JP2007083097A - Resin particle-dispersed solution, electrostatic charge image developing toner, their producing methods, developer, and image forming method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resin particle-dispersed solution which is obtained by emulsifying/dispersing resin particles stably in an aqueous medium by low energy and to provide an electrostatic charge image developing toner or the like using the resin particle-dispersed solution. <P>SOLUTION: The resin particle-dispersed solution is characterized in that the resin particles are dispersed, each of which has a two-layer structure which consists of a crystalline condensation-polymerized resin/an amorphous condensation-polymerized resin and is composed of an inner core containing the crystalline condensation-polymerized resin and a coated layer in which a part or the whole of the inner core is coated with the amorphous condensation-polymerized resin. The crystalline condensation-polymerized resin and/or the amorphous condensation-polymerized resin are obtained by condensation polymerization in the aqueous medium. The average thickness of the cover layers is 0.01-1.0 μm. The median diameter of the inner cores is 0.01-1.0 μm. The median diameter of the resin particles is 0.02-2.0 μm. A method for producing the resin particle-dispersed solution, the electrostatic charge image developing toner using the resin particle-dispersed solution, a method for producing the electrostatic charge image developing toner, an electrostatic charge image developer and an image forming method are provided. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an electrostatic image developing toner used when developing an electrostatic latent image formed by an electrophotographic method or an electrostatic recording method with a developer, a manufacturing method thereof, and a resin particle dispersion used as a raw material thereof And a manufacturing method thereof, a developer using the toner, and an image forming method.

  A method of visualizing image information through an electrostatic charge image such as electrophotography is currently used in various fields. In electrophotography, an electrostatic charge image is formed on a photoreceptor by charging and exposure processes, the electrostatic latent image is developed with a developer containing toner, and visualized through a transfer and fixing process. As the developer used here, there are known a two-component developer composed of a toner and a carrier and a one-component developer using a magnetic toner or a non-magnetic toner alone. A kneading and pulverizing method is used in which a resin is melt-kneaded together with a release agent such as a pigment, a charge control agent and wax, and after cooling, is finely pulverized and classified. These toners have been used by adding inorganic and organic fine particles to the toner particle surfaces to improve fluidity and cleaning properties if necessary.

On the other hand, in recent years, a technology capable of fixing at a lower temperature is desired in order to reduce energy consumption. Particularly in recent years, in order to thoroughly save energy, the energization of the fixing machine is stopped except during use. It is desired. Accordingly, the temperature of the fixing device needs to be energized and instantaneously raised to the operating temperature. For this purpose, it is desirable to make the heat capacity of the fixing machine as small as possible. In that case, however, the temperature fluctuation of the fixing machine tends to be larger than before. That is, the overshoot of the temperature after the start of energization increases, and on the other hand, the temperature drop due to the paper passing also increases. Further, when paper having a width smaller than the width of the fixing machine is continuously passed, the temperature difference between the paper passing portion and the non-paper passing portion also increases. In particular, when used in a high-speed copying machine or printer, the power supply capacity tends to be insufficient, and the above-mentioned phenomenon tends to occur. Accordingly, there is a strong demand for an electrostatic charge image developing toner having a wide fixing latitude that can be fixed at a low temperature and does not cause an offset to a higher temperature region.
However, lowering the fixing temperature of the toner also lowers the glass transition point (Tg) of the toner at the same time, making it difficult to achieve compatibility with the storage stability of the toner. In order to achieve both low-temperature fixability and toner storage stability, it is necessary to have a so-called sharp melt property in which the viscosity of the toner sharply decreases in a high-temperature region while keeping the glass transition point of the toner higher. is there.

As a means for lowering the toner fixing temperature, a technique for lowering the glass transition point of toner resin (binder resin) is generally used. However, if the glass transition point is too low, toner powder aggregation (blocking) tends to occur, and the storage stability on a fixed image is deteriorated. Therefore, the lower limit of the glass transition point of the toner is practically around 60 ° C.
Although this glass transition point is an important design point of many commercially available toner resins, at present, it is possible to obtain a toner that can be fixed at low temperature by simply lowering the glass transition point of the resin. I could not.

In addition, although the fixing temperature can be lowered by using a plasticizer, there is a problem that blocking easily occurs during storage or in the developing machine.
Therefore, as means for achieving both low-temperature fixability, sharp melt properties, and blocking prevention, as a binder resin constituting the toner, a crystalline polyester is used as a polycondensation type polyester exhibiting sharp melting behavior with respect to temperature. The technique used for is proposed.
This crystalline resin is difficult to pulverize by the melt-kneading pulverization method and cannot be generally used, and a toner production method by an emulsion polymerization aggregation method has been proposed. In this emulsion polymerization aggregation method, a resin particle dispersion is prepared by emulsion polymerization or the like, while a colorant dispersion in which a colorant is dispersed in a solvent is prepared and mixed to form an aggregate corresponding to the toner particle size. In this method, the toner is fused and united by heating.

As described above, a toner prepared using a crystalline resin is excellent in low-temperature fixability and sharp melt properties, but may cause a blocking phenomenon in a developing device or the like even at room temperature, or may have poor frictional chargeability and fluidity. Since the developability is poor, there is a problem that an image obtained is unclear with a lot of fog.
Furthermore, since the toner is soft, a filming phenomenon occurs in which the toner particles adhere to the carrier particles and the surface of the photoconductor by a large number of copies, and further fused to a cleaning member such as a cleaning blade. However, there was also a problem that there was a lot of fogging and the density became unclear.

For this reason, a toner composed only of a crystalline resin cannot practically be established. Therefore, studies have been made to produce a toner by mixing an amorphous resin.
For example, in Patent Document 1, as a method for obtaining a resin for toner, terephthalic acid, isophthalic acid, trimellitic anhydride, polyoxypropylene (2.4) -2,2-bis (4-hydroxyphenyl) are used as monomers. ) Reacted under normal pressure nitrogen flow using propane (BPA-PO), polyoxyethylene (2.4) -2,2-bis (4-hydroxyphenyl) propane (BPA-EO), ethylene glycol, etc. Thereafter, a reaction is performed under reduced pressure to prepare a polyester, and after melt-kneading with a colorant, wax, etc., the melt-kneaded product is heated to 190 ° C. and applied to a dispersion emulsifier to obtain a dispersion after dispersion. A method for producing a toner for developing an electrostatic charge image, characterized in that an aggregate of the resin fine particles is produced by aggregating and further fusing the resin fine particles It has been.
In this method, the energy during resin production and resin emulsification is high, and the environmental burden is enormous, making it not practically usable, and emulsification and dispersion at high temperatures and high shear tends to cause decomposition of the resin. This causes problems such as the occurrence of uneven distribution of the composition and the difficulty of realizing the uniformity of the particle size distribution of the resin particles in the dispersion. In the toners using these materials, the initial image quality is of course continuous. There is a problem that image quality stability during printing is likely to cause problems.

As another method to compensate for the above-mentioned drawbacks of the crystalline polycondensation resin, a method of preparing a toner using a resin obtained by combining a crystalline resin and an amorphous resin in combination with an amorphous vinyl resin has been studied. ing.
For example, in Patent Document 2, an emulsion composite resin composition of polyester and vinyl is prepared by polymerizing a mixture of vinyl monomers in the presence of a water-soluble polyester resin having a hydrophilic group in the molecule. Yes. According to this example, by using vinyl silanes or glycidyl group-containing vinyl monomers as vinyl polymerizable monomers, the polyester resin and vinyl resin are grafted or internally crosslinked to obtain composite particles. It states that it is possible. Further, in this example, since the polyester is limited to water solubility, there is a problem that the toner performance cannot be expressed with good reproducibility from the viewpoint of chargeability and the like.

In addition, as described above, in order to obtain such a polyester resin by polycondensation, it is usually performed under high heat of 200 ° C. or higher and for a long time under stirring and under reduced pressure, which requires a large amount of energy consumption. Become. For this reason, the reaction equipment is required to have high durability, and the capital investment is often excessive.
Also, when emulsifying the obtained resin in water, inefficiency such as emulsification at high shear at 150 ° C. or higher, or removing the solvent after dissolving the solution that has been dissolved in the solvent to reduce viscosity In addition, there is a problem that a process requiring large energy consumption is required.

However, on the other hand, a report that polycondensation of polyester in water is possible (see Patent Document 3).
If polycondensation of polyester in water is possible, polycondensation at 100 ° C. or lower is achieved, so that the above-described polymerization under high heat and reduced pressure is not required, and emulsification at high temperature / high shear is unnecessary. There is an advantage that energy consumption can be greatly reduced compared to the normal manufacturing method.

Since such a polycondensable resin in water polycondensation method has become possible, and as another method for producing polyester / vinyl composite particles, a mini-emulsion polymerization method capable of polycondensation in water seems to be used. It has become.
The mini-emulsion polymerization method referred to here is a method in which, for example, an oil phase in which polyester and vinyl monomer are dissolved is emulsified in water together with an activator and polymerized.
There have been many studies in which toner particles are produced using the resin particles produced by the miniemulsion polymerization method.
For example, Patent Document 4 invents a method for producing a toner for developing an electrostatic charge image, in which colorant-containing polymer fine particles obtained by miniemulsion polymerization of a monomer and a colorant are aggregated.
Further, Patent Document 5 invents a toner in which resin fine particles produced by mini-emulsion polymerization are included in a layer other than the outermost layer and the resin fine particles obtained by multistage polymerization are salted out / fused.
In this method, a high molecular weight vinyl resin is used as the innermost shell (core), a polyester-containing intermediate vinyl layer is formed on the outer side (intermediate layer) by a mini-emulsion polymerization method, and vinyl outer layer is further formed on the outermost outer shell layer. The resin particles themselves have a multi-layer structure by a method of forming a system resin layer.
In this example, several layers are laminated using a vinyl-based resin, and the aim is to achieve the problems caused by the softness and mechanical strength of crystalline polyester.

However, such a method of compounding a vinyl resin can compensate for problems such as weak mechanical strength and low chargeability of crystalline polyester, while improving sharp melt properties. In addition to damage, there are problems that the image glossiness is lowered and the minimum fixing temperature for obtaining good image quality is increased.
For this reason, it is preferable to use an amorphous polycondensation resin for the outer shell layer covering the crystalline polycondensation resin.
However, in the prior art, although there is an examination example of producing a toner resin by using a crystalline polycondensation resin and an amorphous polycondensation resin in combination, the crystalline polycondensation resin is used as the inner shell (core). Patent Document 6 is the only study example using an amorphous polycondensation resin for the outer layer (shell) covering the crystalline resin.
Furthermore, as a method to compensate for the disadvantages of crystalline polyester, the double-layer structure particles were obtained by preparing a polycondensable resin occupying the structure using an underwater polycondensation method, and adapted to a toner resin. There are no examples yet.

JP 2002-351140 A JP-A-7-207219 U.S. Pat. No. 4,355,154 JP 2001-290308 A JP 2002-49180 A JP 2005-215298 A

Accordingly, an object of the present invention is to solve the conventional problems and achieve the following object.
That is, an object of the present invention is to provide a resin particle dispersion in which resin particles are stably emulsified and dispersed in an aqueous medium with low energy.
Another object of the present invention is to produce an electrostatic image developing toner that can be used to produce an electrostatic image developing toner that sufficiently satisfies the toner characteristics and provides performance that does not change over a long period of time. It is an object to provide a method, an electrostatic image developing toner obtained by the method, a developer using the toner, and an image forming method.

The above-described problems of the present invention have been solved by the following means <1>, <2>, <9>, <10>, <12> and <13>. It describes below with <3>-<8> and <11> which are preferable embodiments.
<1> (1) Two layers of crystalline resin / noncrystalline resin comprising an inner core containing a crystalline polycondensation resin and a coating layer in which the amorphous polycondensation resin covers part or all of the inner core A resin particle dispersion in which resin particles having a structure are dispersed, (2) a resin obtained by polycondensation of the crystalline resin and / or the amorphous resin in an aqueous medium, (3) the resin The average layer thickness of the coating layer is 0.01 μm or more and 1.0 μm or less, (4) the median diameter of the inner core is 0.01 μm or more and 1.0 μm or less, and (5) crystalline resin / non-crystalline resin A resin particle dispersion, wherein the median diameter of the resin particles having a two-layer structure is 0.02 μm or more and 2.0 μm or less,
<2> A step of obtaining a crystalline resin particle dispersion in which resin particles containing a crystalline polycondensation resin are dispersed in an aqueous medium, and a single unit for producing an amorphous resin in the obtained crystalline resin particle dispersion. <1> including a step of adding a dispersion emulsion in which a monomer is dispersed and polycondensing to obtain a resin particle dispersion in which resin particles in which an inner core is a crystalline resin and a coating layer is an amorphous resin are dispersed. A method for producing the resin particle dispersion according to claim 1,
<3> The method for producing a resin particle dispersion according to <2>, wherein an acid having a surfactant effect is used as the polycondensation catalyst,
<4> The resin particle dispersion according to <1>, wherein the monomer and the crystalline resin that form the amorphous resin satisfy the following formula (I):
δma ≧ δpc Formula (I)
(In the formula (I), δma represents the solubility parameter ((cal / cc) ^1/2 ) of the monomer that forms the amorphous resin at 25 ° C., and δpc represents the solubility parameter of the crystalline resin at 25 ° C. ( (Cal / cc) ^1/2 )
<5> The resin particle dispersion according to <1>, wherein the monomer that generates the crystalline resin and the monomer that generates the amorphous resin each include at least a polyol and a polyvalent carboxylic acid,
<6> The weight ratio of the crystalline resin and the amorphous resin in the resin particles having a two-layer structure of crystalline resin / noncrystalline resin is 5/95 to 95/5, Resin particle dispersion,
<7> The resin particle dispersion according to <1>, wherein the crystalline resin has a crystalline melting point of 50 ° C. or higher and lower than 120 ° C.,
<8> The resin particle dispersion according to <1>, wherein the glass transition point of the amorphous resin is 45 ° C. or higher and lower than 80 ° C.
<9> A method for producing an electrostatic charge image developing toner, comprising: a step of aggregating the resin particles in a dispersion containing at least a resin particle dispersion to obtain aggregated particles; and a step of heating and aggregating the aggregated particles. The resin particle dispersion is the resin particle dispersion according to the above <1> or <4> to <8>, or the resin produced by the production method according to the above <2> or <3>. A method for producing an electrostatic charge image developing toner, which is a particle dispersion;
<10> An electrostatic charge image developing toner produced by the production method according to <9>,
<11> The electrostatic charge image developing toner according to <10>, wherein a cumulative volume average particle size of the electrostatic charge image developing toner is 3.0 μm or more and 10.0 μm or less.
<12> An electrostatic charge image developer comprising the electrostatic charge image developing toner according to <10> and a carrier,
<13> A latent image forming step for forming an electrostatic latent image on the surface of the latent image holding member, and developing the electrostatic latent image formed on the surface of the latent image holding member with a developer containing toner to form a toner image. An image development process, a transfer process for transferring the toner image formed on the surface of the latent image carrier to the surface of the transfer target, and a fixing process for thermally fixing the toner image transferred to the surface of the transfer target. A method for forming an image, wherein the electrostatic image developing toner according to <10> is used as the toner, or the electrostatic image developer according to <12> is used as the developer. .

