JP4632447B2 - Toner manufacturing method and toner - Google Patents

Description

  The present invention relates to a toner manufacturing method and a toner manufactured by the method. More specifically, the present invention can prevent the occurrence of filming, sleeve fixing, etc., and can be used for low-temperature fixability, hot offset resistance, and heat storage stability. The present invention relates to a toner manufacturing method suitable for a fixing device that can achieve an energy saving level that is excellent and unprecedented, and a toner manufactured by the method.

  In the developing process, a developer used in electrophotography, electrostatic recording, electrostatic printing, and the like is once attached to an image carrier such as a photoreceptor on which an electrostatic charge image is formed, and then transferred to a transfer process. After being transferred from the photoconductor to a transfer medium such as transfer paper, the toner is fixed on the paper surface in a fixing step. At that time, as a developer for developing an electrostatic charge image formed on the latent image holding surface, a two-component developer composed of a carrier and a toner and a one-component developer that does not require a carrier (magnetic toner, non-magnetic toner) Magnetic toner) is known. Conventionally, as toner used for electrophotography, electrostatic recording, electrostatic printing, etc., a binder resin (binder) such as a styrene resin or polyester is melt-kneaded with a colorant or the like and finely pulverized. Yes.

These toners are developed and transferred onto paper or the like, and then fixed by heating and melting using a hot roll. At that time, if the hot roll temperature is too high, a problem (hot offset) in which the toner is excessively melted and fused to the hot roll occurs. On the other hand, if the heat roll temperature is too low, the toner will not be sufficiently melted, resulting in insufficient fixing. From the viewpoint of energy saving and downsizing of apparatuses such as copying machines, a toner having a higher hot offset generation temperature (hot offset resistance) and a lower fixing temperature (low temperature fixing property) is required.
In particular, full-color copiers and full-color printers require gloss and color mixing of their images, so the toner needs to have a lower melt viscosity, and sharp-melt polyester binders are used. ing. In such a toner, since hot offset is likely to occur, conventionally, in a full-color device, silicone oil or the like is applied to a heat roll. However, the method of applying silicone oil to the hot roll requires an oil tank and an oil application device, which complicates and enlarges the device. Moreover, it also causes deterioration of the heat roll, requiring maintenance at regular intervals. Furthermore, it is inevitable that oil adheres to copy paper, OHP (overhead projector) film, and the like, especially in OHP, deterioration of color tone due to the adhered oil becomes a problem.

  Therefore, a method of adding a release agent to the toner is generally used in order to prevent the toner from fusing without applying oil to the hot roll. The dispersion state at has a great influence. When the release agent is compatible with the binder, the release property cannot be expressed, and the release property can be improved only when it exists as incompatible domain particles. If the dispersion diameter of the domain particles is too large, the ratio of the release agent present in the vicinity of the toner particle surface is relatively increased, so that the agglomeration is exhibited and the fluidity is deteriorated. There is a problem that the film is transferred to a carrier or a photoconductor to cause filming to prevent obtaining a good image quality. In addition, the color toner has a problem that the color reproducibility and transparency are impaired. On the other hand, if the dispersion diameter is too small, the release agent is excessively finely dispersed and sufficient releasability cannot be obtained. Although the control of the dispersion diameter of the release agent is indispensable as described above, an appropriate method has not yet been found.

  In the case of a toner produced by a pulverization method, the major factor that determines the dispersion diameter is the shearing force of kneading at the time of melt-kneading. In recent years, polyester resins that are frequently used in toner binders have low viscosity. Therefore, it was very difficult to control the dispersion of the mold release agent because a sufficient shearing force was not applied, and it was difficult to obtain an appropriate dispersion diameter. In addition, another problem in the pulverization method is that the release agent is likely to have a fracture surface, so that the release agent exposed to the surface increases.

  On the other hand, in recent years, polymerized toners have been developed and commercialized, and polymerized toners have the advantage that a toner having a small particle size is easy to produce, and thus high image quality is obtained, and fluidity and transferability are good. For example, toner particles are obtained by a suspension polymerization method (see, for example, Patent Document 1). However, in the conventional suspension polymerization method, when a low melting point mold release agent is used, when the release agent is dispersed in the monomer, if a large stirring share is applied, the mixed monomer-release agent dispersion is filled. A local temperature rise occurs in a part of the stirring tank, especially in the vicinity of the stirring means, the low-melting-point release agent melts, the release agent bleeds out on the surface, and particles consisting only of the release agent are generated. There is a drawback that it will. In addition, due to the heat during the polymerization, the release agent may be similarly melted to produce particles composed only of the release agent.

  In addition, a method has been proposed in which resin fine particles obtained by an emulsion polymerization method are associated to obtain amorphous toner particles (see, for example, Patent Document 2). However, in the conventional emulsion polymerization method, resin fine particles, release agent fine particles, colorant fine particles and the like dispersed in water are heated and aggregated to form associated toner particles, but a low melting point release agent is used as the release agent particles. In this case, when a large stirring share is applied when dispersing the release agent in water, a local temperature rise occurs in a part of the stirring tank filled with the mixed release agent dispersion, particularly in the vicinity of the stirring means. As a result, the low-melting-point release agent melts, and the release agent bleeds out on the surface, so that particles composed of only the release agent may be generated. Moreover, the heat | fever at the time of carrying out heat aggregation may fuse | melt a mold release agent similarly, and may produce | generate the particle | grains which consist only of mold release agents.

Recently, although not strictly the conventional polymerization, a polyester toner extended by a urea bond produced by an underwater granulation method classified as polymerization has been proposed (Patent Document 3). In the step of mixing the release agent dispersion liquid dispersed in a solvent with an oil phase containing another toner composition, when the mixed oil phase is subjected to a large agitation share, the agitation where the mixed oil phase is filled Particles that are composed of only the release agent because the release agent fine particles uniformly dispersed in the oil phase are aggregated between the particles due to local temperature rise in a part of the tank, especially in the vicinity of the stirring means. Has the disadvantage of forming.
Japanese Patent Laid-Open No. 9-43909 Japanese Patent No. 2537503 JP 2003-131430 A

As described above, when granulation is performed using a low melting point release agent by the polymerization method, particles composed of only the release agent containing no pigment are observed. And since the particle | grains comprised only from this mold release agent are very flexible, it will become a factor of filming and sleeve sticking.
Accordingly, an object of the present invention is to provide a fixing device that can prevent filming, sleeve sticking, and the like, is excellent in low-temperature fixability, hot offset resistance, and heat-resistant storage stability, and can achieve an energy saving level that has never been achieved before. It is an object of the present invention to provide a suitable toner production method and a toner produced by the method.

As a result of studying the factors that can form particles composed of only the release agent, the present inventors have found that the temperature of the step of mixing the release agent dispersion in which the release agent is dispersed in a solvent with another toner composition. We found that fluctuations are dominant. That is, when mixing the release agent dispersion liquid once dispersed in the solvent and another toner composition, when a large stirring share is applied to the mixed oil phase, the mixture is filled in the stirring tank filled with the mixed oil phase. It is considered that a local temperature rise occurs in a part of the region, particularly in the vicinity of the stirring means. It was ascertained that the release agent fine particles uniformly dispersed in the oil phase aggregated between the particles due to this temperature rise, forming particles composed only of the release agent.
Therefore, the present inventors solved the problem in granulating the toner containing the release agent as described above by adopting the configuration of the present invention as described below, and forming particles composed only of the release agent. Prevents the formation of uniform toner particles.
The present invention is as follows.

(1) In a toner production method in which a toner containing at least a release agent is granulated in an aqueous system,
A release agent dispersion forming step for dispersing the release agent in a solvent, a mixing step for mixing the release agent dispersion and another toner composition, and a granulation step for granulating the resulting mixture in an aqueous system It has a door,
The release agent has a softening point Tm of 68-80 ° C, and
In the mixing step, the temperature of the entire region in the mixing system is controlled to (Tm- 30) ° C. or lower ,
The percentage of small particles having an equivalent circle diameter of 0.6 to 2 μm is 5% or less.
Method for producing a toner, characterized in that.
( 2 ) The method for producing a toner according to (1), wherein the mixing step is performed in an organic solvent phase, and the toner composition contains at least a binder resin and a pigment.
( 3 ) The toner production method as described in (2) above, wherein the binder resin contains at least a modified polyester (i) having a reactive substituent.
( 4 ) The toner production method as described in ( 3 ) above, wherein the reactive substituent of the modified polyester (i) is an isocyanate group.
(5) A toner produced by the production method according to any one of (1) to ( 4 ) above.
( 6 ) The toner according to ( 5 ), wherein the degree of aggregation is 3 to 20%.
( 7 ) The toner according to ( 5 ) or ( 6 ), wherein the volume average particle diameter (Dv) is 3 to 8 μm.
( 8 ) Any of the above ( 5 ) to ( 7 ), wherein the ratio (Dv / Dn) of the volume average particle diameter (Dv) to the number average particle diameter (Dn) is 1.00 to 1.2 Toner according to.

