JP3977371B2 - Toner and method and apparatus for forming an image using the toner - Google Patents

Description

  The present invention relates to a toner used as a developer for developing an electrostatic image in electrophotography, electrostatic recording, electrostatic printing and the like, and an electrophotographic developing apparatus using the toner. More specifically, the present invention relates to an electrophotographic toner used in a copying machine, a laser printer, a plain paper fax machine, and the like using a direct or indirect electrophotographic developing system, and an image forming method.

  In recent years, the strong demand for higher image quality from the market has spurred the development of an electrophotographic apparatus suitable for it and a toner developer used therefor. As a toner corresponding to high image quality, it is essential that the toner has a uniform particle size. When the toner particle size is uniform and the particle size distribution becomes sharp, the behavior of individual toner particles during development is aligned, and the reproducibility of minute dots is remarkably improved.

  However, a toner having a smaller particle size and a uniform particle size is more difficult to clean than before. Particularly in blade cleaning, it is impossible to stably clean toner having a uniform and small particle diameter. Under such circumstances, various methods for improving the cleaning property by devising the toner have been proposed. One of them is a method of changing the toner from a spherical shape to a different shape. By changing the shape of the toner, the powder fluidity of the toner is lowered, and it is easy to stop by blade cleaning. However, if the degree of toner irregularity is too large, the behavior of the toner becomes unstable during development and the like, and the fine dot reproducibility deteriorates.

  As described above, by changing the shape of the toner, the reliability of the toner for cleaning is certainly improved, but on the other hand, there is a problem in terms of fixing. In other words, when the shape of the toner is made irregular, the toner filling density in the toner layer on the transfer material before fixing becomes small, the thermal conductivity in the toner layer becomes slow during fixing, and the low-temperature fixability deteriorates. Resulting in. In particular, when the pressure at the time of fixing is smaller than the conventional pressure, the thermal conductivity is further deteriorated and the low-temperature fixing is hindered.

  Japanese Patent Application Laid-Open No. 11-133665 proposes a toner made of polyester having a Wadell practical sphericity of 0.90 to 1.00. However, since the toner is substantially spherical, the toner cleaning property described above is improved. The problem has not been solved.

  In addition to suspension polymerization, there are emulsion polymerization methods and dissolution suspension methods that are relatively easy to modify, but also in the emulsion polymerization method, complete removal of styrene monomers and removal of emulsifiers and dispersants are possible. It is difficult, and the problem with toners is becoming increasingly greater as environmental problems have become particularly close. Also, in the toner shape, the contamination of the photoreceptor due to the toner is caused by the fact that the concave portion of the silica added as a fluidizing agent is weakly adhered to the concave portion and the silica moves to the concave portion during use. And the problem of toner adhesion to the fixing roller are likely to occur. In addition, the dissolution suspension method has the advantage that a polyester resin that can be fixed at low temperature can be used, but in order to achieve oil-less fixing, the polymer and color are controlled during production and control of the polymer to widen the mold release width. Since the high molecular weight component is added in the step of dissolving or dispersing the agent in the solvent, the viscosity of the liquid rises and productivity problems are likely to occur. And those problems are not solved yet. In particular, in the solution suspension method, in Japanese Patent Laid-Open No. 9-15903, the toner surface shape is made spherical and uneven to improve the cleaning. A high-molecular weight design for ensuring stability and further ensuring basic durability and releasability has not been achieved, and a toner of satisfactory quality has not been obtained.

The subject of this invention is as follows.
(1) Toner and image forming apparatus capable of obtaining a high-quality image with excellent fine dot reproducibility are provided.
(2) To provide a toner and an image forming apparatus that can obtain high reliability especially in cleaning.
(3) To provide a toner and an image forming apparatus excellent in low-temperature fixability.
(4) A toner and an image forming apparatus capable of achieving the same problems (1) to (3) are provided.
(5) To provide a dry toner and an image forming apparatus which are excellent in transfer efficiency and which can obtain a high quality image with little transfer residual toner.
(6) To provide an oilless dry toner having both charging stability and low-temperature fixability.
(7) To provide a novel toner that consumes less power and has both high transferability and OHP transparency required for color images at a high level.

  The present inventors have completed the present invention to solve the above-described problems.

That is, according to the present invention, the following toner and image forming method and apparatus are provided.
(1) A toner comprising at least a binder resin and a colorant, which is granulated in an aqueous medium, and a ratio Dv / Dn between the volume average particle diameter (Dv) and the number average particle diameter (Dn) of the toner 1.00 to 1.30, the main components of the binder resin are a modified polyester resin and an unmodified polyester resin, and the weight ratio of the modified polyester resin to the unmodified polyester resin (modified / unmodified) ) is 5/95 to 80/20, the toner shape factor SF-1 of the toner is Ri 150-180 der, which and shape factor SF-2 of the toner is characterized 100-130 der Rukoto .
(2) The toner according to (1) above, wherein Dv / Dn of the toner is 1.00 to 1.20 .
(3 ) The toner according to (1) or ( 2), wherein the volume average particle diameter Dv is 3.0 to 7.0 μm .
(4 ) A modified polyester resin capable of reacting with active hydrogen, a colorant and a release agent are dispersed in an aqueous medium in the presence of a dispersant, and the resulting dispersion is reacted with a crosslinking agent and / or an extender. The toner according to any one of (1) to ( 3 ), wherein the toner is obtained by removing a solvent from the dispersion liquid obtained.
( 5 ) A dispersion obtained by dispersing a toner composition comprising a modified polyester resin capable of reacting with active hydrogen in an organic solvent, a colorant and a release agent in the presence of a dispersant is dispersed in an aqueous medium. The toner according to ( 4 ), wherein the toner is obtained by reacting with a crosslinking agent and / or an extender to remove the solvent from the obtained dispersion.
( 6 ) A dispersion obtained by dispersing a toner composition comprising a modified polyester resin capable of reacting with active hydrogen, a colorant and a release agent in an organic solvent in the presence of a dispersant is dispersed in an aqueous medium. It was obtained by reacting with a cross-linking agent and / or an extender and stirring the resulting dispersion in a stirring tank free from baffles and protrusions, and then removing the solvent from the dispersion at 10 to 50 ° C. The toner according to ( 5 ), wherein the toner is a toner.
( 7 ) In the molecular weight distribution of the tetrahydrofuran-soluble resin in the toner, the main peak is present in the region of the molecular weight of 2500 to 10,000, and the tetrahydrofuran-insoluble resin is contained in an amount of 1 to 25%. The toner according to any one of ( 6 ) to ( 6 ).
( 8 ) The toner according to ( 7 ) above, wherein a component having a molecular weight of less than 2500 is 0.1 to 5.0% in the molecular weight distribution of the tetrohydrofuran-soluble resin in the toner.
( 9 ) The glass transition point of the modified polyester resin in the toner is 40 to 70 ° C., and the acid value is 1 to 30 mgKOH / g, in any one of the above ( 4 ) to ( 8 ) Toner.
( 10 ) The toner according to any one of (1) to ( 9 ), wherein the toner is used for a two-component developer.
(11) an image forming method and a cleaning step of cleaning with the toner remaining on the transfer process and the toner image bearing member surface after the transfer to be transferred to a transfer material the toner image carried on the toner image bearing member on the blade And an image forming method using the toner according to any one of (1) to ( 10 ).
( 12 ) An image forming apparatus having transfer means for transferring a toner image carried on a toner image carrier to a transfer material, and cleaning means for cleaning toner remaining on the surface of the toner image carrier using a blade after the transfer. And an image forming apparatus using the toner according to any one of (1) to ( 10 ).
( 13 ) An image forming apparatus in which a toner image on a transfer material is fixed by heating and melting by passing between two rollers, and a surface pressure (roller load / contact area) applied between the two rollers. ) Is fixed at 1.5 × 10 ⁵ Pa or less, and the toner according to any one of (1) to ( 10 ) is used.

