JP3947194B2 - Method for producing toner for electrophotography - Google Patents

Description

  The present invention relates to a method for producing an electrophotographic toner for revealing an electrostatic charge image formed on the surface of a photoreceptor in electrophotography, electrostatic recording, electrostatic printing, etc., a developer using the toner, and the toner The present invention relates to a developing method using the toner, a developing device using the toner, a toner container filled with the toner, and a developer container filled with the developer.

  A method of visualizing image information through an electrostatic latent image by using an image forming apparatus using an electrophotographic method or an electrostatic recording method is currently used in various fields. For example, in electrophotography, image information is formed into an electrostatic latent image on a photoreceptor by an exposure process subsequent to a charging process, visualized with a developer, and then passed through a transfer process and a fixing process. Is played. In this case, the developer includes a one-component developer using a magnetic toner or a non-magnetic toner alone, and a two-component developer composed of a toner and a carrier.

  The electrophotographic toner used in such a developer is usually melt-kneaded with a thermoplastic resin together with a pigment and, if necessary, a release agent such as wax or a charge control agent, and then finely pulverized and further classified. Manufactured by a kneading and pulverizing method. In the toner thus obtained, if necessary, inorganic or organic fine particles are added to the toner particle surface in order to improve fluidity and cleaning properties.

  The toner obtained by the usual kneading and pulverization method is generally indeterminate, its particle size distribution is broad, its fluidity is low, its transferability is low, its fixing energy is high, and its charge amount is between the toner particles. There was a problem that it was non-uniform and charging stability was low. Furthermore, the image obtained from such toner is still unsatisfactory in image quality.

  On the other hand, in order to overcome the problems of the toner by the kneading and pulverizing method, a method for producing the toner by the polymerization method has been proposed. Since this method does not include a pulverization step, the toner does not require a kneading step and a pulverization step, which contributes to cost savings such as energy saving, production time reduction, and product yield improvement. large. In addition, the particle size distribution in the polymerized toner particles obtained by such a polymerization method is easy to form a sharp distribution as compared with the particle size distribution of the toner by the pulverization method, and it is easy to encapsulate the wax. It is possible to greatly improve the performance. It is also easy to obtain a spherical toner.

  However, there are many problems that have not yet been solved in the toner produced by the polymerization method. Since the toner obtained by the polymerization method has surface tension in the polymerization process, the sphericity of the particles is higher than that of the kneading and pulverization method, but the toner physical properties are still insufficient. In this method, it is not easy to control (atypical) the shape of the toner. However, this method is advantageous in terms of charging stability and transferability.

  In the production method of toner by suspension polymerization method widely used in the polymerization method, the monomer for binder (binder resin) used in the method is limited to styrene monomer and acrylic monomer which are harmful to human body. Since the toner to be contained contains these components, there is an environmental problem. In addition, since the resulting toner encapsulates wax, when the toner is used in practice, the adhesion of the toner to the photoreceptor is reduced, but with regard to toner fixing properties, the wax exists in the form of a particle interface. Compared with the pulverization method, the encapsulated part makes it difficult for the wax to permeate the toner surface, resulting in poor fixing efficiency. Therefore, the polymerized toner becomes a disadvantageous toner for power consumption. Further, in the case of a polymerized toner, if the amount of wax is increased in order to improve the fixing property, or if the dispersed particle diameter of the wax is increased, the transparency of the color image is deteriorated when used as a color toner. It is unsuitable for use as a forming toner.

  As a method for producing the polymerized toner, there are an emulsion polymerization method and the like in which atypical modification is relatively possible in addition to the suspension polymerization method. In the emulsion polymerization method, the monomer is limited to the styrene monomer. Also in this method, the complete removal of the unreacted monomer from the toner particles and the complete removal of the emulsifier and the dispersant from the toner particles are difficult, and environmental problems due to the toner are also generated.

  A solution suspension method is known as a toner production method. In this method, there is a merit that a polyester resin that can be fixed at low temperature can be used, but in this method, since the high molecular weight component is added in the process of dissolving or dispersing the low temperature fixing resin and the colorant in the solvent, the liquid viscosity As a result, productivity problems will occur. Furthermore, in this dissolution suspension method, the toner surface shape is spherical and the surface is made uneven to improve toner cleaning (Patent Document 1). However, such toner has regularity. Since the toner is an irregularly shaped toner, there are problems in terms of charging stability, durability and releasability, and satisfactory toner quality is not obtained.

  According to Patent Document 2, a practical sphericity composed of an elongation reaction product of a urethane-modified polyester as a toner binder for the purpose of improving toner fluidity, low-temperature fixability, and hot offset property is 0.90 to 1. 00 dry toner has been proposed. Further, Patent Documents 3 and 4 disclose dry toners that are excellent in powder flowability and transferability in the case of a small particle size toner, and also excellent in all of heat-resistant storage stability, low-temperature fixability, and hot offset resistance. Has been. The toner production methods described in these publications include a high molecular weight process in which an isocyanate group-containing polyester prepolymer is subjected to a polyaddition reaction with an amine in an aqueous medium.

However, in the case of a polymerized toner obtained by the polymerization method as described above, the dispersion of the pigment is poor, and the pigment is unevenly dispersed in the toner. Therefore, the image obtained with this toner has low transparency. The problem was that it was inferior in saturation (brightness). In particular, when a color image was formed on an OHP sheet using the toner, there was a defect that the image became a dark image.
Japanese Patent Laid-Open No. 9-15903 Japanese Patent Laid-Open No. 11-133665 JP-A-11-149180 JP 2000-292981 A

  In the toner for electrophotography using a polyester resin as a binder, the present invention provides a high-quality image excellent in transparency and saturation (brightness and gloss) in which a pigment-based colorant is highly dispersed. An electrophotographic toner excellent in body fluidity, hot offset resistance, charging stability and transferability is provided. Further, a developer using the toner, a developing method using the toner, a developing device using the toner, It is an object of the present invention to provide a toner container filled with toner and a developer container filled with the developer.

As a result of intensive studies to solve the above problems, the present inventors have completed the present invention. That is, according to the present invention, the following toner, developer, developing method, developing device, toner container, and developer container are provided.
(1) Oiliness in which at least a polyester-based prepolymer containing an isocyanate group is dissolved in an organic solvent, a pigment-based colorant added as masterbatch colorant particles is dispersed, and a release agent is dissolved or dispersed. obtaining an aqueous dispersion by dispersing in an aqueous medium a dispersion liquid in the presence of inorganic particles and / or polymer fine particles, monoamines with polyamine and / or an active hydrogen-containing group of the prepolymer in the aqueous dispersion electrons with the step of obtaining an electrophotographic toner by removing the liquid medium from step you forming a urea-modified polyester resin having a urea group by Rukoto reacted and the aqueous dispersion containing the urea-modified polyester resin and a method of manufacturing a toner, pigment colorant dispersed in the toner for electrophotography, the number Hitoshi径is at 0.3 [mu] m or less state, and are the ratio of particles diameter is 0.7μm or 5% by number or less, a particle size in a proportion of particles having a 0.5μm or 10% by number or less A method for producing an electrophotographic toner, comprising:
(2) the oil dispersions, method of manufacturing toner for electrophotography described in (1) that has been obtained by further wet grinding.
(3) the electrophotographic toner has a weight-average particle diameter of 3.0～7.0Myuemu, wherein the ratio of the weight average particle diameter to number average particle diameter of 1.00 to 1.20 The method for producing an electrophotographic toner according to ( 1 ) or (2) .
( 4 ) The method for producing an electrophotographic toner according to any one of ( 1 ) to (3) , wherein the electrophotographic toner has a circularity of 0.900 to 0.960.
(5) tetrahydrofuran-soluble matter of the polyester resin contained in the toner for electrophotography has a main peak in the region molecular weight of 2500 - 10000, and wherein the number average molecular weight of 2,500 to 50,000 The method for producing an electrophotographic toner according to any one of ( 1 ) to (4) .
(6) polyester resin contained in the toner for electrophotography has a glass transition point is 40 to 65 ° C., an acid value characterized in that it is a 1~30mgKOH / g (1) ~ ( 5) The method for producing an electrophotographic toner according to any one of the above.
(7) The oil dispersions, in any one of wherein the monoamine and nonreactive polyester resin having the polyamine and / or an active hydrogen-containing group is dissolved (1) - (6) A method for producing the electrophotographic toner according to claim.
( 8 ) A developer comprising a toner obtained by the method for producing a toner according to any one of ( 1 ) to (7) and a carrier.
(9) (1) toner container, characterized in that the toner obtained by the method for producing a toner according to any one of (1) to (7) are filled.
(1 0) developer container developer according to (8), characterized in that it is filled.
(1 1) (1) to a developing method characterized that you developed with the toner obtained by the method for producing a toner according to any one of (7).
(1 2 ) A developing device that performs development using the toner obtained by the toner production method according to any one of ( 1 ) to (7) .
(1 3) developing apparatus characterized by developing with the toner filled in the toner container according to (9).
(1 4) a developing device, which comprises the use of a developer is filled in the developer container according to (10).

  Needless to say, the toner of the present invention can be applied as a black and white toner and a color toner.

  The toner of the present invention is a toner having both high image quality, high definition image, low-temperature fixing property and hot offset property, and the image has excellent transparency and good quality, and is sufficient when a full color image is formed on OHP paper. Transparency is obtained.

  Further, the toner of the present invention is a toner excellent in charging stability and color reproducibility.

  In the toner of the present invention, an oily dispersion liquid in which at least a polyester-based prepolymer A containing an isocyanate group is dissolved in an organic solvent, a pigment-based colorant is dispersed, and a release agent is dissolved or dispersed in an aqueous medium. A urea-modified polyester having a urea group which is dispersed in the presence of inorganic fine particles and / or polymer fine particles, and in which the prepolymer A is reacted with a polyamine and / or a monoamine B having an active hydrogen-containing group. It is obtained by forming a resin C and removing the liquid medium contained in the dispersion containing the urea-modified polyester resin C.

