 g / cm ³ , magnetization strength 49 Am ² / kg, specific resistance 5 × 10 ⁷ Ω · cm, specific surface area BET1 0.11 m ² / g, Fattom / Catom = 0.07 magnetic carrier 5 was obtained. The physical property values of the obtained carrier 5 are shown in Table 2.

  To 90 parts by mass of the magnetic carrier 5, 10 parts by mass of the toner 1 was added and mixed with a tumbler mixer to obtain a two-component developer 5.

  Table 3 shows the results of (1) dot reproducibility, (2) white spot evaluation, and (3) durability evaluation of the carrier coating material.

<Comparative Example 3>
For 60 parts by mass of the graft copolymer (E) solution, 2.0 parts by mass of melamine resin (average particle size 0.1 μm in particle size distribution on the number basis), carbon black (number average particle size 25 nm, DBP oil absorption) 150 ml / 100 g) 0.5 parts by mass and 100 parts by mass of toluene are mixed well by a homogenizer. Next, the above coating liquid was gradually added while stirring 1000 parts by mass of carrier core B while continuously applying shear stress, and the solvent was volatilized at 70 ° C. to perform resin coating on the magnetic carrier surface. The resin-coated magnetic carrier particles were heat-treated with stirring at 100 ° C. for 2 hours, quenched in a thermostatic bath at 5 ° C. for 1 hour, crushed, classified with a sieve having an aperture of 76 μm, and number-based. In the particle size distribution, the average particle size is 35 μm, the true specific gravity is 3.6 g / cm ³ , the magnetization is 49 Am ² / kg, the specific resistance is 5 × 10 ⁹ Ω · cm, the specific surface area BET1 is 0.05 m ² / g, Fattom / A magnetic carrier 6 having Cat = 0.87 was obtained. The physical property values of the obtained magnetic carrier 6 are shown in Table 2.

  To 90 parts by mass of the magnetic carrier 6, 10 parts by mass of the toner 1 was added and mixed by a tumbler mixer to obtain a two-component developer 6.

  Table 3 shows the results of (1) dot reproducibility, (2) white spot evaluation, and (3) durability evaluation of the carrier coating material.

<Example 4>
For 60 parts by mass of the graft copolymer (F) solution, 1.0 part by mass of polymethyl methacrylate resin (average particle size 1.0 μm in particle size distribution on the basis of number), carbon black (particle size distribution on the basis of number) In addition, 0.5 parts by mass of an average particle diameter of 15 nm and a DBP oil absorption of 100 ml / 100 g), 50 parts by mass of toluene, and 50 parts by mass of methyl ethyl ketone are mixed well by a homogenizer. Subsequently, the coating liquid was gradually added while stirring 1000 parts by mass of carrier core B while continuously applying shear stress, and the solvent was volatilized at 50 ° C. to coat the surface of the magnetic carrier. The resin-coated magnetic carrier particles were heat-treated with stirring at 120 ° C. for 2 hours, quenched in a thermostatic bath at 5 ° C. for 1 hour, crushed, classified with a sieve having an opening of 76 μm, and number-based. In the particle size distribution, the average particle size is 35 μm, the true specific gravity is 3.6 g / cm ³ , the magnetization is 49 Am ² / kg, the specific resistance is 5 × 10 ⁹ Ω · cm, the specific surface area BET1 is 0.07 m ² / g, Fattom / A magnetic carrier 7 with Catom = 0.61 was obtained. The physical property values of the obtained magnetic carrier 7 are shown in Table 2.

  To 90 parts by mass of the magnetic carrier 7, 10 parts by mass of the toner 1 was added and mixed with a tumbler mixer to obtain a two-component developer 7.

  Table 3 shows the results of (1) dot reproducibility, (2) white spot evaluation, and (3) durability evaluation of the carrier coating material.

< Reference Example 1 >
Homogenizer for 60 parts by mass of polymer (G) solution, 1.0 part by mass of melamine resin (average particle size 0.3 μm in particle size distribution on number basis), 0.5 parts by mass of carbon black, and 100 parts by mass of toluene Mix better. Subsequently, the coating liquid was gradually added while stirring 1000 parts by mass of carrier core B while continuously applying a shear stress, and the solvent was volatilized at 50 ° C. to perform resin coating on the carrier surface. The resin-coated magnetic carrier particles were heat-treated with stirring at 120 ° C. for 2 hours, quenched in a thermostatic bath at 5 ° C. for 1 hour, crushed, classified with a sieve having an opening of 76 μm, and number-based. In the particle size distribution, the average particle size is 35 μm, the true specific gravity is 3.6 g / cm ³ , the magnetization strength is 49 Am ² / kg, the specific resistance is 1 × 10 ⁹ Ω · cm, the specific surface area BET1 is 0.05 m ² / g, Fattom / A magnetic carrier 8 with Cat = 0.83 was obtained. Table 2 shows the physical property values of the magnetic carrier 8 obtained.

