JP5350137B2 - Magnetic toner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a toner having excellent durability and stability with less fogging, which can avoid formation of a stop stripe and cleaning failure. <P>SOLUTION: The magnetic toner which contains a binding resin, magnetic toner particles containing at least a magnetic body, and a fatty acid metal salt has a fatty acid metal salt content of 0.05-0.50 pts.mass per 100 pts.mass of the magnetic toner particles. The median diameter (D50) of the fatty acid metal salt based on volume is 0.15-0.65 &mu;m; the compressibility of the magnetic toner obtained by formula (1): compressibility=ä1-(apparent density/tap density)}&times;100 is 30 or less; and the surface free energy of the magnetic toner is 40.0 mJ/m<SP>2</SP>or less. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a magnetic toner used in a recording method using electrophotography or the like.

  In recent years, printers and copiers have been shifting from analog to digital, and there is a strong demand for consistently high image quality in various environments as well as excellent reproducibility of latent images and high resolution.

  Here, focusing on the various environments, it has been found that a specific problem occurs in a specific environment / condition. After being left overnight in a high-temperature and high-humidity environment, the electrostatic latent image carrier period There was a problem that white streak-like image defects occurred.

  It has been found that this is caused by a unique phenomenon in the contact portion between the electrostatic image carrier and the cleaning blade.

  Considering the behavior of the electrostatic latent image carrier and the cleaning blade during printing, the transfer residual toner and the external additive are accumulated at the tip of the cleaning blade by overlapping a large number of prints. Such transfer residual toner and external additives are pressed against the electrostatic latent image carrier by the pressure of the contact portion of the cleaning blade when printing is stopped, causing fusion. Further, when the electrostatic latent image carrier once stopped is rotated, the friction coefficient between the cleaning blade and the electrostatic latent image carrier is higher than that during rotation, so that the cleaning blade is easily chattered. For this reason, when printing is performed again, the cleaning blade chatters, and the fused material generated at the contact portion slips through the cleaning blade. In this state, when the electrostatic latent image carrier rotates once and the fused material comes into contact with the cleaning blade, the rotation between the electrostatic latent image carrier and the cleaning blade is inhibited. It causes a decline in sex. Whenever the electrostatic latent image carrier is rotated twice or three times, image defects due to charging defects are caused for each rotation cycle of the electrostatic latent image carrier due to the same cause. This is considered to be the cause of a white streak-like image defect (hereinafter referred to as a stop streak).

  On the other hand, it is required to adjust the contact pressure of the cleaning blade in order to suppress the generation of a fused product when printing is stopped. However, when the contact pressure is light, the stop streak is improved, but cleaning failure occurs in a low temperature environment, and it is very difficult to balance the two.

  On the other hand, it is known to use a so-called solid soap such as a fatty acid metal salt or a solid lubricant for the purpose of improving cleaning (see Patent Documents 1 and 2). There has also been proposed a toner in which a 50% volume diameter of the toner and a glass transition temperature are controlled and a fatty acid metal salt particle and a fluidity improver are added (see Patent Document 3).

  However, even if these toners are used, it is difficult to achieve both stop streaking and cleaning, and there is room for improvement. Furthermore, when these fatty acid metal salts are used in an image forming apparatus using a small-diameter toner carrier, so-called fogging, in which toner also flies to non-image areas, is likely to be studied.

  Further, in terms of releasability from members, it is important to control the contact angle and surface free energy, and toners that define these have been proposed (see Patent Documents 4 and 5). However, these toners have no description regarding cleaning and stop stripes, and there is room for further study.

JP 63-096664 A Japanese Patent Laid-Open No. 04-177364 JP 09-251214 A JP 2000-047428 A JP 2009-109817 A

  An object of the present invention has been made in view of the above-described problems of the prior art, and is to provide a toner having excellent durability and stability with less fogging and no streaking or cleaning failure.

The present invention is a magnetic toner containing magnetic toner particles containing at least a binder resin and a magnetic material, and a fatty acid metal salt,
The fatty acid metal salt is contained in an amount of 0.05 to 0.50 parts by mass with respect to 100 parts by mass of the magnetic toner particles.
Median diameter in volume-based of the fatty acid metal salt (D50) is, is at 0.15μm or 0.65μm or less,
The magnetic toner has a compression ratio obtained from the following formula (1) of 30 or less,
Formula (1) Compression rate = {1− (apparent density / tap density)} × 100
The magnetic toner has a surface free energy of 40.0 mJ / m ² or less.

  According to the present invention, it is possible to obtain an excellent image with less fogging without causing stop streaks and poor cleaning through durability.

FIG. 2 is a schematic cross-sectional view illustrating an example of an image forming apparatus that can suitably use the toner of the present invention.

The toner of the present invention is a magnetic toner containing magnetic toner particles containing at least a binder resin and a magnetic material, and a fatty acid metal salt,
The fatty acid metal salt is contained in an amount of 0.05 to 0.50 parts by mass with respect to 100 parts by mass of the magnetic toner particles.
Median diameter in volume-based of the fatty acid metal salt (D50) is, is at 0.15μm or 0.65μm or less,
The magnetic toner has a compression ratio obtained from the following formula (1) of 30 or less,
Formula (1) Compression rate = {1− (apparent density / tap density)} × 100
The magnetic toner has a surface free energy of 40.0 mJ / m ² or less.

  As described above, the stop streaks are as follows: 1) The toner and the external additive are compressed at the contact portion between the cleaning blade and the electrostatic latent image carrier, and left to stand for a long time. 2) At the start of printing, the cleaning blade chatters, and the fused material slips through the cleaning blade; 3) When the slipped fused material comes into contact with the cleaning blade again, rotation of the electrostatic latent image carrier is inhibited. Occurs.

  As a result of extensive studies by the present inventors based on these mechanisms, a fatty acid metal salt having a specific particle diameter is contained, and by adjusting the compression ratio and surface free energy of the toner, it is possible to improve stop streaks without causing poor cleaning. As a result, they have found the present invention.

  First, regarding the fatty acid metal salt, the toner of the present invention contains a fatty acid metal salt having a median diameter (D50) on a volume basis of 0.15 μm to 0.65 μm. In general, the external additive having a large particle diameter is less likely to adhere to the toner particles and easily separate from the toner particle diameter. In particular, fatty acid metal salts have a slippery property, so this tendency is strong. For this reason, the conventional fatty acid metal salt has a large particle size and is difficult to behave together with the toner. However, in the present invention, the toner can behave together with the fatty acid metal salt by setting the median diameter (D50) on the volume basis of the fatty acid metal salt to 0.15 μm or more and 0.65 μm or less. This is because the particle diameter of the fatty acid metal salt is sufficiently small with respect to the toner, so that it can be uniformly adhered to the toner, and is not detached from the toner during development and transfer.

  By containing such a fatty acid metal salt in an amount of 0.05 part by mass or more and 0.50 part by mass or less per 100 parts by mass of toner particles, chattering of the cleaning blade can be highly suppressed. This is because a sufficient amount of the fatty acid metal salt is uniformly adhered to the transfer residual toner, and the fatty acid metal salt can be applied to the electrostatic latent image carrier in the cleaning unit. . In addition, since the fatty acid metal salt is uniformly attached to the toner, chattering of the cleaning blade can be suppressed to a high level through durability.

  If the amount of the fatty acid metal salt is less than 0.05 parts by mass, the above effect cannot be obtained. On the other hand, when the amount of the fatty acid metal salt is more than 0.50 parts by mass, the developability of the toner is lowered (that is, the density is lowered) and fog is increased, which is not preferable.

  When the median diameter (D50) on the volume basis of the fatty acid metal salt is larger than 0.65 μm, the fatty acid metal salt hardly adheres uniformly to the toner and behaves in a free state. In such a state, it is difficult to stably supply the fatty acid metal salt to the cleaning unit, and it is difficult to highly suppress chatter of the cleaning blade, which is not preferable.

  Further, when the median diameter (D50) on the volume basis of the fatty acid metal salt is smaller than 0.15 μm, the toner is easily covered uniformly, but the chargeability of the toner is hindered and development becomes difficult. For this reason, a decrease in image density and an increase in fog occur, which is not preferable.

  As described above, in the present invention, it is important that the median diameter (D50) on the volume basis of the fatty acid metal salt is 0.15 μm or more and 0.65 μm or less, more preferably 0.30 μm or more and 0.60 μm or less. . In addition, it is important for the amount of the fatty acid metal salt to be 0.05 parts by mass or more and 0.50 parts by mass or less per 100 parts by mass of the toner particles in order to highly suppress chatter of the cleaning blade.

Next, the toner of the present invention has a compression ratio obtained by the following formula (1) of 30% or less.
Formula (1) Compression rate = {1− (apparent density / tap density)} × 100

  A compression ratio of 30% or less means that the toner is difficult to be compressed even when pressure is applied, and the toner is hardly compressed even at the contact portion between the cleaning blade and the electrostatic latent image carrier, and the fused material is not compressed. It is unlikely to occur. For this reason, generation | occurrence | production of the 1st stage fusion | melting material which is a generation | occurrence | production factor of a stop streak can be inhibited. On the other hand, if the compression rate is larger than 30%, the toner present in the contact portion is compressed with high density, and it is not preferable because a fused material is easily generated.

  The compression rate can be controlled by the shape of the toner and the adhesion state of the external additive. Specifically, the compression ratio tends to be lowered by eliminating the unevenness on the toner surface and making it smooth, or increasing the circularity of the toner. In addition, the compression rate is lowered by increasing the fluidity of the toner.

The toner of the present invention has a surface free energy of 40.0 mJ / m ² or less. In general, a low surface free energy means that the releasability from other substances is good. In the present invention, since the surface free energy of the toner is 40.0 mJ / m ² or less, even if a fused product is generated at the contact portion between the cleaning blade and the electrostatic latent image carrier, the electrostatic latent image carrier Is considered to be scraped off with a cleaning blade after one round. This is because the adhesion between the fused material and the electrostatic latent image carrier is low.

For this reason, rotation inhibition of the electrostatic latent image carrier is unlikely to occur. On the other hand, when the surface free energy of the toner is larger than 40.0 mJ / m ^{2, the} releasability between the fused material and the electrostatic latent image carrier is inferior, and the fused material is difficult to be scraped off by the cleaning blade. This is not preferable because rotation of the latent image carrier is inhibited.

  The surface free energy of the toner can also be controlled by the composition of the toner surface, the type of external additive, and the like. Specifically, the surface free energy can be lowered by not exposing the release agent or the highly water-absorbing compound to the toner surface. For this reason, the toner preferably has a core-shell structure, and a toner obtained in an aqueous medium can be suitably used because such a structure can be easily controlled. Further, as the external additive, a highly releasable material such as a fatty acid metal salt essential for the present invention is used, and the surface free energy of the toner can be lowered by uniformly adhering to the toner surface.

As described so far, for the three processes of generating stop streaks, 1) making the toner compression rate 30% or less makes fusion difficult; 2) fatty acid metal having a specific particle size in the toner By containing a specific amount of salt, chattering of the cleaning blade is highly suppressed; 3) By setting the surface free energy of the toner to 40.0 mJ / m ² or less, the fusion product and the electrostatic latent image carrier Stop streaks can be greatly improved only by taking measures at each stage to reduce adhesion and prevent rotation of the cleaning blade from being hindered.

