JP2009229919A - Toner for electrostatic charge image development, manufacturing method of the same, developer for electrostatic charge image development, developer cartridge for electrostatic charge image development, image forming device, and process cartridge - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide toner for electrostatic charge image development which has excellent low temperature fixability and electric charging property, has small charging environmental dependency, can suppress generation of odor, and suppress contamination of a charger, and deterioration of a fixing unit, and to provide a developer for electrostatic charge image development, a developer cartridge for electrostatic charge image development, an image forming device, and a process cartridge, a fixing method, and an image forming method. <P>SOLUTION: The toner for electrostatic charge image development contains at least polyester resin, with an acid number of 5-25 mgKOH/g, and colorant. Ammonium ion content in the toner is 20-400 ppm. A reduced amount of the ammonium ions in the toner when exposed to air at 30°C with humidity of 80% for six hours is ≤120 ppm. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an electrostatic charge developing toner and a method for producing the same, an electrostatic charge developing developer, an electrostatic charge image developing developer cartridge, an image forming apparatus, and a process cartridge.

  A method of visualizing image information through an electrostatic charge image such as electrophotography is currently used in various fields. In conventional electrophotography, an electrostatic latent image is formed on a photosensitive member or an electrostatic recording member by using various means, and electro-sensitive fine particles called toner are adhered to the electrostatic latent image. Generally, a method of visualizing through a plurality of steps of developing an image (toner image), transferring it to the surface of a transfer medium, and fixing it by heating or the like is generally used.

  As a fixing technique for fixing the toner image transferred to the surface of the transfer target, a hot roll fixing is performed in which the transfer target having the toner image transferred is inserted between a pair of rolls including a heating roll and a pressure roll and fixed. The law is common. As a similar technique, a fixing method in which one or both of the rolls is replaced with a belt is also known. Since these techniques are in direct contact with the image as compared with other fixing methods, a fast and robust image can be obtained and the energy efficiency is high.

  In recent years, with the increasing demand for energy saving necessary for image formation, in order to save power in the fixing process, which occupies a certain amount of power, and to expand fixing conditions, the toner fixing temperature must be increased. It is necessary to lower the temperature. By lowering the toner fixing temperature, in addition to the power saving and the expansion of the fixing conditions, the waiting time until the fixing temperature on the surface of the fixing member such as a fixing roll at the time of power input, that is, the so-called warm-up time is shortened. There are significant advantages such as a longer time and longer life of the fixing member.

  On the other hand, with the progress of the advanced information society in recent years, there is an increasing demand for providing information documents constructed by various methods with higher quality images. In order to realize a higher-definition image in color image formation, there is a demand for a toner having a smaller particle size, a narrow particle size distribution and shape distribution, and excellent charging characteristics. At the same time, there is a demand for images with high gloss such as photographic quality and high storage stability.

  By the way, the toner production methods are roughly classified into a conventional dry-type melt-kneading pulverization method and a wet-type method in which the toner is granulated in a liquid. Wet methods are being evaluated from the standpoints of reducing the toner diameter, sharpening the particle size distribution, freedom of shape control, reducing the energy cost of production, and the like. In the wet method, since it is necessary to remove impurities after the toner particles are prepared, for example, the conductivity of water in which the toner manufactured in the wet method is redispersed is set to 1 to 100 μS / cm, or manufactured in the wet method. It has been proposed to improve the chargeability of the toner under high temperature and high humidity by reducing the amount of alkali metal or alkaline earth metal remaining in the toner to 5% by weight or less (for example, patents) Reference 1 and Patent Document 2).

Further, the total ion amount of Na ions, K ions, Ca ions, Mg ions and NH ₄ ions in the dispersion liquid in which the toner is dispersed in water is 0.5 μmol value / g or more and 7.5 μmol value / g or less. It has been proposed to pay attention (for example, see Patent Document 3).
Further, it has been proposed to use a styrene / acrylic resin as the resin and evaluate the ion abundance ratio in the dispersion by ESCA measurement (for example, Patent Document 4 and Patent Document 5).
JP-A-7-319205 Japanese Patent Laid-Open No. 9-218532 JP 2000-330330 A JP-A-9-114125 JP 2001-255700 A

  An object of the present invention is to provide an electrostatic charge image developing toner excellent in low-temperature fixability and chargeability, less dependent on the charging environment, suppressed in odor generation, and suppressed in contamination of the charger and deterioration of the fixing device. To provide a developer for charge development, a developer cartridge for developing an electrostatic image, an image forming apparatus, a process cartridge, a fixing method, and an image forming method.

The above-mentioned subject is achieved by the following present invention.
That is, the invention according to claim 1
At least a polyester resin, a colorant and ammonium ions,
The acid value of the polyester resin is 5 mgKOH / g or more and 25 mgKOH / g or less,
The ammonium ion content in the toner is 20 ppm or more and 400 ppm or less,
An electrostatic charge image developing toner characterized in that the amount of ammonium ion reduction in the toner by exposing the toner to air at 30 ° C. and 80% humidity for 6 hours is 120 ppm or less.

The invention according to claim 2
The toner for developing an electrostatic charge image according to claim 1, wherein the polyester resin contains a crystalline polyester resin.

The invention according to claim 3
Resin for adjusting a resin particle dispersion in which resin particles are dispersed by adding a water-based solvent to a resin-containing liquid containing at least a polyester resin, ammonia and an organic solvent, phase inversion emulsification, and removing the organic solvent A particle dispersion adjusting step;
An aggregated particle forming step of forming aggregated particles containing at least the resin particles;
A toner particle forming step of forming toner particles by heating the aggregated particle dispersion and fusing the aggregated particles;
A cleaning step of cleaning the toner particles;
The method for producing a toner for developing an electrostatic charge image according to claim 1, comprising:

The invention according to claim 4
The cleaning step includes a step of cleaning the toner particles with a treatment liquid having a pH of 9 or more, a pH of 10 or less, a step of cleaning the toner particles with an ion exchange resin while treating with ultrasonic waves after the pH of the toner particles is adjusted to 4 or less, and the toner 4. The method for producing a toner for developing an electrostatic charge image according to claim 3, further comprising a step of washing the particles with ion exchange water.

The invention according to claim 5
An electrostatic charge image developing developer comprising at least the electrostatic charge image developing toner according to claim 1.

The invention according to claim 6
Contains a developer that is detached from the image forming apparatus and supplied to at least developing means provided in the image forming apparatus;
6. The electrostatic charge image developing developer cartridge according to claim 5, wherein the developer is the electrostatic charge image developing developer according to claim 5.

The invention according to claim 7 provides:
An electrostatic latent image carrier;
Charging means for charging the surface of the electrostatic latent image holding member by discharging;
Electrostatic latent image forming means for forming an electrostatic latent image on the surface of the electrostatic latent image holding member;
Developing means for developing the electrostatic latent image into a toner image with a developer;
Transfer means for transferring the toner image on the surface of the electrostatic latent image holding member to the surface of the transfer target;
Fixing means for heating and fixing the toner image transferred to the transfer body,
The image forming apparatus according to claim 5, wherein the developer is the developer for developing an electrostatic image according to claim 5.

The invention according to claim 8 provides:
A developer for storing the developer for developing an electrostatic charge image according to claim 5 and developing the electrostatic latent image formed on the surface of the electrostatic latent image holding member into a toner image by the developer for developing an electrostatic charge image. Means,
An electrostatic latent image holding member, a charging unit for charging the surface of the electrostatic latent image holding member by discharge, and a toner removing unit for removing toner remaining on the surface of the electrostatic latent image holding member. And at least one selected,
A process cartridge is detachable from an image forming apparatus.

  According to the first aspect of the present invention, the low temperature fixing property and the charging property are excellent, the charging environment dependency is small, the generation of odor is suppressed, and the contamination of the charging device and the deterioration of the fixing device are suppressed.

  According to the second aspect of the present invention, since the low temperature fixability is realized, the deterioration of the fixing device is further suppressed.

  According to the third aspect of the invention, a toner having a controlled particle size, particle size distribution, and shape can be obtained, excellent in low-temperature fixability and chargeability, less dependent on charging environment, and odor generation can be suppressed. Thus, a toner in which contamination of the charger and deterioration of the fixing device are suppressed can be obtained.

  According to the fourth aspect of the present invention, there can be obtained a toner that is more excellent in chargeability, suppresses generation of odor, and suppresses contamination of the charger and deterioration of the fixing device.

  According to the fifth aspect of the invention, the low temperature fixing property and the charging property are excellent, the dependency on the charging environment is small, the generation of odor is suppressed, and the contamination of the charging device and the deterioration of the fixing device are suppressed.

  According to the sixth aspect of the present invention, the low temperature fixing property and the charging property are excellent, the dependency on the charging environment is small, the generation of odor is suppressed, and the contamination of the charging device and the deterioration of the fixing device are suppressed.

  According to the seventh aspect of the invention, the low temperature fixing property and the charging property are excellent, the dependency on the charging environment is small, the generation of odor is suppressed, and the contamination of the charging device and the deterioration of the fixing device are suppressed.

  According to the eighth aspect of the present invention, the low temperature fixing property and the charging property are excellent, the dependency on the charging environment is small, the generation of odor is suppressed, and the contamination of the charging device and the deterioration of the fixing device are suppressed.

The present invention will be described in detail below.
<Toner for electrostatic image development>
The electrostatic image developing toner of the present embodiment (hereinafter sometimes simply referred to as “toner”) includes at least a polyester resin having an acid value of 5 mgKOH / g or more and 25 mgKOH / g or less and a colorant. Other components may be included accordingly.
The amount of ammonium ions contained in the toner (ammonium ion content) is 20 ppm or more and 400 ppm or less, and the amount of ammonium ions reduced by exposing the toner to air at 30 ° C. and 80% humidity for 6 hours. The amount (ammonium ion reduction amount) is 0 ppm or more and 120 ppm or less.

When the toner has the above-described configuration, it has excellent low-temperature fixability and chargeability, is less dependent on the charging environment, suppresses odor generation, and suppresses contamination of the charger and deterioration of the fixing device.
The reason is not clear, but is presumed as follows.

  In the present embodiment, since heating is performed at the time of fixing, odor may be generated by releasing ammonia from the inside of the toner. If the toner contains a large amount of ammonium ions, it may be difficult to obtain toner chargeability. However, in this embodiment, since the ammonium ion content is in the above range, the generation of odor during fixing is suppressed, and it is considered that the toner has excellent chargeability.

  Further, as described above, in the present embodiment, since heating is performed at the time of fixing, for example, when a recording medium containing moisture, particularly acidic paper is used, an acid may be released due to the influence of water vapor generated by heating. When the acid thus released comes into contact with the side surface (cut surface) of the heating roll, deterioration of the adhesive layer may be promoted. However, in this embodiment, since the ammonium ion content is in the above range, it is presumed that the acid is neutralized by an appropriate amount of ammonia generated from the inside of the toner by heating at the time of fixing, and the deterioration of the fixing device is suppressed.

In addition, the toner is used by being filled in the developing device in the image forming apparatus. However, if the toner is left in the developing device for a while, the opportunity body is turned off. Since the air stays, the volatile component released from the toner may be filled in the image forming apparatus.
At this time, when ammonia is released from the toner and fills in the image forming apparatus, the released ammonia reacts with water by discharge from a charger (especially a scorotron charger) to produce a reaction product (for example, ammonium nitrate). Etc.) may occur. When the reaction product (for example, ammonium nitrate or the like) adheres to the discharge wire, discharge unevenness occurs to cause uneven charging of the electrostatic latent image holding member, which may cause image unevenness.

  In particular, at a high temperature (for example, 30 ° C.), ammonia contained in the toner surface is more easily released into the air than at a low temperature (for example, 10 ° C.). Contamination is likely to occur. In particular, under high humidity (for example, 80% humidity), moisture in the air tends to condense on the discharge wire as compared with low humidity (for example, 15%). Conceivable. Further, the occurrence of image unevenness due to the discharge unevenness of the charger is considered to be particularly noticeable in a low density area image.

  On the other hand, in this embodiment, since the amount of ammonium ion reduction is in the above range, it is presumed that the charger contamination due to the ammonia released from the toner as described above is suppressed even under high temperature and high humidity.

  In this embodiment, since the toner contains a polyester resin, it is considered that the low-temperature fixability is good. When the low-temperature fixability of the toner is good, the heating temperature in the fixing step can be kept low, and the amount of ammonia released from the toner in the fixing step is small, so that the odor can be further suppressed. Even if the amount of ammonia released in the fixing process is small, the heating temperature is low, so that deterioration of the fixing device is suppressed.

Furthermore, in the present embodiment, it is considered that the acid value of the polyester resin contained in the toner is in the above range, so that the chargeability is excellent, and the change in the environment hardly affects the chargeability.
Hereinafter, the ammonium ions in the toner will be described.

-Ammonium ion-
As described above, the ammonium ion content in the toner is 20 ppm to 400 ppm, preferably 25 ppm to 350 ppm, and more preferably 30 ppm to 300 ppm.
Further, the amount of ammonium ion reduction in the toner is 0 ppm or more and 120 ppm or less as described above, preferably 0 ppm or more and 100 ppm or less, and more preferably 0 ppm or more and 80 ppm or less.

Here, the reduced amount of ammonium ions refers to the amount of ammonium ions in the toner that is reduced by exposing the toner to air at 30 ° C. and 80% humidity for 6 hours. That is, assuming that the amount of ammonium ions (ammonium ion content) contained in the toner before exposure is C _B (ppm) and the amount of ammonium ions contained in the toner after exposure is C _A (ppm), The reduced ammonium ion amount C _D (ppm) is represented by the following formula.
Formula: C _D (ppm) = C _B (ppm) −C _A (ppm)

As a method for exposing the toner, specifically, for example, 1.0 g of the toner before the exposure is uniformly spread so as to have an area of 25 cm ^2, and the toner is exposed to air at a temperature of 30 ° C. and a humidity of 80%. The method of leaving still for 6 hours is mentioned.

Measurement of the ammonium ion content in the toner is performed as follows. Specifically, the content of ammonium ions in the toner is obtained by dispersing the toner in water and extracting ammonia in the water, and then analyzing by ion chromatography.
As for the ammonium ion reduction amount in the toner, the measuring method similar to the method of the ammonium ion content, and measuring the C _B values and C _A value, finding the C _D value from the above equation.