Since the conventional resin particle dispersion containing a polycondensable resin was difficult to polymerize in an aqueous medium, it had a great environmental impact in production. A resin particle dispersion in which resin particles are stably emulsified and dispersed can be provided.
In addition, in order to compensate for the weakness of mechanical strength and the drawbacks of chargeability / developability when a crystalline polycondensation resin is used in the toner, a crystalline / noncrystalline polycondensation resin is combined to form an inner core (hereinafter, “ A crystalline polycondensation resin in the core)), and resin particles in which an amorphous polycondensation resin is formed as a coating layer so as to cover the core on the outside of the resin. It is possible to provide an electrostatic image developing toner having sharp melt properties and high image gloss, which could not be achieved in the past while ensuring the low temperature fixability.

Hereinafter, the present invention will be described in detail.
(Resin particle dispersion)
The resin particle dispersion of the present invention comprises (1) a coating layer (hereinafter referred to as “outer layer”, “outer layer”, wherein the inner core containing a crystalline polycondensation resin and a non-crystalline polycondensation resin cover part or all of the inner core. A resin particle dispersion in which resin particles having a two-layer structure of crystalline resin / amorphous resin consisting of “outer shell layer” or “shell” are dispersed, wherein (2) the crystalline resin and / Or a resin obtained by polycondensation of the amorphous resin in an aqueous medium, (3) the coating layer has an average layer thickness of 0.01 μm to 1.0 μm, and (4) the inner core The median diameter of the resin particles having a median diameter of 0.01 μm or more and 1.0 μm or less and (5) a crystalline resin / non-crystalline resin two-layer structure (hereinafter also referred to as “core / shell structure”). It is 0.02 μm or more and 2.0 μm or less. In the present invention, the resin particles having a two-layer structure of crystalline resin / non-crystalline resin may be simply referred to as “resin particles”.
Although there is no restriction | limiting in particular about the manufacturing method, it is preferable that the resin particle dispersion liquid of this invention is manufactured with the below-mentioned manufacturing method.
The resin particle dispersion of the present invention is preferably used as a resin particle dispersion for an electrostatic charge image developing toner.
The inner core of the resin particles only needs to contain at least a crystalline polycondensation resin (also simply referred to as “crystalline resin”), and a monomer for generating a crystalline resin (hereinafter simply referred to as “crystalline resin unit”). It is preferable to include at least a crystalline resin obtained by polycondensation in a water-based medium, and further include two or more crystalline resins, other resins, various additives, and the like. May be.
The outer layer of the resin particles only needs to contain at least a non-crystalline polycondensation resin (also simply referred to as “non-crystalline resin”), and a monomer (hereinafter simply referred to as “non-crystalline resin”). It is preferable to include at least a crystalline resin obtained by polycondensation in a water-based medium, and more than two types of amorphous resins and other resins, The additive may be included.
By polycondensing a crystalline resin and / or an amorphous resin in an aqueous medium, a resin particle dispersion can be obtained more easily and with lower energy than conventional methods.

In general, since the polycondensation reaction involves dehydration during polymerization, in principle, it does not proceed in an aqueous medium, particularly in water. However, by emulsifying the polycondensable monomer as a monomer droplet in water with a certain surfactant, the monomer is placed in a micro hydrophobic field in the monomer droplet, resulting in a dehydration action and generation. It has been reported that the water discharged into the water outside the monomer droplets can proceed to the polymerization.
In the resin particle dispersion of the present invention, the polycondensation of crystalline polyester or amorphous polyester in an aqueous medium is carried out by subjecting the polyester monomer to a polycondensation reaction in an aqueous medium. It is possible to increase the molecular weight, and it is also possible to mix an acid having a surfactant effect and a polycondensation catalyst together with the monomer component in the monomer.
The method for producing the crystalline resin and the amorphous resin in the present invention is not particularly limited, but is a method in which at least one resin is directly polycondensed in an aqueous medium, and the amorphous resin is in an aqueous medium. Direct polycondensation is preferable, and it is particularly preferable that the crystalline resin and the amorphous resin are directly polycondensed in an aqueous medium.
The crystalline resin and the non-crystalline resin are preferably polyesters, and the polyester monomer component more preferably contains at least a polyvalent carboxylic acid and a polyol.

Polycondensation type polyesters that can be used in the present invention include, for example, aliphatic, alicyclic and aromatic polyvalent carboxylic acids, their alkyl esters and polyhydric alcohols, their ester compounds, and hydroxycarboxylic acids. It can be prepared by polycondensation by direct esterification reaction, transesterification reaction or the like in an aqueous medium using a condensable monomer.
In this case, the polyester resin produced by polycondensation takes any form of amorphous polyester (also referred to as “amorphous polyester”), crystalline polyester, or a mixed form thereof. be able to.
“Crystallinity” as shown in the above “crystalline polyester resin” means that, in differential scanning calorimetry (DSC), it has a clear endothermic peak, not a stepwise endothermic change. Means that the half-value width of the endothermic peak when measured at a heating rate of 10 ° C./min is within 6 ° C.
On the other hand, a resin having an endothermic peak with a half-value width exceeding 6 ° C. or a resin having no clear endothermic peak means non-crystalline (amorphous).

<Polyester monomer>
In the polyester that can be used in the present invention, the polyvalent carboxylic acid that can be used as the polycondensable monomer is a compound containing two or more carboxyl groups in one molecule. Among these, dicarboxylic acid is a compound containing two carboxyl groups in one molecule. For example, oxalic acid, glutaric acid, succinic acid, maleic acid, adipic acid, β-methyladipic acid, azelaic acid, sebacic acid, Nonanedicarboxylic acid, decanedicarboxylic acid, undecanedicarboxylic acid, dodecanedicarboxylic acid, fumaric acid, citraconic acid, diglycolic acid, cyclohexane-3,5-diene-1,2-carboxylic acid, malic acid, citric acid, hexahydroterephthalate Acid, malonic acid, pimelic acid, tartaric acid, mucoic acid, phthalic acid, isophthalic acid, terephthalic acid, tetrachlorophthalic acid, chlorophthalic acid, nitrophthalic acid, p-carboxyphenylacetic acid, p-phenylenediacetic acid, m-phenylenediglycol Acid, p-phenylene diglycolic acid, o-phenylene Glycolic acid, diphenylacetic acid, diphenyl-p, p′-dicarboxylic acid, naphthalene-1,4-dicarboxylic acid, naphthalene-1,5-dicarboxylic acid, naphthalene-2,6-dicarboxylic acid, anthracene dicarboxylic acid, cyclohexanedicarboxylic acid Etc. Examples of the polyvalent carboxylic acid other than dicarboxylic acid include trimellitic acid, pyromellitic acid, naphthalenetricarboxylic acid, naphthalenetetracarboxylic acid, pyrenetricarboxylic acid, and pyrenetetracarboxylic acid. Moreover, you may use what derived the carboxyl group of these carboxylic acid to the acid anhydride, mixed acid anhydride, acid chloride or ester.

The polyol that can be used in the present invention is a compound containing two or more hydroxyl groups in one molecule. Among these, diol is a compound containing two hydroxyl groups in one molecule, and examples thereof include ethylene glycol, propylene glycol, butanediol, diethylene glycol, hexanediol, cyclohexanediol, octanediol, decanediol, dodecanediol and the like. Can do. Examples of polyols other than diols include glycerin, pentaerythritol, hexamethylol melamine, hexaethylol melamine, tetramethylol benzoguanamine, and tetraethylol benzoguanamine.
Since these polyols are hardly soluble or insoluble in the aqueous medium, the ester synthesis reaction proceeds in the monomer droplets in which the polyol is dispersed in the aqueous medium.

In the present invention, examples of the hydroxycarboxylic acid that can be used as the polycondensable monomer include hydroxyheptanoic acid, hydroxyoctanoic acid, hydroxydecanoic acid, and hydroxyundecanoic acid.
The polycondensation resin that can be used in the present invention can easily obtain an amorphous resin or a crystalline resin by a combination of these polycondensable monomers.

(Crystalline polyester)
As the polyvalent carboxylic acid used to obtain the crystalline polyester, among the above carboxylic acids, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, peric acid, azelaic acid, sebacic acid, Maleic acid, fumaric acid, citraconic acid, itaconic acid, glutamic acid, n-dodecyl succinic acid, n-dodecenyl succinic acid, isododecyl succinic acid, isododecenyl succinic acid, n-octyl succinic acid, n-octenyl succinic acid, these And acid anhydrides or acid chlorides thereof.

  Examples of the polyol used to obtain the crystalline polyester include ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,4, Examples include butenediol, neopentyl glycol, 1,5-pentane glycol, 1,6-hexane glycol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, dipropylene glycol, polyethylene glycol, polypropylene glycol and the like. it can.

  Examples of such crystalline polycondensation resins include polyesters obtained by reacting 1,9-nonanediol and 1,10-decanedicarboxylic acid, or cyclohexanediol and adipic acid, 1,6-hexanediol and sebacin. Polyester obtained by reacting acid, polyester obtained by reacting ethylene glycol and succinic acid, polyester obtained by reacting ethylene glycol and sebacic acid, reacting 1,4-butanediol and succinic acid The polyester obtained by doing this can be mentioned. Among these, polyesters obtained by reacting 1,9-nonanediol and 1,10-decanedicarboxylic acid, and 1,6-hexanediol and sebacic acid are more preferable.

[Amorphous polyester]
In addition, as the polyvalent carboxylic acid used to obtain the non-crystalline polyester in the present invention, among the above polyvalent carboxylic acids, as the dicarboxylic acid, phthalic acid, isophthalic acid, terephthalic acid, tetrachlorophthalic acid, Chlorphthalic acid, nitrophthalic acid, p-carboxyphenylacetic acid, p-phenylenediacetic acid, m-phenylenediglycolic acid, p-phenylenediglycolic acid, o-phenylenediglycolic acid, diphenylacetic acid, diphenyl-p, p'-dicarboxylic Examples include acid, naphthalene-1,4-dicarboxylic acid, naphthalene-1,5-dicarboxylic acid, naphthalene-2,6-dicarboxylic acid, anthracene dicarboxylic acid, and cyclohexanedicarboxylic acid. Examples of the polyvalent carboxylic acid other than dicarboxylic acid include trimellitic acid, pyromellitic acid, naphthalenetricarboxylic acid, naphthalenetetracarboxylic acid, pyrenetricarboxylic acid, and pyrenetetracarboxylic acid. Moreover, you may use what derived the carboxyl group of these carboxylic acid to the acid anhydride, the acid chloride, or ester.
Among these, it is preferable to use terephthalic acid or its lower ester, diphenylacetic acid, cyclohexanedicarboxylic acid, or the like. The lower ester refers to an ester of an aliphatic alcohol having 1 to 8 carbon atoms.

Moreover, as a polyol used in order to obtain the amorphous polyester in this invention, it is especially using polytetramethylene glycol, bisphenol A, bisphenol Z, hydrogenated bisphenol A, cyclohexane dimethanol, etc. among the said polyols. preferable.
In addition, an amorphous resin or a crystalline resin can be easily obtained by combining the above polycondensable monomers.
In order to produce one type of polycondensation resin, each of the polyvalent carboxylic acid and polyol may be used alone or in combination of two or more, each of which may be used alone or in combination of two or more. You may use each. Moreover, when using hydroxycarboxylic acid in order to produce 1 type of polycondensation resin, 1 type may be used individually, 2 or more types may be used, and polyvalent carboxylic acid and a polyol may be used together.

<Aqueous medium>
In the present invention, the dispersion medium of the resin particle dispersion is an aqueous medium. The crystalline resin contained in the inner core and the amorphous resin contained in the outer layer are resins obtained by polycondensation in an aqueous medium.
Examples of the aqueous medium that can be used in the present invention include water such as distilled water and ion exchange water, and alcohols such as ethanol and methanol. Among these, ethanol and water are preferable, and water such as distilled water and ion-exchanged water is particularly preferable. These may be used alone or in combination of two or more.
The aqueous medium may contain a water-miscible organic solvent. Examples of the water-miscible organic solvent include acetone and acetic acid.

<Characteristics of resin and resin particles>
In the resin particle dispersion of the present invention, as a method for analyzing the structure of the resin particles having a two-layer structure in which the crystalline resin is an inner core and the amorphous resin covering the inner core is a shell layer, basically, This can be confirmed by a cross-sectional TEM (transmission electron microscope) (JEOL 1010) using an osmium oxide staining method or the like. In the TEM photograph obtained by observation, a difference in contrast occurs between the crystalline resin portion and the amorphous resin portion, so that each phase can be identified.
The thickness of the non-crystalline resin layer (outer layer) can be determined by measuring the thickness of the outer layer portion of particles having different contrast in the particles and converting the scale from the TEM photograph using the above dyeing method.
The calculation method of the thickness of the outer layer portion of the resin particle in the present invention is obtained by converting the thickness of the outer layer (shell) at five locations per each particle for any 10 particles in the photographed TEM photograph, and averaging the values. It is calculated by using.
The average layer thickness of the outer layer of the amorphous resin in the present invention is 0.01 to 1.0 μm, and preferably 0.01 to 0.1 μm. It is preferable that the average thickness of the outer layer is 0.01 μm or more because the properties of the crystalline resin do not dominate in the core / shell particles and the charging performance and mechanical strength are excellent. Moreover, it is preferable that the average thickness of the outer layer is 1.0 μm or less because the characteristics of the amorphous resin do not dominate in the core / shell particles, and the chargeability, low-temperature fixability, and sharp melt properties are excellent. .

The median diameter (center diameter) of the inner core containing the crystalline resin in the present invention is 0.01 to 1.0 μm, and preferably 0.01 to 0.1 μm.
When the median diameter of the inner core is 0.01 μm or more, it is effective because it is easy to obtain the effect of fixing the resin constituting the inner core at the time of fixing, and when the median diameter of the inner core is 1.0 μm or less, Due to agitation stress in the developing machine, toner crushing does not occur, the mechanical strength is strong, and even when printing as a printer at high temperature and high humidity, charge leakage does not occur, so the charge does not decrease, so the temperature is high. This is preferable because high image quality can be maintained even when printing at high humidity.
The median diameter of the inner core is, for example, during the production of resin particles having a core / shell structure, that is, at the stage where only the core particles are produced, using a laser diffraction particle size distribution measuring device (Horiba, LA-920) or the like. Alternatively, the median diameter of the inner core may be measured by the above-mentioned method by removing the outer layer portion from the resin particles having a core / shell structure by a mechanical method or a chemical method to form particles only of the inner core.
Further, for example, from a TEM photograph using a staining method such as the osmium oxide staining method as described above, at least 50 inner cores of particles having different contrasts in the particles are measured, and the particle size is obtained by converting the scale. The median diameter of the inner core may be obtained.