  Further, the toner of the present invention can greatly improve the cleaning property. This is because, as described above, chattering of the cleaning blade can be highly suppressed, and the following points are effective.

First, since the surface free energy of the toner of the present invention is as low as 40.0 mJ / m ² or less, the adhesion between the transfer residual toner and the electrostatic latent image carrier is sufficiently low. For this reason, it becomes easy for the cleaning blade to scrape off the transfer residual toner.

  In addition, since the toner of the present invention has a low compression rate of 30% or less, it is difficult for the toner to enter the wedge-shaped portion between the cleaning blade and the electrostatic latent image carrier. These three synergistic effects enable stable cleaning through durability in various environments.

  In the toner of the present invention, the liberation rate of the fatty acid metal salt is preferably 10.0% by mass or more and 40.0% by mass or less. The fact that the liberation rate of the fatty acid metal salt is 40.0% by mass or less means that many fatty acid metal salt particles behave together with the toner, and it becomes possible to further suppress chattering of the cleaning blade, Is preferred. Moreover, since the fatty acid metal salt functions like a microcarrier when the liberation ratio of the fatty acid metal salt is 10.0% by mass or more, it is preferable.

  The toner of the present invention is obtained by mixing toner particles and a fatty acid metal salt, but it is preferable to control the mixing conditions in order to make the liberation rate of the fatty acid metal salt as described above. Specifically, it is effective to provide a pause step in the mixing step of mixing the toner particles and the fatty acid metal salt. By providing a pause process and dividing the mixing process into several times, the time during which the difference in the kinetic speed between the toner particles and the fatty acid metal salt occurs can be made longer than when the normal mixing process is performed. As a result, the homogenization of the fatty acid metal salt on the toner particle surface is further advanced. Further, by repeating the pause step and the mixing step in this manner, the fatty acid metal salt can be efficiently attached to the toner particle surface, and the release rate is suppressed while suppressing the loss of the fatty acid metal salt due to excessive stress. Can be controlled within the above range.

  It is preferable that the peripheral speed at the tip of the stirring blade in the mixing step be in the range of 30.0 m / sec to 50.0 m / sec. Within this range, the energy received from the stirring blade can be reduced to a level that does not cause rapid heat generation. When the peripheral speed at the leading edge of the stirring blade is within the above range, liberation of the fatty acid metal salt can be suppressed without deteriorating the toner particles and the fatty acid metal salt.

  As described above, the temperature in the tank during the mixing step is preferably set to 42 ° C. or lower in order to suppress the deterioration of the fatty acid metal salt, the toner particles, and the toner.

The fatty acid metal salt used in the present invention preferably has a span value B defined by the following formula (2) of 1.75 or less, more preferably 1.35 or less.
Formula (2) Span value B = (D95-D5) / D50
D5: 5% cumulative diameter based on volume of fatty acid metal salt D50: 50% cumulative diameter based on volume of fatty acid metal salt D95: 95% cumulative diameter based on volume of fatty acid metal salt

  The span value B is an index indicating the particle size distribution of the fatty acid metal salt, and the fact that the span value B is 1.75 or less means that the dispersion of the particle size of the fatty acid metal salt is small. As described above, in the present invention, it is preferable that the fatty acid metal salt is uniformly attached to the toner, but if the particle size of the fatty acid metal salt is uniform, the effect becomes larger and more effective. For this reason, when the span value B is 1.75 or less, the stop stripe and the cleaning property are improved. Further, since the fatty acid metal salt is uniformly attached to the toner particles, the toner charge amount distribution is also sharp and the fog is improved.

  The fatty acid metal salt used in the present invention is preferably a metal salt selected from zinc, calcium, magnesium, aluminum and lithium. Among these, fatty acid zinc or fatty acid calcium is particularly preferable, and when these are used, the effect of the present invention becomes more remarkable.

  Further, the fatty acid of the aliphatic metal salt is preferably a higher fatty acid having 12 to 22 carbon atoms. When fatty acids having 12 or more carbon atoms are used, it is easy to suppress the generation of free fatty acids. If the fatty acid has 22 or less carbon atoms, the melting point of the fatty acid metal salt does not become too high, and good fixability is easily obtained. As the fatty acid, stearic acid is particularly preferable.

  The toner of the present invention has a core-shell structure, and the shell layer preferably contains a polyester resin. By containing a polyester resin in the shell layer, the concentration is stabilized throughout the durability, and good cleaning properties can be maintained even in the latter half of the durability. Although it is about this reason, while having a core-shell structure, exposure of the coloring agent of a core can be suppressed, and exudation of a mold release agent etc. can be suppressed. As a result, high development efficiency can be maintained even in the latter half of the durability.

  Further, by including a polyester resin in the shell layer, the compatibility with the fatty acid metal salt which is an essential requirement of the present invention is improved, and a stable and uniform adhesion state can be maintained even in the latter half of the durability. As a result, good cleaning performance can be maintained even in the latter half of the durability, and the stop streak is also improved.

  In the present invention, the glass transition point (Tg) of the polyester resin contained in the shell layer is preferably 75 ° C. or higher and 90 ° C. or lower. When the glass transition point (Tg) of the polyester resin is 75 ° C. or higher, toner deterioration can be suppressed, and durability is improved. Further, since the glass transition point (Tg) of the shell layer is high, even if the toner is compressed at the contact portion between the cleaning blade and the electrostatic latent image carrier, it is difficult to produce a fused product. For this reason, the stop streak is less likely to occur and is more preferable.

  Moreover, when the glass transition point (Tg) of a polyester resin is lower than 90 degreeC, it becomes easy to control the liberation rate of a fatty-acid metal salt and the liberation rate of another external additive, and is preferable.

  As the polyester resin used in the toner of the present invention, a saturated polyester resin, an unsaturated polyester resin, or both can be appropriately selected and used.

  As the polyester resin used in the present invention, a normal resin composed of an alcohol component and an acid component can be used, and both components are exemplified below.

  As alcohol components, ethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, diethylene glycol, triethylene glycol, 1,5-pentanediol, 1,6-hexane Diol, neopentyl glycol, 2-ethyl-1,3-hexanediol, cyclohexanedimethanol, butenediol, octenediol, cyclohexenedimethanol, hydrogenated bisphenol A, and bisphenol derivatives represented by the following formula (I);

［式中、Ｒはエチレンまたはプロピレン基であり、ｘ，ｙはそれぞれ１以上の整数であり、かつｘ＋ｙの平均値は２から１０である。］、あるいは式（Ｉ）の化合物の水添物、また、下記式（ＩＩ）で示されるジオール；

[Wherein, R is an ethylene or propylene group, x and y are each an integer of 1 or more, and the average value of x + y is 2 to 10. Or a hydrogenated product of the compound of formula (I), and a diol represented by the following formula (II);

あるいは式（ＩＩ）の化合物の水添物のジオールが挙げられる。

Or the diol of the hydrogenated compound of the compound of a formula (II) is mentioned.

  In particular, the polyester resin in the present invention is preferably a polyester obtained by condensation polymerization of an alcohol component containing a propylene oxide adduct of bisphenol A and a carboxylic acid component.

  Furthermore, it is particularly preferable that 80 mol% or more, more preferably 90 mol% or more of the alcohol monomer unit of the polyester resin is a propylene oxide adduct of bisphenol A (average number of added moles = 2 mol).

  When 80 mol% or more of the alcohol monomer units are propylene oxide adducts of bisphenol A (average addition mole number = 2 mol), the polyester resin covers the toner surface as a more uniform shell layer. This is because the structure of the polyester resin constituting the shell is simple, and the composition is likely to be uniform as compared with the polyester resin having a complicated structure / structure. For this reason, the uniformity of the shell is improved, and the durability, the cleaning property, and the stop stripe as described above are improved.

  As the divalent carboxylic acid, benzene dicarboxylic acid such as phthalic acid, terephthalic acid, isophthalic acid, phthalic anhydride or the anhydride thereof; alkyl dicarboxylic acid such as succinic acid, adipic acid, sebacic acid, azelaic acid or the anhydride, Further, succinic acid substituted with an alkyl or alkenyl group having 6 to 18 carbon atoms or an anhydride thereof; unsaturated dicarboxylic acid such as fumaric acid, maleic acid, citraconic acid, itaconic acid or the anhydride thereof may be used.

  In addition, polyhydric alcohols such as glycerin, pentaerythritol, sorbit, sorbitan, and oxyalkylene ethers of novolac type phenol resins can be cited as the alcohol component, and trimellitic acid, pyromellitic acid, 1,2,3,4- Examples thereof include polyvalent carboxylic acids such as butanetetracarboxylic acid, benzophenonetetracarboxylic acid and anhydrides thereof.

  In the polyester resin of the present invention, it is preferable that 45 mol% to 55 mol% of all components are alcohol components, and 55 mol% to 45 mol% are acid components.

  The polyester resin in the present invention uses any catalyst such as a commonly used catalyst, for example, a metal such as tin, titanium, antimony, manganese, nickel, zinc, lead, iron, magnesium, calcium, germanium; and these metal-containing compounds. Can also be manufactured. Among these catalysts, a polyester resin polycondensed using a titanium-based catalyst is particularly preferable.

  Polyester resin polycondensed using a titanium-based catalyst tends to be a homogeneous polyester resin, and therefore, variation among toner particles is reduced. For this reason, the suspension polymerization method, which is a preferred method for producing the toner of the present invention, is very preferable because the outer shell of the toner particles can be easily covered uniformly.

Moreover, the polyester resin in the present invention preferably has a peak top molecular weight of 2.5 × 10 ³ or more and 2.5 × 10 ⁴ or less, more preferably 2.5 × 10 ³ or more and 1 obtained by GPC measurement. It is 5 × 10 ⁴ or less. When the peak top molecular weight is 2.5 × 10 ³ or more, developability, blocking resistance and durability are improved. A peak top molecular weight of 2.5 × 10 ⁴ or less is preferable because the low-temperature fixability is improved.

  The polyester resin in the present invention preferably has an acid value of 1 mgKOH / g or more and 15 mgKOH / g or less from the viewpoint of charging stability. When it is 15 mgKOH / g or less, the chargeability of the toner is easily stabilized, so that the developability particularly in a high temperature and high humidity environment is easily improved. Moreover, it is easy to form a uniform shell layer by being 1 mgKOH / g or more.

  In this invention, it is preferable that content of the polyester resin with respect to 100 mass parts of binder resin is 1 mass part or more and 30 mass parts or less, More preferably, it is 2 mass parts or more and 20 mass parts or less. When the content of the polyester resin is 2 parts by mass or more and 30 parts by mass or less, it is easy to achieve high dispersibility of materials such as a wax component and a colorant component in the toner, and at the same time, it is compatible with fixability at a light pressure. Easy to make.

  As a specific method for forming the shell layer from the polyester resin, it is possible to embed shell fine particles in the core particles. Further, when the toner is produced in an aqueous medium, which is a production method suitable for the present invention, it is possible to form a shell layer by attaching ultrafine particles for shells to core particles and drying them. In the dissolution suspension method and suspension polymerization method, the acid value and hydrophilicity of the polyester resin for the shell layer are utilized to make the polyester layer unevenly distributed at the interface with water, that is, near the toner surface, thereby forming a shell layer. Things are possible. Furthermore, a shell layer can be formed by swelling a monomer on the surface of the core particle by a so-called seed polymerization method and polymerizing the monomer.