  According to the present invention, since the temperature of the mixing system at the time of mixing the release agent dispersion and the other toner composition is specified, the occurrence of filming, sleeve sticking, etc. can be prevented, and low temperature fixability Further, it is possible to provide a toner production method suitable for a fixing device that is excellent in hot offset resistance and heat-resistant storage stability and can achieve energy savings that are unprecedented, and a toner produced by the method.

According to the present invention, in a toner manufacturing method in which toner containing at least a release agent is granulated in an aqueous system, a release agent dispersion forming step of dispersing the release agent in a solvent, the release agent dispersion and another toner A mixing step of mixing the composition, and a granulating step of granulating the obtained mixture in an aqueous system, the softening point Tm of the release agent is 68 to 80 ° C., and the mixing step is mixing The temperature of the entire region in the system is controlled to be (Tm- 30) ° C. or lower and above the freezing point of the aqueous phase . It was found that the release agent particles are stably dispersed in the toner particles by being controlled to a temperature of (Tm-30) ° C. or less. This is because the temperature of the entire region in the mixed system is sufficiently lower than the softening point Tm of the release agent, so that the release agent does not melt and the release agent can be stably dispersed. It is thought from.

In the release agent dispersion forming step, the release agent is dispersed using a normal mixing and stirring device. Specifically, the raw material solution in which the release agent is dissolved is stirred in a dissolution stirring tank or the like, and then wet pulverized by an apparatus equipped with granular media such as an attritor, ball mill, sand mill, or vibration mill. As granular media, steels such as stainless steel and carbon steel, alumina, zirconia, silica and the like are preferably used.
In the present invention, the pigment may be added and dispersed simultaneously with the release agent. With the above stirring device, the colorant can be dispersed until the aggregation of the colorant is solved and the average particle diameter of the colorant is about 0.7 μm or less, preferably about 0.4 μm or less. Therefore, it is possible to obtain a clear and excellent color reproduction image with excellent glossiness and transparency when used as a color toner. Further, a part of the binder resin may be introduced and dispersed simultaneously with the release agent.

  Known waxes can be used as the mold release agent of the present invention, and the following materials can be used as the wax component that functions as the mold release agent 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, and chlorinated hydrocarbon, and poly n-stearyl methacrylate and poly n-lauryl methacrylate which are low molecular weight crystalline polymer resins A crystalline polymer having a long alkyl group in the side chain, such as a polyacrylate homopolymer or copolymer (for example, a copolymer of n-stearyl acrylate-ethyl methacrylate, etc.) can also be used.

  The softening point Tm of the release agent of the present invention is preferably 60 to 80 ° C. A wax having a softening point of less than 60 ° C. has an adverse effect on heat-resistant storage stability, and a release agent having a softening point exceeding 80 ° C. tends to cause a cold offset during fixing at a low temperature. Here, the softening point Tm of the release agent in the present invention is determined by the peak top indicating the maximum endotherm of the DSC curve in the differential scanning calorimetry (DSC). The measurement is performed under the following measurement conditions using TA-60WS and DSC-60 manufactured by Shimadzu Corporation.

Measurement conditions Sample container: Aluminum sample pan (with lid)
Sample amount: 5mg
Reference: Aluminum sample pan (alumina 10mg)
Atmosphere: Nitrogen (flow rate 50ml / min)
Temperature conditions Starting temperature: 20 ° C
Temperature increase rate: 10 ° C / min
End temperature: 150 ° C
Holding time: None Temperature drop: 10 ° C / min
End temperature: 20 ° C
Holding time: None Temperature increase rate: 10 ° C / min
End temperature: 150 ° C

  The measurement results were analyzed using the data analysis software (TA-60, version 1.52) manufactured by Shimadzu Corporation. The analysis method specifies a range of ± 5 ° C around the point showing the maximum peak of the DrDSC curve, which is the DSC differential curve of the second temperature rise, and obtains the peak temperature using the peak analysis function of the analysis software. Next, the maximum endothermic temperature of the DSC curve is obtained by using the peak analysis function of the analysis software in the range of the peak temperature + 5 ° C. and −5 ° C. in the DSC curve. The temperature indicated here corresponds to the Tm of the wax.

  Further, the melt viscosity of the release agent is preferably 5 to 1000 cps, more preferably 10 to 100 cps, as a measured value at a temperature 20 ° C. higher than the melting point. A release agent exceeding 1000 cps is poor in improving the hot offset resistance and low temperature fixability. The content of the release agent in the toner is usually 1 to 40% by mass, preferably 3 to 30% by mass.

  In the mixing step of the present invention, the step of mixing the release agent dispersion and the other toner composition is performed using a normal mixing and stirring device. Specifically, the release agent dispersion and other toner composition (preferably containing at least a binder resin and a pigment) are dissolved in a stirring tank or the like with a normal stirring blade such as a U-shaped feather or a V-shaped feather. Then, using an anchor type wing, a helical ribbon type wing, etc., an oil phase (organic solvent phase) that is uniformly stirred and mixed is obtained. In order to further improve the dispersion, the mixed oil phase is dispersed using a dispersion apparatus such as a homomixer (TK Robotics f model, manufactured by Tokushu Kika Kogyo Co., Ltd.) or Ebara Milder (MDN304, manufactured by Taiheiyo Kiko Co., Ltd.). It is preferable to make it. In particular, it is preferable to use an Ebara milder because of its dispersion performance. However, when these dispersing devices are used, when a large stirring share is applied, a local temperature rise occurs in a part of the stirring tank filled with the mixed oil phase, particularly in the vicinity of the stirring means. May cause the fine particles of the release agent uniformly dispersed in the oil phase to agglomerate between the particles and form particles composed only of the release agent. Is preferably maintained at (Tm-30) ° C. or lower with respect to the softening point Tm of the release agent. For this purpose, for example, in the case of an Ebara milder, it is preferable to set the number of passes to 3-12. If the number of passes is less than 3, the dispersion is insufficient, and if the number of passes is more than 12, the temperature rises locally in the vicinity of the stirring means, and the release agent fine particles uniformly dispersed in the oil phase due to this temperature rise May agglomerate between the particles to form particles composed only of the release agent. In addition, it is preferable that the temperature in the whole area | region in the said mixing system is more than the freezing point of the water phase in the granulation process performed after a mixing process.

In the present invention, the mixing step of mixing the release agent dispersion and other toner composition is preferably temperature monitoring with a thermocouple or the like. More preferably, thermography or the like is used so that the entire system to be mixed can be monitored. These means may be used alone, but are preferably used in combination for monitoring. In particular, when dispersing using a dispersing device such as a homomixer or Ebara milder, a local temperature rise occurs particularly in the vicinity of the stirring means, so it is necessary to monitor the temperature of this part.
Specifically, the temperature at the outlet of the mixing section 2 of the Ebara milder is monitored by the sensor as shown in FIG. 1 using a digital thermometer SK-250WP and a sensor SWP-01 manufactured by Sato Keiki Seisakusho. Conventionally, the temperature was monitored at the point shown in FIG. 1A, but in that case, the local temperature rise in the vicinity of the stirring means of the mixing unit 2 could not be monitored, and the release agent fine particles aggregated. There was a case. Therefore, it is preferable to monitor the outlet temperature by positioning the sensor tip at the center of the mixing part outlet pipe indicated by reference numeral 1 in FIG. In FIG. 1, reference numeral 3 denotes a drive motor for a mixing means (not shown) in the mixing section, 4 denotes a raw material tank, and 5 denotes a circulation motor.

  In the present invention, any known binder resin can be used. Specifically, thermoplastic resins, for example, styrenes such as styrene, parachlorostyrene, α-methylstyrene, methyl acrylate, ethyl acrylate, n-propyl acrylate, lauryl acrylate, 2-ethylhexyl acrylate, Esters having unsaturated bonds such as methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, lauryl methacrylate, 2-ethylhexyl methacrylate, nitriles having unsaturated bonds such as acrylonitrile and methacrylonitrile, vinylmethyl Polymer or copolymer using monomers such as ethers, vinyl ethers such as vinyl isobutyl ether, vinyl ketones such as vinyl methyl ketone, vinyl ethyl ketone and vinyl isopropenyl ketone, and olefins such as ethylene, propylene and butadiene Or a mixture thereof, and further, non-vinyl condensation resins such as epoxy resins, polyester resins, polyurethane resins, polyamide resins, cellulose resins, and polyether resins, and the vinyl resins are mixed with these condensation resins. A graft polymer obtained by polymerizing a vinyl monomer in the presence of these polymers can be used. Among these, it is preferable to use a polyester resin in terms of excellent low-temperature fixability and color reproducibility. As the polyester resin, modified polyester (i) or unmodified polyester (ii) can be used. These may be used alone, but it is preferable to use (i) and (ii) in combination because they improve low-temperature fixability and gloss when used in a full-color apparatus. Details of (i) and (ii) will be described below.