As a method for simultaneously controlling the ammonium ion content in the toner and the ammonium ion reduction amount in the toner, for example, the amount of ammonium ions contained in the toner surface and the amount of ammonium ions contained in the toner are simultaneously controlled. The method of controlling is mentioned.
Here, in the present embodiment, the toner surface refers to a layer between the outermost surface of the toner particles and a depth of about 2 μm, and the inside of the toner is the core of the toner excluding the toner surface. Say the part.

Ammonium ions contained in the toner surface are easily released into the air as ammonia when the toner particles are exposed to the air under high temperature and high humidity (for example, temperature 30 ° C., humidity 80 ° C.).
On the other hand, ammonium ions contained in the toner are easily released into the air as ammonia when the toner is heated in the fixing step of image formation, but are not easily released when exposed to the air.

Therefore, for example, if the amount of ammonium ions contained in the toner is large and the amount of ammonium ions contained in the toner surface is controlled to be small, the toner has a high ammonium ion content and a low ammonium ion reduction amount. Is obtained.
In this way, by simultaneously controlling the amount of ammonium ions contained in the toner surface and inside the toner, the ammonium ion content and the ammonium ion reduction amount are simultaneously controlled.

Here, the amount of ammonium ions contained in the toner surface is measured as follows. Specifically, as a method of dispersing the toner in water in the measurement of the amount of ammonium ions described above, ultrasonic dispersion is performed at 25 ° C., ammonium ions are extracted into water, and then analyzed by ion chromatography. Can be sought.
Further, the amount of ammonium ions contained in the toner is measured as follows. Specifically, as a method for dispersing toner in water in the above-described measurement of the amount of ammonium ions, ultrasonic dispersion is performed at a temperature higher than the glass transition point of the resin contained in the toner, and ammonium ions are extracted into water. After that, by analyzing by ion chromatography, the content of ammonium ions contained in the whole toner is obtained, and the amount of ammonium ions contained in the toner is obtained by subtracting the amount of ammonium ions contained in the toner surface. be able to. Moreover, when it contains crystalline polyester resin, it is preferable to ultrasonically disperse at a temperature higher than its melting point.

  As a method for simultaneously controlling the amount of ammonium ions contained in the toner surface and in the toner, for example, in the toner production method described later, depending on the amount of ammonia used in the resin particle dispersion adjustment step, the operating conditions of the washing step, etc. The method of controlling is mentioned.

  Hereinafter, each composition component will be described.

-Binder resin-
The binder resin contains at least a polyester resin. As described above, the acid value of the polyester resin is 5 mgKOH / g or more and 25 mgKOH / g or less, and preferably 6 mgKOH / g or more and 23 mgKOH / g or less.

  When the acid value of the polyester resin is 5 mgKOH / g or more, the toner has good affinity for paper and good chargeability. In addition, when the toner is produced by the emulsion aggregation method described later, it is easy to produce the emulsion particles, and it is possible to suppress the aggregation speed in the aggregation process and the shape change speed in the coalescence process from being significantly increased. Easy shape control.

  Further, since the acid value of the polyester resin is within 25 mgKOH / g, it is difficult to adversely affect the environmental dependency of charging. Further, when the toner is produced by the emulsion aggregation method described later, it is possible to prevent the aggregation speed in the aggregation process and the shape change speed in the coalescence process from being remarkably slow, thereby preventing a decrease in productivity. .

The polyester resin is obtained, for example, mainly by condensation polymerization of polyvalent carboxylic acids and polyhydric alcohols.
Examples of the polyvalent carboxylic acid include terephthalic acid, isophthalic acid, phthalic anhydride, trimellitic anhydride, pyromellitic acid, naphthalenedicarboxylic acid, and other aromatic carboxylic acids; maleic anhydride, fumaric acid, succinic acid, Examples thereof include aliphatic carboxylic acids such as alkenyl succinic anhydride and adipic acid; alicyclic carboxylic acids such as cyclohexanedicarboxylic acid, and one or more of these polyvalent carboxylic acids can be used.
Among these polyvalent carboxylic acids, it is preferable to use an aromatic carboxylic acid. In order to ensure good fixability, the polyester resin preferably has a cross-linked structure or a branched structure. To that end, a trivalent or higher carboxylic acid (trimellitic acid or tricarboxylic acid) is used as a polyvalent carboxylic acid together with a dicarboxylic acid. It is preferable to use the acid anhydride or the like together.

Examples of the polyhydric alcohol include aliphatic diols such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, butanediol, hexanediol, neopentylglycol, and glycerin; cyclohexanediol, cyclohexanedimethanol, hydrogenated bisphenol And alicyclic diols such as A; aromatic diols such as ethylene oxide adduct of bisphenol A and propylene oxide adduct of bisphenol A. One or more of these polyhydric alcohols can be used.
Among these polyhydric alcohols, aromatic diols and alicyclic diols are preferable, and among these, aromatic diols are more preferable. In order to secure better fixing properties, it is preferable that the polyester resin has a cross-linked structure or a branched structure. Therefore, as the polyhydric alcohol, a trihydric or higher polyhydric alcohol (glycerin, trimethylolpropane) is used together with the diol. , Pentaerythritol) may be used in combination.

The glass transition temperature (hereinafter sometimes abbreviated as “Tg”) of the polyester resin is preferably 40 ° C. or higher and 80 ° C. or lower, and more preferably 50 ° C. or higher and 70 ° C. or lower. When the Tg of the polyester resin is 80 ° C. or lower, low-temperature fixability is obtained, and when the Tg is 40 ° C. or higher, sufficient heat storage properties and storability of fixed images are obtained.
Further, the molecular weight (weight average molecular weight; Mw) of the polyester resin is preferably 5,000 or more and 40,000 or less from the viewpoints of resin manufacturability, fine dispersion during toner production, and compatible toner during melting.

(Crystalline polyester resin)
The polyester resin preferably contains a crystalline polyester resin. When the polyester resin contains the crystalline polyester resin, the low-temperature fixability of the toner becomes better, so the amount of ammonia released from the toner in the fixing step is reduced, and the odor is further suppressed. Even if the amount of ammonia released in the fixing process is small, the heating temperature is low, so that deterioration of the fixing device is suppressed.
When the polyester resin contains a crystalline polyester resin and an amorphous polyester resin, the crystalline polyester resin is compatible with the amorphous polyester resin at the time of melting, and the viscosity of the toner is significantly reduced. A toner with excellent properties can be obtained.
Among crystalline polyester resins, aliphatic crystalline polyester resins are particularly preferable because many of them have a preferable melting point compared to aromatic crystalline resins.

  The content of the crystalline polyester resin in the polyester resin is preferably 2% by mass or more and 20% by mass or less, and more preferably 2% by mass or more and 14% by mass or less. When the content of the crystalline polyester resin is 2% by mass or more, the non-crystalline polyester resin can be sufficiently reduced in viscosity at the time of melting, and an improvement in low-temperature fixability is easily obtained. Further, if the content of the crystalline polyester resin is 20% by mass or less, the deterioration of the charging property of the toner due to the presence of the crystalline polyester resin can be suppressed, so the image strength after fixing on the recording medium Is easy to obtain.

  The melting point of the crystalline polyester resin is preferably in the range of 50 ° C. or higher and 100 ° C. or lower, preferably in the range of 55 ° C. or higher and 95 ° C. or lower, and more preferably in the range of 60 ° C. or higher and 90 ° C. or lower. . If the melting point of the crystalline polyester resin is 50 ° C. or higher, the storage stability of the toner and the storage stability of the toner image after fixing are good, and if it is 100 ° C. or lower, the low-temperature fixability is easily improved.

Note that the “crystalline polyester resin” in the present embodiment refers to a clear endothermic change rather than a step-like endothermic amount change in differential scanning calorimetry (hereinafter sometimes abbreviated as “DSC”). It has a peak. The crystalline polyester resin is a polymer obtained by copolymerizing other components with respect to the main chain. When the other components are 50% by mass or less, this copolymer is also called a crystalline polyester resin.
In this embodiment, when the polyester resin is a mixture of a crystalline polyester resin and an amorphous polyester resin, the “acid value of the polyester resin” indicates the acid value of the mixture.

  The crystalline polyester resin is synthesized from an acid (dicarboxylic acid) component and an alcohol (diol) component. In the following, the “acid-derived component” is a polyester resin, and before the polyester resin is synthesized. The component part which was an acid component is pointed out, and the "alcohol-derived component" refers to the component part which was an alcohol component before the synthesis of the polyester resin.

[Acid-derived components]
Examples of the acid to be the acid-derived constituent component include various dicarboxylic acids, but the acid-derived constituent component in the crystalline polyester resin according to the embodiment is preferably a linear aliphatic dicarboxylic acid.
For example, succinic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelic acid, sebacic acid, 1,9-nonanedicarboxylic acid, 1,10-decanedicarboxylic acid, 1,11-undecanedicarboxylic acid Acid, 1,12-dodecanedicarboxylic acid, 1,13-tridecanedicarboxylic acid, 1,14-tetradecanedicarboxylic acid, 1,16-hexadecanedicarboxylic acid, 1,18-octadecanedicarboxylic acid, etc., or lower alkyl esters thereof, An acid anhydride may be mentioned, but not limited thereto. Among these, adipic acid, sebacic acid, and 1,10-decanedicarboxylic acid are preferable in consideration of availability.

  As the acid-derived constituent component, other constituent components such as a dicarboxylic acid-derived constituent component having a double bond and a dicarboxylic acid-derived constituent component having a sulfonic acid group may be contained.

  In the present specification, “constituent mol%” means that the acid-derived constituent component in the entire acid-derived constituent component in the polyester resin or the alcohol constituent component in the entire alcohol-derived constituent component is 1 unit (mol). ) Indicates the percentage.

[Alcohol-derived components]
As the alcohol for becoming an alcohol component, an aliphatic diol is desirable. For example, ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-dodecanediol, 1,12-undecanediol, 1,13-tridecanediol, Examples include, but are not limited to, 1,14-tetradecanediol, 1,18-octadecanediol, 1,20-eicosanediol, and the like. Among these, 1,4-butanediol, 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, and 1,10-decanediol are preferable in view of availability and cost.

  The molecular weight (weight average molecular weight; Mw) of the crystalline polyester resin is preferably 8,000 or more and 40,000 or less from the viewpoint of resin manufacturability, fine dispersion during toner production, and compatible toner during melting, More preferably, it is 10,000 or more and 30,000 or less. If it is 8,000 or more, the resistance reduction of the crystalline polyester resin can be suppressed, so that the charging property can be prevented from decreasing. If it is 40,000 or less, the cost of resin synthesis is suppressed, and the low-temperature fixability is not adversely affected in order to prevent a decrease in sharp melt properties.

  In the embodiment, the molecular weight of the polyester resin was measured and calculated by GPC (Gel Permeation Chromatography). Specifically, HPC-8120 manufactured by Tosoh Corporation was used for GPC, TSKgel SuperHM-M (15 cm) manufactured by Tosoh Corporation was used for the column, and the polyester resin was measured with a THF solvent. Next, the molecular weight of the polyester resin was calculated using a molecular weight calibration curve prepared with a monodisperse polystyrene standard sample.

(Production method of polyester resin)
There is no restriction | limiting in particular as a manufacturing method of a polyester resin, It can manufacture with the general polyester polymerization method which makes an acid component and an alcohol component react. For example, direct polycondensation, transesterification, and the like are used depending on the type of monomer. The molar ratio (acid component / alcohol component) at the time of reacting the acid component with the alcohol component varies depending on the reaction conditions and the like, and thus cannot be generally described. However, in order to increase the molecular weight, it is usually 1/1. The degree is preferred.

  Catalysts that can be used in the production of the polyester resin include alkali metal compounds such as sodium and lithium; alkaline earth metal compounds such as magnesium and calcium; metal compounds such as zinc, manganese, antimony, titanium, tin, zirconium, and germanium; Examples thereof include phosphorous acid compounds; phosphoric acid compounds; and amine compounds.

In addition to the polyester resin, other resins may be used in combination as the binder resin. Other resins include: ethylene resins such as polyethylene and polypropylene; styrene resins such as polystyrene and α-polymethylstyrene; (meth) acrylic resins such as polymethyl methacrylate and polyacrylonitrile; polyamide resins and polycarbonate resins; Examples thereof include polyether resins and copolymer resins thereof. However, the content of the polyester resin in the binder resin is preferably 60% or more.

-Colorant-
The toner according to the exemplary embodiment includes a colorant. The colorant may be a dye or a pigment, but is preferably a pigment from the viewpoint of light resistance and water resistance.
For example, carbon black, aniline black, aniline blue, calcoil blue, chrome yellow, ultramarine blue, dupont oil red, quinoline yellow, methylene blue chloride, phthalocyanine blue, malachite green oxalate, lamp black, rose bengal, quinacridone, benzy Thin Yellow, C.I. I. Pigment red 48: 1, C.I. I. Pigment red 57: 1, C.I. I. Pigment red 122, C.I. I. Pigment red 185, C.I. I. Pigment red 238, C.I. I. Pigment yellow 12, C.I. I. Pigment yellow 17, C.I. I. Pigment yellow 180, C.I. I. Pigment yellow 97, C.I. I. Pigment yellow 74, C.I. I. Pigment blue 15: 1, C.I. I. A known pigment such as CI Pigment Blue 15: 3 can be used.

As content of a coloring agent, 1 to 30 mass parts is preferable with respect to 100 mass parts of binder resin.
It is also effective to use a colorant that has been surface-treated as necessary, or a pigment dispersant. By appropriately selecting the type of the colorant, yellow toner, magenta toner, cyan toner, black toner and the like can be obtained.

-Release agent-
The toner of the exemplary embodiment may contain a release agent as necessary. Examples of the release agent include paraffin wax such as low molecular weight polypropylene and low molecular weight polyethylene; silicone resin; rosins; rice wax; carnauba wax; The melting point of these release agents is preferably 50 ° C. or higher and 100 ° C. or lower, and more preferably 60 ° C. or higher and 95 ° C. or lower.
The content of the release agent in the toner is desirably 0.5% by mass or more and 15% by mass or less, and more desirably 1.0% by mass or more and 12% by mass or less. If the content of the release agent is 0.5% by mass or more, it is possible to prevent a peeling failure particularly in the case of oilless fixing. If the content of the release agent is 15% by mass or less, deterioration of toner fluidity can be prevented, so that image quality and reliability of image formation can be maintained.

-Other additives-
In addition to the above-described components, various components such as an internal additive, a charge control agent, inorganic powder (inorganic particles), and organic particles may be further added to the toner in the exemplary embodiment as necessary. it can.

