JP5298716B2 - Electrostatic image developing toner, electrostatic image developer, toner cartridge, process cartridge, and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a toner for electrostatic charge image development, which is free from hot offset, is easily deinked in a deinking process after used in a copying machine or a printer and allows easy recycling of a paper sheet, and to provide an electrostatic charge image developer, a toner cartridge, a process cartridge and an image forming apparatus including the above toner for electrostatic charge image development. <P>SOLUTION: The toner for electrostatic charge image development is characterized in that when the toner is held in water with a pH8 at 90&deg;C for one hour, the retention rate A of the weight average molecular weight is not less than 95%, and when the toner is held in water with a pH9 at 98&deg;C for one hour, the retention rate B of the weight average molecular weight is not more than 70%. The electrostatic charge image developer, the toner cartridge, the process cartridge and the image forming apparatus includes the above toner. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to an electrostatic image developing toner, an electrostatic image developer, a process cartridge, and an image forming apparatus.

A method of visualizing an image through an electrostatic charge image such as electrophotography is currently used in various fields. In electrophotography, an electrostatic latent image is formed on a photoreceptor by charging and exposure processes, the electrostatic latent image is developed with a developer containing toner, and visualized through a transfer and fixing process. Various types of resins have been studied so far, but at present, styrene resins, polyester resins, and epoxy resins are mainly used.
By the way, from the viewpoint of environmental protection and waste disposal in recent years, attempts to recycle used waste paper have become increasingly important year after year. In particular, copiers and printers using the electrophotographic method have become widespread in recent years, and the amount of paper discarded from copiers and printers has increased. Proposed attempts to obtain deinked pulp from these used papers Has been.

  Moreover, the technique (for example, refer patent document 1) using degradable polyester, such as poly (alpha) hydroxy carboxylic acid, the technique using together poly (alpha) hydroxy carboxylic acid and other polyester resin, a styrene resin, or a polyol type | system | group A technique using a resin together (for example, see Patent Documents 2 to 4), or a technique using a biodegradable polyhydroxyalkanoate such as poly-3-hydroxybutyrate as a binder resin (for example, see Patent Document 5), a specific A technique using a polylactic acid resin (see, for example, Patent Document 6) has been introduced. A technique using aspartic acid / glutamic acid and hydroxycarboxylic acid has also been introduced (see, for example, Patent Document 7).

Furthermore, the technique which provides hydrolysis resistance by using the monomer which has a specific structure for a polyester resin is proposed (for example, refer patent document 8).
International Publication No. 92/01245 Pamphlet JP 2002-55491 A JP 2002-55489 A JP 2002-55490 A JP 2002-327047 A Japanese Patent Laid-Open No. 7-120975 Japanese Patent Laid-Open No. 2004-12934 JP 2008-7527 A

As described above, when obtaining deinked pulp from used paper, it is important from the viewpoint of paper recycling and recycling to efficiently remove the toner fixed on the paper. As described above, the styrene resins, polyester resins, and epoxy resins that are currently used mainly have low hydrolyzability and are difficult to separate from paper fibers. The techniques proposed in Patent Documents 1 to 7 are intended to improve the above problems.
However, for example, since the toner by the so-called emulsion aggregation / unification method is mainly produced in water, the use of these resins has a defect that hydrolysis proceeds during toner production. It was difficult to secure the deinking property with the toner by the coalescence method.
In the emulsion aggregation / unification method, a resin particle dispersion is prepared by emulsion polymerization or phase inversion emulsification, and the resulting particle dispersion is agglomerated and then heated to a temperature higher than the glass transition temperature. The toner particles are formed by melting and coalescing the particles. In general, the temperature fluctuates from room temperature to about 95 ° C. and the pH from about 2 to 10 throughout these toner-forming steps.

The technique proposed in Patent Document 8 is a technique proposed for preventing the progress of hydrolysis during the toner production described above. Although such a technique can be expected to improve hydrolysis resistance, it has a deinking property. It is clear that it will decline.
The present invention relates to an electrostatic charge image developing toner that suppresses filming on an image carrier and is easily deinked in a deinking process after use in a copying machine, a printer, etc., and facilitates paper recycling. An object of the present invention is to provide an electrostatic charge image developer containing the electrostatic charge image developing toner, a toner cartridge, a process cartridge, and an image forming apparatus.

The above-mentioned subject is achieved by the following present invention.
That is, in the invention according to claim 1, the retention A of the weight average molecular weight measured for the tetrahydrofuran-soluble content when held in water at 90 ° C. for 1 hour at pH 8 is 95% or more, and water at pH 9 at 98 ° C. tetrahydrofuran-retention B is der 70% or less of the measured weight average molecular weight for the matter of when held 1 hour is, by mixing a resin particle dispersion and colorant dispersion, a metal sulfate and poly aluminum chloride Produced through an agglomerated particle forming step using the agglomerated particles, and a fusion or coalescence of the aggregated particles by heating to a temperature equal to or higher than the glass transition temperature of the resin particles. An electrostatic charge image developing toner comprising a polyester resin .

The invention according to claim 2 is that the non-crystalline polyester resin contains 20 mol% or more of a divalent alcohol component represented by the following general formula (A) as an alcohol component constituting the resin. The electrostatic charge image developing toner according to claim 1 , wherein
Formula (A)
HO— (CH ₂ ) _x —OH
(In general formula (A), x represents an integer of 2 or more and 9 or less.)

Invention, developing the electrostatic image according to claim 1 or claim 2, wherein the content of the polyester resin contained in the toner for developing electrostatic images is 3 mass% or more according to claim 3 Toner.

The invention according to claim 4 is the electrostatic image developing toner according to any one of claims 1 to 3 , characterized by containing 0.02% or more of elemental sulfur.

According to a fifth aspect of the present invention, there is provided an electrostatic charge image development comprising a toner, wherein the toner is the electrostatic charge image developing toner according to any one of the first to fourth aspects.

According to a sixth aspect of the present invention, there is provided a toner cartridge comprising at least a toner, wherein the toner is the electrostatic image developing toner according to any one of the first to fourth aspects.

According to a seventh aspect of the present invention, there is provided a process cartridge comprising at least a developer holder and containing the electrostatic charge image developer according to the fifth aspect.

According to an eighth aspect of the present invention, there is provided an image carrier, developing means for developing the electrostatic image formed on the image carrier as a toner image with a developer, and recording the toner image formed on the image carrier. Transfer means for transferring onto the medium, fixing means for fixing the toner image transferred onto the recording medium, and cleaning means for cleaning residual toner on the image carrier after transfer, wherein the developer is An image forming apparatus comprising the electrostatic charge image developer according to claim 5 .

The invention according to claim 9 is the image forming apparatus according to claim 8 , wherein the cleaning means has a rotating brush.

According to the first aspect of the present invention, the occurrence of filming on the image carrier is suppressed, and the ink is easily deinked in the deinking process after use in a copying machine or a printer, and the paper is recycled. Can be obtained.
According to the first aspect of the present invention, the occurrence of filming on the image carrier is suppressed, and in the deinking process after use in a copying machine or printer, the ink is easily deinked and the paper can be recycled. An electrostatic image developing toner produced by an easy aggregation and coalescence method can be obtained.

According to the second aspect of the present invention, the occurrence of filming on the image carrier is suppressed, and the deinking process after use in a copying machine or a printer is more easily deinked and the paper is recycled. As a result, a toner for developing an electrostatic charge image can be obtained.

According to the invention of claim 3 of the present invention, the occurrence of filming on the image carrier is suppressed, and the deinking process after use in a copying machine or a printer is more easily deinked and the paper can be recycled. A toner for developing an electrostatic charge image that becomes easier can be obtained.
According to the fourth aspect of the present invention, the occurrence of filming on the image carrier is suppressed, and the deinking process after use in a copying machine, a printer or the like is more easily deinked and the paper is recycled. As a result, a toner for developing an electrostatic charge image can be obtained.

According to the invention according to claim 5 of the present invention, the occurrence of filming on the image carrier is suppressed, and in the deinking process after use in a copying machine or a printer, the ink is easily deinked and the paper can be recycled. An easy electrostatic charge image developer can be obtained.

According to the invention of claim 6 of the present invention, the occurrence of filming on the image carrier is suppressed, and the ink is easily deinked in the deinking process after use in a copying machine or a printer, and the paper is recycled. Can be obtained.

According to the invention of claim 7 of the present invention, the occurrence of filming on the image carrier is suppressed, and the ink is easily deinked in the deinking process after use in a copying machine or a printer, and the paper is recycled. Can be obtained.

According to the eighth aspect of the present invention, the occurrence of filming on the image carrier is suppressed, and the ink is easily deinked in the deinking process after use in a copying machine or a printer, and the paper is recycled. Can be obtained.
According to the ninth aspect of the present invention, an image forming apparatus that further suppresses the occurrence of filming on the image carrier can be obtained.

Hereinafter, embodiments of the present invention will be described in detail.
<Toner for electrostatic image development>
The toner for developing an electrostatic charge image of the present embodiment (hereinafter sometimes referred to as “the toner of the present embodiment”) was measured by weight average measured for tetrahydrofuran-soluble content when held in water at 90 ° C. and pH 8 for 1 hour. The molecular weight retention ratio A is 95% or more, and the weight average molecular weight retention ratio B measured for the tetrahydrofuran-soluble content when held in water at pH 9 at 98 ° C. for 1 hour is 70% or less. . However, in the electrostatic charge developing toner of this embodiment, a resin particle dispersion and a colorant dispersion are mixed, and an aggregated particle forming step of forming aggregated particles using a metal sulfate and polyaluminum chloride; and the resin A toner for developing an electrostatic charge image, which is produced by fusing and coalescing the aggregated particles by heating to a temperature equal to or higher than the glass transition temperature of the particles and containing an amorphous polyester resin, is applied. .