In the present invention, the modified polyester means that the polyester resin has a functional group contained in the acid or alcohol monomer unit and a bonding group other than the ester bond, and the polyester resin shares a different resin component. It is in a state of being bonded by bonding, ionic bonding or the like.
For example, the polyester terminal is reacted with something other than an ester bond, specifically, a functional group such as an isocyanate group that reacts with an acid group or a hydroxyl group is introduced at the terminal, and further reacted with an active hydrogen compound, and the terminal is terminated. Those that have been modified or extended are also included.
Furthermore, if it is a compound in which a plurality of active hydrogen groups are present, those in which the polyester ends are bonded together (urea-modified polyester, urethane-modified polyester, etc.) are included. In addition, a reactive group such as a double bond is introduced into the polyester main chain, and radical polymerization is caused therefrom to introduce a carbon-carbon bond graft component into the side chain, or a double bond is bridged. (Styrene-modified, acrylic-modified polyester, etc.).
In addition, a resin component having a different structure is copolymerized in the main chain of the polyester, or reacted with a carboxyl group or a hydroxyl group at the terminal, for example, a silicone having a terminal modified with a carboxyl group, a hydroxyl group, an epoxy group, or a mercapto group Also included are those copolymerized with resins (silicone-modified polyesters, etc.). This will be specifically described below.

  Examples of the polyester (i) modified with a urea bond include a reaction product of a modified polyester (A) having an isocyanate group and amines (B). Examples of the modified polyester (A) having an isocyanate group include a polycondensate of a polyol (1) and a polycarboxylic acid (2) and a polyester having an active hydrogen group further reacted with a polyisocyanate (3). Can be mentioned. Examples of the active hydrogen group possessed by the polyester include a hydroxyl group (alcoholic hydroxyl group and phenolic hydroxyl group), an amino group, a carboxyl group, a mercapto group, and the like. Among these, an alcoholic hydroxyl group is preferable.

  Examples of the polyol (1) include a diol (1-1) and a tri- or higher valent polyol (1-2), and (1-1) alone or a mixture of (1-1) and a small amount of (1-2). Is preferred. Diol (1-1) 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, 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 (ethylene oxide, propylene oxide, butylene oxide, 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. The trihydric or higher polyol (1-2) includes 3 to 8 or higher polyhydric aliphatic alcohols (glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, sorbitol, etc.); trihydric or higher phenols (Trisphenol PA, phenol novolak, cresol novolak, etc.); and alkylene oxide adducts of the above trivalent or higher polyphenols.

  Examples of the polycarboxylic acid (2) include dicarboxylic acid (2-1) and trivalent or higher polycarboxylic acid (2-2). (2-1) alone and (2-1) and a small amount of (2) -2) is preferred. Dicarboxylic acid (2-1) includes alkylene dicarboxylic acid (succinic acid, adipic acid, sebacic acid, etc.); alkenylene dicarboxylic acid (maleic acid, fumaric acid, etc.); aromatic dicarboxylic acid (phthalic acid, isophthalic acid, terephthalic acid) , Naphthalenedicarboxylic acid, etc.). 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 (2-2) include aromatic polycarboxylic acids having 9 to 20 carbon atoms (such as trimellitic acid and pyromellitic acid). In addition, as polycarboxylic acid (2), you may make it react with polyol (1) using the acid anhydride or lower alkyl ester (methyl ester, ethyl ester, isopropyl ester, etc.) of said thing.

  The ratio of the polyol (1) to the polycarboxylic acid (2) 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]. 0.5 / 1 to 1/1, more preferably 1.3 / 1 to 1.02 / 1.

  Examples of the polyisocyanate (3) include aliphatic polyisocyanates (tetramethylene diisocyanate, hexamethylene diisocyanate, 2,6-diisocyanatomethylcaproate, etc.); alicyclic polyisocyanates (isophorone diisocyanate, cyclohexylmethane diisocyanate, etc.); aromatic Diisocyanates (tolylene diisocyanate, diphenylmethane diisocyanate, etc.); araliphatic diisocyanates (α, α, α ′, α′-tetramethylxylylene diisocyanate, etc.); isocyanurates; And a combination of two or more of these.

The ratio of the polyisocyanate (3) is usually 5/1 to 1/1, preferably 4 as the 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, the low-temperature fixability is deteriorated. When the molar ratio of [NCO] is less than 1, the urea content in the modified polyester is lowered and the hot offset resistance is deteriorated. The content of the polyisocyanate (3) component in the modified polyester (A) having an isocyanate group at the terminal is usually 0.5 to 40% by mass, preferably 1 to 30% by mass, and more preferably 2 to 20% by mass. %. If it is less than 0.5% by mass, the hot offset resistance deteriorates, and it is disadvantageous in terms of both heat-resistant storage stability and low-temperature fixability. If it exceeds 40% by mass, the low-temperature fixability deteriorates.
The number of isocyanate groups contained per molecule in the modified polyester (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 a piece. 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 to 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 B1 to B5 amino group blocked (B6) include ketimine compounds and oxazolidine compounds obtained from the B1 to B5 amines and ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.). Among these amines (B), preferred are B1 and a mixture of B1 and a small amount of B2.
Furthermore, if necessary, the molecular weight of the urea-modified polyester can be adjusted using an elongation terminator. Examples of the elongation terminator include monoamines (diethylamine, dibutylamine, butylamine, laurylamine, etc.) and those blocked (ketimine compounds).
The ratio of the amines (B) is the equivalent ratio [NCO] / [NHx] of the isocyanate group [NCO] in the modified polyester (A) having an isocyanate group and the amino group [NHx] in the amine (B). Usually, it is 1/2 to 2/1, preferably 1.5 / 1 to 1 / 1.5, and more preferably 1.2 / 1 to 1 / 1.2. When [NCO] / [NHx] exceeds 2 or less than 1/2, the molecular weight of the urea-modified polyester (i) becomes low, and the hot offset resistance deteriorates.

  In the present invention, the modified polyester (i) 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.

  The modified polyester (i) of the present invention is produced by a one-shot method or a prepolymer method. The weight average molecular weight of the modified polyester (i) 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 the modified polyester is not particularly limited when the unmodified polyester (ii) described below is used, and may be a number average molecular weight that can be easily obtained to obtain the mass average molecular weight. (I) In the case of being independent, the number average molecular weight is usually 20000 or less, preferably 1000 to 10000, and more preferably 2000 to 8000. When it exceeds 20000, the low-temperature fixability and the glossiness when used in a full-color apparatus are deteriorated.

  In the present invention, not only the modified polyester (i) is used alone, but also the polyester (ii) not modified can be contained as a binder resin component together with the (i). By using (ii) in combination, the low-temperature fixability and glossiness when used in a full-color apparatus are improved, which is preferable to single use. Examples of (ii) include the same polycondensates of polyol (1) and polycarboxylic acid (2) as in the polyester component (i) above, and preferred ones are also the same as (i). Further, (ii) is not limited to unmodified polyester, but may be modified with, for example, a urea bond or a urethane bond. It is preferable that (i) and (ii) are at least partially compatible with each other in terms of low-temperature fixability and hot offset resistance. Accordingly, the polyester component (i) and (ii) preferably have similar compositions. When (ii) is contained, the mass ratio of (i) to (ii) is usually 5/95 to 30/70, preferably 5/95 to 25/75, particularly preferably 7/93 to 20/80. It is. If the mass ratio of (i) is less than 5%, the hot offset resistance deteriorates, and it is disadvantageous in terms of both heat-resistant storage stability and low-temperature fixability.

The urea-modified polyester can be produced by the following method. The polyol (1) and the polycarboxylic acid (2) are heated to 150 to 280 ° C. in the presence of a known esterification catalyst such as tetrabutoxytitanate or dibutyltin oxide, and the generated water is distilled off while reducing the pressure as necessary. Thus, a polyester having a hydroxyl group is obtained. Subsequently, this is made to react with polyisocyanate (3) at 40-140 degreeC, and the modified polyester (A) which has an isocyanate group is obtained.
In the case of a urea-modified polyester, the elongation and / or crosslinking reaction time is selected depending on the reactivity of the isocyanate group structure of the modified polyester (A) having a reactive substituent and the amines (B). 10 minutes to 40 hours, preferably 2 to 24 hours. The reaction temperature is generally 0 to 150 ° C, preferably 40 to 98 ° C. Moreover, a well-known catalyst can be used as needed, Specifically, a dibutyltin laurate, a dioctyltin laurate, etc. are mentioned.
Further, (A) is reacted with amines (B) at 0 to 140 ° C. to obtain a polyester modified with a urea bond. When reacting (3) and reacting (A) and (B), a solvent may be used as necessary. When polyester (ii) not modified with urea bond is used in combination, (ii) is produced in the same manner as polyester having a hydroxyl group, and this is dissolved in the solution after completion of the reaction of (i) and mixed. To do.