  The weight average particle diameter (D4) of the toner of the present invention is preferably 3.0 μm or more and 12.0 μm or less, and more preferably 4.0 μm or more and 10.0 μm or less. When the weight average particle diameter (D4) is 3.0 μm or more and 12.0 μm or less, good fluidity can be obtained and development can be performed faithfully to the latent image. For this reason, a good image excellent in dot reproducibility can be obtained.

  The toner of the present invention preferably has an average circularity of 0.960 or more, and more preferably a mode circularity of 0.97 or more. When the average circularity of the toner is 0.960 or more, the toner has a spherical shape or a shape close to it, and it is easy to obtain a uniform triboelectric chargeability with excellent fluidity. For this reason, it is preferable because high developability is easily maintained even in the latter half of the durability.

  The glass transition temperature (Tg) of the toner of the present invention is preferably 40.0 ° C. or higher and 70.0 ° C. or lower. When the glass transition temperature is 40.0 ° C. or higher and 70.0 ° C. or lower, storage stability and durability can be improved while maintaining good fixability.

  As the binder resin used in the toner of the present invention, all known resins can be used, but styrene-acrylic resins are particularly preferable in terms of development characteristics, fixing properties and the like.

  In the toner of the present invention, a charge control agent may be blended as necessary to improve charging characteristics. As the charge control agent, a known one can be used, but a charge control agent that has a high charging speed and can stably maintain a constant charge amount is particularly preferable. Further, when the toner is produced using a polymerization method as described later, a charge control agent having a low polymerization inhibitory property and substantially free of soluble matter in an aqueous dispersion medium is particularly preferable. Among the charge control agents, specific examples of negative charge control agents include metal compounds of aromatic carboxylic acids such as salicylic acid, alkyl salicylic acid, dialkyl salicylic acid, naphthoic acid, dicarboxylic acid, azo dyes or metal salts of azo pigments or Examples thereof include a metal complex, a polymer compound having a sulfonic acid or carboxylic acid group in the side chain, a boron compound, a urea compound, a silicon compound, and a calixarene.

  As a method for adding a charge control agent to the toner, a method of adding the charge control agent to the inside of the toner particles, and in the case of producing the toner by suspension polymerization, the charge control agent is added to the polymerizable monomer composition before granulation. A method of adding is generally used. Also, during the polymerization by forming oil droplets in water, or after polymerization, seed polymerization is carried out by adding a polymerizable monomer in which the charge control agent is dissolved and suspended, and the toner surface is made uniform. It is also possible to cover. In the case where an organometallic compound is used as the charge control agent, it is also possible to introduce the compound by adding these compounds to the toner particles, and applying a shear and mixing and stirring.

  The amount of these charge control agents used is determined by the toner production method including the type of binder resin, the presence or absence of other additives, and the dispersion method, and is not uniquely limited. However, when added internally to the toner particles, it is preferably 0.1 parts by weight or more and 10.0 parts by weight or less, more preferably 0.1 parts by weight or more and 5.0 parts by weight or less with respect to 100 parts by weight of the binder resin. Used in a range. Further, when externally added to the toner particles, it is preferably 0.005 parts by mass or more and 1.000 parts by mass or less, more preferably 0.01 parts by mass or more and 0.30 parts by mass or less with respect to 100 parts by mass of the toner particles. .

  In the toner of the present invention, a release agent may be blended as necessary for improving the fixing property. As the release agent, all known release agents can be used. Specifically, petroleum wax such as paraffin wax, microcrystalline wax, petrolactam and derivatives thereof, montan wax and derivatives thereof, hydrocarbon wax and derivatives thereof by Fischer-Tropsch method, polyolefin wax and derivatives thereof typified by polyethylene, Natural waxes such as carnauba wax and candelilla wax and their derivatives, ester waxes and the like. As the ester wax, monofunctional ester wax, bifunctional ester wax, and other polyfunctional ester waxes such as tetrafunctional and hexafunctional can be used.

  The endothermic peak top temperature of the release agent used in the present invention is preferably 50 ° C. or higher and 90 ° C. or lower. When the endothermic peak top temperature is 50 ° C. or higher and 90 ° C. or lower, the toner is easily plasticized at the time of fixing, and the fixing property is improved. Moreover, even when left in a high-temperature and high-humidity environment, wax bleeding and the like are unlikely to occur.

  When a release agent is used in the toner of the present invention, it is preferable to use 2 to 30 parts by weight of the release agent with respect to 100 parts by weight of the binder resin. The content of 2 parts by mass or more and 30 parts by mass or less is preferable because the fixability is improved and the storage stability of the toner is easily improved.

  The toner of the present invention contains a magnetic material, and the amount of the magnetic material is preferably 20 parts by mass or more and 150 parts by mass or less with respect to 100 parts by mass of the binder resin. By adjusting the addition amount of the magnetic material to 20 parts by mass or more and 150 parts by mass or less, the coloring power is good, the fog is small, and good fixability can be obtained.

  Note that the content of the magnetic substance in the toner can be measured using a thermal analyzer, TGA7, manufactured by PerkinElmer. In the measurement method, the toner is heated from room temperature to 900 ° C. at a temperature rising rate of 25 ° C./min in a nitrogen atmosphere, and the weight loss from 100 ° C. to 750 ° C. is defined as the binder resin amount, and the remaining weight is approximated. The amount of magnetic material.

  The magnetic material used in the toner of the present invention is mainly composed of triiron tetroxide or γ-iron oxide, and may contain elements such as phosphorus, cobalt, nickel, copper, magnesium, manganese, and aluminum.

  Examples of the shape of the magnetic material used in the toner of the present invention include polyhedron, octahedron, hexahedron, sphere, needle shape, scale shape, etc., but those having little anisotropy such as polyhedron, octahedron, hexahedron, and sphere. Is preferable for increasing the image density.

  The magnetic material used in the toner of the present invention preferably has a volume average particle diameter (D3) of 0.10 μm or more and 0.40 μm or less. When the volume average particle diameter (D3) of the magnetic material is 0.10 μm or more and 0.40 μm or less, it is preferable because sufficient coloring power can be obtained and the dispersibility of the magnetic material can be improved and fogging can be reduced.

  In addition, the volume average particle diameter (D3) of a magnetic body can be measured using a transmission electron microscope. Specifically, after sufficiently dispersing the toner particles to be observed in the epoxy resin, a cured product obtained by curing in an atmosphere at a temperature of 40 ° C. for 2 days is obtained. The obtained cured product is used as a flaky sample by a microtome, and the particle diameters of 100 magnetic bodies in the field of view are measured with a transmission electron microscope (TEM) with a photograph with a magnification of 10,000 to 40,000 times. Then, the volume average particle diameter (D3) is calculated based on the equivalent diameter of a circle equal to the projected area of the magnetic material. It is also possible to measure the particle size with an image analyzer.

  The magnetic material used in the toner of the present invention can be produced, for example, by the following method. An aqueous solution containing ferrous hydroxide is prepared by adding an alkali such as sodium hydroxide in an amount equivalent to or greater than the iron component to the ferrous salt aqueous solution. Air was blown in while maintaining the pH of the prepared aqueous solution at 7.0 or higher, and ferrous hydroxide was oxidized while heating the aqueous solution to 70 ° C. or higher, and seed crystals serving as the core of the magnetic iron oxide particles were formed. First generate.

  Next, an aqueous solution containing about 1 equivalent of ferrous sulfate is added to the slurry-like liquid containing seed crystals based on the amount of alkali added previously. The pH of the liquid is maintained at 5.0 or higher and 10.0 or lower, and the reaction of ferrous hydroxide proceeds while blowing air, and magnetic iron oxide particles are grown with the seed crystal as a core. At this time, it is possible to control the shape and magnetic characteristics of the magnetic material by selecting an arbitrary pH, reaction temperature, and stirring conditions. As the oxidation reaction proceeds, the pH of the liquid shifts to the acidic side, but the pH of the liquid is preferably not less than 5.0. A magnetic material can be obtained by filtering, washing, and drying the magnetic material thus obtained by a conventional method.

  In the present invention, when a toner is produced by a polymerization method, it is very preferable to subject the surface of the magnetic material to a hydrophobic treatment. When the hydrophobizing treatment is performed by a dry method, the hydrophobizing treatment is performed on the washed, filtered and dried magnetic material using a coupling agent. When the hydrophobization treatment is performed in a wet manner, after the oxidation reaction is completed, the dried material is redispersed, or after the oxidation reaction is completed, the iron oxide body obtained by washing and filtering is not dried and another aqueous medium is used. It is redispersed in and hydrophobized. Specifically, the hydrophobization treatment is performed by adding a coupling agent while sufficiently stirring the re-dispersed liquid to increase the temperature after hydrolysis, or adjusting the pH of the dispersion to an alkaline region after hydrolysis. Among these, from the viewpoint of carrying out a uniform hydrophobization treatment, it is preferable to carry out the hydrophobization treatment after completion of the oxidation reaction, by reslurry as it is without drying after filtration and washing.

  To hydrophobize a magnetic material, that is, in order to treat the magnetic material with a coupling agent in an aqueous medium, first, sufficiently disperse the magnetic substance in the aqueous medium so as to have a primary particle size, and do not settle or aggregate. Stir with a stirring blade or the like. Next, an arbitrary amount of coupling agent is added to the above dispersion, and the coupling agent is hydrophobized while hydrolyzing, but at this time it is sufficient to avoid aggregation while using a device such as a pin mill or a line mill while stirring. It is more preferable to perform the hydrophobizing treatment while dispersing.

Here, the aqueous medium is a medium containing water as a main component. Specifically, water itself, water added with a small amount of a surfactant in water, obtained by adding a pH adjustment agent in water include those prepared by adding an organic solvent in water. As the surfactant, nonionic surfactants such as polyvinyl alcohol are preferable. The addition amount of the surfactant is preferably 0.1% by mass or more and 5.0% by mass or less with respect to 100 parts by mass of water. The pH adjustment agents include inorganic acids such as hydrochloric acid. Examples of the organic solvent include alcohols.

Examples of the silane compound that can be used for the surface treatment of magnetic iron oxide include those represented by the general formula (3).
R _m SiY _n (3)
[Wherein, R represents an alkoxy group, m represents an integer of 1 to 3, Y represents a functional group such as an alkyl group, a vinyl group, an epoxy group, or a (meth) acryl group, and n represents 1 to 3] Indicates an integer. However, m + n = 4. ]

  Examples of the silane compound represented by the general formula (3) include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (β-methoxyethoxy) silane, β- (3,4 epoxy cyclohexyl) ethyltrimethoxysilane, γ- Glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, γ-aminopropyltriethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, vinyltri Acetoxysilane, methyltrimethoxysilane, dimethyldimethoxysilane, phenyltrimethoxysilane, diphenyldimethoxysilane, methyltriethoxysilane, dimethyldiethoxysilane, phenyltriethoxysilane, diphenyldiet Sisilane, n-butyltrimethoxysilane, isobutyltrimethoxysilane, trimethylmethoxysilane, n-hexyltrimethoxysilane, n-octyltrimethoxysilane, n-octyltriethoxysilane, n-decyltrimethoxysilane, hydroxypropyltrimethoxy Examples thereof include silane, n-hexadecyltrimethoxysilane, and n-octadecyltrimethoxysilane.