  Examples of the internal additive include metals such as ferrite, magnetite, reduced iron, cobalt, nickel, and manganese, alloys, and magnetic materials such as compounds containing these metals.

  Examples of the charge control agent include quaternary ammonium salt compounds, nigrosine compounds, dyes composed of complexes of aluminum, iron, chromium, and triphenylmethane pigments.

  The inorganic particles are added for various purposes, but may be added for adjusting the viscoelasticity of the toner. By adjusting the viscoelasticity, it is possible to adjust the image glossiness and the penetration into the paper. As the inorganic particles, for example, known inorganic particles such as silica particles, titanium oxide particles, alumina particles, cerium oxide particles, or those obtained by hydrophobizing the surface thereof can be used alone or in combination of two or more kinds. However, silica particles having a refractive index smaller than that of the binder resin are preferably used from the viewpoint that transparency such as color developability and OHP permeability is not impaired. Further, the silica particles may be subjected to various surface treatments, and for example, those subjected to surface treatment with a silane coupling agent, a titanium coupling agent, a silicone oil or the like are preferably used.

-External additive-
In the present embodiment, an external additive such as a fluidizing agent or an auxiliary agent may be added to the toner surface. Examples of external additives include known particles such as silica particles whose surfaces have been hydrophobized, titanium oxide particles, alumina particles, cerium oxide particles, inorganic particles such as carbon black, and polymer particles such as polycarbonate, polymethyl methacrylate, and silicone resin. Can be used. Among these, two or more kinds of external additives are used, and at least one of the external additives preferably has an average primary particle diameter in the range of 30 nm to 200 nm, and more preferably in the range of 30 nm to 180 nm. .

  By reducing the particle size of the toner, non-electrostatic adhesion to the photosensitive member increases, which may cause transfer defects and image loss of fine lines and cause transfer unevenness such as superimposed images. The transferability can be improved by adding a large external additive having an average primary particle size of 30 nm to 200 nm.

  If the average primary particle diameter of the external additive is smaller than 30 nm, the initial toner fluidity is good, but the non-electrostatic adhesion between the toner and the photoreceptor cannot be sufficiently reduced, and the transfer efficiency is low. In some cases, image drop may occur and the image may be lost or the uniformity of the image may be deteriorated. Further, external additive particles are embedded in the toner surface due to stress in the developing device over time, and the chargeability may change, causing problems such as a decrease in copy density and fogging on the background. When the average primary particle diameter of the external additive is larger than 200 nm, it may be easily detached from the toner surface and may cause deterioration of fluidity.

-Toner characteristics-
Furthermore, the toner according to the exemplary embodiment preferably has an average circularity in the range of 0.960 to 0.980, and more preferably in the range of 0.960 to 0.970. As for the shape of the toner, a spherical toner is advantageous in terms of developability and transferability, but it may be inferior to an indeterminate shape in terms of cleaning properties. When the toner has a shape in the above-described range, transfer efficiency and image density can be improved, high-quality image formation can be performed, and the surface of the photoreceptor can be improved.

  Further, the volume average particle size of the toner according to the exemplary embodiment is desirably 3 μm or more and 9 μm or less, more desirably 3.5 μm or more and 8.5 μm or less, and further desirably 4 μm or more and 8 μm or less. If the volume average particle diameter is 3 μm or more, a decrease in toner fluidity can be suppressed, and the chargeability of each particle can be easily maintained. In addition, the charge distribution does not spread, preventing fogging on the background and preventing toner from spilling from the developer. Further, when the volume average particle diameter of the toner is 3 μm or more, the cleaning property is improved. If the volume average particle size is 9 μm or less, a decrease in resolution can be suppressed, so that a sufficient image quality can be obtained and the recent demand for high image quality can be satisfied.

As the particle size distribution index of the toner, the volume average particle size distribution index GSDv is preferably 1.30 or less, more preferably 1.15 or more and 1.28 or less, and 1.17 or more and 1.26 or less. More preferably it is. If GSDv is larger than the above range, the sharpness and resolution of the image may decrease.
The number average particle size distribution index GSDp is preferably 1.30 or less. If GSDp is larger than the above range, the ratio of the small particle size toner becomes high, and electrostatic control may be difficult.

Incidentally, the volume average particle diameter D ₅₀ is, for example, Coulter Counter TAII, Multisizer II - in (Beckman Coulter) the measured particle size ranges which are divided based on the particle size distribution measuring apparatus such as a (channel) On the other hand, a cumulative distribution is drawn from the smaller diameter side for each volume and number, and the particle size that is 16% cumulative is the volume D _16v and number D _16P , and the particle size that is 50% cumulative is the volume D _50v , number D _50P , and cumulative 84 % Particle size is defined as volume D _84v and number D _84P . Using these, the volume average particle size distribution index (GSDv) is calculated as ( _D84v / _D16V ) ^1/2 .

  The SF1 is quantified mainly by analyzing a microscope image or a scanning electron microscope (SEM) image using an image analyzer, and can be calculated as follows, for example. That is, an optical microscope image of higher alcohol particles dispersed on the surface of the slide glass is taken into a Luzex image analyzer through a video camera, and the maximum length and projected area of 100 particles are obtained, calculated by the above equation (1), and the average Obtained by determining the value.

<Method for producing toner for developing electrostatic charge>
The toner manufacturing method in the present embodiment is a method of forming toner particles by a wet manufacturing method (for example, aggregation coalescence method, suspension polymerization method, dissolution suspension granulation method, dissolution suspension method, dissolution emulsion aggregation aggregation method, etc.). And a step of washing the toner particles.
As a method for forming toner particles, as described above, a wet production method for producing toner particles in an aqueous medium is preferable, but an emulsion aggregation method is particularly desirable, and an emulsion aggregation method using a phase inversion emulsification method is more desirable. .

  The emulsion aggregation method is a method of preparing dispersions (emulsion liquid, pigment dispersion liquid, etc.) each containing components (binder resin, colorant, etc.) contained in the toner, and mixing these dispersion liquids to combine the toner components. In this method, aggregated particles are produced by agglomeration, and then the aggregated particles are heated to the melting point or glass transition temperature of the binder resin or higher to thermally fuse the aggregated particles.

The emulsion aggregation method makes it easier to produce toner with a smaller particle size and has a narrower particle size distribution compared to the dry kneading and pulverization method and other wet methods such as the melt suspension method and the dissolution suspension method. Easy to obtain. Further, the shape control is easier than in the melt suspension method, the dissolution suspension method, and the like, and a uniform amorphous toner can be produced. Further, the structure of the toner, such as film formation, is controlled, and when a release agent or a crystalline polyester resin is contained, exposure of these surfaces is suppressed, so that deterioration of chargeability and storage stability is prevented.
Furthermore, in the present embodiment, since a polyester resin having an acid value of 5 mgKOH / g or more and 25 mgKOH / g or less is used, when a toner is prepared by an emulsion aggregation method, resin particle stability in a resin particle dispersion described later is improved, and small particles A toner having an excellent diameter and particle size distribution is produced.

In the emulsion aggregation method, as a method of preparing a dispersion liquid (emulsion liquid) containing a polyester resin contained in a toner, for example, a phase inversion emulsification method, a melt emulsification method (a mixture of an aqueous medium and a resin, For example, a method of applying an shearing force to prepare an emulsion).
In the present embodiment, it is preferable to use a phase inversion emulsification method as a method for preparing the emulsion. By using the phase inversion emulsification method as the method for preparing the emulsion, the hydrolysis of the resin in the toner production process is suppressed, and the particle size of the resin particles in the emulsion is easily controlled. A toner having a good distribution can be obtained at low cost.

  In this embodiment, it is preferable to use a phase inversion emulsification method using ammonia as a neutralizing agent. By performing phase inversion emulsification using ammonia as a neutralizing agent, hydrolysis of the resin during the toner production process is suppressed, and the particle size of the resin particles in the resin particle dispersion is easy to control. Thus, a toner having a good particle size distribution can be obtained at low cost. In addition, a phase inversion emulsification using ammonia as a neutralizing agent, that is, a toner in which ammonium ions are incorporated into the resin particles by adding water to a polyester resin solution containing ammonium ions to thereby incorporate ammonium ions. Is obtained.

On the other hand, toner particles produced by phase inversion emulsification using ammonia as a neutralizing agent may contain ammonium ions not only inside the toner particles but also on the toner particle surface, and the amount of ammonium ion reduction may increase. When image formation is performed using such toner particles as they are, charger contamination due to volatilized ammonia is likely to occur as described above.
Therefore, in the present embodiment, it is preferable to perform the cleaning process of the present embodiment, which will be described later, as the process of cleaning the toner particles. As a result, the amount of reduced ammonium ions in the toner can be kept low, so that contamination of the charger is suppressed.
Hereinafter, the production process of toner particles using the phase inversion emulsification method and the emulsion aggregation method and the step of washing the toner particles (washing step) will be described in detail.

-Emulsification process (resin particle dispersion adjustment process)-
As described above, it is desirable to use the phase inversion emulsification method in the resin particle dispersion adjusting step.
In the phase inversion emulsification method, a neutralizing agent or a dispersion stabilizer is added to an organic continuous phase (Oil phase; O) obtained by dissolving a resin to be dispersed in an organic solvent in which the resin is soluble. Add. Then, an aqueous solvent (Water phase; W) is added dropwise with stirring, and the water in oil (W / O) system is changed to an oil in water (O / W) system, thereby existing in the organic continuous phase. The obtained resin is phase-inverted into a discontinuous phase to obtain an emulsion. Thereafter, the organic solvent in the emulsion is removed, and a resin particle dispersion in which the resin is dispersed and stabilized in the form of particles in an aqueous solvent is obtained. At this time, the order of adding the neutralizing agent and the dispersion stabilizer may be changed.

  Examples of the organic solvent (resin dissolving solvent) for dissolving the resin include formic acid esters, acetic acid esters, butyric acid esters, ketones, ethers, benzenes, and halogenated carbons.

  Specifically, alkyl (methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, t-butyl, etc.) esters such as formic acid, acetic acid, butyric acid, acetone, MEK, MPK, MIPK, Methyl ketones such as MBK and MIBK, ethers such as diethyl ether and diisopropyl ether, heterocyclic substituents such as toluene, xylene and benzene, carbon tetrachloride, methylene chloride, 1,2-dichloroethane, 1,1,2- Halogenated carbons such as trichloroethane, trichloroethylene, chloroform, monochlorobenzene, dichloroethylidene, etc. can be used singly or in combination of two or more, but they are easily available, easy to recover during solvent removal, From the point of consideration, acetates, methyl ketones, Le acids is usually preferably used, in particular, acetone, methyl ethyl ketone, acetic acid, ethyl acetate, butyl acetate is preferred. If the organic solvent remains in the resin particles, it may become a VOC causative substance, and therefore, it is preferable to use a solvent having a relatively high volatility.

  As the aqueous solvent, ion-exchanged water is basically used, but a water-soluble organic solvent may be included so as not to destroy the oil droplets.

  Examples of the water-soluble organic solvent include methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, t-butanol, 1-pentanol, and other short carbon chain alcohols; ethylene glycol monomethyl ether, Examples include ethylene glycol monoalkyl ethers such as ethylene glycol monoethyl ether and ethylene glycol monobutyl ether; ethers, diols, THF, acetone and the like.

When the water-based solvent contains a water-soluble organic solvent, the total content of the water-soluble organic solvent in the water-based solvent is selected in the range of 1% to 50%, more preferably 1% to 30%. Is done.
Further, the water-soluble organic solvent may be used by being added to the resin solution as well as being mixed with the ion exchange water to be added. In the case of adding a water-soluble organic solvent, the wettability between the resin and the resin dissolving solvent can be adjusted, and a function of reducing the liquid viscosity after the resin is dissolved can be expected.

  As a neutralizing agent added for adjusting the pH of the organic continuous phase, general acids such as nitric acid, hydrochloric acid, sodium hydroxide, ammonia, and alkalis can be used. As described above, in the present exemplary embodiment, ammonia is preferably used as a neutralizing agent from the viewpoint of containing ammonium ions in the toner.

  In addition, as described above, a dispersant may be added to the resin solution and the aqueous component as necessary so that the emulsion is stably dispersed.

Examples of the dispersant are those that form a hydrophilic colloid in an aqueous component, and in particular, cellulose derivatives such as hydroxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose; polyvinyl alcohol, polyvinyl pyrrolidone, polyacrylamide, polyacrylic. Examples thereof include synthetic polymers such as acid salts and polymethacrylates, and dispersants such as gelatin, gum arabic and agar.
Moreover, solid fine powders, such as a silica, a titanium oxide, an alumina, a tricalcium phosphate, a calcium carbonate, a calcium sulfate, barium carbonate, can be used as a dispersing agent, for example.

  These dispersants are usually added so that the concentration in the aqueous component is 0 to 20% by mass, preferably 0 to 10% by mass.

A surfactant is also used as the dispersant.
As examples of the surfactant, those according to those used in the colorant dispersion described later can be used.

  As surfactants, for example, in addition to natural surfactant components such as saponins, cationic surfactants such as alkylamine hydrochlorides / acetates, quaternary ammonium salts, glycerols, fatty acid soaps, sulfates, alkyls Anionic surfactants such as naphthalene sulfonates, sulfonates, phosphoric acid, phosphate esters, sulfosuccinates and the like can be mentioned, and anionic surfactants and nonionic surfactants are preferably used.

  As a method for removing the organic solvent from the emulsion, a method of volatilizing the organic solvent at room temperature (15 ° C. or higher and 35 ° C. or lower) or heating, and a method of combining this with reduced pressure are preferably used.

  The volume average particle size of the resin particles in the resin particle dispersion is preferably in the range of 0.08 μm to 0.8 μm, more preferably 0.09 μm to 0.6 μm, and further preferably 0.10 μm to 0.5 μm. desirable. If the volume average particle diameter of the resin particles is 0.08 μm or more, the resin particles are likely to aggregate. If the volume average particle size of the resin particles is 0.8 μm or less, the particle size distribution of the toner is difficult to spread and precipitation of the emulsified particles can be suppressed, so that the storage stability of the emulsified particle dispersion is improved.

  The solid content in the resin particle dispersion is preferably 5 parts by weight or more and 40 parts by weight or less, more preferably 10 parts by weight or more and 30 parts by weight or less with respect to 100 parts by weight of the resin particle dispersion. More preferably, it is 15 to 25 parts by mass.