As the colorant 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 oxidation Iron, ocher, yellow lead, titanium yellow, polyazo yellow, oil yellow, Hansa yellow (GR, A, RN, R), pigment yellow L, benzidine yellow (G, GR), permanent yellow (NCG), Vulcan fast yellow (5G, R), Tartrazine Lake, Quinoline Yellow Lake, Anthrazan Yellow BGL, Isoindolinone Yellow, Bengala, Red Dan, Lead Zhu, Cadmium Red, Cadmium Mercury Red, Antimon Zhu, Permanent Red 4R, Para Red, Faisa Red, Parachloro Tonitroaniline Red, Resol Fast Scarlet G, Brilliant Fast Scarlet, Brilliant Carmine B, Permanent Red (F2R, F4R, FRL, FRLL, F4RH), Fast Scarlet VD, Belkan Fast Rubin B, Brilliant Scarlet G, Resol Rubin GX, Permanent Red F5R, Brilliant Carmine 6B, Pigment Scarlet 3B, Bordeaux 5B, Tolujing Maroon, Permanent Bordeaux F2K, Helio Bordeaux BL, Bordeaux 10B, Bon Maroon Light, Bon Maroon Medium, Eosin Lake, Rhodamine Lake B, Rhodamine Lake Y, Alizarin Lake, thioindigo red B, thioindigo maroon, oil red, quinacridone red, pyrazolo Red, Polyazo Red, Chrome Vermillion, Benzidine Orange, Perinone Orange, Oil Orange, Cobalt Blue, Cerulean Blue, Alkaline Blue Lake, Peacock Blue Lake, Victoria Blue Lake, Metal Free Phthalocyanine Blue, Phthalocyanine Blue, Fast Sky Blue, Indance Ren Blue (RS, BC), Indigo, Ultramarine Blue, Bituminous Blue, Anthraquinone Blue, Fast Violet B, Methyl Violet Lake, Cobalt Purple, Manganese Purple, Dioxane Violet, Anthraquinone Violet, Chrome Green, Zinc Green, Chrome Oxide, Pyridian, Emerald Green , Pigment Green B, Naphthol Green B, Green Gold, Acid Green Lake, Malachite Green Lake Ki, phthalocyanine green, anthraquinone green, titanium oxide, zinc white, litbon and mixtures thereof can be used. The content of the colorant is usually 1 to 15% by mass, preferably 3 to 10% by mass with respect to the toner.
The colorant used in the present invention can also be used as a master batch combined with a resin. In addition to the above modified and unmodified polyester resins, the binder resin to be kneaded with the production of the masterbatch or the masterbatch is a polymer of styrene such as polystyrene, poly-p-chlorostyrene, polyvinyltoluene, and the like, or a substituted product 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-chloro Methyl methacrylate copolymer, styrene Acrylonitrile copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile-indene copolymer, styrene-maleic acid copolymer, styrene-maleic acid ester Styrene copolymers such as copolymers; polymethyl methacrylate, polybutyl methacrylate, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, polyester, epoxy resin, epoxy polyol resin, polyurethane, polyamide, polyvinyl butyral, polyacrylic acid Resins, rosins, modified rosins, terpene resins, aliphatic or alicyclic hydrocarbon resins, aromatic petroleum resins, chlorinated paraffins, paraffin waxes and the like can be used, and these can be used alone or in combination.

  This master batch can be obtained by mixing and kneading a master batch resin and a colorant under high shearing force. At this time, an organic solvent can be used in order to enhance the interaction between the colorant and the resin. In addition, a so-called flushing method, which is a wet cake of a colorant, is a method of mixing and kneading an aqueous paste containing water of a colorant together with a resin and an organic solvent, transferring the colorant to the resin side, and removing moisture and organic solvent components. 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 having a three-roll mill or the like is preferably used.

  The toner of the present invention may contain a charge control agent as necessary. As the charge control agent, all known ones can be used. For example, nigrosine dyes, triphenylmethane dyes, chromium-containing metal complex dyes, molybdate chelate pigments, rhodamine dyes, alkoxy amines, quaternary ammonium salts ( Fluorine-modified quaternary ammonium salts), alkylamides, phosphorus simple substances or compounds, tungsten simple substances or compounds, fluorine activators, salicylic acid metal salts and metal salts of salicylic acid derivatives. Specifically, Bontron 03 of nigrosine dye, Bontron P-51 of quaternary ammonium salt, Bontron S-34 of metal-containing azo dye, E-82 of oxynaphthoic acid metal complex, E of salicylic acid metal complex -84, phenolic condensate E-89 (above, Orient Chemical Industries), quaternary ammonium salt molybdenum complex TP-302, TP-415 (above, Hodogaya Chemical Co., Ltd.), quaternary Copy charge PSY VP2038 of ammonium salt, copy blue PR of triphenylmethane derivative, copy charge of quaternary ammonium salt NEG VP2036, copy charge NX VP434 (above, manufactured by Hoechst), LRA-901, LR- which is a boron complex 147 (manufactured by Nippon Carlit), copper phthalocyanine, perylene, quinaclide , Azo pigments, sulfonate group, carboxyl group, and polymer compounds having a functional group such as a quaternary ammonium salt.

  The amount of charge control agent used in the present invention 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. However, it is preferably used in the range of 0.1 to 10 parts by mass with respect to 100 parts by mass of the binder resin. Preferably, the range of 0.2-5 mass parts is good. When the amount exceeds 10 parts by mass, the chargeability of the toner is too high, the effect of the main charge control agent is reduced, the electrostatic attraction force with the developing roller is increased, the flowability of the developer is reduced, and the image density Cause a decline. These charge control agents can be melt-kneaded together with the master batch and the resin, and may be added when dissolved and dispersed in the organic solvent.

As the external additive used for assisting the fluidity, developability and chargeability of the toner obtained in the present invention, inorganic fine particles can be preferably used. The primary particle size of the inorganic fine particles is preferably 5 mμ to 2 μm, 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 use ratio of the inorganic fine particles is preferably 0.01 to 5% by mass of the toner, and particularly preferably 0.01 to 2.0% by mass. Specific examples of the inorganic fine particles include, for example, silica, alumina, titanium oxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate, zinc oxide, tin oxide, silica sand, clay, mica, wollastonite, Examples thereof include diatomaceous earth, chromium oxide, cerium oxide, bengara, antimony trioxide, magnesium oxide, zirconium oxide, barium sulfate, barium carbonate, calcium carbonate, silicon carbide, and silicon nitride.
In addition, polymer fine particles, for example, polystyrene obtained by soap-free emulsion polymerization, suspension polymerization, dispersion polymerization, methacrylic acid ester or acrylate copolymer, polycondensation system such as silicone, benzoguanamine, nylon, thermosetting Polymer particles made of a functional resin.
Such a fluidizing agent increases the hydrophobicity by performing a surface treatment, and can prevent the deterioration of the flow characteristics and charging characteristics even under high humidity. For example, silane coupling agents, silylating agents, silane coupling agents having an alkyl fluoride group, organic titanate coupling agents, aluminum coupling agents, silicone oils, modified silicone oils and the like are preferred surface treatment agents. It is done.

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

  Solvents usable in the present invention include aromatic solvents (toluene, xylene, etc.); ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.); esters (ethyl acetate, etc.); amides (dimethylformamide, dimethylacetamide, etc.) ) And ethers (tetrahydrofuran, etc.) and the like are inert to the isocyanate (3).

  In the granulation step, the aqueous medium to be used may be water alone, or a solvent miscible with water may be used in combination. Examples of the solvent miscible with water include alcohol (methanol, isopropanol, ethylene glycol, etc.), dimethylformamide, tetrahydrofuran, cellosolves (methyl cellosolve, etc.), lower ketones (acetone, methyl ethyl ketone, etc.) and the like.

The toner particles may be formed by reacting a dispersion composed of a modified polyester (A) having a substituent capable of reacting in an aqueous medium with (B), or using a modified polyester (i) produced in advance. Good.
A method for dispersing the toner raw material in the aqueous medium is not particularly limited, and known equipment such as a low-speed shearing type, a high-speed shearing type, a friction type, a high-pressure jet type, and an ultrasonic wave can be applied. In order to make the particle diameter of the dispersion 2 to 20 μm, a high-speed shearing method is preferable. When a high-speed shearing disperser is used, the rotation 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 at the time of dispersion is preferably not less than the freezing point of the aqueous phase and not more than (Tm-30) ° C. with respect to the softening point Tm of the release agent, but the higher temperature is capable of reacting with the modified polyester (i). The dispersion made of the modified polyester (A) having a substituent is preferable in terms of low viscosity and easy dispersion.

