JP5434133B2 - Method for producing toner for developing electrostatic image - Google Patents

Description

The present invention relates to a toner and a developer for developing an electrostatic image in electrophotography, electrostatic recording, electrostatic printing and the like. More particularly relates to an electrophotographic developing system copying machine using a laser printer and plain paper facsimile producing how the toner for developing electrostatic images used for.

  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 toner and 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 small particle size and a uniform particle size causes a difficulty in cleaning. 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 technical information related to such a toner, Patent Document 1 proposes a toner made of polyester having Wadell's practical sphericity of 0.90 to 1.00. Here, a polyester modified with a urethane bond is used as a toner binder, and the resulting solution or dispersion is dissolved or dispersed in a solvent together with a colorant by a dispersion granulation method described in Patent Document 2, for example. A method is described in which a liquid is dispersed in an aqueous medium, and then the temperature of the mixed liquid is raised to remove the solvent, followed by filtration, drying, and classification to obtain toner particles.

  In addition, the polymerized toner method includes, for example, suspension polymerization as described in Patent Document 3, as well as an emulsion polymerization method and a solution suspension method that are relatively easy to be modified, and in the emulsion polymerization method, styrene monomer can be completely removed. The removal of emulsifiers and dispersants is difficult, and the problem with toners is becoming increasingly greater as environmental problems have been particularly highlighted. In the dissolution suspension method such as Patent Document 4, there is an advantage that a polyester resin capable of low-temperature fixing can be used, but in order to achieve oil-less fixing, the resin is used in polymer control and production to widen the mold release width. In the process of dissolving or dispersing the colorant in the solvent, a high molecular weight component is added, so that the liquid viscosity increases and productivity problems are likely to occur.

  Further, in the production method described in the above document, there is always a solvent removal step, but generally the solvent removal under reduced pressure by a batch type evaporator. Considering industrial continuous production, it is necessary to increase the efficiency of the process. In Patent Document 5, a toner composition is dissolved or dispersed in an organic solvent, the dissolved or dispersed material is dispersed in an aqueous medium in which a fine particle dispersant is present, and the resulting emulsified dispersion is subjected to continuous vacuum defoaming. A method has been proposed in which the organic solvent is introduced into a machine, thinned by centrifugal force, and the organic solvent is removed while applying a shearing force to the emulsified dispersion. Here, it is considered that the environment for removing the organic solvent is lower than the atmospheric pressure, and that the inert gas is supplied when the solvent is removed while applying a shearing force to the emulsified dispersion to efficiently produce the toner. Has been. However, the organic solvent removal efficiency greatly depends on the physical properties of the emulsified dispersion.

The subject of this invention is as follows.
(1) To provide a toner and an image forming apparatus excellent in low-temperature fixability.
(2) Toner having both low-temperature fixability and charging stability is provided.
(3) To provide a highly efficient manufacturing method by shortening the time of the solvent removal step.

In order to solve the above problems, the following inventions (1) to (6) are provided.
(1) At least a binder resin and / or a binder resin precursor, a colorant and a release agent are dissolved or dispersed in an organic solvent, and an oil phase composed of the solution or the dispersion is emulsified in an aqueous medium. Granulating and removing the organic solvent from the emulsion to obtain toner base particles,
In the step of removing the organic solvent from the emulsion, the inner tube wall surface is heated by a heat medium in the outer tube using an apparatus including the following means (a) to (d), and the pressure is reduced by a vacuum pump: In addition, the emulsion is supplied into the inner tube in which the rotor blades are rotated to form a thin film of the emulsion on the inner wall of the inner tube by centrifugal force, and the inside of the inner tube is controlled below the glass transition temperature of the toner. Draining the organic solvent in the emulsion and taking out the remaining emulsion,
The emulsion to be supplied to the step has a viscosity measurement value of 50 to 800 mPa · s at 25 ° C. and a Brookfield viscometer rotation speed of 60 rpm, and the emulsion has an interfacial tension of 15 dyn / cm to 35 dyn / cm. is there,
A method for producing a toner for developing an electrostatic charge image.
(A) an inner tube for removing the organic solvent in the emulsion, and an outer tube outside the inner tube for containing the heat medium and heating the inner tube,
(B) The upper and lower surfaces of the inner tube and the outer tube are sealed, and the inner tube has a rotating blade fixed to the upper surface of the inner tube and reaching further below the central portion of the inner tube,
(C) The upper portion of the outer pipe has a raw material supply port penetrating from the outside to the inner pipe,
(D) at the lower part of the inner pipe, on the same side as the supply port, a residual liquid outlet for taking out the remaining emulsion consisting of a pipe connected to the inner pipe, on the side opposite to the residual liquid outlet, and Above the position of the residual liquid outlet, a vapor outlet for discharging the solvent vapor consisting of a pipe connected to the inner pipe is provided.
(2) The oil phase contains at least a polymer having a site capable of reacting with a compound having an active hydrogen group, a binder resin, a colorant, and a release agent, and the oil phase is dispersed in an aqueous medium containing resin fine particles. Then, after the polymer having a site capable of reacting with the compound having the active hydrogen group is reacted or while reacting, the organic solvent is removed to obtain toner base particles. A method for producing a toner for image development.
(3) The method for producing a toner for developing an electrostatic charge image according to (1) or (2), wherein the binder resin contains a polyester resin.
(4) The method for producing a toner for developing an electrostatic charge image according to (3), wherein the acid value of the polyester resin is 1.0 to 50.0 (mgKOH / g).
(5) The method for producing a toner for developing an electrostatic charge image according to (3) or (4), wherein the polyester resin has a glass transition point of 35 to 65 ° C.
(6) The electrostatic image developing toner according to (2), wherein the polymer having a site capable of reacting with the compound having an active hydrogen group has a weight average molecular weight of 3,000 to 100,000. Manufacturing method .

  According to the present invention, it is possible to provide both a charging stability and a low-temperature fixing property of the toner, and provide a highly efficient toner production method by shortening the time of the solvent removal step.

It is a schematic block diagram which shows an example of the organic solvent removal apparatus used in this invention. It is a schematic block diagram which shows an example of the image forming apparatus used for implementation of the image forming method of this invention. It is a schematic block diagram which shows the other example of the image forming apparatus used for implementation of the image forming method of this invention. It is a schematic block diagram which shows the example of the tandem type color image forming apparatus used for implementation of the image forming method of this invention. FIG. 5 is a partially enlarged schematic configuration diagram of the image forming apparatus illustrated in FIG. 4. It is a schematic block diagram which shows an example of the process cartridge of this invention.

  Hereinafter, the present invention will be described in detail.

  As described above, the method for producing a toner of the present invention comprises dispersing an oil phase containing a toner composition such as a binder resin and a colorant in an aqueous medium, and using the resulting emulsion as an organic solvent having the above-described means. The toner is supplied to a removal device and the organic solvent in the emulsion is removed to obtain toner particles. By defining the properties of the emulsion supplied to the device, a toner having good characteristics can be obtained, and the toner A toner production method capable of efficiently removing the organic solvent in the emulsion is obtained.

FIG. 1 shows an example of an apparatus for removing an organic solvent in an emulsion used in the present invention. An inner tube 2 for removing the solvent from the emulsion and an outer tube 2 outside the inner tube 2 are heated. The main part is comprised with the outer tube | pipe 1 for accommodating a medium and heating an inner tube | pipe. The upper and lower surfaces of the inner tube 2 and the outer tube 1 are hermetically sealed. Inside the inner tube 2, there is provided a rotor blade 4 that is fixed to the upper surface of the inner tube and has a length that extends further below the central portion of the inner tube. It has been. In the upper part of the outer tube 2, there is a raw material supply port 3 penetrating from the outside to the inner tube 2, from which an emulsion is supplied to the inner tube 2. Further, at the lower part of the inner pipe 2, on the same side as the raw material supply port 3, a residual liquid outlet 5 for taking out the remaining emulsified liquid consisting of a pipe connected to the inner pipe 2, and on the side opposite to the residual liquid outlet 5, In addition, a vapor outlet 6 for discharging the solvent vapor comprising a pipe connected to the inner pipe 2 is provided above the position of the residual liquid outlet 5.
Note that a partition plate 8 is preferably attached to the inner pipe 2 as shown in FIG. 1 in order to prevent the residual liquid of the emulsion from flowing out to the steam outlet 6.