Here, the retention of the weight average molecular weight when held in water at 90 ° C. and pH 8 for 1 hour is determined as follows.
(1) First, a weight average molecular weight of a solution obtained by dissolving 0.2 g of a sample (toner) in 99.8 g of tetrahydrofuran is measured, and the value is defined as A1.
(2) Next, 10 g of a sample was put into 100 g of ion-exchanged water and dispersed for 2 minutes with an ultrasonic disperser to prepare a toner dispersion. Further, the dispersion was heated to 90 ° C. with stirring, and after reaching 90 ° C., the pH was adjusted to 8.0 ± 0.05 with an aqueous sodium hydroxide solution and held for 1 hour.
(3) After 1 hour, the dispersion is gradually cooled, cooled to 25 ° C., adjusted to 7.0 ± 0.1 with an aqueous nitric acid solution, and freeze-dried to obtain a toner solid content. A weight average molecular weight of a solution obtained by dissolving 0.2 g of the obtained toner solid content in 99.8 g of tetrahydrofuran is measured, and the value is defined as A2.
(4) The retention rate A is obtained from the following formula.
Retention rate A (%) = (A2 / A1) × 100

Further, the retention B of the weight average molecular weight when held in water at 98 ° C. and pH 9 for 1 hour is determined as follows.
(1) First, a weight average molecular weight of a solution obtained by dissolving 0.2 g of a sample (toner) in 99.8 g of tetrahydrofuran is measured, and the value is defined as B1.
(2) Next, 10 g of a sample was put into 100 g of ion-exchanged water and dispersed for 2 minutes with an ultrasonic disperser to prepare a toner dispersion. Further, the dispersion was heated to 98 ° C. with stirring, and after reaching 98 ° C., the pH was adjusted to 9.0 ± 0.05 with an aqueous sodium hydroxide solution and held for 1 hour.
(3) After 1 hour, the dispersion is gradually cooled, cooled to 25 ° C., adjusted to 7.0 ± 0.1 with an aqueous nitric acid solution, and freeze-dried to obtain a toner solid content. A weight average molecular weight of a solution obtained by dissolving 0.2 g of the obtained toner solid content in 99.8 g of tetrahydrofuran is measured, and the value is defined as B2.
(4) The retention rate A is obtained from the following formula.
Retention rate B (%) = (B2 / B1) × 100

The weight average molecular weight was measured under the following conditions using GPC (gel permeation chromatography).
Tosoh Corporation HLC-8120GPC, SC-8020 apparatus was used, TSK geli, SuperHM-H (6.0 mm ID × 15 cm × 2) was used as the column, and THF (tetrahydrofuran) was used as the eluent. As experimental conditions, the sample concentration was 0.5%, and the flow rate was 0.6 ml / min. Sample injection volume 10 μl, measurement temperature 40 ° C., calibration curve is A-500, F-1, F-10, F-80, F-380, A-2500, F-4, F-40, F-128, Made from 10 samples of F-700. The data collection interval in sample analysis was 300 ms.

  The toner of the present exemplary embodiment is characterized in that a weight-average molecular weight retention ratio B measured for tetrahydrofuran-soluble content when held in water at 98 ° C. and pH 9 for 1 hour is 70% or less. Here, holding the toner in water at 98 ° C. and pH 9 is a hypothesis of the deinking process after use in a copying machine or printer, and if the holding ratio B is 70% or less, the deinking process is performed. In the ink process, the toner component is sufficiently decomposed by hydrolysis under an alkali or the like, and is easily deinked. On the other hand, when the retention ratio B exceeds 70%, the toner component is not sufficiently decomposed due to hydrolysis under alkali in the deinking step or the paper recycling step, and the toner is not detached from the paper fiber. It becomes easy to remain in. The retention rate B is preferably 65% or less, and more preferably 60% or less.

  The toner of the present exemplary embodiment is characterized in that the retention A of the weight average molecular weight measured for the tetrahydrofuran-soluble content when held in water at 90 ° C. and pH 8 for 1 hour is 95% or more. Here, the retention of the toner in water at 90 ° C. and pH 8 is a hypothetical condition at the time of toner production. For example, in the emulsion aggregation / unification method, a temperature change of about 25 ° C. to 95 ° C. and a pH change of about 2 to 10 usually occur. The low pH (acid side) state mainly occurs in the initial aggregation process, and the temperature at that time is about 25 ° C. to 50 ° C. Conversely, the high pH (alkaline side) environment mainly stops aggregation. Since it is generated in the process, the temperature is still about 50 ° C. The high temperature environment is the melting and coalescence process. In this process, the pH is usually about 6 to 8, and an excessively stressed environment such as 95 ° C./pH 10 or 95 ° C./pH 2 is a normal manufacturing process. Does not occur.

When the retention ratio A is less than 95%, the decomposition of the resin proceeds due to hydrolysis or the like during toner production. As a result, a low molecular weight component is generated, and image quality failure due to deterioration of powder characteristics, charging failure, or adhesion (filming) to the photoreceptor is likely to occur. Further, since the molecular weight of the original resin is lowered, there arises a problem that hot offset is likely to occur during fixing. The retention A is preferably 96% or more, and more preferably 98% or more.
From the above, the toner of the present embodiment has a retention rate A of 95% or more and a retention rate B of 70% or less, so that hot offset does not occur and after use in a copier or printer. In the deinking process, the paper is easily deinked and the paper can be easily recycled.

In the toner of the present exemplary embodiment, for example, the retention rate A is controlled to 95% or more and the retention rate B is controlled to 70% or less by applying at least one of the following (1) to (5).
(1) A polyester resin is used as the binder resin.
(2) The polyester resin contains a divalent alcohol component represented by the following general formula (A) in an amount of 20 mol% or more of the total alcohol components.
(3) The content of the polyester resin in the toner is 3% by mass or more.
(4) A metal sulfate salt is used in the production (as a result, the obtained toner contains elemental sulfur).
(5) When the toner is produced by the emulsion aggregation method, polyaluminum chloride is used together with the metal sulfate salt of (4).
Hereinafter, the toner of the present exemplary embodiment will be described in detail including a method for controlling the retention rate A to 95% or more and the retention rate B to 70% or less for each configuration.

(Binder resin)
Examples of the binder resin used in the toner of the present embodiment include polyester resin, polyurethane resin, and epoxy resin. As described above, the retention rate A is controlled to 95% or more and the retention rate B is controlled to 70% or less. A polyester resin is preferred because of its ease. Examples of the polyester resin include a crystalline polyester resin and an amorphous polyester resin, both of which can be used in this embodiment. In addition, the crystalline polyester resin and the non-crystalline polyester resin may be used alone as the binder resin, but it is preferable to use them in combination.

  In the present embodiment, the “crystalline polyester resin” refers to a resin having a clear endothermic peak rather than a stepwise endothermic amount change in differential scanning calorimetry (DSC). On the other hand, the resin in which the stepwise endothermic change is recognized in DSC means the amorphous polyester resin in this embodiment.

-Crystalline polyester resin-
In the toner of this embodiment, low-temperature fixing is realized by including a crystalline polyester resin. The low-temperature fixing means that the toner is heated and fixed at about 120 ° C. or less (process speed of 100 mm / s, 80 gsm of paper, toner loaded amount per unit area of 1.5 mg / cm ² ). .
In the present embodiment, the crystalline polyester resin refers to a resin having a clear endothermic peak instead of a stepwise endothermic amount change in differential scanning calorimetry (DSC) as described above, and a resin having the endothermic peak. As long as it is a polymer obtained by copolymerizing other components with respect to the crystalline polyester main chain, this copolymer is also a crystalline polyester resin if the other components are 50 constituent mol% or less. That is, a crystalline polyester resin is obtained by showing an endothermic peak. Hereinafter, although the preferable example of crystalline polyester is shown, it is not limited to what is shown here.

In the crystalline polyester resin, examples of the acid to be an acid-derived constituent component include various dicarboxylic acids. Among them, aliphatic dicarboxylic acids and aromatic dicarboxylic acids are preferable, and aliphatic dicarboxylic acids are particularly linear. The carboxylic acid is preferred. The dicarboxylic acid as the acid-derived constituent component is not limited to one type, and may include two or more types of dicarboxylic acid-derived constituent components. Further, the dicarboxylic acid may contain a sulfonic acid group in order to improve the emulsifiability in the emulsion aggregation method.
The “acid-derived constituent component” refers to a constituent portion that was an acid component before the synthesis of the polyester resin, and the “alcohol-derived constituent component” was an alcohol component before the synthesis of the polyester resin. Refers to the component part.

  Examples of the aliphatic dicarboxylic acid include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelic acid, sebacic acid, 1,9-nonanedicarboxylic acid, and 1,10-decanedicarboxylic acid. Acid, 1,11-undecanedicarboxylic acid, 1,12-dodecanedicarboxylic acid, 1,13-tridecanedicarboxylic acid, 1,14-tetradecanedicarboxylic acid, 1,16-hexadecanedicarboxylic acid, 1,18-octadecanedicarboxylic acid Or lower alkyl esters and acid anhydrides thereof, but are not limited thereto. Among these, considering availability, adipic acid, sebacic acid, 1,10-decanedicarboxylic acid, and 1,12-dodecanedicarboxylic acid are preferable.