  To 90 parts by mass of the magnetic carrier 8, 10 parts by mass of the toner 1 was added and mixed by a tumbler mixer to obtain a two-component developer 8.

  Table 3 shows the results of (1) dot reproducibility, (2) white spot evaluation, and (3) durability evaluation of the carrier coating material.

<Comparative example 4>
0.5 parts by mass of melamine resin (average particle size 0.3 μm in particle size distribution on a number basis), 1.0 part by mass of carbon black, 100 parts by mass of toluene with respect to 10 parts by mass of the graft copolymer (D) solution Mix well with a homogenizer. Subsequently, the coating liquid was gradually added while stirring 1000 parts by mass of carrier core D while continuously applying shear stress, and the solvent was volatilized at 100 ° C. to coat the surface of the magnetic carrier. The resin-coated magnetic carrier particles were heat-treated with stirring at 90 ° C. for 2 hours, quenched in a thermostatic bath at 5 ° C. for 1 hour, crushed, classified with a sieve having an aperture of 76 μm, and number-based. In the particle size distribution, the average particle size is 35 μm, the true specific gravity is 3.6 g / cm ³ , the magnetization strength is 63 Am ² / kg, the specific resistance is 1 × 10 ⁶ Ω · cm, the specific surface area BET1 is 0.10 m ² / g, Fattom / A magnetic carrier 9 with Cat = 0.11 was obtained. Table 2 shows the physical property values of the magnetic carrier 9 obtained.

  To 90 parts by mass of the magnetic carrier 9, 10 parts by mass of the toner 1 was added and mixed by a tumbler mixer to obtain a two-component developer 9.

  Table 3 shows the results of (1) dot reproducibility, (2) white spot evaluation, and (3) durability evaluation of the carrier coating material.

<Example 6>
0.5 parts by mass of melamine resin (average particle size 0.3 μm in particle size distribution on a number basis), 0.5 parts by mass of carbon black, 100 parts by mass of toluene with respect to 30 parts by mass of the graft copolymer (C) solution Mix well with a homogenizer. Subsequently, the coating liquid was gradually added while stirring 1000 parts by mass of carrier core B while continuously applying a shear stress, and the solvent was volatilized at 100 ° C. to perform resin coating on the surface of the magnetic carrier. The resin-coated magnetic carrier particles were heat-treated with stirring at 90 ° C. for 2 hours, quenched in a thermostatic bath at 15 ° C. for 1 hour, crushed, classified with a sieve having an aperture of 76 μm, and number-based. In the particle size distribution, the average particle size is 35 μm, the true specific gravity is 3.6 g / cm ³ , the magnetization is 49 Am ² / kg, the specific resistance is 3 × 10 ⁹ Ω · cm, the specific surface area BET1 is 0.09 m ² / g, Fattom / A magnetic carrier 10 with Cat = 0.09 was obtained. The physical property values of the obtained carrier 10 are shown in Table 2.

  To 90 parts by mass of the magnetic carrier 10, 10 parts by mass of the toner 1 was added and mixed by a tumbler mixer to obtain a two-component developer 10.

  Table 3 shows the results of (1) dot reproducibility, (2) white spot evaluation, and (3) durability evaluation of the carrier coating material.

< Reference Example 2 >
To 90 parts by mass of the magnetic carrier 8, 10 parts by mass of the toner 2 was added and mixed by a tumbler mixer to obtain a two-component developer 11.

  Table 3 shows the results of (1) dot reproducibility, (2) white spot evaluation, and (3) durability evaluation of the carrier coating material.

<Comparative Example 5>
To 90 parts by mass of the magnetic carrier 8, 10 parts by mass of the toner 3 was added and mixed by a tumbler mixer to obtain a two-component developer 12.

  Table 3 shows the results of (1) dot reproducibility, (2) white spot evaluation, and (3) durability evaluation of the carrier coating material.

<Example 8>
To 90 parts by mass of the magnetic carrier 7, 10 parts by mass of the toner 2 was added and mixed by a tumbler mixer to obtain a two-component developer 13.