  If the solid content is less than 5 parts by mass, the viscosity of the resin particle dispersion is lowered and the stability of the particles is deteriorated, which may be undesirable in terms of transportation costs. On the other hand, when the solid content exceeds 40 parts by mass, the viscosity increases excessively, the uniformity of stirring is lost, and particle agglomeration may occur, which may be inconvenient.

-Other particle dispersion adjustment process-
Before entering the agglomeration step described below, a dispersion in which a colorant, a release agent, or the like, which is a toner component other than the binder resin, is dispersed as necessary may be prepared.
In addition to the method of preparing a dispersion corresponding to each component such as a binder resin and a colorant, for example, when preparing an emulsion of a certain component, other components may be added to the solvent to add two or more The components may be emulsified at the same time so that the dispersed particles contain a plurality of components.

The colorant particle dispersion is prepared by a known method. For dispersion of the colorant particles, for example, a rotary shear type homogenizer, a media type disperser such as a ball mill, a sand mill, or an attritor, a high-pressure opposed collision type dispersion is used. A machine or the like is preferably used.
Also, a colorant particle dispersion can be prepared by using a polar ionic surfactant and dispersing it in an aqueous solvent using a homogenizer as described above.

  The volume average particle diameter of the colorant particles in the colorant particle dispersion is desirably 1 μm or less in order to facilitate adjusting the volume average particle diameter and particle size distribution of the toner particles to desired values. It is more desirable that the thickness be 100 nm or more and 300 nm or less.

  The release agent particle dispersion includes, for example, an ionic surfactant, a polymer electrolyte such as a polymer acid or a polymer base, and the above release agent dispersed in water, heated to a temperature higher than the melting temperature, For example, a release agent dispersion containing release agent particles having a particle diameter of 1 μm or less can be prepared by adjusting the particle size with a homogenizer or a pressure discharge type dispersing machine.

  The volume average particle size of the release agent particles in the release agent particle dispersion is 1 μm or less in order to easily adjust the volume average particle size and particle size distribution of the toner particles to desired values. Desirably, it is more desirably 100 nm or more and 300 nm or less.

A surfactant can be used for the purpose of stabilizing the dispersion of each dispersion.
Examples of the surfactant include anionic surfactants such as sulfate, sulfonate, phosphate, and soap; cationic surfactants such as amine salt type and quaternary ammonium salt type; polyethylene glycol And nonionic surfactants such as polyphenols, alkylphenol ethylene oxide adducts, and polyhydric alcohols. Among these, an ionic surfactant is preferable, and an anionic surfactant and a cationic surfactant are more preferable. The said surfactant may be used individually by 1 type, and may be used in combination of 2 or more type.

  Specific examples of anionic surfactants include, for example, fatty acid soaps such as potassium laurate, sodium oleate, and castor oil sodium; sulfate esters such as octyl sulfate, lauryl sulfate, lauryl ether sulfate, and nonylphenyl ether sulfate; Sodium alkylnaphthalene sulfonate such as lauryl sulfonate, dodecyl benzene sulfonate, triisopropyl naphthalene sulfonate, dibutyl naphthalene sulfonate; naphthalene sulfonate formalin condensate, monooctyl sulfosuccinate, dioctyl sulfosuccinate, lauric acid amide sulfonate, oleic acid amide sulfonate, etc. Sulfonates: lauryl phosphate, isopropyl phosphate, nonylphenyl Phosphoric acid esters such as chromatography ether phosphates; dialkyl sulfosuccinate salts such as sodium dioctyl sulfosuccinate; sulfosuccinate salts such as sulfosuccinate lauryl disodium; and the like.

  Specific examples of the cationic surfactant include amine salts such as laurylamine hydrochloride, stearylamine hydrochloride, oleylamine acetate, stearylamine acetate, stearylaminopropylamine acetate; lauryltrimethylammonium chloride, dilauryl Dimethylammonium chloride, distearyldimethylammonium chloride, distearyldimethylammonium chloride, lauryldihydroxyethylmethylammonium chloride, oleylbispolyoxyethylenemethylammonium chloride, lauroylaminopropyldimethylethylammonium ethosulphate, lauroylaminopropyldimethylhydroxyethylammonium perchlorate , Alkylbenzene trimethyl ammonium chlora De, quaternary ammonium salts such as alkyl trimethyl ammonium chloride; and the like.

  Specific examples of the nonionic surfactant include alkyl ethers such as polyoxyethylene octyl ether, polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether; polyoxyethylene octyl phenyl ether, Alkylphenyl ethers such as polyoxyethylene nonylphenyl ether; alkyl esters such as polyoxyethylene laurate, polyoxyethylene stearate, polyoxyethylene oleate; polyoxyethylene lauryl amino ether, polyoxyethylene stearyl amino ether, poly Alkylamines such as oxyethylene oleyl amino ether, polyoxyethylene soybean amino ether, polyoxyethylene beef tallow amino ether; Alkylamides such as reoxyethylene lauric acid amide, polyoxyethylene stearic acid amide, polyoxyethylene oleic acid amide; vegetable oil ethers such as polyoxyethylene castor oil ether, polyoxyethylene rapeseed oil ether; lauric acid diethanolamide, Alkanolamides such as stearic acid diethanolamide and oleic acid diethanolamide; sorbitan esters such as polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmiate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan monooleate Ethers; and the like.

  The content of the surfactant in each dispersion may be a level that does not inhibit the present invention, generally a small amount, specifically, a range of about 0.01 to 10% by mass is desirable. More preferably, it is the range of 0.05 to 5 mass%, More preferably, it is the range of about 0.1 to 2 mass%. When the content of the surfactant is less than 0.01% by mass, each dispersion such as a resin particle dispersion, a colorant dispersion, and a release agent dispersion becomes unstable, which causes aggregation. Since the stability between the particles is different at the time of agglomeration, problems such as the release of specific particles may occur. On the other hand, if the surfactant content exceeds 10% by mass, the particle size distribution of the particles may become wide, and the particle size may be difficult to control. In general, a suspension polymerization toner dispersion having a large particle size is stable even if the amount of the surfactant used is small.

-Aggregation process (aggregated particle formation process)-
In the aggregation process, the resin particle dispersion adjusted in the resin particle dispersion adjustment process and, if necessary, the above-mentioned other dispersion are mixed to form a mixed liquid, and heated at a temperature not higher than the glass transition temperature of the polyester resin for aggregation. To form aggregated particles. Aggregated particles are formed by making the pH of the mixed solution acidic while stirring. As pH, the range of 2-7 is desirable, The range of 2.2-6 is more desirable, The range of 2.4-5 is further more desirable.

  It is also effective to use a flocculant when forming the agglomerated particles. As the aggregating agent, a surfactant having a polarity opposite to that of the surfactant used for the dispersant, an inorganic metal salt, and a divalent or higher metal complex can be suitably used. In particular, the use of a metal complex is particularly desirable because the amount of the surfactant used can be reduced and the charging characteristics are improved.

  Examples of the inorganic metal salt include metal salts such as calcium chloride, calcium nitrate, barium chloride, magnesium chloride, zinc chloride, aluminum chloride, and aluminum sulfate, and polyaluminum chloride, polyaluminum hydroxide, and calcium polysulfide. Examples thereof include inorganic metal salt polymers. Of these, aluminum salts and polymers thereof are particularly preferred. In order to obtain a sharper particle size distribution, the valence of the inorganic metal salt is bivalent than monovalent, trivalent than bivalent, trivalent than trivalent, and tetravalent than trivalent. The inorganic metal salt polymer is more suitable.

  Further, when the aggregated particles have a desired particle size, a toner having a structure in which the surface of the core aggregated particles is coated with a binder resin may be prepared by additionally adding resin emulsified particles. In this case, the release agent and the polyester resin are difficult to be exposed on the toner surface, which is desirable from the viewpoints of chargeability and storage stability. In the case of additional addition, a flocculant may be added before additional addition, and pH adjustment may be performed.

-Fusion process (toner particle formation process)-
In the fusing step, the agglomeration is stopped by raising the pH of the suspension of the agglomerated particles to a range of 4 to 8 under the stirring conditions in accordance with the agglomeration step, and the glass transition temperature of the binder resin or higher. The aggregated particles are fused by heating at a temperature of. An aqueous NaOH solution is preferred as the alkaline solution used to raise the pH. In addition, since a divalent alkaline solution such as Ca (OH) ₂ is difficult to dissolve in water, the amount of addition increases or the ability to stop aggregation may not be sufficient.

  The heating time may be as long as the fusion is performed, and is preferably 0.5 hours or more and 10 hours or less. Cooling is performed after the aggregated particles are fused to obtain fused particles (toner particles). Also, in the cooling process, the cooling rate is increased in the vicinity of the melting point of the mold release agent and polyester resin (melting point ± 10 ° C range), so-called rapid cooling suppresses recrystallization of the mold release agent and polyester resin. Exposure may be suppressed.

  Through the above steps, toner particles can be obtained as fused particles. The fused particles (toner particles) obtained by fusing need to be washed through a solid-liquid separation process such as filtration as described later.

-Washing process-
The step of washing the toner particles includes a step of washing the toner particles with a treatment liquid having a pH of 9 or more and a pH of 10 or less, a step of washing the toner particles with an ion exchange resin while treating with ultrasonic waves after the pH of the toner particles is lowered to 4 or less, It is preferable to include a step of washing the toner particles with ion exchange water.
Hereinafter, the toner cleaning step will be described by dividing it into the above steps.

[Step of washing with treatment liquid of pH 9 or more and pH 10 or less]
First, the toner particles obtained in the fusing step are washed with a treatment liquid having a pH of 9 or more and pH 10 or less. Specifically, the toner particles are dispersed in ion-exchanged water, adjusted to pH 9 to 10 at a temperature of 20 ° C. or higher and 40 ° C. or lower, and washed with stirring.
If the temperature is 20 ° C. or higher, the detergency does not deteriorate. If the temperature is 40 ° C. or lower, the toner surface can be prevented from being rough. If the pH is 9 or more, the carboxylic acid is sufficiently dissociated and the adsorbed surfactant can be removed. In addition, it is more preferable to use an aluminum-based flocculant because it is easy to remove the bound surfactant due to a change in aluminum ions. A pH of 10 or less is preferable because hydrolysis hardly occurs.

  Next, the toner particles and the liquid are solid-liquid separated from the toner particle dispersion. Thereafter, the toner particles are further dispersed in ion-exchanged water at 30 ° C. and stirred with a mechanical stirrer. The step of re-dispersing in water after the solid-liquid separation and stirring is repeated until the conductivity in the toner particle dispersion becomes 100 μS or less.

[Step of washing with ion exchange resin while treating with ultrasonic waves after adjusting to pH 4 or lower]
Thereafter, in order to wash the toner particles with a treatment liquid having a pH of 4 or less, the toner particle dispersion is adjusted to a pH of 4 or less and stirred with a mechanical stirrer.
Adjusting the toner particle dispersion to pH 4 or lower suppresses dissociation of carboxylic acid, and removes surfactants bound to metal ions bound to carboxylic acid, particularly ammonium ions and ions derived from aggregating agents. can do. Thereafter, ultrasonic waves are applied to the dispersion, and the ion exchange resin is added while dispersing.
When the dissociation of the carboxylic acid is suppressed, the dispersion stability of the particles in water is reduced and the particles are aggregated. Therefore, the aggregated particles are preferably crushed using ultrasonic waves. When the agglomerated particles are not crushed, the inside of the agglomerated particles may not be sufficiently washed, and the chargeability may become non-uniform. This operation may be repeated as necessary. Further, since the ions near the surface of the toner particles are also precipitated in the water by the ultrasonic wave, the cleaning effect is further improved. Furthermore, by adding an ion exchange resin in such a state, ammonium ions can be efficiently removed.

The ultrasonic condition is preferably 28 kHz or more and 100 kHz or less, and more preferably 35 kHz or more and 80 kHz or less. If it is less than 28 kHz, sufficient crushing / cleaning effect may not be obtained, and if it is more than 100 kHz, the toner particles may be destroyed. The ultrasonic time is preferably 3 minutes to 60 minutes, more preferably 5 minutes to 45 minutes. If the time is less than 3 minutes, sufficient crushing / cleaning effects may not be obtained. If the time is longer than 60 minutes, the toner particles may be destroyed.
As the ion exchange resin, a cation exchange resin capable of substituting ammonium ions is preferable. As the ion exchange resin, known resins can be used. The addition amount of the ion exchange resin is preferably 3 to 20 parts by mass with respect to 100 parts by mass of the toner.

[Step of washing with ion exchange water]
Next, the toner that has undergone the above-described [step of washing with ion exchange resin while being treated with ultrasonic waves after being adjusted to pH 4 or lower] is subjected to solid-liquid separation. The operation of dispersing the toner in 30 ° C. ion-exchanged water, stirring with a mechanical stirrer, and solid-liquid separation is repeated.

  [Step of washing with a treatment solution of pH 9 or more and pH 10 or less], [Step of washing with ion exchange resin while treating with ultrasonic waves after adjusting to pH 4 or less] and [Step of washing with ion exchange water] The cleaning is performed through a series of three steps or by repeating the three series of steps. In addition, each step may be performed a plurality of times, for example, after [step of washing with a treatment liquid having a pH of 9 or more and pH 10 or less] is performed a plurality of times, and after the pH is adjusted to 4 or less, the ions are treated with ultrasonic waves. The step of washing with an exchange resin] and the step of washing with ion-exchanged water may be performed, or the step of washing with a treatment solution having a pH of 9 or more and pH 10 or less, and the pH is adjusted to 4 or less, followed by ultrasonic treatment. However, after performing the step of washing with an ion exchange resin, the step of washing with ion exchange water may be performed a plurality of times.

  After the toner cleaning, the solid-liquid separated toner is dried with a freeze vacuum dryer, a shelf dryer, a hot air dryer or the like. The moisture content of the toner after drying is preferably 1.2% by mass or less, and more preferably 1.0% by mass or less.

<Developer for developing electrostatic image>
The toner for developing an electrostatic charge image in this embodiment is used as it is as a one-component developer or as a two-component developer. When used as a two-component developer, it is used by mixing with a carrier.

  There is no restriction | limiting in particular as a carrier which can be used for a two-component developer, A well-known carrier can be used. Examples thereof include magnetic metals such as iron oxide, nickel and cobalt, magnetic oxides such as ferrite and magnetite, resin-coated carriers having a resin coating layer on the surface of the core material, and magnetic dispersion carriers. Further, a resin-dispersed carrier in which a conductive material or the like is dispersed in a matrix resin may be used.