  An aromatic dicarboxylic acid may be added to the aliphatic dicarboxylic acid. Examples of the aromatic dicarboxylic acid include terephthalic acid, isophthalic acid, orthophthalic acid, t-butylisophthalic acid, and 2,6-naphthalenedicarboxylic acid. Acid, 4,4′-biphenyldicarboxylic acid, and the like. Among them, terephthalic acid, isophthalic acid, and t-butylisophthalic acid are preferable from the viewpoint of availability and easy emulsification. The amount of these aromatic dicarboxylic acids added is preferably 20 constituent mol% or less, more preferably 10 constituent mol% or less, and even more preferably 5 constituent mol% or less. If the amount of the aromatic dicarboxylic acid added exceeds 20 mol%, the emulsifiability becomes difficult, the crystallinity is hindered, and the image gloss characteristic of the crystalline polyester resin cannot be obtained. May cause image storage stability to deteriorate.

  In the crystalline polyester resin, the alcohol to be an alcohol-derived constituent component is preferably an aliphatic diol. Specific examples of the aliphatic diol include 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, Examples include, but are not limited to, 11-undecanediol, 1,12-dodecanediol, 1,13-tridecanediol, 1,14-tetradecanediol, 1,18-octadecanediol, 1,20-eicosanediol, and the like. Is not to be done. Among these, considering availability, ethylene glycol, 1,4-butanediol, 1,6-henquinsandiol, 1,9-nonanediol, and 1,10-decanediol are preferable.

The production of the crystalline polyester resin can be carried out at a polymerization temperature of 180 ° C. or higher and 230 ° C. or lower. If necessary, the reaction system is reduced in pressure and reacted while removing water and alcohol generated during condensation. .
When the polymerizable monomer is not dissolved or compatible at the reaction temperature, a solvent having a high boiling point may be added as a solubilizer and dissolved. In the polycondensation reaction, the dissolution auxiliary solvent is distilled off. If there is a polymerizable monomer having poor compatibility in the copolymerization reaction, the polymerizable monomer having poor compatibility and the polymerizable monomer and the acid or alcohol to be polycondensed are condensed in advance. And then polycondensation with the main component.

  Catalysts usable 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; zinc, manganese, antimony, titanium, tin, zirconium, germanium and the like Metal compounds; phosphorous acid compounds; phosphoric acid compounds; and amine compounds.

  The weight average molecular weight (Mw) of the crystalline polyester resin is preferably in the range of 6,000 to 35,000, more preferably in the range of 6,000 to 30,000. When the molecular weight (Mw) is less than 6,000, the strength of the fixed image against bending resistance may be reduced. When the weight average molecular weight (Mw) exceeds 35,000, the high molecular weight amorphous resin may It may be difficult to take in.

  The weight average molecular weight can be measured by gel permeation chromatography (GPC). The molecular weight measurement by GPC was performed with a THF solvent using a Tosoh column / TSKgel Super HM-M (15 cm) using a Tosoh GPC / HLC-8120 as a measuring device. The weight average molecular weight is calculated from the measurement result using a molecular weight calibration curve prepared with a monodisperse polystyrene standard sample.

The melting temperature (Tm) of the crystalline polyester resin used in the present embodiment is preferably in the range of 60 ° C. or higher and 120 ° C. or lower, and more preferably in the range of 70 ° C. or higher and 100 ° C. or lower. When the melting point of the crystalline polyester resin is less than 60 ° C., the powder is likely to be aggregated or the storage stability of the fixed image may be deteriorated. On the other hand, if the temperature exceeds 120 ° C., image roughness may occur and low-temperature fixability may be impaired.
In addition, melting | fusing point of the said crystalline polyester resin was calculated | required as the peak temperature of the endothermic peak obtained by the said differential scanning calorimetry (DSC).

-Amorphous polyester resin-
A known polyester resin can be used as the non-crystalline polyester resin used in the present embodiment. The amorphous polyester resin is synthesized from a polyvalent carboxylic acid component and a polyhydric alcohol component. In addition, as said amorphous polyester resin, a commercial item may be used and what was synthesize | combined may be used. The non-crystalline polyester resin may be one type of non-crystalline polyester resin or a mixture of two or more types of polyester resins.

  Examples of the polyhydric alcohol component in the amorphous polyester resin include, for example, ethylene glycol, propylene glycol, 1,4-butanediol, 2,3-butanediol, diethylene glycol, triethylene glycol, 1,5 as divalent alcohol components. -Pentanediol, 1,6-hexanediol, neopentylene glycol, 1,4-cyclohexanedimethanol, dipropylene glycol, polyethylene glycol, polypropylene glycol, bisphenol A, hydrogenated bisphenol A and the like can be used. As the trivalent or higher alcohol component, glycerin, sorbitol, 1,4-sorbitan, trimethylolpropane, or the like is used.

  Examples of the divalent carboxylic acid component condensed with the polyhydric alcohol component include aromatic carboxylic acids such as terephthalic acid, isophthalic acid, phthalic anhydride, trimellitic anhydride, pyromellitic acid, and naphthalenedicarboxylic acid; Succinic acid, alkenyl succinic acid, adipic acid, peric acid, azelaic acid, sebacic acid, 1,9-nonanedicarboxylic acid, 1,10-decanedicarboxylic acid, 1,12-dodecanedicarboxylic acid, 1,14-tetradecanedicarboxylic acid Aliphatic saturated carboxylic acids such as 1,18-octadecanedicarboxylic acid; aliphatic unsaturated dicarboxylic acids such as maleic acid, maleic anhydride, fumaric acid, itaconic acid, itaconic anhydride, citraconic acid, citraconic anhydride, and mesaconic acid Alicyclic carboxylic acids such as cyclohexanedicarboxylic acid; Beauty lower alkyl esters of these acids, such as acid anhydrides and the like, using these one or more.

Among these polycarboxylic acids, aliphatic unsaturated dicarboxylic acids have a planar structure and are preferable for increasing the affinity with a crystalline polyester resin having high linearity. In particular, fumaric acid is a double bond transester. Since the carboxylic acid is located at the position, the linearity of the resin structure is further improved, and the affinity is further improved, which is preferable.
In addition, when alkenyl succinic acid or an anhydride thereof is used, an alkenyl group having higher hydrophobicity than other functional groups is present, so that it can be more easily compatible with the crystalline polyester resin. Examples of alkenyl succinic acid components include n-dodecyl succinic acid, n-dodecenyl succinic acid, isododecyl succinic acid, isododecenyl succinic acid, n-octyl succinic acid, n-octenyl succinic acid, and acid anhydrides thereof, Examples thereof include acid chlorides and lower alkyl esters having 1 to 3 carbon atoms.

Furthermore, by containing a trivalent or higher carboxylic acid, the polymer chain can take a crosslinked structure. By taking this crosslinked structure, the crystalline polyester resin once compatible with the amorphous resin is fixed. The effect of making it difficult to separate is obtained.
Examples of the trivalent or higher carboxylic acid include trimellitic acid such as 1,2,4-benzenetricarboxylic acid and 1,2,5-benzenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, and hemimerlic acid. , Trimesic acid, merophanic acid, planitic acid, pyromellitic acid, meritic acid, 1,2,3,4-butanetetracarboxylic acid, and their acid anhydrides, acid chlorides and lower alkyl esters having 1 to 3 carbon atoms Trimellitic acid is particularly preferred. These may be used individually by 1 type and may use 2 or more types together.

  Moreover, as an acid component, it is preferable that the dicarboxylic acid component which has a sulfonic acid group other than the above-mentioned aliphatic dicarboxylic acid and aromatic dicarboxylic acid is contained. The dicarboxylic acid having a sulfonic acid group is effective in that it can favorably disperse a coloring material such as a pigment. Further, when the binder resin particle dispersion is prepared by emulsifying or suspending the entire resin in water, if the dicarboxylic acid component has a sulfonic acid group, a surfactant is not used as described later. It is also possible to emulsify or suspend.

For the above reasons, the non-crystalline polyester resin includes at least one of aliphatic unsaturated dicarboxylic acid and its anhydride, at least one of alkenyl succinic acid and its anhydride, trimellitic acid and its anhydride. It is preferable that the component made to react including at least 1 type of these is contained. Further, as described above, the amount of the aliphatic unsaturated dicarboxylic acid in the total acid component is set to be higher in the low molecular weight amorphous polyester resin than in the high molecular weight amorphous polyester resin.
The polymerization method is the same as in the case of the crystalline polyester resin.

The molecular weight of the amorphous polyester resin is not particularly limited. For example, when a high molecular weight component / low molecular weight component resin is synthesized and used as a binder resin, the weight average of the high molecular weight component resin is used. The molecular weight Mw is preferably in the range of 30,000 to 200,000, more preferably in the range of 30,000 to 100,000, and even more preferably in the range of 35,000 to 80,000.
By controlling the molecular weight of the high molecular weight component within this range, the shell effect in the aggregation step (the outermost surface is covered with an amorphous polyester resin) can be effectively expressed. When Mw exceeds 200,000, temperature and time are required for melting and merging, and the crystalline polyester resin or the like may be exposed from the inside and the shell effect may not be exhibited. On the other hand, when the molecular weight is less than 30000, the affinity due to the low molecular weight is improved, and the shell effect may not be expected.

As described above, the polyester resin (both crystalline polyester resin and non-crystalline polyester resin) is a resin that is easy to control the retention rate A to 95% or more and the retention rate B to 70% or less. As the constituent alcohol component, the divalent alcohol component represented by the following general formula (A) is preferably contained in an amount of 20 mol% or more, more preferably 25 mol% or more of the total alcohol components. Moreover, it is preferable that the ratio of the bivalent alcohol component shown with the following general formula (A) with respect to the said all alcohol component is 50 mol% or less from the viewpoint of powder fluidity | liquidity, storage property, or charging property.
Formula (A)
HO— (CH ₂ ) _x —OH
(In general formula (A), x represents an integer of 2 or more and 9 or less, preferably an integer of 4 or more and 9 or less)

  Examples of the divalent alcohol component represented by the general formula (A) include ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1, Examples include 7-heptanediol, 1,8-octanediol, and 1,9-nonanediol, and 1,6-hexanediol or 1,9-nonanediol is preferable.