  The dry toner of the present invention is excellent in low-temperature fixability, has little residual toner in an apparatus using blade cleaning, and gives an image with high image quality and high resolution.

  Next, embodiments of the present invention will be described with reference to the drawings.

  In the toner of the present invention, the ratio (Dv / Dn) of the volume average particle diameter (Dv) to the number average particle diameter (Dn) is 1.00 to 1.30, which is high resolution and high image quality. It is possible to obtain the toner. Furthermore, in the case of a two-component developer, even if a long-term balance of the toner is performed, fluctuations in the particle size of the toner in the developer are reduced, and good and stable developability even with long-term stirring in the developing device. Is possible. If Dv / Dn exceeds 1.30, the variation in particle size of individual toner particles is large, and the behavior of the toner varies during development and the like, and the reproducibility of minute dots is impaired. Therefore, a high-quality image cannot be obtained. More preferably, Dv / Dn is in the range of 1.00 to 1.20, and a better image can be obtained.

  In the toner of the present invention, the volume average particle diameter Dv is preferably 3.0 to 7.0 μm. In general, it is said that the smaller the particle size of the toner, the more advantageous it is to obtain a high-resolution and high-quality image, but it is disadvantageous for transferability and cleaning properties. is there. When the volume average particle diameter is smaller than the above range, in the case of a two-component developer, the toner is fused to the surface of the carrier during a long period of stirring in the developing device, and the charging ability of the carrier is reduced. When it is used, toner filming on the developing roller and toner fusion to a member such as a blade for thinning the toner are likely to occur. In addition, these phenomena are greatly related to the content of fine powder. In particular, when the particle size of 3 μm or less exceeds 10%, it becomes an obstacle to the adhesion to the carrier and the high level of charging stability. Conversely, when the toner particle size is larger than the above range, it becomes difficult to obtain a high-resolution and high-quality image, and the toner particle size when the balance of the toner in the developer is performed. In many cases, fluctuations of It was also clarified that the same applies when the volume average particle diameter / number average particle diameter is larger than 1.30.

  As described above, a toner having a small particle size and a uniform particle size has difficulty in cleaning performance. Therefore, the shape factor SF-1 of the toner is preferably in the range of 140 to 200.

  First, the relationship between toner shape and transferability will be described. When using a full-color copier that transfers images with multi-color development, the amount of toner on the photoconductor increases compared to the case of one-color black toner used in black-and-white copiers. It is difficult to improve transfer efficiency. In addition, when ordinary irregular toner is used, a shearing force or friction between the photosensitive member and the cleaning member, between the intermediate transfer member and the cleaning member, and / or between the photosensitive member and the intermediate transfer member. Due to the force, toner fusing or filming occurs on the surface of the photoreceptor or the intermediate transfer member, and transfer efficiency tends to deteriorate. When generating a full-color image, it is difficult to transfer the four-color toner images uniformly. Furthermore, when an intermediate transfer member is used, problems are likely to occur in terms of color unevenness and color balance, and high-quality full-color images are stabilized. Output is not easy.

  From the viewpoint of the balance between blade cleaning and transfer efficiency, the toner shape factor SF-1 is 140 to 200, preferably 150 to 180, so that both cleaning and transferability can be achieved. Cleaning and transferability are greatly related to the material of the blade and how to apply the blade, and transfer is also different depending on the process conditions. Therefore, the design according to the process can be performed within the range of SF-1. However, if SF-1 falls below 140, cleaning with a blade becomes difficult. On the other hand, when SF-1 exceeds 200, the aforementioned transferability is deteriorated. This phenomenon is caused by the shape of the toner being deformed and the movement of toner during transfer (photosensitive member surface to transfer paper, photosensitive member surface to intermediate transfer belt, first intermediate transfer belt to second intermediate transfer belt, etc.) Since the toner particles are not smooth and the behavior of the toner particles varies, uniform and high transfer efficiency cannot be obtained. In addition, unstable charging and brittleness of particles begin to appear. Furthermore, it becomes a fine phenomenon in the developer, which causes a decrease in the durability of the developer.

  The shape of the toner is preferably a spindle shape with a shape factor SF-1 in the range of 140 to 200. The spindle shape has excellent transferability after the spherical shape because there are few large irregularities on the surface. The cleaning property, which is in a trade-off relationship with the transfer property, is also good, and it can be said that the shape is very balanced.

  In the case of the pulverized toner, the toner is indefinite shape (a shape that is not a specific and well-rounded shape) and the toner has a shape factor SF-1 exceeding 140. However, since the particle size distribution of the toner is generally broad, In order to make Dv / Dn 1.30 or less, this is an inefficient method. When a toner is obtained by a polymerization method, for example, suspension polymerization or emulsion polymerization makes it difficult to make a polyester toner, and it cannot cope with further low-temperature fixing. In a dry toner comprising a toner binder obtained by subjecting an isocyanate group-containing prepolymer to an extension reaction and / or a crosslinking reaction in JP-A Nos. 11-149180 and 2000-292981, and a colorant, the dry toner comprises the prepolymer ( A dry toner characterized by comprising particles formed by elongation reaction and / or cross-linking reaction with amines (B) in an aqueous medium of A) has been proposed, and the toner shape of the present invention is proposed. Therefore, transferability and cleaning performance cannot be achieved at the same time.

  Therefore, in the present invention, in the toner production method using the reaction of the prepolymer (A) and the amines (B), the process conditions for evaporating the solvent from the toner liquid after the reaction are controlled, so that the spindle shape is obtained. It became possible to obtain a toner with less unevenness on the surface. Specifically, a toner having a spindle shape, a shape factor SF-1 of 140 to 200, and an SF-2 of 100 to 130 can be easily obtained. In conventional suspension polymerization and emulsion polymerization, the solvent removal step is different from the case of the present invention, and shape control is difficult.

Hereafter, the measuring method regarding the property of the toner of this invention is shown.
(Toner shape)
In the present invention, SF-1 and SF-2 indicating the shape factor of the toner are conventionally known coefficients. For example, SF-1 is enlarged to 500 times magnification by using FE-SEM (S-800) manufactured by Hitachi. 100 toner images are randomly sampled, and the image information can be obtained by introducing the image information into, for example, an image analysis apparatus (Luzex III) manufactured by Nicole via an interface and performing analysis.

(Toner particle size)
The average particle size and the particle size distribution of the toner are determined by the 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, measurement was performed using a Coulter counter TA-II type connected to an interface (Nichiken Giken) that outputs number distribution and volume distribution and a PC9801 personal computer (manufactured by NEC).

  The measurement method is described below.

  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 a solution prepared by preparing a 1% NaCl aqueous solution 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 treatment with an ultrasonic disperser for about 1 to 3 minutes, and the measurement device is used to measure the volume and number of toner particles or toner using a 100 μm aperture as an aperture. Volume distribution and number distribution are calculated.

  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 volume-based volume average particle diameter (Dv) obtained from the volume distribution according to the present invention and the number average particle diameter (Dn) obtained from the number distribution and the ratio Dv / Dn were obtained.