The center diameter (median diameter) of the resin particles having a core / shell structure dispersed in the resin particle dispersion of the present invention thus obtained is 0.02 μm or more and 2.0 μm or less, preferably 0.8. A range of 05 to 2.0 μm, more preferably 0.1 to 1.5 μm, and still more preferably 0.1 to 1.0 μm is appropriate. When the median diameter of the resin particles is 0.02 μm or more, the cohesiveness at the time of particle formation is good, free resin particles are hardly generated, the viscosity of the system is not easily increased, and the particle diameter can be easily controlled. Therefore, it is preferable. Further, when the median diameter of the resin particles is 2.0 μm or less, coarse powder is hardly generated, the particle size distribution is good, the release agent such as wax is difficult to be released, the releasability at fixing is excellent, and the offset This is preferable because the generation temperature does not decrease.
The median diameter of the resin particles having a core / shell structure can be measured by a laser diffraction type particle size distribution measuring apparatus (Horiba, LA-920).

  In addition to the center diameter of the resin particles in the resin particle dispersion, it is also important that there is no generation of ultrafine powder or ultracoarse powder. The ratio of particles of 0.01 μm or less or 5.0 μm or more (hereinafter, “ Also referred to as “large / small particle total ratio”) is preferably 10% or less, more preferably 5% or less.

Further, in order to produce resin particles having a two-layer structure in the present invention, the resin structure has an outer shell layer in which a crystalline resin exists in the inner core and covers a part or all of the crystalline resin. It is preferable to show a structure that becomes an amorphous resin.
Moreover, it is preferable that the ratio of the resin of crystalline resin and non-crystalline resin becomes crystalline resin / non-crystalline resin = 5 / 95-95 / 5. When the ratio of the crystalline resin to the amorphous resin is crystalline resin / non-crystalline resin = (95/5) or less, the chargeability and mechanical strength are sufficient when the toner is produced, and the image It is preferable because of its excellent quality. In addition, when the ratio of the crystalline resin to the amorphous resin is greater than or equal to the crystalline resin / noncrystalline resin = (5/95), the toner is excellent in low-temperature fixability and sharp melt properties. preferable.

Further, in the present invention, the difference in hydrophilicity between the crystalline resin and the amorphous resin monomer, that is, the solubility parameter (SP value) difference between the crystalline resin and the amorphous resin monomer. It has been found that by utilizing the difference, it is possible to easily produce resin particles having the above-described structure.
Here, the method for calculating the solubility parameter of the crystalline resin and the amorphous resin monomer is the most general-purpose method proposed by Fedors et al. (RF Fedors, Polym. Eng). Sci., 14, 147 (1974)), that is, a method of determining a sum of cohesive energy Δe _i and a sum of molecular solutions Δv _i for each unit functional group, and obtaining by the following formula (II).
δ = (ΣΔe _i / ΣΔv _i ) ^1/2 formula (II)

In the present invention, at least the solubility parameter δpc of the crystalline resin determined by the above formula is smaller than the solubility parameter δma of the amorphous resin monomer, that is,
δma ≧ δpc Formula (I)
It is preferable that all the amorphous resin monomers to be used satisfy the formula (I), and more preferably satisfy the following (IA).
δma−δpc ≧ 0.5 Formula (IA)

What the formula (I) means is that the amorphous resin resin monomer is sufficiently hydrophilic than the already formed crystalline resin.
If the solubility parameters δpc and δma do not satisfy the formula (I), the probability that an amorphous resin monomer is present on the surface of the crystalline resin is greatly reduced when forming a coating layer in an aqueous medium. However, since the non-crystalline resin monomer is likely to be dispersed almost uniformly in the aqueous medium, the resulting particles have a core / shell structure after polycondensation of the non-crystalline resin monomer. In many cases, a dispersed emulsion in which the crystalline resin and the amorphous resin are separately dispersed in the aqueous medium is obtained.
The solubility parameters δpc and δma satisfy the formula (I), that is, the amorphous resin monomer is sufficiently hydrophilic to the crystalline resin, so that the amorphous resin monomer is added to the crystalline resin. Without entering, the amorphous resin monomer is likely to be present on the surface of the more hydrophobic crystalline resin. Under such conditions, the amorphous monomer is polycondensed in an aqueous medium to form a core. 1 shows a structure in which a crystalline resin and an amorphous resin are arranged in the shell layer, and the crystalline resin is preferably partly or entirely covered with the amorphous resin.
As a result, the toner using the resin particle dispersion of the present invention can make up for the weakness of chargeability and mechanical strength, which is a drawback, while ensuring the sharp melt property of the crystalline resin. .
As specific solubility parameter values of the polycondensation resin, for example, the values of Δpc and Δma calculated by the above-mentioned Fador et al. Formula are shown below.
The δpc value of the polyester obtained by polycondensation of 1,6-hexaneol and sebacic acid is 9.20.
The δpc value of the polyester obtained by polycondensation of 1,9-nonanediol and sebacic acid is 9.02.
The δpc value of the polyester obtained by polycondensation of 1,9-nonanediol and 1,12-dodecanedioic acid is 8.92.
The δpc value of the polyester obtained by polycondensation of 1,12-dodecanediol and 1,12-dodecanedioic acid is 8.68.
Further, δma in the monomer is calculated to be 11.57 for the bisphenol A-ethylene oxide 1 mol adduct, 12.50 for terephthalic acid, and 10.15 for dimethyl terephthalate.

The crystalline resin preferably has a crystal melting point of 40 to 150 ° C, more preferably 50 to 120 ° C, and particularly preferably 55 to 110 ° C. When the crystalline melting point of the crystalline resin to be used is 40 ° C. or higher, the resulting toner has good blocking resistance, and when it is 150 ° C. or lower, the melt fluidity at low temperature of the toner is lowered and the fixability is improved. May be worse.
The melting point of the crystalline resin can be measured by, for example, “DSC-20” (manufactured by Seiko Denshi Kogyo Co., Ltd.) according to the differential scanning calorimetry (DSC). It can be determined as the melting peak temperature of the input compensated differential scanning calorimetry shown in JIS K-7121 when the measurement is performed at a temperature rising rate of 10 ° C./min from room temperature to 150 ° C. A crystalline resin may show a plurality of melting peaks, but in the present invention, the maximum peak is regarded as the melting point.

On the other hand, when the polycondensable resin is non-crystalline, the glass transition point Tg is preferably 50 to 80 ° C, and more preferably 50 to 65 ° C. When Tg is 50 ° C. or higher, the cohesive force of the binder resin itself in a high temperature range is good, and hot offset hardly occurs during fixing, and when it is 80 ° C. or lower, sufficient melting is obtained. This is preferable because the minimum fixing temperature does not increase.
Here, the glass transition point of the non-crystalline resin refers to a value measured by a method (DSC method) defined in ASTM D3418-82.
The glass transition point in the present invention can be measured by, for example, “DSC-20” (manufactured by Seiko Denshi Kogyo Co., Ltd.) according to the differential scanning calorimetry (DSC), specifically about 10 mg of a sample. Is heated at a constant rate of temperature increase (10 ° C./min), and the glass transition point can be obtained from the intersection of the baseline and the endothermic peak tilt line.

The weight average molecular weight of the polycondensation resin that can be used in the present invention is preferably 1,500 to 60,000, and more preferably 3,000 to 40,000. When the weight average molecular weight is 1,500 or more, the binder resin has good cohesive strength and excellent hot offset property. When it is 60,000 or less, the hot offset property is excellent and the minimum fixing temperature is increased. This is preferable because it does not occur.
Further, the resin that can be used in the present invention may be partially branched or cross-linked by selecting the carboxylic acid valence or alcohol valence of the monomer, adding a cross-linking agent, or the like.

The values of the weight average molecular weight Mw and the number average molecular weight Mn can be determined by various known methods, and there are some differences depending on the measurement methods, but in the present invention, the values are determined by the following measurement methods. Is preferred. That is, the weight average molecular weight Mw and the number average molecular weight Mn are measured by gel permeation chromatography (GPC) under the conditions described below. At a temperature of 40 ° C., a solvent (tetrahydrofuran) is flowed at a flow rate of 1.2 ml per minute, and 3 mg of a tetrahydrofuran sample solution having a concentration of 0.2 g / 20 ml is injected as a sample weight for measurement. When measuring the molecular weight of a sample, select the measurement conditions that fall within the range in which the logarithm of the molecular weight of the prepared calibration curve and the count number are linear, using several monodisperse polystyrene standard samples. .
In addition, the reliability of the measurement results is that the NBS706 polystyrene standard sample performed under the above measurement conditions is
Weight average molecular weight Mw = 28.8 × 10 ⁴
Number average molecular weight Mn = 13.7 × 10 ⁴
Can be confirmed.
As the GPC column to be used, any column may be adopted as long as it satisfies the above conditions. Specifically, for example, TSK-GEL, GMH (manufactured by Tosoh Corporation) or the like can be used.
In addition, a solvent and measurement temperature are not limited to the conditions described above, You may change to an appropriate condition.

<Additives such as surfactants>
The resin particle dispersion of the present invention may contain additives such as a surfactant, a polymer dispersant, and an inorganic dispersant.
When the polycondensation resin is dispersed and emulsified in an aqueous medium, the above materials are emulsified or dispersed in the aqueous medium using, for example, mechanical shear or ultrasonic waves. An activator, a polymer dispersant, an inorganic dispersant and the like can be added to the aqueous medium. Further, a surfactant, a polymer dispersant, an inorganic dispersant and the like can be mixed and added to the monomer.

Examples of the surfactant that can be used in the present invention include anionic surfactants such as sulfate ester, sulfonate, and phosphate ester; cationic surfactants such as amine salt type and quaternary ammonium salt type. Agents: Nonionic surfactants such as polyethylene glycol, alkylphenol ethylene oxide adducts, polyhydric alcohols, and the like. Among these, anionic surfactants and cationic surfactants are preferable.
The said surfactant may be used individually by 1 type, and may use 2 or more types together. The nonionic surfactant is preferably used in combination with the anionic surfactant or the cationic surfactant.

Anionic surfactants include sodium dodecylbenzenesulfonate, sodium alkylnaphthalenesulfonate, sodium arylalkylpolyethersulfonate, 3,3′-disulfonediphenylurea-4,4′-diazo-bis-amino-8-naphthol Sodium 6-sulfonate, ortho-carboxybenzene-azo-dimethylaniline, 2,2 ′, 5,5′-tetramethyl-triphenylmethane-4,4′-diazo-bis-β-naphthol-6-sulfone Sodium sulfate, sodium dialkylsulfosuccinate, sodium dodecyl sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate, sodium oleate, sodium laurate, sodium caprate, sodium caprylate, capron Examples thereof include sodium acid, potassium stearate, calcium oleate and the like.
Examples of the cationic surfactant include alkylbenzene dimethyl ammonium chloride, alkyl trimethyl ammonium chloride, distearyl ammonium chloride and the like.
Nonionic surfactants include polyethylene oxide, polypropylene oxide, combinations of polypropylene oxide and polyethylene oxide, esters of polyethylene glycol and higher fatty acids, alkylphenol polyethylene oxide, esters of higher fatty acids and polyethylene glycol, higher fatty acids and polypropylene oxide. Examples thereof include esters and sorbitan esters.

Examples of the polymer dispersant include sodium polycarboxylate and polyvinyl alcohol, and examples of the inorganic dispersant include calcium carbonate. However, these do not limit the present invention.
Furthermore, usually, in order to prevent the Ostwald Ripping phenomenon of monomer emulsion particles in an aqueous medium, higher alcohols represented by heptanol and octanol, and higher aliphatic hydrocarbons represented by hexadecane are often used as stabilizing aids. It is also possible to mix.

(Method for producing resin particle dispersion)
The method for producing a resin particle dispersion of the present invention (hereinafter also simply referred to as “method for producing a resin particle dispersion”) is not particularly limited, and is a crystalline resin and / or an aqueous system subjected to polycondensation in an aqueous medium. A known method for producing core / shell type resin particles and core / shell type toners can be used using a non-crystalline resin subjected to polycondensation in a medium, but the resin particles containing a crystalline polycondensation resin can be used as an aqueous medium. A step of obtaining a dispersion of crystalline resin particles dispersed therein (hereinafter also referred to as an “inner core production step”), and a monomer for forming an amorphous resin is added to the dispersion of crystalline resin particles. It is preferable to include a step of condensing and obtaining a resin particle dispersion in which resin particles whose inner core is a crystalline resin and whose coating layer is an amorphous resin are dispersed (hereinafter also referred to as “outer layer manufacturing step”).
As a known method for producing core / shell type resin particles, for example, a method described in JP-A-2005-215298 may be mentioned.
The resin particle dispersion produced by the method for producing a resin particle dispersion of the present invention is preferably used as a resin particle dispersion for an electrostatic charge image developing toner.

In general, in an electrostatic charge image developing toner, when a resin component composed only of a crystalline polycondensable resin is used as a resin component, the low-temperature fixability is excellent, but the charging / mechanical strength is weak. It cannot stand practical use.
Therefore, it is preferable that the resin structure has a structure (core / shell structure) that becomes a non-crystalline polyester resin as an outer shell layer in which the inner core covers a part or all of the crystalline resin and the crystalline resin.
In order to control the resin particles to have the above structure, for example, after preparing a polycondensable resin particle dispersion having crystallinity, a dispersion emulsion in which an amorphous polycondensable resin monomer is dispersed is added. It is preferable that the production method is a procedure for polycondensing an amorphous polycondensable monomer. If a crystalline polycondensable resin monomer and an amorphous polycondensable resin monomer are simultaneously coexisting in the form of a monomer and subjected to polycondensation, the resulting particles cannot have a core / shell structure. . When the core / shell structure cannot be taken, or when the core (inner core) and shell (outer shell layer) are interchanged, the crystalline resin has low chargeability and weak mechanical strength. Since it cannot be compensated, image quality defects are likely to occur when toner is used.