  In the urea-modified polyester resin C, the Tg is 40 to 65 ° C, preferably 45 to 60 ° C. The number average molecular weight Mn is 2500 to 50000, preferably 2500 to 30000. The weight average molecular weight Mw is 10,000 to 500,000, preferably 30,000 to 100,000.

  This toner contains, as a binder resin, a urea-modified polyester resin C having a urea bond that has been polymerized by the reaction between the prepolymer A and the amine B. The colorant is highly dispersed in the binder resin.

As a result of intensive studies on the toner, the present inventors have determined that the dispersed particle size of the pigment-based colorant contained in the toner particles is 0.5 μm or less in number average particle size, and that the particle size is 0.00. By controlling the number ratio of 7 μm or more to 5% or less, color images with excellent low-temperature fixability, charging stability and fluidity, as well as giving high-quality images, especially excellent transparency and glossiness. It has been found that a toner that gives a toner can be obtained.

The present inventors have found that further discussed, as well as defined below 0.3μm diameter of dispersed particles colorant in number average diameter, by the particle size to control the number ratio of more than 0.5μm below 10% It was also found that a higher quality toner can be obtained. Such a toner has excellent image resolving power and is suitable as a toner for a digital developing device. In particular, in the case of the color toner according to the present invention, a high-quality color image having excellent resolution and transparency and good color reproducibility is provided.

  In order to obtain the toner in which the colorant according to the present invention is uniformly dispersed, it is necessary to devise the toner production conditions. Under the conventional production conditions, it is impossible to obtain a high-quality toner as described above.

  In the case of the present invention, in order to obtain the high-quality toner, a step of pulverizing the colorant (wet pulverization step) is employed when forming an oily dispersion liquid containing the prepolymer A, the colorant and the release agent. is required. The wet pulverization apparatus for carrying out the wet pulverization process in this case may be any apparatus that can pulverize by applying an impact force to the colorant in the liquid, and any apparatus can be used. As such a thing, various conventionally well-known wet grinding apparatuses, for example, a ball mill, a bead mill, etc. are mentioned.

  In the wet pulverization step, the temperature is 5 to 20 ° C, preferably 15 to 20 ° C.

  By adjusting the wet pulverization conditions, the dispersed particle size and particle size distribution of the colorant contained in the toner particles can be controlled within the above range.

  The wet pulverization step can also be applied to the dispersion after the reaction, if necessary.

  Furthermore, in the case of the present invention, in order to obtain the high-quality toner, a method of adding a master batch colorant particle in which a colorant is dispersed in a resin at a high concentration as a colorant material in an organic solvent, and stirring and dispersing is used. It can preferably be employed. By using the master batch particles, it is possible to obtain a toner that gives a color image with good transparency in which a colorant having a small dispersed particle diameter is uniformly dispersed.

  In order to preferably produce such masterbatch colorant particles, a mixture of a heat-meltable resin and a colorant is kneaded with a high shearing force at the melting temperature of the resin, and the resulting kneaded product is cooled and solidified. This solidified product is pulverized.

  As the resin, a thermoplastic resin having good miscibility with the urea-modified polyester resin C derived from the prepolymer A is used. In the case of the present invention, a polyester resin is preferably used. In the said thermoplastic resin, the softening point is 100-200 degreeC, Preferably it is 120-160 degreeC, and the number average molecular weight Mn is 2500-5000, Preferably it is 2500-30000.

  The colorant concentration in the masterbatch colorant particles is 10 to 60% by weight, preferably 25 to 55% by weight.

  Next, a method for measuring toner physical properties such as the dispersed particle diameter of the pigment-based colorant in the toner will be described in detail.

  In order to measure the dispersed particle size and particle size distribution of the colorant in the toner, a measurement sample in which the toner is embedded in an epoxy resin and the toner is ultrathinned to about 100 nm with a microtome MT6000-XL (Keiwa Corporation). Prepare.

  Using an electron microscope (H-9000NAR manufactured by Hitachi, Ltd.), a plurality of TEM photographs were taken at an acceleration voltage of 100 kV at a magnification of 10,000 to 40000 times, and the image information was obtained with an image processing analyzer LUZEX III of IMAGE ANALYZER. Convert to image data. For the target pigment-based colorant particles, the measurement is repeated for particles having a particle size of 0.1 μm or more until sampling exceeds 300 times, and the average particle size and particle size (particle size) distribution are obtained.

  In the toner of the present invention, the weight average particle diameter (Dv) is 3 to 7 μm, and the ratio (Dv / Dn) to the number average particle diameter (Dn) is 1.00 ≦ Dv / Dn ≦ 1.20. is there. By defining Dv / Dn in this way, it is possible to obtain a toner with high resolution and high image quality. In order to obtain a higher quality image, the colorant has a weight average particle diameter (Dv) of 3 to 7 μm and a ratio (Dv / Dn) to the number average particle diameter (Dn) of 1.00 ≦ Dv / Dn ≦ 1.20, and particles having a size of 3 μm or less should be 1 to 10% by number, and more preferably, the weight average particle size is 3 to 6 μm, and Dv / Dn is 1.00 ≦ Dv. /Dn≦1.15 is preferable. Such a toner is excellent in all of heat-resistant storage stability, low-temperature fixability, and hot offset resistance, and particularly excellent in image gloss when used in a full-color copying machine. Even if the toner balance is extended over a wide range, fluctuations in the particle size of the toner in the developer are reduced, and good and stable developability can be obtained even with long-term stirring in the developing device.

  In general, it is said that the smaller the toner particle size, the more advantageous it is to obtain a high-resolution and high-quality image, but conversely, it is disadvantageous for transferability and cleaning properties. It is. Further, when the volume average particle diameter of the toner is smaller than the range specified in the present invention, the toner is fused to the surface of the carrier in the two-component developer during long-term agitation in the developing device, and the charging ability of the carrier is lowered. . On the other hand, when used as a one-component developer, toner filming on the developing roller and toner fusion to a member such as a blade for thinning the toner are likely to occur. These phenomena are greatly related to the content of fine powder in the toner. In particular, when the content of particles of 3 μm or less exceeds 10%, the toner hardly adheres to the carrier and the charging stability at a high level. It becomes difficult to plan.

  Conversely, when the toner particle size is larger than the range specified in the present invention, it becomes difficult to obtain a high-resolution and high-quality image, and the balance of the toner in the developer is performed. In many cases, the variation in the particle diameter of the toner increases. It was also clarified that the same was true when the weight average particle diameter / number average particle diameter was larger than 1.20.

  The average particle diameter and the particle size distribution of the toner are measured by a car Coulter counter method. Examples of the measuring device for the particle size distribution of toner particles include Coulter Counter TA-II and Coulter Multisizer II (both manufactured by Coulter). In the present invention, a Coulter counter TA-II type was used, and an interface for outputting number distribution and volume distribution (manufactured by Nikka Giken Co., Ltd.) and a PC 9801 personal computer (manufactured by NEC) were connected and measured.

  Next, a method for measuring the toner number distribution and volume distribution will be described.

  First, 0.1 to 5 ml of a surfactant (preferably alkylbenzene sulfonate) is added as a dispersant to 100 to 150 ml of an aqueous electrolytic solution. Here, the electrolytic solution is an approximately 1% NaCl aqueous solution formed using primary sodium chloride. For example, ISOTON-II (manufactured by Coulter) can be used. Here, 2 to 20 mg of a measurement sample is further added. The electrolytic solution in which the sample is suspended is subjected to a dispersion process for about 1 to 3 minutes with an ultrasonic disperser, and the volume and the number of toner particles are measured with the measuring device using a 100 μm aperture as the aperture, and the volume distribution is obtained. And calculate the number distribution.

  As channels, 2.00 to less than 2.52 μm; 2.52 to less than 3.17 μm; 3.17 to less than 4.00 μm; 4.00 to less than 5.04 μm; 5.04 to less than 6.35 μm; 6 Less than 35 to 8.00 μm; less than 8.00 to less than 10.08 μm; less than 10.08 to less than 12.70 μm; less than 12.70 to less than 16.00 μm; less than 16.00 to less than 20.20 μm; Uses 13 channels of less than 40 μm; 25.40 to less than 32.00 μm; 32.00 to less than 40.30 μm, and targets particles having a particle size of 2.00 μm to less than 40.30 μm. The ratio Dv / Dn was determined from the volume-based weight average particle diameter (Dv) determined from the volume distribution related to the toner of the present invention and the number average particle diameter (Dn) determined from the number distribution.

  Regarding the hot offset resistance of the toner, various studies have been conducted so far including control of the molecular weight distribution of the binder resin. As a method for achieving both conflicting properties such as low temperature fixability and hot offset resistance, a method using a binder resin having a wide molecular weight distribution, a high molecular weight component having a molecular weight of several hundred thousand to several million, and a molecular weight There is a method using a mixed resin having at least two molecular weight peaks including several thousand to several tens of thousands of low molecular weight components. When the high molecular weight component has a crosslinked structure or is in a gel state, it is more effective for hot offset. However, in a full-color toner that requires glossiness and transparency, it is not preferable to introduce a large amount of a high molecular weight component. In the case of the present invention, since the toner contains a high molecular weight urea-modified polyester resin having a urea bond, it is possible to achieve hot offset resistance while satisfying transparency and gloss.

  The molecular weight distribution of the binder resin component contained in the toner according to the present invention is measured by GPC as follows.

  Stabilize the column in a 40 ° C. heat chamber, flow THF at a flow rate of 1 ml / min as a column solvent at this temperature, and prepare a THF sample solution of resin adjusted to a sample concentration of 0.05 to 0.6% by weight. Perform the measurement operation by injecting ~ 200 μl.