(Hot offset resistance)
Regarding hot-offset resistance, various studies have been conducted so far to control the molecular weight distribution of the binder resin. In order to achieve both conflicting properties such as low-temperature fixability and hot offset resistance, for example, a binder resin with a wide molecular weight distribution is used, a polymer component having a molecular weight of hundreds of thousands or millions, and a molecular weight of several This is a method of mixing 1,000 to tens of thousands of low-molecular components having at least two molecular weight peaks and separating the functions of the respective components. When the polymer component has a crosslinked structure or is in a gel state, it is more effective for hot offset resistance. However, in a full-color toner that also requires glossiness and transparency, it is not preferable to introduce a large amount of a polymer component. In the toner of the present invention, the polyester can be stretched through a urea bond to increase the molecular weight, so that an appropriate amount of 1% or more of a high molecular weight component effective for hot offset resistance is added while satisfying transparency and glossiness. Thus, it has become possible to achieve hot offset resistance.

(Molecular weight distribution)
The molecular weight distribution of the binder component (resin component) in the toner is measured by the following method. After about 1 g of toner is carefully evaluated in an Erlenmeyer flask, 10 to 20 g of THF (tetrahydrofuran) is added to obtain a THF solution having a binder concentration of 5 to 10%. The column is stabilized in a heat chamber at 40 ° C., and THF as a solvent is allowed to flow through the column at this temperature at a flow rate of 1 ml / min, and 20 μl of the THF sample solution is injected. The molecular weight of the sample is calculated from the relationship between the retention value and the logarithmic value of a calibration curve prepared from a monodisperse polystyrene standard sample. A calibration curve is created using a polystyrene standard sample. As a monodisperse polystyrene standard sample, the thing of the range of molecular weight 2.7 * 10 < ² > -6.2 * 10 < ⁶ > by Tosoh Corporation is used, for example. A refractive index (RI) detector is used as the detector. As the column, for example, TSKgel, G1000H, G2000H, G2500H, G3000H, G4000H, G5000H, G6000H, G7000H, GMH manufactured by Tosoh Corporation are used in combination.

The main peak molecular weight (Mp) of the THF soluble resin is usually 2500 to 10000, preferably 2000 to 8000. When the amount of the component having a molecular weight of less than 2500 increases, the heat resistant storage stability tends to deteriorate, and when the component having a molecular weight of more than 10,000 increases, the low-temperature fixability tends to decrease, but the decrease can be suppressed as much as possible by balance control. The content of the component having a molecular weight exceeding 10,000 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 may be deteriorated. The content of the component having a molecular weight of less than 2500 is 0.1 to 5.0%.
The number average molecular weight (Mn) of the THF-soluble resin is 2000 to 15000, and the value of Mw / Mn (Mw: weight average molecular weight) is preferably 5 or less. If it exceeds 5, sharp melt properties are lacking and glossiness is impaired. Moreover, hot offset resistance is improved by using a polyester resin containing 1 to 25% of THF insolubles.

  Although insoluble in THF is effective for hot offset resistance in color toners, it is definitely negative in terms of gloss and transparency of OHP, but it is effective within 1 to 10% for widening the mold release width. There are also cases that demonstrate this.

  The method for measuring the THF-insoluble resin content is shown below.

(Method for measuring THF insoluble matter)
About 1.0 g (A) of resin or toner is weighed.

  To this, about 50 g of THF is added and left at 20 ° C. for 24 hours.

  This is first separated by centrifugation and filtered using JIS standard (P3801) type 5 C filter paper for quantification.

  The solvent content of this filtrate is vacuum-dried, and only the resin content (residue) (B) is measured.

  This residual amount is THF-soluble.

  The THF insoluble content (%) is obtained from the following formula.

THF insoluble matter (%) = (A−B) / A × 100
In the case of toner, the THF insoluble component amount (W1) and the THF soluble component amount (W2) other than the resin are separately obtained by a known method, for example, a thermal loss method by the TG method, and obtained from the following formula.

THF insoluble matter (%) = (A−B−W2) / (A−W1−W2) × 100
The toner of the present invention is a solution or dispersion formed by dissolving or dispersing a toner component consisting of a binder component consisting of a modified polyester resin capable of reacting at least with active hydrogen and a colorant in an organic solvent. It is obtained by reacting with a cross-linking agent and / or an extender in a hydrogen medium, and removing the solvent from the resulting dispersion.

  Examples of the reactive modified polyester resin (RMPE) capable of reacting with active hydrogen used in the present invention include a polyester prepolymer (A) having an isocyanate group. Examples of the polar polymer (A) include a polycondensate of a polyol (PO) and a polycarboxylic acid (PC), and a polyester having active hydrogen further reacted with a polyisocyanate (PIC). Examples of the group containing active hydrogen in the polyester include a hydroxyl group (alcoholic hydrogen 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.

  An amine is used as a crosslinking agent for the reactive modified polyester resin, and a diisocyanate compound (diphenylmethane diisocyanate or the like) is used as an extender. Delete this part and do as follows. The amines described in detail later act as a crosslinking agent and an extender for the modified polyester capable of reacting with active hydrogen.

  Modified polyester such as urea-modified polyester obtained by reacting the polyester prepolymer (A) having an isocyanate group with an amine (B) can easily adjust the molecular weight of the polymer component, and is a dry toner, particularly oilless low-temperature fixing. It is convenient to ensure the characteristics (wide releasability and fixability without a release oil application mechanism to the fixing heating medium). Particularly, a polyester prepolymer whose end is modified with urea can suppress adhesion to a heating medium for fixing while maintaining high fluidity and transparency in the fixing temperature range of the unmodified polyester resin itself.

  A preferred polyester prepolymer used in the present invention is a polyester having an active hydrogen group such as an acid group or a hydroxyl group at the terminal, and a functional group such as an isocyanate group that reacts with the active hydrogen. A modified polyester (MPE) such as urea-modified polyester can be derived from this prepolymer, but in the case of the present invention, a preferred modified polyester used as a toner binder is a polyester prepolymer (A) having an isocyanate group. It is a urea-modified polyester obtained by reacting amines (B) as a crosslinking agent and / or an extender. The polyester prepolymer (A) having an isocyanate group is obtained by further reacting a polyester having an active hydrogen group, which is a polycondensate of a polyol (PO) and a polycarboxylic acid (PC), with a polyisocyanate (PIC). Can do. Examples of the active hydrogen group possessed by the polyester include hydroxyl groups (alcoholic hydroxyl groups and phenolic hydroxyl groups), amino groups, carboxyl groups, mercapto groups, and the like. Among these, alcoholic hydroxyl groups are preferred.

  Examples of the polyol (PO) include a diol (DIO) and a 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 (DIC) and trivalent or higher polycarboxylic acid (TC), and DIC alone or a mixture of DIC and a small amount of (TC) is preferable. Dicarboxylic acids (DIC) 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.

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

  The ratio of the polyisocyanate (PIC) is usually 5/1 to 1/1, preferably 4 /, as an equivalent ratio [NCO] / [OH] of the isocyanate group [NCO] and the hydroxyl group [OH] of the polyester having a hydroxyl group. 1 to 1.2 / 1, 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 (3) 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 prepolymer (A) having an isocyanate group is usually 1 or more, preferably 1.5 to 3 on average, more preferably 1.8 to 2.5 on average. It is. If it is less than 1 per molecule, the molecular weight of the urea-modified polyester will be low, and the hot offset resistance will deteriorate.

  As amines (B), diamine (B1), trivalent or higher polyamine (B2), aminoalcohol (B3), aminomercaptan (B4), amino acid (B5), and amino acids B1-B5 blocked (B6) etc. are mentioned. 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 B1 to B5 blocked amino groups (B6) include ketimine compounds and oxazolidine compounds obtained from the amines of B1 to B5 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, if necessary, the molecular weight of the polyester can be adjusted using an elongation terminator. Examples of the elongation terminator include monoamines (diethylamine, dibutylamine, butylamine, laurylamine, etc.), and those obtained by blocking them (ketimine compounds).