<Inner core manufacturing process>
The method for producing the resin particle dispersion of the present invention is not particularly limited as long as the resin particle dispersion of the present invention can be obtained, but the crystalline resin particles in which resin particles containing a crystalline polycondensation resin are dispersed in an aqueous medium. It is preferable to include a step of obtaining a dispersion (inner core production step). The crystalline polycondensation resin in the inner core production step is more preferably obtained by polycondensing a crystalline resin monomer in an aqueous medium using a polycondensation catalyst.
The crystalline resin particle dispersion is, for example, an aqueous system in which a monomer used for polycondensation is dissolved in a small amount of a surfactant, a polymer stabilizer, etc. as necessary using mechanical shearing force, ultrasonic waves, etc. After emulsifying and dispersing in a medium to prepare a dispersed emulsion containing a crystalline resin monomer, a crystalline resin particle dispersion is obtained by performing polycondensation directly in an aqueous medium using a polycondensation catalyst. Can do.

As a method for preparing the dispersion emulsion, for example, a monomer solution (oil phase) to which a co-surfactant is added and an aqueous solution (aqueous phase) of a surfactant are mixed with a piston homogenizer, a microfluidizer (for example, , Microfluid, “Microfluidizer” manufactured by Dix, Inc.), and a method of uniformly emulsifying and emulsifying using a shear mixing device such as an ultrasonic disperser. If necessary, the monomer solution forming the oil phase may be added with a known organic solvent or the like, and a suspension obtained by suspending the monomer in an aqueous medium or an organic solvent is used. Also good. In that case, it is preferable that the preparation amount of the oil phase with respect to the water phase is about 0.1 to 50% by weight with respect to the total amount of the water phase and the oil phase. The amount of the surfactant used is preferably less than the critical micelle concentration (CMC) in the presence of the emulsion to be formed, and the amount of the cosurfactant used is preferably 100 parts by weight of the oil phase. Is 0.1 to 40 parts by weight, more preferably 0.1 to 20 parts by weight.
In addition, as described above, the polymerization of the monomer in the presence of the polycondensation catalyst of the monomer emulsion by the combined use of the surfactant amount less than the critical micelle concentration (CMC) and the cosurfactant is “mini” The “emulsion polymerization method” is preferable because uniform polymer particles are formed because the monomers are polymerized in the monomer particles (oil droplets). Further, the “miniemulsion polymerization method” has an advantage that the polymer can exist in the polymer particles as it is because diffusion of the monomer is unnecessary in the polymerization process.

  Also, for example, J. Org. S. Guo, M .; S. El-Asser, J.A. W. Vanderhoff; Polym. Sci. : Polym. Chem. Ed. 27, 691 (1989), etc., so-called “microemulsion polymerization” of particles having a particle diameter of 5 to 50 nm has the same dispersion structure and polymerization mechanism as “miniemulsion polymerization” in the present invention. It can be used in the present invention. “Microemulsion polymerization” uses a large amount of a surfactant having a critical micelle concentration (CMC) or more, and a large amount of the surfactant is mixed in the resulting polymer particles or for the removal thereof. In addition, there may be a problem that a great amount of time is required for processes such as water cleaning, acid cleaning, or alkali cleaning.

  In addition, the monomer is dissolved in another medium, and if necessary, an oil phase in which a surfactant, a co-surfactant and the like are dissolved is prepared, dispersed in the aqueous medium, heated, and heated. Condensation may be performed. As a polymerization method in this case, a suspension polymerization method, a mini-emulsion method, a microemulsion method, an emulsion polymerization method including a multistage swelling method and a seed polymerization, or a resin such as urethane was used as a method for polymerizing particles in an aqueous medium. It is possible to use a heterogeneous polymerization form in a normal aqueous medium such as an extension reaction method. Among these polymerization methods, the microemulsion method and the miniemulsion polymerization method are preferably used, and the miniemulsion polymerization method is most preferable because it is easy to obtain a uniform particle size and uniform particle size distribution.

The temperature during emulsification and dispersion of the crystalline resin monomer in the aqueous medium is preferably 100 ° C. or less, more preferably 60 to 95 ° C., and further preferably 70 to 90 ° C.
The temperature during polycondensation of the crystalline resin monomer in the aqueous medium is preferably 100 ° C. or less, more preferably 50 to 95 ° C., further preferably 60 to 90 ° C., and particularly preferably 65 to 75 ° C. preferable.
When the temperature at the time of emulsification dispersion and polycondensation of the crystalline resin monomer in the aqueous medium is in the above range, a crystalline resin particle dispersion can be obtained with low energy. The fixability is also good, and the polycondensation resin produced during polycondensation does not hydrolyze, which is preferable.

<Outer layer manufacturing process>
The method for producing a resin particle dispersion according to the present invention includes the steps of adding a monomer that forms an amorphous resin to the crystalline resin particle dispersion and performing polycondensation, wherein the inner core is a crystalline resin and the coating layer is an amorphous resin. It is preferable to include a step of obtaining a resin particle dispersion in which resin particles are dispersed (outer layer manufacturing step).
The method of adding the amorphous resin monomer to the crystalline resin particle dispersion is not particularly limited as long as resin particles having an inner core of a crystalline resin and a coating layer of an amorphous resin can be formed by polycondensation. Specifically, for example, a dispersion emulsion in which an amorphous resin monomer is dispersed is prepared and added to the crystalline resin particle dispersion, or crystalline resin particles to which an amorphous resin monomer is added. Examples thereof include a method of emulsifying and dispersing the dispersion by the above-described method for preparing a dispersed emulsion.
When preparing a dispersion of the amorphous resin monomer as the outer layer, a dispersion emulsion in which the monomer is dissolved in an aqueous organic solvent such as ethyl acetate or alcohol may be added.
Among these methods, it is preferable to prepare a dispersion emulsion in which an amorphous resin monomer is dispersed and add it to the crystalline resin particle dispersion.
Preparation of the dispersed emulsion in which the amorphous resin monomer is dispersed can be performed in the same manner as the above-described method for preparing the dispersed emulsion.
The polycondensation reaction of the amorphous resin monomer in the aqueous medium is preferably performed using a polycondensation catalyst. The polycondensation catalyst may be added to the dispersion emulsion in which the amorphous resin monomer is dispersed or may be added to the crystalline resin particle dispersion, and the polycondensation catalyst used in the inner core production process may be added. You can reuse it if you can.
The combination of the crystalline resin and the amorphous resin monomer to be used is a combination in which an outer layer in which the amorphous resin covers part or all of the inner core is formed outside the inner core by polycondensation in an aqueous medium. If it is, there will be no restriction | limiting in particular, It is preferable that the solubility parameter of a crystalline resin and an amorphous resin monomer is a combination which satisfy | fills said Formula (I).

The temperature during emulsification dispersion of the amorphous resin monomer is preferably 100 ° C. or less, more preferably 60 to 95 ° C., and further preferably 70 to 90 ° C.
The temperature during polycondensation of the amorphous resin monomer is preferably 100 ° C. or less, more preferably 60 to 95 ° C., and further preferably 70 to 90 ° C.
When the temperature during emulsification dispersion and polycondensation of the amorphous resin monomer in the outer layer production process is within the above range, a resin particle dispersion having a core / shell structure can be obtained with low energy, and the polycondensation resin In addition, the toner does not hydrolyze, and the toner has favorable chargeability and fixability.

<Polycondensation catalyst>
When polycondensation is performed, polycondensation is caused in an emulsified state in a normal-pressure aqueous medium at 100 ° C. or lower by using a polycondensation catalyst such as a rare earth-containing catalyst or a hydrolase having catalytic activity at a low temperature. This is preferable.
In addition, by using a strong acid having a surface-active effect such as dodecylbenzenesulfonic acid as a polycondensation catalyst, a system having both an emulsifying function and a catalytic function can be used without using a low-temperature active catalyst as described above. This is preferable because polycondensation in a pressurized water medium can be achieved.
Of course, polycondensation can be allowed to proceed in an aqueous medium under pressure of 100 ° C. or higher in order to advance the polymerization more quickly and to use a wider range of monomers.

  Examples of acids having a surface-active effect include alkyl benzene sulfonic acids such as dodecyl benzene sulfonic acid, isopropyl benzene sulfonic acid, and camphor sulfonic acid, alkyl sulfonic acid, alkyl disulfonic acid, alkyl phenol sulfonic acid, alkyl naphthalene sulfonic acid, and alkyl tetralin sulfone. Acids, alkyl allyl sulfonic acids, petroleum sulfonic acids, alkyl benzimidazole sulfonic acids, higher alcohol ether sulfonic acids, alkyl diphenyl sulfonic acids, higher fatty acid sulfates such as monobutyl phenyl phenol sulfate, dibutyl phenyl phenol sulfate, dodecyl sulfate, higher alcohols Sulfate, higher alcohol ether sulfate, higher fatty acid amide alkylol sulfate, higher fatty acid amide alkylated sulfuric acid Steal, naphthenyl alcohol sulfuric acid, sulfated fat, sulfosuccinate, various fatty acids, sulfonated higher fatty acids, higher alkyl phosphates, resin acids, resin acid alcohol sulfuric acid, naphthenic acid, and all these salt compounds are used It is possible to combine a plurality if necessary.

As the rare earth-containing catalyst, scandium (Sc), yttrium (Y), as the lanthanoid element, lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), lutetium (Lu), and the like are effective, especially alkylbenzenesulfone Acid salts, alkyl sulfate esters, or those having a triflate structure are effective.
As the rare earth-containing catalyst, those having a triflate structure such as scandium triflate, yttrium triflate, and lanthanoid triflate are preferable. The lanthanoid triflate is described in detail in Journal of Synthetic Organic Chemistry, Vol. 53, No. 5, p44-54). An example of the triflate is X (OSO ₂ CF ₃ ) _{3 in} the structural formula. Here, X is a rare earth element, and among these, X is more preferably scandium (Sc), yttrium (Y), ytterbium (Yb), samarium (Sm), or the like.

  The hydrolase type catalyst is not particularly limited as long as it catalyzes a polycondensation reaction. Examples of the hydrolase that can be used in the present invention include EC (enzyme numbers) such as carboxyesterase, lipase, phospholipase, acetylesterase, pectinesterase, cholesterol esterase, tannase, monoacylglycerol lipase, lactonase, and lipoprotein lipase. It is classified into EC 3.2 group which acts on glycosyl compounds such as esterase, glucosidase, galactosidase, glucuronidase, xylosidase classified into 3.1 group (see “Enzyme Handbook” (Asakura Shoten, published in 1982) supervised by Maruo and Tamiya). Peptide bonds such as hydrolase, aminopeptidase, chymotrypsin, trypsin, plasmin, subtilisin, etc. classified into EC 3.3 group such as hydrolase and epoxide hydrase Can be mentioned hydrolases classified into EC3.4 group acting, hydrolytic enzymes such as classified into EC3.7 group such as furo retinoic hydrolase.

  Among the above esterases, the enzyme that hydrolyzes glycerol esters and liberates fatty acids is called lipase, but lipase is highly stable in organic solvents, catalyzes ester synthesis reaction in high yield, and is cheaper. There are advantages such as availability. Therefore, also in the manufacturing method of the resin particle dispersion liquid of this invention, it is preferable to use lipase from the surface of a yield or cost.

  Lipases of various origins can be used, but preferred are genus Pseudomonas, genus Alcaligenes, genus Achromobacter, genus Candida, genus Aspergillus, lysopus Examples include lipases obtained from microorganisms such as (Rhizopus) genus and Mucor genus, lipases obtained from plant seeds, lipases obtained from animal tissues, pancreatin, steapsin and the like. Among these, it is preferable to use lipases derived from microorganisms of the genus Pseudomonas, Candida, and Aspergillus.

In the polycondensation catalyst, in order to achieve polycondensation at a lower temperature, a surfactant type catalyst, a rare earth element catalyst, and an enzyme catalyst are effective. As the rare earth metal catalyst, it is particularly preferable to use a catalyst having Y, Sc, Yb, Sm or the like as its constituent components. It should be noted that it is preferable to select a polycondensation catalyst having a higher hydrophobicity or molecular weight in view of the fact that the catalyst is distributed in the emulsion or particles of the polycondensable resin being polymerized and the aqueous medium, It is preferable to select a surfactant type catalyst.
The addition amount of the polycondensation catalyst is preferably 0.1 to 100,000 ppm, more preferably 0.1 to 80,000 ppm based on the polycondensable monomer. .
The polycondensation catalyst can be added to either the aqueous phase or the oil phase, but is preferably added to the aqueous phase. In particular, in the miniemulsion polymerization method, it is preferably added to the aqueous phase.
These polycondensation catalysts may be used alone or in combination.

<Co-surfactant>
The co-surfactant is preferably added in order to reduce Ostwald ripening (Ostwald growth, Ostripping phenomenon) in so-called miniemulsion polymerization.
As the co-surfactant, those known as co-surfactants for the mini-emulsion method can be generally used. For example, alkanes having 8 to 30 carbon atoms such as dodecane, hexadecane, and octadecane, alkyl alcohols having 8 to 30 carbon atoms such as lauryl alcohol, cetyl alcohol, stearyl alcohol, dodecanethiol, lauryl mercaptan, cetyl mercaptan, stearyl mercaptan, etc. C8-C30 alkanethiols, and in addition, acrylic esters and methacrylic esters and their polymers, polymers such as polystyrene and polyester, or polyadducts, carboxylic acids, ketones, amines, etc. However, it is not limited to these.
Among the co-surfactants exemplified above, those preferably used are hexadecane, cetyl alcohol, dodecanethiol, stearyl methacrylate, lauryl methacrylate, polyester, and polystyrene. In particular, for the purpose of avoiding the generation of volatile organic substances, stearyl methacrylate, lauryl methacrylate, polyester, and polystyrene are more preferable.
The polymer and the composition containing a polymer that can be used for the cosurfactant can include, for example, a copolymer with another monomer, a block copolymer, a mixture, and the like. A plurality of co-surfactants can also be used in combination.

(Electrostatic image developing toner and method for producing the same)
The method for producing an electrostatic charge image developing toner (hereinafter also simply referred to as “toner”) of the present invention includes a step of aggregating the resin particles in a dispersion containing at least a resin particle dispersion to obtain aggregated particles (hereinafter referred to as “a toner”). A method for producing an electrostatic charge image developing toner comprising a step of heating and fusing the agglomerated particles (hereinafter also referred to as a “fusing step”), wherein the resin particle dispersion The liquid is the resin particle dispersion of the present invention.
In the method for producing an electrostatic image developing toner of the present invention, the dispersion containing at least the resin particle dispersion of the present invention, if necessary, particles containing colorant particles (the colorant is contained in the resin in the polycondensation step or the like). When added in advance, the particles themselves may be added), release agent particles, other resin particles, or dispersions thereof. The method for producing an electrostatic charge image developing toner according to the present invention comprises agglomerating (associating) toner particles by using a known aggregating method that agglomerates (associates) the resin particles and other added particles in the dispersion. It is possible to adjust the diameter and particle size distribution. Preferably, toner particle adjustment in an emulsion polymerization aggregation method is used. Specifically, the resin particle dispersion of the present invention is mixed with a colorant particle dispersion, a release agent particle dispersion, etc., and an aggregating agent is added to form heteroaggregation to form aggregated particles having a toner diameter. Then, it is obtained by heating to a temperature above the glass transition point or above the melting point of the resin particles to fuse and coalesce the aggregated particles, and wash and dry. In this manufacturing method, the toner shape can be controlled from an indeterminate shape to a spherical shape by selecting a heating temperature condition.