  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 the modified polyester (i) and the modified polyester (A) having a reactive substituent. is there. If the amount is less than 50 parts by mass, the dispersion state of the toner composition is poor, and toner particles having a predetermined particle diameter cannot be obtained. If it exceeds 20000 parts by mass, it is not economical. Moreover, a dispersing agent can also be used as needed. The use of a dispersant is preferable in that the particle size distribution becomes sharp and the dispersion is stable.

  Dispersants used for emulsifying and dispersing the oil phase in which the toner raw material is dispersed in a liquid containing water include anionic surfactants such as alkylbenzene sulfonates, α-olefin sulfonates, and phosphate esters, Amine salt types such as alkylamine salts, amino alcohol fatty acid derivatives, polyamine fatty acid derivatives, imidazoline, alkyltrimethylammonium salts, dialkyldimethylammonium salts, alkyldimethylbenzylammonium salts, pyridinium salts, alkylisoquinolinium salts, benzethonium chloride Nonionic surfactants such as quaternary ammonium salt type cationic surfactants, fatty acid amide derivatives, polyhydric alcohol derivatives such as alanine, dodecyldi (aminoethyl) glycine, di (octylaminoethyl) glycine and N -Alkyl N, amphoteric surface active agents such as N- dimethylammonium betaine.

In addition, by using a surfactant having a fluoroalkyl group, the effect can be increased 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 to C11). Oxy] -1-alkyl (C3-C4) sodium sulfonate, 3- [omega-fluoroalkanoyl (C6-C8) -N-ethylamino] -1-propanesulfonic acid sodium, fluoroalkyl (C11-C20) carboxylic acid And metal salts, perfluoroalkyl carboxylic acids (C7 to C13) and metal salts thereof, perfluoroalkyl (C4 to C12) sulfonic acids and metal salts thereof, perfluorooctane sulfonic acid diethanolamide, N-propyl-N- (2 Hydroxyethyl) -Fluorooctanesulfonamide, perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salt, perfluoroalkyl (C6-C10) -N-ethylsulfonylglycine salt, monoperfluoroalkyl (C6-C16) ethyl phosphate, etc. Is mentioned.
Product names include Surflon S-111, S-112, S-113 (Asahi Glass Co., Ltd.), Florard FC-93, FC-95, FC-98, FC-129 (Sumitomo 3M Co., Ltd.), Unidyne DS-101. DS-102 (Daikin Kogyo Co., Ltd.), MegaFuck F-110, F-120, F-113, F-191, F-812, F-833 (Dainippon Ink Co., Ltd.), Xtop EF-102 , 103, 104, 105, 112, 123A, 123B, 306A, 501, 201, 204 (manufactured by Tochem Products), and Fgentent F-100, F150 (manufactured by Neos).
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).

Further, as the inorganic compound dispersant that is hardly soluble in water, tricalcium phosphate, calcium carbonate, titanium oxide, colloidal silica, hydroxyapatite, and the like can be used.
Further, the dispersed droplets may be stabilized by a polymer protective colloid. For example, acrylic acid, methacrylic acid, α-cyanoacrylic acid, α-cyanomethacrylic acid, itaconic acid, crotonic acid, fumaric acid, maleic acid, maleic anhydride, and other acids, or (meth) acrylic simple substances containing hydroxyl groups Mer, for example, β-hydroxyethyl acrylate, β-hydroxyethyl methacrylate, β-hydroxypropyl acrylate, β-hydroxypropyl methacrylate, γ-hydroxypropyl acrylate, γ-hydroxypropyl methacrylate, acrylic acid 3-chloro-2-hydroxypropyl, 3-chloro-2-hydroxypropyl methacrylate, diethylene glycol monoacrylate, diethylene glycol monomethacrylate, glycerol monoacrylate, glycerol monomethacrylate, N- Methylol acrylamide, N-methylol methacrylamide, etc., vinyl alcohol or ethers with vinyl alcohol, such as vinyl methyl ether, vinyl ethyl ether, vinyl propyl ether, etc., or esters of compounds containing vinyl alcohol and carboxyl groups, such as , Pinyl acetate, vinyl propionate, vinyl butyrate, etc., acrylamide, methacrylamide, diacetone acrylamide or their methylol compounds, acid chlorides such as acrylic acid chloride, methacrylic acid chloride, pinyl 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, polyoxyethylene alkyl Such as amine, polyoxypropylene alkylamine, polyoxyethylene alkylamide, polyoxypropylene alkylamide, polyoxyethylene nonyl phenyl ether, polyoxyethylene lauryl phenyl ether, polyoxyethylene stearyl phenyl ester, polyoxyethylene nonyl phenyl ester Celluloses such as polyoxyethylene, methylcellulose, hydroxyethylcellulose, hydroxypropylcellulose and the like can be used.

  Furthermore, in order to lower the viscosity of the toner raw material, a solvent in which the modified polyester (i) or (A) is soluble can be used. The use of a solvent is preferable in that the particle size distribution becomes sharp. This solvent is preferably volatile with a boiling point of less than 100 ° C. from the viewpoint of easy removal. Examples of such solvents include toluene, xylene, benzene, carbon tetrachloride, methylene chloride, 1,2-dichloroethane, 1,1,2-trichloroethane, trichloroethylene, chloroform, monochlorobenzene, dichloroethylidene, methyl acetate, acetic acid. Ethyl, methyl ethyl ketone, methyl isobutyl ketone and the like can be used alone or in combination of two or more. In particular, aromatic solvents such as toluene and xylene and halogenated hydrocarbons such as methylene chloride, 1,2-dichloroethane, chloroform and carbon tetrachloride are preferred. The usage-amount of the solvent with respect to 100 mass parts of modified polyester (A) which has a reactive substituent is 0-300 mass parts normally, Preferably it is 0-100 mass parts, More preferably, it is 25-70 mass parts.

In order to remove the organic solvent from the obtained emulsified dispersion, a method in which the temperature of the entire system is gradually raised to completely evaporate and remove the organic solvent in the droplets can be employed. It is also possible to spray the emulsified dispersion in a dry atmosphere to completely remove the water-insoluble organic solvent in the droplets to form toner fine particles, and to evaporate and remove the aqueous dispersant together. As a dry atmosphere in which the emulsified dispersion is sprayed, a gas obtained by heating air, nitrogen, carbon dioxide gas, combustion gas, or the like, in particular, various air currents heated to a temperature equal to or higher than the boiling point of the highest boiling solvent used is generally used. A spray dryer, belt dryer, rotary kiln, etc. can provide the desired quality in a short time.
In addition, when an acid such as calcium phosphate salt or an alkali-soluble material is used as the dispersion stabilizer, the calcium phosphate salt is removed from the fine particles by a method such as dissolving the calcium phosphate salt with an acid such as hydrochloric acid and then washing with water. To do. In addition, it can be removed by an operation such as enzymatic degradation. When a dispersant is used, the dispersant can remain on the surface of the toner particles. However, it is preferable from the charged surface of the toner that the dispersant is washed and removed after the elongation and / or crosslinking reaction.

  When the particle size distribution at the time of emulsification dispersion is wide and washing and drying processes are performed while maintaining the particle size distribution, the particle size distribution can be adjusted by classifying into a desired particle size distribution. In the classification operation, the fine particle portion can be removed in the liquid by a cyclone, a decanter, centrifugation, or the like. Although classification operation may be performed after obtaining as powder after drying, it is preferable in terms of efficiency to be performed in a liquid. The obtained unnecessary fine particles or coarse particles can be returned to the kneading step and used for forming particles. At that time, fine particles or coarse particles may be wet. The dispersant used is preferably removed from the obtained dispersion as much as possible, but it is preferable to carry out it simultaneously with the above classification operation.

The obtained dried toner powder is mixed with different particles such as charge control fine particles, fluidizing agent fine particles, and colorant fine particles, or fixed on the surface by applying mechanical impact force to the mixed powder. By fusing, it is possible to prevent detachment of foreign particles from the surface of the resulting composite particles.
Specific means include a method of applying an impact force to the mixture by blades rotating at high speed, a method of injecting and accelerating the mixture into a high-speed air stream, and causing particles or composite particles to collide with an appropriate collision plate, etc. is there. As equipment, Ong mill (manufactured by Hosokawa Micron Co., Ltd.), I-type mill (manufactured by Nippon Pneumatic Co., Ltd.) is modified to reduce the grinding air pressure, hybridization system (manufactured by Nara Machinery Co., Ltd.), kryptron system (Manufactured by Kawasaki Heavy Industries, Ltd.), automatic mortar and the like.
According to such a production method, it is possible to obtain a toner that is excellent in powder flowability and transferability, and provides a high-quality image with a small particle diameter. Furthermore, it is excellent in low-temperature fixability and hot offset resistance and does not cause filming spent. Thus, toners that satisfy various required characteristics, including pulverized toners, have not been obtained conventionally.