  In order to remove the organic solvent in the emulsion using the above apparatus, the wall surface of the inner tube 2 is heated by the heat medium accommodated in the outer tube 1, the pressure is reduced by a vacuum pump, and the rotor blade 4 is An emulsion is supplied from the raw material inlet 3 into the rotating inner tube 2, and a thin film of the emulsion is formed on the wall surface of the inner tube 2 by centrifugal force. The inside of the inner tube 2 is heated to a temperature lower than the glass transition temperature of the toner. The organic solvent in the emulsion is controlled to be discharged from the vapor outlet 6 and the remaining emulsion is taken out from the residual liquid outlet 5.

  In the toner production method of the present invention, at least a binder resin and / or a binder resin precursor, a colorant, and a release agent are dissolved or dispersed in an organic solvent, and an oil phase composed of the solution or the dispersion is prepared. The emulsion is emulsified in an aqueous medium to obtain an emulsion. The removal efficiency of the organic solvent by the above apparatus is significantly affected by the physical properties of the emulsion. That is, the emulsion supplied to the apparatus needs to have a viscosity measurement value of 50 to 800 mPa · s at a rotation speed of a Brookfield viscometer at 25 ° C. of 50 to 800 mPa · s and an interfacial tension of 15 to 35 dyn / cm. is there. If it is less than 50 mPa · s, a thin film is not uniformly formed on the wall surface of the inner tube 2. On the other hand, if it exceeds 800 mPa · s, the film thickness increases, and the organic solvent removal efficiency deteriorates. Further, since a large amount of a surfactant is required to make the interfacial tension 15 dyn / cm or less, many steps are required for removing the surfactant, which is not economical. On the other hand, at 35 dyn / cm or more, as described above, the liquid film becomes thick and the organic solvent removal efficiency deteriorates.

  In the present invention, in order to examine the removal efficiency of the organic solvent, the ethyl acetate concentration in the emulsion before solvent removal (before supply) and the ethyl acetate concentration in the emulsion after solvent removal are measured.

In the present invention, the ethyl acetate concentration in the emulsion is determined by the following procedure.
[Measurement equipment conditions]
Measuring apparatus: GC-2010 (Shimadzu Gas Chromatograph)
Injection volume: 2.0 μL
Sample vaporization chamber Injection mode: Split Vaporization chamber temperature: 180 ° C
Carrier gas: He
Pressure: 40.2kPa
Total flow rate: 56.0 mL / min
Column flow rate: 1.04 mL / min
Linear velocity: 20.0 cm / sec
Purge flow rate: 3.0 mL / min
Split ratio: 50.0
Column Column name: ZB-50
Liquid phase film thickness: 0.25 μm
Length: 30.0mm
Inner diameter: 0.32 mm ID
Maximum column temperature: 340 ° C
Column oven Column temperature: 60 ° C
Column oven temperature program:
60 ° C hold 6 min → temperature rise rate 60 ° C / min → 230 ° C hold 5 min
Detector Detector temperature: 250 ° C
Make-up gas: N ₂ / Air
Makeup flow rate: 30.0 mL / min
H ₂ flow rate: 47.0 mL / min
Air flow rate: 400 mL / min
〔Measuring method〕
-Preparation of internal standard solution: Weigh 4 g of toluene in a volumetric flask and dilute to 500 mL with DMF.
-Preparation of measurement sample: After diluting 1.5 g of the emulsion to be measured to about 50 mL with DMF, 10 mL of the internal standard solution is collected and introduced with a whole pipette. After stirring the measurement sample with a stirrer at 400 rpm for 4 minutes, the sample is set in the autosampler of the measuring instrument GC and measurement is performed. After the measurement, the amount of ethyl acetate in the emulsion is calculated by the internal standard method from the ratio of toluene and ethyl acetate as the internal standard substance.

(Binder resin)
Next, as the binder resin in the toner production method of the present invention, a modified polyester resin, for example, a polymer having a site capable of reacting with a compound having an active hydrogen group is preferably used. In addition, a polyester resin that is not modified (unmodified polyester resin) is preferably used together with a polymer having a site capable of reacting with the compound having an active hydrogen group.

  The polymer having a site capable of reacting with the compound having an active hydrogen group used in the present invention is a binder resin component important for realizing low-temperature fixability and high-temperature offset resistance, and its weight average molecular weight is 3, 000-100,000 are preferred. That is, when the weight average molecular weight is less than 3,000, it becomes difficult to control the reaction rate, and problems in production stability begin to occur. On the other hand, when the weight average molecular weight exceeds 100,000, sufficient modified polyester cannot be obtained and the offset resistance starts to be affected.

  Examples of the polymer having a site capable of reacting with a compound having an active hydrogen group used in the present invention include a reactive modified polyester resin (RMPE) capable of reacting with active hydrogen, for example, a polyester prepolymer having an isocyanate group. (A) is mentioned. Examples of the prepolymer (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. In addition to the crosslinking agent for the modified polyester capable of reacting with active hydrogen, the amines described in detail below act as an extender.

  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 the compound (B6) obtained by blocking the amino group of B1 to B5 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). Usually 1.2 / 1 to 1 / 1.2. When [NCO] / [NHx] exceeds 1.2 / 1 or less than 1 / 1.2, the molecular weight of the polyester becomes low, and the hot offset resistance deteriorates.

  In the present invention, the modified polyester resin preferably used as the binder resin is a urea-modified polyester resin (UMPE), but the modified polyester resin may contain a urethane bond as well as a urea bond. The molar ratio of the urea bond content to the urethane bond content is usually 100/0 to 10/90, preferably 80/20 to 20/80, and more preferably 60/40 to 30/70. When the molar ratio of the urea bond is less than 10%, the hot offset resistance is deteriorated.

  Modified polyester resins such as urea-modified polyester resin (UMPE) are produced by a one-shot method or the like. The weight average molecular weight of the modified polyester resin such as urea-modified polyester resin (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 resin such as a urea-modified polyester resin is not particularly limited when using an unmodified polyester resin (PE), which will be described later, and is a number average that can be easily obtained to obtain the weight average molecular weight. Molecular weight is sufficient. In the case of a modified polyester resin such as UMPE alone, the number average molecular weight is usually from 3,000 to 100,000. When it exceeds 100,000, the low-temperature fixability and the gloss when used in a full-color apparatus are deteriorated.

  In the present invention, the modified polyester resin such as the polyester resin modified with urea bond (UMPE) is not only used alone, but also the polyester resin (PE) which is not modified is included as a binder resin component together with the modified polyester resin. You can also. The combined use of PE improves the low-temperature fixability and gloss when used in a full-color device, and is more preferable than using a modified polyester resin such as UMPE alone.

  Examples of PE include a polycondensate of polyol PO and polycarboxylic acid PC similar to the polyester resin component of UMPE, and preferable ones are also the same as those of 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 polyester resins 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. Therefore, the polyester resin component of UMPE and PE are preferably similar in composition. 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.

  PE (polyester resin) has an acid value of 1.0 to 50.0 (mgKOH / g), thereby controlling grain size by adding a base compound, low-temperature fixability, high-temperature offset resistance, heat-resistant storage stability, and charge stability. It is possible to make the toner characteristics such as higher quality. When the acid value exceeds 50.0 (mgKOH / g), the extension or crosslinking reaction of the modified polyester resin becomes insufficient, and the high temperature offset resistance is affected. When the acid value is less than 1.0 (mgKOH / g), This is because the dispersion stabilizing effect due to the base compound at the time of production cannot be obtained, and the modified polyester resin tends to elongate or undergo a crosslinking reaction, causing a problem in production stability.

In the present invention, the acid value of the polyester resin is measured by a method based on JIS K0070. However, when the sample does not dissolve, a solvent such as dioxane or THF is used as the solvent.
The acid value is specifically determined by the following procedure.