  The ratio of amines (B) is the equivalent ratio [NCO] / [NHx] of isocyanate groups [NCO] in the prepolymer (A) having isocyanate groups and amino groups [NHx] in amines (B). The ratio is usually 1/2 to 2/1, preferably 1.5 / 1 to 1 / 1.5, more preferably 1.2 / 1 to 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, the polyester-based resin (polyester) preferably used as a toner binder is urea-modified polyester (UMPE), but this polyester may contain a urethane bond together with 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.

  Modified polyester such as urea-modified polyester (UMPE) is produced by a one-shot method or the like. The weight average molecular weight of the modified polyester such as urea-modified polyester (UMPE) is usually 10,000 or more, preferably 20,000 to 10,000,000, more preferably 30,000 to 1,000,000. If it is less than 10,000, the hot offset resistance deteriorates. The number average molecular weight of a modified polyester such as a urea-modified polyester is not particularly limited when a non-modified polyester (PE) described later is used, and may be a number average molecular weight that can be easily obtained to obtain the weight average molecular weight. In the case of a modified polyester such as UMPE alone, the number average molecular weight is usually 2000-15000, preferably 2000-10000, and more preferably 2000-8000. When it exceeds 20000, the low-temperature fixability and the glossiness when used in a full-color apparatus are deteriorated.

  In the present invention, a modified polyester such as polyester modified with a urea bond (UMPE) is not only used alone, but also with this, unmodified polyester (PE) can be contained as a toner binder component. The combined use of PE improves low-temperature fixability and gloss when used in a full-color device, and is preferable to single use. Examples of PE include polycondensates of polyol PO and polycarboxylic acid PC similar to the polyester component of UMPE, and preferred ones are also the same as in UMPE. The weight average molecular weight (Mw) of PE is 10,000 to 300,000, preferably 14,000 to 200,000. Its Mn (number average molecular weight) is 1000 to 10000, preferably 1500 to 6000. For UMPE, not only unmodified polyesters but also those modified with chemical bonds other than urea bonds, such as those modified with urethane bonds, can be used in combination. UMPE and PE are preferably at least partially compatible with each other in terms of low-temperature fixability and hot offset resistance. Accordingly, the polyester component of UMPE and PE preferably have similar compositions. The weight ratio of UMPE to PE when PE is contained is usually 5/95 to 80/20, preferably 5/95 to 30/70, more preferably 5/95 to 25/75, particularly preferably 7/93. ~ 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 (mgKOH / g) of PE is preferably 5 or more, and the acid value (mgKOH / g) of PE is usually 1 to 30, preferably 5 to 20. By giving an acid value, it tends to be negatively charged, and further, the affinity between the paper and the toner is good when fixing to paper, 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 polymerization reaction, if the acid value is touched, it will cause blurring in the granulation process, making it difficult to control the emulsification.

  In the present invention, the glass transition point (Tg) of the toner binder is usually 40 to 70 ° C., preferably 40 to 60 ° C. If it is less than 40 ° C., the heat resistance of the toner deteriorates, and if it exceeds 70 ° C., the low-temperature fixability becomes insufficient. Due to the coexistence of a modified polyester such as a urea-modified polyester resin, the dry toner of the present invention tends to have good heat-resistant storage stability even when the glass transition point is low, as compared with a known polyester-based toner.

(Release agent)
As the wax used in the toner of the present invention, a low melting point wax having a melting point of 50 to 120 ° C. works more effectively as a release agent in the dispersion with the binder resin between the fixing roller and the toner interface, This shows an effect against high temperature offset resistance without applying a release material such as oil to the fixing roller.

  The melting point of the wax in the present invention was the maximum endothermic peak measured by a differential scanning calorimeter (DSC).

  The following materials can be used as the wax component that functions as a release agent that can be used in the present invention. That is, as specific examples, waxes and waxes include plant waxes such as carnauba wax, cotton wax, wood wax and rice wax, animal waxes such as beeswax and lanolin, mineral waxes such as ozokerite and cercin, And petroleum waxes such as paraffin, microcrystalline, and petrolatum. In addition to these natural waxes, synthetic hydrocarbon waxes such as Fischer-Tropsch wax and polyethylene wax, and synthetic waxes such as esters, ketones and ethers can be used. Furthermore, fatty acid amides such as 12-hydroxystearic acid amide, stearic acid amide, phthalic anhydride imide, and chlorinated hydrocarbon, and poly n-stearyl methacrylate and poly n-lauryl methacrylate which are low molecular weight crystalline polymer resins A crystalline polymer having a long alkyl group in the side chain, such as a polyacrylate homopolymer or copolymer (for example, a copolymer of n-stearyl acrylate-ethyl methacrylate, etc.) can also be used.

(Coloring agent)
As the colorant used in the present invention, all known dyes and pigments can be used. For example, 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 Lake, Anthrazan Yellow BGL, Isoindolinone Yellow, Bengala, Red Tan, Lead Zhu, Cadmium Red, Cadmium Mercury Red, Antimon Zhu, Permanent Red 4R , Para red, phissa red, parac Luort Nitroaniline Red, Resol Fast Scarlet G, Brilliant Fast Scarlet, Brilliant Carnmin 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, Tolujing 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, Pi Zoron Red, Polyazo Red, Chrome Vermilion, 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, Indance Ren 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 Gree Lake, phthalocyanine green, anthraquinone green, titanium oxide, zinc white, litbon and mixtures thereof can be used. The content of the colorant is usually 1 to 15% by weight, preferably 3 to 10% by weight, based on the toner.

  The colorant used in the present invention can also be used as a master batch combined with a resin. As the binder resin to be kneaded together with the production of the masterbatch or the masterbatch, in addition to the modified and unmodified polyester resins mentioned above, styrene such as polystyrene, poly p-chlorostyrene, polyvinyltoluene, and polymers of substituted products thereof; 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-malein 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 Acrylic resin, rosin, modified rosin, terpene resin, aliphatic or alicyclic hydrocarbon resin, aromatic petroleum resin, chlorinated paraffin, paraffin wax, etc. The

  This master batch can be obtained by mixing and kneading a resin for a master batch and a colorant under a high shear force to obtain a master batch. 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 called watering paste containing water of a colorant is mixed and kneaded together with a resin and an organic solvent, and the colorant is transferred to the resin side to remove moisture and organic solvent components. Since it can be used as it is, it does not need to be dried and is preferably used. For mixing and kneading, a high shear dispersion device such as a three-roll mill is preferably used.

  A method for producing an electrophotographic toner in which particles comprising a colorant and a resin and particles comprising at least charge control agent particles are mixed together in a container using a rotating body in order to adhere and immobilize the charge control agent on the toner particle surface. However, in this method, the object of the present invention is to include a step of mixing at a peripheral speed of the rotating body of 40 to 150 m / sec in a container without a fixing member protruding from the inner wall of the container. Toner particles are obtained. Next, the used toner will be described.

  The toner of the present invention may contain a charge control agent as necessary. Known charge control agents can be used, such as nigrosine dyes, triphenylmethane dyes, chromium-containing metal complex dyes, molybdate chelate pigments, rhodamine dyes, alkoxy amines, quaternary ammonium salts (fluorine-modified 4 Secondary ammonium salts or compounds, tungsten simple substances or compounds, fluorine activators, salicylic acid metal salts, and metal salts of salicylic acid derivatives. 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.