  In addition, as described above, the polyester resin (in the case of including both a crystalline polyester resin and an amorphous polyester resin) is easy in that the retention rate A is 95% or more and the retention rate B is 70% or less. The total content is preferably 3% by mass or more, and more preferably 5% by mass or more. In the present application, as long as the retention ratio A and the retention ratio B are satisfied, there is no problem even if the total amount of the binder resin is a polyester resin.

(Coloring agent)
The colorant used in the toner of the exemplary embodiment may be a dye or a pigment, but a pigment is preferable from the viewpoint of light resistance and water resistance.
For example, yellow pigments such as yellow lead, zinc yellow, yellow iron oxide, cadmium yellow, chrome yellow, hansa yellow, hansa yellow 10G, benzidine yellow G, benzidine yellow GR, selenium yellow, quinoline yellow, permanent yellow NCG, etc. In particular, C.I. I. Pigment yellow 17, C.I. I. Pigment yellow 74, C.I. I. Pigment yellow 97, C.I. I. Pigment yellow 155, C.I. I. Pigment yellow 180, C.I. I. Pigment Yellow 185 or the like is preferably used.

  Magenta pigments include Bengala, Cadmium Red, Red Plum, Mercury Sulfide, Watch Young Red, Permanent Red 4R, Risor Red, Brilliantamine 3B, Brilliantamine 6B, Daypon Oil Red, Pyrazolone Red, Rhodamine B Lake, Lake Red C Pigment Red 31, 146, 147, 150, 176, 238, 269, and the like as Rose Bengal, Eoxin Red, Alizarin Lake, and Naphthol pigments. Pigments include quinacridone pigments. Examples thereof include Red 122, 202, and 209. Among these, Pigment Red 185, 238, 269, and 122 are particularly preferable from the viewpoints of manufacturability and chargeability.

  As cyan pigments, bitumen, cobalt blue, alkali blue lake, Victoria blue lake, fast sky blue, induslen blue BC, aniline blue, ultramarine blue, chalcoil blue, methylene blue chloride, phthalocyanine blue, phthalocyanine green, malachite green oxare Rate, and the like. I. Pigment blue 15: 1, C.I. I. Pigment Blue 15: 3 or the like is preferably used.

Examples of the orange pigment include red yellow lead, molybdenum orange, permanent orange GTR, pyrazolone orange, Vulcan orange, benzidine orange G, indanthrene brilliant orange RK, and indanthrene brilliant orange GK. Examples of purple pigments include manganese purple, fast violet B, and methyl violet lake. Examples of the green pigment include chromium oxide, chromium green, pigment green, malachite green lake, final yellow green G and the like.
Examples of white pigments include zinc white, titanium oxide, antimony white, and zinc sulfide.

  Examples of extender pigments include barite powder, barium carbonate, clay, silica, white carbon, talc, and alumina white. Also, acridine, xanthene, azo, benzoquinone, azine, anthraquinone, thioindico, dioxazine, thiazine, azomethine, indico, thioindico, phthalocyanine, aniline black, polymethine, triphenyl Various dyes such as methane, diphenylmethane, thiazine, thiazole, and xanthene are also used. These colorants are used alone or in combination.

  Examples of the black pigment used for the black toner include carbon black, copper oxide, manganese dioxide, aniline black, activated carbon and the like, and carbon black is particularly preferably used. Since carbon black has relatively good dispersibility, it does not require special dispersion, but is preferably produced by a production method according to the colorant.

  The content of the colorant in the electrostatic image developing toner of the present embodiment is preferably in the range of 1 part by mass to 30 parts by mass with respect to 100 parts by mass of the binder resin. It is also effective to use a surface-treated colorant or a pigment dispersant as necessary. By 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 preferably further contains a release agent.
Examples of the release agent include low molecular weight polyolefins such as polyethylene, polypropylene, and polybutene; silicones having a softening point; fatty acid amides such as oleic acid amide, erucic acid amide, ricinoleic acid amide, and stearic acid amide; carnauba wax Plant waxes such as beeswax, rice wax, candelilla wax, tree wax, jojoba oil, etc .; animal waxes such as beeswax; mineral / petroleum such as montan wax, ozokerite, ceresin wax, microcrystalline wax, Fischer-Tropsch wax Waxes: ester waxes of higher fatty acids and higher alcohols such as stearyl stearate and behenyl behenate; butyl stearate, propyl oleate, glyceryl monostearate, glyceryl distearate And ester waxes of higher fatty acids such as pentaerythritol tetrabehenate and unit price or polyhydric lower alcohols; higher fatty acids such as diethylene glycol monostearate, dipropylene glycol distearate, distearic diglyceride and tetrastearic acid triglyceride Examples include ester waxes composed of polyhydric alcohol multimers; sorbitan higher fatty acid ester waxes such as sorbitan monostearate; and cholesterol higher fatty acid ester waxes such as cholesteryl stearate.
In this embodiment, these release agents may be used alone or in combination of two or more.

As the release agent in the present embodiment, the melting temperature (main maximum endothermic peak temperature) in differential scanning calorimetry (DSC) measured according to ASTM D3418-8 is preferably 75 ° C. or higher and 100 ° C. or lower. It is more preferable that the temperature is 80 ° C. or higher and 90 ° C. or lower.
When the melting temperature is less than 75 ° C., the viscosity of the release agent becomes extremely low when emulsifying particles are fused in the toner production by the emulsion aggregation method described later, and the ratio of small particle size / high circularity toner increases, and the number particle size particles In some cases, the diameter distribution / circularity distribution cannot be set to a desired range. If the temperature exceeds 100 ° C., the change temperature of the release agent is too high, so that it does not melt sufficiently even at the time of fusion or the like, and may not be involved in controlling the particle size distribution / circularity distribution.

  From the above viewpoint, carnauba wax, rice wax, candelilla wax, paraffin wax, microcrystalline wax, polyethylene, polypropylene, and the like are used as the release agent to be used in relation to the fusion temperature at the time of manufacturing the toner described later. In particular, when a polyester resin is used as the binder resin, it is preferable to use paraffin wax, microcrystalline wax, polyethylene or the like.

  The content of the release agent in the toner is preferably 0.5% by mass or more and 15% by mass or less, and more preferably 1.0% by mass or more and 12% by mass or less. If the content of the release agent is less than 0.5% by mass, there is a risk of peeling failure particularly in oilless fixing. If the content of the release agent exceeds 15% by mass, the fluidity of the toner may deteriorate, and the image quality and the reliability of image formation may be reduced.

As described above, the toner according to the exemplary embodiment preferably uses a metal sulfate salt to control the retention rate A to 95% or more and the retention rate B to 70% or less. Thus, elemental sulfur is contained. The content of elemental sulfur in the toner is preferably 0.02% by mass or more, and more preferably 0.1% by mass or more. In view of charging properties, the content of sulfur element in the toner is preferably 2.5% by mass or less.
The sulfur element content can be determined by quantitatively analyzing the spectral intensity of fluorescent X-rays.

(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 can be added to the toner of the exemplary embodiment as necessary.
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.

  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, 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. From the viewpoint of not impairing transparency such as color developability and OHP permeability, silica particles having a refractive index smaller than that of the binder resin are preferably used. 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.

  In addition, a known material such as a charge control agent may be added to the toner. The average particle size of the material added at that time is preferably 1 μm or less, and more preferably 0.01 to 1 μm. When the average particle size exceeds 1 μm, the particle size distribution of the finally obtained electrophotographic toner may be broadened, or free particles may be generated, which may lead to a decrease in performance and reliability. On the other hand, when the average particle size is within the above range, there are no disadvantages, and the uneven distribution among the toners is reduced, the dispersion in the toners is improved, and the variation in performance and reliability is advantageous. The average particle diameter can be measured using, for example, a microtrack.

Further, the electrostatic image developing toner of this embodiment will be described in more detail along with its manufacturing method.
The method for producing the toner of this embodiment is not particularly limited, but is preferably a wet granulation method. Suitable examples of the wet granulation method include known melt suspension methods, emulsion aggregation methods, and dissolution suspension methods. Hereinafter, the emulsion aggregation method will be described as an example.

  The emulsion aggregation method is a step of forming an aggregated particle dispersion in a dispersion (hereinafter sometimes referred to as “emulsion”) in which particles containing at least a resin are dispersed (emulsified) (aggregation step). And a method of heating the aggregated particle dispersion and fusing the aggregated particles (fusion process). In addition, a step (adhesion step) of forming adhering particles by adding and mixing a particle dispersion in which particles are dispersed in the agglomerated particle dispersion and adhering the particles to the agglomerated particles between the aggregation step and the fusion step. It may be provided.

Hereinafter, a more preferable production method for producing the toner of the present embodiment will be described by taking as an example a case where a polyester resin is used as the binder resin.
A preferred toner production method in the present embodiment is such that a phase shift emulsification is performed by adding an aqueous solvent to a mixture of a binder resin including a polyester resin, a colorant, and an organic solvent, or the mixture is emulsified in an aqueous solvent. An emulsifying step of preparing a dispersion of composite particles containing a binder resin and a colorant by dispersing, an aggregating step of aggregating the composite particles and release agent particles in the dispersion into aggregated particles, A fusing step of fusing and coalescing the aggregated particles at a temperature lower than the melting temperature of the release agent.