Measuring device: automatic potentiometric titrator (DL-53 Titrator, manufactured by METTLER TOLEDO)
Electrode used: DG113-SC (manufactured by METTLER TOLEDO)
Analysis software: LabX Light Version 1.00.000
Calibration of the apparatus: Use a mixed solvent of 120 ml of toluene and 30 ml of ethanol.
Measurement temperature: 23 ° C

The measurement conditions are as follows.
Stir
Speed [%] 25
Time [s] 15
EQP titration
Titrant / Sensor
Titrant CH ₃ ONa
Concentration [mol / L] 0.1
Sensor DG115
Unit of measurement mV
Predispensing to volume
Volume [mL] 1.0
Wait time [s] 0
Titrant addition Dynamic
dE (set) [mV] 8.0
dV (min) [mL] 0.03
dV (max) [mL] 0.5
Measure mode Equilibrium controlled
dE [mV] 0.5
dt [s] 1.0
t (min) [s] 2.0
t (max) [s] 20.0
Recognition
Threshold 100.0
Steepest jump only No
Range No
Tendency None
Termination
at maximum volume [mL] 10.0
at potential No
at slope No
after number EQPs Yes
n = 1
comb. termination conditions No
Evaluation
Procedure Standard
Potential 1 No
Potential 2 No
Stop for reevaluation No

(Measurement method of acid value)
Measurement is performed under the following conditions in accordance with the measurement method described in JIS K0070-1992. Sample preparation: 0.5 g of polyester (0.3 g for ethyl acetate-soluble component) is added to 120 ml of toluene and dissolved by stirring at room temperature (23 ° C.) for about 10 hours. Further, 30 ml of ethanol is added to prepare a sample solution. The measurement can be calculated by the apparatus described above, but specifically, the calculation is performed as follows. Titrate with a pre-standardized N / 10 caustic potash to alcohol solution, and determine the acid value from the consumption of the alcohol potash solution by the following calculation.
Acid value = KOH (ml) x N x 56.1 / sample weight (where N is a factor of N / 10 KOH)

  In the present invention, the heat-resistant storage performance of the main component of the polyester resin after modification, that is, the binder resin depends on the glass transition point of the polyester resin before modification, so that the glass transition point of the polyester resin is 35 ° C. to 65 ° C. It is preferable to design to. That is, if it is less than 35 ° C., the heat-resistant storage stability is insufficient, and if it exceeds 65 ° C., it adversely affects low-temperature fixing.

(Measurement method of glass transition point)
In the present invention, the glass transition point (Tg) is measured with a Rigaku THRMOFLEX TG8110 manufactured by Rigaku Corporation at a temperature increase rate of 10 ° C./min.
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 heating rate of 10 ° C./min, the sample was allowed to stand at 150 ° C. for 10 minutes, and the sample was cooled to room temperature and allowed to stand for 10 minutes. DSC measurement was performed by heating at / min. Tg was calculated from the tangent of the endothermic curve near the Tg and the base line using the analysis system in the TAS-100 system.

(Coloring agent)
Next, as the colorant in the toner production method of 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, Lead Red, Lead Red, Cadmium Red, Cadmium Mercury Red , Antimony vermilion, permanent red 4R, para red, Yisei Red, Parachlor Ortho Nitroaniline Red, Resol Fast Scarlet G, Brilliant Fast Scarlet, Brilliant Carmine BS, Permanent Red (F2R, F4R, FRL, FRLL, F4RH), Fast Scarlet VD, Belkan Fast Rubin B, Brilliant Scarlet G, Risor Rubin GX, Permanent Red F5R, Brilliant Carmine 6B, Pigment Scarlet 3B, Bordeaux 5B, Toluidine Maroon, Permanent Bordeaux F2K, Helio Bordeaux BL, Bordeaux 10B, Bon Maroon Light, Bon Maroon Medium, Eosin Lake, Rhodamine Lake B, Rhodamine Lake Y, Alizarin Lake, Thioindigo Red B, Thioindigo Maroon, Oil Red Quinacridone Red, Pyrazolone Red, Polyazo Red, Chrome 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, indanthrene blue (RS, BC), indigo, ultramarine, bitumen, anthraquinone blue, fast violet B, methyl violet lake, cobalt violet, manganese purple, dioxane violet, anthraquinone violet, chrome green, zinc green, chromium oxide, Pyridian, Emerald Green, Pigment Green B, Naphthol Green B, Green Gold, Acid Green Lakes, malachite green lakes, phthalocyanine greens, anthraquinone greens, titanium oxides, zinc whites, litbons 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

  The 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. In this case, an organic solvent can be used in order to enhance the interaction between the colorant and the resin. Also, 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.

(Release agent)
Next, a wax is preferably used as the release agent in the toner production method of the present invention. As the wax used in 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. As a result, the anti-offset effect is exhibited without applying a release agent 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, 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, chlorinated hydrocarbon, and poly n-stearyl methacrylate, 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.

  In the method for producing a toner of the present invention, a charge control agent may be included as a toner component 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 a phenol-based condensate (manufactured by Orient Chemical Industry Co., Ltd.), TP-302 of a quaternary ammonium salt molybdenum complex, TP-415 (manufactured by Hodogaya Chemical Industry 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, quinacridone Azo pigments, sulfonate group, carboxyl group, and polymer compounds having a functional group such as a quaternary ammonium salt.

  The amount of the 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, but is not uniquely limited. Preferably, it is 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. If the amount is less than 0.1 parts by weight, the effect of charge control is poor. If the amount exceeds 10 parts by weight, the chargeability of the toner is too high, reducing the effect of the main charge control agent, and electrostatic attraction with the developing roller. The force increases, leading to a decrease in developer fluidity and a decrease in image density. These charge control agents and 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.

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

  In 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 by weight 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 2000 parts by weight, it is not economical. Moreover, a dispersing agent can also be used as needed. It is preferable to use a dispersant because the particle size distribution becomes sharp and the dispersion is stable.

  Various dispersants are used for emulsifying and dispersing the oily phase in which the toner composition is dispersed in a 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.

  As a trade name, Surflon S-111, S-112, S-113 (above, Asahi Glass Co., Ltd.), Florard FC-93, FC-95, FC-98, FC-129 (above, made by Sumitomo 3M), Unidyne DS-101, DS-102 (above, manufactured by Daikin Industries), MegaFuck F-110, F-120, F-113, F-191, F-812, F-833 (above, Dainippon Ink Co., Ltd.) Manufactured), Xtop EF-102, 103, 104, 105, 112, 123A, 123B, 306A, 501, 201, 204 (above, manufactured by Tochem Products), Footent F-100, F150 (above, Neos) Manufactured).

Examples of cationic surfactants include aliphatic primary, secondary or secondary amine acids having a fluoroalkyl group, aliphatic quaternary ammonium salts such as perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salt, benza Luconium salt, benzethonium chloride, pyridinium salt, imidazolinium salt, trade names include Surflon S-121 (Asahi Glass), Florard FC-135 (Sumitomo 3M), Unidyne DS-202 (Daikin Industries) Megafac F-150, F-824 (manufactured by Dainippon Ink, Inc.), Xtop EF-132 (manufactured by Tochem Products), and Footgent F-300 (manufactured by Neos).
In addition, tricalcium phosphate, calcium carbonate, titanium oxide, colloidal silica, hydroxyapatite and the like can be used as an inorganic compound dispersant that is hardly soluble in water.

  Further, the same effect as that of the inorganic dispersant was confirmed for the resin fine particles. 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 (manufactured by Kao) SGP (manufactured by Soken)), Technopolymer SB (manufactured by Sekisui Plastics Co., Ltd. ), SGP-3G (manufactured by Soken), and Micropearl (manufactured by Sekisui Fine Chemical).

  In addition, as a dispersant that can be used in combination with the above inorganic dispersant and resin fine particles, the dispersed droplets may be stabilized by a polymeric 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 Vinyl acetate, pinyl propionate, vinyl butyrate, etc., acrylamide, methacrylamide, diacetone acrylamide or their methylol compounds, acid chlorides such as acrylic acid chloride, methacrylic acid chloride, vinyl pyridine, vinyl pyrrolidone, vinyl imidazole, ethylene imine, etc. Homopolymers or copolymers such as those having a nitrogen atom or a heterocyclic ring thereof, polyoxyethylene, polyoxypropylene, Oxyethylene alkylamine, polyoxypropylene alkylamine, polyoxyethylene alkylamide, polyoxypropylene alkylamide, polyoxyethylene nonyl phenyl ether, polyoxyethylene lauryl phenyl ether, polyoxyethylene stearyl phenyl ester, polyoxyethylene nonyl phenyl ester Polyoxyethylenes such as, celluloses such as methyl cellulose, hydroxyethyl cellulose, and hydroxypropyl cellulose can be used.

  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.