  Coating resins and matrix resins used for carriers include polyethylene, polypropylene, polystyrene, polyvinyl acetate, polyvinyl alcohol, polyvinyl butyral, polyvinyl chloride, polyvinyl ether, polyvinyl ketone, vinyl chloride-vinyl acetate copolymer, styrene-acrylic. Examples thereof include, but are not limited to, acid copolymers, straight silicone resins composed of organosiloxane bonds or modified products thereof, fluororesins, polyesters, polycarbonates, phenol resins, epoxy resins and the like.

  Examples of the conductive material include metals such as gold, silver and copper, carbon black, titanium oxide, zinc oxide, barium sulfate, aluminum borate, potassium titanate, tin oxide, and carbon black. It is not limited.

  Examples of the core material of the carrier include magnetic metals such as iron, nickel, and cobalt, magnetic oxides such as ferrite and magnetite, and glass beads. However, in order to use the carrier for the magnetic brush method, it is a magnetic material. It is preferable. The volume average particle size of the core material of the carrier is generally in the range of 10 μm to 500 μm, and preferably in the range of 30 μm to 100 μm.

  In order to coat the surface of the core material of the carrier with a resin, there may be mentioned a method of coating with a coating layer forming solution prepared by dissolving the coating resin and, if necessary, various additives in an appropriate solvent. The solvent is not particularly limited and may be appropriately selected in consideration of the coating resin to be used, coating suitability, and the like.

  Specific resin coating methods include an immersion method in which the carrier core material is immersed in the coating layer forming solution, a spray method in which the coating layer forming solution is sprayed onto the surface of the carrier core material, and the carrier core material is fluidized air. A fluidized bed method in which the coating layer forming solution is sprayed in a state of being suspended by the above, a kneader coater method in which the carrier core material and the coating layer forming solution are mixed in a kneader coater, and the solvent is removed.

  The mixing ratio (mass ratio) of the toner of this embodiment and the carrier in the two-component developer is in the range of toner: carrier = 1: 100 or more and 30: 100 or less, and 3: 100 or more and 20: 100. The following range is more preferable.

<Image forming apparatus>
Next, an image forming apparatus according to an embodiment using the electrostatic image developing toner according to the embodiment will be described.
The image forming apparatus according to the embodiment forms an electrostatic latent image on the surface of the electrostatic latent image holding member, charging means for charging the surface of the electrostatic latent image holding member by discharging, and electrostatic latent image holding member. Electrostatic latent image forming means, developing means for developing the electrostatic latent image into a toner image with a developer, transfer means for transferring the toner image on the surface of the electrostatic latent image holding member to the surface of the transfer target, A fixing unit that heats and fixes the toner image transferred to the transfer body, and uses the electrostatic charge image developer according to the embodiment as the developer.

In this image forming apparatus, for example, the part including the developing unit may have a cartridge structure (process cartridge) that can be attached to and detached from the image forming apparatus main body. As the process cartridge, a developer holding body is used. The process cartridge according to the embodiment that includes at least the electrostatic image developer according to the embodiment is preferably used.
Hereinafter, an example of an image forming apparatus according to an embodiment will be described as an embodiment, but the present invention is not limited to this. The main parts shown in the figure will be described, and the description of the other parts will be omitted.

  FIG. 1 is a schematic diagram showing a quadruple tandem full-color image forming apparatus. The image forming apparatus shown in FIG. 1 is the first of the electrophotographic systems that outputs yellow (Y), magenta (M), cyan (C), and black (K) images based on color-separated image data. Fourth image forming units 10Y, 10M, 10C, and 10K (image forming means) are provided. These image forming units (hereinafter sometimes simply referred to as “units”) 10Y, 10M, 10C, and 10K are juxtaposed at a predetermined distance in the horizontal direction. The units 10Y, 10M, 10C, and 10K may be process cartridges that are detachable from the main body of the image forming apparatus.

Above each of the units 10Y, 10M, 10C, and 10K, an intermediate transfer belt 20 as an intermediate transfer member is extended through each unit. The intermediate transfer belt 20 is provided by being wound around a driving roller 22 and a support roller 24 that are in contact with the inner surface of the intermediate transfer belt 20 that are spaced apart from each other from the left to the right in the drawing. The vehicle travels in the direction toward the unit 10K. A force is applied to the support roller 24 in a direction away from the driving roller 22 by a spring or the like (not shown), and a predetermined tension is applied to the intermediate transfer belt 20 wound around the both. Further, an intermediate transfer member cleaning device 30 is provided on the side of the image carrier of the intermediate transfer belt 20 so as to face the driving roller 22.
Further, each of the developing devices (developing means) 4Y, 4M, 4C, and 4K of the units 10Y, 10M, 10C, and 10K has yellow, magenta, cyan, and black contained in the toner cartridges 8Y, 8M, 8C, and 8K. The four color toners can be supplied.

  Since the first to fourth units 10Y, 10M, 10C, and 10K described above have the same configuration, here, the first image that forms the yellow image disposed on the upstream side in the intermediate transfer belt traveling direction is formed. The unit 10Y will be described as a representative. In addition, by assigning reference numerals with magenta (M), cyan (C), and black (K) instead of yellow (Y) to parts equivalent to the first unit 10Y, the second to fourth Description of the units 10M, 10C, and 10K will be omitted.

  The first unit 10Y includes a photoreceptor 1Y that functions as an image holding member. Around the photoreceptor 1Y, a scorotron charger 2Y for charging the surface of the photoreceptor 1Y to a predetermined potential, and the charged surface is exposed by a laser beam 3Y based on the color-separated image signal, thereby forming an electrostatic image. A developing device (developing means) 4Y for developing the electrostatic image by supplying toner charged to the electrostatic image, and a primary transfer roller 5Y for transferring the developed toner image onto the intermediate transfer belt 20 A (primary transfer unit) and a photoconductor cleaning device (cleaning unit) 6Y for removing toner remaining on the surface of the photoconductor 1Y after the primary transfer are sequentially arranged.

  The primary transfer roller 5Y is disposed inside the intermediate transfer belt 20, and is provided at a position facing the photoreceptor 1Y. Further, a bias power source (not shown) for applying a primary transfer bias is connected to each of the primary transfer rollers 5Y, 5M, 5C, and 5K. Each bias power source varies the transfer bias applied to each primary transfer roller under the control of a control unit (not shown).

Hereinafter, an operation of forming a yellow image in the first unit 10Y will be described. First, prior to operation, the surface of the photoreceptor 1Y is charged to a potential of about −600V to −800V by a scorotron charger 2Y that performs charging by corona discharge generated by applying a high voltage to the tungsten wire. .
The photoreceptor 1Y is formed by laminating a photosensitive layer on a conductive substrate (volume resistivity at 20 ° C .: 1 × 10 ⁻⁶ Ωcm or less). This photosensitive layer usually has a high resistance (a resistance equivalent to that of a general resin), but has a property that the specific resistance of the portion irradiated with the laser beam changes when irradiated with the laser beam 3Y. Therefore, a laser beam 3Y is output to the surface of the charged photoreceptor 1Y via the exposure device 3 in accordance with yellow image data sent from a control unit (not shown). The laser beam 3Y is applied to the photosensitive layer on the surface of the photoreceptor 1Y, whereby an electrostatic latent image of a yellow print pattern is formed on the surface of the photoreceptor 1Y.

The electrostatic charge image is an image formed on the surface of the photoreceptor 1Y by charging, and the specific resistance of the irradiated portion of the photosensitive layer is lowered by the laser beam 3Y, and the charged charge on the surface of the photoreceptor 1Y flows. On the other hand, this is a so-called negative latent image formed by the charge remaining in the portion not irradiated with the laser beam 3Y.
The electrostatic image formed on the photoreceptor 1Y in this way is rotated to a predetermined development position as the photoreceptor 1Y travels. At this development position, the electrostatic charge image on the photoreceptor 1Y is visualized (developed image) by the developing device 4Y.

  In the developing device 4Y, for example, yellow toner having a volume average particle diameter of 7 μm including at least a yellow colorant, a crystalline resin, and an amorphous resin is contained. The yellow toner is triboelectrically charged by being agitated inside the developing device 4Y, and has a charge of the same polarity (negative polarity) as the charged charge on the photoreceptor 1Y, and a developer roll (developer holder). Is held on. As the surface of the photoreceptor 1Y passes through the developing device 4Y, the yellow toner is electrostatically attached to the latent image portion on the surface of the photoreceptor 1Y, and the latent image is developed with the yellow toner. . The photoreceptor 1Y on which the yellow toner image is formed continues to run at a predetermined speed, and the toner image developed on the photoreceptor 1Y is conveyed to a predetermined primary transfer position.

When the yellow toner image on the photoreceptor 1Y is conveyed to the primary transfer, a predetermined primary transfer bias is applied to the primary transfer roller 5Y, and the electrostatic force directed from the photoreceptor 1Y to the primary transfer roller 5Y generates a toner image. The toner image on the photoreceptor 1 </ b> Y is transferred onto the intermediate transfer belt 20. The transfer bias applied at this time is a (+) polarity opposite to the polarity (−) of the toner, and is controlled to about +10 μA by the control unit (not shown) in the first unit 10Y, for example.
On the other hand, the toner remaining on the photoreceptor 1Y is removed and collected by the cleaning device 6Y.

Further, the primary transfer bias applied to the primary transfer rollers 5M, 5C, and 5K after the second unit 10M is also controlled according to the first unit.
Thus, the intermediate transfer belt 20 onto which the yellow toner image has been transferred by the first unit 10Y is sequentially conveyed through the second to fourth units 10M, 10C, and 10K, and the toner images of the respective colors are superimposed and transferred in a multiple manner. The

  The intermediate transfer belt 20 onto which the four color toner images have been transferred through the first to fourth units is arranged on the image transfer surface side of the intermediate transfer belt 20 and the support roller 24 in contact with the inner surface of the intermediate transfer belt 20. The secondary transfer roller (secondary transfer means) 26 is connected to a secondary transfer portion. On the other hand, the recording paper (transfer object) P is fed at a predetermined timing into a gap where the secondary transfer roller 26 and the intermediate transfer belt 20 are pressed against each other via a supply mechanism, and a predetermined secondary transfer bias is supported. Applied to the roller 24. The transfer bias applied at this time is a (−) polarity that is the same polarity as the polarity (−) of the toner, and an electrostatic force from the intermediate transfer belt 20 toward the recording paper P is applied to the toner image, and the transfer bias is applied to the intermediate transfer belt 20. The toner image is transferred onto the recording paper P. Note that the secondary transfer bias at this time is determined according to the resistance detected by a resistance detecting means (not shown) for detecting the resistance of the secondary transfer portion, and is voltage-controlled.

  Thereafter, the recording paper P is sent to a heating type fixing device (fixing means) 28, where the toner image is heated, and the color-superposed toner image is melted and fixed on the recording paper P.

Examples of the transfer target to which the toner image is transferred include plain paper and OHP sheet used for electrophotographic copying machines, printers, and the like.
In order to further improve the smoothness of the image surface after fixing, it is preferable that the surface of the transfer target is as smooth as possible. For example, coated paper in which the surface of plain paper is coated with a resin or the like, for printing Art paper or the like can be suitably used.

  Further, it is preferable that the image glossiness (75 °) after fixing of a monochrome image composed of cyan, magenta, and yellow having an image area ratio of 100% is 50% or more. In a full-color image, it is desirable that the image gloss is high from the viewpoint of color development and photographic image quality reproducibility. When using highly glossy paper such as coated paper for higher image quality, if the image gloss is significantly lower than the gloss of the paper, it will appear visually dark, so the fixed image will be less than the gloss of the paper. High gloss is more preferable. For example, when fixing is performed using coated paper such as coated paper having a glossiness (75 °) of 50% or more, the image glossiness after fixing is desirably 50% or more, and more desirably 60% or more. The measurement can be performed based on JIS Z 8741.

The recording paper P on which the color image has been fixed is carried out toward the discharge unit, and a series of color image forming operations is completed.
The image forming apparatus exemplified above is configured to transfer the toner image onto the recording paper P via the intermediate transfer belt 20, but the present invention is not limited to this configuration, and the toner image is directly transferred from the photoconductor. It may be a structure that is transferred to a recording sheet.

  The image forming apparatus according to the present embodiment uses the scorotron type chargers 2Y, 2M, 2C, and 2K. However, the present invention is not limited to this configuration, and other systems that perform charging by discharging, such as the corotron system. The structure using the charger may be used.

Next, the fixing device 28 of this embodiment will be described in detail. The fixing device 28 of this embodiment includes a heating roll and a pressure roll.
The heating roll has a cylindrical core, an elastic layer formed on the surface of the core, and a release layer formed on the surface of the elastic layer, and includes a heating source inside the core. An adhesive layer is provided between the elastic layer and the release layer. Moreover, the side surface of the heating roll is cut, and the elastic layer and the adhesive layer are exposed.

Examples of the material of the core include metals such as aluminum, stainless steel (SUS), iron, and copper, alloys, fiber reinforced metal (FRM), and ceramics.
Examples of the material for the elastic layer include silicone rubber and fluororubber.
Examples of the material for the release layer include fluororubber, silicone rubber, fluororesin, and the like, and fluororesin is preferred from the standpoint of releasability.
Examples of the material for the adhesive layer include primers mainly composed of polyamide, polyimide, polyamideimide, polyarylene sulfide, and the like, and silicone modified primers.

The pressure belt has a base material and a release layer.
Examples of the material for the base material include thermosetting polyimide, thermoplastic polyimide, polyamide, polyamideimide, polybenzimidazole, and the like. In the base material, functional fillers such as inorganic particles, metal powders, metal oxides, and organic metal oxides can be appropriately added depending on the purposes such as conductivity, thermal conductivity, insulation, and reinforcement. .
Examples of the release layer include a fluororesin.

In the present embodiment, since the fixing device having the above-described configuration is used, water vapor generated from, for example, the recording paper P contacts the adhesive layer exposed on the side surface of the heating roll and deteriorates due to heating during fixing. May end up. In particular, when the recording paper P is acidic paper, deterioration is accelerated by water vapor containing an acidic component. However, in this embodiment, since the toner having the above-described configuration is used, the acid is neutralized by ammonia released from the toner by heating at the time of fixing, so that the acid comes into contact with the adhesive layer exposed on the side surface of the heating roll. Deterioration is suppressed.
In the present embodiment, the fixing device 28 having the above-described configuration is used. However, the fixing device is not limited to the above-described configuration as long as the fixing device is a heat fixing type.