Among these, from the viewpoint of imparting high hydrophobicity to magnetic iron oxide, it is preferable to use a silane compound represented by the following general formula (4).
_{C p H 2p + 1 -Si- (} OC q H 2q + 1) 3 (4)
[Wherein, p represents an integer of 2 to 20, and q represents an integer of 1 to 3. ]

  When p in the above formula is smaller than 2, it is difficult to sufficiently impart hydrophobicity to the magnetic iron oxide, and when p is larger than 20, the hydrophobicity is sufficient, but the coalescence of the magnetic iron oxides is It is not preferable because it increases. Furthermore, when q is larger than 3, the reactivity of the silane compound is lowered, and the hydrophobicity is not sufficiently performed. Therefore, a silane compound in which p represents an integer of 2 to 20 (more preferably, an integer of 3 to 15) and q represents an integer of 1 to 3 (more preferably, an integer of 1 or 2) is used. It is preferable to do.

  When the silane compound is used, it can be treated alone or in combination of a plurality of types. When using several types together, you may process separately with each silane compound, and may process simultaneously.

  The amount of the silane compound to be used is preferably 0.5 parts by mass or more and 5.0 parts by mass or less with respect to 100 parts by mass of the magnetic iron oxide, and the treatment agent depending on the surface area of the magnetic iron oxide, the reactivity of the silane compound, etc. It is important to adjust the amount.

  The toner of the present invention can be produced by any known method. First, in the case of producing by a pulverization method, for example, components necessary as a toner such as a binder resin, a magnetic material, and a release agent and other additives are sufficiently mixed by a mixer such as a Henschel mixer or a ball mill. Thereafter, the toner material is dispersed or dissolved by using a heat kneader such as a heating roll, a kneader, or an extruder to disperse or dissolve the toner material, and after cooling and solidification, pulverization, and surface treatment as necessary to obtain toner particles. be able to. Either the classification or the surface treatment may be performed first. In the classification step, it is preferable to use a multi-division classifier in terms of production efficiency.

  The pulverization step can be performed by a method using a known pulverizer such as a mechanical impact type or a jet type. Further, in order to obtain a toner having a preferable circularity of the present invention, it is preferable to further heat and pulverize, or to perform a process of applying a mechanical impact as an auxiliary. Further, a hot water bath method in which finely pulverized (classified as necessary) toner particles are dispersed in hot water, a method of passing in a hot air stream, or the like may be used.

  Examples of means for applying a mechanical impact force include a method using a mechanical impact pulverizer such as a kryptron system manufactured by Kawasaki Heavy Industries, Ltd. or a turbo mill manufactured by Turbo Industry. Further, there is a method in which a mechanical impact force is applied to the toner by a force such as a compressive force or a frictional force, as in a device such as a mechano-fusion system manufactured by Hosokawa Micron Corporation or a hybridization system manufactured by Nara Machinery Co., Ltd.

  The toner of the present invention can be produced by a pulverization method as described above, but the toner particles obtained by this pulverization method are generally indefinite. For this reason, it is difficult to obtain uniform chargeability, and the density is likely to decrease when left after endurance.

  Therefore, the toner particles of the present invention are preferably produced in an aqueous medium such as a dispersion polymerization method, an association aggregation method, a dissolution suspension method, a suspension polymerization method, and the suspension polymerization method is more preferable.

  In the suspension polymerization method, a polymerizable monomer and a magnetic substance (further, if necessary, a polymerization initiator, a crosslinking agent, a charge control agent, and other additives) are uniformly dissolved or dispersed to form a polymerizable monomer. A composition is obtained. Thereafter, the polymerizable monomer composition is dispersed in a continuous layer (for example, an aqueous phase) containing a dispersion stabilizer by using a suitable stirrer, and a polymerization reaction is simultaneously performed to obtain a toner having a desired particle size. To get. The toner obtained by this suspension polymerization method (hereinafter also referred to as “polymerized toner”) is preferable because the shape of individual toner particles is almost spherical, and the charge amount distribution is relatively uniform.

  In the production of the polymerized toner according to the present invention, examples of the polymerizable monomer constituting the polymerizable monomer composition include the following.

  Examples of the polymerizable monomer include styrene monomers such as styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, p-methoxystyrene, p-ethylstyrene, methyl acrylate, ethyl acrylate, Acrylate esters such as n-butyl acrylate, isobutyl acrylate, n-propyl acrylate, n-octyl acrylate, dodecyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, 2-chloroethyl acrylate, and phenyl acrylate , Methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, phenyl methacrylate, Methacrylic acid dimethyl aminoethyl, methacrylic acid esters such as diethylaminoethyl methacrylate and other acrylonitrile, methacrylonitrile, and the like monomers acrylamide. These monomers can be used alone or in combination. Among the above-mentioned monomers, styrene or a styrene derivative is preferably used alone or mixed with other monomers from the viewpoint of developing characteristics and durability of the toner.

  The polymerization initiator used in the production of the toner according to the present invention by polymerization is preferably one having a half-life of 0.5 hours or more and 30.0 hours or less during the polymerization reaction. Moreover, it is preferable that the addition amount of a polymerization initiator is 0.5 to 20.0 mass parts with respect to 100 mass parts of polymerizable monomers.

  Specific examples of the polymerization initiator include 2,2′-azobis- (2,4-dimethylvaleronitrile), 2,2′-azobisisobutyronitrile, 1,1′-azobis (cyclohexane-1- Carbonitrile), 2,2′-azobis-4-methoxy-2,4-dimethylvaleronitrile, azo or isoazo polymerization initiators such as azobisisobutyronitrile, benzoyl peroxide, methyl ethyl ketone peroxide, diisopropyl peroxide Peroxide polymerization initiators such as oxycarbonate, cumene hydroperoxide, 2,4-dichlorobenzoyl peroxide, lauroyl peroxide, t-butylperoxy 2-ethylhexanoate, t-butylperoxypivalate, etc. Can be mentioned.

  When the toner of the present invention is produced by a polymerization method, a crosslinking agent may be added. A preferable addition amount is 0.01 parts by mass or more and 10.00 parts by mass or less with respect to 100 parts by mass of the polymerizable monomer. It is.

  Here, as the crosslinking agent, compounds having two or more polymerizable double bonds are mainly used. For example, aromatic divinyl compounds such as divinylbenzene and divinylnaphthalene, such as ethylene glycol diacrylate and ethylene glycol diacrylate. Carboxylic acid ester having two double bonds, such as methacrylate, 1,3-butanediol dimethacrylate, divinyl compounds such as divinylaniline, divinyl ether, divinyl sulfide, divinyl sulfone, and three or more vinyl groups A compound is used alone or as a mixture of two or more.

  In the method for producing the toner of the present invention by a polymerization method, generally, the above-described toner composition or the like is added as appropriate, and the polymerizable single particle is uniformly dissolved or dispersed by a disperser such as a homogenizer, a ball mill, or an ultrasonic disperser. The meter composition is suspended in an aqueous medium containing a dispersion stabilizer. At this time, the particle size of the obtained toner particles becomes sharper by using a disperser such as a high-speed stirrer or an ultrasonic disperser to obtain a desired toner particle size all at once. The polymerization initiator may be added at the same time as other additives are added to the polymerizable monomer, or may be mixed immediately before being suspended in the aqueous medium. Also, a polymerization initiator dissolved in a polymerizable monomer or solvent can be added immediately after granulation and before starting the polymerization reaction.

  After granulation, stirring may be performed using a normal stirrer to such an extent that the particle state is maintained and particle floating and sedimentation are prevented.

  When the toner of the present invention is produced, known surfactants, organic dispersants and inorganic dispersants can be used as the dispersion stabilizer. In particular, inorganic dispersants are less likely to produce harmful ultrafine powders, and because of their steric hindrance, dispersion stability is obtained, so even if the reaction temperature is changed, stability is not easily lost, and washing is easy and does not adversely affect the toner. Therefore, it can be preferably used. Examples of such inorganic dispersants include tricalcium phosphate, magnesium phosphate, aluminum phosphate, zinc phosphate, phosphate polyvalent metal salts such as hydroxyapatite, carbonates such as calcium carbonate and magnesium carbonate, calcium metasuccinate, calcium sulfate, Examples thereof include inorganic salts such as barium sulfate and inorganic compounds such as calcium hydroxide, magnesium hydroxide, and aluminum hydroxide.

  These inorganic dispersants are preferably used in an amount of 0.20 parts by mass or more and 20.00 parts by mass or less with respect to 100 parts by mass of the polymerizable monomer. Moreover, the said dispersion stabilizer may be used independently and may use multiple types together. Furthermore, you may use together 0.0001 mass part or more and 0.1000 mass part or less surfactant with respect to 100 mass parts of polymerizable monomers.

  In the step of polymerizing the polymerizable monomer, the polymerization temperature is set to 40 ° C or higher, and generally 50 ° C to 90 ° C.

  After the polymerization of the polymerizable monomer is completed, the obtained polymer particles are filtered, washed and dried by a known method to obtain toner particles. The toner of the present invention can be obtained by mixing the toner particles with inorganic fine powder as will be described later as necessary and adhering them to the surface of the toner particles. It is also possible to insert a classification step in the manufacturing process (before mixing the inorganic fine powder) to cut coarse powder and fine powder contained in the toner particles.

  The toner of the present invention preferably has an inorganic fine powder, and the inorganic fine powder preferably has a number average primary particle size (D1) of 4 nm to 80 nm, more preferably 6 nm to 40 nm.

  When the number average primary particle size (D1) of the inorganic fine powder is 4 nm or more and 80 nm or less, the fluidity of the toner is excellent, and uniform chargeability can be obtained, and a uniform image can be obtained even in long-term use. I can get it.

  In the present invention, the number average primary particle size (D1) of the inorganic fine powder is measured using a photograph of the toner magnified by a scanning electron microscope.

  Silica, titanium oxide, alumina, etc. can be used as the inorganic fine powder used in the present invention. As the fine silica powder, for example, both a so-called dry method produced by vapor phase oxidation of silicon halide or dry silica called fumed silica, and so-called wet silica produced from water glass or the like can be used. is there.

  In the present invention, the addition amount of the inorganic fine powder is preferably 0.1 parts by mass or more and 5.0 parts by mass or less with respect to 100 parts by mass of the toner particles. The addition amount of the inorganic fine powder is preferably in the above range since the toner can be given good fluidity and the fixing property is not hindered.

  The content of the inorganic fine powder can be quantified using a calibration curve prepared from a standard sample using fluorescent X-ray analysis.