(Toner characteristics)
Next, characteristics of the toner manufactured according to the present invention will be described.
According to the study by the present inventors, it has been found that the acid value of the toner is a more important index than the acid value of the binder resin with respect to the low-temperature fixability and the high-temperature offset resistance. The toner acid value of the present invention is derived from the terminal carboxyl group of the unmodified polyester resin. The unmodified polyester resin preferably has an acid value of 0.5 to 40.0 (mg KOH / g) in order to control low-temperature fixability (fixing lower limit temperature, hot offset occurrence temperature, etc.) as a toner. . That is, when the toner acid value exceeds 40.0 (mgKOH / g), the modified polyester resin is insufficiently stretched or cross-linked, which affects the high-temperature offset resistance, and 0.5 (mgKOH / g). If the ratio is less than 1, the dispersion stabilizing effect due to the base compound at the time of production cannot be obtained, and the extension or crosslinking reaction of the modified polyester resin tends to proceed, causing a problem in production stability.
The method for measuring the acid value of the toner is the same as the method for measuring the acid value of the polyester resin described above, and is based on a method based on JIS K0070.

  In the present invention, the toner preferably has a volume average particle diameter Dv of 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 number of particles having a particle diameter of 2 μm or less exceeds 10% by number, it becomes a hindrance in the case where adhesion to a carrier or charging stability at a high level is achieved. 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.

  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.

  It is important that the toner of the present invention has an average circularity of 0.94 to 0.99, and an average circularity of less than 0.94 and an irregularly shaped toner that is too far from a sphere can achieve satisfactory transfer. High quality images with no characteristics or dust cannot be obtained. When the average circularity exceeds 0.99, in a system that employs blade cleaning or the like, a cleaning failure occurs on the photosensitive member and the transfer belt, causing stain on the image.

  Hereinafter, methods for measuring the particle diameter, circularity, and molecular weight of the toner of the present invention will be described.

(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 (manufactured by Nikka Giken Co., Ltd.) for outputting the number distribution and volume distribution and a PC 9801 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.

(Circularity and particles below 2 μm)
In the present invention, a flow type particle image analyzer (“FPIA-2100”; manufactured by Sysmex Corporation) is used to measure toner having a particle diameter of 2 μm or less, and analysis software (FPIA-2100 Data Processing Program for FPIA version 00- 10) was used for the analysis. Specifically, 0.1 to 0.5 ml of 10 wt% surfactant (alkylbenzene sulfonate Neogen SC-A; manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) is added to a glass 100 ml beaker, and each toner 0.1 0.5 g was added and stirred with microspatel, and then 80 ml of ion-exchanged water was added. The obtained dispersion was subjected to a dispersion treatment for 3 minutes with an ultrasonic disperser (manufactured by Honda Electronics Co., Ltd.). Using the FPIA-2100, the dispersion was measured for toner shape and distribution until a density of 5000 to 15000 / μl was obtained. In this measurement method, it is important that the concentration of the dispersion liquid is 5000 to 15000 / μl from the viewpoint of measurement reproducibility of the average circularity. In order to obtain the dispersion concentration, it is necessary to change the conditions of the dispersion, that is, the amount of surfactant to be added and the amount of toner. The amount of the surfactant varies depending on the hydrophobicity of the toner as in the measurement of the toner particle diameter described above. If it is added in a large amount, noise due to bubbles is generated. If the amount is too small, the toner cannot be sufficiently wetted. It becomes insufficient. Further, the toner addition amount differs from the particle size, and it is necessary to decrease the small particle size and increase the large particle size. When the toner particle size is 3 to 7 μm, the toner amount is 0.1 to 0. By adding 0.5 g, the dispersion concentration can be adjusted to 5000 to 15000 / μl.

(Molecular weight)
The molecular weight according to the present invention is measured by GPC (gel permeation chromatography) as follows. Stabilize the column in a heat chamber at 40 ° C., flow THF at a flow rate of 1 ml / min through the column at this temperature, and prepare a THF sample solution of resin prepared at a sample concentration of 0.05 to 0.6% by weight. Is measured by injecting 50 to 200 μl. In measuring the molecular weight of the sample, the molecular weight distribution of the sample was calculated from the relationship between the logarithmic value of the prepared calibration curve and the count using several types of monodisperse polystyrene standard samples. As a standard polystyrene sample for preparing a calibration curve, for example, Pressure Chemical Co. Alternatively, the molecular weights of Toyo Soda Kogyo Co., Ltd. are 6 × 10 ² , 2.1 × 10 ³ , 4 × 10 ³ , 1.75 × 10 ⁴ , 5.1 × 10 ⁴ , 1.1 × 10 ⁵ , 3.9. It is appropriate to use x10 ⁵ , 8.6 × 10 ⁵ , 2 × 10 ⁶ , 4.48 × 10 ⁶ , and use at least about 10 standard polystyrene samples. An RI (refractive index) detector is used as the detector.

(External additive)
To the toner base particles obtained in the present invention, an external additive can be used to assist fluidity, developability and chargeability. As this external additive, inorganic fine particles are preferably used. The primary particle diameter of the inorganic fine particles is preferably 5 mμ to 2 μm, and particularly preferably 5 mμ to 500 mμ. Moreover, it is preferable that the specific surface area by BET method is 20-500 m < ² > / g. The proportion of the inorganic fine particles used is preferably 0.01 to 5% by weight of the toner, and particularly preferably 0.01 to 2.0% by weight.

Specific examples of the inorganic fine particles include, for example, silica, alumina, titanium oxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate, zinc oxide, tin oxide, quartz sand, clay, mica, wollastonite, diatomaceous earth. Examples include soil, chromium oxide, cerium oxide, bengara, antimony trioxide, magnesium oxide, zirconium oxide, barium sulfate, barium carbonate, calcium carbonate, silicon carbide, and silicon nitride.
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 is performed using an average particle size of both fine particles 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 generate fireflies and the like can be obtained, and the residual toner can be further 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. Therefore, if the amount of titanium oxide fine particles added is larger than the amount of silica fine particles added, the effect of side effects is large. It is possible to become. 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.

(Two-component developer)
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 resins such as vinyl, polyester resins such as polyethylene terephthalate resin and polybutylene terephthalate resin, polycarbonate resins, polyethylene resins, polyvinyl fluoride resins, polyvinylidene fluoride resins, polytrifluoroethylene resins, polyhexafluoro Propylene resin, copolymer of vinylidene fluoride and acrylic monomer, copolymer of vinylidene fluoride and vinyl fluoride, tetrafluoroethylene and vinylidene fluoride And fluoro such as terpolymers of non-fluoride monomers including, and silicone resins. Moreover, you may 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.

(One-component developer)
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.

(Image forming method / apparatus)
The image forming method of the present invention uses the developer of the present invention and has at least an electrostatic latent image forming step, a developing step, a transferring step, and a fixing step, and other appropriately selected as required. You may further have a process, for example, a static elimination process, a cleaning process, a recycling process, a control process, etc.

  The image forming apparatus used in the present invention uses the developer of the present invention, and includes at least a photoconductor, a charging device, an exposure device, a developing device, a transfer device, and a fixing device. You may further have other means selected, for example, a static elimination apparatus, a cleaning apparatus, a recycling apparatus, a control apparatus, etc.

  The electrostatic latent image forming step is a step of forming an electrostatic latent image on the photoreceptor. The electrostatic latent image is formed, for example, by charging the surface of the photosensitive member uniformly by applying a voltage using a charging device and then exposing it like an image using an exposure device. Can do.

  The material, shape, structure, size and the like of the photoreceptor are not particularly limited and can be appropriately selected from known ones, but the shape is preferably a drum shape. Examples of the photoreceptor include inorganic photoreceptors such as amorphous silicon and selenium, and organic photoreceptors (OPC) such as polysilane and phthalopolymethine. Amorphous silicon photoreceptors are preferable in terms of long life. .

The charging device is not particularly limited and can be appropriately selected depending on the purpose. For example, a known contact charger including a conductive or semiconductive roll, brush, film, rubber blade, Examples thereof include a non-contact charger using corona discharge such as corotron and scorotron. The charging device is preferably arranged in contact or non-contact with the photoreceptor, and charges the surface of the photoreceptor by applying a DC voltage and an AC voltage in a superimposed manner.
The charging device is a charging roller that is disposed in close proximity to the photoconductor via a gap tape, and charges the surface of the photoconductor by applying a DC voltage and an AC voltage superimposed on the charging roller. Those that do are preferred.

  The exposure apparatus is not particularly limited as long as it can image-wise expose the surface of the photoreceptor charged by the charging apparatus, and can be appropriately selected according to the purpose. Examples thereof include a rod lens array system, a laser optical system, and a liquid crystal shutter optical system. In addition, you may employ | adopt the light back system which performs imagewise exposure from the back surface side of a photoreceptor.

  The developing step is a step of forming a visible image by developing the electrostatic latent image with the developer of the present invention using a developing device.