<Process cartridge, toner cartridge>
FIG. 2 is a schematic configuration diagram showing an example of a preferred example of a process cartridge for containing an electrostatic charge image developer according to the embodiment. In the process cartridge 200, a charger 108, a developing device 111, a photoconductor cleaning device 113, an opening 118 for exposure, and an opening 117 for static elimination exposure are combined using a mounting rail 116 together with the photoconductor 107. , And integrated.
The process cartridge 200 is detachable from an image forming apparatus main body including a transfer device 112 that transfers an image onto the recording paper 300, a fixing device 115, and other components not shown. The image forming apparatus is configured together with the image forming apparatus main body.

  The process cartridge 200 shown in FIG. 2 includes a charger 108, a developing device 111, a cleaning device 113, an opening 118 for exposure, and an opening 117 for static elimination exposure. These devices are optional. Can be combined. In the process cartridge of this embodiment, in addition to the photoconductor 107, a charger 108, a developing device 111, a cleaning device (cleaning means) 113, an opening 118 for exposure, and an opening 117 for discharge exposure. At least one selected from the group consisting of:

  Next, the toner cartridge according to the embodiment will be described. The toner cartridge according to the embodiment is detachably attached to the image forming apparatus, and at least the toner cartridge that stores toner to be supplied to the developing unit provided in the image forming apparatus is described above. It is a toner according to the embodiment. Note that the toner cartridge according to the embodiment only needs to contain at least toner, and may contain developer, for example, depending on the mechanism of the image forming apparatus.

  Therefore, in the image forming apparatus having a configuration in which the toner cartridge can be attached and detached, the storability is maintained even in the toner cartridge whose container is miniaturized by using the toner cartridge containing the toner according to the embodiment. This makes it possible to achieve low-temperature fixing while maintaining high image quality.

  The image forming apparatus shown in FIG. 1 is an image forming apparatus having a configuration in which the toner cartridges 8Y, 8M, 8C, and 8K can be attached and detached, and the developing devices 4Y, 4M, 4C, and 4K are respectively the developing devices ( And a toner supply pipe (not shown). Further, when the amount of toner stored in the toner cartridge is low, the toner cartridge can be replaced.

  EXAMPLES Hereinafter, although an Example and a comparative example are given and embodiment is described in detail in detail, this invention is not limited to a following example. Unless otherwise specified, “part” is based on mass.

[Measuring method]
<Measurement method of ammonium ion content>
Ammonium ions in the toner are dispersed by dispersing the toner in water, performing ultrasonic dispersion at a temperature equal to or higher than the glass transition temperature of the resin contained in the toner, extracting ammonia into the water, and analyzing by ion chromatography. Find the amount. Further, when a crystalline polyester resin is contained, the dispersion is performed at a temperature equal to or higher than the melting point. The specific ammonium ion content was measured as follows.

  A toner dispersion liquid in which 0.5 g of toner and 100 ml of a dispersion containing 1.0% by weight of polyvinyl alcohol in pure water are placed in a 200 ml lidded flask is higher than the glass transition temperature of the resin contained in the toner. Dispersion was performed for 30 minutes with an ultrasonic disperser (manufactured by ASONE, model number: USD-4R, 28 kHz) under the conditions of 80 ° C. Thereafter, the filtrate obtained by suction filtration of the toner dispersion was analyzed by an ion chromatograph (Nippon Dionex, model number ICS-2000) to determine the ammonium ion content in the toner. The analysis conditions were as follows: cation separation column: IonPacCS12A manufactured by Nippon Dionex Co., Ltd., cation guard column: IonPacCG12A manufactured by Nippon Dionex Co., Ltd., eluent: methanesulfonic acid 20 mM, flow rate: 1 ml / min, temperature: 35 ° C. Detection method: Electrical conductivity method (suppressor method).

<Measurement method of ammonium ion reduction amount>
First, the toner was placed in a cylindrical container having a diameter of 10 cm so as to have a height of 10 cm, and allowed to stand at room temperature (25 ° C.) for 1 hour in a sealed state. Thereafter, the toner immediately after the container was opened was measured in the same manner as the method for measuring the ammonium ion content, and the amount of ammonium ions C _B (ppm) contained in the toner before exposure was determined.
Next, 1.0 g of the toner immediately after opening the container is uniformly spread so as to have an area of 25 cm ² and left to stand in air at a temperature of 30 ° C. and a humidity of 80% for 6 hours. Measurement similar to the measurement method was performed to determine the amount of ammonium ion C _A (ppm) contained in the toner after exposure.
Furthermore, the ammonium ion amount (ammonium ion reduction amount) C _D (ppm) reduced by exposure was determined by the following formula.
Formula: C _D (ppm) = C _B (ppm) −C _A (ppm)

<Measurement of acid value>
The acid value was measured according to JIS K0070 and using a neutralization titration method. That is, take an appropriate amount of sample, add 100 ml of solvent (diethyl ether / ethanol mixture) and a few drops of indicator (phenolphthalein solution), and shake well until the sample is completely dissolved in a water bath. This was titrated with a 0.1 mol / l potassium hydroxide ethanol solution, and the end point was when the indicator was light red for 30 seconds. When the acid value is A, the sample amount is S (g), the 0.1 mol / l potassium hydroxide ethanol solution used for the titration is B (ml), and f is the factor of the 0.1 mol / l potassium hydroxide ethanol solution. , A = (B × f × 5.611) / S.

<Measuring method of crystalline polyester resin content in polyester resin>
First, the crystalline resin and the amorphous resin in the toner are separated. First, the toner is allowed to stand for 24 hours in a constant temperature bath at a temperature of 50 ° C. and a humidity of 55 RH% to cancel the thermal history of the toner. Thereafter, 10 g of toner is dissolved in 100 g of methyl ethyl ketone (MEK) at room temperature (20 to 25 ° C.). This is because when the toner contains a crystalline resin and an amorphous resin, almost only the amorphous resin is dissolved in MEK at room temperature. Accordingly, since the MEK-soluble component contains an amorphous resin including an amorphous polyester resin, the solution is centrifuged (centrifuge “H-18”, Kokusan Co., Ltd., 3500 rotations) after the dissolution. For 20 minutes), a non-crystalline polyester resin is obtained from the supernatant. The solid content after centrifugation is dissolved again in 100 g of MEK and centrifuged, and the supernatant is discarded. On the other hand, a crystalline polyester resin is obtained from a supernatant obtained by dissolving the solid content after centrifugation in 100 g of MEK under heating at 70 ° C. and separating the solid content by centrifugation.
From the mass ratio of the resins thus obtained, the content of the crystalline polyester resin in the polyester resin contained in the toner is determined.

<Measuring method of glass transition temperature and melting point>
The glass transition temperature and melting point were measured according to JIS 7121-1987 using a differential scanning calorimeter (manufactured by Mac Science: DSC3110, thermal analysis system 001). The melting point of a mixture of indium and zinc was used for temperature correction of the detection part of this apparatus, and the heat of fusion of indium was used for correction of heat quantity. The sample was put in an aluminum pan, an aluminum pan containing the sample and an empty aluminum pan for control were set, and the measurement was performed at a heating rate of 10 ° C./min.
About melting | fusing point, it was set as melting | fusing point with the temperature of the peak of the largest endothermic peak among the endothermic peaks of the DSC curve obtained by measurement.
Moreover, about the glass transition temperature, it was set as the glass transition temperature with the temperature of the intersection of the extended line of the base line in the endothermic part of the DSC curve obtained by the measurement, and the rising line.

<Measurement of weight average molecular weight (Mw)>
The weight average molecular weight (Mw) (polystyrene conversion) of the polyester resin was measured using GPC (Tosoh Co., Ltd .: HLC-8120 made). The column used was Tosoh TSKgel SuperHM-M (15 cm), and the GPC spectrum was measured with a THF solvent. The molecular weight of the polyester resin was calculated using a molecular weight calibration curve created with a monodisperse polystyrene standard sample.

<Calculation of average circularity>
To measure the average circularity of the toner, FPIA 3000 (manufactured by Hosokawa Micron Corporation) is used. A toner dispersion for measurement was prepared as follows. First, 30 ml of ion-exchanged water is placed in a 100 ml beaker, and 5 drops of a 20% aqueous solution of a surfactant (sodium dodecylbenzenesulfonate) is added dropwise thereto as a dispersant. 20 mg of toner was put in this liquid, and ultrasonic dispersion was performed for 3 minutes to prepare a dispersion. The average circularity was calculated by measuring this dispersion using FPIA 3000 and measuring 4,500.

<Measurement method of toner volume average particle size>
The volume average particle diameter of the toner was measured using a Coulter Multisizer II type (manufactured by Beckman-Coulter). As the electrolytic solution, ISOTON-II (manufactured by Beckman-Coulter) was used.

  As a measurement method, 0.5 mg of a measurement sample was added to 2 ml of a 5% aqueous solution of a surfactant (sodium dodecylbenzenesulfonate) as a dispersant, and this was added to 100 ml of the electrolytic solution. The electrolytic solution in which the measurement sample is suspended is subjected to a dispersion treatment with an ultrasonic disperser for about 1 minute. Using the Coulter Multisizer-II type aperture with an aperture diameter of 100 μm, the particle diameter is from 2.0. The particle size distribution of particles in the range of 60 μm was measured. The number of particles measured is 50,000.

  For the measured particle size distribution, a cumulative distribution was drawn from the smaller diameter side with respect to the divided particle size range (channel), and the particle size at 50% cumulative was defined as the volume average particle size.

<Measuring method of average particle diameter of resin particles / release agent particles / pigment particles>
Using a laser diffraction particle size distribution analyzer (LA-700: manufactured by HORIBA, Ltd.), the volume average particle diameter of resin particles, release agent particles, and pigment particles was measured.

  As a measuring method, the sample in the state of dispersion is adjusted so as to have a solid content of about 2 g, and ion exchange water is added thereto to make about 40 ml. This was put into the cell until an appropriate concentration was reached, waited for 2 minutes, and measured when the concentration in the cell became almost stable.

  The volume average particle diameter of each obtained channel was accumulated from the smaller volume average particle diameter, and the volume average particle diameter was determined to be 50%.

  When measuring powder, 2 g of a measurement sample is added to 50 ml of a 5% aqueous solution of a surfactant (sodium dodecylbenzenesulfonate), and dispersed for 2 minutes with an ultrasonic disperser (1,000 Hz). A sample was prepared and measured by the same method as the above-mentioned dispersion.

<Measurement of toner particle size distribution>
For the measurement of the particle size distribution index of the toner, a cumulative distribution is drawn from the small diameter side for each of the volume and number of the particle size range (channel) obtained by dividing the particle size distribution measured using the Coulter Multisizer-II type, Volume average particle diameter D _16V , cumulative average 16%, number average particle diameter D _16P , volume average particle diameter D _50V , cumulative 50%, number average particle diameter D _50p , volume average particle diameter D _84V , cumulative 84%, The number average particle diameter D is defined as _84p . Using these, the volume average particle size distribution index (GSD _v ) is determined from (D _84V / D _16V ) 0.5, and the number average particle size distribution index (GSD _p ) is _calculated from (D _84p / D _16p ) 0.5. The lower number average particle size distribution index (below GSD _p ) was calculated from (D _16P / D _50P ).

<Method of measuring the amount of ammonium ions contained in the toner surface and inside the toner>
Here, the amount of ammonium ions contained in the toner surface is measured as follows. Specifically, a toner dispersion in which 0.5 g of toner and 100 ml of a dispersion containing 1.0% by weight of polyvinyl alcohol in pure water are placed in a 200 ml flask with a lid is a glass of resin contained in the toner. Dispersion is performed for 15 minutes with an ultrasonic disperser under the condition of 25 ° C., which is a temperature sufficiently lower than the transition temperature. Thereafter, the measurement is performed in the same manner as in the method for measuring the amount of ammonium ions described above.
Further, the amount of ammonium ions contained in the toner is a value obtained by subtracting the amount of ammonium ions contained in the toner surface from the amount of ammonium ions obtained by the above-described method for measuring the amount of ammonium ions.

[Synthesis of polyester resin]
<Synthesis of Amorphous Polyester Resin (1)>
In a heat-dried two-necked flask, 80 mol parts of polyoxypropylene (2,2) -2,2-bis (4-hydroxyphenyl) propane, 10 mol parts of ethylene glycol, 10 mol parts of cyclohexanediol, and terephthalic acid After 80 parts by mole, 10 parts by mole of isophthalic acid, and 10 parts by mole of n-dodecenyl succinic acid, dibutyltin oxide is added as a catalyst, nitrogen gas is introduced into the container, and the temperature is raised in an inert atmosphere. A copolycondensation reaction was carried out at 150 to 230 ° C. for about 12 hours, and then the pressure was gradually reduced at 210 to 250 ° C. to synthesize an amorphous polyester resin (1).

  The weight average molecular weight (Mw) of the obtained amorphous polyester resin (1) was 17,200. The acid value of the amorphous polyester resin (1) was 12.4 mgKOH / g.

Furthermore, the glass transition temperature of the non-crystalline polyester resin (1) was measured using a differential scanning calorimeter (DSC), and analyzed according to JIS standards (see JIS K-7121).
As a result, a stepwise endothermic change was observed without showing a clear peak. The glass transition temperature (Tg) at the midpoint of the stepwise endothermic change was 59 ° C.

<Synthesis of Amorphous Polyester Resin (2)>
In a heat-dried two-necked flask, 90 mol parts of polyoxyethylene (2,0) -2,2-bis (4-hydroxyphenyl) propane, 10 mol parts of ethylene glycol, 80 mol parts of terephthalic acid, and isophthalic acid An amorphous polyester resin (2) was synthesized in the same manner as the amorphous polyester resin (1) except that 20 mol parts were used as a raw material.

When the molecular weight was measured in the same manner as in the amorphous polyester resin (1), the weight average molecular weight (Mw) of the obtained amorphous polyester resin (2) was 16,200.
The acid value of the amorphous polyester resin (2) was 18.2 mgKOH / g.

  When the glass transition temperature was measured in the same manner as the non-crystalline polyester resin (1) and the DSC spectrum was obtained, no clear peak was shown, and a stepwise endothermic change was observed. The glass transition temperature (Tg) at the midpoint of the stepwise endothermic change was 62 ° C.

<Synthesis of Amorphous Polyester Resin (3)>
At the end of the reaction of the amorphous polyester resin (1), 2.6 mol parts of dimethyl terephthalate was added to modify the terminal of the resin, thereby synthesizing the amorphous polyester resin (3).