An external additive is used to assist the fluidity, developability, and chargeability of the colored particles obtained in the present invention, and inorganic fine particles can be preferably used as the external additive. 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, silica sand, clay, mica, wollastonite, diatomaceous earth. Examples include soil, chromium oxide, cerium oxide, pengala, antimony trioxide, magnesium oxide, zirconium oxide, barium sulfate, barium carbonate, calcium carbonate, silicon carbide, and silicon nitride. Among these, as the fluidity imparting agent, it is preferable to use hydrophobic silica fine particles and hydrophobic titanium oxide fine particles in combination. In particular, when stirring and mixing are performed using particles having an average particle size of 50 mμ or less, the electrostatic force and van der Waals force with the toner are remarkably improved, so that a desired charge level is obtained. It is clear that even with stirring and mixing inside the developing machine, a fluidity imparting agent is not detached from the toner, a good image quality that does not cause firefly and the like can be obtained, and further, the residual toner can be reduced. became.

  Titanium oxide fine particles are excellent in environmental stability and image density stability, but have a tendency to deteriorate the charge rising characteristics, and therefore, if the amount of titanium oxide fine particles added is larger than the amount of silica fine particles added, the side effect of It can be considered large. However, when the addition amount of the hydrophobic silica fine particles and the hydrophobic titanium oxide fine particles is in the range of 0.3 to 1.5 wt%, the charge rising characteristics are not greatly impaired, and the desired charge rising characteristics can be obtained, that is, repeated copying. It has been found that stable image quality can be obtained and toner blowing can be suppressed even if the process is performed.

  The resin for toner binder can be produced by the following method. Polyol (PO) and polycarboxylic acid (PC) are heated to 150-280 ° C. in the presence of a known esterification catalyst such as tetrabutoxytitanate, dibutyltin oxide, etc., and the generated water is distilled off as necessary. Thus, a polyester having a hydroxyl group is obtained. Next, this is reacted with polyisocyanate (PIC) at 40 to 140 ° C. to obtain a polyester prepolymer (A) having an isocyanate group. Further, this A is reacted with amines (B) at 0 to 140 ° C. to obtain a polyester (UMPE) modified with a urea bond. The number average molecular weight of this modified polyester is 1000 to 10000, preferably 1500 to 6000. When reacting PIC and when reacting A and B, a solvent can be used if necessary. Usable solvents include aromatic solvents (toluene, xylene, etc.); ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.); esters (ethyl acetate, etc.); amides (dimethylformamide, dimethylacetamide, etc.) and ethers And those inert to isocyanates (PIC) such as tetrahydrofuran (such as tetrahydrofuran). When polyester (PE) that is not modified with a urea bond is used in combination, PE is produced in the same manner as the polyester having a hydroxyl group, and this is dissolved in the solution after completion of the UMPE reaction and mixed.

  The dry toner of the present invention can be produced by the following method, but is not limited thereto.

(Toner production method in aqueous medium)
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 miscible solvents include alcohol (methanol, isopropanol, ethylene glycol, etc.), dimethylformamide, tetrahydrofuran, cellosolves (methyl cellosolve, etc.), lower ketones (acetone, methyl ethyl ketone, etc.), and the like.

  In the present invention, a urea-modified polyester (UMPE) or the like can be obtained by reacting a reactive modified polyester such as a polyester prepolymer (A) having an isocyanate group with an amine (B) in an aqueous medium. As a method for stably forming a dispersion comprising a modified polyester such as urea-modified polyester or a reactive modified polyester such as prepolymer (A) in an aqueous medium, a modified polyester such as urea-modified polyester or a pre-polymer can be used in an aqueous medium. Examples thereof include a method in which a composition of a toner raw material composed of reactive modified polyester such as polymer (A) is added and dispersed by shearing force. Reactive modified polyester such as prepolymer (A) and other toner composition (hereinafter referred to as toner raw material), colorant, colorant masterbatch, release agent, charge control agent, unmodified polyester resin, etc. Although mixing may be performed when forming the dispersion in the medium, it is more preferable to mix the toner raw materials in advance and then add and disperse the mixture in the aqueous medium. In the present invention, other toner materials such as a colorant, a release agent, and a charge control agent do not necessarily have to be mixed when forming particles in an aqueous medium, but after the particles are formed. , May be added. For example, after forming particles containing no colorant, the colorant can be added by a known dyeing method.

  The dispersion method is not particularly limited, and known equipment such as a low-speed shear method, a high-speed shear method, a friction method, a high-pressure jet method, and an ultrasonic wave can be applied. In order to make the particle size of the dispersion 2 to 20 μm, a 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 of the urea-modified polyester or prepolymer (A) has a low viscosity and is easy to disperse.

  The amount of the aqueous medium used is usually 50 to 2000 parts by weight, preferably 100 to 1000 parts by weight, based on 100 parts of the toner composition containing a polyester such as urea-modified polyester and prepolymer (A). If the amount is less than 50 parts by weight, the dispersion state of the toner composition is poor, and toner particles having a predetermined particle diameter cannot be obtained. If it exceeds 20000 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.

  Various dispersants for emulsifying and dispersing the oily phase in which the toner composition is dispersed are used in the liquid containing water. Such a dispersant includes a surfactant, an inorganic fine particle dispersant, a polymer fine particle dispersant and the like.

  As surfactants, anionic surfactants such as alkylbenzene sulfonates, α-olefin sulfonates, phosphate esters, alkylamine salts, amino alcohol fatty acid derivatives, polyamine fatty acid derivatives, amine salt types such as imidazoline, Quaternary ammonium salt type cationic surfactants such as alkyltrimethylammonium salt, dialkyldimethylammonium salt, alkyldimethylbenzylammonium salt, pyridinium salt, alkylisoquinolinium salt, benzethonium chloride, fatty acid amide derivative, polyhydric alcohol Nonionic surfactants such as derivatives, for example, amphoteric surfactants such as alanine, dodecyldi (aminoethyl) glycine, di (octylaminoethyl) glycine and N-alkyl-N, N-dimethylammonium betaine. It is.

  Further, by using a surfactant having a fluoroalkyl group, the effect can be obtained in a very small amount. 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 (Daikin Kogyo Co., Ltd.), MegaFuck 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 Fgentent F-100, F150 (manufactured by Neos).

  In addition, as the cationic surfactant, aliphatic quaternary ammonium salts such as aliphatic primary, secondary or secondary amic acid, perfluoroalkyl (C 6 -C 10) sulfonamidopropyltrimethylammonium salt which right the fluoroalkyl group, Benzalkonium salts, benzethonium chloride, pyridinium salts, imidazolinium salts, trade names include Surflon S-121 (manufactured by Asahi Glass), Florard FC-135 (manufactured by Sumitomo 3M), Unidyne DS-202 (manufactured by Daikin Industries) ), Megafuck F-150, F-824 (manufactured by Dainippon Ink, Inc.), Xtop EF-132 (manufactured by Tochem Products), and Footgent F-300 (manufactured by Neos).

  Moreover, tricalcium phosphate, calcium carbonate, acid value titanium, colloidal silica, hydroxyapatite, etc. can be used as an inorganic compound dispersant which is hardly soluble in water.

  Further, the same effect as that of the inorganic dispersant was confirmed for the fine particle polymer. For example, MMA polymer fine particles 1 μm and 3 μm, styrene fine particles 0.5 μm and 2 μm, styrene-acrylonitrile fine particle polymer 1 μm, (PB-200H (Kao) SGP (Soken), Technopolymer SB (Sekisui Plastics), SGP-3G (Soken) Micropearl (Sekisui Fine Chemical)).