In measuring the molecular weight of the sample, the molecular weight distribution of the sample is calculated from the relationship between the logarithmic value of a calibration curve prepared from several monodisperse polystyrene standard samples and the number of counts. As a standard polystyrene sample for preparing a calibration curve, Pressure Chemical Co. Or the molecular weights made by Toyo Soda Kogyo Co., Ltd. are 6 × 10 ² , 2.1 × 10 ² , 4 × 10 ² , 1.75 × 10 ⁴ , 1.1 × 10 ⁵ , 3.9 × 10 ⁵ , 8.6. Use x10 ⁵ , 2 × 10 ⁶ , 4.48 × 10 ⁶ , and use at least about 10 standard polystyrene samples. An RI (refractive index) detector is used as the detector.

  The main peak molecular weight in the molecular weight distribution of the binder component contained in the toner is usually 2500 to 10,000, preferably 2500 to 8000, and more preferably 2500 to 6000. When the amount of the component having a molecular weight of less than 1000 increases, the heat resistant storage stability tends to deteriorate. On the other hand, when the component having a molecular weight of 30000 or more increases, the low-temperature fixability tends to decrease, but the decrease can be suppressed as much as possible by balance control. The content of components having a molecular weight of 30000 or more is 1% to 10%, and varies depending on the toner material, but is preferably 3 to 6%. If it is less than 1%, sufficient hot offset resistance cannot be obtained, and if it exceeds 10%, glossiness and transparency are deteriorated.

  The Mn of the binder resin contained in the toner is 2500 to 50000, and the value of Mw / Mn is 10 or less. When it exceeds 10, sharp melt property is lacking and glossiness is impaired.

  The circularity of the toner of the present invention is measured by a flow type particle image analyzer FPIA-2000 (manufactured by Sysmex Corporation).

  In the toner of the present invention, the average circularity is 0.900 to 0.960, and it is important that the toner of the present invention has a specific shape and shape distribution. When the average circularity is less than 0.900, the toner exhibits an irregular shape and does not give satisfactory transferability and high-quality images without dust. Since the irregularly shaped toner particles have many contact points with the smooth medium on the photosensitive member and the charge concentrates on the tip of the protrusion, the van der Waals force and the mirror image force are higher than those of the relatively spherical particles. Therefore, in the electrostatic transfer process, the spherical particles are selectively moved in the toner in which the amorphous particles and the spherical particles are mixed, and the character portion and the line portion image are lost. In addition, the remaining toner must be removed for the next development process, and there is a problem that a cleaner device is required or the toner yield (the ratio of toner used for image formation) is low. . The circularity of the pulverized toner is usually 0.910 to 0.920 when measured with this apparatus.

  As a method for measuring the toner shape (circularity), an optical detection zone method is used in which a suspension containing particles is passed through an imaging zone detection zone on a flat plate, and a particle image is optically detected and analyzed by a CCD camera. Is appropriate. In this method, the projected area of the particle can be obtained. The circularity is a value obtained by dividing the circumference of an equivalent circle having the same area as the projected area by the circumference of the actual particle. This value is a value measured as an average circularity by a flow type particle image analyzer FPIA-2000. As a specific measuring method, 0.1 to 0.5 ml of a surfactant, preferably alkylbenzene sulfonate is added as a dispersant to 100 to 150 ml of water from which impure solids have been removed in advance, and further measurement is performed. Add about 0.1-0.5g of sample. The suspension in which the sample is dispersed is subjected to dispersion treatment with an ultrasonic disperser for about 1 to 3 minutes, and the concentration of the dispersion is set to 3000 to 10,000 / μl, and the shape of the toner and the shape distribution of the toner are measured by the above-described apparatus.

  The method for producing the toner of the present invention includes a high molecular weight process in which an isocyanate group-containing polyester prepolymer A dispersed in an aqueous medium containing inorganic fine particles and / or polymer fine particles is reacted with amine B. In this case, the polyester prepolymer (A) containing an isocyanate group is a polycondensate of a polyol (PO) and a polycarboxylic acid (PC), and a polyester having an active hydrogen group is further reacted with a polyisocyanate (PIC). Can be obtained. In this case, examples of the active hydrogen group of the polyester include a hydroxyl group (alcoholic hydroxyl group and phenolic hydroxyl group), an amino group, a carboxyl group, a mercapto group, and the like. Among these, an alcoholic hydroxyl group is preferable.

  Examples of the polyol (PO) include diol (DIO) and trivalent or higher polyol (TO), and (DIO) alone or a mixture of (DIO) and a small amount of (TO) is preferable. Diol (DIO) includes alkylene glycol (ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,6-hexanediol, etc.); alkylene ether glycol (diethylene glycol, triethylene glycol, Ethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol, etc.); alicyclic diols (1,4-cyclohexanedimethanol, hydrogenated bisphenol A, etc.); bisphenols (bisphenol A, bisphenol F, Bisphenol S, etc.); alkylene oxide (ethylene oxide, propylene oxide, butylene oxide, etc.) adduct of the above alicyclic diol; Alkylene oxide phenol compound (ethylene oxide, propylene oxide, butylene oxide, etc.), etc. adducts. Among them, preferred are alkylene glycols having 2 to 12 carbon atoms and alkylene oxide adducts of bisphenols, and particularly preferred are alkylene oxide adducts of bisphenols and alkylene glycols having 2 to 12 carbon atoms. It is a combined use. Examples of the trivalent or higher polyol (TO) include 3 to 8 or higher polyhydric aliphatic alcohols (glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, sorbitol, etc.); trivalent or higher phenols (Tris) Phenol PA, phenol novolak, cresol novolak, etc.); alkylene oxide adducts of the above trivalent or more polyphenols.

  Examples of the polycarboxylic acid (PC) include dicarboxylic acid (DIO) and trivalent or higher polycarboxylic acid (TC), and (DIO) alone and a mixture of (DIO) and a small amount of (TC) are preferable. Dicarboxylic acids (DIO) include alkylene dicarboxylic acids (succinic acid, adipic acid, sebacic acid, etc.); alkenylene dicarboxylic acids (maleic acid, fumaric acid, etc.); aromatic dicarboxylic acids (phthalic acid, isophthalic acid, terephthalic acid, naphthalene) Dicarboxylic acid and the like). Of these, preferred are alkenylene dicarboxylic acids having 4 to 20 carbon atoms and aromatic dicarboxylic acids having 8 to 20 carbon atoms. Examples of the trivalent or higher polycarboxylic acid (TC) include aromatic polycarboxylic acids having 9 to 20 carbon atoms (such as trimellitic acid and pyromellitic acid). In addition, as polycarboxylic acid (PC), you may make it react with a polyol (PO) using the above-mentioned acid anhydride or lower alkyl ester (Methyl ester, ethyl ester, isopropyl ester, etc.).

  The ratio of the polyol (PO) and the polycarboxylic acid (PC) is usually 2/1 to 1/1, preferably 1 as the equivalent ratio [OH] / [COOH] of the hydroxyl group [OH] and the carboxyl group [COOH]. 5/1 to 1/1, more preferably 1.3 / 1 to 1.02 / 1.

  Examples of the polyisocyanate (PIC) include aliphatic polyisocyanates (tetramethylene diisocyanate, hexamethylene diisocyanate, 2,6-diisocyanatomethylcaproate, etc.); alicyclic polyisocyanates (isophorone diisocyanate, cyclohexylmethane diisocyanate, etc.); Aromatic diisocyanates (tolylene diisocyanate, diphenylmethane diisocyanate, etc.); araliphatic diisocyanates (α, α, α ′, α′-tetramethylxylylene diisocyanate, etc.); isocyanurates; the polyisocyanates are phenol derivatives, oximes, caprolactams And a combination of two or more of these.

  When obtaining a polyester-based prepolymer having an isocyanate group, the ratio of the polyisocyanate (PIC) to the polyester-based resin (PE) having active hydrogen is such that the isocyanate group [NCO] and the hydroxyl group [OH] of the polyester having a hydroxyl group are The equivalent ratio [NCO] / [OH] is usually 5/1 to 1/1, preferably 4/1 to 1.2 / 1, and more preferably 2.5 / 1 to 1.5 / 1. When [NCO] / [OH] exceeds 5, low-temperature fixability deteriorates. When the molar ratio of [NCO] is less than 1, when a modified polyester is used, the urea content in the ester becomes low and the hot offset resistance deteriorates. The content of the polyisocyanate (PIC) component in the prepolymer (A) having an isocyanate group at the terminal is usually 0.5 to 40% by weight, preferably 1 to 30% by weight, more preferably 2 to 20% by weight. It is. If it is less than 0.5% by weight, the hot offset resistance deteriorates, and it is disadvantageous in terms of both heat-resistant storage stability and low-temperature fixability. On the other hand, if it exceeds 40% by weight, the low-temperature fixability deteriorates.

  The number of isocyanate groups contained per molecule in the polyester-based prepolymer (A) having an isocyanate group is usually 1 or more, preferably 1.5 to 3 on average, more preferably 1.8 to 2 on average. Five. If it is less than 1 per molecule, the molecular weight of the resulting urea-modified polyester will be low, and the hot offset resistance will deteriorate.