-Emulsification process-
For example, polyester resin particles can be formed by applying a shearing force to a solution obtained by mixing an aqueous medium and a polyester resin with a disperser. At that time, particles can be formed by heating to lower the viscosity of the resin component. In addition, a dispersant may be used for stabilizing the dispersed resin particles. Furthermore, if it is oily and dissolves in a solvent with a relatively low solubility in water, the resin is dissolved in those solvents and dispersed in water together with a dispersant and a polymer electrolyte, and then the solvent is evaporated by heating or decompression. By doing so, a dispersion of polyester resin particles can be produced.

Examples of the aqueous medium include water such as distilled water and ion-exchanged water; alcohols; and the like.
Examples of the dispersant used in the emulsification step include water-soluble polymers such as polyvinyl alcohol, methyl cellulose, ethyl cellulose, hydroxyethyl cellulose, carboxymethyl cellulose, sodium polyacrylate, and sodium polymethacrylate; sodium dodecylbenzenesulfonate. Anionic surfactants such as sodium octadecyl sulfate, sodium oleate, sodium laurate, potassium stearate, cationic surfactants such as laurylamine acetate, stearylamine acetate, lauryltrimethylammonium chloride, lauryldimethylamine oxide, etc. Zwitterionic surfactant, polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene Surfactants such as nonionic surfactants down alkyl amine; and the like are; tricalcium phosphate, aluminum hydroxide, calcium sulfate, calcium carbonate, inorganic salts such as barium carbonate.

  The content of the resin particles contained in the emulsified liquid in the emulsification step is preferably in the range of 10 to 50% by mass, and more preferably in the range of 20 to 40% by mass. When the content is less than 10% by mass, the particle size distribution is widened and the toner characteristics may be deteriorated. On the other hand, if it exceeds 50% by mass, uniform stirring becomes difficult, and it may be difficult to obtain a toner having a narrow particle size distribution and uniform characteristics.

Examples of the dispersion method of the emulsion include a homogenizer, a homomixer, a pressure kneader, an extruder, a media disperser and the like as a disperser used for dispersing the emulsion.
The size of the resin particles is preferably in the range of 0.01 to 1.0 μm, more preferably 0.03 to 0.6 μm, and more preferably 0.03 to 0.4 μm in terms of the average particle size (volume average particle size). More desirable.

  As a method for dispersing the colorant, for example, a general dispersion method such as a rotary shear type homogenizer, a ball mill having media, a sand mill, or a dyno mill can be used, and the colorant is not limited at all.

  If necessary, an aqueous dispersion of these colorants can be prepared using a surfactant, or an organic solvent dispersion of these colorants can be prepared using a dispersant. Hereinafter, such a colorant dispersion may be referred to as a “colorant dispersion”. As the surfactant and dispersant used for dispersion, those according to the dispersant that can be used when dispersing the crystalline polyester resin or the like can be used.

  The addition amount of the colorant is preferably 1 to 20% by mass, more preferably 1 to 10% by mass, and more preferably 2 to 10% by mass with respect to the total amount of the polymer. More preferably, it is especially preferable to set it as the range of 2-7 mass%.

  When the colorant is mixed in the emulsification step, the polymer and the colorant can be mixed by mixing the colorant or the organic solvent dispersion of the colorant with the organic solvent solution of the polymer. .

-Aggregation process-
In the aggregation step, first, the obtained dispersion of the polyester resin particles, the colorant dispersion, and the like are mixed to obtain a mixed solution, which is heated to agglomerate at a temperature not higher than the glass transition temperature of the polyester resin. Form. Aggregated particles are formed by acidifying the pH of the mixed solution with 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 still more desirable.

As described above, in order to control the retention rate A to 95% or more and the retention rate B to 70% or less, it is preferable to use a metal sulfate salt and polyaluminum chloride when forming aggregated particles. Specifically, when mixing the composite particle dispersion, the release agent dispersion and the like, a metal sulfate metal salt and polyaluminum chloride are added and mixed.
Examples of the metal sulfate include aluminum sulfate, magnesium sulfate, potassium sulfate, sodium sulfate, calcium sulfate, and zinc sulfate. Among these, aluminum sulfate is preferable.

The amount of metal sulfate added varies depending on the type and valence of the flocculant, but is preferably 0.1% by mass or more and 5.0% by mass or less, more preferably 0.1% by mass or more and 3.0% by mass or less. .
Moreover, 0.1 mass% or more and 5.0 mass% or less are preferable, and, as for the addition amount of polyaluminum chloride, 0.1 mass% or more and 2.5 mass% or less are more preferable.

-Fusion process-
In the fusion step, the progress of aggregation is stopped by raising the pH of the suspension of aggregated particles to a range of 3 to 9 under stirring conditions in accordance with the aggregation step. The aggregated particles are fused by heating at a temperature equal to or higher than the transition temperature or the melting temperature of the crystalline polyester resin. In this case, however, the melting temperature is not higher than the melting temperature of the release agent included.

The fusing temperature is preferably set to a temperature not lower than the melting temperature of the crystalline polyester resin and lower by 5 ° C. to 10 ° C. than the melting temperature of the release agent.
The heating time may be as long as desired coalescence is achieved, and may be performed for about 0.5 to 20 hours. Thereafter, the temperature is lowered to Tg or less of the resin to solidify the particles.

  After completing the fusing step, the particles are washed and dried to obtain toner particles. Considering the chargeability of the toner, it is preferable to perform substitution cleaning with ion-exchanged water, and the degree of cleaning is generally monitored by the conductivity of the filtrate, so that the conductivity finally becomes 25 μS / cm or less. It is preferable to make it. The washing may include a step of neutralizing ions with an acid or an alkali. The treatment with an acid preferably has a pH of 4.0 or less, and the treatment with an alkali preferably has a pH of 8.0 or more. The solid-liquid separation after washing is not particularly limited, but from the viewpoint of productivity, suction filtration, pressure filtration such as a filter press, and the like are preferably used. Further, the drying method is not particularly limited, but from the viewpoint of productivity, freeze drying, flash jet drying, fluidized drying, vibration fluidized drying, etc. are preferably used, and the final toner moisture content is 1% by mass or less. More preferably, drying is performed so that the content becomes 0.7 mass% or less.

Further, the toner of this embodiment is preferably produced by a kneading and pulverizing method.
The kneading and pulverizing method is not particularly limited as long as it is a conventionally known method. Specifically, at least a kneading step of kneading the toner forming material and preparing a kneaded product, and at least crushing and classifying the kneaded product, The method includes a pulverizing and classifying step for preparing toner particles and at least an external additive mixing step for mixing an external additive with the toner particles, and further includes other steps as necessary.

  For kneading, a known uniaxial or biaxial extruder or a known uniaxial or biaxial kneader can be used. When a biaxial kneader is used, the rotational direction of the screw may be different or the same.

The kneaded product discharge temperature can be adjusted by the gap between the screw and the barrel, the screw shape, the kneading time, the screw rotation speed, the barrel temperature, and the like. A method of adding water during kneading is often used in order to lower the temperature of the kneaded product by utilizing latent heat of vaporization and increase the share.
The thus kneaded product is cooled and solidified, and then adjusted to particles having a weight average particle diameter of 5 to 9 μm through coarse crushing / crushing, crushing and classification. Examples of the pulverizer / classifier used in the present invention include a known jet type or mechanical pulverizer, a known centrifugal type or inertia type classifier.

  In the toner of this embodiment, inorganic particles and organic particles can be externally added and mixed as a fluidity aid, a cleaning aid, an abrasive, and the like. Examples of the inorganic particles include all particles usually used as external additives on the toner surface, such as silica, alumina, titanium oxide, calcium carbonate, magnesium carbonate, tricalcium phosphate, and cerium oxide. These inorganic particles preferably have a hydrophobic surface, and are used to control various toner characteristics such as chargeability, powder characteristics, and storage stability, and system suitability such as developability and transferability. It is done. As organic particles, for example, they are usually used as external additives on the surface of toner such as vinyl resins such as styrene polymers, (meth) acrylic polymers, and ethylene polymers, polyester resins, silicone resins, and fluorine resins. All particles.

  These particles are added for the purpose of improving transferability, and the primary particle size is preferably 0.01 μm to 0.5 μm. Further, a lubricant can be added. Examples of the lubricant include fatty acid amides such as ethylene bisstearyl amide and oleic acid amide, and higher alcohols such as fatty acid metal salt unilin such as zinc stearate and calcium stearate. These are generally added for the purpose of improving the cleaning property, and those having a primary particle size of 0.5 μm to 8.0 μm are used.

  Further, at least two kinds of the inorganic particles are used, and at least one kind of the inorganic particles preferably has an average primary particle diameter of 30 nm to 200 nm, more preferably 30 nm to 180 nm. As the toner particle size is reduced, non-electrostatic adhesion to the photoconductor increases, which causes transfer defects and image loss called hollow characters, and causes uneven transfer such as superimposed images. Therefore, it is preferable to add a large external additive having an average primary particle diameter of 30 nm to 200 nm to improve transferability. If the average primary particle size is smaller than 30 nm, the initial toner fluidity is good, but the non-electrostatic adhesion between the toner and the photoreceptor cannot be reduced, the transfer efficiency is lowered, This may exacerbate the density variation of the image, and the particles in the developer may be embedded in the toner surface due to stress in the developing machine over time, changing the chargeability and causing problems such as a decrease in density and fogging on the background. . On the other hand, if the average primary particle size is larger than 200 nm, the particles may be easily detached from the toner surface, and the fluidity may be deteriorated.