When the molecular weight was measured in the same manner as in the amorphous polyester resin (1), the weight average molecular weight (Mw) of the obtained amorphous polyester resin (3) was 18,400.
The acid value of the amorphous polyester resin (3) was 2.2 mgKOH / g.

  When the glass transition temperature was measured in the same manner as the non-crystalline polyester resin (1) and the DSC spectrum was obtained, no clear peak was shown, and a stepwise endothermic change was observed. The glass transition temperature (Tg) at the midpoint of the stepwise endothermic change was 60 ° C.

<Synthesis of Amorphous Polyester Resin (4)>
At the end of the reaction of the amorphous polyester resin (1), 2.6 mol parts of 1,2,4 trimellitic acid was added to modify the terminal of the resin to synthesize the amorphous polyester resin (4).

When the molecular weight was measured in the same manner as in the amorphous polyester resin (1), the weight average molecular weight (Mw) of the obtained amorphous polyester resin (4) was 20,400.
The acid value of the amorphous polyester resin (4) was 32.4 mgKOH / g.

  When the glass transition temperature was measured in the same manner as the non-crystalline polyester resin (1) and the DSC spectrum was obtained, no clear peak was shown, and a stepwise endothermic change was observed. The glass transition temperature (Tg) at the midpoint of the stepwise endothermic change was 62 ° C.

<Synthesis of crystalline polyester resin (1)>
In a heat-dried three-necked flask, 43.4 parts by mass of dimethyl sebacate, 32.8 parts by mass of 1,10-decanediol, 27 parts by mass of dimethyl sulfoxide, 0.03 parts by mass of dibutyltin oxide as a catalyst, Then, the air in the container was brought into an inert atmosphere with nitrogen gas by depressurization, and stirred at 180 ° C. for 4 hours with mechanical stirring. Dimethyl sulfoxide was distilled off under reduced pressure, and then the temperature was gradually raised to 220 ° C. under reduced pressure, stirred for 1.5 hours, air-cooled when it became viscous, the reaction was stopped, and aliphatic 65 parts by mass of a crystalline polyester resin (1) was synthesized.

When the molecular weight was measured in the same manner as for the amorphous polyester resin (1), the resulting aliphatic crystalline polyester resin (1) had a weight average molecular weight (Mw) of 15,400.
Further, the melting point measurement was performed in the same manner as the non-crystalline polyester resin (1), and the DSC spectrum was obtained. As a result, the aliphatic crystalline polyester resin (1) had a clear peak, and the melting point (Tm1) was 76 ° C. Met.

  Table 1 below shows the weight average molecular weight (Mw), glass transition temperature or melting point, and acid value of the non-crystalline polyester resin and the crystalline polyester resin.

[Dispersion adjustment]
<Preparation of amorphous polyester resin dispersion (A1)>
-Amorphous polyester resin (1) 100 parts by mass-70 parts by mass of ethyl acetate-15 parts by mass of isopropyl alcohol

  A mixed solvent of the ethyl acetate and the isopropyl alcohol was added to a 5 L separable flask, and the resin was gradually added thereto, and the mixture was stirred with a three-one motor and completely dissolved to obtain an oil phase.

  To this stirred oil phase, a 10% by mass aqueous ammonia solution is gradually added dropwise with a dropper so that the total amount becomes 3 parts by mass, and further 230 parts by mass of ion-exchanged water is gradually added dropwise at a rate of 10 ml / min. Phase-emulsification was performed, and the solvent was removed while the pressure was reduced with an evaporator to obtain “amorphous polyester resin dispersion (A1)” containing “amorphous polyester resin (1)”. The volume average particle diameter of the resin particles dispersed in this dispersion was 182 nm. The resin particle concentration of the dispersion was adjusted to 20% by mass with ion exchange water.

<Preparation of Amorphous Polyester Resin Dispersion (A2)>
The non-crystalline polyester resin dispersion (A2) was prepared in the same manner as the non-crystalline polyester resin dispersion (A1) except that the non-crystalline polyester resin (2) was used instead of the non-crystalline polyester resin (1). Obtained. The volume average particle diameter of the resin particles in the dispersion was 164 nm, and the resin particle concentration in the dispersion was adjusted to 20% by mass with ion-exchanged water.

<Preparation of Amorphous Polyester Resin Dispersion (A3)>
An amorphous polyester resin dispersion (A3) was obtained in the same manner as the amorphous polyester resin dispersion (A2) except that the total amount of 10% by mass aqueous ammonia used was 5 parts by mass. The volume average particle diameter of the resin particles in the dispersion was 170 nm, and the resin particle concentration in the dispersion was adjusted to 20% by mass with ion-exchanged water.

<Preparation of amorphous polyester resin dispersion (B1)>
Similar to the non-crystalline polyester resin dispersion (A1) except that non-crystalline polyester resin (3) is used instead of non-crystalline polyester resin (1) and the 10 mass% aqueous ammonia solution is made 1 part by mass in total. Thus, an amorphous polyester resin dispersion (B1) was obtained. The volume average particle diameter of the resin particles in the dispersion was 265 nm, the particle size distribution was broad, and coarse powder was present. The resin particle concentration of the dispersion was adjusted to 20% by mass with ion exchange water.

<Preparation of non-crystalline polyester resin dispersion (B2)>
The non-crystalline polyester resin dispersion (B2) was prepared in the same manner as the non-crystalline polyester resin dispersion (A1) except that the non-crystalline polyester resin (4) was used instead of the non-crystalline polyester resin (1). Obtained. The volume average particle diameter of the resin particles in the dispersion was 215 nm, and the resin particle concentration in the dispersion was adjusted to 20% by mass with ion-exchanged water.

<Preparation of amorphous polyester resin dispersion (B3)>
An amorphous polyester resin dispersion (B3) was obtained in the same manner as the amorphous polyester resin dispersion (B2), except that the total amount of the 10% by mass ammonia aqueous solution used was 12 parts by mass. The volume average particle diameter of the resin particles in the dispersion was 154 nm, and the resin particle concentration in the dispersion was adjusted to 20% by mass with ion-exchanged water.

<Preparation of amorphous polyester resin dispersion (B4)>
-Amorphous polyester resin (1) 100 parts by mass-70 parts by mass of ethyl acetate-20 parts by mass of isopropyl alcohol

  A mixed solvent of the ethyl acetate and the isopropyl alcohol was added to a 5 L separable flask, and the resin was gradually added thereto, and the mixture was stirred with a three-one motor and completely dissolved to obtain an oil phase.

  To this stirred oil phase, 0.3N sodium hydroxide aqueous solution is gradually dropped with a dropper so that the total amount becomes 0.1 parts by mass, and further 230 parts by mass of ion-exchanged water is gradually added at a rate of 10 ml / min. The solution was added dropwise to cause phase inversion emulsification, and solvent removal was performed while reducing the pressure with an evaporator to obtain “amorphous polyester resin dispersion (B4)” containing “amorphous polyester resin (1)”. The volume average particle diameter of the resin particles dispersed in this dispersion was 200 nm. The resin particle concentration of the dispersion was adjusted to 20% by mass with ion exchange water.

<Preparation of crystalline polyester resin dispersion (A1)>
A crystalline polyester resin dispersion (A1) was obtained in the same manner as the amorphous polyester resin dispersion (A1) except that the crystalline polyester resin (1) was used instead of the amorphous polyester resin (1). . The volume average particle diameter of the resin particles in the dispersion was 165 nm, and the resin particle concentration in the dispersion was adjusted to 20% by mass with ion-exchanged water.

<Adjustment of mold release agent dispersion>
Paraffin wax (Nippon Seiwa Co., Ltd., HNP-9, melting point: 75 ° C.): 50 parts Anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd., Neogen RK): 0.5 parts Exchanged water: 200 parts or more were mixed, heated to 95 ° C., and dispersed using a homogenizer (manufactured by IKA, Ultra Turrax T50). Thereafter, a dispersion treatment (solid content concentration: 20%) in which the release agent was dispersed was prepared by dispersing with a Manton Gorin high-pressure homogenizer (Gorin). The volume average particle size of the release agent particles was 0.23 μm.

<Adjustment of colorant dispersion>
・ 1000 parts of cyan pigment (manufactured by Dainichi Seika Co., Ltd., Pigment Blue 15: 3 (copper phthalocyanine)) 15 parts of anionic surfactant (Neogen R, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) 9000 parts or more of ion-exchanged water Mix, dissolve and disperse for about 1 hour using a high-pressure impact disperser Ultimateizer (HJP30006, manufactured by Sugino Machine Co., Ltd.) to prepare a colorant dispersion in which a colorant (cyan pigment) is dispersed. did. The volume average particle size of the colorant (cyan pigment) particles in the colorant dispersion was 0.16 μm, and the solid content concentration was 20%.

[Production of toner]
<Example 1: Production of toner (1)>
・ Crystalline polyester resin dispersion (A1) 26.7 parts ・ Amorphous polyester resin dispersion (A1) 267 parts ・ Colorant dispersion 25 parts ・ Releasing agent dispersion 40 parts ・ Anionic surfactant (TeycaPower) ) 2.0 parts The above raw materials are put into a 2 L cylindrical stainless steel container, and the homogenizer is rotated at 4000 rpm using a homogenizer (manufactured by IKA, Ultra Lalux T50), and dispersed and mixed for 10 minutes while applying a shearing force. did. Next, 1.75 parts of a 10% nitric acid aqueous solution of polyaluminum chloride as a flocculant was gradually dropped, and the homogenizer was rotated at 5000 rpm for 15 minutes and mixed to obtain a raw material dispersion.

-Aggregation process-
Thereafter, the raw material dispersion was transferred to a polymerization kettle equipped with a stirrer and a thermometer and started to be heated with a mantle heater to promote the growth of aggregated particles at 42 ° C. At this time, the pH of the raw material dispersion was adjusted to a range of 3.2 or more and 3.8 or less using 0.3N nitric acid or 1N sodium hydroxide aqueous solution. The raw material dispersion was kept in the above pH range and allowed to stand for about 2 hours to form aggregated particles. The volume average particle diameter of the aggregated particles was 5.4 μm.

-Fusion process-
Next, 100 parts of the amorphous polyester resin dispersion (A1) was additionally added to the raw material dispersion, and the resin particles of the amorphous polyester resin (1) were adhered to the surface of the aggregated particles. Further, the temperature of the raw material dispersion was raised to 44 ° C., and aggregated particles were prepared while confirming the size and form of the particles using an optical microscope and Multisizer II. Thereafter, in order to fuse the aggregated particles, an aqueous NaOH solution was added dropwise to the raw material dispersion to adjust the pH to 7.5, and then the raw material dispersion was heated to 95 ° C. Thereafter, the raw material dispersion was allowed to stand for 3 hours to fuse the aggregated particles. After confirming that the aggregated particles were fused with an optical microscope, the raw material dispersion was cooled at a temperature decrease rate of 1.0 ° C./min.

-Washing process-
[Step of washing with treatment liquid of pH 9 or more and pH 10 or less]
Thereafter, using 0.3N nitric acid or 1N aqueous sodium hydroxide solution, the raw material dispersion was adjusted to pH 9.5 at 25 ° C., stirred for 20 minutes, and sieved with a mesh having a pore diameter of 20 μm. Next, the raw material dispersion was filtered. The toner after the solid-liquid separation was dispersed in ion-exchanged water at 30 ° C., which is 20 times the amount of the solid content of the toner, and stirred for 20 minutes for filtration.
This process was repeated three times and it was confirmed that the filtrate had a conductivity of 34 μS.

[Step of washing with ion exchange resin while treating with ultrasonic waves after adjusting to pH 4 or lower]
Thereafter, the toner is redispersed in ion exchange water at 30 ° C., which is 20 times the solid amount of the toner, and 5 parts by mass of ion exchange resin is added to 100 parts by mass of the toner. Washing was performed for 10 minutes while applying a frequency of 45 kHz using an electronic company: W-115T. At this time, when the pH of the system did not become 4 or less, adjustment was performed by adding 0.3 N nitric acid. Thereafter, filtration was performed.

[Step of washing with ion exchange water]
After repeating the step of washing with a treatment solution having a pH of 9 or more and pH 10 or less and the step of washing with an ion exchange resin while being treated with ultrasonic waves after being adjusted to pH 4 or less in Example 1 above, It was re-dispersed in 30 ° C. ion-exchanged water of 20 times the solid amount of toner and washed three times with water.

  [Step of washing with a treatment solution having a pH of 9 or more and pH 10 or less], [Step of washing with an ion exchange resin while being treated with ultrasonic waves after being adjusted to pH 4 or less], and [Ion-exchange water] A series of washing in the step of washing] is referred to as “washing (1)”.

-Drying of toner and evaluation of physical properties-
After the cleaning (1) was completed, the toner was dried by cyclone collection using a loop type airflow dryer to obtain a toner (1) having a moisture content of 0.6%.
Table 2 shows the results of measuring the ammonium ion content in the toner obtained, the amount of ammonium ions contained in the toner surface, and the reduced amount of ammonium ions by the above method.
Further, Table 2 shows the measurement results of the volume average particle size distribution index GSD _v , the number average particle size distribution index GSD _p , the volume average particle diameter, and the average circularity of the toner.

<Example 2 to Example 3: Production of Toner (2) from Toner (2)>
A moisture content of 0 was obtained in the same manner as in Example 1, except that the amorphous polyester resin dispersion (A3) was used instead of the amorphous polyester resin dispersion (A2) instead of the amorphous polyester resin dispersion (A1). 6% toner (2) and 0.6% moisture toner (3) were obtained.
Table 2 shows the results of measuring the ammonium ion content, the ammonium ion reduction amount, and the amount of ammonium ions contained in the toner surface by the above methods. Table 2 also shows the measurement results of the volume average particle size distribution index GSD _v , the number average particle size distribution index GSD _p , the volume average particle diameter, and the average circularity.

<Example 4: Production of toner (4)>
Except for the crystalline polyester resin dispersion (A1), the amorphous polyester resin dispersion (A1) was replaced with 290.7 (293.7) parts in the production process of the toner (1) in Example 1. In the same manner as in Example 1, a toner (4) having a moisture content of 0.5% was obtained.
Table 2 shows the results of measuring the ammonium ion content, the ammonium ion reduction amount, and the amount of ammonium ions contained in the toner surface by the above methods. Table 2 also shows the measurement results of the volume average particle size distribution index GSD _v , the number average particle size distribution index GSD _p , the volume average particle diameter, and the shape average circularity.