The developing device is not particularly limited as long as it can be developed using the developer of the present invention, and can be appropriately selected from known ones. For example, the developing device accommodates the developer of the present invention and is electrostatically charged. Examples include those having at least a developer-carrying body capable of applying a developer to a latent image in a contact or non-contact manner, and preferably including a developer-containing container in a detachable manner. The developing device may be either a dry developing method or a wet developing method, and may be either a single color developing device or a multicolor developing device. For example, the developer is charged by friction stirring. Examples include a stirrer and a rotatable magnet roller. In the developing device, for example, the toner and the carrier are mixed and stirred, and the toner is charged by friction at that time, and held on the surface of the rotating magnet roller in a raised state to form a magnetic brush. Since the magnet roller is disposed in the vicinity of the photoconductor, a part of the toner constituting the magnetic brush formed on the surface of the magnet roller moves to the surface of the photoconductor by an electric attractive force. As a result, the electrostatic latent image is developed with toner, and a visible image is formed on the surface of the photoreceptor. Note that an alternating electric field is preferably applied when the toner is moved to the surface of the photoreceptor.

  The transfer process is a process in which a visible image is transferred to a transfer target using a transfer device. After the primary transfer of the visible image onto the intermediate transfer member using the intermediate transfer member, the visible image is transferred to the transfer target. A mode in which secondary transfer is performed on a transfer body is preferred. In addition, a primary transfer step of forming a composite transfer image by transferring a visible image onto an intermediate transfer member using two or more colors, preferably full color toner, as the toner, and the composite transfer image on the transfer target An embodiment having a secondary transfer step of transferring is preferable. The visible image can be transferred by charging the photoconductor using, for example, a transfer charger.

  The transfer device preferably has a primary transfer device that transfers a visible image onto an intermediate transfer member to form a composite transfer image, and a secondary transfer device that transfers the composite transfer image onto a transfer target. The transfer device (primary transfer device, secondary transfer device) preferably has at least a transfer device that peels and charges the visible image formed on the photosensitive member toward the transfer target. There may be one transfer device or two or more transfer devices. Examples of the transfer device include a corona transfer device using corona discharge, a transfer belt, a transfer roller, a pressure transfer roller, and an adhesive transfer device.

  The intermediate transfer member is not particularly limited and can be appropriately selected from known transfer members according to the purpose. Examples thereof include a transfer belt.

  The transfer target is not particularly limited and can be appropriately selected from known recording media (recording paper).

  The fixing step is a step of fixing the visible image transferred to the transfer target using a fixing device, and may be fixed for each color toner each time it is transferred to the transfer target. The toners may be fixed simultaneously at the same time in a state where the toners are laminated.

  The fixing device is not particularly limited and may be appropriately selected according to the purpose. However, a fixing device that is heat-pressed and fixed using a known fixing member is preferable. The fixing member is preferably in the form of a roller or a belt, and examples thereof include a combination of a heating roller and a pressure roller, and a combination of a heating roller, a pressure roller and an endless belt. At this time, it is preferable that heating temperature is 80-200 degreeC normally.

  In the present invention, the fixing device includes a heating body having a heating element, a film in contact with the heating body, and a pressure member in pressure contact with the heating body through the film. It is possible to use means for heating and press-fixing by passing the transfer body on which the received image is formed.

  Depending on the purpose, for example, a known optical fixing device may be used together with the fixing device or instead of the fixing device.

  The neutralization step is a step of performing neutralization by applying a neutralization bias to the photoconductor using a neutralization device.

  The neutralization device is not particularly limited, and may be any one as long as it can apply a neutralization bias to the photosensitive member, and can be appropriately selected from known neutralization devices. Examples thereof include a neutralization lamp.

  The cleaning step is a step of removing toner remaining on the photoreceptor using a cleaning device.

  The cleaning device is not particularly limited as long as it can remove the toner remaining on the photoreceptor, and can be appropriately selected from known cleaners. For example, a magnetic brush cleaner, an electrostatic brush cleaner, a magnetic roller A cleaner, a blade cleaner, a brush cleaner, a web cleaner, etc. are mentioned.

  The recycling process is a process in which the toner removed in the cleaning process is recycled to the developing device using a recycling apparatus.

  There is no restriction | limiting in particular in a recycling apparatus, For example, a well-known conveyance means etc. are mentioned.

  A control process is a process of controlling each process using a control device.

  The control device is not particularly limited as long as the movement of each step can be controlled, and can be appropriately selected according to the purpose. Examples thereof include devices such as a sequencer and a computer.

  Next, the image forming method of the present invention will be described with reference to FIG. The image forming apparatus shown in FIG. 2 includes a photosensitive member 10, a charging device 20, an exposure device 30, a developing device 40, an intermediate transfer member 50, a cleaning device 60 having a cleaning blade, a charge eliminating device 70, a transfer device. A device 80 is provided. Note that a charging roller is used as the charging device 20, a static elimination lamp as the static elimination device 70, and a transfer roller as the transfer device 80.

The intermediate transfer member 50 is an endless belt, and is designed to be stretched by three support rollers 51 arranged on the inner side thereof so as to be movable in the arrow direction. A part of the three support rollers 51 also functions as a transfer bias roller capable of applying a predetermined transfer bias (primary transfer bias) to the intermediate transfer member 50. The intermediate transfer member 50 is provided with a cleaning device 90 having a cleaning blade in the vicinity thereof. Further, a transfer device 80 capable of applying a secondary transfer bias for transferring a visible image (secondary transfer) to the transfer target 95 is disposed opposite to the transfer device 80. Around the intermediate transfer member 50, a corona charger 58 for applying a charge to the visible image on the intermediate transfer member 50 is in contact with the photosensitive member 10 and the intermediate transfer member 50 in the rotation direction of the intermediate transfer member 50. And the contact portion between the intermediate transfer body 50 and the transfer body 95.
Note that transfer paper is used as the transfer target 95.

  The developing device 40 includes a developing belt 41 as a developer carrier, and a black developing unit 45K, a yellow developing unit 45Y, a magenta developing unit 45M, and a cyan developing unit 45C provided around the developing belt 41. ing. The developing unit 45K includes a developer accommodating portion 42K, a developer supplying roller 43K, and a developing roller 44K, and the developing unit 45Y includes a developer accommodating portion 42Y, a developer supplying roller 43Y, and a developing roller 44Y. The developing unit 45M includes a developer accommodating portion 42M, a developer supply roller 43M, and a developing roller 44M. The developing unit 45C includes a developer accommodating portion 42C, the developer supplying roller 43C, and the developing roller 44C. Yes. The developing belt 41 is an endless belt, is rotatably stretched around a plurality of belt rollers, and a part thereof is in contact with the photoconductor 10.

In this image forming apparatus, after the charging device 20 uniformly charges the photoconductor 10, the exposure device 30 performs imagewise exposure on the photoconductor 10 to form an electrostatic latent image. Next, the developing device 40 supplies the developer to the electrostatic latent image formed on the photoconductor 10 and develops it to form a visible image.
The visible image is transferred (primary transfer) onto the intermediate transfer body 50 by the voltage applied from the support roller 51 and further transferred (secondary transfer) onto the transfer body 95. As a result, a transfer image is formed on the transfer target 95. The toner remaining on the photoconductor 10 is removed by the cleaning device 60, and the charge of the photoconductor 10 is removed by the charge eliminating lamp 70.

Next, another aspect of the image forming method of the present invention will be described with reference to FIG. The image forming apparatus shown in FIG. 3 has a black developing unit 45K, a yellow developing unit 45Y, a magenta developing unit 45M, and a cyan around the photosensitive member 10, instead of the developing device 40 in the image forming apparatus shown in FIG. The developing unit 45C has the same configuration as that of the image forming apparatus shown in FIG.
In FIG. 3, the same components as those of the image forming apparatus shown in FIG. The same applies to FIGS. 4 and 5 described later.

  Next, another aspect of the image forming method of the present invention will be described with reference to FIG. The image forming apparatus shown in FIG. 4 is a tandem type color image forming apparatus. The image forming apparatus includes a copying apparatus main body 150, a paper feed table 200, a scanner 300, and an automatic document feeder (ADF) 400.