  Next, an example of an image forming apparatus that can suitably use the toner of the present invention will be specifically described with reference to FIG. In FIG. 1, reference numeral 100 denotes an electrostatic latent image carrier (hereinafter also referred to as a photoconductor), which includes a charging roller 117, a developing device 140 having a toner carrier 102, a transfer charging roller 114, a cleaner 116, and a register roller. 124 etc. are provided. The electrostatic latent image carrier 100 is charged to, for example, −600 V by the charging roller 117 (applied voltages are, for example, an AC voltage of 1.85 kVpp and a DC voltage of −620 Vdc). Then, exposure is performed by irradiating the electrostatic latent image carrier 100 with the laser beam 123 by the laser generator 121, and an electrostatic latent image corresponding to the target image is formed. The electrostatic latent image on the electrostatic latent image carrier 100 is developed with a one-component toner by the developing device 140 to obtain a toner image, and the toner image is brought into contact with the electrostatic latent image carrier via the transfer material P. The image is transferred onto the transfer material by the transfer roller 114. The transfer material P on which the toner image is placed is conveyed to the fixing device 126 by the conveying belt 125 or the like and fixed on the transfer material. In addition, the toner remaining on the electrostatic latent image carrier is partially cleaned by the cleaner 116.

  Next, a method for measuring each physical property related to the toner of the present invention will be described.

(1) Average Particle Size of Toner The weight average particle size (D4) of the toner of the present invention is a precision particle size distribution measuring device “Coulter Counter Multisizer 3” (registered trademark) using a pore electrical resistance method equipped with a 100 μm aperture tube. Using Beckman Coulter Multisizer 3 Version 3.51 (manufactured by Beckman Coulter, Inc.) and the attached dedicated software “Beckman Coulter Multisizer 3 Version 3.51” (manufactured by Beckman Coulter, Inc.) Measurements were taken with 55,000 channels, and the measurement data was analyzed and calculated.
As the electrolytic aqueous solution used for the measurement, special grade sodium chloride is dissolved in ion-exchanged water so as to have a concentration of about 1% by mass, for example, “ISOTON II” (manufactured by Beckman Coulter, Inc.) can be used.

  Prior to measurement and analysis, dedicated software was set up as follows.

  In the “Standard Measurement Method (SOM) Change Screen” of the dedicated software, set the total count in the control mode to 50000 particles, set the number of measurements once, and set the Kd value to “standard particles 10.0 μm” (Beckman Coulter, Inc.) Set the value obtained using The threshold and noise level are automatically set by pressing the threshold / noise level measurement button. Also, the current is set to 1600 μA, the gain is set to 2, the electrolyte is set to ISOTON II, and the aperture tube flash after measurement is checked.

In the “pulse to particle size conversion setting screen” of the dedicated software, the bin interval is set to logarithmic particle size, the particle size bin is set to 256 particle size bin, and the particle size range is set to 2 μm to 60 μm.
The specific measurement method is as follows.
1-1) About 200 ml of the electrolytic solution is put in a glass 250 ml round bottom beaker exclusively for Multisizer 3, set on a sample stand, and the stirrer rod is stirred counterclockwise at 24 rpm. Then, dirt and bubbles in the aperture tube are removed by the “aperture flush” function of the analysis software.
1-2) About 30 ml of the electrolytic aqueous solution is put in a glass 100 ml flat bottom beaker, and “Contaminone N” (nonionic surfactant, anionic surfactant, organic builder pH 7 precision is used as a dispersant therein. About 0.3 ml of a dilute solution obtained by diluting a 10% by weight aqueous solution of a neutral detergent for measuring device washing (manufactured by Wako Pure Chemical Industries, Ltd.) 3 times by weight with ion-exchanged water is added.
1-3) Two oscillators with an oscillation frequency of 50 kHz are incorporated in a state where the phase is shifted by 180 degrees, and placed in a water tank of an ultrasonic disperser “Ultrasonic Dissipation System Tetora 150” (manufactured by Nikka Ki Bios) with an electrical output of 120 W. A predetermined amount of ion-exchanged water is put, and about 2 ml of the above-mentioned Contaminone N is added to this water tank.
1-4) The beaker of 1-2) is set in the beaker fixing hole of the ultrasonic disperser, and the ultrasonic disperser is operated. And the height position of a beaker is adjusted so that the resonance state of the liquid level of the electrolyte solution in a beaker may become the maximum.
1-5) In a state where the electrolytic aqueous solution in the beaker of 1-4) is irradiated with ultrasonic waves, about 10 mg of toner is added to the electrolytic aqueous solution little by little and dispersed. Then, the ultrasonic dispersion process is continued for another 60 seconds. In the ultrasonic dispersion, the temperature of the water tank is appropriately adjusted so as to be 10 ° C. or higher and 40 ° C. or lower.
1-6) Into the round bottom beaker of (1) installed in a sample stand, the electrolyte solution of 1-5) in which toner is dispersed is dropped using a pipette so that the measured concentration is about 5%. adjust. The measurement is performed until the number of measured particles reaches 50,000.
1-7) Analyze the measurement data with the dedicated software attached to the device and calculate the weight average particle diameter (D4. Note that the analysis / volume statistics (when graph / volume% is set with the dedicated software) The “average diameter” on the (arithmetic average) screen is the weight average particle diameter (D4).

(2) Surface free energy The surface free energy of the magnetic toner surface and the surface of the toner carrier is measured using the following apparatus, and in accordance with the operation manual of the apparatus, the probe liquid (water, diiodomethane, ethylene glycol) whose surface free energy is known is known. Was measured under the following conditions.

Specifically, using a contact angle meter CA-X ROLL type manufactured by Kyowa Interface Science Co., Ltd., the contact angle θ of each of the probe liquids on the surfaces of the magnetic toner and the toner carrier is measured. The surface free energy was calculated using a theoretical formula.
(I) The detailed measurement conditions of the contact angle θ are as follows.
Measurement: Droplet method (perfect circle fitting)
Liquid volume: 1 μl
Droplet recognition: Automatic Image processing: Algorithm-Non-reflective Image mode: Frame Threshold level: Automatic

  Regarding the contact angle θ, each probe liquid was measured five times, and the average value of the five times was used as the contact angle θ of the probe liquid. FAMAS (manufactured by Kyowa Interface Science Co., Ltd.) was used for data analysis.

The toner used was a press molding machine MAEKAWA Testing Machine (manufactured by MFG Co, LTD), pellets were prepared under the following conditions, and surface free energy was measured under the above conditions.
Aluminum ring: 30mm in diameter
Toner: 4.1g
Press pressure: 200kgf
Press time: 3 minutes

(3) Measurement of median diameter and span value B of fatty acid metal salt The volume-based median diameter of the fatty acid metal salt used in the present invention is measured according to JIS Z8825-1 (2001). Specifically, it is as follows.

  As a measuring device, a laser diffraction / scattering particle size distribution measuring device “LA-920” (manufactured by Horiba, Ltd.) is used. The dedicated software “HORIBA LA-920 for Windows (registered trademark) WET (LA-920) Ver. 2.02” attached to LA-920 is used for setting measurement conditions and analyzing measurement data. As the measurement solvent, ion-exchanged water from which impure solids are removed in advance is used.

The measurement procedure is as follows.
(1) A batch type cell holder is attached to LA-920.
(2) A predetermined amount of ion-exchanged water is put into a batch type cell, and the batch type cell is set in a batch type cell holder.
(3) The inside of the batch cell is stirred using a dedicated stirrer chip.
(4) Press the “refractive index” button on the “display condition setting” screen and select the file “110A000I” (relative refractive index 1.10).
(5) In the “display condition setting” screen, the particle diameter reference is set as the volume reference.
(6) After performing warm-up operation for 1 hour or more, optical axis adjustment, optical axis fine adjustment, and blank measurement are performed.
(7) Put about 60 ml of ion-exchanged water in a glass 100 ml flat bottom beaker. Among them, as a dispersant, “Contaminone N” (a nonionic surfactant, an anionic surfactant, a 10% by weight aqueous solution of a neutral detergent for washing a pH 7 precision measuring instrument comprising an organic builder, Wako Pure Chemical Industries, Ltd. About 0.3 ml of a diluted solution obtained by diluting the product (manufactured) with ion exchange water about 3 times by mass is added.
(8) Two oscillators with an oscillation frequency of 50 kHz are incorporated with the phase shifted by 180 degrees, and an ultrasonic disperser “Ultrasonic Dissipation System Tetora 150” (manufactured by Nikki Bios Co., Ltd.) having an electrical output of 120 W is prepared. About 3.3 l of ion-exchanged water is placed in the water tank of the ultrasonic disperser, and about 2 ml of Contaminone N is added to the water tank.
(9) The beaker of (7) is set in the beaker fixing hole of the ultrasonic disperser, and the ultrasonic disperser is operated. And the height position of a beaker is adjusted so that the resonance state of the liquid level of the aqueous solution in a beaker may become the maximum.
(10) In a state where the aqueous solution in the beaker of (9) is irradiated with ultrasonic waves, about 1 mg of a fatty acid metal salt is added to the aqueous solution in the beaker little by little and dispersed. Then, the ultrasonic dispersion process is continued for another 60 seconds. In this case, the fatty acid metal salt may solidify and float on the liquid surface. In that case, ultrasonic dispersion is performed for 60 seconds after the mass is submerged by shaking the beaker. Moreover, in ultrasonic dispersion, it adjusts suitably so that the water temperature of a water tank may become 10 to 40 degreeC.
(11) The aqueous solution in which the fatty acid metal salt prepared in the above (10) is dispersed is immediately added little by little to a batch type cell, taking care not to enter bubbles, and the transmittance of the tungsten lamp is 90% to 95%. Adjust so that Then, the particle size distribution is measured. Based on the obtained volume-based particle size distribution data, 5% integrated diameter, 50% integrated diameter, and 95% integrated diameter are calculated. The obtained values are D5, D50, and D95, and the span value B is obtained from these values.

(4) Glass transition point (Tg)
The glass transition point (Tg) of the polyester resin used for the toner and the shell layer is determined by DSC according to ASTM D 3418-99.

  The peak top of the endothermic peak is measured according to ASTM D 3417-99. For these measurements, for example, DSC-7 manufactured by PerkinElmer, DSC2920 manufactured by TA Instruments, and Q1000 manufactured by TA Instruments can be used. The temperature correction of the device detection unit uses the melting points of indium and zinc, and the correction of heat uses the heat of fusion of indium. An aluminum pan is used as a measurement sample, and an empty pan is set for control and measured.

(5) Compression rate In this invention, a compression rate is a value obtained by a following formula.
Compression rate = {1− (apparent density / tap density)} × 100

  The apparent density and tap density of the present invention are measured by the following method using a powder tester (manufactured by Hosokawa Micron).

A cylindrical container having a diameter of 5.03 cm, a height of 5.03 cm, and a volume of 100 cm ³ is uniformly fed from above through a sieve having a mesh opening of 608 μm (24 mesh) for 30 seconds, and the apparent density ( g / cm ³ ).

After measuring the apparent density, a cylindrical cap is put on, powder is added to this upper edge, and tapping with a tap height of 1.8 cm is performed 180 times. After completion, the cap is removed, the powder is ground on the upper surface of the container and weighed, and the density in this state is defined as the tap density (g / cm ³ ).

(6) Release rate of fatty acid metal salt The release rate of the fatty acid metal salt in the toner according to the present invention includes KM Shaker (manufactured by Iwaki Sangyo Co., Ltd.), X-ray fluorescence analyzer Axios (manufactured by PANalytical), measurement condition setting and measurement data. The liberation rate of the fatty acid metal salt is determined from the intensity difference of the fluorescent X-rays using the attached dedicated software “SuperQ ver. 4.0F” (manufactured by PANalytical) for analysis.

