JP2014016536A - Method for producing black toner for developing electrostatic charge image - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a black toner for developing an electrostatic charge image, the black toner having good fluidity and heat-resistant storage property and exhibiting excellent image density, and to provide a method for producing the black toner.SOLUTION: A method for producing a black toner for developing an electrostatic charge image includes the following steps (1) to (3): step (1) of aggregating resin particles (A) containing an amorphous polyester (a), carbon black and copper phthalocyanine having an anionic group in an aqueous medium to obtain aggregated particles (1); step (2) of aggregating resin particles (C) containing an amorphous polyester (c) on the surfaces of the aggregated particles (1) to obtain aggregated particles (2); and step (3) of holding the aggregated particles (2) at a temperature equal to or higher than the glass transition temperature of the amorphous polyester (c) to obtain core-shell particles in which resin particles (C) are fused with each other.

Description

  The present invention relates to a black toner for developing an electrostatic image and a method for producing the same.

In the field of electrophotography, with the development of an electrophotographic system, development of toner for electrophotography corresponding to higher image quality and higher speed is required.
Attempts have been made to use a mixture of a plurality of resins in order to improve thermal characteristics and color characteristics in response to higher image quality and higher speed. Attempts have also been made to use a plurality of colorants in combination.

For example, in Patent Document 1, as an attempt to mix a plurality of resins, for the purpose of improving low-temperature fixability and storage stability, (1) a resin particle dispersion containing amorphous polyester and crystalline polyester An electrophotography in which the resin particles inside are agglomerated and held in a specific temperature range for 0.5 to 7 hours to obtain a coalescent particle dispersion, and further held in a specific temperature range below 1 to 48 hours A method for producing a toner is disclosed.
In Patent Document 2, as an attempt to use a plurality of colorants in combination, the colorant is a black pigment for the purpose of improving bluishness, granulation properties, offset properties, chargeability, storage stability, color development properties, and OHP permeability. Is a mixed pigment of carbon black and cyan phthalocyanine copper phthalocyanine, and is used in a masterbatch kneaded with a resin that forms part of the binder resin, and is produced in an aqueous medium for developing electrostatic images. Toner is disclosed.

JP 2010-276719 A JP 2008-3360 A

The toner for electrophotography needs to have high fluidity in order to improve transportability during supply and recovery during development. In order to improve the fluidity, the shape is made close to spherical by heating at the time of producing the toner or by blending a relatively large amount of a relatively soft resin. However, the toner obtained in this manner has a problem that heat resistant storage stability, which is stability at high temperature storage, is lowered. In addition, black pigments that require clear printability such as letters require a higher image density than other colors, but there is also a problem that the image density decreases by blending a large amount of resin, For example, a conventional toner such as the toner of Patent Document 2 is insufficient in terms of making these compatible.
An object of the present invention is to provide a black toner for developing an electrostatic image having excellent fluidity and heat-resistant storage stability and excellent image density, and a method for producing the same.

  The present inventors have considered that the factors affecting the fluidity, heat-resistant storage stability, and image density are in the state of the resin and pigment at the time of manufacturing the black toner. As a result, in the production of core-shell type toners, it contains amorphous polyester, carbon black and specific phthalocyanine compound in the core part, and uses amorphous polyester in the shell part, so it has good fluidity and heat resistant storage stability. It was found that a black toner for developing an electrostatic charge image having excellent image density can be obtained.

That is, the present invention provides the following [1] and [2].
[1] A method for producing a black toner for developing an electrostatic charge image, comprising the following steps (1) to (3):
Step (1): A step of obtaining aggregated particles (1) by aggregating resin particles (A) containing amorphous polyester (a), carbon black, and copper phthalocyanine having an anionic group in an aqueous medium. Step (2): Step of obtaining aggregated particles (2) by aggregating resin particles (C) containing amorphous polyester (c) on the surface of aggregated particles (1) Step (3): Aggregated particles (2 ) Above the glass transition point of the amorphous polyester (c) to obtain core-shell particles in which the resin particles (C) are fused to each other, the electrostatic charge image obtained by the production method of [2] [1] Black toner for development.

  According to the present invention, it is possible to provide an electrostatic image developing black toner having good fluidity and heat-resistant storage stability and excellent image density, and a method for producing the same.