  The copying apparatus main body 150 is provided with an endless belt-like intermediate transfer member 50 at the center. The intermediate transfer member 50 is stretched around the support rollers 14, 15, and 16 and can rotate clockwise in FIG. 4. A cleaning device 17 for removing residual toner on the intermediate transfer member 50 is disposed in the vicinity of the support roller 15. On the intermediate transfer member 50 stretched by the support roller 14 and the support roller 15, four image forming units 18 of yellow, cyan, magenta, and black are arranged opposite to each other along the conveying direction. A means 120 is arranged. An exposure device 21 is disposed in the vicinity of the image forming unit 120. The secondary transfer device 22 is disposed on the side of the intermediate transfer member 50 opposite to the side on which the image forming unit 120 is disposed. In the secondary transfer device 22, a secondary transfer belt 24, which is an endless belt, is stretched around a pair of support rollers 23, and the recording paper conveyed on the secondary transfer belt 24 and the intermediate transfer member 50 are mutually connected. It is possible to touch. A fixing device 25 is disposed in the vicinity of the secondary transfer device 22. The fixing device 25 includes a fixing belt 26 that is an endless belt and a pressure roller 27 that is pressed against the fixing belt 26. A reversing device 28 for reversing the recording paper is disposed in the vicinity of the secondary transfer device 22 and the fixing device 25 in order to form images on both sides of the recording paper.

  Next, formation of a full-color image (color copy) using the image forming unit 120 will be described. First, an original document is set on the document table 130 of the automatic document feeder (ADF) 400 or the automatic document feeder 400 is opened, and the original document is set on the contact glass 32 of the scanner 300. Close.

  When a start switch (not shown) is pressed, when the document is set on the automatic document feeder 400, the document is transported and moved onto the contact glass 32, and then the document is set on the contact glass 32. When this happens, the scanner 300 is immediately driven, and the first traveling body 33 and the second traveling body 34 travel. At this time, light from the light source is irradiated by the first traveling body 33, and reflected light from the document surface is reflected by a mirror in the second traveling body 34. Further, the image is received by the reading sensor 36 through the imaging lens 35, and the original is read to obtain image information of black, yellow, magenta and cyan. Next, each image information is transmitted to each image forming unit 18 in the image forming means 120, and a visible image of each color of black, yellow, magenta and cyan is formed.

  As shown in FIG. 5, the image forming unit 18 includes a photoconductor 10, a charging device (unsigned) for uniformly charging the photoconductor 10, and an exposure device 21 based on the image information. The electrostatic latent image formed by exposing the photosensitive member 10 to the toner is developed with each toner (black toner, yellow toner, magenta toner, and cyan toner) to form a visible image with each toner. It includes a device (no code), a transfer charger (no code) for transferring a visible image onto the intermediate transfer member 50, a cleaning device (no code), and a charge eliminating device (no code). Based on this, it is possible to form a visible image of each color. Next, the visible images of the respective colors are sequentially transferred (primary transfer) onto the intermediate transfer body 50 that is rotated and moved by the support rollers 14, 15 and 16, and the visible images of the respective colors are superimposed to form a composite transfer image. It is formed.

  On the other hand, in the paper feed table 200, one of the paper feed rollers 142 is selectively rotated to feed the recording paper from one of the paper feed cassettes 144 provided in multiple stages in the paper bank 143, and one sheet at a time by the separation roller 145. The paper is separated and sent to the paper feed path 146, transported by the transport roller 147, guided to the paper feed path 148 in the copying machine main body 150, and abutted against the registration roller 49 to stop. Alternatively, the paper feed roller 142 is rotated to feed out the recording paper on the manual feed tray 54, separated one by one by the separation roller 52, put into the manual paper feed path 53, and abutted against the registration roller 49 and stopped. The registration roller 49 is generally used while being grounded, but may be used in a state where a bias is applied to remove paper dust from the recording paper. Then, the registration roller 49 is rotated in synchronization with the composite transfer image formed on the intermediate transfer member 50, and the recording paper is sent between the intermediate transfer member 50 and the secondary transfer device 22, so that the secondary transfer device. By transferring the composite transfer image onto the recording paper (secondary transfer) by 22, a color image is formed on the recording paper. The toner remaining on the intermediate transfer member 50 is removed by the cleaning device 17.

  The recording paper on which the color image is formed is conveyed by the secondary transfer device 22 and sent to the fixing device 25, where the composite transfer image is heated and pressed and fixed on the recording paper. Thereafter, the recording paper is switched by the switching claw 55 and discharged by the discharge roller 56 and is stacked on the discharge tray 57. Alternatively, it is switched by the switching claw 55 and reversed by the reversing device 28 and led to the transfer position again. After an image is formed also on the back surface, the sheet is discharged by the discharge roller 56 and stacked on the discharge tray 57.

(Process cartridge)
The process cartridge of the present invention includes a latent image carrier on which an electrostatic latent image is formed, and a developing device that develops the electrostatic latent image formed on the latent image carrier using the developer of the present invention. It is supported at least integrally and is detachable from the main body of the image forming apparatus. The process cartridge of the present invention may further support other means appropriately selected as needed.

  FIG. 6 shows an example of the process cartridge of the present invention. The process cartridge includes a photoreceptor 10 and includes a charging device 20, an exposure device 30, a developing device 40, a cleaning device 60, and a transfer device 80. These members can be the same as those used in the image forming apparatus described later.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further, this invention is not limited to this. “Parts” indicates parts by weight, and “%” indicates% by weight.

Measuring method:
(Acid value (mgKOH / g))
It was measured by the method described above.

(Residual solvent amount in emulsion after organic solvent removal)
It was measured by the method described above.

(Glass transition point Tg (℃))
It was measured by the method described above.

Production Example 1
(Production of resin fine particle dispersion)
In a reaction vessel equipped with a stirrer and a thermometer, 683 parts of water, 11 parts of sodium salt of ethylene oxide methacrylate adduct sulfate (Eleminol RS-30, Sanyo Chemical Industries), 83 parts of styrene, 83 parts of methacrylic acid Then, 110 parts of butyl acrylate and 1 part of ammonium persulfate were charged and stirred at 400 rpm for 15 minutes, whereby a white emulsion was obtained. The system was heated to raise the system temperature to 75 ° C. and reacted for 5 hours. Further, 30 parts of a 1% ammonium persulfate aqueous solution was added, and the mixture was aged at 75 ° C. for 5 hours, and an aqueous vinyl resin (a copolymer of styrene-methacrylic acid-butyl acrylate-methacrylic acid ethylene oxide adduct sulfate sodium salt). A dispersion [resin fine particle dispersion 1] was obtained. The volume average particle diameter of [resin fine particle dispersion 1] measured with LA-920 was 105 nm. A portion of [resin fine particle dispersion 1] was dried to isolate the resin component. The resin content had a Tg of 59 ° C. and a weight average molecular weight of 150,000.

(Preparation of aqueous phase)
990 parts of water, 83 parts of [resin fine particle dispersion 1], 37 parts of 48.5% by weight aqueous solution of sodium dodecyl diphenyl ether disulfonate (Eleminol MON-7: manufactured by Sanyo Chemical Industries) and 90 parts of ethyl acetate are mixed and stirred. As a result, a milky white aqueous medium was obtained.

(Production of low molecular weight polyester-1)
229 parts of bisphenol A ethylene oxide 2-mole adduct, 529 parts of bisphenol A propion oxide 3-mole adduct, 208 parts of terephthalic acid, 46 parts of isophthalic acid, and dibutyl 2 parts of tin oxide was added and reacted at 230 ° C. for 5 hours under normal pressure. Next, the reaction solution was reacted for 5 hours under a reduced pressure of 10 to 15 mmHg, and then 44 parts of trimellitic anhydride was added to the reaction vessel and reacted at 180 ° C. for 2 hours under normal pressure. Molecular polyester-1] was synthesized. The obtained [low molecular weight polyester-1] had a weight-average molecular weight (Mw) of 5,200, a glass transition temperature (Tg) of 45 ° C., and an acid value of 20 mgKOH / g.

(Prepolymer production)
Synthesis of intermediate polyester 463 parts of propylene glycol, 657 parts of terephthalic acid, 96 parts of trimellitic anhydride and 2 parts of titanium tetrabutoxide are placed in a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen introduction tube at normal pressure. The mixture was reacted at 230 ° C. for 8 hours, and further reacted at a reduced pressure of 10 to 15 mmHg for 5 hours to obtain [Intermediate Polyester 1]. [Intermediate Polyester 1] had a weight average molecular weight of 28000, Tg of 36 ° C., an acid value of 0.5 mgKOH / g, and a hydroxyl value of 16.5 mgKOH / g.
Next, 250 parts of [Intermediate polyester 1], 16.7 parts of isophorone diisocyanate, and 250 parts of ethyl acetate are placed in a reaction vessel equipped with a cooling pipe, a stirrer, and a nitrogen introduction pipe, and reacted at 100 ° C. for 5 hours. Polymer 1] was obtained. The isocyanate of [Prepolymer 1] was 0.52%.