Specific measurement methods are as follows.
(1) About 1 g of toner is placed on a PVC ring having a ring diameter of 22 mm × 16 mm × 5 mm, and compressed with 100 kgf by a press machine to prepare a sample. The obtained sample is measured with a fluorescent X-ray analyzer (Axios) to obtain the net strength derived from the metal element of the fatty acid metal salt contained in the toner.
(2) The toner particles are also measured with a fluorescent X-ray analyzer (Axios) in the same manner as in (1), and the net intensity derived only from the toner particles is obtained for the metal element contained in the fatty acid metal salt.
(3) Precisely evaluate 1 g of toner and add 16 g of methanol to a 30 cc vial. The toner is put into the vial, left to stand for 30 seconds, shaken under the following conditions, and the toner is separated by magnetic force.

[Shaking device / conditions]
Device: KM Shaker (manufactured by Iwaki Sangyo Co., Ltd.)
model: V. SX
Shaking conditions: Speed is set to 50 and shaken for 10 seconds. The separated toner is dried overnight in a vacuum dryer, and about 1 g of the obtained sample is placed on the same vinyl ring as in (1), and then pressed. Compress with 100kgf to make a sample. The obtained sample is measured with a fluorescent X-ray analyzer (Axios), and the net intensity derived from the fatty acid metal salt contained in the sample after shaking in methanol is obtained.

  Note that Rh is used as the anode of the X-ray tube, the measurement atmosphere is vacuum, the measurement diameter (collimator mask diameter) is 10 mm, and the measurement time is 300 seconds. Further, when measuring a light element, it is detected by a proportional counter (PC), and when measuring a heavy element, it is detected by a scintillation counter (SC).

The liberation rate of the fatty acid metal salt is determined from the following formula by measuring the Kα-ray net intensity (KCPS) of the metal element of the fatty acid metal salt before and after shaking with methanol.
Fatty acid metal salt liberation rate (%) = {(BT)-(AT)} / (BT) × 100
A: Net strength of metal element of fatty acid metal salt in toner after methanol shaking B: Net strength of metal element of fatty acid metal salt in toner before methanol shaking T: Net strength of toner particles

  Hereinafter, the present invention will be described more specifically with reference to production examples and examples, but these do not limit the present invention in any way. In addition, all the parts in the following mixing | blending show a part.

<Manufacture of magnetic body 1>
During an aqueous ferrous sulfate solution, 1.10 eq of sodium hydroxide solution from 1.00 relative to iron element, the amount of P ₂ O ₅ to an iron element to be 0.15% by mass in terms of phosphorus, the iron element On the other hand, SiO ₂ in an amount of 0.50% by mass in terms of silicon element was mixed to prepare an aqueous solution containing ferrous hydroxide. The pH of the aqueous solution was 8.0, and an oxidation reaction was performed at 85 ° C. while blowing air to prepare a slurry liquid having seed crystals.

  Subsequently, after adding ferrous sulfate aqueous solution so that it may become 0.90 to 1.20 equivalent with respect to the original alkali amount (sodium component of caustic soda) to this slurry liquid, the slurry liquid is maintained at pH 7.6, The oxidation reaction was promoted while blowing air to obtain a slurry liquid containing magnetic iron oxide. After filtration and washing, the water-containing slurry was once taken out. At this time, a small amount of water-containing sample was collected and the water content was measured. Next, this water-containing sample is put into another aqueous medium without being dried, stirred and redispersed with a pin mill while circulating the slurry, and the pH of the redispersed liquid is adjusted to about 4.8. Then, 1.6 parts of n-hexyltrimethoxysilane coupling agent was added to 100 parts of magnetic iron oxide with stirring (the amount of magnetic iron oxide was calculated as a value obtained by subtracting the water content from the water-containing sample), and water was added. Decomposition was performed. Thereafter, the mixture was sufficiently stirred, and the dispersion was subjected to surface treatment at a pH of 8.6. The produced hydrophobic magnetic material is filtered with a filter press, washed with a large amount of water, dried at 100 ° C. for 15 minutes, and then at 90 ° C. for 30 minutes. 0.21 μm magnetic body 1 was obtained.

<Manufacture of magnetic body 2>
During an aqueous ferrous sulfate solution, 1.10 eq of sodium hydroxide solution from 1.00 relative to iron element, the amount of P ₂ O ₅ to an iron element to be 0.15% by mass in terms of phosphorus, the iron element On the other hand, SiO ₂ in an amount of 0.50% by mass in terms of silicon element was mixed to prepare an aqueous solution containing ferrous hydroxide. The pH of the aqueous solution was 8.0, and an oxidation reaction was performed at 85 ° C. while blowing air to prepare a slurry liquid having seed crystals. Subsequently, after adding ferrous sulfate aqueous solution so that it may become 0.90 to 1.20 equivalent with respect to the original alkali amount (sodium component of caustic soda) to this slurry liquid, the slurry liquid is maintained at pH 7.6, The oxidation reaction was promoted while blowing air to obtain a slurry liquid containing magnetic iron oxide. After filtration, washing and drying, the obtained particles were crushed to obtain a magnetic body 2 having a volume average particle size of 0.21 μm.

<Synthesis of polyester resin 1>
In a reaction vessel equipped with a cooling tube, a stirrer, and a nitrogen introduction tube, monomer components other than trimellitic anhydride shown in Table 1 are added in the molar ratio shown in the table, the following components are added, and nitrogen is added at 230 ° C. It was made to react for 10 hours, distilling off the water produced | generated under air flow. At this time, as a catalyst, 0.25 parts of titanium-based catalyst (titanium dihydroxybis (triethanolaminate)) was added to 100 parts of the total amount of acid / alcohol monomers.

  Next, the reaction is carried out under a reduced pressure of 20 mmHg. When the acid value becomes 2 or less, it is cooled to 180 ° C., trimellitic anhydride is added, taken out after reaction for 2 hours under normal pressure sealing, cooled to room temperature, and then pulverized. To obtain a polyester resin. The obtained polyester resin 1 had Mp = 10500 and a glass transition point of 86 ° C.

<Synthesis of polyester resins 2 to 5>
Except having changed into the monomer composition as shown in Table 1, it carried out similarly to the synthesis | combination of the polyester resin 1, and obtained polyester resin 2 thru | or 5. Table 1 shows the glass transition point and Mp of the obtained polyester resin.

  In the above table, BPA-PO (2): bisphenol A propylene oxide 2 mol adduct, BPA-PO (3): bisphenol A propylene oxide 3 mol adduct, TPA: terephthalic acid, TMA: trimellitic anhydride , Respectively.

<Production of fatty acid metal salt 1>
A container with a stirrer was prepared, and the stirrer was rotated at 350 rpm. 500 parts of 0.5 mass% sodium stearate aqueous solution was put into this receiving container, and the liquid temperature was adjusted to 85 ° C. Next, 525 parts of 0.2 mass% zinc sulfate aqueous solution was dripped at this receptacle over 15 minutes. After the completion of charging the whole amount, the reaction was terminated by aging for 10 minutes at the temperature during the reaction.

Next, the fatty acid metal salt slurry thus obtained was washed by filtration. The obtained washed fatty acid metal salt cake was roughly crushed and then dried at 105 ° C. using a continuous instantaneous air dryer. Then, after pulverizing with a nano grinding mill [NJ-300] (manufactured by Sanrex) under conditions of an air volume of 6.0 m ³ / min and a processing speed of 80 kg / h, reslurry and fine particles using a wet centrifugal classifier The coarse particles were removed. Then, it dried at 80 degreeC using the continuous instantaneous airflow dryer, and obtained the fatty acid metal salt 1. The obtained fatty acid metal salt 1 had a volume-based median diameter (D50) of 0.45 μm and a span value B of 0.92. The physical properties of the fatty acid metal salt 1 are shown in Table 2.

<Production of fatty acid metal salt 2>
In the production of the fatty acid metal salt 1, the 0.2 mass% zinc sulfate aqueous solution was changed to a 0.3 mass% calcium chloride aqueous solution. Other steps were carried out in the same manner as in the production of the fatty acid metal salt 1 to obtain the fatty acid metal salt 2. The resulting fatty acid metal salt 2 had a volume-based median diameter (D50) of 0.50 μm and a span value B of 1.22. Table 2 shows the physical properties of the fatty acid metal salt 2.

<Production of fatty acid metal salt 3>
In the production of the fatty acid metal salt 1, the 0.5 mass% sodium stearate aqueous solution was changed to a 0.25 mass% sodium stearate aqueous solution, and the 0.2 mass% zinc sulfate aqueous solution was changed to a 0.15 mass% zinc sulfate aqueous solution. Other steps were carried out in the same manner as in the production of fatty acid metal salt 1 to obtain fatty acid metal salt 3. The resulting fatty acid metal salt 3 had a volume-based median diameter (D50) of 0.30 μm and a span value B of 0.83. The physical properties of the fatty acid metal salt 3 are shown in Table 2.

<Production of fatty acid metal salt 4>
In the production of fatty acid metal salt 1, 0.5% by mass sodium stearate aqueous solution was changed to 0.7% by mass sodium stearate, and 0.2% by mass zinc sulfate aqueous solution was changed to 0.4% by mass zinc sulfate aqueous solution. . The pulverization conditions were an air volume of 4.0 m ³ / min and a treatment speed of 40 kg / h. Other steps were carried out in the same manner as in the production of fatty acid metal salt 1 to obtain fatty acid metal salt 4. The obtained fatty acid metal salt 4 had a volume-based median diameter (D50) of 0.60 μm and a span value B of 1.12. The physical properties of the fatty acid metal salt 4 are shown in Table 2.

<Production of fatty acid metal salt 5>
In the production of fatty acid metal salt 1, 0.5% by mass sodium stearate aqueous solution was changed to 0.8% by mass sodium stearate, and 0.2% by mass zinc sulfate aqueous solution was changed to 0.4% by mass zinc sulfate aqueous solution. . The pulverization conditions were an air volume of 3.5 m ³ / min and a processing speed of 40 kg / h. Other steps were carried out in the same manner as in the production of fatty acid metal salt 1 to obtain fatty acid metal salt 5. The resulting fatty acid metal salt 5 had a volume-based median diameter (D50) of 0.65 μm and a span value B of 1.35. The physical properties of the fatty acid metal salt 5 are shown in Table 2.

<Production of fatty acid metal salt 6>
In the production of fatty acid metal salt 1, 0.5% by mass sodium stearate aqueous solution was changed to 0.8% by mass sodium stearate, and 0.2% by mass zinc sulfate aqueous solution was changed to 0.4% by mass zinc sulfate aqueous solution. . Further, the pulverization conditions were changed to an air volume of 3.5 m ³ / min and a processing speed of 40 kg / h, and after the pulverization, fine coarse powder was removed with a wind classifier. Other processes were the same as the production of fatty acid metal salt 1 to obtain fatty acid metal salt 6. The obtained fatty acid metal salt 6 had a volume-based median diameter (D50) of 0.65 μm and a span value B of 1.75. The physical properties of the fatty acid metal salt 5 are shown in Table 2.