  As the amine (B), a polyamine and / or a monoamine having an active hydrogen-containing group is used. In this case, the active hydrogen-containing group includes a hydroxyl group and a mercapto group. Such amines include diamine (B1), tri- or higher polyamine (B2), aminoalcohol (B3), aminomercaptan (B4), amino acid (B5), and amino acids B1-B5 blocked ( B6) and the like are included. Examples of the diamine (B1) include aromatic diamines (phenylenediamine, diethyltoluenediamine, 4,4′diaminodiphenylmethane, etc.); alicyclic diamines (4,4′-diamino-3,3′dimethyldicyclohexylmethane, diaminecyclohexane, Isophorone diamine etc.); and aliphatic diamines (ethylene diamine, tetramethylene diamine, hexamethylene diamine etc.) and the like. Examples of the trivalent or higher polyamine (B2) include diethylenetriamine and triethylenetetramine. Examples of amino alcohol (B3) include ethanolamine and hydroxyethylaniline. Examples of amino mercaptan (B4) include aminoethyl mercaptan and aminopropyl mercaptan. Examples of the amino acid (B5) include aminopropionic acid and aminocaproic acid. Examples of the B1 to B5 amino group blocked (B6) include ketimine compounds and oxazoline compounds obtained from the B1 to B5 amines and ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.). Among these amines (B), preferred are B1 and a mixture of B1 and a small amount of B2.

  Furthermore, when the prepolymer A and the amine B are reacted, the molecular weight of the polyester can be adjusted by using an elongation terminator if necessary. Examples of the elongation terminator include monoamines having no active hydrogen-containing groups (diethylamine, dibutylamine, butylamine, laurylamine, and the like), and those blocked (ketimine compounds). The addition amount is appropriately selected in relation to the molecular weight desired for the urea-modified polyester to be produced.

  The ratio between the amine (B) and the prepolymer (A) having an isocyanate group is such that the isocyanate group [NCO] in the prepolymer (A) having an isocyanate group and the amino group [NHx] (x As an equivalent ratio [NCO] / [NHx] of usually 1 to 2, usually 1/2 to 2/1, preferably 1.5 / 1 to 1 / 1.5, more preferably 1.2. /1-1/1.2. When [NCO] / [NHx] is more than 2 or less than 1/2, the molecular weight of the polyester is lowered and the hot offset resistance is deteriorated.

  In the present invention, when the isocyanate group-containing prepolymer A and the amine B are reacted in an aqueous medium, the amine and the non-reactive polyester resin D should be present in the aqueous medium as necessary. Can do. In this polyester resin D, its Tg is 35 to 65 ° C., preferably 45 to 60 ° C., and its Mn is 2000 to 10,000, preferably 2500 to 8000. As this polyester resin D, urea-modified polyester (UMPE) can be used, but this polyester may contain a urethane bond as well as a urea bond. The molar ratio of the urea bond content to the urethane bond content is usually 100/0 to 10/90, preferably 80/20 to 20/80, and more preferably 60/40 to 30/70. When the molar ratio of the urea bond is less than 10%, the hot offset resistance is deteriorated.

  Urea-modified polyester (UMPE) is produced by a known method such as a one-shot method. The weight average molecular weight of the urea modified polyester (UMPE) is usually 10,000 or more, preferably 20,000 to 500,000, and more preferably 30,000 to 100,000. If it is less than 10,000, the hot offset resistance deteriorates.

  In the present invention, the polyester resin modified with the urea bond (UMPE) used as needed is not only used alone, but also contains an unmodified polyester resin (PE) as a toner binder component. It can also be made. The combined use of (PE) improves the low-temperature fixability and the gloss when used in a full-color device, and is more preferable than the case of using (UMPE) alone. Examples of (PE) include polycondensates of polyol (PO) and polycarboxylic acid (PC) similar to the polyester component of (UMPE), and the preferred molecular weight of PE is the same as that of (UMPE). is there. (PE) is not limited to unmodified polyester, but may be modified with a chemical bond other than a urea bond, for example, may be modified with a urethane bond. (UMPE) and (PE) are preferably at least partially compatible with each other in terms of low-temperature fixability and hot offset resistance. Therefore, the polyester component of (UMPE) and (PE) preferably have similar compositions. When (PE) is contained, the weight ratio of (UMPE) to (PE) is usually 5/95 to 80/20, preferably 5/95 to 30/70, more preferably 5/95 to 25/75, Particularly preferred is 7/93 to 20/80. When the weight ratio of (UMPE) is less than 5%, the hot offset resistance is deteriorated, and it is disadvantageous in terms of both heat-resistant storage stability and low-temperature fixability.

  The hydroxyl value of (PE) is preferably 5 or more. The acid value (mgKOH / g) of (PE) is usually 1 to 30, preferably 5 to 20. By giving the acid value, it tends to be negatively charged, and further, the affinity between the paper and the toner when fixing to paper is good, and the low-temperature fixability is improved. However, when the acid value exceeds 30, there is a tendency to deteriorate with respect to the stability of charging, particularly the environmental fluctuation. In the polyaddition reaction between the prepolymer A and the amine B, if the acid value is touched, it will cause blurring in the granulation step, making it difficult to control the emulsification.

  In the present invention, the glass transition point (Tg) of the toner binder is usually 45 to 65 ° C., preferably 45 to 60 ° C. If it is less than 45 ° C., the heat resistance deteriorates, and if it exceeds 65 ° C., the low-temperature fixability becomes insufficient.

  Various conventionally known pigments can be used as the pigment-based colorant used in the present invention. Such as carbon black, nigrosine dye, iron black, naphthol yellow S, Hansa yellow (10G, 5G, G), cadmium yellow, yellow iron oxide, ocher, yellow lead, titanium yellow, polyazo Yellow, Oil Yellow, Hansa Yellow (GR, A, RN, R), Pigment Yellow L, Benzidine Yellow (G, GR), Permanent Yellow (NCG), Vulcan Fast Yellow (5G, R), Tartrazine Lake, Quinoline Yellow Rake, Anthrazan Yellow BGL, Isoindolinone Yellow, Bengala, Red Dan, Lead Zhu, Cadmium Red, Cadmium Mercury Red, Antimony Zhu, Permanent Red 4R, Para Red, Faise Red, Parachlor Ortho Nitroaniline Red , Risorhus Scarlet G, Brilliant Fast Scarlet, Brilliant Carmine BS, Permanent Red (F2R, F4R, FRL, FRLL, F4RH), Fast Scarlet VD, Belkan Fast Rubin B, Brilliant Scarlet G, Resol Rubin GX, Permanent Red F5R, Brilliant Carmine 6B, Pigment Scarlet 3B, Bordeaux 5B, Toluidine Maroon, Permanent Bordeaux F2K, Helio Bordeaux BL, Bordeaux 10B, Bon Maroon Light, Bon Maroon Medium, Eosin Lake, Rhodamine Lake B, Rhodamine Lake Y, Alizarin Lake, Thioindigo Red B, Thioindigo maroon, oil red, quinacridone red, pyrazolone red, polyazo red, chrome bami ON, Benzidine Orange, Perinone Orange, Oil Orange, Cobalt Blue, Cerulean Blue, Alkaline Blue Lake, Peacock Blue Lake, Victoria Blue Lake, Metal Free Phthalocyanine Blue, Phthalocyanine Blue, Fast Sky Blue, Indanthrene Blue (RS, BC ), Indigo, Ultramarine Blue, Bituminous Blue, Anthraquinone Blue, Fast Violet B, Methyl Violet Lake, Cobalt Purple, Manganese Purple, Dioxane Violet, Anthraquinone Violet, Chrome Green, Zinc Green, Chrome Oxide, Pyridian, Emerald Green, Pigment Green B, Naphthol Green B, Green Gold, Acid Green Lake, Malachite Green Lake, Phthalocyanine Green, Anthraquino Green, titanium oxide, zinc white, lithobon and mixtures thereof can be used. The content of the colorant is usually 1 to 15% by weight, preferably 3 to 10% by weight in the toner.

  As described above, the colorant used in the present invention is preferably used as masterbatch colorant particles combined with a resin.

  The binder resin kneaded together with the colorant in the production of the masterbatch includes, in addition to the above-mentioned modified and unmodified polyester resins, styrene such as polystyrene, poly p-chlorostyrene, and polyvinyltoluene, and substitution products thereof. Polymer: Styrene-p-chlorostyrene copolymer, styrene-propylene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-methyl acrylate copolymer, styrene-ethyl acrylate Copolymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, styrene -Α-chloromethyl methacrylate copolymer, Tylene-acrylonitrile copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile-indene copolymer, styrene-maleic acid copolymer, styrene-maleic acid Styrene copolymers such as acid ester copolymers; polymethyl methacrylate, polybutyl methacrylate, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, polyester, epoxy resin, epoxy polyol resin, polyurethane, polyamide, polyvinyl butyral, poly Examples thereof include acrylic resin, rosin, modified rosin, terpene resin, aliphatic or alicyclic hydrocarbon resin, and aromatic petroleum resin. These resins are used alone or in combination.

  The masterbatch can be obtained by mixing and kneading the masterbatch resin and the colorant under high shearing force. At this time, an organic solvent can be used to enhance the interaction between the colorant and the resin. In addition, a so-called flushing method, which is a wet cake of a colorant, is a method of mixing and kneading an aqueous paste containing water of a colorant together with a resin and an organic solvent, transferring the colorant to the resin side, and removing moisture and organic solvent components. Can be used as it is, so that it is not necessary to dry and is preferably used. For mixing and kneading, a high shear dispersion device such as a three-roll mill is preferably used.