Specifically, silica, alumina, and titanium oxide are preferable, and it is particularly preferable to add hydrophobized silica as an essential component. It is particularly preferable to use silica and titanium oxide in combination. In addition, it is preferable to use organic particles having a particle size of 80 nm to 500 nm in order to improve transferability. Examples of the hydrophobizing agent for hydrophobizing the external additive include known materials, such as silane coupling agents, titanate coupling agents, aluminate coupling agents, and zirconium coupling agents. Examples include silicone oil and polymer coating treatment.
The external additive is adhered or fixed to the toner surface by applying a mechanical impact force with a sample mill or a Henschel mixer.

(Toner characteristics)
The number average particle size of the toner of the exemplary embodiment is preferably in the range of 3 μm to 8 μm, more preferably in the range of 3.5 μm to 7.5 μm, and in the range of 5 μm to 8 μm. Further preferred. When the number average particle size is smaller than 3 μm, the toner fluidity is lowered, the chargeability of each particle is likely to be lowered, and the charge distribution is widened, so that fogging on the background or toner spillage from the developing device is likely to occur. . On the other hand, if it is smaller than 3 μm, the cleaning property may be extremely difficult. If the number average particle diameter is larger than 8 μm, the resolution is lowered, so that sufficient image quality cannot be obtained, and it may be difficult to satisfy recent high image quality requirements.

In addition, the toner of the exemplary embodiment preferably has a shape in which the average value of the circularity (average circularity) is in the range of 0.940 to 0.980. When the average circularity is a sphere in this range, transfer efficiency and image density are improved, and high-quality image formation can be performed.
The above-mentioned number average particle diameter and average circularity are measured using a FPIA 3000 manufactured by Sysmex.

<Electrostatic image developer>
The electrostatic image developing toner of 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 dispersion type 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 include acid copolymers, straight silicone resins containing organosiloxane bonds or modified products thereof, fluororesins, polyesters, polycarbonates, phenol resins, epoxy resins, etc., but are not limited thereto. Absent.

  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 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 the exemplary embodiment and the carrier in the two-component developer is preferably in the range of toner: carrier = 1: 100 to 30: 100, preferably about 3: 100 to 20: 100. A range is more preferred.

<Image forming apparatus>
Next, the image forming apparatus of this embodiment using the electrostatic image developer of this embodiment described above will be described.
The image forming apparatus according to the present embodiment includes an image carrier, a developing unit that develops an electrostatic image formed on the image carrier as a toner image with a developer, and a toner image formed on the image carrier. The electrostatic charge image developer according to the present embodiment described above as the developer, and a transfer means for transferring onto a recording medium such as paper and a fixing means for fixing the toner image transferred onto the recording medium Is used.

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 of the present embodiment is preferably used that includes at least the electrostatic charge image developer.
Hereinafter, although an example of the image forming apparatus of this embodiment is shown, it is not necessarily limited to this. In addition, the main part shown to a figure is demonstrated and the description is abbreviate | omitted about others.

  FIG. 1 is a schematic diagram showing a quadruple tandem full-color image forming apparatus. The image forming apparatus shown in FIG. 1 is a first to first electrophotographic method 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 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. It is designed to travel in the direction toward 10K. The support roller 24 is biased in a direction away from the drive roller 22 by a spring or the like (not shown), and a predetermined tension is applied to the intermediate transfer belt 20 wound around 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 includes 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 unit that forms a yellow image disposed on the upstream side in the intermediate transfer belt traveling direction. 10Y will be described as a representative. Note that the second to fourth units are denoted by reference numerals with magenta (M), cyan (C), and black (K) instead of yellow (Y) in the same parts as the first unit 10Y. Description of 10M, 10C, 10K is omitted.

The first unit 10Y has a photoreceptor 1Y that functions as an image holding member. Around the photoreceptor 1Y, an electrostatic charge image is formed by exposing the surface of the photoreceptor 1Y to a predetermined potential with a charging roller 2Y and the charged surface with a laser beam 3Y based on the color-separated image signal. An exposure device 3; a developing device (developing means) 4Y for supplying the charged toner to the electrostatic image and developing the electrostatic image; a primary transfer roller 5Y (primary) for transferring the developed toner image onto the intermediate transfer belt 20; A 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.
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 the operation, the surface of the photoreceptor 1Y is charged to a potential of about −600V to −800V by the charging roller 2Y.
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 charge 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.

  Yellow toner is accommodated in the developing device 4Y. 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.

The cleaning device (cleaning means) 6Y has a configuration in which residual toner on the surface of the photoreceptor 1Y is processed by a rotating brush (cleaning brush) 11Y and scraped by the cleaning blade 12Y (the cleaning devices 6M, 6C, and 6K have the same configuration). is there.).
In the image forming apparatus of this embodiment, it is preferable that the cleaning unit has at least a rotating brush from the viewpoint of more efficiently suppressing the occurrence of filming. As shown in FIG. It is more preferable to have both of the cleaning blades.

As the material of the rotating brush 11Y, a known material can be used. Among them, nylon, acrylic or polypropylene is preferable, and among these, nylon is particularly preferable because of excellent long-term stability. The fiber thickness of the brush surface is preferably in the range of 2 to 17 denier, more preferably in the range of 3 to 10 denier. By setting the fiber thickness within the above range, the toner can be efficiently removed from the surface of the photoreceptor.
In the image forming apparatus of this embodiment, the cleaning unit preferably has at least a rotating brush, and more preferably has both a rotating brush and a cleaning blade as shown in FIG.

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 intermediate transfer belt 20 onto which the four color toner images have been transferred in multiple layers through the first to fourth units is disposed 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, a recording sheet (recording medium) 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 supplied to the support 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 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. 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.

<Process cartridge, toner cartridge>
FIG. 2 is a schematic configuration diagram showing a preferred example of a process cartridge containing the electrostatic charge image developer according to the present embodiment. The process cartridge 200 includes a charging roller 108, a developing device (developing unit) 111, a photoconductor cleaning device (cleaning unit) 113, an opening 118 for exposure, and static elimination exposure, along with the photoconductor (image holding member) 107. The opening 117 is combined and integrated using the mounting rail 116.
The process cartridge 200 is detachable from an image forming apparatus main body including a transfer device 112, a fixing device 115, and other components (not shown). It forms a forming apparatus. Reference numeral 300 denotes a recording sheet.

The process cartridge shown in FIG. 2 includes a charging device 108, a developing device 111, a cleaning device (cleaning means) 113, an opening 118 for exposure, and an opening 117 for static elimination exposure. Can be selectively combined. In the process cartridge according to the present embodiment, in addition to the photosensitive member 107, the charging device 108, the developing device 111, the cleaning device (cleaning means) 113, the opening 118 for exposure, and the opening 117 for static elimination exposure. At least one selected from the group consisting of: The cleaning device 113 has a configuration in which residual toner on the surface of the photoconductor 107 is processed with a rotating brush (cleaning brush) 121 and scraped off with a cleaning blade 122. In the image forming apparatus of this embodiment, the cleaning unit preferably has at least a rotating brush, and more preferably has both a rotating brush and a cleaning blade as shown in FIG.

  Next, the toner cartridge of this embodiment will be described. The toner cartridge according to this 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. It is a toner of the invention. The toner cartridge of the present invention only needs to contain at least toner, and may contain developer, for example, depending on the mechanism of the image forming apparatus.

  Therefore, in an image forming apparatus having a configuration in which a toner cartridge can be attached and detached, the storage stability can be maintained even in a toner cartridge whose container is miniaturized by using the toner cartridge containing the toner of the present invention. 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.

Hereinafter, although an example and a comparative example are given and the present invention is explained more concretely in detail, the present invention is not limited to the following examples. In the following description, “part” represents “part by mass” and “%” represents “% by mass” unless otherwise specified. However, Example 5 is a reference example.

First, a method for measuring physical property values in this example will be described.
(1) Measurement of molecular weight Molecular weight distribution was performed on condition of the following. Tosoh Corporation HLC-8120GPC, SC-8020 apparatus was used, TSK geli, SuperHM-H (6.0 mmID × 15 cm × 2) was used as a column, and THF (tetrahydrofuran) was used as an eluent. As experimental conditions, the sample concentration was 0.5%, and the flow rate was 0.6 ml / min. Sample injection volume 10 μl, measurement temperature 40 ° C., calibration curve is A-500, F-1, F-10, F-80, F-380, A-2500, F-4, F-40, F-128, Made from 10 samples of F-700. The data collection interval in sample analysis was 300 ms.

(2) Measurement of toner particle size For measurement of toner particle size and particle size distribution, a Coulter Counter TA-II type (manufactured by Beckman Coulter Co.) is used as a measuring device, and an electrolyte is ISOTON-II (manufactured by Beckman Coulter Co.). used.
As a measurement method, 0.5 to 50 mg of a measurement sample is added to 2 ml of a 5% by weight aqueous solution of a surfactant as a dispersant, preferably sodium alkylbenzenesulfonate. This was added to 100 to 150 ml of the electrolytic solution. The electrolytic solution in which the sample is suspended is subjected to a dispersion treatment with an ultrasonic disperser for about 1 minute, and the particle size distribution of particles of 2 to 60 μm is measured using the Coulter counter TA-II with an aperture diameter of 100 μm. The volume average particle diameter D50v was determined as described above. The number of particles to be measured was 50,000.

(3) Measurement of Volume Average Particle Size of Resin Fine Particles, Colorant Particles, etc. Measured using a laser diffraction / scattering type particle size distribution analyzer (LS Particle Size Analyzer: LS13 320, manufactured by BECKMAN COULTER). For the particle size range (channel) obtained by dividing the obtained particle size distribution, the volume cumulative distribution is subtracted from the small particle size side, and the particle size that becomes 50% cumulative is defined as the volume average particle size d.

(4) Measurement of glass transition temperature The glass transition temperature (Tg) of the binder resin is measured using a differential scanning calorimeter (manufactured by Shimadzu Corporation: DSC-50) under conditions of a heating rate of 3 ° C./min. Was determined by The glass transition temperature was the temperature at the intersection of the extended line of the base line and the rising line in the endothermic part.