<Production of fatty acid metal salt 7>
In the production of the fatty acid metal salt 6, the classification conditions of the wind classifier were changed, and fine coarse powder was removed. Other steps were carried out in the same manner as in the production of fatty acid metal salt 6 to obtain fatty acid metal salt 7. The volume-based median diameter (D50) of the obtained fatty acid metal salt 7 was 0.65 μm, and the span value B was 1.92. The physical properties of the fatty acid metal salt 7 are shown in Table 2.

<Production of fatty acid metal salt 8>
In the production of fatty acid metal salt 1, 0.5% by mass sodium stearate aqueous solution was changed to 1.0% by mass sodium stearate, and 0.2% by mass zinc sulfate aqueous solution was changed to 0.4% by mass zinc sulfate aqueous solution. . Further, the reaction was terminated by aging for 15 minutes. Further, the pulverization condition was changed to 4.0 m ³ / min. Other steps were carried out in the same manner as the production of fatty acid metal salt 1 to obtain fatty acid metal salt 8. The obtained fatty acid metal salt 8 had a volume-based median diameter (D50) of 0.72 μm and a span value B of 1.26. The physical properties of the fatty acid metal salt 8 are shown in Table 2.

<Production of fatty acid metal salt 9>
In the production of fatty acid metal salt 1, the 0.5 mass% sodium stearate aqueous solution was changed to a 0.3 mass% sodium stearate aqueous solution, and the 0.2 mass% zinc sulfate aqueous solution was changed to a 0.15 mass% zinc sulfate aqueous solution. Further, the pulverization condition was changed to an air volume of 10.0 m ³ / min, and the pulverization process was changed three times. Other steps were carried out in the same manner as in the production of fatty acid metal salt 1 to obtain fatty acid metal salt 9. The resulting fatty acid metal salt 9 had a median diameter (D50) based on volume of 0.15 μm and a span value B of 1.22. Table 2 shows the physical properties of the fatty acid metal salt 9.

<Production of fatty acid metal salt 10>
In the production of fatty acid metal salt 1, 0.5% by mass sodium stearate aqueous solution was changed to 0.05% by mass sodium stearate, and 0.2% by mass zinc sulfate aqueous solution was changed to 0.02% by mass zinc sulfate aqueous solution. did. Further, the pulverization condition was changed to an air volume of 10.0 m ³ / min, and the pulverization process was changed three times. Other processes were the same as the production of the fatty acid metal salt 1 to obtain the fatty acid metal salt 10. The resulting fatty acid metal salt 10 had a volume-based median diameter (D50) of 0.12 μm and a span value B of 1.25. Table 2 shows the physical properties of the fatty acid metal salt 10.

<Fatty acid metal salt 11>
Commercially available zinc stearate (MZ2 manufactured by NOF Corporation) is used as fatty acid metal salt 11. The median diameter (D50) on a volume basis was 1.29 μm, and the span value B was 1.61. Table 2 shows the physical properties of the fatty acid metal salt 11.

<Fatty acid metal salt 12>
Commercially available zinc stearate (SZ2000, manufactured by Sakai Chemical Industry Co., Ltd.) is designated as fatty acid metal salt 12. The median diameter (D50) on a volume basis was 5.30 μm, and the span value B was 1.84. The physical properties of the fatty acid metal salt 12 are shown in Table 2.

<Manufacture of toner 1>
450 parts of 0.1M Na ₃ PO ₄ aqueous solution is added to 720 parts of ion-exchanged water and heated to 60 ° C., and then 67.7 parts of 1.0M CaCl ₂ aqueous solution is added to contain a dispersion stabilizer. An aqueous medium was obtained.
・ Styrene 78.0 parts ・ N-butyl acrylate 22.0 parts ・ Divinylbenzene 0.6 parts ・ Monoazo dye iron complex (T-77: Hodogaya Chemical Co., Ltd.) 3.0 parts ・ Magnetic substance 1 90.0 parts -Polyester resin 1 5.0 parts The said prescription was uniformly disperse-mixed using the attritor (Mitsui Miike Kako Co., Ltd.), and the monomer composition was obtained. This monomer composition was heated to 60 ° C., and 15.0 parts of Fischer-Tropsch wax was added and mixed therein. After dissolution, 7.0 parts of dilauroyl peroxide was dissolved as a polymerization initiator.

The monomer composition was charged into the aqueous medium, and granulated by stirring at 12,000 rpm for 10 minutes in a TK homomixer (Special Machine Industries Co., Ltd.) in an N ₂ atmosphere at 60 ° C. Thereafter, the mixture was reacted at 74 ° C. for 6 hours while stirring with a paddle stirring blade.

  After completion of the reaction, the suspension was cooled, washed with hydrochloric acid, filtered and dried to obtain magnetic toner particles 1.

  100.00 parts of this magnetic toner particle 1, 1.00 parts of hydrophobic silica fine powder having a number average primary particle size of 12 nm, and 0.20 part of fatty acid metal salt 1 are added to a Henschel mixer (Mitsui Miike Chemical Co., Ltd.). It was thrown into. Then, the peripheral speed of the stirring blade was 40 m / sec, and stirring and mixing were performed for 4 minutes. Thereafter, stirring / mixing was stopped for 1 minute, and the stirring blade was rotated and mixed at a peripheral speed of 40 m / sec for 4 minutes to obtain magnetic toner 1 having a weight average particle diameter (D4) of 6.8 μm. When the obtained magnetic toner 1 was analyzed, it contained 100 parts of a binder resin. Table 3 shows the physical properties of the magnetic toner 1.

<Manufacture of toner 2>
A magnetic toner 2 was obtained in the same manner as in the production of the toner 1 except that the fatty acid metal salt 1 was changed to the fatty acid metal salt 2 in the production of the toner 1. Table 3 shows the physical properties of the magnetic toner 2.

<Manufacture of toner 3>
In the production of the toner 1, the magnetic toner 3 was obtained in the same manner as the production of the toner 1 except that the fatty acid metal salt 1 was changed to the fatty acid metal salt 3 and the addition amount was changed to 0.05 part. Table 3 shows the physical properties of the magnetic toner 3.

<Manufacture of toner 4>
In the production of the toner 1, the polyester resin 1 was changed to the polyester resin 2. Further, the magnetic toner 4 was obtained in the same manner as in the production of the toner 1 except that the fatty acid metal salt 1 was changed to the fatty acid metal salt 4 and the addition amount was changed to 0.40 part. Table 3 shows the physical properties of the magnetic toner 4.

<Manufacture of toner 5>
In the production of the toner 1, the polyester resin 1 was changed to the polyester resin 2. Further, a magnetic toner 5 was obtained in the same manner as in the production of the toner 1 except that the fatty acid metal salt 1 was changed to the fatty acid metal salt 4 and the addition amount was changed to 0.50 part. Table 3 shows the physical properties of the magnetic toner 5.

<Manufacture of toner 6>
A magnetic toner 6 was obtained in the same manner as in the production of the toner 5 except that the polyester resin 2 was changed to the polyester resin 3 in the production of the toner 5. Table 3 shows the physical properties of the magnetic toner 6.

<Manufacture of toner 7>
A magnetic toner 7 was obtained in the same manner as in the production of the toner 5 except that the polyester resin 2 was changed to the polyester resin 4 in the production of the toner 5. Table 3 shows the physical properties of the magnetic toner 7.

<Manufacture of toner 8>
A magnetic toner 8 was obtained in the same manner as in the production of the toner 5 except that the polyester resin 2 was changed to the polyester resin 5 in the production of the toner 5. Table 3 shows the physical properties of the magnetic toner 8.

<Manufacture of toner 9>
Magnetic toner similar to the production of toner 5 except that polyester resin 2 is changed to styrene-acrylic resin (peak molecular weight = 10000, glass transition point: 74 ° C., acid value = 10 mg / KOH) in the production of toner 5. 9 was obtained. Table 3 shows the physical properties of the magnetic toner 9.

<Manufacture of Toner 10>
In the production of the toner 1, the magnetic toner 10 was obtained in the same manner as in the production of the toner 1 except that the fatty acid metal salt 1 was changed to the fatty acid metal salt 9 and the addition amount was changed to 0.05 part. Table 3 shows the physical properties of the magnetic toner 10.

<Manufacture of toner 11>
A magnetic toner 11 was obtained in the same manner as in the production of the toner 5 except that the fatty acid metal salt 4 was changed to the fatty acid metal salt 5 in the production of the toner 5. Table 3 shows the physical properties of the magnetic toner 11.

<Manufacture of toner 12>
A magnetic toner 12 was obtained in the same manner as in the production of the toner 5 except that the fatty acid metal salt 4 was changed to the fatty acid metal salt 6 in the production of the toner 5. Table 3 shows the physical properties of the magnetic toner 12.

<Manufacture of toner 13>
A magnetic toner 13 was obtained in the same manner as in the production of the toner 5 except that the fatty acid metal salt 4 was changed to the fatty acid metal salt 7 in the production of the toner 5. Table 3 shows the physical properties of the magnetic toner 13.

<Manufacture of toner 14>
In the production of the toner 10, the peripheral speed of the stirring blade of the Henschel mixer was stirred and mixed for 4 minutes at 40 m / sec, and stopped for 1 minute. The mixture was stirred and mixed again at the same peripheral speed for 4 minutes, and stopped for 1 minute. Further, a magnetic toner 14 was obtained in the same manner as in the production of the toner 10 except that stirring and mixing were performed for 4 minutes at the same peripheral speed. Table 3 shows the physical properties of the magnetic toner 14.

<Manufacture of toner 15>
In the production of the toner 13, the magnetic toner 15 was prepared in the same manner as in the production of the toner 13 except that the peripheral speed of the stirring blade of the Henschel mixer was changed to 30 m / sec, and the two stirring / mixing times were changed to 2 minutes. Obtained. Table 3 shows the physical properties of the magnetic toner 15.

<Manufacture of Toner 16>
A magnetic toner 16 was obtained in the same manner as in the production of the toner 9 except that the fatty acid metal salt 4 was changed to the fatty acid metal salt 7 in the production of the toner 9. Table 3 shows the physical properties of the magnetic toner 16.

<Manufacture of toner 17>
In the production of the toner 10, the magnetic toner 17 was obtained in the same manner as in the production of the toner 10 except that the addition amount of the fatty acid metal salt 9 was changed to 0.03 part. Table 3 shows the physical properties of the magnetic toner 17.

<Manufacture of Toner 18>
In the production of the toner 11, a magnetic toner 18 was obtained in the same manner as in the production of the toner 11 except that the addition amount of the fatty acid metal 5 was changed to 0.60 part. Table 3 shows the physical properties of the magnetic toner 18.

<Manufacture of Toner 19>
A magnetic toner 19 was obtained in the same manner as in the production of the toner 10 except that the fatty acid metal salt 9 was changed to the fatty acid metal salt 10 in the production of the toner 10. Table 3 shows the physical properties of the magnetic toner 19.

<Manufacture of toner 20>
A magnetic toner 20 was obtained in the same manner as in the production of the toner 11 except that the fatty acid metal salt 5 was changed to the fatty acid metal salt 8 in the production of the toner 11. Table 3 shows the physical properties of the magnetic toner 20.

<Manufacture of toner 21>
A magnetic toner 21 was obtained in the same manner as in the production of the toner 11 except that the fatty acid metal salt 5 was changed to the fatty acid metal salt 11 in the production of the toner 11. Table 3 shows the physical properties of the magnetic toner 21.