  In the agglomeration step of the present invention, the resin particle dispersion other than the resin particle dispersion of the present invention and the resin particle dispersion of the present invention can be mixed to carry out the steps after the aggregation. At that time, after the resin particle dispersion of the present invention is agglomerated in advance to form the first aggregated particles, the resin particle dispersion of the present invention or another resin particle dispersion is further added to the second shell on the surface of the first particles. It is also possible to make particles multi-layered, such as forming a layer. Of course, it is also possible to produce multilayer particles in the reverse order of the above example.

  As a flocculant, besides a surfactant, an inorganic salt or a divalent or higher metal salt can be suitably used. In particular, when a metal salt is used, it is preferable in characteristics such as aggregation control and toner chargeability. The metal salt compound used for aggregation is obtained by dissolving a general inorganic metal compound or a polymer thereof in a resin particle dispersion, but the metal elements constituting the inorganic metal salt are a periodic table (long period table). 2A, 3A, 4A, 5A, 6A, 7A, 8, 1B, 2B, and 3B, and those having a valence of 2 or more and soluble in the form of ions in the resin particle aggregation system. Good. Specific examples of preferred inorganic metal salts include metal salts such as calcium chloride, calcium nitrate, barium chloride, magnesium chloride, zinc chloride, aluminum chloride, aluminum sulfate, and polyaluminum chloride, polyaluminum hydroxide, calcium polysulfide. And inorganic metal salt polymers. Among these, an aluminum salt and a polymer thereof are particularly preferable. In general, in order to obtain a sharper particle size distribution, it is preferable that the valence of the inorganic metal salt is bivalent rather than monovalent, and trivalent or more valent than bivalent. A type of inorganic metal salt polymer is more suitable.

  In addition to the resin particle dispersion of the present invention, addition polymerization resin particle dispersions prepared using conventionally known emulsion polymerization and the like can be used together. The median diameter of the resin particles in the addition polymerization resin particle dispersion that can be used in the present invention is preferably 0.02 μm or more and 2.0 μm or less as in the resin particle dispersion of the present invention.

  Examples of addition polymerization monomers for preparing these addition polymerization resin particle dispersions include styrenes such as styrene and parachlorostyrene, vinyl naphthalene, vinyl chloride, vinyl bromide, vinyl fluoride, acetic acid. Vinyl esters such as vinyl, vinyl propionate, vinyl benzoate, vinyl butyrate, such as methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, dodecyl acrylate, n-octyl acrylate, acrylic acid 2 -Methylene aliphatic carboxylic acid esters such as chloroethyl, phenyl acrylate, methyl α-chloroacrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, acrylonitrile, methacrylonitrile, acrylamide such as vinyl methyl ether, vinyl ethyl A Monomers having an N-containing polar group, such as N-vinyl compounds such as N-vinylpyrrole, N-vinylcarbazole, N-vinylindole, N-vinylpyrrolidone, etc. Homopolymers and copolymers of vinyl monomers such as vinyl carboxylic acids such as acrylic acid, cinnamic acid and carboxyethyl acrylate, and various waxes can also be used.

  In the case of addition polymerization monomers, emulsion polymerization can be carried out using an ionic surfactant or the like to produce a resin particle dispersion, and in the case of other resins, it is oily and the solubility in water is compared. If it is soluble in a low solvent, the resin is dissolved in those solvents and dispersed in an aqueous medium with a disperser such as a homogenizer together with an ionic surfactant or polymer electrolyte, and then heated or decompressed. Then, the resin particle dispersion can be obtained by evaporating the solvent.

Moreover, a polymerization initiator and a chain transfer agent can also be used at the time of superposition | polymerization of an addition polymerization type monomer.
As the polymerization initiator, a known polymerization initiator can be used. Specifically, for example, ammonium persulfate, potassium persulfate, sodium persulfate, 2,2′-azobis (2-methylpropionamide) dihydro Chloride, t-butylperoxy-2-ethylhexanoate, cumyl perpivalate, t-butylperoxylaurate, benzoyl peroxide, lauroyl peroxide, octanoyl peroxide, di-t-butyl peroxide, t -Butylcumyl peroxide, dicumyl peroxide, 2,2'-azobisisobutyronitrile, 2,2'-azobis (2-methylbutyronitrile), 2,2'-azobis (2,4-dimethyl) Valeronitrile), 2,2′-azobis (4-methoxy-2,4-dimethylvaleronitrile) 1,1-bis (t-butylperoxy) -3,3,5-trimethylcyclohexane, 1,1-bis (t-butylperoxy) cyclohexane, 1,4-bis (t-butylperoxycarbonyl) Cyclohexane, 2,2-bis (t-butylperoxy) octane, n-butyl-4,4-bis (t-butylperoxy) valerate, 2,2-bis (t-butylperoxy) butane, 1, 3-bis (t-butylperoxyisopropyl) benzene, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, 2,5-dimethyl-2,5-di (t-butylperoxy) ) Hexane, 2,5-dimethyl-2,5-di (benzoylperoxy) hexane, di-t-butyldiperoxyisophthalate, 2,2-bis (4,4-di-t-butylperoxide) -Oxycyclohexyl) propane, di-t-butylperoxy α-methylsuccinate, di-t-butylperoxydimethylglutarate, di-t-butylperoxyhexahydroterephthalate, di-t-butylperoxyazelate 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, diethylene glycol-bis (t-butylperoxycarbonate), di-t-butylperoxytrimethyladipate, tris (t-butylperoxy) ) Triazine, vinyltris (t-butylperoxy) silane, 2,2'-azobis (2-methylpropionamidine dihydrochloride), 2,2'-azobis [N- (2-carboxyethyl) -2-methylpropion Amidine], 4,4′-azobis (4-cyanovaleric) De), and the like.
There is no restriction | limiting in particular as a chain transfer agent, Specifically, what has the covalent bond of a carbon atom and a sulfur atom is preferable, For example, thiols are mentioned preferably.

In the present invention, if necessary, known additives can be blended in a combination of one or more kinds within a range that does not affect the results of the present invention. For example, flame retardants, flame retardant aids, brighteners, waterproofing agents, water repellents, magnetic materials, inorganic fillers (surface modifiers), mold release agents, antioxidants, plasticizers, surfactants, dispersants Lubricants, fillers, extender pigments, binders, charge control agents, and the like. These additives can be blended in any production of the coating agent.
In preparing the toner in the present invention, when polycondensation resin particles are polycondensed in an aqueous medium, components necessary for normal toner such as a fixing agent such as a colorant and wax, and other charging assistants are previously added to an aqueous system. It is also possible to mix in advance in a medium and mix with polycondensation resin particles together with polycondensation.

Examples of the colorant that can be used in the present invention include the following.
Examples of the black pigment include carbon black, copper oxide, manganese dioxide, aniline black, activated carbon, nonmagnetic ferrite, and magnetite.
Examples of yellow pigments include yellow lead, zinc yellow, yellow iron oxide, cadmium yellow, chrome yellow, hansa yellow, hansa yellow 10G, benzidine yellow G, benzidine yellow GR, selenium yellow, quinoline yellow, permanent yellow NCG, and the like. be able to.
Examples of the orange pigment include red yellow lead, molybdenum orange, permanent orange GTR, pyrazolone orange, vulcan orange, benzidine orange G, indanthrene brilliant orange RK, and indanthrene brilliant orange GK.
Red pigments include Bengala, Cadmium Red, Red Plum, Mercury Sulfide, Watch Young Red, Permanent Red 4R, Risor Red, Brilliantamine 3B, Brilliantamine 6B, Daypon Oil Red, Pyrazolone Red, Rhodamine B Lake, Lake Red C , Rose Bengal, Eoxin Red, Alizarin Lake and the like.
Blue pigments include bitumen, cobalt blue, alkali blue rake, Victoria blue rake, fast sky blue, induslen blue BC, aniline blue, ultramarine blue, calco oil blue, methylene blue chloride, phthalocyanine blue, phthalocyanine green, malachite green oxare. Rate.
Examples of purple pigments include manganese purple, fast violet B, and methyl violet lake.
Examples of the green pigment include chromium oxide, chromium green, pigment green, malachite green lake, final yellow green G, and the like.
Examples of white pigments include zinc white, titanium oxide, antimony white, and zinc sulfide.
Examples of extender pigments include barite powder, barium carbonate, clay, silica, white carbon, talc, and alumina white.
Examples of the dye include various dyes such as basic, acidic, dispersed, and direct dyes, such as nigrosine, methylene blue, rose bengal, quinoline yellow, and ultramarine blue.

These colorants are used alone or in combination. These colorants can be dispersed by any method, for example, a ball-type mill having a rotating shear type homogenizer, a media mill such as a sand mill or an attritor, a high-pressure counter collision type disperser, or a general dispersion such as a dyno mill. The method can be used to prepare a dispersion of colorant particles.
In addition, these colorants can be dispersed in an aqueous system by a homogenizer using a polar surfactant, and may be added to a mixed solvent together with other fine particle components at once or divided. It may be added in multiple stages.

The colorant of the present invention is selected from the viewpoints of hue angle, saturation, brightness, weather resistance, OHP permeability, and dispersibility in the toner.
The colorant can be added in the range of 4 to 15% by weight with respect to the total weight of the toner constituent solids.
When using a magnetic material as the black colorant, 12 to 240% by weight can be added unlike other colorants.
The blending amount of the colorant is a necessary amount for securing the color developability at the time of fixing. Moreover, OHP transparency and color developability can be ensured by setting the center diameter (median diameter) of the colorant particles in the toner to 100 to 330 nm.
The center diameter of the colorant particles was measured, for example, with a laser diffraction particle size distribution measuring apparatus (LA-920, manufactured by Horiba, Ltd.).

Specific examples of the release agent that can be used in the present invention include, for example, various ester waxes, low molecular weight polyolefins such as polyethylene, polypropylene, and polybutene, silicones that show a softening point by heating, oleic acid amide, and erucic acid amide. , Fatty acid amides such as ricinoleic acid amide and stearic acid amide, plant waxes such as carnauba wax, rice wax, candelilla wax, tree wax and jojoba oil, animal waxes such as beeswax, montan Examples thereof include mineral and petroleum waxes such as wax, ozokerite, ceresin, paraffin wax, microcrystalline wax, microcrystalline wax, Fischer-Tropsch wax, and modified products thereof.
These waxes are hardly dissolved in a solvent such as toluene at room temperature or very little even if dissolved.
These waxes are dispersed in water together with ionic surfactants, polymer electrolytes such as polymer acids and polymer bases, heated above the melting point, and have strong shearing ability and pressure discharge type dispersers (Gorin homogenizer, manufactured by Gorin Co., Ltd.) can be dispersed in the form of particles to prepare a dispersion of particles of 1 μm or less.
It is desirable to add these release agents in the range of 5 to 25% by weight based on the total weight of the toner constituent solids, in order to ensure the peelability of the fixed image in the oilless fixing system.
The particle size of the obtained release agent particle dispersion was measured, for example, with a laser diffraction particle size distribution analyzer (LA-920, manufactured by Horiba, Ltd.). In addition, when using a release agent, after the resin particles, colorant particles, and release agent particles are aggregated, it is possible to add resin particle dispersion to adhere the resin particles to the surface of the aggregated particles. It is desirable from the viewpoint of securing the property.

Specifically, a substance that is magnetized in a magnetic field is used as the magnetic material, but a ferromagnetic powder such as iron, cobalt, or nickel, or a compound such as ferrite or magnetite is used.
When the toner is obtained in the aqueous medium in the present invention, it is necessary to pay attention to the water phase transferability of the magnetic material. preferable.
As the charge control agent, various commonly used charge control agents such as quaternary ammonium salt compounds, nigrosine compounds, dyes composed of complexes of aluminum, iron, chromium, and triphenylmethane pigments can be used. In addition, a material that is difficult to dissolve in water is preferable from the viewpoint of controlling the ionic strength that affects the stability at a time and reducing wastewater contamination.

  Examples of surfactants used for polycondensation, pigment dispersion, resin particle production and dispersion, mold release agent dispersion, aggregation, or stabilization thereof include sulfate ester, sulfonate, phosphate ester, and soap. Anionic surfactants such as amines, cationic surfactants such as amine salt types and quaternary ammonium salt types, and nonionic surfactants such as polyethylene glycols, alkylphenol ethylene oxide adducts, and polyhydric alcohols It is also effective to use them in combination, and general means such as a rotary shear type homogenizer, a ball mill having a media, a sand mill, and a dyno mill can be used for dispersion.

  Examples of flame retardants and flame retardant aids include, but are not limited to, bromine flame retardants that have already been widely used, antimony trioxide, magnesium hydroxide, aluminum hydroxide, and ammonium polyphosphate.

  After completing the coalescence and coalescence process of the aggregated particles, the desired toner particles are obtained through an optional washing process, solid-liquid separation process, and drying process. Replacement cleaning is desirable. Moreover, although there is no restriction | limiting in particular in a solid-liquid separation process, From the point of productivity, suction filtration, pressure filtration, etc. are suitable. Further, the drying process is not particularly limited, but freeze drying, flash jet drying, fluidized drying, vibration fluidized drying and the like are preferably used from the viewpoint of productivity.

In the toner using the resin particle dispersion of the present invention, the softening point thereof is determined mainly by the melting point of the crystalline resin. Therefore, the toner having the lowest fixing temperature can be obtained by using the crystalline resin having a low melting point. In addition, since the non-crystalline resin produces a large viscoelasticity when melted, as a result, a toner having a low temperature fixability and excellent offset resistance can be obtained.
In this case, the polycondensation resin may take any form such as an amorphous resin, a crystalline resin, or a mixed form thereof. In particular, when aiming at a low-temperature fixing toner, the crystalline melting point is 40 ° C. or more. It is preferable to include at least a crystalline resin showing a range of 150 ° C. or lower. When the crystal melting point is 40 ° C. or higher, the obtained toner has excellent fluidity, developability, filming resistance, offset resistance and durability, and when the crystal melting point is 150 ° C., sufficient melting is achieved. Is obtained, the minimum fixing temperature does not increase, and the fixing property is good.