The peak molecular weight of the toner is usually 1000 to 30000, preferably 1500 to 10000, and more preferably 2000 to 8000. If it is less than 1000, heat-resistant storage stability will deteriorate, and if it exceeds 30000, low-temperature fixability will deteriorate.
Here, the peak molecular weight of the toner in the present invention is specifically determined by the following procedure.

(Measurement of peak molecular weight of toner)
Gel permeation chromatography (GPC) measuring device: GPC-8220GPC (manufactured by Tosoh Corporation)
Column: TSKgel SuperHZM-H 15cm triple (made by Tosoh Corporation)
Temperature: 40 ° C
Solvent: THF
Flow rate: 0.35 ml / min
Sample: 0.4 ml of 0.15% sample was injected Sample pretreatment: The toner was dissolved in tetrahydrofuran THF (made by Wako Pure Chemical Industries, Ltd.) at 0.15% by mass and filtered through a 0.2 μm filter. The filtrate is used as a sample. 100 μl of the THF sample solution is injected and measured. In measuring the molecular weight of a sample, the molecular weight distribution of the sample is calculated from the relationship between the logarithmic value of a calibration curve prepared from several types of monodisperse polystyrene standard samples and the number of counts. As standard polystyrene samples for creating a calibration curve, Showdex STANDARD Std.No S-7300, S-210, S-390, S-875, S-1980, S-10.9, S-629, S-3.0, S-0.580, and toluene were used. An RI (refractive index) detector was used as the detector.

  The hydroxyl value of the toner is preferably 5 or more, more preferably 10 to 120, and particularly preferably 20 to 80. If it is less than 5, it is disadvantageous in terms of both heat-resistant storage stability and low-temperature fixability. The acid value of the toner is usually 1 to 40, preferably 5 to 30, and more preferably 15 to 28. By giving an acid value, it tends to be negatively charged, and the affinity with paper at the time of fixing is increased, and the fixing power is increased.

Here, the acid value (AV) and the hydroxyl value (OHV) in the present invention are specifically determined by the following procedure.
Measuring device: Potentiometric automatic titrator DL-53 Titrator (Metler Toledo)
Working electrode: 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.

(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 toner (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 obtain 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)
(Measurement method of hydroxyl value)
Weigh accurately 0.5 g of sample into a 100 ml volumetric flask and add 5 ml of acetylating reagent correctly. Then, it is immersed in a bath at 100 ° C. ± 5 ° C. and heated. After 1-2 hours, the flask is removed from the bath, allowed to cool, water is added and shaken to decompose acetic anhydride. Further, in order to complete the decomposition, the flask is again heated in a bath for 10 minutes or more and allowed to cool, and then the wall of the flask is thoroughly washed with an organic solvent. This solution is subjected to potentiometric titration with an N / 2 potassium hydroxide ethyl alcohol solution using the electrode to determine the OH value (according to JISK0070-1966).

In the present invention, the glass transition point (Tg) of the toner is usually 40 to 70 ° C., preferably 45 to 60 ° C. If it is less than 40 ° C., the heat-resistant storage stability of the toner deteriorates, and if it exceeds 70 ° C., the low-temperature fixability becomes insufficient. Due to the coexistence of the modified polyester resin, the toner of the present invention tends to have good heat-resistant storage stability even when the glass transition point is low, as compared with a known polyester toner.
Here, the glass transition point (Tg) in the present invention is specifically determined by the following procedure. Shimadzu TA-60WS and DSC-60 were used as measurement devices, and the measurement was performed under the following measurement conditions.

Measurement conditions Sample container: Aluminum sample pan (with lid)
Sample amount: 5mg
Reference: Aluminum sample pan (alumina 10mg)
Atmosphere: Nitrogen (flow rate 50ml / min)
Temperature conditions Starting temperature: 20 ° C
Temperature increase rate: 10 ° C / min
End temperature: 150 ° C
Holding time: None Temperature drop: 10 ° C / min
End temperature: 20 ° C
Holding time: None Temperature increase rate: 10 ° C / min
End temperature: 150 ° C

  The measurement results were analyzed using the data analysis software (TA-60, version 1.52) manufactured by Shimadzu Corporation. The analysis method specifies a range of ± 5 ° C centering on the point showing the maximum peak on the lowest temperature side of the DrDSC curve which is the DSC differential curve of the second temperature rise, and the peak temperature is determined using the peak analysis function of the analysis software. Ask. Next, the maximum endothermic temperature of the DSC curve is obtained by using the peak analysis function of the analysis software in the range of the peak temperature + 5 ° C. and −5 ° C. in the DSC curve. The temperature shown here corresponds to the Tg of the toner.

In the toner of the present invention, it is preferable that the cohesive force is small. When the cohesive force of the toner is small, the charge of each toner becomes uniform and toner scattering can be reduced.
Here, the cohesion force of the toner can be expressed as an aggregation degree (%). It can be said that the larger the cohesion value, the stronger the cohesion of the toner.
The aggregation degree of the toner is preferably 3 to 20%. If the degree of aggregation is less than 3%, the fluidity of the toner is too good and toner scattering is likely to occur during transfer. If it exceeds 20%, the toner scattering during development and transfer deteriorates. There are things to do.
Here, the degree of aggregation was measured using a powder tester (PT-N type, manufactured by Hosokawa Micron Corporation). That is, the amount of toner remaining on each sieve when 2.0 g of toner was passed through sieves with a mesh size of 150 μm, 75 μm, and 45 μm (plain woven wire mesh, standard JIS Z 8801-1) was measured and shown below. Calculated using the formula.
Aggregation degree (%) = (A + 0.6 × B + 0.2 × C) /2.0×100
A: Remaining toner amount (g) on a sieve having an opening of 150 μm, B: Remaining toner amount (g) on a sieve having an opening of 75 μm, C: Remaining toner amount (g) on a sieve having an opening of 45 μm

The volume average particle size of the toner of the present invention is preferably 3 to 8 μm. If it is larger than 8 μm, it is difficult to obtain a high-quality image, and if it is smaller than 3 μm, transferability and cleaning properties are deteriorated, and filming and spent on the carrier are likely to occur.
In the present invention, the ratio Dv / Dn of the volume average particle diameter Dv to the number average particle diameter Dn of the toner is preferably 1.00 to 1.20. With such a toner, it is excellent in all of heat-resistant storage stability, low-temperature fixability, and hot offset resistance, particularly excellent in image glossiness when used in a full-color copying machine, etc. Even if the toner balance is extended over a wide range, fluctuations in the toner particle size in the developer are reduced, and good and stable developability can be obtained even with long-term stirring in the developing device. Even when used as a one-component developer, even if the balance of the toner is performed, the fluctuation of the toner particle size is reduced, and the toner is filmed on the developing roller and the toner is thinned. The toner was not fused to a member such as a blade, and good and stable developability and images were obtained even when the developing device was used (stirred) for a long time.

  The volume average particle diameter (Dv) and the number average particle diameter (Dn) of the toner are measured with a particle size measuring device (“Multisizer III”, manufactured by Beckman Coulter, Inc.) at an aperture diameter of 100 μm, and analyzed with software (Beckman Coulter Multisizer). 3 Version 3.51). Specifically, 0.5 ml of 10 wt% surfactant (alkylbenzene sulfonate Neogen SC-A; Daiichi Kogyo Seiyaku) was added to a glass 100 ml beaker, 0.5 g of each toner was added, and the mixture was stirred with a micropartel. Subsequently, 80 ml of ion-exchanged water was added. The obtained dispersion was subjected to a dispersion treatment for 10 minutes with an ultrasonic disperser (W-113MK-II, manufactured by Honda Electronics Co., Ltd.). The dispersion was measured using the Multisizer III and Isoton III (manufactured by Beckman Coulter) as the measurement solution. In the measurement, the toner sample dispersion was dropped so that the concentration indicated by the apparatus was 8 ± 2%. In this measurement method, it is important that the concentration is 8 ± 2% from the viewpoint of the reproducibility of the particle size. Within this concentration range, no error occurs in the particle size.

In the present invention, the ratio of small particles having an equivalent circle diameter of 0.6 to 2 μm is preferably 5% or less. The small particle ratio is measured as follows. Measurement is performed using a flow particle image analyzer (“FPIA-2100”; manufactured by Sysmex Corporation), and analysis is performed using analysis software (FPIA-2100 Data Processing Program for FPIA version 00-10). Specifically, 0.1 to 0.5 ml of 10% by weight surfactant (alkylbenzene sulfonate Neogen SC-A; Daiichi Kogyo Seiyaku) is added to a glass 100 ml beaker, and each toner 0.1 to Add 0.5 g and stir with microspatel, then add 80 ml of ion-exchanged water. The obtained dispersion is subjected to a dispersion treatment for 3 minutes with an ultrasonic disperser (manufactured by Honda Electronics Co., Ltd.). The shape and distribution of the toner are measured using the FPIA-2100 until the concentration of 5000 to 15000 / μl is 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.
The ratio of small particles having an equivalent circle diameter of 0.6 to 2 μm is preferably 5% or less when the analysis standard by the flow type particle image analyzer of the toner of the present invention based on the measurement method is based on the number. When the ratio of small particles having an equivalent circle diameter of 0.6 to 2 μm on the basis of the number analysis exceeds 5%, transferability and cleaning properties are deteriorated, and filming and spent on the carrier are likely to occur.