<Manufacture of toner 22>
A magnetic toner 22 was obtained in the same manner as in the production of the toner 11 except that the fatty acid metal salt 5 was changed to the fatty acid metal salt 12 in the production of the toner 11. Table 3 shows the physical properties of the magnetic toner 22.

<Manufacture of toner 23>
(Preparation of resin particle dispersion 1)
Styrene 306 parts n-butyl acrylate 94 parts divinyl benzene 3.6 parts The above components were mixed and dissolved to prepare a solution.

  A solution obtained by dissolving 4 parts of an anionic surfactant in 570 parts of ion-exchanged water was added, emulsified and stirred, and heated to 74 ° C. To this was added 25.0 parts of dilauroyl peroxide, and 6.0 parts of sodium ascorbate was added when the polymerization conversion reached 40%. Thereafter, reaction was performed for 5 hours to obtain a resin particle dispersion 1 having a center particle size of 0.26 μm.

(Preparation of resin particle dispersion 2)
Polyester resin 2 20 parts Ion-exchanged water 200 parts The above components were subjected to a dispersion treatment with a pressure discharge type homogenizer to obtain a resin particle dispersion 2 having a center diameter of 0.19 μm.

(Preparation of magnetic dispersion)
Magnetic body 2 150 parts Nonionic surfactant 10 parts Ion-exchanged water 400 parts The above components were mixed and dissolved, and dispersed with a homogenizer for 30 minutes to obtain magnetic body dispersion liquid 1.

(Preparation of release agent dispersion)
Fischer-Tropsch wax 50 parts Cationic surfactant 5 parts Ion-exchanged water 200 parts The above components are dispersed with a pressure discharge type homogenizer to obtain a release agent dispersion containing release agent particles having a center diameter of 0.16 μm. It was.

(Manufacture of toner)
Resin particle dispersion 1 200 parts Magnetic material dispersion 1 283 parts Release agent dispersion 1 64 parts Polyaluminum chloride 1.23 parts After thoroughly mixing and dispersing the above components with a homogenizer, the mixture is heated to 58 ° C with stirring. did. Then, after maintaining at 58 ° C. for 180 minutes, 30 parts of the resin particle dispersion 2 was further added and stirred.

  Thereafter, the pH in the system was adjusted to 7.0 with a 0.5 mol / l sodium hydroxide aqueous solution, and then heated to 85 ° C. while stirring was continued, followed by stirring for 1 hour. Thereafter, the pH was lowered to 4.0 and held for 6 hours. After completion of the reaction, the mixture was cooled, filtered, sufficiently washed with ion exchange water, filtered, washed, and dried to obtain magnetic toner particles 23.

  100.00 parts of this magnetic toner particle 23, 1.00 parts of hydrophobic silica fine powder having a number average primary particle size of 12 nm, and 0.40 part of fatty acid metal salt 4 are added to a Henschel mixer (Mitsui Miike Chemical Co., Ltd.). It was thrown into. Then, the peripheral speed of the stirring blade was 40 m / sec, and stirring and mixing were performed for 4 minutes. Thereafter, stirring / mixing was stopped for 1 minute, and the stirring blade was further stirred for 4 minutes with a peripheral speed of 40 m / sec to obtain a magnetic toner 23 having a weight average particle diameter (D4) of 7.2 μm. Table 3 shows the physical properties of the magnetic toner 23.

<Manufacture of Toner 24>
-Styrene / n-butyl acrylate copolymer (mass ratio 78/22) 100.0 parts-Iron complex of monoazo dye (T-77: manufactured by Hodogaya Chemical Co., Ltd.) 3.0 parts-Magnetic substance 2 90.0 parts- Fischer-Tropsch wax 15.0 parts The above materials are mixed in a blender, melt kneaded with a twin-screw extruder heated to 130 ° C, the cooled kneaded product is coarsely pulverized with a hammer mill, and the coarsely pulverized product is finely pulverized with a jet mill. After pulverization, the finely pulverized product was subjected to air classification to obtain magnetic toner particles 24.

  100.00 parts of this magnetic toner particle 24, 1.00 parts of hydrophobic silica fine powder having a number average primary particle size of 12 nm, and 0.40 part of fatty acid metal salt 4 are added to a Henschel mixer (Mitsui Miike Chemical Co., Ltd.). It was thrown into. Then, the peripheral speed of the stirring blade was 40 m / sec, and stirring and mixing were performed for 4 minutes. Thereafter, stirring / mixing was stopped for 1 minute, and the stirring blade was rotated and mixed at a peripheral speed of 40 m / sec for 4 minutes to obtain a magnetic toner 24 having a weight average particle diameter (D4) of 7.5 μm. Table 3 shows the physical properties of the magnetic toner 24.

<Manufacture of Toner 25>
The magnetic toner particles 24 obtained by the production of the toner 24 were subjected to a treatment for 3 minutes at 6000 rpm for 3 times using a hybridizer (manufactured by Nara Machinery Co., Ltd.) to obtain magnetic toner particles 25. 100.00 parts of this magnetic toner particle 25, 1.00 parts of hydrophobic silica fine powder having a number average primary particle size of 12 nm, and 0.40 part of fatty acid metal salt 4 are added to a Henschel mixer (Mitsui Miike Chemical Co., Ltd.). It was thrown into. Then, the peripheral speed of the stirring blade was 40 m / sec, and stirring and mixing were performed for 4 minutes. Thereafter, stirring and mixing were stopped for 1 minute, and the stirring blade was rotated and mixed at a peripheral speed of 40 m / sec for 4 minutes to obtain a magnetic toner 25 having a weight average particle diameter (D4) of 7.5 μm. Table 3 shows the physical properties of the magnetic toner 25.

<Example 1>
(Image forming device)
An LBP3100 (manufactured by Canon) was used as an image forming apparatus, and the number of printed sheets was changed from 16 sheets / minute to 20 sheets / minute. Further, the contact pressure of the cleaning blade was changed from 4 kgf / m to 8 kgf / m. The durability is strictly evaluated by changing the number of printed sheets to 20 / min, and the stop stripe can be strictly evaluated by increasing the cleaning blade pressure.

  Using this modified machine, toner 1 is used, and the printing rate is 2% in a low temperature and normal humidity environment (15 ° C./10% RH) and in a high temperature high humidity environment (32.5 ° C./80% RH). The horizontal line was subjected to a test for printing 1500 sheets in intermittent mode. After that, it was left for 1 day in each environment, and 1500 images were printed. After 3000 images were printed, they were left in each environment for 1 day to perform further images.

  As a result, in each environment, the density was high before and after the durability test, and a uniform image without fogging on the non-image area could be obtained. In addition, there was no defective cleaning throughout the durability, there were no stop streaks, and a good image could be obtained.

  Table 4 shows the evaluation results in a low temperature and low humidity environment, and Table 5 shows the evaluation results in a high temperature and high humidity environment.

  The evaluation methods for each evaluation performed in the examples and comparative examples of the present invention and the judgment criteria thereof will be described below.

<Image density>
The image density formed a solid image portion, and the density of the solid image was measured with a Macbeth reflection densitometer (manufactured by Macbeth).

<Fog>
A white image was output, and the reflectance was measured using a REFECTMETER MODEL TC-6DS manufactured by Tokyo Denshoku. On the other hand, the reflectance of the transfer paper (standard paper) before white image formation was measured in the same manner. A green filter was used as the filter. The fog was calculated from the reflectance before and after the white image output using the following formula.
Fog (reflectance) (%) = reflectance of standard paper (%)-reflectance of white image sample (%)

The determination criteria for fogging are as follows.
A: Very good (less than 1.5%)
B: Good (1.5% or more and less than 2.5% or less)
C: Normal (2.5% or more and less than 4.0% or less)
D: Poor (4% or more)

<Poor cleaning>
With respect to all the horizontal line images during durability, the level of cleaning failure was visually judged based on the following criteria based on the following criteria.
A: No cleaning failure occurred B: An extremely slight cleaning failure occurred C: An image having a slight cleaning failure but no problem in practical use.
D: An image in which poor cleaning occurs and is not preferable for practical use.

<Stop line>
The stop streaks were left for 1 day after endurance, and then 5 halftone images were printed, and the level of the stop streaks was visually determined according to the following criteria.
A: Stop streak is not generated B: Very slight stop streak is generated C: Stop streak is slightly generated, but there is no practical problem.
D: Stop streak has occurred, and this is an image that is not preferable in practice

<Examples 2 to 16>
An image formation test was conducted in the same manner as in Example 1 except that toners 2 to 16 were used. As a result, an image with a level that is practically satisfactory before and after the endurance test was obtained for each toner. Table 4 shows the evaluation results in a low temperature and low humidity environment, and Table 5 shows the evaluation results in a high temperature and high humidity environment.

<Comparative Examples 1 to 9>
The image output test was performed in the same manner as in Example 1 except that the toners 17 to 25 were used. As a result, all of the toners 17 and 19 to 25 had stop streaks in a high temperature and high humidity environment, and the toner 18 had poor fog in a low temperature and low humidity environment. Table 4 shows the evaluation results in a low temperature and low humidity environment, and Table 5 shows the evaluation results in a high temperature and high humidity environment.

  DESCRIPTION OF SYMBOLS 100 Electrostatic latent image carrier (photoreceptor), 102 Toner carrier, 114 Transfer member (transfer roller), 116 Cleaner, 117 Contact charging member (charge roller), 121 Laser generator (latent image forming means, exposure device) , 123 laser, 124 register roller, 125 transport belt, 126 fixing device, 140 developing device, 141 stirring member

Claims (7)

A magnetic toner containing magnetic toner particles containing at least a binder resin and a magnetic material, and a fatty acid metal salt,
The fatty acid metal salt is contained in an amount of 0.05 to 0.50 parts by mass with respect to 100 parts by mass of the magnetic toner particles.
Median diameter in volume-based of the fatty acid metal salt (D50) is, is at 0.15μm or 0.65μm or less,
The magnetic toner has a compression ratio obtained from the following formula (1) of 30 or less,
Formula (1) Compression rate = {1− (apparent density / tap density)} × 100
A magnetic toner wherein the surface free energy of the magnetic toner is 40.0 mJ / m ² or less. The magnetic toner according to claim 1, wherein the liberation rate of the fatty acid metal salt from the magnetic toner particles is 10.0% by mass or more and 40.0% by mass or less. A magnetic toner according to claim 1 or 2, wherein the median size (D50) of the volume-based fatty acid metal salt, and wherein the at least 0.30 .mu.m 0.60 .mu.m or less. The magnetic toner according to claim 1, wherein the magnetic toner particles have a core-shell structure, and the shell layer in the core-shell structure contains at least a polyester resin. A magnetic toner according to claim 4 wherein the glass transition point (Tg) of the polyester resin, characterized in that at 75 ° C. or higher 90 ° C. or less. 6. The magnetic toner according to claim 4, wherein, in the monomer component constituting the polyester resin, 80 mol% or more of the alcohol component is a propylene oxide adduct of bisphenol A having an average addition mole number of 2 mol .   The magnetic toner according to claim 1, wherein the magnetic toner particles are produced by a suspension polymerization method.

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