Furthermore, the toner of the present invention is preferably used by mixing inorganic particles or adding them to the resin particle surface for the purpose of imparting fluidity or improving cleaning properties.
The inorganic particles that can be used in the present invention are particles having a primary particle diameter of 5 nm to 2 μm, preferably 5 nm to 500 nm. Moreover, it is preferable that the specific surface area by BET method is 20-500 m < ² > / g. The proportion mixed with the toner is 0.01 to 5% by weight, preferably 0.01 to 2.0% by weight.
Examples of such inorganic particles include silica powder, alumina, titanium oxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate, zinc oxide, silica sand, clay, mica, wollastonite, diatomaceous earth, Examples thereof include chromium oxide, cerium oxide, bengara, antimony trioxide, magnesium oxide, zirconium oxide, barium sulfate, barium carbonate, calcium carbonate, silicon carbide, and silicon nitride, and silica powder is particularly preferable.
The silica powder here is a powder having a Si—O—Si bond, and includes both those produced by a dry method and a wet method. In addition to anhydrous silicon dioxide, any of aluminum silicate, sodium silicate, potassium silicate, magnesium silicate, zinc silicate and the like may be used, but those containing SiO _{2 in an amount} of 85% by weight or more are preferable.
Specific examples of these silica powders include various commercially available silicas, but those having a hydrophobic group on the surface are preferable. For example, AEROSIL R-972, R-974, R-805, R-812 (manufactured by Aerosil Co., Ltd.) ), Thalax 500 (manufactured by Tarco) and the like. In addition, silica powder treated with a silane coupling agent, a titanium coupling agent, silicon oil, silicon oil having an amine in the side chain, or the like can be used.

The cumulative volume average particle diameter D ₅₀ of the toner of the present invention is suitably in the range of 3.0 to 9.0 μm, preferably in the range of 3.0 to 5.0 μm. It is preferable that D ₅₀ is 3.0 μm or more because the adhesive force is appropriate and the developability is excellent. Further, when D ₅₀ is less than 9.0 .mu.m, preferably for the resolution of the image is good.
The volume average particle size distribution index GSDv of the toner of the present invention is preferably 1.30 or less. A GSDv of 1.30 or less is preferable because the resolution is good and image defects such as toner scattering and fogging hardly occur.
The cumulative volume average particle diameter D ₅₀ and the average particle size distribution index of the toner of the present invention are measured by a measuring instrument such as Coulter Counter TAII (manufactured by Beckman Coulter, Inc.), Multisizer II (manufactured by Beckman Coulter, Inc.), or the like. For the particle size range (channel) divided based on the particle size distribution, draw the cumulative distribution from the small diameter side for the volume and number, respectively, and the particle size to be 16% is the volume D _16v , number D _16P , 50% cumulative _{Are defined} as a volume D _50v and a number D _50P , and a particle diameter at a cumulative 84% is defined as a volume D _84v and a number D _84P . Using these, the volume average particle size distribution index (GSDv) is calculated as (D _84v / D _16V ) ^1/2 and the number average particle size distribution index (GSDp) is calculated as (D _84P / D _16P ) ^1/2 .

  The shape factor SF1 of the toner of the present invention is preferably in the range of 100 to 140, more preferably in the range of 110 to 135, from the viewpoint of image formability. The shape factor SF1 of the present invention can be quantified mainly by analyzing a microscope image or a scanning electron microscope image with an image analyzer, and is obtained by the following method, for example. First, an optical microscope image of the toner spread on the slide glass is taken into a Luzex image analyzer through a video camera, and the absolute maximum length of toner particles and the projected area of toner particles are measured for 50 or more toners. It can obtain | require by the type | formula of.

式中、ＭＬ：トナー粒子の絶対最大長、Ａ：トナー粒子の投影面積と定義する。

In the formula, ML is defined as an absolute maximum length of toner particles, and A is defined as a projected area of toner particles.

(Electrostatic image developer)
The electrostatic image developing toner of the present invention can be used as an electrostatic image developer. The developer is not particularly limited except that it contains the electrostatic image developing toner, and can have an appropriate component composition depending on the purpose. When the electrostatic image developing toner is used alone, it is prepared as a one-component electrostatic image developer, and when used in combination with a carrier, it is prepared as a two-component electrostatic image developer.
As a one-component developer, a method in which a charged toner is formed by frictional charging with a developing sleeve or a charging member, and development according to an electrostatic latent image can be applied.
The carrier is not particularly limited, but usually, magnetic particles such as iron powder, ferrite, iron oxide powder, nickel, etc .; the magnetic particles as a core material and the surface thereof as a styrene resin, vinyl resin, ethylene resin, rosin Resin-coated carrier formed by coating a resin such as a resin based on polyester, polyester or melamine, or a wax such as stearic acid, and forming a resin coating layer; a magnetic material obtained by dispersing magnetic particles in a binder resin Examples include a distributed carrier. Among them, the resin-coated carrier is particularly preferable because the chargeability of the toner and the resistance of the entire carrier can be controlled by the configuration of the resin coating layer.
The mixing ratio of the toner of the present invention and the carrier in the two-component electrostatic image developer is usually 2 to 10 parts by weight of the toner with respect to 100 parts by weight of the carrier. Moreover, the preparation method of a developing agent is not specifically limited, For example, the method of mixing with a V blender etc. is mentioned.

(Image forming method)
Further, the electrostatic image developing toner and the electrostatic image developer of the present invention can be used in an ordinary electrostatic image developing system (electrophotographic system) image forming method.
The image forming method of the present invention includes a latent image forming step of forming an electrostatic latent image on the surface of the latent image holding member, and developing the electrostatic latent image formed on the surface of the latent image holding member with a developer containing toner. A developing step for forming a toner image, a transfer step for transferring the toner image formed on the surface of the latent image holding member to the surface of the transfer target, and a fixing for thermally fixing the toner image transferred to the surface of the transfer target. An electrostatic charge image developing toner of the present invention as the toner, or an electrostatic charge image developer of the present invention as the developer.
For each of the above steps, a known step can be used in the image forming method, and are described in, for example, JP-A-56-40868 and JP-A-49-91231. Further, the image forming method of the present invention may include steps other than the above-described steps. For example, a cleaning step for removing the electrostatic charge image developer remaining on the electrostatic latent image carrier is preferable. Can be mentioned. In the image forming method of the present invention, an embodiment that further includes a recycling step is preferable. The recycling step is a step of transferring the electrostatic charge image developing toner collected in the cleaning step to a developer layer. The image forming method including the recycling step can be performed using an image forming apparatus such as a toner recycling system type copying machine or facsimile machine. The present invention can also be applied to a recycling system in which the cleaning process is omitted and toner is collected simultaneously with development.

As the latent image holding member, for example, an electrophotographic photosensitive member and a dielectric recording member can be used.
In the case of an electrophotographic photosensitive member, the surface of the electrophotographic photosensitive member is uniformly charged by a corotron charger, a contact charger or the like and then exposed to form an electrostatic latent image (latent image forming step). Next, the toner particles are attached to the electrostatic latent image by contacting or approaching a developing roll having a developer layer formed on the surface, thereby forming a toner image on the electrophotographic photosensitive member (developing step). The formed toner image is transferred onto the surface of a transfer medium such as paper using a corotron charger or the like (transfer process). Further, the toner image transferred onto the surface of the transfer medium is thermally fixed by a fixing device (fixing step), and a final toner image is formed.
In the heat fixing by the fixing device, a release agent is usually supplied to a fixing member in the fixing device in order to prevent offset and the like.

EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited at all.
The toner of the present example was prepared by preparing the following resin particle dispersion, colorant particle dispersion, and release agent particle dispersion, respectively, and mixing and stirring them at a predetermined ratio, while polymerizing a metal salt. And are ionically neutralized to form agglomerated particles. Next, an inorganic hydroxide is added to adjust the pH in the system from weakly acidic to neutral, and then the mixture is heated to a temperature equal to or higher than the glass transition point of the resin particles to fuse and unite. After completion of the reaction, a desired toner is obtained through sufficient washing, solid-liquid separation, and drying processes. Hereinafter, each preparation method is demonstrated.

(Preparation of monomer dispersion emulsion (1))
<Production of aqueous phase>
1.66 parts by weight of dodecylbenzenesulfonic acid 200 parts by weight of ion-exchanged water is mixed and dissolved.
<Production of oil phase>
1,9-nonanediol 10.26 parts by weight Dodecanedioic acid (1,10-decanedicarboxylic acid) 14.74 parts by weight are mixed and heated to 120 ° C. to melt.
The oil phase monomer mixed solution is put into the aqueous phase dodecylbenzenesulfonic acid aqueous solution and emulsified at 10,000 rpm for 3 minutes using a homogenizer (manufactured by IKA, Ultra Tarrax). 1) was obtained.

(Preparation of monomer dispersion emulsion (2))
<Production of aqueous phase>
1.66 parts by weight of dodecylbenzenesulfonic acid 200 parts by weight of ion-exchanged water is mixed and dissolved.
<Production of oil phase>
12.12 parts by weight of 1,12-dodecanediol 12.52 parts by weight of sebacic acid are mixed and heated to 120 ° C. to melt.
The oil phase monomer mixed solution is put into the aqueous phase dodecylbenzenesulfonic acid aqueous solution and emulsified at 10,000 rpm for 3 minutes using a homogenizer (manufactured by IKA, Ultra Tarrax). 2) was obtained.

(Preparation of monomer dispersion emulsion (3))
<Production of aqueous phase>
1.66 parts by weight of dodecylbenzenesulfonic acid 200 parts by weight of ion-exchanged water is mixed and dissolved.
<Production of oil phase>
8.51 parts by weight of 1,6-hexanediol 16.49 parts by weight of dodecanedioic acid are mixed and heated to 120 ° C. to melt.
The oil phase monomer mixed solution is poured into the aqueous phase dodecylbenzenesulfonic acid aqueous solution, and emulsified at 10,000 rpm for 3 minutes using a homogenizer (IKA Corporation, Ultra Tarrax). 3) was obtained.

(Preparation of monomer dispersion emulsion (4))
<Production of aqueous phase>
1.66 parts by weight of dodecylbenzenesulfonic acid 200 parts by weight of ion-exchanged water is mixed and dissolved.
<Production of oil phase>
Propylene glycol 9.14 parts by weight Glutaric acid 15.86 parts by weight are mixed and heated to 120 ° C. to melt.
The oil phase monomer mixed solution is put into the aqueous phase dodecylbenzenesulfonic acid aqueous solution and emulsified at 10,000 rpm for 3 minutes using a homogenizer (manufactured by IKA, Ultra Tarrax). 4) was obtained.

(Preparation of monomer dispersion emulsion (5))
<Production of aqueous phase>
1.66 parts by weight of dodecylbenzenesulfonic acid 200 parts by weight of ion-exchanged water is mixed and dissolved.
<Production of oil phase>
Ethylene glycol 7.9 parts by weight Glutaric acid 17.01 parts by weight is mixed and heated to 120 ° C. to melt.
The oil phase monomer mixed solution is put into the aqueous phase dodecylbenzenesulfonic acid aqueous solution and emulsified at 10,000 rpm for 3 minutes using a homogenizer (manufactured by IKA, Ultra Tarrax). 5) was obtained.

(Preparation of monomer dispersion emulsion (6))
<Production of aqueous phase>
1.66 parts by weight of dodecylbenzenesulfonic acid 200 parts by weight of ion-exchanged water is mixed and dissolved.
<Production of oil phase>
Butanediol 9.54 parts by weight Adipic acid 15.46 parts by weight is mixed and heated to 120 ° C. to melt.
The oil phase monomer mixed solution is put into the aqueous phase dodecylbenzenesulfonic acid aqueous solution and emulsified at 10,000 rpm for 3 minutes using a homogenizer (manufactured by IKA, Ultra Tarrax). 6) was obtained.

(Preparation of monomer dispersion emulsion (7))
<Production of aqueous phase>
1.66 parts by weight of dodecylbenzenesulfonic acid 200 parts by weight of ion-exchanged water is mixed and dissolved.
<Production of oil phase>
Bisphenol A-ethylene oxide 2 mol adduct 17.53 parts by weight 1,4-cyclohexanedicarboxylic acid 7.47 parts by weight are mixed, heated to 120 ° C. and melted.
The oil phase monomer mixed solution is poured into the aqueous phase dodecylbenzenesulfonic acid aqueous solution, and emulsified at 10,000 rpm for 3 minutes using a homogenizer (IKA Corporation, Ultra Tarrax). 7) was obtained.

(Preparation of monomer dispersion emulsion (8))
<Production of aqueous phase>
1.66 parts by weight of dodecylbenzenesulfonic acid 200 parts by weight of ion-exchanged water is mixed and dissolved.
<Production of oil phase>
Bisphenol A-ethylene oxide 2 mol adduct 16.13 parts by weight Dimethyl terephthalate 8.87 parts by weight are mixed, heated to 120 ° C. and melted.
The oil phase monomer mixed solution is put into the aqueous phase dodecylbenzenesulfonic acid aqueous solution and emulsified at 10,000 rpm for 3 minutes using a homogenizer (manufactured by IKA, Ultra Tarrax). 8) was obtained.

(Preparation of monomer-dispersed emulsion (9))
<Production of aqueous phase>
1.66 parts by weight of dodecylbenzenesulfonic acid 200 parts by weight of ion-exchanged water is mixed and dissolved.
<Production of oil phase>
Bisphenol A-ethylene oxide 2 mol adduct 15.98 parts by weight 1,4-phenylenediacetic acid 9.02 parts by weight are mixed and heated to 120 ° C. to melt.
The oil phase monomer mixed solution is put into the aqueous phase dodecylbenzenesulfonic acid aqueous solution and emulsified at 10,000 rpm for 3 minutes using a homogenizer (manufactured by IKA, Ultra Tarrax). 9) was obtained.

(Preparation of monomer dispersion emulsion (10))
<Production of aqueous phase>
1.66 parts by weight of dodecylbenzenesulfonic acid 200 parts by weight of ion-exchanged water is mixed and dissolved.
<Production of oil phase>
Bisphenol A (without adduct) 14.47 parts by weight 10.53 parts by weight of terephthalic acid are mixed and heated to 120 ° C. to melt.
The oil phase monomer mixed solution is put into the aqueous phase dodecylbenzenesulfonic acid aqueous solution and emulsified at 10,000 rpm for 3 minutes using a homogenizer (manufactured by IKA, Ultra Tarrax). 10) was obtained.

(Preparation of monomer dispersion emulsion (11): dispersion emulsion of vinyl resin monomer)
<Production of aqueous phase>
1.66 parts by weight of dodecylbenzenesulfonic acid 200 parts by weight of ion-exchanged water is mixed and dissolved.
<Production of oil phase>
Styrene 18.00 parts by weight n-butyl acrylate 7.00 parts by weight Stearyl methacrylate 1.66 parts by weight Dodecanethiol 0.07 parts by weight is mixed and heated to 120 ° C. to melt.
The oil phase monomer mixed solution is put into the aqueous phase dodecylbenzenesulfonic acid aqueous solution and emulsified at 10,000 rpm for 3 minutes using a homogenizer (manufactured by IKA, Ultra Tarrax). 11) was obtained.