(Production of master batch (MB))
In a reaction vessel equipped with a condenser, a stirrer and a nitrogen introduction tube, 319 parts of bisphenol A propylene oxide 2-mole adduct: 449 parts, 449 parts of bisphenol A ethylene oxide 2-mole adduct, 243 parts of terephthalic acid, adipic acid: 53 parts and dibutyltin oxide: 2 parts were added, reacted at normal pressure and 230 ° C. for 8 hours, further reacted at a reduced pressure of 10 to 15 mmHg for 5 hours, and then put 7 parts of trimellitic anhydride into the reaction vessel. Reaction was performed at 180 ° C. and normal pressure for 2 hours to obtain [Polyester for MB]. [Polyester for MB] had a number average molecular weight of 1900, a mass average molecular weight of 6100, a Tg of 43 ° C., and an acid value of 1.1 mgKOH / g.
Water: 30 parts, C.I. I. Pigmrnt Red 122 (Magenta R: manufactured by Toyo Ink Co., Ltd.): 40 parts, [MB polyester]: 60 parts are added, mixed with a Henschel mixer (Mitsui Mining Co., Ltd.), and the mixture in which water is soaked into the pigment aggregate is obtained. Obtained. The mixture was kneaded at 130 ° C. for 45 minutes using two rolls, rolled and cooled, and pulverized with a pulverizer to obtain a [masterbatch].

(Production of oil phase)
In a container equipped with a stirrer and a thermometer, 378 parts of [Low molecular weight polyester-1], 110 parts of Carnauba WAX, 22 parts of a charge control agent (salicylic acid metal complex E-84: manufactured by Orient Chemical Industries), 947 parts of ethyl acetate. The mixture was charged, heated to 80 ° C. with stirring, held at 80 ° C. for 5 hours, and then cooled to 30 ° C. over 1 hour. Next, 500 parts of [Masterbatch] and 500 parts of ethyl acetate were charged in a container and mixed for 1 hour to obtain [Raw material solution 1].
[Raw material solution 1] 1324 parts are transferred to a container and filled with 80% by volume of 0.5 mm zirconia beads using a bead mill (Ultra Visco Mill, manufactured by Imex) with a liquid feed rate of 1 kg / hr, a disk peripheral speed of 6 m / sec. Carbon black and WAX were dispersed under the condition of 3 passes. Next, 1324 parts of a 65% ethyl acetate solution of [low molecular weight polyester 1] was added, and one pass was performed with a bead mill under the above conditions to obtain [Pigment / WAX Dispersion 1]. The solid content concentration of [Pigment / WAX Dispersion 1] (130 ° C., 30 minutes) was 50%.

[Example 1]
[Pigment / WAX Dispersion 1] 749 parts and [Prepolymer 1] 115 parts were put in a container, mixed with TK homomixer (manufactured by Tokushu Kika Co., Ltd.) at 5000 rpm for 1 minute, and then [Water Phase 1] 1200 After mixing with a TK homomixer for 20 minutes with TK homomixer, 1.4% of carboxymethylcellulose was added to obtain [Emulsion slurry 1]. The amount of ethyl acetate in the emulsion was 20% with respect to 100 parts of the emulsion. The viscosity measurement value of the Brookfield viscometer at a rotation speed of 60 rpm was 310 mPa · sec.
10 kg of the emulsified liquid is supplied to the inner pipe of the apparatus shown in FIG. 1 having an inner pipe wall temperature of 50 ° C., an inner pipe inner pressure of 75 mmHg, and an inner pipe heat transfer area of 0.3 m ² at a feed rate of 3 kg / min. Was discharged, and the remaining liquid of the emulsion was taken out. After removing the organic solvent, the slurry (the above residual liquid) is put in a jacketed 20 L tank, aged at a jacket hot water temperature of 45 ° C., filtered, washed, dried, then air-classified, and spherical toner base particles Got.
100 parts of the obtained toner base particles and 0.25 part of a charge control agent (Bontron E-84 manufactured by Orient Chemical Co., Ltd.) were charged into a Q-type mixer (Mitsui Mining Co., Ltd.), and the peripheral speed of the turbine blades was adjusted to 50 m / sec. Set and mixed. In this case, the mixing operation was performed for 2 minutes, 5 minutes of 1 minute pause, and the total treatment time was 10 minutes. Further, 0.5 part of hydrophobic silica (H2000, manufactured by Clariant Japan) was added and mixed. In this case, the mixing operation was performed at a peripheral speed of 15 m / second, and 30 seconds of mixing and resting for 1 minute were performed for 5 cycles to obtain final [Toner 1].

[Example 2]
The same procedure as in Example 1 was carried out except that 0.01% of a surfactant manufactured by Neos: FT gent-FT-300 was added to the emulsion, and the steps after removal of the organic solvent were carried out as [Toner 1 The final [Toner 2] was obtained in the same manner as above.

Example 3
The same procedure as in Example 1 was carried out except that 0.1% of surfactant surfactant FT-310 manufactured by Neos Co. was added to the emulsion, and the step after removing the organic solvent was performed as [Toner The final [Toner 3] was obtained in the same manner as in [1].

Example 4
Except for adding 0.3% of carboxymethyl cellulose to the emulsion, the same operation as in Example 1 was performed, and the process after removing the organic solvent was performed in the same manner as in [Toner 1]. [Toner 4] was obtained.

Example 5
Example 1 except that 100 parts of the emulsion was filtered under reduced pressure, 100 parts of ethyl acetate saturated ion-exchanged water was added to the filter cake, and the mixture was mixed with a TK homomixer (rotation speed: 12000 rpm for 10 minutes). The same operation was performed to remove the organic solvent, and the same process as [Toner 1] was performed to obtain the final [Toner 5].

Example 6
100 parts of the emulsion was filtered under reduced pressure, 100 parts of ethyl acetate saturated ion exchange water and 1.4% of carboxymethyl cellulose were added to the filter cake, and the mixture was mixed with a TK homomixer (rotation speed: 12,000 rpm for 10 minutes). The same operation as in Example 1 was carried out except that it was used, and the process after removing the organic solvent was carried out in the same manner as in [Toner 1] to obtain the final [Toner 6].

Example 7
The process after removing the organic solvent was carried out in the same manner as in Example 1 except that 1% of Neosurf's surfactant: FT FT-310 was added to the emulsion. The final [Toner 7] was obtained in the same manner as above.

[Comparative Example 1]
Except for adding 1.5% of carboxymethylcellulose to the emulsion, the same operation as in Example 1 was performed, and the steps after removing the organic solvent were performed in the same manner as in [Toner 1]. [Toner 8] was obtained.

[Comparative Example 2]
100 parts of the emulsion was filtered under reduced pressure, 100 parts of ethyl acetate saturated ion-exchanged water was added to the filter cake, and the mixture was mixed with a stirrer (10 minutes at 500 rpm) for 3 times. The same operation as in Example 1 was performed, and the process after removing the organic solvent was performed in the same manner as in [Toner 1] to obtain the final [Toner 9].

  The physical properties (viscosity, interfacial tension, ethyl acetate concentration in the emulsion, and ethyl acetate concentration in the emulsion after removal of the solvent) of the emulsions in the above Examples and Comparative Examples were measured. Further, the physical properties (particle size distribution, circularity, acid value, glass transition point) of the obtained toner and the performance (charge amount, minimum fixing temperature and maximum temperature, storage stability, image quality) of the toner were evaluated. Table 1 shows the physical properties of the emulsion, Table 2 shows the properties of the obtained toner, and Table 2 shows the performance of the toner.

Measuring method:
The particle size distribution, circularity, acid value, and glass transition point were measured by the methods described above. A method for evaluating the charge amount, fixing temperature, storage stability, and image quality is shown below.