  The toner of the present invention contains a release agent (wax) together with a toner binder and a colorant. Various conventionally known waxes can be used as this wax. Examples of such materials include polyolefin waxes (polyethylene wax, polypropylene wax, etc.); long chain hydrocarbons (paraffin wax, sazol wax, etc.); carbonyl group-containing waxes, and the like. Of these, carbonyl group-containing waxes are preferred. Carbonyl group-containing waxes include polyalkanoic acid esters (carnauba wax, montan wax, trimethylolpropane tribehenate, pentaerythritol tetrabehenate, pentaerythritol diacetate dibehenate, glycerin tribehenate, 1,18 -Octadecanediol distearate, etc.); polyalkanol esters (trimellitic acid tristearyl, distearyl maleate, etc.); polyalkanoic acid amides (ethylenediamine dibehenyl amide, etc.); polyalkylamides (trimellitic acid tristearyl amide, etc.) And dialkyl ketones (such as distearyl ketone). Among these carbonyl group-containing waxes, polyalkanoic acid esters are preferred. The melting point of the wax is usually 40 to 160 ° C, preferably 50 to 120 ° C, more preferably 60 to 90 ° C. A wax having a melting point of less than 40 ° C. has an adverse effect on heat resistant storage stability, and a wax having a melting point of more than 160 ° C. tends to cause a cold offset when fixing at a low temperature. Further, the melt viscosity of the wax is preferably 5 to 1000 cps, more preferably 10 to 100 cps as a measured value at a temperature 20 ° C. higher than the melting point. Waxes exceeding 1000 cps have poor effects for improving hot offset resistance and low-temperature fixability. The content of the wax in the toner is usually 0 to 40% by weight, preferably 3 to 30% by weight.

  The toner of the present invention may contain a charge control agent as necessary. Various known charge control agents can be used. Examples include nigrosine dyes, triphenylmethane dyes, chromium-containing metal complex dyes, molybdate chelate pigments, rhodamine dyes, alkoxy amines, quaternary ammonium salts (fluorine-modified quaternary ammonium salts). ), Alkylamide, phosphorus simple substance or compound, tungsten simple substance or compound, fluorine-based activator, salicylic acid metal salt, metal salt of salicylic acid derivative, and the like. Specifically, Nitronine-based dye Bontron 03, quaternary ammonium salt Bontron P-51, metal-containing azo dye Bontron S-34, oxynaphthoic acid metal complex E-82, salicylic acid metal complex E- 84, E-89 of phenol-based condensate (above, manufactured by Orient Chemical Industries), TP-302, TP-415 of quaternary ammonium salt molybdenum complex (above, manufactured by Hodogaya Chemical Co., Ltd.), quaternary ammonium Copy charge PSY VP2038 of salt, copy blue PR of triphenylmethane derivative, copy charge of quaternary ammonium salt NEG VP2036, copy charge NX VP434 (manufactured by Hoechst), LRA-901, LR-147 which is a boron complex (Nippon Carlit), copper phthalocyanine, perylene, quinaclide And azo pigments, and other high molecular compounds having a functional group such as a sulfonic acid group, a carboxyl group, and a quaternary ammonium salt.

  In the present invention, the amount of charge control agent used is determined by the toner production method including the type of binder resin, the presence or absence of additives used as necessary, and the dispersion method, and is uniquely limited. However, it is preferably used in the range of 0.1 to 10 parts by weight with respect to 100 parts by weight of the binder resin. The range of 0.2 to 5 parts by weight is preferable. When the amount exceeds 10 parts by weight, the chargeability of the toner is too high, the effect of the main charge control agent is reduced, the electrostatic attractive force with the developing roller is increased, the flowability of the developer is reduced, and the image density is reduced. Incurs a decline. These charge control agents and mold release agents can be melt-kneaded together with the masterbatch and resin, and of course, they may be added when dissolved and dispersed in an organic solvent.

As the external additive for assisting the fluidity, developability and chargeability of the colorant-containing toner particles obtained in the present invention, inorganic fine particles can be preferably used. The primary particle diameter of the inorganic fine particles is preferably 5 mμ to 2 μm, and particularly preferably 5 mμ to 500 mμ. Moreover, it is preferable that the specific surface area by BET method is 20-500 m < ² > / g. The proportion of the inorganic fine particles used is preferably 0.01 to 5% by weight of the toner, and particularly preferably 0.01 to 2.0% by weight. Specific examples of the inorganic fine particles include, for example, silica, alumina, titanium oxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate, zinc oxide, tin oxide, quartz sand, clay, mica, wollastonite, diatomaceous earth. Examples include soil, chromium oxide, cerium oxide, bengara, antimony trioxide, magnesium oxide, zirconium oxide, barium sulfate, barium carbonate, calcium carbonate, silicon carbide, and silicon nitride.

  In addition, polymer-based fine particles can be used. Examples of such materials include polystyrene obtained by soap-free emulsion polymerization, suspension polymerization, and dispersion polymerization, methacrylic acid ester and acrylic acid ester copolymers, polycondensation systems such as silicone, benzoguanamine, and nylon, and thermosetting resins. Examples include polymer particles.

  Such an external additive can be surface-treated to increase hydrophobicity and prevent deterioration of its flow characteristics and charging characteristics even under high humidity. Preferred examples of the surface treatment agent include silane coupling agents, silylating agents, silane coupling agents having a fluorinated alkyl group, organic titanate coupling agents, aluminum coupling agents, silicone oils, and modified silicone oils. Can be mentioned.

  Examples of the cleaning performance improver for removing the developer after transfer remaining on the photoreceptor or the primary transfer medium include, for example, fatty acid metal salts such as zinc stearate, calcium stearate, and stearic acid, such as polymethyl methacrylate fine particles, polystyrene fine particles Examples thereof include polymer fine particles produced by soap-free emulsion polymerization. The polymer fine particles preferably have a relatively narrow particle size distribution and a volume average particle size of 0.01 to 1 μm.

  Next, the method for producing the toner of the present invention will be described in detail.

  To produce the toner of the present invention, first, in the oily dispersion preparation step, the isocyanate group-containing polyester prepolymer A is dissolved in the organic solvent, the colorant is dispersed, and the release agent is dissolved or dispersed. An oily dispersion is prepared.

  In order to finely pulverize and uniformly disperse the colorant contained therein, the oil-based dispersion liquid is pulverized using a wet pulverizer in a wet pulverization step. In this case, the pulverization time is about 30 to 120 minutes.

  Next, the oily dispersion obtained as described above is dispersed (emulsified) in an aqueous medium in the presence of inorganic fine particles and / or polymer fine particles in the dispersion (emulsification) step to obtain an oil-in-water type. In addition to forming a dispersion (emulsion) and reacting the isocyanate group-containing polyester prepolymer A contained in the dispersion with amine B in the reaction step, a urea-modified polyester resin C having a urea bond is obtained. Generate.

  As the organic solvent, a solvent in which a polyester resin is dissolved and insoluble in water, hardly soluble or slightly soluble is used. The boiling point is usually 60 to 150 ° C, preferably 70 to 120 ° C. As such a thing, ethyl acetate, methyl ethyl ketone, etc. are mentioned, for example.

  In the present invention, it is preferable to use the masterbatch colorant particles described above as the colorant, whereby the colorant can be uniformly dispersed efficiently.

  In the present invention, it is preferable to dissolve polyester-based resin D that is non-reactive with amines as an auxiliary component in the organic solvent. The polyester resin D can also be dispersed in an aqueous medium.

  In the present invention, when the oil dispersion is dispersed in an aqueous medium, the dispersion device is not particularly limited, but known low speed shearing method, high speed shearing method, friction method, high pressure jet method, ultrasonic wave, etc. Can be applied. In order to make the particle diameter of the dispersed particles 2 to 20 μm, the high speed shearing type is preferable. When a high-speed shearing disperser is used, the rotational speed is not particularly limited, but is usually 1000 to 30000 rpm, preferably 5000 to 20000 rpm. The dispersion time is not particularly limited, but in the case of a batch method, it is usually 0.1 to 5 minutes. The temperature during dispersion is usually 0 to 150 ° C. (under pressure), preferably 40 to 98 ° C. Higher temperatures are preferred in that the dispersion has a low viscosity and is easy to disperse.

  The amount of aqueous medium used is usually 50 to 2000 parts by weight, preferably 100 to 1000 parts by weight, based on 100 parts of toner solids such as prepolymer A, colorant, release agent and polyester resin D contained in the oil dispersion. Part. If the amount is less than 50 parts by weight, the toner solids are not well dispersed, and toner particles having a predetermined particle diameter cannot be obtained. If it exceeds 2000 parts by weight, it is not economical. Moreover, a dispersing agent can also be used as needed. It is preferable to use a dispersant because the particle size distribution becomes sharp and the dispersion is stable.

  The time until the wet-pulverized oily liquid is dispersed in the aqueous medium after the treatment is preferably as short as possible.

  As the aqueous medium used in the present invention, water alone may be used, but a solvent miscible with water may be used in combination. Examples of the miscible solvent include alcohol (methanol, isopropanol, ethylene glycol, etc.), dimethylformamide, tetrahydrofuran, cellosolves (methylcellosolve, etc.), lower ketones (acetone, methyl ethyl ketone, etc.) and the like.

  In order to emulsify and disperse the oily phase containing the solid toner in a liquid (aqueous medium) containing water, various surfactants (emulsifiers) can be used as the dispersant. Anionic surfactants such as alkylbenzene sulfonates, α-olefin sulfonates, phosphate esters, alkylamine salts, aminoalcohol fatty acid derivatives, polyamine fatty acid derivatives, amine salt types such as imidazoline, and alkyltrimethylammonium Non-cationic surfactants such as salts, dialkyldimethylammonium salts, alkyldimethylbenzylammonium salts, pyridinium salts, alkylisoquinolinium salts, benzethonium chloride, fatty acid amide derivatives, polyhydric alcohol derivatives, etc. Ionic surfactants such as alanine Dodecyldi (aminoethyl) glycine, di (octyl aminoethyl) glycine and N- alkyl -N, amphoteric surfactants such as N- dimethyl ammonium betaine.