  Table 3 shows the results of (1) dot reproducibility, (2) white spot evaluation, and (3) durability evaluation of the carrier coating material.

<Comparative Example 6>
To 90 parts by mass of the magnetic carrier 7, 10 parts by mass of the toner 3 was added and mixed by a tumbler mixer to obtain a two-component developer 14.

  Table 3 shows the results of (1) dot reproducibility, (2) white spot evaluation, and (3) durability evaluation of the carrier coating material.

<Example 9>
To 90 parts by mass of the magnetic carrier 7, 10 parts by mass of the toner 4 was added and mixed by a tumbler mixer to obtain a two-component developer 15.

  Table 3 shows the results of (1) dot reproducibility, (2) white spot evaluation, and (3) durability evaluation of the carrier coating material.

<Example 10>
To 90 parts by mass of the magnetic carrier 7, 10 parts by mass of the toner 5 was added and mixed by a tumbler mixer to obtain a two-component developer 16.
Table 3 shows the results of (1) dot reproducibility, (2) white spot evaluation, and (3) durability evaluation of the carrier coating material.

It is a schematic sectional drawing of the apparatus which measures the specific resistance of the magnetic carrier of this invention, a magnetic microparticle, and a nonmagnetic inorganic compound microparticle. It is the schematic which shows the state of the blank in this invention. It is the schematic which shows white spot evaluation in this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Lower electrode 12 Upper electrode 13 Insulator 14 Ammeter 15 Voltmeter 16 Constant voltage device 17 Carrier 18 Guide ring d Sample thickness E Resistance measuring cell 21 Transfer material 22 Toner layer A White part B Sweep part 3a Transfer paper 3b Toner Layer 3c White spot 3d The amount of toner paste in the halftone area is reduced 3e The toner is not applied most due to white spot 3f The luminance extension line and the halftone area in the halftone area without white spot Intersection with change point with solid black area

Claims (7)

In a two-component developer containing a toner and a magnetic carrier,
The toner has toner particles containing a binder resin, a release agent, and a colorant,
The transmittance of light having a wavelength of 600 nm with respect to a dispersion obtained by dispersing the toner in an aqueous solution of 45% by volume of methanol is 10 to 70%,
Magnetic carrier is a magnetic carrier obtained by coating the coating material having at least a magnetic fine particles, the coating resin to the surface of the magnetic fine particle dispersed resin core containing a binder resin,
The ratio of the fluorine element abundance (Fatom) to the carbon element abundance (Catom) (Fatom / Catom) on the surface of the magnetic carrier is 0.10 to 0.85,
The ratio (Fatom / Catom) of the fluorine element abundance ratio (Fatom) to the carbon element abundance ratio (Catom) on the surface of the magnetic carrier,
Fluorine element abundance ratio that can be calculated theoretically from the molecular structure of the coating resin carbon element abundance ratio (Fcalc) the ratio of the ratio (Fcalc / Ccalc) for (Ccalc) (Fatom / Catom) / (Fcalc / Ccalc) is 1. A two-component developer characterized by being 10 to 2.00 . 2. The two-component developer according to claim 1, wherein the specific resistance of the magnetic carrier is 1 × 10 ^{7 to} 1 × 10 ¹¹ (Ω · cm). 3. The two-component development according to claim 1, wherein a specific surface area BET1 (m ² / g) of the magnetic carrier according to the BET method is 0.02 to 0.20 (m ² / g). Agent . A said magnetic fine particle dispersed resin The specific surface area BET 2 by the BET method of the core 0.03 to 0.20 ^(m 2 / g), the specific surface area BET1 and specific surface area BET 2, characterized by satisfying BET1 <BET 2 The two-component developer according to claim 3 . The coating resin is

[Wherein, m represents an integer of 5 to 9. ]
The two-component development according to any one of claims 1 to 4 , which is a polymer or copolymer composed of a methacrylic acid ester unit or an acrylic acid ester unit having a perfluoroalkyl unit represented by Agent . The coating resin is

[Wherein, Z represents a hydrogen atom or an alkyl group, m represents an integer of 1 to 20, and n represents an integer of 1 to 10. ]
Two-component developer according to any one of claims 1 to 4, characterized in that a polymer or copolymer composed of units represented in. The two-component developer according to any one of claims 1 to 6 , wherein the amount of the coating material is 0.3 to 4.0 parts by mass with respect to 100 parts by mass of the magnetic material-dispersed resin core.

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