<Example 5: Production of toner (5)>
In the production process of the toner (1) in Example 1, [Step of washing with a treatment liquid having a pH of 9 or more and pH 10 or less] and [Step of washing with an ion exchange resin while being treated with ultrasonic waves after being adjusted to pH 4 or less] A toner (5) having a moisture content of 0.6% was obtained in the same manner as in Example 1 except that the number of repetitions was changed to 2 and the number of subsequent water washings was changed to 2 (washing (2) above).
Table 2 shows the results of measuring the ammonium ion content, the ammonium ion reduction amount, and the amount of ammonium ions contained in the toner surface by the above methods. Table 2 also shows the measurement results of the volume average particle size distribution index GSD _v , the number average particle size distribution index GSD _p , the volume average particle diameter, and the average circularity.

<Comparative Example 1 to Comparative Example 4: Production of Toner (6) to Toner (9)>
In the same manner as in Example 1, except that the non-crystalline polyester resin dispersion (B4) was used instead of the non-crystalline polyester resin dispersion (A1), water was used. Toner (9) was obtained from toner (6) having a rate of 0.6%.
Table 2 shows the results obtained by measuring the ammonium ion content, the ammonium ion reduction amount, and the amount of ammonium ions contained in the toner surface by the above methods. Table 2 also shows the measurement results of the volume average particle size distribution index GSD _v , the number average particle size distribution index GSD _p , the volume average particle diameter, and the average circularity.

<Comparative Example 5: Production of toner (10)>
In the production process of the toner (3) in Example 3, the toner (10) having a moisture content of 0.6% was obtained in the same manner as in Example 1 except that the following process was performed instead of the above-described cleaning (1) process. Obtained.
Specifically, it was redispersed in ion-exchanged water at 25 ° C., which is 20 times the amount of toner solids, and washing with water was repeated 5 times.
Table 2 shows the results of measuring the ammonium ion content, the ammonium ion reduction amount, and the amount of ammonium ions contained in the toner surface by the above methods. Table 2 also shows the measurement results of the volume average particle size distribution index GSD _v , the number average particle size distribution index GSD _p , the volume average particle diameter, and the average circularity.

<Comparative Example 6: Production of toner (11)>
-Amorphous polyester resin (1) 790 parts-Crystalline polyester resin (1) 80 parts-Paraffin wax (manufactured by Nippon Seiwa Co., Ltd., HNP-9, melting point: 75 ° C) 80 parts-Cyan pigment (Daisensei) Chemical Blue, Pigment Blue 15: 3 (copper phthalocyanine))
50 copies

The raw materials were mixed with a Henschel mixer, melt-kneaded with a Banbury mixer, rolled, and roughly crushed with a hammer mill. Next, the mixture was pulverized to 6.4 μm with a jet mill pulverizer and classified with an elbow jet classifier to obtain toner (11).
Table 2 shows the results of measuring the ammonium ion content, the ammonium ion reduction amount, and the amount of ammonium ions contained in the toner surface by the above methods. Table 2 also shows the measurement results of the volume average particle size distribution index GSD _v , the number average particle size distribution index GSD _p , the volume average particle diameter, and the average circularity.

[Image formation]
<External toner adjustment>
Silica particles having a primary particle size of 40 nm subjected to surface hydrophobization treatment as an external additive with respect to 100 parts of the toner (from toner (1) to toner (11)) (Nippon Aerosil Co., Ltd., hydrophobic silica: RX50) 0.0% and 1.0% of metatitanic acid compound particles having an average primary particle diameter of 20 nm, which is a reaction product obtained by treating 100 parts of metatitanic acid with 40 parts of isobutyltrimethoxysilane and 10 parts of trifluoropropyltrimethoxysilane. Add and mix for 5 minutes with a Henschel mixer. Further, an externally added toner was obtained by passing through an ultrasonic vibration sieve (Dalton).

<Carrier adjustment>
Ferrite particles (average particle size: 35 μm) 100 parts Toluene 14 parts Perfluoroacrylate copolymer (critical surface tension 24 mN / m) 1.6 parts Carbon black (“VXC-72” manufactured by Cabot Corporation, resistance 100 Ωcm Less than)
0.12 parts cross-linked melamine resin particles (average particle size; 0.3 μm, toluene insoluble) 0.3 parts Carbon black diluted with toluene and dispersed in a perfluoroacrylate copolymer using a sand mill, Furthermore, it stirred with the stirrer for 10 minutes and prepared the film layer forming liquid. Next, this coating layer forming solution and ferrite particles are put into a vacuum degassing type kneader and stirred at a temperature of 60 ° C. for 30 minutes, and then the pressure is reduced to distill off toluene, thereby forming a resin coating layer and carrier. Obtained.

<Adjustment of developer>
36 g of the externally added toner and 414 g of the carrier were placed in a 2 L V blender, stirred for 20 minutes, and then sieved with a mesh having a pore size of 212 μm to prepare a developer.

<Fixing device preparation>
-Production of heating roll-
Molded with a fluororesin tube with an outer diameter of 50 mm, length of 340 mm, and thickness of 30 μm and a metallic aluminum hollow core core coated with an adhesive primer (silicone-modified polyimide primer, manufactured by Toray Dow Silicone) on the inner surface of the tube Then, a liquid silicone rubber having a layer thickness of 3 mm was injected between the fluororesin tube and the core, and then the silicone rubber was vulcanized by heat treatment (150 ° C. × 2 hrs) to prepare a heating roll having rubber elasticity.

-Production of pressure belt-
After applying fluororesin dispersion paint by dip coating on the surface of polyimide endless belt with outer diameter of 68mm, length of 340mm, thickness of 75μm, the pressure belt is baked by heat treatment (350 ° C x 1hrs). Produced.

[Evaluation]
As an image forming apparatus, DocuCentreColor 6550 (manufactured by Fuji Xerox Co., Ltd.) was used, and the obtained developer was filled in a Kuro developing device of the image forming apparatus, and the following evaluation was performed. As the heating roll and pressure belt of the fixing device, the heating roll and pressure belt were used.

<Evaluation of electrification>
The obtained developer was filled in a developing device and seasoned for 24 hours in a low temperature and low humidity environment (10 ° C./15% RH). Thereafter, the developing machine was spun for 3 minutes under the same environment, and the charge amount of the developer was measured using a blow-off charge amount measuring device (TB200, manufactured by Toshiba Corporation) under low temperature and low humidity. The results are shown in Table 3.

  Further, the obtained developer was filled in a developing device and seasoned for 24 hours in an environment of high temperature and high humidity (30 ° C./80% RH). Thereafter, the developing machine is idled for 3 minutes in the same environment, and the charge amount of the developer is charged with a blow-off charge amount measuring device (TB200, manufactured by Toshiba Corporation) under high temperature and high humidity (initial charge amount). Was measured. The results are shown in Table 3.

<Evaluation of low-temperature fixability>
An unfixed image was formed by the image forming apparatus from which the fixing device was removed. The image condition was a solid image of 40 mm × 50 mm, the toner amount was 1.5 mg / cm ² , and the recording paper was mirror-coated platinum paper (basis weight: 127 gsm). Next, the fixing machine using the heating roll and the pressure belt is remodeled so that the fixing temperature is variable, and the fixing speed is increased in steps from 320 ° C. to 200 ° C. at a fixing speed of 320 mm / sec. The low-temperature fixability of the image was evaluated. Low-temperature fixability is achieved by bending a good fixed image with a certain load weight without image loss due to defective mold release, and then marking the degree of image loss at that portion, so that the fixing temperature at which a certain grade or higher is reached is minimized. The fixing temperature was used as an index of low-temperature fixability. The minimum fixing temperature is preferably 140 ° C. or lower. The results are shown in Table 3.

<Evaluation of odor>
The image forming apparatus was used for sensory evaluation of odor generated after 2000 sheets of images were formed at a fixing speed of 320 mm / sec and a fixing temperature of 200 ° C. Specifically, the modified machine is placed in a closed booth with a floor area of 4.5 m × 4.5 m and a height of 3 m to form the image, and the odor in the booth immediately after the 2000-sheet image is formed. Judgment was made by 20 subjects. The results are shown in Table 3. The evaluation criteria are as follows, and there is no practical problem if it is G1 or G2.

G1: 0 people who felt odor G2: 1 to 5 people who felt odor G3: 6 to 20 people who felt odor

<Evaluation of charger contamination>
Using the above image forming apparatus, 10,000 sheets of images were continuously formed in an environment of a temperature of 30 ° C. and a humidity of 80%. Thereafter, the image forming apparatus was turned off and left for 24 hours in an environment of 30 ° C. and 80% humidity. Thereafter, an A3 full-scale halftone image having a Cin (image density) of 20% was formed, and image contamination of this halftone image was evaluated by sensory evaluation to evaluate charger contamination. The results are shown in Table 3. The evaluation criteria are as follows, and there is no practical problem if it is G1 or G2.

G1: No image unevenness was observed.
G2: Image unevenness was slightly observed, but was within an allowable range.
G3: Image unevenness was observed, and this was a practically problematic level.

<Evaluation of fixing unit deterioration>
The image forming apparatus including the heating roll and the pressure belt is surrounded by a hood that is open on only one side of 1.0 m × 1.0 m, and FX color paper (gray, manufactured by Fuji Xerox Co., Ltd.) is used as a recording medium. 10,000 images were continuously formed in an environment of 80 ° C. and humidity of 80%. The fixing speed is 320 mm / sec and the fixing temperature is 220 ° C. Thereafter, the deterioration state of the elastic layer (silicone rubber) of the heating roll was visually observed. The results are shown in Table 3. The evaluation criteria are as follows, and there is no practical problem if it is G1 or G2.

G1: No deterioration of the elastic layer was observed.
G2: Although slight deterioration of the elastic layer was observed, it was within an allowable range.
G3: Deterioration of the elastic layer was observed, and it was a level causing a problem in practical use.

As can be seen from Table 3, in the example, compared with the comparative example, the chargeability is excellent, the charging environment dependency is small, the generation of odor is suppressed, the image unevenness due to the contamination of the charger is suppressed, and the fixing device is deteriorated. Is suppressed.
On the other hand, in Comparative Example 1, there were many coarse powders in the toner, and there were difficulties in manufacturability such as rapid particle size growth. Further, the charge distribution was deteriorated due to the deterioration of the toner particle size distribution, and the image fog was observed because the toner charge amount was small.
In Comparative Example 2, there were difficulties in manufacturability such as slow growth of particle size and slow shape change. Moreover, since the difference in charging due to the environment is large, it has been difficult to obtain a stable concentration.
Furthermore, in Comparative Example 6, the powder flowability was deteriorated due to the release agent being deposited on the toner surface, so that the charge distribution with time was deteriorated, and image fogging due to this was observed.

1 is a schematic configuration diagram illustrating an example of an image forming apparatus according to an embodiment. It is a schematic structure figure showing an example of a process cartridge concerning an embodiment.

Explanation of symbols

1Y, 1M, 1C, 1K, 107 photoconductor (image carrier)
2Y, 2M, 2C, 2K, 108 Charger 3Y, 3M, 3C, 3K Laser beam 3 Exposure device 4Y, 4M, 4C, 4K, 111 Developing device (developing means)
5Y, 5M, 5C, 5K Primary transfer rollers 6Y, 6M, 6C, 6K, 113 Photoconductor cleaning device (cleaning means)
8Y, 8M, 8C, 8K Toner cartridge 10Y, 10M, 10C, 10K Unit 20 Intermediate transfer belt 22 Drive roller 24 Support roller 26 Secondary transfer roller (transfer means)
28, 115 Fixing device (fixing means)
30 Intermediate transfer member cleaning device 112 Transfer device 116 Mounting rail 117 Opening 118 for static elimination exposure Opening 200 for exposure Process cartridge,
P, 300 Recording paper (transfer object)

Claims (8)

Including a polyester resin, a colorant and ammonium ions;
The acid value of the polyester resin is 5 mgKOH / g or more and 25 mgKOH / g or less,
The ammonium ion content in the toner is 20 ppm or more and 400 ppm or less,
A toner for developing an electrostatic charge image, wherein the amount of ammonium ion reduction in the toner by exposing the toner to air at 30 ° C. and 80% humidity for 6 hours is 120 ppm or less.   The electrostatic charge image developing toner according to claim 1, wherein the polyester resin contains a crystalline polyester resin. Resin for adjusting a resin particle dispersion in which resin particles are dispersed by adding a water-based solvent to a resin-containing liquid containing at least a polyester resin, ammonia and an organic solvent, phase inversion emulsification, and removing the organic solvent A particle dispersion adjusting step;
An aggregated particle forming step of forming aggregated particles containing at least the resin particles;
A toner particle forming step of forming toner particles by heating the aggregated particle dispersion and fusing the aggregated particles;
A cleaning step of cleaning the toner particles;
The method for producing a toner for developing an electrostatic charge image according to claim 1, comprising:   The cleaning step includes a step of cleaning the toner particles with a treatment liquid having a pH of 9 or more, a pH of 10 or less, a step of cleaning the toner particles with an ion exchange resin while treating with ultrasonic waves after the pH of the toner particles is adjusted to 4 or less, and the toner. The method for producing a toner for developing an electrostatic charge image according to claim 3, further comprising a step of washing the particles with ion-exchanged water.   An electrostatic charge image developing developer comprising at least the electrostatic charge image developing toner according to claim 1. Contains a developer that is detached from the image forming apparatus and supplied to at least developing means provided in the image forming apparatus;
The developer cartridge for developing an electrostatic charge image according to claim 5, wherein the developer is the developer for developing an electrostatic charge image according to claim 5. An electrostatic latent image carrier;
Charging means for charging the surface of the electrostatic latent image holding member by discharging;
Electrostatic latent image forming means for forming an electrostatic latent image on the surface of the electrostatic latent image holding member;
Developing means for developing the electrostatic latent image into a toner image with a developer;
Transfer means for transferring the toner image on the surface of the electrostatic latent image holding member to the surface of the transfer target;
Fixing means for heating and fixing the toner image transferred to the transfer body,
The image forming apparatus according to claim 5, wherein the developer is a developer for developing an electrostatic image according to claim 5. A developer for storing the developer for developing an electrostatic charge image according to claim 5 and developing the electrostatic latent image formed on the surface of the electrostatic latent image holding member into a toner image by the developer for developing an electrostatic charge image. Means,
An electrostatic latent image holding member, a charging unit for charging the surface of the electrostatic latent image holding member by discharge, and a toner removing unit for removing toner remaining on the surface of the electrostatic latent image holding member. And at least one selected,
A process cartridge which is detachable from an image forming apparatus.

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