  When the toner of the present invention is used for a two-component developer, it may be used by mixing it with a magnetic carrier. The carrier to toner content ratio in the developer is 1 to 10 toners per 100 parts by mass of the carrier. Part by mass is preferred. 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. In addition, polyvinyl and polyvinylidene resins, for example, acrylic resins, polymethyl methacrylate resins, polyacrylonitrile resins, polyvinyl acetate resins, polyvinyl alcohol resins, polyvinyl butyral resins, polystyrene resins and polystyrene resins such as styrene acrylic copolymer resins, Halogenated olefin resins such as polyvinyl chloride, polyester resins such as polyethylene terephthalate resin and polybutylene terephthalate resin, polycarbonate resins, polyethylene resins, polyvinyl fluoride resins, polyvinylidene fluoride resins, polytrifluoroethylene resins, poly Hexafluoropropylene resin, copolymer of vinylidene fluoride and acrylic monomer, copolymer of vinylidene fluoride and vinyl fluoride, tetrafluoroethylene and vinylidene fluoride Fluoro terpolymers and silicone resins such terpolymers, etc. of the non-fluoric monomers including can be used. 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 size of 1 μm or less. When the average particle diameter is larger than 1 μm, it becomes difficult to control the electric resistance.

  The toner of the present invention can also be used as a one-component magnetic toner or non-magnetic toner that does not use a carrier.

  Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited thereto.

Example 1
--Preparation of fine particle dispersion 1--
In a reaction vessel in which a stir bar and a thermometer are set, 683 parts by mass of water, 11 parts by mass of sodium salt of ethylene oxide methacrylate adduct sulfate (Eleminol RS-30, manufactured by Sanyo Chemical Industries), 83 parts by mass of styrene, methacrylic acid When 83 parts by mass, 110 parts by mass of butyl acrylate, and 1 part by mass of ammonium persulfate were charged and stirred for 15 minutes at 400 rpm, 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 by mass of a 1% aqueous ammonium persulfate solution was added, and the mixture was aged at 75 ° C. for 5 hours to form a vinyl resin (a copolymer of styrene-methacrylic acid-butyl acrylate-methacrylic acid ethylene oxide adduct sulfate sodium salt). An aqueous dispersion [fine particle dispersion 1] was obtained. The volume average particle diameter of [fine particle dispersion 1] measured by LA-920 was 105 nm. A portion of [Fine Particle Dispersion 1] was dried to isolate the resin component. The Tg of the resin was 59 ° C., and the mass average molecular weight was 150,000.

--Synthesis of polyester resin (1)-
In a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen introduction tube, 229 parts by mass of bisphenol A ethylene oxide 2 mol adduct, 529 parts by mass of bisphenol A propylene oxide 3 mol adduct, 208 parts by mass of terephthalic acid, 46 adipic acid 46 2 parts by weight of dibutyltin oxide and 2 parts by weight of dibutyltin oxide were reacted at normal pressure and 230 ° C. for 8 hours, and further reacted at 10 to 15 mmHg for 5 hours, and then 30 parts by weight of trimellitic anhydride was added to the reaction vessel. The polyester resin (1) was obtained by reacting at 180 ° C. and normal pressure for 2 hours. The polyester resin (1) had a mass average molecular weight (Mw) of 6,700, a glass transition temperature (Tg) of 43 ° C., and an acid value of 20 mgKOH / g.

-Preparation of aqueous phase-
990 parts by weight of water, 183 parts by weight of the fine particle dispersion, 37 parts by weight of an aqueous solution of 48.5% by weight of sodium dodecyl diphenyl ether disulfonate (“Eleminol MON-7”; manufactured by Sanyo Chemical Industries), and 90 parts by weight of ethyl acetate The mixture was stirred to obtain a milky white liquid (aqueous phase).

--Synthesis of low molecular weight polyester--
In a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen introduction tube, 682 parts by mass of bisphenol A ethylene oxide 2 mol adduct, 81 parts by mass of bisphenol A propylene oxide 2 mol adduct, 283 parts by mass of terephthalic acid, trimellitic anhydride A low molecular weight polyester was synthesized by charging 22 parts by mass of an acid and 2 parts by mass of dibutyltin oxide and reacting at 230 ° C. for 5 hours under normal pressure.
The obtained low molecular weight polyester has a number average molecular weight (Mn) of 2,100, a mass average molecular weight (Mw) of 9,500, a glass transition temperature (Tg) of 55 ° C., and an acid value of 0.5 mgKOH / g. The hydroxyl value was 51.

--Synthesis of modified polyester having a reactive substituent--
In a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen introduction tube, 410 parts by mass of the low molecular weight polyester, 89 parts by mass of isophorone diisocyanate, and 500 parts by mass of ethyl acetate were charged and reacted at 100 ° C. for 5 hours. A modified polyester having a reactive substituent (polymer capable of reacting with the active hydrogen group-containing compound) was synthesized.
The free isocyanate content of the obtained modified polyester having a reactive substituent was 1.53% by mass.

-Preparation of master batch (MB)-
1200 parts by mass of water, 540 parts by mass of carbon black (“Printex 35”; manufactured by Dexa, DBP oil absorption = 42 ml / 100 mg, pH = 9.5) as a colorant, and 1200 parts by mass of the polyester resin (1) It mixed with the mixer (made by Mitsui Mining). The mixture was kneaded with a two-roller at 150 ° C. for 30 minutes, rolled and cooled, and pulverized with a pulverizer (manufactured by Hosokawa Micron) to prepare a master batch.

-Preparation of organic solvent phase-
In a reaction vessel in which a stir bar and a thermometer were set, 378 parts by mass of the polyester resin (1), 110 parts by mass of paraffin wax (HNP-11 manufactured by Nippon Seiki), and 947 parts by mass of ethyl acetate were charged. The temperature was raised to 80 ° C. and kept at 80 ° C. for 30 hours, and then cooled to 30 ° C. over 1 hour to obtain a raw material solution.
1324 parts by mass of the obtained raw material solution was transferred to a reaction vessel, and using a bead mill (“Ultra Visco Mill”; manufactured by Imex Co., Ltd.), the liquid feeding speed was 1 kg / hr, the disk peripheral speed was 6 m / sec, and 0.5 mm zirconia. The paraffin wax was dispersed by dispersing for 9 hours under the condition of 80% by volume of beads.
Next, 1324 parts by mass of a 65% by mass ethyl acetate solution of the low molecular weight polyester was added to the dispersion, and 500 parts by mass of the master batch and 500 parts by mass of ethyl acetate were charged and mixed for 1 hour. Next, the mixed liquid was kept at 25 ° C., and passed through an ebara milder (a combination of G, M, and S from the inlet side) at a flow rate of 1 kg / min for 4 passes to prepare an organic solvent phase (pigment / wax dispersion).
The solid content concentration of the obtained organic solvent phase (130 ° C., 30 minutes) was 50% by mass.

--Emulsification / Dispersion--
Into a reaction vessel, 749 parts by mass of the organic solvent phase, 115 parts by mass of the modified polyester having a reactive substituent, and 2.9 parts by mass of isophoronediamine (manufactured by Wako Pure Chemical Industries) compound were charged. TK homomixer MKII) for 1 minute at a rotation speed of 5,000 rpm, 1200 parts by mass of the aqueous phase was added to the reaction vessel, and 25 minutes at a rotation speed of 9,000 rpm with the homomixer. Mix at 3 ° C. for 3 minutes. Thereafter, the mixture was stirred with a stirrer for 20 minutes to prepare an emulsified slurry.
Next, the emulsified slurry was charged into a reaction vessel equipped with a stirrer and a thermometer, and the solvent was removed at 25 ° C. After removing the organic solvent, aging was performed at 45 ° C. for 15 hours to obtain a dispersed slurry.
The obtained dispersion slurry had a volume average particle size of 4.53 μm and a number average particle size of 4.19 μm as measured by Multisizer III (manufactured by Beckman Coulter, Inc.).