  In the present invention, the effect can be obtained in a very small amount by using a surfactant having a fluoroalkyl group. Preferred anionic surfactants having a fluoroalkyl group include fluoroalkyl carboxylic acids having 2 to 10 carbon atoms and metal salts thereof, disodium perfluorooctanesulfonyl glutamate, 3- [omega-fluoroalkyl (C6-C11 ) Oxy] -1-alkyl (C3-C4) sodium sulfonate, 3- [omega-fluoroalkanoyl (C6-C8) -N-ethylamino] -1-propanesulfonic acid sodium, fluoroalkyl (C11-C20) carvone Acids and metal salts, perfluoroalkylcarboxylic acids (C7 to C13) and metal salts thereof, perfluoroalkyl (C4 to C12) sulfonic acids and metal salts thereof, perfluorooctanesulfonic acid diethanolamide, N-propyl-N- ( 2-hydroxyethyl) -Fluorooctanesulfonamide, perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salt, perfluoroalkyl (C6-C10) -N-ethylsulfonylglycine salt, monoperfluoroalkyl (C6-C16) ethyl phosphate, etc. Is mentioned.

  Product names include Surflon S-111, S-112, S-113 (Asahi Glass Co., Ltd.), Florard FC-93, FC-95, FC-98, FC-129 (Sumitomo 3M Co., Ltd.), Unidyne DS-101. , DS-102 (manufactured by Taikin Kogyo Co., Ltd.), Megafac F-110, F-120, F-113, F-191, F-812, F-833 (Dainippon Ink Co., Ltd.), Xtop EF- 102, 103, 104, 105, 112, 123A, 123B, 306A, 501, 201, 204 (manufactured by Tochem Products), and Fagento F-100, F150 (manufactured by Neos).

  Examples of cationic surfactants include aliphatic primary, secondary or secondary amine acids having a fluoroalkyl group, aliphatic quaternary ammonium salts such as perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salt, benza Luconium salt, benzethonium chloride, pyridinium salt, imidazolinium salt, trade names include Surflon S-121 (manufactured by Asahi Glass), Florard FC-135 (manufactured by Sumitomo 3M), Unidyne DS-202 (manufactured by Daikin Industries) Megafac F-150, F-824 (manufactured by Dainippon Ink, Inc.), Xtop EF-132 (manufactured by Tochem Products), and Footgent F-300 (manufactured by Neos).

  As the inorganic fine particles to be present in the aqueous medium, various conventionally known inorganic compounds that are insoluble or hardly soluble in water are used. Examples of such materials include tricalcium phosphate, calcium carbonate, titanium oxide, colloidal silica, and hydroxyapatite.

  As the polymer fine particles to be present in the aqueous medium, various conventionally known fine particles that are insoluble or hardly soluble in water are used. Examples of such materials include fine particles of hydrophobic polymers such as hydrocarbon resins, fluorine-containing resins, and silicone resins.

  The particle size of the fine particles is usually smaller than the particle size of the toner, and the value of the particle size ratio [volume average particle size of fine particles] / [volume average particle size of toner] is 0 from the viewpoint of particle size uniformity. The range is preferably 0.001 to 0.3. If the particle size ratio is larger than 0.3, fine particles are not efficiently adsorbed on the surface of the toner, so that the particle size distribution of the obtained toner tends to be wide.

  The volume average particle size of the fine particles can be appropriately adjusted within the above range of the particle size ratio so as to obtain a particle size suitable for obtaining a toner having a desired particle size. For example, when it is desired to obtain a toner having a volume average particle diameter of 5 μm, it is preferably 0.0025 to 1.5 μm, particularly preferably in the range of 0.005 to 1.0 μm, and preferably when a toner of 10 μm is obtained. Is 0.005 to 3 μm, particularly preferably 0.05 to 2 μm.

  In the present invention, various hydrophilic polymer substances that form a polymeric protective colloid in the aqueous medium can be present as a dispersion stabilizer in the aqueous medium. In such a polymer substance, the monomer components constituting it can be shown as follows.

  Unsaturated carboxylic acids such as acrylic acid, methacrylic acid, α-cyanoacrylic acid, α-cyanomethacrylic acid, itaconic acid, crotonic acid, fumaric acid, maleic acid or maleic anhydride; β-hydroxyethyl acrylate, methacrylic acid β -Hydroxyethyl, β-hydroxypropyl acrylate, β-hydroxypropyl methacrylate, γ-hydroxypropyl acrylate, γ-hydroxypropyl methacrylate, 3-chloro-2-hydroxypropyl acrylate, 3-chloro-methacrylate 2-hydroxypropyl, diethylene glycol monoacrylate, diethylene glycol monomethacrylate, glycerol monoacrylate, unsaturated carboxylic ester of glycerol monomethacrylate; N-methylolacrylamide , Unsaturated carboxylic acid amides such as N-methylol methacrylamide; vinyl ethers such as vinyl methyl ether, vinyl ethyl ether, vinyl propyl ether, carboxylic acid vinyl esters such as pinyl acetate, pinyl propionate, vinyl butyrate; acrylamide, methacrylamide, Diacetone acrylamide or methylol compounds thereof; acid chlorides such as acrylic acid chloride and methacrylic acid chloride; vinyl monomers having a nitrogen atom such as pinylviridine, vinylpyrrolidone, vinylimidazole, ethyleneimine, or a heterocyclic ring thereof.

  Other polymer materials that can be preferably used in the present invention include polyoxyethylene, polyoxypropylene, polyoxyethylene alkylamine, polyoxypropylene alkylamine, polyoxyethylene alkylamide, polyoxypropylene alkylamide, polyoxyethylene Examples thereof include polyoxyethylenes such as ethylene nonyl phenyl ether, polyoxyethylene lauryl phenyl ether, polyoxyethylene stearyl phenyl ester, and polyoxyethylene nonyl phenyl ester, and celluloses such as methyl cellulose, hydroxyethyl cellulose, and hydroxypropyl cellulose.

  In the present invention, in order to remove the liquid medium contained in the emulsified dispersion obtained after the polyaddition reaction of prepolymer A and amine B, in the liquid medium removing step, the entire system is gradually heated. A method including a step of evaporating and removing the organic solvent can be employed. The circularity of the toner can be controlled by the strength of the liquid agitation before the removal of the organic solvent and the removal time of the organic solvent. By slowly removing the solvent, the shape becomes 0.980 or more when expressed in a sphericity, and by removing the solvent in a short time with strong stirring, the shape becomes irregular or indeterminate, and the shape is expressed as 0.900. ~ 0.950. By controlling the degree of circularity, the emulsion after being emulsified and dispersed in an aqueous medium and further reacted is carried out in the liquid removal medium while stirring with a strong stirring force at a temperature of 30 to 50 ° C. in the liquid removal medium. And shape control in the range of 0.850 to 0.990 is possible. This is thought to be due to volumetric shrinkage caused by abrupt removal of an organic solvent such as ethyl acetate contained in the granulation.

  The liquid medium can be removed by spraying the emulsified dispersion liquid in a dry atmosphere to completely remove the organic solvent to form toner fine particles, and a method of evaporating and removing the aqueous dispersant. . The dry atmosphere in which the emulsified dispersion is sprayed includes air, nitrogen, carbon dioxide, combustion gas, etc. heated gas, preferably various air streams heated to a temperature higher than the boiling point of the highest boiling liquid medium used. Used. High-quality toner can be obtained by short-time processing such as spray dryer, belt dryer and rotary kiln.

  The time until the dispersion after the reaction is desolvated after the reaction is preferably a short time, but is usually within 25 hours.

  In the case where an acid such as calcium phosphate salt or an alkali-soluble material is used as the inorganic fine particles, the toner particles are dissolved by a method such as washing with water after dissolving the inorganic fine particles such as calcium phosphate with an acid such as hydrochloric acid. Inorganic fine particles can be removed from. In addition, it can also be removed by enzymatic degradation.

  When a dispersant is used, the dispersant may remain on the surface of the toner particles. However, it is preferable from the charged surface of the toner that the dispersant is washed and removed after the reaction between the prepolymer A and the amine B.

  Furthermore, in order to lower the viscosity of the dispersion after the reaction, a solvent in which the prepolymer or the urea-modified polyester is soluble can be added to the aqueous medium. The use of a solvent is preferable in that the particle size distribution becomes sharp. The solvent is preferably volatile with a boiling point of less than 100 ° C. from the viewpoint of easy removal. Examples of the solvent include toluene, xylene, benzene, carbon tetrachloride, methylene chloride, 1,2-dichloroethane, 1,1,2-trichloroethane, trichloroethylene, chloroform, monochlorobenzene, dichloroethylidene, methyl acetate, ethyl acetate, Methyl ethyl ketone, methyl isobutyl ketone and the like can be used alone or in combination of two or more. In particular, aromatic solvents such as toluene and xylene and halogenated hydrocarbons such as methylene chloride, 1,2-dichloroethane, chloroform, and carbon tetrachloride are preferable. The usage-amount of the solvent with respect to 100 parts of prepolymers (A) is 0-300 parts normally, Preferably it is 0-100 parts, More preferably, it is 25-70 parts. When a solvent is used, after the reaction of prepolymer A and amine B, the solvent is removed by heating under normal pressure or reduced pressure.

  The reaction time of the prepolymer A and the amine B is selected depending on the reactivity depending on the combination of the isocyanate group structure of the prepolymer (A) and the amine (B), but usually 10 minutes to 40 hours, preferably 2 to 24 It's time. The reaction temperature is generally 0 to 150 ° C, preferably 40 to 98 ° C. Moreover, a well-known catalyst can be used as needed. Specific examples include dibutyltin laurate and dioctyltin laurate.

  When the particle size distribution of the toner particles in the emulsified dispersion after the reaction of the prepolymer A and the amine B is wide, and the washing and drying processes are performed while maintaining the particle size distribution, the particles are classified into a desired particle size distribution to adjust the particle size distribution. be able to. In the classification operation in this case, the fine particle portion can be removed in the liquid by a cyclone, a decanter, centrifugation, or the like. Of course, the classification operation may be performed after obtaining the powder as a powder after drying. The unnecessary fine particles or coarse particles obtained can be returned to the kneading step and used for the formation of particles. At that time, fine particles or coarse particles may be wet.