(Production of toner)
[Preparation of resin particle dispersion A]
-Dimethyl terephthalate: 150 parts-Dimethyl fumarate: 15 parts-Trimellitic anhydride: 20 parts-Bisphenol A propylene oxide 2 mol adduct: 240 parts-Ethylene glycol: 19 parts Stirrer, thermometer, condenser -After putting into a reaction vessel equipped with a nitrogen gas introduction tube and replacing the reaction vessel with dry nitrogen gas, 2.4 parts of dibutyltin oxide was added as a catalyst, and the mixture was stirred at about 195 ° C for about 6 hours under a nitrogen gas stream. After the reaction, the temperature is further raised to about 240 ° C., and the reaction is stirred for about 6 hours. Then, the inside of the reaction vessel is decompressed to 10.0 mmHg, and the reaction is stirred for 0.5 hours under reduced pressure. A was obtained.
Subsequently, the obtained resin A was dispersed using a disperser in which Cavitron CD1010 (manufactured by Eurotech Co., Ltd.) was modified to a high temperature and high pressure type. The composition ratio of ion exchange water 80%, polyester resin concentration 20%, pH adjusted to 8.0 with ammonia, rotor rotation speed 60 Hz, pressure 5 kg / cm ² , heating by heat exchanger 140 ° C. The Cavitron was operated under the conditions to obtain a resin particle dispersion A containing 20% solids polyester. Table 1 shows the weight average molecular weight of the obtained resin A, the glass transition temperature, and the volume average particle diameter of the resin particle dispersion A.

[Preparation of resin particle dispersion B]
・ Dimethyl terephthalate: 135 parts ・ Dimethyl fumarate: 45 parts ・ Bisphenol A propylene oxide 2 mol adduct: 290 parts ・ Ethylene glycol: 10 parts The above components are stirred, a thermometer, a condenser, and a reaction equipped with a nitrogen gas introduction pipe After putting into the container and substituting the inside of the reaction container with dry nitrogen gas, 2.7 parts of dibutyltin oxide was added as a catalyst, and then synthesized in the same manner as Resin A to obtain Resin B which is a pale yellow transparent polyester. .
Next, the resin B was dispersed in the same manner as the resin particle dispersion A to obtain a resin particle dispersion B. Table 1 shows the weight average molecular weight of the obtained resin B, the glass transition temperature, and the volume average particle diameter of the resin particle dispersion B.

[Preparation of resin particle dispersion C]
-Dimethyl terephthalate: 125 parts-Dodecenyl succinic anhydride: 65 parts-Trimellitic anhydride: 19 parts-Bisphenol A ethylene oxide 2 mol adduct: 45 parts-Bisphenol A propylene oxide 2 mol adduct: 290 parts Was put into a reaction vessel equipped with a thermometer, thermometer, condenser, and nitrogen gas inlet tube, and the reaction vessel was replaced with dry nitrogen gas, and then 2.7 parts of dibutyltin oxide was added as a catalyst and synthesized in the same manner as Resin A. Resin C, which is a yellow transparent polyester, was obtained.
Next, the resin C was dispersed in the same manner as the resin particle dispersion A to obtain a resin particle dispersion C. Table 1 shows the weight average molecular weight of the obtained resin C, the glass transition temperature, and the volume average particle diameter of the resin particle dispersion C.

[Preparation of resin particle dispersion D]
・ Dimethyl dodecanoate: 205 parts ・ Dimethyl sebacate: 45 parts ・ 1,9-nonanediol: 160 parts The above components were put into a reaction vessel equipped with a stirrer, thermometer, condenser, and nitrogen gas inlet tube to react. After the inside of the container was replaced with dry nitrogen gas, 1.7 parts of titanium tetrabutoxide was added as a catalyst, and thereafter synthesized in the same manner as the polyester resin particles A to obtain a resin D which is a white transparent polyester.
Subsequently, resin D was dispersed in the same manner as resin A to obtain resin particle dispersion D. Table 1 shows the weight average molecular weight of the obtained resin D, the glass transition temperature, and the volume average particle diameter of the resin particle dispersion D.

[Preparation of resin particle dispersion E]
-Dimethyl terephthalate: 130 parts-Dodecenyl succinic anhydride: 65 parts-Trimellitic anhydride: 13 parts-Bisphenol A ethylene oxide 2 mol adduct: 110 parts-Bisphenol A ethylene oxide 2 mol adduct: 220 parts Was put into a reaction vessel equipped with a thermometer, thermometer, condenser, and nitrogen gas inlet tube, and the reaction vessel was replaced with dry nitrogen gas, and then 2.7 parts of dibutyltin oxide was added as a catalyst and synthesized in the same manner as Resin A. Resin E which is yellow transparent polyester was obtained.
Subsequently, the resin E was dispersed in the same manner as the resin particle dispersion A to obtain a resin particle dispersion E. Table 1 shows the weight average molecular weight of the obtained resin E, the glass transition temperature, and the volume average particle diameter of the resin particle dispersion E.

[Preparation of resin particle dispersion F]
-Dimethyl terephthalate: 145 parts-Dimethyl fumarate: 35 parts-Bisphenol A ethylene oxide 2 mol adduct: 95 parts-Bisphenol A propylene oxide 2 mol adduct: 240 parts The above ingredients are stirred, thermometer, condenser, nitrogen gas introduced A reaction vessel equipped with a tube, the inside of the reaction vessel was replaced with dry nitrogen gas, 3.3 parts of dibutyltin oxide was added as a catalyst, and then synthesized in the same manner as the resin A. F was obtained.
Next, the resin F was dispersed in the same manner as the resin particle dispersion A to obtain a resin particle dispersion F. Table 1 shows the weight average molecular weight of the obtained resin F, the glass transition temperature, and the volume average particle diameter of the resin particle dispersion F.

[Preparation of resin particle dispersion G]
-Styrene: 296 parts-n-butyl acrylate: 104 parts-Acrylic acid: 6 parts-Dodecanethiol: 10 parts-Divinyl adipate: 1.8 parts (above, manufactured by Wako Pure Chemical Industries, Ltd.)
12 parts of nonionic surfactant (Sanyo Kasei Co., Ltd .: Nonipol 400) and anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen SC) 8 parts Is added to a solution dissolved in 610 parts of ion-exchanged water, dispersed in a flask, emulsified, and slowly mixed for 10 minutes, while ion-exchanged water in which 8 parts of ammonium persulfate (manufactured by Wako Pure Chemical Industries, Ltd.) is dissolved. 50 parts were added and nitrogen substitution was performed at 0.1 liter / min for 20 minutes. Thereafter, the contents in the flask were heated in an oil bath until the contents reached 73 ° C. while stirring, and emulsion polymerization was continued for 5 hours to prepare a resin particle dispersion G containing resin G having a solid content of 40%. Table 1 shows the weight average molecular weight of the obtained resin G, the glass transition temperature, and the volume average particle diameter of the resin particle dispersion G.

[Preparation of release agent dispersion]
Paraffin wax HNP9 (melting point: 74 ° C., manufactured by Nippon Seiwa Co., Ltd.): 45 parts Anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd., Neogen RK): 5 parts Ion-exchanged water: 200 parts A mold release agent having a volume average particle diameter of 210 nm is heated to ℃ and dispersed using a homogenizer (manufactured by IKA, Ultra Turrax T50), and then dispersed by a pressure discharge type gorin homogenizer (Gorin). A dispersed release agent dispersion (release agent concentration: 20%) was prepared.

[Preparation of colorant dispersion]
-Cyan pigment (manufactured by Dainichi Seika Co., Ltd., Pigment Blue 15: 3 (copper phthalocyanine)): 1000 parts-Anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd., Neogen R): 150 parts-Ion-exchanged water: 9000 Part A colorant obtained by mixing and dissolving the above components and dispersing the colorant (cyan pigment) by dispersing for about 1 hour using a high-pressure impact disperser ultimateizer (manufactured by Sugino Machine Co., Ltd., HJP30006). A dispersion was prepared. The volume average particle size of the colorant (cyan pigment) in the colorant dispersion was 0.15 μm, and the colorant particle concentration was 23%.

[Production of toner]
In a round stainless steel flask, the materials shown in Table 2 (resin particle dispersions A to G, release agent dispersion, and colorant dispersion) were added in amounts shown in Table 2, and a homogenizer (manufactured by IKA: Ultra). Mix and disperse with Thalax T50). Next, 10% aqueous solution of aluminum sulfate and 1% aqueous solution of polyaluminum chloride as a flocculant were added thereto in amounts shown in Table 2, respectively, and the dispersion operation was continued with an ultra turrax.
While installing a stirrer and a mantle heater and adjusting the number of revolutions of the stirrer so that the slurry can be sufficiently stirred, the temperature was raised to 40 ° C. at 0.5 ° C./min, held at 40 ° C. for 15 minutes, then 0 The particle size was measured with a Coulter counter [TA-II] type (aperture diameter: 100 μm, manufactured by Coulter, Inc.) every 10 minutes while raising the temperature at 05 ° C./min, and the volume average particle size was 5.2 μm. Then, as the additional resin dispersions (resin particle dispersions A to G), the additional resin particle dispersions (resin particle dispersions A to G) shown in Table 2 were respectively added over 3 minutes. After holding for 30 minutes, the pH was adjusted to 8.0 using a 5% by mass aqueous sodium hydroxide solution, and aggregation was stopped.