-Cleaning process-
After 100 parts by mass of the dispersion slurry was filtered under reduced pressure, 100 parts by mass of ion-exchanged water was added to the filter cake, mixed with a homomixer (rotation speed: 8,000 rpm for 10 minutes), and then filtered. 100 parts by mass of ion-exchanged water was added to the obtained filter cake, mixed with a homomixer (rotation speed: 8,000 rpm for 10 minutes), and then filtered under reduced pressure. 100 mass parts of 10 mass% sodium hydroxide aqueous solution was added to the filter cake obtained here, it mixed with the homomixer (10 minutes at a rotational speed of 8,000 rpm), and then filtered. 100 mass parts of 10 mass% hydrochloric acid was added to the filter cake obtained here, and after mixing with a homomixer (rotation speed 8,000 rpm for 10 minutes), it filtered. 300 mass parts of ion-exchanged water was added to the filter cake obtained here, and after mixing with a homomixer (rotating speed of 8,000 rpm for 10 minutes), filtration was performed twice to obtain a final filter cake. The final filter cake obtained here was dried at 45 ° C. for 48 hours with a circulating drier and sieved with a mesh having a mesh size of 75 μm, whereby toner base particles of Example 1 were obtained.

--External additive treatment--
The toner base particles obtained in Examples 1 to produce a toner 1 of the actual Example 1 was mixed with an external additive. The toner of Example 1 was evaluated. Table 2 shows toner production conditions, and Table 3 shows toner evaluation results.

(Example 2)
Toner 2 was obtained in the same manner as in Example 1 except that the mixing temperature of the liquid mixture during preparation of the organic solvent phase was changed to 10 ° C.

(Example 3)
Toner 3 was obtained in the same manner as in Example 1 except that the paraffin wax in Example 1 (HNP-11, manufactured by Nippon Seiki) was changed to HNP-9, manufactured by Nihon Seiki.

( Reference Example 4)
Toner 4 was obtained in the same manner as in Example 1 except that the paraffin wax of Example 1 (HNP-11 manufactured by Nippon Seiki) was changed to SP-0145 manufactured by Nippon Seiki.

(Example 5)
Toner 5 was obtained in the same manner as in Example 3 except that the mixing temperature of the mixed solution at the time of preparing the organic solvent phase was changed to 45 ° C.

(Comparative Example 1)
Toner 6 was obtained in the same manner as in Example 3 except that the mixing temperature of the mixed solution during preparation of the organic solvent phase was changed to 55 ° C.

(Comparative Example 2)
Toner 7 was obtained in the same manner as in Example 1 except that the paraffin wax of Example 1 (HNP-11 manufactured by Nippon Seiki) was changed to paraffin wax (paraffin wax 115 manufactured by Nippon Seiki).

(1) Fixability Ricoh Copier with Teflon (registered trademark) roller as the fixing roller MF2200 Using a machine with a modified fixing part, set Ricoh type 6200 paper on this to perform a copy test It was. The results at this time are shown in Table 3.
The cold offset temperature (fixing lower limit temperature) and the hot offset temperature (hot offset temperature resistance) were determined by changing the fixing temperature. The conventional fixing minimum temperature of the low-temperature fixing toner is about 140 to 150 ° C. The evaluation conditions for low-temperature fixing are a paper feed linear velocity of 120 to 150 mm / sec, a surface pressure of 1.2 kgf / cm ² , a nip width of 3 mm, and a hot offset evaluation condition of a paper feed linear velocity of 50 mm / sec. The surface pressure was set to 2.0 kgf / cm ² and the nip width was 4.5 mm. The criteria for each characteristic evaluation are as follows.

Low-temperature fixability (5-level evaluation)
5 ... Less than 120 ° C 4 ... More than 120 ° C and 140 ° C or less 3 ... More than 140 ° C and less than 150 ° C 2 ... More than 150 ° C and less than 160 ° C 1 ... More than 160 ° C Hot offset property (5 steps) Evaluation)
5 ... 201 ° C or higher 4 ... 200-191 ° C
3 ... 190-181 ° C
2 ... 180-171 ° C
1 ... 170 ℃ or less

(2) Filming Set the developer and toner in a filming evaluation machine modified from the development unit of Ricoh Co., Ltd. imagioMF-4550, and print solid black in a room temperature environment of 23 ° C and 55% humidity. 2 A4 horizontal charts (image pattern A) in which the width is printable by 2 cm, the width is printable width and the white solid is 2 cm by the print direction, and the width is printable by repeating the printable width from the beginning to the end of the A4 paper. 10,000, 50,000 and 100,000 copies were made. Next, a halftone image of 1 dot × 1 dot was output in an environment of 30 ° C. and 90% humidity using A3 paper that was left for 3 hours in an environment of 30 ° C. and 90% humidity. , The portion corresponding to the portion where black solid was repeated and the portion where white solid was repeated were measured using a reflection densitometer (Macbeth densitometer), and the darkest portion corresponding to the portion where black solid was repeated, The thinnest portion corresponding to the portion where white solid was repeated was measured with a reflection densitometer (Macbeth densitometer), and the difference ΔID was obtained. ΔID was evaluated in five stages according to the following criteria. It should be noted that the state where no filming occurs is an equivalent value, and the larger the value, the worse the halftone unevenness. Also, filming is more disadvantageous as the number of running sheets increases.
A: 0.05 or less,
○: 0.06 to 0.1
□: 0.11 to 0.25,
Δ: 0.26 to 0.4
X: 0.41 or more.

(3) Toner scattering and sleeve fixation Image development (image density measurement), toner scattering [visually observed at the initial stage and after 100K sheets (100,000 sheets) run at 5000 sheets / day after development with a remodeling machine imagio MF7070 manufactured by Ricoh. Evaluation] and sleeve fixation [visual evaluation] were evaluated. The evaluation results were ranked in the following five levels.
◎: Very good, ○: Good, □: Normal, △: Bad, ×: Very bad

(4) Evaluation of heat-resistant storage stability 20 g of a toner sample is put in a 20 ml glass bottle and left in a high-temperature bath at 60 ° C. for 4 hours, and then the penetration is measured by a penetration test (JIS K2235-1991). It was evaluated as follows.
A: 10 mm or more,
○: 9.9-5 mm,
Δ: 4.9-3 mm,
X: 2.9-0 mm.

(5) Durability evaluation A developer is set in MF-2200 manufactured by Ricoh Co., Ltd., and 100,000 continuous images are output in a normal temperature / humidity environment. It was evaluated with.
4: There is no significant change in charge amount and image quality compared to the initial level 3: Although the charge amount is reduced compared to the initial level, there is no significant change in image quality 2: Stain is generated but there is no practical problem Level 1 : Practical level of soiling occurs

  In Table 3, the fine particle content of 0.6 to 2 μm corresponds to the small particle ratio referred to in the present invention.

  As shown in Table 3, with respect to Examples 1 to 5, the evaluation results of low temperature fixability, hot offset resistance, filming, sleeve fixing, toner scattering, heat resistant storage stability, and durability were good. In Comparative Examples 1 and 2, particles consisting only of a release agent were observed, which deteriorated filming, sleeve fixing, toner scattering, heat resistant storage stability and durability.

  The toner production method of the present invention and the toner produced thereby can be used as a developer for developing an electrostatic charge image in electrophotography, electrostatic recording, electrostatic printing, and the like. Specifically, It can be used for a copying machine, a laser printer, a plain paper fax machine, etc. using a direct or indirect electrophotographic developing system.

It is a figure for demonstrating the dispersion apparatus which can be used at the mixing process in this invention.

Explanation of symbols

2 Mixture 3 Drive motor 4 Raw material tank 5 Circulation motor

Claims (8)

In a toner production method in which toner containing at least a release agent is granulated in an aqueous system,
A release agent dispersion forming step for dispersing the release agent in a solvent, a mixing step for mixing the release agent dispersion and another toner composition, and a granulation step for granulating the resulting mixture in an aqueous system It has a door,
The release agent has a softening point Tm of 68-80 ° C, and
In the mixing step, the temperature of the entire region in the mixing system is controlled to (Tm- 30) ° C. or lower ,
The percentage of small particles having an equivalent circle diameter of 0.6 to 2 μm is 5% or less.
Method for producing a toner, characterized in that. The method for producing a toner according to claim 1, wherein the mixing step is performed in an organic solvent phase, and the toner composition contains at least a binder resin and a pigment. The method for producing a toner according to claim 2 , wherein the binder resin contains at least a modified polyester (i) having a reactive substituent. 4. The toner production method according to claim 3 , wherein the reactive substituent of the modified polyester (i) is an isocyanate group. Toner characterized in that it is manufactured by the method according to any one of claims 1-4. The toner according to claim 5 , wherein the degree of aggregation is 3 to 20%. The toner according to claim 5 or 6 volume average particle diameter (Dv) is 3 to 8 [mu] m. The toner according to any one of claims 5-7 the ratio of the volume average particle diameter (Dv) to the number average particle diameter (Dn) (Dv / Dn) is characterized in that it is a 1.00 to 1.2.

Images