  The dispersant used is preferably removed from the obtained dispersion as much as possible, but it is preferable to carry out it simultaneously with the classification operation described above.

  When the dried toner particles are mixed with different types of particles such as release agent fine particles, charge control fine particles, and fluidizing agent fine particles as necessary, mechanical impact force is applied to the mixed powder. Thus, the foreign particles can be immobilized and fused on the surface of the toner particles, and the detachment of the foreign particles from the surface of the resulting composite particles can be prevented.

  Specific means include a method of applying an impact force to the mixture by blades rotating at high speed, a method of injecting and accelerating the mixture in a high-speed air stream, and causing particles or composite particles to collide with an appropriate collision plate, etc. is there. As equipment, Ong mill (manufactured by Hosokawa Micron Co., Ltd.), I-type mill (manufactured by Nippon Pneumatic Co., Ltd.) is modified to reduce the grinding air pressure, hybridization system (manufactured by Nara Machinery Co., Ltd.), kryptron system (Made by Kawasaki Heavy Industries, Ltd.), automatic mortar and the like.

When the toner of the present invention is used for a two-component developer, it may be used by mixing with a magnetic carrier. The carrier to toner content ratio in the developer is preferably 1 to 10 parts by weight of toner with respect to 100 parts by weight of carrier. As the magnetic carrier, conventionally known ones such as iron powder, ferrite powder, magnetite powder, magnetic resin carrier having a particle diameter of about 20 to 200 μm can be used. Examples of the coating material include amino resins such as urea-formaldehyde resin, melamine resin, benzoguanamine resin, urea resin, polyamide resin, and epoxy resin. Polyvinyl and polyvinylidene resins such as acrylic resins, polymethyl methacrylate resins, polyacrylonitrile resins, polyvinyl acetate resins, polyvinyl alcohol resins, polyvinyl butyral resins, polystyrene resins and styrene acrylic copolymer resins, Halogenated olefin resins such as vinyl, polyester resins such as polyethylene terephthalate resin and polybutylene terephthalate resin, polycarbonate resins, polyethylene resins, polyvinyl fluoride resins, polyvinylidene fluoride resins, polytrifluoroethylene resins, polyhexafluoro Propylene resin, copolymer of vinylidene fluoride and acrylic monomer, copolymer of vinylidene fluoride and vinyl fluoride, tetrafluoroethylene and vinylidene fluoride And fluoro such as terpolymers of non-fluoride monomers including, and silicone resins. Moreover, you may make conductive powder etc. contain in coating resin as needed. As the conductive powder, metal powder, carbon black, titanium oxide, tin oxide, zinc oxide or the like can be used. These conductive powders preferably have an average particle diameter of 1 μm or less. When the average particle diameter is larger than 1 μm, it becomes difficult to control electric resistance.
The toner of the present invention can also be used as a one-component magnetic toner that does not use a carrier or a non-magnetic toner.

  EXAMPLES The present invention will be further described below with reference to examples, but the present invention is not limited thereto. Hereinafter, a part shows a weight part. The toner used in each example is shown in Table 1.

Reference example 1
(Production example of polyester for addition)
In a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen introducing tube, 690 parts of bisphenol A ethylene oxide 2-mole adduct and 230 parts of terephthalic acid were subjected to polycondensation at 210 ° C. for 10 hours under normal pressure, and then reduced in pressure to 10 to 15 mmHg. And then cooled to 160 ° C., 18 parts of phthalic anhydride was added thereto and reacted for 2 hours to obtain unmodified polyester (a) (weight average molecular weight Mw: 85000).

(Prepolymer production example)
In a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen introduction tube, 800 parts of bisphenol A ethylene oxide 2-mol adduct, 160 parts of isophthalic acid, 60 parts of terephthalic acid, and 2 parts of dibutyltin oxide were placed at normal pressure. The mixture was reacted at 8 ° C. for 8 hours, further reacted for 5 hours while dehydrating at a reduced pressure of 10 to 15 mmHg, cooled to 160 ° C., 32 parts of phthalic anhydride was added thereto, and reacted for 2 hours. Next, the mixture was cooled to 80 ° C. and reacted with 170 parts of isophorone diisocyanate in ethyl acetate for 2 hours to obtain an isocyanate group-containing prepolymer (1) (Mw: 35000).

(Production example of ketimine compound)
In a reaction vessel equipped with a stir bar and a thermometer, 30 parts of isophoronediamine and 70 parts of methyl ethyl ketone were charged and reacted at 50 ° C. for 5 hours to obtain a ketimine compound (1).

(Example of toner production)
In a beaker, 14.3 parts of the prepolymer (1), 55 parts of polyester (a), and 78.6 parts of ethyl acetate were placed and stirred to dissolve. Next, 10 parts of rice WAX (melting point 83 ° C.) as a release agent and 4 parts of copper phthalocyanine blue pigment were added, stirred at 12000 rpm for 5 minutes at 40 ° C. with a TK homomixer, and then at 20 ° C. for 30 minutes with a bead mill. Grinded. This is designated as toner material oil dispersion (1).

  In a beaker, 306 parts of ion-exchanged water, 265 parts of a 10% tricalcium phosphate suspension, and 0.2 part of sodium dodecylbenzenesulfonate were added, and this aqueous dispersion (1) was stirred with a TK homomixer at 12000 rpm. ) And 2.7 parts of the toner material oil dispersion (1) and ketimine compound (1) were added and allowed to undergo urea reaction while stirring was continued.

  After removing the organic solvent from the dispersion (viscosity: 3500 mP · s) under reduced pressure at a temperature of 50 ° C. or less within 1.0 hour under reduced pressure, it is filtered, washed and dried, then air-classified, Toner base particles (1) were obtained.

  Next, 100 parts of the obtained base particles (1) and 0.25 part of a charge control agent (Bontron E-84 manufactured by Orient Chemical Co., Ltd.) were charged into a Q-type mixer (manufactured by Mitsui Mining Co., Ltd.), and the peripheral speed of the turbine blades Was set to 50 m / sec and mixed. In this case, the mixing operation was performed for 2 minutes, 5 cycles of 1 minute pause, and the total treatment time was 10 minutes.

  Further, 0.5 part of hydrophobic silica (H2000, manufactured by Clariant Japan) was added and mixed. In this case, the mixing operation was performed for 5 cycles of 30 seconds of mixing for 1 minute with a peripheral speed of 15 m / sec.

Thus, cyan toner (1) was obtained. The average dispersion particle diameter of the pigment-based colorant was 0.4 μm, and the number% of the particle diameter of 0.7 μm or more was 3.5%. Properties and evaluation results of this toner are shown in Tables 1 and 2.

Example 2
(Preparation of magenta master batch particles)
Water 600 parts Pigment Red 57 Water-containing cake (solid content 50%) 200 parts is thoroughly stirred with a flasher. here,
Add 1200 parts of polyester resin (acid value; 3, hydroxyl value; 25, Mn; 3500, Mw / Mn; 4.0, Tg; 60 ° C.), knead at 150 ° C. for 30 minutes, and then add 1000 parts of xylene and further 1 After kneading for a time, water and xylene were removed, rolled and cooled, pulverized with a pulverizer, and further passed with a three-roll mill to obtain a magenta master batch pigment (MB1-M) (average particle size of about 0.2 μm). .

(Prepolymer production example)
856 parts of bisphenol A ethylene oxide 2-mole adduct, 200 parts of isophthalic acid, 20 parts of terephthalic acid, and 4 parts of dibutyltin oxide are placed in a reaction vessel equipped with a cooling pipe, a stirrer and a nitrogen introduction pipe. The mixture was reacted at 6 ° C. for 6 hours and further reacted for 5 hours while dehydrating at a reduced pressure of 50 to 100 mmHg, then cooled to 160 ° C., 18 parts of phthalic anhydride was added thereto, and the mixture was reacted for 2 hours. Next, the mixture was cooled to 80 ° C. and reacted with 170 parts of isophorone diisocyanate in ethyl acetate for 2 hours to obtain an isocyanate group-containing prepolymer (2) (Mw: 25000).

(Example of toner production)
In a beaker, 15.4 parts of the prepolymer (1), 50 parts of polyester (a) and 95.2 parts of ethyl acetate were stirred and dissolved. Next, 10 parts of carnauba wax (molecular weight 1800, acid value 2.5, needle penetration degree 1.5 mm / 40 ° C.) and 10 parts of master batch particles of Example 2 were added, and 10000 rpm with a TK homomixer at 85 ° C. After that, the mixture was wet pulverized by a bead mill in the same manner as in Reference Example 1 to obtain a toner material oil dispersion (2).

Subsequently, spherical base toner particles (2) were obtained in the same manner as in Reference Example 1 except that the aqueous dispersion (2) obtained in the same manner as in Reference Example 1 was used.

Next, a toner (2) was obtained in the same manner as in Reference Example 1, except that Orient-made Bontron E-84 was changed to E-89 as the charge control material. The average dispersion particle diameter of the pigment-based colorant in the toner was 0.25 μm, and the number% of the particle diameter of 0.5 μm or more was 1.0%. Properties and evaluation results of the toner are shown in Tables 1 and 2.