  In addition, as a dispersant that can be used in combination with the above inorganic dispersant and fine particle polymer, the dispersed droplets may be stabilized by a polymer protective colloid. For example, acrylic acid, methacrylic acid, α-cyanoacrylic acid, α-cyanomethacrylic acid, itaconic acid, crotonic acid, fumaric acid, maleic acid or maleic anhydride and other (meth) acrylic monomers containing hydroxyl groups Bodies such as β-hydroxyethyl acrylate, β-hydroxyethyl methacrylate, β-hydroxypropyl acrylate, β-hydroxypropyl methacrylate, γ-hydroxypropyl acrylate, γ-hydroxypropyl methacrylate, 3-acrylate Chloro-2-hydroxypropyl, 3-chloro-2-hydroxypropyl methacrylate, diethylene glycol monoacrylate, diethylene glycol monomethacrylate, glycerol monoacrylate, glycerol monomethacrylate, N -Methylol acrylamide, N-methylol methacrylamide, etc., vinyl alcohol or ethers with vinyl alcohol, such as vinyl methyl ether, vinyl ethyl ether, vinyl propyl ether, etc., or esters of compounds containing vinyl alcohol and carboxyl groups, such as Pinyl acetate, pinyl propionate, vinyl butyrate, acrylamide, methacrylamide, diacetone acrylamide or their methylol compounds, acid chlorides such as acrylic acid chloride, methacrylic acid chloride, pinylviridine, vinylpyrrolidone, vinylimidazole, ethyleneimine, etc. Homopolymers or copolymers such as those having nitrogen atoms or heterocyclic rings thereof, polyoxyethylene, polyoxypropylene, polymers Oxyethylene alkylamine, polyoxypropylene alkylamine, polyoxyethylene alkylamide, polyoxypropylene alkylamide, polyoxyethylene nonyl phenyl ether, polyoxyethylene lauryl phenyl ether, polyoxyethylene stearyl phenyl ester, polyoxyethylene nonylphenyl Polyoxyethylenes such as esters, celluloses such as methyl cellulose, hydroxyethyl cellulose, and hydroxypropyl cellulose can be used.

  In order to remove the organic solvent from the obtained emulsified dispersion (reactant), the entire system is gradually heated in a laminar stirring state, subjected to strong stirring in a certain temperature range, and then the solvent is removed. By doing so, spindle-shaped toner particles can be produced. In addition, when an acid such as calcium phosphate salt or an alkali-soluble substance is used as the dispersion stabilizer, the calcium phosphate salt is removed from the fine particles by a method such as dissolving the calcium phosphate salt with an acid such as hydrochloric acid and washing with water. To do. It can also be removed by operations such as enzymatic degradation.

  When a dispersant is used, the dispersant can remain on the toner particle surface.

  Furthermore, in order to reduce the viscosity of the dispersion medium containing the toner composition, a solvent in which a polyester such as urea-modified polyester or prepolymer (A) is soluble can be used. 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, the solvent (solvent) is removed from the resultant reaction product under normal pressure or reduced pressure after the extension and / or crosslinking reaction of the modified polyester (prepolymer) with an amine.

  According to the solvent removal conditions, the formation state of the SF-1 and SF-2 of the toner can be appropriately adjusted. In order to adjust the indentation to an appropriate diameter, it is necessary to set solvent removal conditions in addition to the dispersing agent described above. As the conditions, the oil phase solid content of the liquid emulsified and dispersed in an aqueous medium is used. The solvent removal temperature must be 5 to 50%, the solvent removal temperature is 10 to 50 ° C., and the solvent removal time must be within 30 minutes as the residence time when the toner is removed. This is probably because the solvent contained in the oil phase evaporates in a short time, so that the oil phase is relatively hard and the elastic oil phase is unbalanced by low temperature. When the oil phase solid content is more than 50%, the evaporation solvent is small and the conditions for volume shrinkage are reduced, and when it is less than 5%, the productivity is remarkably reduced. As time increases, volume shrinkage is less likely to occur, so that it becomes spherical and SF-1 becomes smaller and spherical. However, the above conditions are not absolute conditions, and it is necessary to balance temperature and solvent removal time.

  The elongation and / or crosslinking reaction time is selected, for example, depending on the reactivity of the isocyanate group structure of the prepolymer (A) and the amines (B), but is usually 10 minutes to 40 hours, preferably 2 to 24 hours. 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. In addition, as an extender and / or a crosslinking agent, the above-described amines (B) are used.

  In the present invention, prior to desolvation from the dispersion (reaction liquid) after the elongation and / or cross-linking reaction, a shape control step of stirring the dispersion in a stirring tank having no baffle plate or projections on the wall surface. It is preferable to remove the solvent at 10 to 50 ° C. after the liquid is stirred with a strong stirring force. The toner shape SF-1 can be controlled by the liquid stirring before the solvent removal. The emulsion emulsified and dispersed in an aqueous medium and further subjected to extension reaction is stirred with a strong stirring force of 30 to 50 ° C. in a stirring tank having no baffle plate or protrusion before solvent removal, and the toner shape is spindle-shaped. After confirming the above, the solvent is removed at a solvent removal temperature of 10 to 50 ° C. Since this condition is not an absolute condition, it is necessary to appropriately select the condition. However, a spindle-like shape can be formed by applying an elongation reaction after emulsification and dispersion and then applying a shear with a strong stirring force in a stirring tank. This is presumed that ethyl acetate or the like contained in the granulation changed from a spherical shape to a spindle shape by lowering the viscosity of the emulsified liquid with a stronger stirring force.

  On the other hand, the ratio Dv / Dn of the volume average particle diameter Dv and the number average diameter (Dn) of the toner is controlled mainly by adjusting, for example, the water layer viscosity, the oil layer viscosity, the characteristics of the resin fine particles, the addition amount, and the like. can do. Further, Dv and Dn can be controlled by adjusting, for example, characteristics of resin fine particles, addition amount, and the like.

  The toner of the present invention can be used as a two-component developer. In this case, it may be used by mixing with a magnetic carrier, and the content ratio of the carrier to the toner in the developer is preferably 1 to 10 parts by weight of the toner relative to 100 parts by weight of the 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 resin such as vinyl, polyester resin such as polyethylene terephthalate resin and polybutylene terephthalate resin, polycarbonate resin, polyethylene resin, polyvinyl fluoride resin, polyvinylidene fluoride resin, polytrifluoroethylene resin, 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 contain electrically conductive powder etc. 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.

  The image forming method of the present invention is a method of using the toner of the present invention as the toner in a conventional image forming method using toner.

  The image forming apparatus of the present invention is an apparatus using the toner of the present invention as the toner in a conventional image forming apparatus using toner.

  The present invention will be described below with reference to the drawings.

  FIG. 1 is a cross-sectional configuration diagram of a main part of an example of an image forming apparatus. In this example, an electrophotographic copying machine is illustrated as an image forming apparatus. In FIG. 1, reference numeral 1 denotes a photosensitive drum as a latent image carrier, which rotates in the direction of the arrow in the drawing, and a charger 2 is disposed around the photosensitive drum 3 so that a laser beam 3 corresponding to an image read from a document. Are irradiated as exposure means. Further, a developing device 4, a paper feeding unit 7, a transfer device 5, a cleaning device 6, and a charge eliminating lamp 9 are disposed around the photoreceptor 1. The developing device 4 further includes developing rollers 41 and 42, a paddle-like stirring member 43, a stirring member 44, a doctor 45, a toner supply unit 46, and a supply roller 47. The cleaning means 6 includes a cleaning brush 61 and a cleaning blade 62. Members 81 and 82 arranged above and below the developing device 4 are guide rails for attaching / detaching or supporting the developing device.

  The life of the cleaning blade 61 of the cleaning device can also be detected. The cleaning blade 61 always abuts on the photoconductor during image formation and wears as the photoconductor rotates. When the cleaning blade is worn, the function of removing the residual toner on the surface of the photoreceptor is lowered, and the copy image quality is deteriorated. Even if the toner is not worn, the transferability is improved when the toner is close to a true sphere and the fluidity is improved as compared with the pulverized toner. However, in cleaning, it is easy to cause defective cleaning through the installed blade. Is done. By using the toner of the present invention with respect to this problem, it can be satisfactorily cleaned.