(Charge amount)
1) Charge amount for 15 seconds stirring Charge 10 g of each toner and 100 g of ferrite carrier in a stainless steel pot up to 30% of the internal volume in an environment with a temperature of 28 ° C. and a humidity of 80%, and stir for 15 seconds at a stirring speed of 100 rpm. Then, the charge amount (μC / g) of the developer was measured with [Toshiba Chemical Co., Ltd .: TB-200].
The charge amount of the toner was measured by the blow-off method.
2) Charge amount for 10 minutes stirring Charge amount measurement by the blow-off method for charge amounts (1) and (2) when stirred for 10 minutes in the same manner as 1) was performed as follows.
In a test room with a temperature of 20 ° C. and a humidity of 50%, 10 g of each toner and 100 g of ferrite carrier are placed in a stainless steel pot up to 30% of the internal volume, and stirred for 10 minutes at a stirring speed of 100 rpm. g) was measured by [Toshiba Chemical Co., Ltd .: TB-200].

(Fixability evaluation)
Using a device in which a fixing unit of a Ricoh copier (MF2200) using a Teflon (registered trademark) roller as a fixing roller was modified, type 6200 paper manufactured by Ricoh was set in this and a copying test was performed. The cold offset temperature (fixing lower limit temperature) and the hot offset temperature (hot offset resistant temperature) were determined by changing the fixing temperature. The minimum fixing temperature of the conventional low-temperature fixing toner is about 140 to 150 ° C. The evaluation conditions for low-temperature fixing are as follows: the paper feed linear speed is 120 to 150 mm / sec, the surface pressure is 1.2 kgf / cm ² , the nip width is 3 mm, and the high temperature offset is the paper feed linear speed of 50 mm / sec. The contact pressure was set to 2.0 kgf / cm ² and the nip width was 4.5 mm.

(Heat resistant storage stability)
After the toner was stored at 50 ° C. for 8 hours, it was sieved with a 42 mesh sieve for 2 minutes, and the residual ratio on the wire mesh was regarded as 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 Δ: 20-30%
○: 10 to 20%
A: Less than 10%

(Image density)
Using a digital full-color copier (imageColor 2800, manufactured by Ricoh Co., Ltd.), after running 150,000 image charts with a 50% image area in single color mode, a solid image was output to 6000 paper manufactured by Ricoh Co., and the image density was set to XRite. Measurement was carried out by (manufactured by X-Rite).
This was performed for four colors alone, and the average was obtained. When this value is less than 1.2, “x”, when it is 1.2 or more and less than 1.4, “△”, when it is 1.4 or more and less than 1.8, “◯”, 1.8 or more and 2 If less than 2, “◎” was assigned.

(Image graininess, sharpness)
Using a digital full-color copying machine (imageColor 2800, manufactured by Ricoh), a photographic image was output in a single color, and the degree of graininess and sharpness was visually evaluated. In order from the best, “◎” is equivalent to offset printing, “○” is slightly worse than offset printing, “△” is much worse than offset printing, “×” is about the same as conventional electrophotographic images (very much Bad).

(Dirt)
Using a digital full-color copier (ImagioColor 2800, manufactured by Ricoh Co., Ltd.), running 30,000 image charts with a 50% image area in single-color mode, then stopping the blank image during development, and developing on the photoreceptor after development The agent was transferred to tape, and the difference from the image density of the untransferred tape was measured with a 938 spectrodensitometer (manufactured by X-Rite). The smaller the difference in image density, the better the background dirt. From the best ones, “◎”, “○”,
Ranking was in the order of “△” and “×”.

  From Tables 1 to 3, according to the examples, the organic solvent in the emulsion is efficiently removed by adjusting the viscosity and interfacial tension of the emulsion before introduction of the organic solvent removing apparatus to a specific range. In addition, it can be seen that a toner having both low-temperature fixability and charging stability can be obtained.

DESCRIPTION OF SYMBOLS 1 Outer pipe 2 Inner pipe 3 Raw material inlet 4 Rotor blade 5 Residual liquid outlet 6 Steam outlet 8 Partition plate 10 Photoconductor (photosensitive drum)
10K black photoconductor 10Y yellow photoconductor 10M magenta photoconductor 10C cyan photoconductor 14 support roller 15 support roller 16 support roller 17 intermediate transfer cleaning device 18 image forming means 20 charging roller 21 exposure device 22 secondary transfer device 23 Roller 24 Secondary transfer belt 25 Fixing device 26 Fixing belt 27 Pressure roller 28 Sheet reversing device 30 Exposure device 32 Contact glass 33 First traveling member 34 Second traveling member 35 Imaging lens 36 Reading sensor 40 Developing device 41 Developing belt 42K Developer container 42Y Developer container 42M Developer container 42C Developer container 43K Developer supply roller 43Y Developer supply roller 43M Developer supply roller 43C Developer supply roller 44K Developer roller 44Y Developer roller 44M Developer Roller 44C Developing roller 45K Black developing unit 45Y Yellow developing unit 45M Magenta developing unit 45C Cyan developing unit 49 Registration roller 50 Intermediate transfer member 51 Roller 52 Separating roller 53 Manual feed path 54 Manual feed tray 55 Switching claw 56 Discharge roller 57 discharge tray 58 corona charger 60 cleaning device 61 developing device 62 transfer charger 63 photoconductor cleaning device 64 discharger 70 discharger lamp 80 transfer roller 90 cleaning device 95 transfer paper 100 image forming device 101 photoconductor 102 charging means 103 exposure 104 Developing means 105 Recording medium 107 Cleaning means 108 Transfer means 120 Tandem developer 130 Document table 142 Paper feed roller 143 Paper bank 144 Paper feed cassette 145 Separating roller 14 Feeding path 147 transport rollers 148 feed path 150 copier main body 200 feeder table 300 Scanner 400 automatic document feeder (ADF)

Japanese Patent Laid-Open No. 11-133665 JP 9-15903 A Japanese Patent No. 3154073 JP-A-11-149179 Japanese Patent No. 4030937

Claims (6)

In an organic solvent, at least a binder resin and / or a binder resin precursor, a colorant, and a release agent are dissolved or dispersed, and an oil phase composed of the solution or dispersion is emulsified in an aqueous medium. A toner manufacturing method for obtaining toner base particles by granulating and removing an organic solvent from the emulsion,
In the step of removing the organic solvent from the emulsion, the inner tube wall surface is heated by a heat medium in the outer tube using an apparatus including the following means (a) to (d), and the pressure is reduced by a vacuum pump: In addition, the emulsion is supplied into the inner tube in which the rotor blades are rotated to form a thin film of the emulsion on the inner wall of the inner tube by centrifugal force, and the inside of the inner tube is controlled below the glass transition temperature of the toner. Draining the organic solvent in the emulsion and taking out the remaining emulsion,
The emulsion to be supplied to the step has a viscosity measurement value of 50 to 800 mPa · s at 25 ° C. and a Brookfield viscometer rotation speed of 60 rpm, and the emulsion has an interfacial tension of 15 to 35 dyn / cm.
A method for producing a toner for developing an electrostatic charge image.
(A) an inner tube for removing the organic solvent in the emulsion, and an outer tube outside the inner tube for containing the heat medium and heating the inner tube,
(B) The upper and lower surfaces of the inner tube and the outer tube are sealed, and the inner tube has a rotating blade fixed to the upper surface of the inner tube and reaching further below the central portion of the inner tube,
(C) The upper portion of the outer pipe has a raw material supply port penetrating from the outside to the inner pipe,
(D) at the lower part of the inner pipe, on the same side as the supply port, a residual liquid outlet for taking out the remaining emulsion consisting of a pipe connected to the inner pipe, on the side opposite to the residual liquid outlet, and Above the position of the residual liquid outlet, a vapor outlet for discharging the solvent vapor consisting of a pipe connected to the inner pipe is provided.   The oil phase contains at least a polymer having a site capable of reacting with a compound having an active hydrogen group, a binder resin, a colorant, and a release agent, and the oil phase is dispersed in an aqueous medium containing resin fine particles, The electrostatic charge image developing toner according to claim 1, wherein the toner base particles are obtained by removing the organic solvent after reacting the polymer having a site capable of reacting with the compound having an active hydrogen group or while reacting the polymer. Toner manufacturing method.   The method for producing a toner for developing an electrostatic charge image according to claim 1, wherein the binder resin contains a polyester resin.   The method for producing a toner for developing an electrostatic charge image according to claim 3, wherein the polyester resin has an acid value of 1.0 to 50.0 (mgKOH / g).   The method for producing a toner for developing an electrostatic charge image according to claim 3 or 4, wherein the polyester resin has a glass transition point of 35 to 65 ° C. 3. The method for producing a toner for developing an electrostatic charge image according to claim 2, wherein the polymer having a site capable of reacting with the compound having an active hydrogen group has a weight average molecular weight of 3,000 to 100,000. .

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