(Preparation of resin particle dispersion (1))
The monomer-dispersed emulsion (1), which is an emulsion, was charged into a reactor equipped with a stirrer, and maintained at 70 ° C. for 24 hours for polycondensation. A small amount of this reaction product was taken out and subjected to NMR analysis, and it was confirmed that polyester was synthesized by polycondensation at this point.
NMR measurement was performed by using deuterium chloroform and measuring proton NMR (300 MHz manufactured by Varian). In addition, the identification of polyester in the measurement of NMR is based on the description of p.2836 of M. Barrere, K. Landfester, Polymer, 44, p.2833-2841 (2003). The polyester peaks were confirmed by comparing the area strengths of the two, and the progress of polycondensation was judged.
By the above method, a resin particle dispersion liquid (1) having a center diameter of dispersed resin particles of 220 nm, a weight average molecular weight of 8,580, and a melting point of 69.2 ° C. was obtained.

(Preparation of resin particle dispersion (2))
Except having changed into the monomer dispersion | distribution emulsion (2), it produced by the method similar to the resin particle dispersion (1). As a result, a resin particle dispersion (2) was obtained in which the center diameter of the dispersed resin particles was 290 nm, the weight average molecular weight of the polyester was 8,950, and the melting point of the polyester was 70.3 ° C.

(Preparation of resin particle dispersion (3))
Except having changed to the monomer dispersion | distribution emulsion (3), it produced by the method similar to the resin particle dispersion (1). As a result, a resin particle dispersion (3) in which the center diameter of the dispersed resin particles was 280 nm, the weight average molecular weight of polyester was 7,450, and the melting point of polyester was 67.2 ° C. was obtained.

(Preparation of resin particle dispersion (4))
Except having changed to the monomer dispersion | distribution emulsion (4), it produced by the method similar to the resin particle dispersion (1). As a result, a resin particle dispersion (4) in which the center diameter of the dispersed resin particles was 420 nm, the weight average molecular weight of the polyester was 4,100, and the melting point of the polyester was 66.5 ° C. was obtained.

(Preparation of resin particle dispersion (5))
Except having changed into the monomer dispersion | distribution emulsion (5), it produced by the method similar to the resin particle dispersion (1). As a result, a resin particle dispersion (5) having a dispersed resin particle center diameter of 440 nm, a polyester weight average molecular weight of 4,350, and a polyester melting point of 66.1 ° C. was obtained.

(Preparation of resin particle dispersion (6))
Except having changed to the monomer dispersion | distribution emulsion (6), it produced by the method similar to the resin particle dispersion (1). As a result, a resin particle dispersion (6) having a dispersed resin particle center diameter of 400 nm, a polyester weight average molecular weight of 4,690, and a polyester melting point of 67.1 ° C. was obtained.

(Preparation of resin particle dispersion (7))
To 140 parts by weight of the resin particle dispersion (1), 140 parts by weight of the monomer-dispersed emulsion (7) maintained at 70 ° C. is added and charged into a reactor equipped with a stirrer and maintained at 70 ° C. while stirring. Furthermore, polycondensation was carried out by maintaining for 24 hours. As a result, a resin particle dispersion (7) having a center diameter of dispersed resin particles of 290 nm was obtained.
In order to investigate the characteristics of the amorphous polyester, only the monomer-dispersed emulsion (7) was maintained at 70 ° C., charged into a reactor equipped with a stirrer, and held for 24 hours while stirring to perform polycondensation. As a result of measuring the molecular weight and the glass transition point, the weight average molecular weight of the polyester was 5,790, and the glass transition point (Tg) of the polyester was 53.5 ° C.

<Evaluation of resin particle structure>
Here, as a technique for analyzing the core / shell structure (double-layer structure) in the composite resin particles of crystalline polyester / non-crystalline polyester, a cross-sectional TEM (transmission type) using an osmium oxide staining method or the like is basically used. (Electron microscope) (JEOL 1010). In the TEM photograph obtained by the observation, a difference occurs in contrast between the crystalline polyester phase and the amorphous polyester phase, so that each phase can be identified.
As a result of structural analysis by the dyeing method TEM of the resin dispersion obtained using this method, it has a two-layer structure in which the crystalline polyester is the core (inner core) and the amorphous polyester is the shell (outer layer). Was confirmed.
Further, for the 10 particles present in the obtained TEM photographic image, the average outer layer thickness obtained by converting the thickness of the outer layer (shell) at five locations for each particle to a scale was 0.045 μm.

(Preparation of resin particle dispersion (8))
140 parts by weight of monomer dispersion emulsion (8) maintained at 70 ° C. is added to 140 parts by weight of the resin particle dispersion (2), and the mixture is charged into a reactor equipped with a stirrer and maintained at 70 ° C. while stirring. Further, the polycondensation was carried out for 24 hours.
As a result, a resin particle dispersion (8) having a central diameter of dispersed resin particles of 360 nm was obtained.
In order to investigate the characteristics of the amorphous polyester, only the monomer-dispersed emulsion (8) was maintained at 70 ° C., charged into a reactor equipped with a stirrer, and held for 24 hours while stirring to perform polycondensation. As a result of measuring the molecular weight and the glass transition point, the weight average molecular weight of the polyester was 5,240, and the glass transition point (Tg) of the polyester was 54.5 ° C.
Furthermore, as a result of structural analysis of the resin particles obtained here with a TEM photograph, it was confirmed that the crystalline polyester had a two-layer structure in which the core and the amorphous polyester were the shell.
Further, for the 10 particles present in the obtained TEM photographic image, the average outer layer thickness obtained by converting the outer layer (shell) thickness at five locations per particle into a scale was 0.039 μm.

(Preparation of resin particle dispersion (9))
140 parts by weight of the monomer dispersion emulsion (9) maintained at 70 ° C. is added to 140 parts by weight of the resin particle dispersion (3), and the mixture is charged into a reactor equipped with a stirrer and maintained at 70 ° C. while stirring. Further, the polycondensation was carried out for 24 hours.
As a result, a resin particle dispersion (9) having a center diameter of dispersed resin particles of 350 nm was obtained.
In order to investigate the characteristics of the amorphous polyester, only the monomer-dispersed emulsion (9) was maintained at 70 ° C., charged into a reactor equipped with a stirrer, and maintained for 24 hours while stirring to perform polycondensation. As a result of measuring the molecular weight and glass transition point, the weight average molecular weight of the polyester was 5,540 and the glass transition point (Tg) of the polyester was 54.0 ° C.
Furthermore, as a result of structural analysis of the resin particles obtained here with a TEM photograph, it was confirmed that the crystalline polyester had a two-layer structure in which the core and the amorphous polyester were the shell.
Further, for the 10 particles present in the obtained TEM photographic image, the average outer layer thickness obtained by converting the outer layer (shell) thickness at five locations for each particle to a scale was 0.049 μm.

(Preparation of resin particle dispersion (10))
140 parts by weight of the monomer dispersion emulsion (10) maintained at 70 ° C. is added to 140 parts by weight of the resin particle dispersion (4), charged into a reactor equipped with a stirrer, and maintained for 24 hours while stirring. Polycondensation was performed.
As a result, a resin particle dispersion (10) having a central diameter of dispersed resin particles of 440 nm was obtained.
In order to investigate the characteristics of the amorphous polyester, only the monomer-dispersed emulsion (10) was maintained at 70 ° C., charged into a reactor equipped with a stirrer, and held for 24 hours while stirring to perform polycondensation. As a result of measuring the molecular weight and the glass transition point, the polyester had a weight average molecular weight of 3,150 and the polyester had a glass transition point (Tg) of 50.8 ° C.
As a result of structural analysis of the resin particles obtained here with a TEM photograph, it was confirmed that the amorphous polyester was intermittently attached to the outside of the spherical crystalline polyester particles. It was confirmed that the crystalline polyester did not completely cover the crystalline polyester core, and the presence of particles consisting only of the amorphous polyester.

(Preparation of resin particle dispersion (11))
To 270 parts by weight of the resin particle dispersion (5), 10 parts by weight of the monomer-dispersed emulsion (10) maintained at 70 ° C. is added, put into a reactor equipped with a stirrer, and maintained for 24 hours while stirring. Polycondensation was performed.
As a result, a resin particle dispersion (11) having a central diameter of dispersed resin particles of 440 nm was obtained.
As a result of structural analysis of the resin particles obtained here with a TEM photograph, it was confirmed that the amorphous polyester was intermittently attached to the outside of the spherical crystalline polyester particles. It was confirmed that the crystalline polyester did not completely cover the crystalline polyester core, and the presence of particles consisting only of the amorphous polyester.

(Preparation of resin particle dispersion (12))
140 parts by weight of the monomer dispersion emulsion (11) maintained at 70 ° C. is added to 140 parts by weight of the resin particle dispersion (6), and the mixture is put into a reactor equipped with a stirrer and stirred for 5 minutes. A solution prepared by dissolving 8 parts by weight of ammonium persulfate in 10 parts by weight of ion-exchanged water was dropped, and radical polymerization was performed for 6 hours while maintaining the temperature at 70 ° C. in a nitrogen atmosphere.
As a result, a resin particle dispersion (11) having a center diameter of dispersed resin particles of 450 nm was obtained.
In order to investigate the characteristics of the amorphous vinyl-based resin, a solution containing only the monomer-dispersed emulsion (11) was maintained at 70 ° C. and then charged into a reactor equipped with a stirrer and stirred for 5 minutes. A solution obtained by dissolving 8 parts by weight of ammonium persulfate in 10 parts by weight of ion-exchanged water was dropped, and radical polymerization was performed for 6 hours while maintaining the temperature at 70 ° C. in a nitrogen atmosphere. Was 30,900 and the glass transition point (Tg) was 54.8 ° C.
Furthermore, as a result of structural analysis of the resin particles obtained here with a TEM photograph, it was confirmed that the crystalline polyester had a two-layer structure in which the core and the amorphous vinyl resin were the shell.
Further, for the 10 particles present in the obtained TEM photographic image, the average outer layer thickness obtained by converting the thickness of the outer layer (shell) at five locations per particle into a scale was 0.032 μm.

(Preparation of colorant particle dispersion (1))
Yellow pigment (manufactured by Dainichi Seika Co., Ltd., CI Pigment Yellow 74) 50 parts by weight Anionic surfactant (Daiichi Kogyo Seiyaku, Neogen R) 5 parts by weight Ion-exchanged water 200 parts by weight The above components are mixed and dissolved. A yellow colorant particle dispersion (1) having a center diameter of 240 nm and a solid content of 21.5% was obtained by dispersing for 5 minutes with a homogenizer (manufactured by IKA, Ultra Tarrax) and for 10 minutes with an ultrasonic bath.

(Preparation of colorant particle dispersion (2))
In the preparation of the colorant particle dispersion (1), a colorant particle dispersion (1) was used except that a cyan pigment (manufactured by Dainichi Seika Co., Ltd., copper phthalocyanine CI Pigment Blue 15: 3) was used instead of the yellow pigment. The Cyan colorant particle dispersion liquid (2) having a center diameter of 190 nm and a solid content of 21.5% was prepared in the same manner as above.

(Preparation of colorant particle dispersion (3))
In the preparation of the colorant particle dispersion (1), the same procedure as in the colorant particle dispersion (1) except that a magenta pigment (manufactured by Dainichi Ink Chemical Co., Ltd., CI Pigment Red122) was used instead of the yellow pigment To obtain a Magenta colorant particle dispersion (3) having a center diameter of 165 nm and a solid content of 21.5%.

(Preparation of colorant particle dispersion (4))
The colorant particle dispersion (1) was prepared in the same manner as the colorant particle dispersion (1) except that a black pigment (Cabot, carbon black) was used instead of the yellow pigment, and the center diameter was 170 nm. A black colorant particle dispersion (4) having a solid content of 21.5% was obtained.

(Preparation of release agent particle dispersion)
Paraffin wax (manufactured by Nippon Seiwa Co., Ltd., HNP9; melting point 70 ° C.) 50 parts by weight Anionic surfactant (Dow Fax manufactured by Dow Chemical Co., Ltd.) 5 parts by weight Ion-exchanged water 200 parts by weight After sufficiently dispersing with a homogenizer (IKA, Ultra Tarrax T50), it is dispersed with a pressure discharge type homogenizer (Gorin homogenizer, Gorin), release agent particles having a center diameter of 180 nm and a solid content of 21.5%. A dispersion was obtained.

[Toner Example 1]
(Preparation of toner particles)
Resin particle dispersion (7) 140 parts by weight Colorant particle dispersion (1) 40 parts by weight (8.6 parts by weight of pigment)
40 parts by weight of release agent particle dispersion (8.6 parts by weight of release agent)
Polyaluminum chloride 0.15 parts by weight Deionized water 300 parts by weight The above components were thoroughly mixed and dispersed in a round stainless steel flask using a homogenizer (IKA, Ultra Turrax T50), and then heated in an oil bath for heating. The mixture was heated to 42 ° C. with stirring and maintained at 42 ° C. for 60 minutes, and then the pH in the system was adjusted to 6.0 with a 0.5 mol / liter sodium hydroxide aqueous solution. Heated to ° C. During the temperature rise to 95 ° C, the pH in the system usually drops to 5.0 or less, but here, an aqueous sodium hydroxide solution is added dropwise to keep the pH from dropping to 5.5 or less. did.
After completion of the reaction, the mixture was cooled, filtered, sufficiently washed with ion exchange water, and then solid-liquid separated by Nutsche suction filtration. Then, it was redispersed in 3 liters of ion exchange water at 40 ° C., and stirred and washed at 300 rpm for 15 minutes. This washing operation was repeated 5 times, followed by solid-liquid separation by Nutsche suction filtration, and then vacuum drying for 12 hours to obtain toner particles.

When the particle size of the toner particles was measured with a Coulter counter, the cumulative volume average particle size D ₅₀ was 4.28 μm, and the volume average particle size distribution index GSDv was 1.20. The shape factor SF1 of the toner particles obtained from the shape observation by Luzex was 131 potato shapes.
To 50 parts by weight of the above toner particles, 1.4 parts by weight of hydrophobic silica (manufactured by Cabot, Ts720) was added and mixed by a sample mill to obtain an externally added toner.
Then, using a ferrite carrier having an average particle diameter of 50 μm coated with 1% polymethyl methacrylate (manufactured by Soken Chemical Co., Ltd.), the externally added toner was weighed so that the toner concentration would be 8%. A developer was prepared by stirring and mixing for a minute.