  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.

  Table 1 summarizes the toner used in each example.

Example 1
In a reaction vessel equipped with a cooling tube, a stirrer, and a nitrogen introduction tube, 690 parts of bisphenol A ethylene oxide 2-mole adduct and 256 parts of terephthalic acid were subjected to polycondensation at 230 ° C. for 8 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).

(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-mole adduct, 180 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).

(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 12,000 rpm for 5 minutes with a TK homomixer at 60 ° C, and dispersed at 20 ° C for 30 minutes with a bead mill. did. This is designated as toner material solution (1).

  Next, 306 parts of ion-exchanged water, 265 parts of tricalcium phosphate 10% suspension, and 0.2 part of sodium dodecylbenzenesulfonate were placed in a beaker and dissolved uniformly. The toner material solution (1) and 2.7 parts of the ketimine compound (1) were then added and reacted with urea while stirring at 12000 rpm with a TK homomixer. When the particle size is large while observing the particle size and particle size distribution with an optical microscope, the stirring speed is increased to 14000 and the process is further performed for 5 minutes. If it is smaller, change the stirring to 10,000 rpm and repeat the experiment. Next, 500 g of this mixed solution is weighed and transferred to a round bottom Kolben equipped with a stir bar and a thermometer, heated to 45 ° C., and stirred rapidly at 200 to 400 revolutions for 2 hours to obtain spindle-shaped base toner particles. It was. If the spindle shape is insufficient, the stirring time is extended. Thereafter, the solvent was removed under reduced pressure for 1.0 hour, filtered, washed and dried, followed by air classification to obtain spindle-shaped base particles.

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

  Further, 0.5 part of hydrophobic silica (H2000, manufactured by Clariant Japan Co., Ltd.) was added, the peripheral speed was 15 m / sec, mixing was performed for 30 seconds and suspended for 1 minute for 5 cycles to obtain a cyan toner. Next, 0.5 part of hydrophobic silica and 0.5 part of hydrophobic titanium oxide were mixed with a Henschel mixer to obtain toner (1) of the present invention.

Example 2
(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).

(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, 15.4 parts of the prepolymer (1), 50 parts of polyester (a) and 95.2 parts of ethyl acetate were stirred and dissolved. Next, 20 parts of carnauba wax (molecular weight 1800, acid value 2.5, needle penetration degree 1.5 mm / 40 ° C.) and 3 parts of copper phthalocyanine blue pigment were added and stirred at 10000 rpm with a TK homomixer at 85 ° C. The mixture was dispersed in the same manner as in Example 1 using a bead mill. Thereafter, the same operation as in Example 1 was performed to obtain base toner particles (2).

  Next, a toner (2) was produced in the same manner as in Example 1 except that the base particles and the charge control agent (Orient Chemical Co., Ltd., Bontron E-89) were used.

Example 3
(Prepolymer production example)
In a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen introducing tube, 100 parts of bisphenol A ethylene oxide 2-mole adduct, 130 parts of isophthalic acid and 2 parts of dibutyltin oxide were placed and reacted at 230 ° C. for 8 hours at normal pressure. Furthermore, after reacting for 5 hours while dehydrating at a reduced pressure of 10 to 15 mmHg, the mixture was cooled to 160 ° C. to obtain a hydroxyl group-containing prepolymer (3).

(Example of dead polymer production)
In the same manner as above, 589 parts of bisphenol A ethylene oxide 2-mole adduct and 464 parts of dimethyl terephthalate were polycondensed at 230 ° C. for 6 hours under normal pressure, and then reacted at a reduced pressure of 10 to 15 mmHg for 5 hours to give a dead polymer ( I) was obtained.

(Example of toner production)
In a beaker, 15.3 parts of the prepolymer (3), 63.6 parts of dead polymer (I), 40 parts of toluene and 40 parts of ethyl acetate were stirred and dissolved. Next, 10 parts of rice WAX and 4 parts of copper phthalocyanine blue pigment were added, and the mixture was stirred at 12,000 rpm with a TK homomixer at 60 ° C., and then dispersed at 25 ° C. for 30 minutes with a bead mill. Finally, 1.1 parts of diphenylmethane diisocyanate was added as an extender and dissolved. This is designated as toner material solution (2).

  In a beaker, 406 parts of ion-exchanged water, 294 parts of a 10% tricalcium phosphate suspension and 0.2 part of sodium dodecylbenzenesulfonate were uniformly dissolved. Next, the temperature was raised to 60 ° C., and the toner material solution (2) was added while stirring at 12000 rpm with a TK homomixer and stirred for 10 minutes. Next, 500 g of this mixed solution was transferred to a Kolben equipped with a stir bar and a thermometer, heated to 50 ° C. in 30 minutes, allowed to undergo urethanization reaction, stirred for 25 minutes at 300 rpm, then the solvent was removed, filtered, After washing and drying, air classification was performed to obtain spindle-shaped base particles of the present invention. Toner 3 was obtained in the same manner as in Example 1.

Example 4
(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 (4).

(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, 15.4 parts of the prepolymer (1), 50 parts of polyester (a) and 95.2 parts of ethyl acetate were stirred and dissolved. Next, 20 parts of carnauba wax (molecular weight 1800, acid value 2.5, needle penetration degree 1.5 mm / 40 ° C.) and 3 parts of copper phthalocyanine blue pigment were added and stirred at 12000 rpm with a TK homomixer at 85 ° C. After being uniformly dispersed, it was dispersed at 15 ° C. for 50 minutes by a bead mill. This is designated as toner material solution (4).

  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 uniformly dissolved. Next, the temperature was raised to 40 ° C., and while stirring at 12000 rpm with a TK homomixer, the toner material solution (4) was added and stirred for 10 minutes, and then 2.7 parts of a ketimine compound (1) was added to cause an extension reaction. . Next, this mixed solution was transferred to a Kolben equipped with a stirring bar and a thermometer, and stirred at 300 rpm for 2 hours at 40 ° C. to produce spindle-shaped base toner particles. Thereafter, the solvent was removed at 40 ° C. for 1 hour, and after filtration, washing, and drying, spindle-shaped base particles (4) were obtained. At this time, the concentration of the emulsified dispersion was 13%. In the same manner as in Example 1, a toner 4 was obtained.

Comparative Example 1
(Toner binder synthesis)
A comparative toner binder (Comparative 1) was obtained by polycondensation of 395 parts of bisphenol A ethylene oxide 2-mole adduct and 166 parts of isophthalic acid using 2 parts of dibutyltin oxide as a catalyst.

(Create toner)
In a beaker, 100 parts of the above comparative toner binder (Comparative 1), 180 parts of ethyl acetate solution, 4 parts of copper phthalocyanine blue pigment, 10% solution of hydroxyapatite as a dispersant (Super Tight 10 manufactured by Nippon Chemical Industry Co., Ltd.) and dodecyl Sodium benzenesulfonate was added and stirred at 10000 rpm with a TK homomixer at 50 ° C. to uniformly dissolve and disperse. Next, the toner was formed in the same manner as in Example 1, but the solvent was removed over 8 hours by slowly stirring in the solvent removal step. To 100 parts of toner particles, 0.3 part of hydrophobic silica and 0.3 part of hydrophobic titanium oxide were mixed using a Henschel mixer.

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, a urethane-modified polyester was obtained. . Bisphenol A ethylene oxide 2-mole adduct 363 parts and isophthalic acid 166 parts were polycondensed in the same manner as in Example 1 to obtain an unmodified polyester. 350 parts of the urethane-modified polyester and 650 parts of the unmodified polyester were dissolved in toluene, mixed, and then the solvent was removed to obtain a comparative toner binder (Comparative 2).