Then, it heated up to 90 degreeC with the temperature increase rate of 1 degree-C / min, and hold | maintained at 90 degreeC. The particle shape and surface properties were observed every 30 minutes with an optical microscope and a scanning electron microscope (FE-SEM), and after the aggregated particles were sufficiently fused, the particles were cooled with ice water to immobilize the particles. The product was filtered, washed with ion exchange water, and then dried using a vacuum dryer to obtain a toner. Table 3 shows the volume average particle diameter of the obtained toner.
To 100 parts of the obtained toner, 1 part of hydrophobic silica particles (manufactured by Nippon Aerosil Co., Ltd., RY-50) and 0.8 part of hydrophobic titanium oxide particles are added, and externally added and mixed with a Henschel mixer to obtain an electrostatic charge. Image developing toners A to G (toners A to G) were obtained. Further, with respect to the toners A to G, the volume average particle diameter, the initial weight average molecular weight (A1 and B1), the A2 and B2, the retention rate A, the retention rate B, and the sulfur element content are described above. Each was measured by the method. The results are shown in Table 3.

Polyester resin D: 20 parts Polyester resin E: 156 parts Carbon black (manufactured by Cabot: Mogal L): 6 parts Polyethylene wax (Toyo Petrolite, Polywax 725): 50 parts The above composition is powdered with a Henschel mixer The mixture was melt-kneaded with an extruder (set temperature 105 ° C.), cooled, coarsely pulverized, finely pulverized, and classified to obtain a toner. Table 3 shows the volume average particle diameter of the obtained toner.
To 100 parts of the obtained toner, 1 part of hydrophobic silica particles (manufactured by Nippon Aerosil Co., Ltd., RY-50) and 0.8 part of hydrophobic titanium oxide particles are added, and externally added and mixed with a Henschel mixer to obtain an electrostatic charge. Image developing toner H (toner H) was obtained. Further, the volume average particle diameter, initial weight average molecular weight (A1, B1), A2, B2, retention rate A, retention rate B, and sulfur element content of the toner H are determined by the method described above. Each was measured. The results are shown in Table 3.

(Preparation of electrostatic charge image developer)
To a carbon dispersion obtained by mixing 1.25 parts of toluene with 0.10 parts of carbon black (trade name; VXC-72, manufactured by Cabot Corporation) and stirring and dispersing in a sand mill for 20 minutes, a trifunctional isocyanate 80% ethyl acetate solution ( Takenate D110N, manufactured by Takeda Pharmaceutical Co., Ltd.) 1.25 parts of the coating agent resin solution mixed with stirring and Mn-Mg-Sr ferrite particles (volume average particle size: 35 μm; EF-35B manufactured by Powdertech Co., Ltd.) The mixture was put into a kneader, mixed and stirred at 25 ° C. for 5 minutes, and then heated to 150 ° C. at normal pressure to distill off the solvent. After further 30 minutes of mixing and stirring, the heater was turned off and the temperature was lowered to 50 ° C. The obtained coated carrier was sieved with a 75 μm mesh to prepare a carrier.
In a V blender, 95 parts of the carrier and 5 parts of each of the toners A to H were mixed to obtain electrostatic image developers A to H (developers A to H), respectively.

<Examples 1-5, Comparative Examples 1-3>
(Filming evaluation)
Each of the developers A to H was subjected to printing evaluation using a modified machine of a color copying machine “DocuCenter-II C7500” manufactured by Fuji Xerox Co., Ltd. The results are shown in Table 4. The remodeling is performed even when the developer is contained only in a single developing machine. In addition, as in the image forming apparatus shown in FIG. 1, the cleaning device 6 (Y to K) includes a rotating brush (11Y to 11K) in order from the upstream side in the rotation direction of the photoconductor (1Y to 1K). And a cleaning blade (12Y to 12K).

Evaluation was made after each developer was added, and a high-humidity environment (32 ° C., 90% RH) was used to create an image pattern in which a belt-like image with an image density of 5% was formed in the process direction, and 10000 sheets were printed continuously. Went. After printing, A3 full-screen halftone (image density 40%) was collected and image quality evaluation was performed (initial and after printing 10,000 sheets). Further, the photoconductor was taken out from the modified machine, and the filming state on the surface of the photoconductor was visually observed from the difference in reflectance, and evaluated according to the following criteria (initial and after printing 10,000 sheets).
(Double-circle): There is no problem on image quality, and the film is uniform on the photosensitive member and no filming is observed.
○: Although there is no problem in image quality, thin filming (gloss difference) matching the image pattern is generated on the photosensitive member, but it is within an allowable range.
(Triangle | delta): On the image quality, the band-like lightness and the light / dark difference have arisen. Filming can be clearly confirmed on the photoconductor, which is an unacceptable level.
X: There is a clear and light difference in image quality, and clear filming occurs on the photoreceptor. This is an unacceptable level.

(Deinking evaluation)
Each developer A to H was used in a film copying evaluation using a remodeled machine of a color copying machine “DocuCenter-II C7500” manufactured by Fuji Xerox Co., Ltd. A test paper was prepared by forming an image for testing on the surface of 75 g / m ² paper. Using this test paper, a handsheet for evaluation was prepared under the following conditions.
(1) Image disaggregation: A test paper was put into a beaker containing an aqueous dispersion having the following composition, and stirred at 50 ° C. for 20 minutes to disaggregate the image.
Test paper: 5.0%
NaOH: 0.7%
Sodium silicate: 3.0%
H ₂ O ₂ : 1.0%
Deinking agent (Liptor S2800; manufactured by Lion Corporation): 0.2%

(2) Dilution / Dehydration / Kneader treatment: Add the test paper of (1), add water to the stirred aqueous dispersion and dilute to 5%, then spin-dry, further 20% pulp, sodium silicate 3 Pulp and sodium silicate were added to 0.0% and NaOH 0.5%, and the mixture was disaggregated with a kneader.
(3) Aging: The kneader disaggregated material was aged at 50 ° C. for 2 hours.
Flotation: Water is added to the aged product to prepare a dispersion with a pulp concentration of 1%, fine bubbles are released into the dispersion for 7 minutes, and the toner in the liquid is adsorbed by the bubbles and floats on the surface of the water. Isolate.
(4) Washing: 2.4 g of deinked pulp is washed twice with 1 liter of water each time.
(5) Production of hand-made sheet for test: A hand-made sheet (basis weight 100 g / m ² ) was produced by a tapi sheet machine.

In the deinking property evaluation, the number of toners present in 9 cm ² of the obtained handsheet was measured visually and under a microscope with a number of 100 μm or more (visible size) and a number of 60 to 100 μm. The results are shown in Table 4.
When the number of toners of 100 μm or more is 15 or less and the number of toners of 60 to 100 μm is 20 or less, the deinking property is at a level that causes no practical problem.

<Example 6>
In Example 1, the cleaning device 6 (Y to K) in the modified machine of “DocuCentre-II C7500” has only the rotating brushes (11Y to 11K) installed, and no cleaning blade (12Y to 12K) installed. Evaluation similar to Example 1 was implemented except having changed into. The results are shown in Table 4.

<Example 7>
In Example 1, the cleaning device 6 (Y to K) in the modified machine of “DocuCentre-II C7500” is provided with only the cleaning blade (12Y to 12K) and not the rotating brush (11Y to 11K). Evaluation similar to Example 1 was implemented except having changed into. The results are shown in Table 4.

1 is a schematic configuration diagram illustrating an example of an image forming apparatus according to an embodiment. It is a schematic block diagram which shows an example of the process cartridge of embodiment.

Explanation of symbols

1Y, 1M, 1C, 1K, 107 photoconductor (image carrier)
2Y, 2M, 2C, 2K, 108 Charging roller 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 (recording medium)

Claims (9)

The retention A of the weight average molecular weight measured for tetrahydrofuran solubles when held in water at pH 8 for 1 hour at 90 ° C. is 95% or more, and soluble in tetrahydrofuran when held in water at pH 9 at 98 ° C. for 1 hour. retention B is der 70% or less of the measured weight average molecular weight for the amount is,
A resin particle dispersion and a colorant dispersion are mixed, and an aggregated particle forming step of forming aggregated particles using a metal sulfate salt and polyaluminum chloride, and the aggregation is performed by heating to a temperature equal to or higher than the glass transition temperature of the resin particles. Produced through fusion, coalescence of particles, coalescence,
A toner for developing an electrostatic charge image, comprising an amorphous polyester resin . The non-crystalline polyester resin, as the alcohol component constituting the resin, according to claim 1, characterized by containing a divalent alcohol component represented by the following general formula (A) or 20 mol% of the total alcohol component Toner for developing electrostatic images.
Formula (A)
HO— (CH ₂ ) _x —OH
(In general formula (A), x represents an integer of 2 or more and 9 or less.) The toner according to claim 1 or claim 2, wherein the content of the polyester resin contained in the toner for developing electrostatic images is 3 mass% or more. The toner for developing an electrostatic charge image according to any one of claims 1 to 3 , which contains 0.02% or more of elemental sulfur. It includes a toner, electrostatic image developer, which is a toner for electrostatic image development according to any one of the toners according to claim 1 to claim 4. A toner cartridge containing at least toner, wherein the toner is the electrostatic image developing toner according to any one of claims 1 to 4 . A process cartridge comprising at least a developer holder and containing the electrostatic charge image developer according to claim 5 . An image carrier, a developing unit that develops the electrostatic image formed on the image carrier as a toner image with a developer, and a transfer unit that transfers the toner image formed on the image carrier onto a recording medium. 6. An electrostatic charge according to claim 5 , further comprising: a fixing unit that fixes the toner image transferred onto the recording medium; and a cleaning unit that cleans residual toner on the image holding member after transfer. An image forming apparatus which is an image developer. The image forming apparatus according to claim 8 , wherein the cleaning unit includes a rotating brush.

Images