(Evaluation of toner)
(1) <Fixing evaluation>
For fixing and image quality evaluation with the developer obtained by the method described above, image formation was performed using a Docu Center Color 500CP remodeling machine manufactured by Fuji Xerox Co., Ltd., and image quality evaluation of fixing temperature and initial image quality was performed. In this case, as the evaluation items, the minimum fixing temperature is the minimum temperature of the heating roller in which the toner particles form a continuous film layer, the hot offset generation temperature is the minimum temperature at which the hot offset phenomenon occurs, and the image quality characteristics are visually inspected for unevenness in image quality. Judged.

[1] Determination of minimum fixing temperature by cloth rubbing method After creating an unfixed image with the above-mentioned copying machine, a heat roller having a surface layer made of Teflon (registered trademark) with a diameter of 30 mm and a surface layer formed of silicone rubber. Fixing the toner image with the sample toner transferred onto the transfer paper of 64 g / m ² at a linear velocity of 70 mm / second, a linear pressure of 0.8 kg / cm, and a nip width of 4.9 mm by a fixing device comprising a pressure roller. The temperature of the heat roller is increased stepwise by 5 ° C. within the range of 80 to 240 ° C., and repeated at each temperature, and the formed fixed image is subjected to Kim wipe rubbing and sufficient rubbing resistance The minimum fixing temperature was set as the minimum fixing temperature for a fixed image showing The fixing device used here does not have a silicone oil supply mechanism. The evaluation standard of the minimum fixing temperature by the cloth rubbing method is
The temperature at which image distortion disappears for the first time by the cloth rubbing method is 120 ° C. or lower.
When the temperature at which image distortion disappears for the first time by the cloth rubbing method is higher than 120 ° C.
It was.

[2] Determination of Minimum Fixing Temperature by Measuring Image Glossiness For an image sample that has been fixed by the above fixing method, using a GM26D manufactured by Murakami Color Research Laboratory, the incident light angle to the image sample is 75 degrees. As a result of measuring the glossiness, the temperature at which the glossiness was 40 or more was determined as the minimum fixing temperature by the image glossiness measurement. The evaluation standard of the minimum fixing temperature by image gloss measurement is
Glossiness exceeds 40 for the first time 120 ° C or less ...
When the temperature where the glossiness exceeds 40 for the first time is higher than 120 ° C ...
It was.

[3] Hot offset generation temperature The offset generation temperature is measured by creating an unfixed image with the copying machine, transferring the toner image and performing fixing processing with the above-described fixing device, and then applying a blank transfer paper in the same manner. The operation in which the set temperature of the heat roller of the fixing unit is sequentially increased every 5 ° C. from 180 ° C. to 230 ° C. in the operation of sending the toner to the fixing unit under the conditions of The offset generation temperature was determined by using the lowest set temperature at which the toner was smeared. Evaluation criteria are
Offset generation temperature 220 ° C or higher or not generated
Offset generation temperature 200 ℃ ~ 215 ℃ ・ ・ ・ ・ ・ ・ △
Offset generation temperature 195 ° C or lower
It was.

[4] Image quality The image quality was determined as follows by measuring the fine line reproducibility of the image with the fine line fixed and the fog (visually) of the non-fixed part with a loupe.
There is no unevenness in the fine lines and there is no fogging.
The image quality is slightly uneven ...
The image quality is uneven ... X

[5] Image Glossiness The image glossiness of the image sample fixed at 140 ° C. by the above fixing method using the GM26D manufactured by Murakami Color Research Laboratory under the condition that the incident light angle to the image sample is 75 degrees. Was measured.

As a result of fixing evaluation by the above method,
The minimum fixing temperature according to the rubbing resistance evaluation is 95 ° C.,
The minimum fixing temperature by image glossiness measurement was as good as 100 ° C.
Further, the occurrence temperature of hot offset was as good as 220 ° C., and the image quality was also good without any unevenness or fog.
In this embodiment, the image glossiness when fixing at 140 ° C. was as good as 66%.

(2) <Mechanical strength evaluation>
A device capable of driving the developing machine of the Fuji Xerox full color copying machine Docu Center Color 500 alone was manufactured, and the developer was put into the developing machine and driven under the same conditions as in the copying machine. Therefore, the developer in the developing machine was sampled at an arbitrary time, and the particle size distribution of the toner was measured. The driving time was plotted on the X axis, and the cumulative value of 3.0 μm or less in the number average distribution was plotted on the Y axis, the slope was defined as the mechanical strength index, and the mechanical strength was evaluated based on the numerical value. The larger this value is, the easier it is to crush in the developing machine and the lower the mechanical strength.
Mechanical strength index is 0.20 or less ...
Mechanical strength index is 0.21 ~ 0.40 ・ ・ ・ ・ △
Mechanical strength index is 0.40 or more ...
It was.
Therefore, the developer was introduced into the developing machine and evaluated. As a result, the mechanical strength index was as good as 0.16.

(3) <Evaluation of triboelectric charge>
1.5 parts by weight of the obtained toner and 30 parts by weight of a carrier (a carrier for Docu Center Color 500 manufactured by Fuji Xerox) were left in a high temperature and high humidity (temperature 28 ° C., humidity 85%) environment for one day and night. Thereafter, both were mixed and stirred for 60 minutes, and the triboelectric charge amount was measured with a blow-off tribo measuring device (Toshiba Chemical Co., Ltd .: TB-200).
As described above, the absolute value of the obtained charge amount was 24 μC / g.

[Toner Example 2]
In Example 1, the resin particle dispersion was changed from (7) to (8), the colorant particle dispersion was changed from (1) to (2), and the pH when heated at 95 ° C. to 5.0. Toner particles were obtained in the same manner as in Example 1 except that this was maintained.
The cumulative volume average particle diameter D ₅₀ of the toner particles is 4.39 μm, and the volume average particle size distribution index GSDv is 1.19. The shape factor SF1 was slightly spherical with 122.
Further, using this toner particle, an external additive toner was obtained in the same manner as in Example 1, and a developer was further prepared. As a result of performing fixing evaluation, mechanical strength index, and charge measurement in the same manner as in Example 1,
The minimum fixing temperature by rubbing resistance evaluation is 100 ° C.,
The minimum fixing temperature measured by image glossiness was as good as 105 ° C.
Further, the occurrence temperature of hot offset was as good as 220 ° C., and the image quality was also good without any unevenness or fog.
In this example, the image glossiness when fixing at 140 ° C. was as good as 64%.
The mechanical strength index of the toner of this example was as good as 0.14.
The absolute value of the obtained charge amount was 27 μC / g.

[Toner Example 3]
In Example 1, the resin particle dispersion was changed from (7) to (9), the colorant particle dispersion (1) was changed to (3), and the amount of polyaluminum chloride was changed to 0.12 parts by weight. Obtained toner particles in the same manner as in Example 1.
The cumulative volume average particle diameter D ₅₀ of the toner particles is 4.15 μm, the volume average particle size distribution index GSDv is 1.22, the shape factor SF1 is 117, and the toner particles are spherical.
Further, using this toner particle, an external additive toner was obtained in the same manner as in Example 1, and a developer was further prepared. As a result of performing fixing evaluation, mechanical strength index, and charge measurement in the same manner as in Example 1,
The minimum fixing temperature by rubbing resistance evaluation is 105 ° C.,
The minimum fixing temperature measured by image glossiness was as good as 105 ° C.
Further, the occurrence temperature of hot offset was as good as 220 ° C., and the image quality was also good without any unevenness or fog.
In this example, the image glossiness when fixing at 140 ° C. was as good as 62%.
Further, the mechanical strength index of the toner of this example was as good as 0.10.
Further, the absolute value of the obtained charge amount was 28 μC / g.

[Toner Example 4]
Toner particles were obtained in the same manner as in Example 1, except that the colorant particle dispersion (1) was changed to the colorant particle dispersion (4).
The toner particles had a cumulative volume average particle size D ₅₀ of 4.45 μm, a volume average particle size distribution index GSDv of 1.22, and a shape factor SF 1 of 131 potatoes.
Further, using this toner particle, an external additive toner was obtained in the same manner as in Example 1, and a developer was further prepared. As a result of performing fixing evaluation, mechanical strength index, and charge measurement in the same manner as in Example 1,
The minimum fixing temperature by rubbing resistance evaluation is 105 ° C.,
The minimum fixing temperature measured by image glossiness was as good as 105 ° C.
Further, the occurrence temperature of hot offset was as good as 220 ° C., and the image quality was also good without any unevenness or fog.
Further, in this example, the image glossiness when fixing at 140 ° C. was as good as 61%.
Further, the mechanical strength index of the toner of this example was as good as 0.09.
The absolute value of the obtained charge amount was 31 μC / g.

[Toner Comparative Example 1]
(Preparation of toner particles)
In Example 1, toner particles were obtained in the same manner as in Example 1 except that the resin dispersion was changed from (7) to (10) and the pH during heating at 95 ° C. was maintained at 5.0.
The cumulative volume average particle diameter D ₅₀ of the toner particles is 4.39 μm, and the volume average particle size distribution index GSDv is 1.19. The shape factor SF1 was 135, which was a potato shape.
Further, using this toner particle, an external additive toner was obtained in the same manner as in Example 1, and a developer was further prepared. As a result of performing fixing evaluation, mechanical strength index, and charge measurement in the same manner as in Example 1,
The minimum fixing temperature by rubbing resistance evaluation is 125 ° C.,
The minimum fixing temperature by image glossiness measurement was 125 ° C.
The image quality was good with no unevenness or fog, but the hot offset generation temperature was 190 ° C.
In this embodiment, the image glossiness when fixing at 140 ° C. was 59%.
Further, the mechanical strength index of the toner of this example deteriorated to 0.45.
The absolute value of the obtained charge amount was 19 μC / g.

[Toner Comparative Example 2]
In Example 1, toner particles were obtained in the same manner as in Example 1 except that the resin particle dispersion was changed from (7) to (11) and the pH during heating at 95 ° C. was maintained at 5.0.
The cumulative volume average particle diameter D ₅₀ of the toner particles is 4.63 μm, and the volume average particle size distribution index GSDv is 1.20. The shape factor SF1 was 135, which was a potato shape.
Further, using this toner particle, an external additive toner was obtained in the same manner as in Example 1, and a developer was further prepared. As a result of performing fixing evaluation, mechanical strength index, and charge measurement in the same manner as in Example 1,
The minimum fixing temperature by rubbing resistance evaluation is 100 ° C.,
The minimum fixing temperature measured by image glossiness was 100 ° C.
The image quality was uneven and fogging, and the hot offset generation temperature was 190 ° C.
Further, in this embodiment, the image gloss when fixing at 140 ° C. was 69%.
Further, the mechanical strength index of the toner of this example deteriorated to 0.82.
Moreover, the absolute value of the obtained charge amount was 9 μC / g.

[Toner Comparative Example 3]
In Example 1, toner particles were obtained in the same manner as in Example 1 except that the resin particle dispersion was changed from (7) to (12) and the pH during heating at 95 ° C. was maintained at 5.0.
The cumulative volume average particle diameter D ₅₀ of the toner particles is 4.59 μm, and the volume average particle size distribution index GSDv is 1.20. The shape factor SF1 was 131 and became a potato shape.
Further, using this toner particle, an external additive toner was obtained in the same manner as in Example 1, and a developer was further prepared. As a result of performing fixing evaluation, mechanical strength index, and charge measurement in the same manner as in Example 1,
The minimum fixing temperature by rubbing resistance evaluation is 120 ° C.,
The minimum fixing temperature by image glossiness measurement was 120 ° C.
The image quality was good with no unevenness or fogging, but the hot offset generation temperature was 220 ° C.
Further, in this embodiment, the image gloss when fixing at 140 ° C. was 39%, and the gloss was low.
Further, the mechanical strength index of the toner of this example was 0.12, and the absolute value of the obtained charge amount was 39 μC / g.

  The results of Toner Examples 1 to 4 and Toner Comparative Examples 1 to 3 are shown in Tables 1 and 2 below.

The details of the abbreviations in Table 1 above are as shown below.
BPA-EO 2 mol adduct: Bisphenol A-ethylene oxide 2 mol adduct BPA-EO 1 mol adduct: Bisphenol A-ethylene oxide 1 mol adduct BPA: Bisphenol A
St: styrene CHDM: 1,4-cyclohexanedicarboxylic acid TPA-DM: dimethyl terephthalate 1,4-PDAA: 1,4-phenylenediacetic acid TPA: terephthalic acid BA: n-butyl acrylate

  According to Table 1 above, the crystalline polycondensation resin / non-crystalline polycondensation resin is compounded, and the inner core (core) is a crystalline polycondensation resin, and the outside is coated with a part or all of the inner core. The electrostatic charge image developing toner of the present invention using resin particles formed as a coating layer of a conductive polycondensation resin has sharp melt properties and high image gloss while ensuring low-temperature fixability of crystalline resins. It was shown that

Claims (6)

(1) It has a two-layer structure of crystalline resin / non-crystalline resin comprising an inner core containing a crystalline polycondensation resin and a coating layer in which the non-crystalline polycondensation resin covers part or all of the inner core. A resin particle dispersion in which resin particles are dispersed,
(2) A resin obtained by polycondensation of the crystalline resin and / or the amorphous resin in an aqueous medium,
(3) The average layer thickness of the coating layer is 0.01 μm or more and 1.0 μm or less,
(4) The median diameter of the inner core is 0.01 μm or more and 1.0 μm or less,
(5) A resin particle dispersion wherein the median diameter of the resin particles having a two-layer structure of crystalline resin / amorphous resin is 0.02 μm or more and 2.0 μm or less. Obtaining a crystalline resin particle dispersion in which resin particles containing a crystalline polycondensation resin are dispersed in an aqueous medium; and
A resin particle dispersion in which a monomer that forms an amorphous resin is added to the crystalline resin particle dispersion and polycondensed to disperse resin particles in which the inner core is a crystalline resin and the coating layer is an amorphous resin. The manufacturing method of the resin particle dispersion liquid of Claim 1 including the process to obtain. A step of aggregating the resin particles in a dispersion containing at least a resin particle dispersion to obtain aggregated particles; and
A method for producing an electrostatic charge image developing toner comprising a step of heating and aggregating the aggregated particles,
The resin particle dispersion is a resin particle dispersion according to claim 1 or a resin particle dispersion produced by the production method according to claim 2. Method.   An electrostatic image developing toner produced by the production method according to claim 3.   An electrostatic charge image developer comprising the electrostatic charge image developing toner according to claim 4 and a carrier. A latent image forming step of forming an electrostatic latent image on the surface of the latent image holding member;
A developing step of developing the electrostatic latent image formed on the surface of the latent image holding body with a developer containing toner to form a toner image;
A transfer step of transferring the toner image formed on the surface of the latent image carrier to the surface of the transfer target;
A fixing step of thermally fixing the toner image transferred to the surface of the transfer material,
An image forming method using the electrostatic image developing toner according to claim 4 as the toner, or the electrostatic image developer according to claim 5 as the developer.