Example 3
(Prepolymer production example)
755 parts of bisphenol A ethylene oxide 2-mole adduct, 195 parts of isophthalic acid, 15 parts of terephthalic acid, and 4 parts of dibutyltin oxide are placed in a reaction vessel equipped with a cooling pipe, a stirrer and a nitrogen introduction pipe. The mixture was reacted at 8 ° C. for 8 hours, further reacted for 5 hours while dehydrating at a reduced pressure of 50 to 100 mmHg, cooled to 160 ° C., 10 parts of phthalic anhydride was added thereto, and reacted for 2 hours. Next, the mixture was cooled to 80 ° C. and reacted with 170 parts of isophorone diisocyanate in ethyl acetate for 2 hours to obtain an isocyanate group-containing prepolymer (3) (Mw: 25000).

(Example of toner production)
In a beaker, 15.4 parts of the prepolymer (3), 50 parts of polyester (a) and 95.2 parts of ethyl acetate were stirred and dissolved. Next, 10 parts of carnauba wax (molecular weight 1800, acid value 2.5, needle penetration degree 1.5 mm / 40 ° C.) and 15 parts of master batch particles of Example 2 were added, and 14,000 rpm with a TK homomixer at 85 ° C. The mixture was stirred and dispersed uniformly, and then wet milled at 15 ° C. for 60 minutes in a bead mill. This is designated as toner material oil dispersion (3).

  In a beaker, 465 parts of ion-exchanged water, 245 parts of a 10% sodium carbonate suspension, and 0.4 part of sodium dodecylbenzenesulfonate were added and stirred to obtain an aqueous dispersion (3). Next, the temperature of the dispersion (3) was raised to 40 ° C., and the toner material oil dispersion (4) was added and stirred for 10 minutes while stirring at 12000 rpm with a TK homomixer, and then the ketimine compound (1) 2 7 parts were added and reacted. Thereafter, the solvent was removed within 1 hour at 40 ° C., and then filtered, washed and dried in the same manner as in Example 2 to obtain spherical base particles (3).

Next, a toner (3) was obtained in the same manner as in Reference Example 1 except that this base toner particle was used. The average dispersion particle size of the pigment-based colorant in this toner was 0.15 μm, and the number% of the particle size of 0.5 μm or more was 3.0%. Properties and evaluation results of the toner are shown in Tables 1 and 2.

Comparative Example 1
(Toner binder synthesis)
A comparative toner binder (11) was obtained by polycondensation of 354 parts of bisphenol A ethylene oxide 2-mole adduct and 166 parts of isophthalic acid using 2 parts of dibutyltin oxide as a catalyst. The comparative toner binder (11) had a Tg of 57 ° C.

(Create toner)
In a beaker, 100 parts of the comparative toner binder (1), 200 parts of ethyl acetate solution, 4 parts of copper phthalocyanine blue pigment, and 5 parts of rice wax used in Reference Example 1 were placed at 12000 rpm with a TK homomixer at 50 ° C. And a comparative dispersion liquid (11) was obtained. A comparative toner (11) having a volume average particle diameter of 6 μm was obtained in the same manner as in Reference Example 1 except that this dispersion liquid (11) was used. The average dispersion particle size of the pigment-based colorant in the toner was 0.70 μm, and the number percentage of the particle size of 0.7 μm or more was 35%. Properties and evaluation results of the toner are shown in Tables 1 and 2.

Comparative Example 2
(Toner binder synthesis)
343 parts of bisphenol A ethylene oxide 2-mole adduct, 166 parts of isophthalic acid, and 2 parts of dibutyltin oxide are placed in a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen introduction tube, and reacted at 230 ° C for 8 hours at normal pressure. Further, after reacting at a reduced pressure of 10 to 15 mmHg for 5 hours, cooling to 80 ° C., adding 14 parts of toluene diisocyanate in toluene, reacting at 110 ° C. for 5 hours, and then removing the solvent, urethane having a peak top molecular weight of 7000 A modified polyester was obtained. Bisphenol A ethylene oxide 2-mol adduct 363 parts and isophthalic acid 166 parts were polycondensed in the same manner as in Reference Example 1 to obtain an unmodified polyester having a peak molecular weight of 3800 and an acid value of 7. 350 parts of the urethane-modified polyester and 650 parts of the unmodified polyester were dissolved in toluene and mixed, and then the solvent was removed to obtain comparative toner binder base particles (12). The comparative toner binder (12) had a Tg of 58 ° C.

(Create toner)
100 parts of comparative toner binder (12), 10 parts of each of the master batch particles and Carnauba Wax used in Example 2 were added, and toner was formed by the following method.

First, after preliminary mixing using a Henschel mixer, the mixture was kneaded with a continuous kneader. Subsequently, the mixture was finely pulverized by a jet pulverizer and then classified by an airflow classifier to obtain toner particles having a volume average particle diameter of 6 μm. Subsequently, 100 parts of toner particles were mixed with 0.5 part of hydrophobic silica and 0.5 part of hydrophobic titanium oxide using a Henschel mixer to obtain a comparative toner (12). The average dispersion particle diameter of the pigment-based colorant in the toner was 0.7 μm, and the number% of the particle diameter of 0.5 μm or more was 15.0%. Properties and evaluation results of the toner are shown in Tables 1 and 2.

(Evaluation methods)
(1) Tg measuring method The measuring method of Tg is outlined. As an apparatus for measuring Tg, a TG-DSC system TAS-100 manufactured by Rigaku Corporation was used.

  First, about 10 mg of a sample is placed in an aluminum sample container, which is placed on a holder unit and set in an electric furnace. First, after heating from room temperature to 150 ° C. at a temperature rising rate of 10 ° C./min, the sample was allowed to stand at 150 ° C. for 10 min, the sample was cooled to room temperature and left for 10 min, and the temperature rising rate was again increased to 150 ° C. under a nitrogen atmosphere. DSC measurement was performed by heating at min. Tg was calculated from the contact point between the tangent line of the endothermic curve near the Tg and the base line using the analysis system in the TAS-100 system.

(2) Acid value measurement method According to the method specified in JISK0070. However, if the sample does not dissolve, dioxane or tetrahydrofuran is used as the solvent.

(3) Powder flowability The bulk density (g / ml) was measured using a powder tester manufactured by Hosokawa Micron. The toner with better fluidity has a higher bulk density. The following four levels were evaluated.

×: Less than 0.25 Δ: 0.25 to 0.30
○: 0.30 to 0.35
: 0.35 or more

(4) Minimum fixing temperature Ricoh type 6200 was used by using an apparatus in which the fixing unit of a copying machine using a Teflon (registered trademark) roller as a fixing roller [Copier MF-200 manufactured by Ricoh Co., Ltd.] was modified. Paper was set and a copy test was conducted. The fixing roll temperature at which the residual ratio of the image density after rubbing the fixed image with a pad becomes 70% or more was determined as the minimum fixing temperature.

(5) Hot offset generation temperature (HOT)
Fixing was evaluated in the same manner as the above-described minimum fixing temperature, and the presence or absence of hot offset on the fixed image was visually evaluated. The fixing roll temperature at which hot offset occurred was defined as the hot offset occurrence temperature.

(6) Gloss expression temperature (GLOSS)
The fixing was evaluated using a fixing device of a commercially available color copying machine (PRETER 550; manufactured by Ricoh). The fixing roll temperature at which the 60 ° gloss of the fixed image is 10% or more was defined as the gloss development temperature.

(7) Haze degree:
Direct reading haze computer (HGM-2DP type).

Claims (14)

An oily dispersion in which at least a polyester-based prepolymer containing an isocyanate group is dissolved in an organic solvent, a pigment-based colorant added as masterbatch colorant particles is dispersed, and a release agent is dissolved or dispersed. obtaining an aqueous dispersion by dispersing in an aqueous medium in the presence of inorganic particles and / or polymer fine particles, the prepolymer is reacted with a monoamine having a polyamine and / or an active hydrogen-containing group in the aqueous dispersion toner for electrophotography comprising the step of obtaining an electrophotographic toner by removing the liquid medium from the aqueous dispersion containing the process as well as the urea-modified polyester resin that form a urea-modified polyester resin having a urea group by Rukoto A manufacturing method of
Pigment colorant dispersed in the electrophotographic toner is a number average diameter of 0.3 [mu] m or less state, and are the ratio of particles diameter is 0.7μm or 5% by number or less, A method for producing an electrophotographic toner, wherein the proportion of particles having a particle diameter of 0.5 μm or more is 10% by number or less . The oil dispersions, method of manufacturing toner for electrophotography according to claim 1, characterized in that is obtained by further wet grinding.   The electrophotographic toner has a weight average particle size of 3.0 to 7.0 μm, and a ratio of the weight average particle size to the number average particle size of 1.00 to 1.20. Item 3. A method for producing an electrophotographic toner according to Item 1 or 2.   The method for producing an electrophotographic toner according to any one of claims 1 to 3, wherein the electrophotographic toner has a circularity of 0.900 to 0.960.   The tetrahydrofuran-soluble component of the polyester resin contained in the electrophotographic toner has a main peak in a region having a molecular weight of 2500 to 10,000 and a number average molecular weight of 2500 to 50,000. The method for producing an electrophotographic toner according to any one of 1 to 4.   6. The polyester resin contained in the electrophotographic toner has a glass transition point of 40 to 65 ° C. and an acid value of 1 to 30 mgKOH / g. A process for producing an electrophotographic toner as described in 1 above.   The electron according to any one of claims 1 to 6, wherein the oil-based dispersion is dissolved with a polyamine and / or a monoamine having an active hydrogen-containing group and a non-reactive polyester-based resin. A method for producing a photographic toner.   A developer comprising the toner obtained by the toner production method according to claim 1 and a carrier.   A toner container filled with toner obtained by the method for producing toner according to claim 1.   A developer container filled with the developer according to claim 8.   A developing method comprising developing with the toner obtained by the toner manufacturing method according to claim 1.   A developing device that performs development using the toner obtained by the toner manufacturing method according to claim 1.   A developing device that performs development using the toner filled in the toner container according to claim 9.   A developing device that performs development using the developer filled in the developer container according to claim 10.