(Create toner)
100 parts of a comparative toner binder (2), 2 parts of a chromium salicylate complex (E-81 manufactured by Orient Chemical Co., Ltd.) as a charge control agent, and 4 parts of a copper phthalocyanine blue pigment were formed into a toner by the following method. First, after preliminary mixing using a Henschel mixer, the mixture was kneaded with a continuous kneader. Next, the mixture was finely pulverized with a jet pulverizer and then classified with an airflow classifier. To 100 parts of toner particles, 0.3 part of hydrophobic silica and 0.3 part of hydrophobic titanium oxide were mixed using a Henschel mixer.

Comparative Example 3
Polyester resin (bisphenol-based resin, manufactured by Kao Corporation) 90 parts (Mn = 6000, Mw = 70000, Tg = 64 ° C.)
Carbon black (BP1300, manufactured by Cabot Corporation) 10 parts Rice wax (melting point 82 ° C.) 10 parts Diethyl ether / dichloromethane mixed solution (50:50) 300 g
The above components were mixed and dispersed for 10 hours by a ball mill. The obtained dispersion was put into 400 g of a 2% aqueous solution of gum arabic and dispersed for 3 minutes by a homomixer. Thereafter, it was poured into 2000 g of pure water, kept at 80 ° C. in a water bath, and kept for 4 hours while stirring with a three-one motor. As a result, amorphous particles having no regularity having recesses having an average particle diameter of 6.0 μm were obtained. The temperature of the suspension in this state is raised to 98 ° C., held at that temperature for 1 hour, and spheroidized while maintaining almost the same particle diameter, and a charge control agent is added with a Q mixer as in Example 1 to compare toner 3 Got .

Properties of the toner obtained in the previous SL Examples 1-4 and Comparative Examples 1-3 are shown in Table 1.

Table 2 shows the performance evaluation results of the toners obtained in Examples 1 to 4 and Comparative Examples 1 to 3 .

［評価方法］
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[Evaluation methods]
(1) Tg (° C)
A method for measuring Tg will be 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 (mgKOH / g) and hydroxyl value (mg / g)
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 was measured using a powder tester made 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
A: 0.35 or more (4) Heat-resistant storage stability After storing the toner at 50 ° C. for 8 hours, the toner was screened with a 42 mesh screen for 2 minutes, and the residual ratio on the wire mesh was defined as the heat-resistant storage stability. A toner having better heat-resistant storage stability has a lower residual ratio. The following four levels were evaluated.

×: 30% or more △: 20-30%
○: 10 to 20%
A: Less than 10% (5) Minimum fixing temperature (° C.)
Using a device in which the fixing unit of the Ricoh Co., Ltd. imagio NEO450 was modified as a fixing roller, type 6200 paper made by Ricoh was set on this and a copying test was performed. 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.

* The fixing device was modified, and a metal cylinder with a thickness of 0.34 mm was used for the metal cylinder of the fixing roller. The surface pressure was set to 1.0 × 10 ⁵ Pa.

(6) 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 having the fixing roll temperature at which the hot offset occurred was determined as the hot offset generation temperature.

(7) Charging stability The amount of charge at low temperature and low humidity and high temperature and high humidity is measured by the blow method, and the fluctuation range is evaluated. Silicone resin-coated iron powder is used for the carrier, and the environment should be measured with little change when measured at 30 ° C 90% and 10 ° C 30%.

×: Unusable △: Large difference ○: Slightly large difference ◎: Small difference and stable Application Example 1
With respect to Examples 1 to 4 and Comparative Examples 1.2 and 3, image evaluation and transferability evaluation were carried out using a Ricoh-made imagio Color4000 remodeling machine. The microdot reproducibility was also evaluated. Microdot reproducibility is to output a 1-dot independent image (1200 dpi) and evaluate dot reproducibility with respect to the latent image on the photoconductor, and perform a five-level evaluation (rank 5 is the highest point) by microscopic observation. It was. The results are shown in Table 3.

FIG. 2 is a cross-sectional configuration diagram of a main part of an example of an image forming apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Photosensitive drum 2 Charging device 3 Laser beam 4 Developing device 5 Transfer device 6 Cleaning device 9 Static elimination lamp

Claims (13)

A toner comprising at least a binder resin and a colorant, granulated in an aqueous medium,
The ratio Dv / Dn between the volume average particle diameter (Dv) and the number average particle diameter (Dn) of the toner is 1.00 to 1.30,
The main component of the binder resin is a modified polyester resin and an unmodified polyester resin,
The weight ratio (modified / unmodified) between the modified polyester resin and the unmodified polyester resin is 5/95 to 80/20,
The shape factor SF-1 of the toner is Ri 150-180 der, and
The toner shape factor SF-2 of the toner is characterized 100-130 der Rukoto.   The toner according to claim 1, wherein Dv / Dn of the toner is 1.00 to 1.20. The toner according to claim 1 or 2 volume average particle diameter Dv is characterized in that it is a 3.0～7.0Myuemu. A modified polyester resin capable of reacting with active hydrogen, a colorant and a release agent are dispersed in an aqueous medium in the presence of a dispersant, and the resulting dispersion is reacted with a crosslinking agent and / or an extender. the toner according to any one of claims 1 to 3, characterized in that the dispersion was a toner obtained by removing the solvent. A dispersion obtained by dispersing a toner composition comprising a modified polyester resin capable of reacting with active hydrogen in an organic solvent, a colorant, and a release agent in the presence of a dispersant is dispersed in an aqueous medium. The toner according to claim 4 , wherein the toner is obtained by reacting with an elongation agent and removing the solvent from the obtained dispersion. A dispersion obtained by dispersing a toner composition composed of a modified polyester resin capable of reacting with active hydrogen in an organic solvent, a colorant, and a release agent in the presence of a dispersant is dispersed in an aqueous medium. It is a toner obtained by reacting with an extender and stirring the obtained dispersion in a stirring tank free from baffles and protrusions, and then removing the solvent from the dispersion at 10 to 50 ° C. The toner according to claim 5 . In the molecular weight distribution of tetrahydrofuran-soluble resin component in the toner, a main peak is present in the molecular weight region of 2500 - 10000, and of claims 1-6 where the insoluble resin component tetrahydrofuran, characterized in that it contains 1% to 25% The toner according to any one of the above. 8. The toner according to claim 7 , wherein a component having a molecular weight of less than 2500 is 0.1 to 5.0% in the molecular weight distribution of the tetrohydrofuran-soluble resin in the toner. The glass transition point of the modified polyester resin in the toner is 40 to 70 ° C.,
The toner according to any one of claims 4 to 8 , wherein the toner has an acid value of 1 to 30 mgKOH / g. The toner according to any one of claims 1 to 9, characterized in that the toner used in the two-component developer. In an image forming method comprising a transfer step of transferring a toner image carried on a toner image carrier to a transfer material, and a cleaning step of cleaning toner remaining on the surface of the toner image carrier using a blade after the transfer.
An image-forming method, comprising the use of a toner according to any one of claims 1-10. An image forming apparatus comprising: a transfer unit that transfers a toner image carried on a toner image carrier to a transfer material; and a cleaning unit that uses a blade to clean toner remaining on the surface of the toner image carrier after the transfer.
An image forming apparatus characterized by the use of a toner according to any one of claims 1-10. An image forming apparatus in which a toner image on a transfer material is fixed by heating and melting by passing between two rollers, and a surface pressure (roller load / contact area) applied between the two rollers is 1. In an image forming apparatus for fixing at 5 × 10 ⁵ Pa or less,
An image forming apparatus characterized by the use of a toner according to any one of claims 1-10.

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