The method for producing a black toner for developing an electrostatic charge image of the present invention includes the following steps (1) to (3). In the present specification, the black toner for developing an electrostatic image is sometimes referred to as “black toner”.
Step (1): A step of obtaining aggregated particles (1) by aggregating resin particles (A) containing amorphous polyester (a), carbon black, and copper phthalocyanine having an anionic group in an aqueous medium. Step (2): Step of aggregating resin particles (C) containing amorphous polyester (c) to aggregated particles (1) to obtain aggregated particles (2) Step (3): Aggregated particles (2) The step of obtaining fused core-shell particles that are held above the glass transition point of the amorphous polyester (c) and the above step (1) is a release agent particle containing a release agent together with the resin particles (A). The step of agglomerating particles to obtain aggregated particles (1) is preferred. Moreover, it is preferable that the resin particle (A) contains crystalline polyester (b).

The reason why the black toner for developing an electrostatic charge image obtained by the production method of the present invention has good fluidity and heat-resistant storage stability and excellent image density is not clear, but is considered as follows.
In the present invention, the resin particles (A) contain amorphous polyester (a), carbon black, and copper phthalocyanine having an anionic group. Carbon black is bulky, acts as a filler, and it is considered that the surface of carbon black having a polar portion is easily exposed to the resin particle surface in an aqueous medium. For this reason, it is considered that homogeneous aggregation and sufficient fusion are not easily performed even in the aggregation and fusing process, and the toner has severe surface irregularities, resulting in a decrease in fluidity and heat-resistant storage stability. However, in the present invention, the copper phthalocyanine having an anionic group is adsorbed on the polar surface of the carbon black, so that the carbon black is dispersed in the resin and tends to stay inside the resin particle. Exposure is prevented or suppressed. As a result, the obtained toner is considered to have a smooth surface and excellent fluidity and heat-resistant storage stability.
Further, since the localization of carbon black on the particle surface as described above can be prevented, it is considered that a fine dispersion state can be maintained in the resin, and the image density is also considered to be excellent.
Hereafter, each component, process, etc. used for this invention are demonstrated.

[Amorphous polyester (a)]
In the present invention, the amorphous polyester means the ratio of the softening point to the maximum endothermic peak temperature by a differential scanning calorimeter (DSC), (softening point (° C.)) / (Maximum endothermic peak temperature (° C.)). A resin having a defined crystallinity index greater than 1.4 or less than 0.6.
The black toner of the present invention has an amorphous polyester (a) in the core portion from the viewpoint of improving the adhesion with the shell portion and improving the heat-resistant storage stability and finely dispersing the pigment and improving the image density. Containing.

  The amorphous polyester (a) can be produced by subjecting an acid component and an alcohol component to a polycondensation reaction. A catalyst is preferably used in the polycondensation reaction.

Examples of the acid component of the amorphous polyester (a) include dicarboxylic acids and trivalent or higher polyvalent carboxylic acids from the viewpoint of improving toner image density and low-temperature fixability. Among them, dicarboxylic acids are preferable. More preferably, a dicarboxylic acid and a trivalent or higher polyvalent carboxylic acid are used in combination. In the present specification, the acid component includes not only a free acid but also an anhydride that decomposes during the reaction to produce an acid, and an alkyl ester having 1 to 3 carbon atoms.
The dicarboxylic acid is preferably at least one selected from aliphatic dicarboxylic acids and aromatic dicarboxylic acids. From the viewpoint of improving compatibility with the crystalline polyester, and further improving the image density and low-temperature fixability of the toner, It is more preferable to contain a group dicarboxylic acid.
An aliphatic dicarboxylic acid is an alkyl succinic acid having an alkyl group having 9 to 14 carbon atoms, an alkenyl succinic acid having an alkenyl group having 9 to 14 carbon atoms, and an alkyl group from the viewpoint of improving low-temperature fixability and image density of the toner. At least one selected from aliphatic dicarboxylic acids having 2 to 12 carbon atoms other than succinic acid and alkenyl succinic acid is preferable. The aliphatic dicarboxylic acid having 2 to 12 carbon atoms is more preferably 2 to 6 carbon atoms.
Examples of the aliphatic dicarboxylic acid having 2 to 12 carbon atoms include oxalic acid, malonic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, succinic acid, adipic acid, sebacic acid, and 1,12-dodecanedioic acid. Examples include at least one selected from acids, and fumaric acid is preferred from the viewpoint of improving the low-temperature fixability and heat-resistant storage stability of the toner.

Among the alkyl succinic acids having an alkyl group having 9 to 14 carbon atoms and the alkenyl succinic acid having an alkenyl group having 9 to 14 carbon atoms, from the viewpoint of increasing the affinity with the crystalline polyester and thus improving the low-temperature fixability of the toner. Alkenyl succinic acid having an alkenyl group having 9 to 14 carbon atoms is preferred.
Further, from the viewpoint of enhancing the affinity with the crystalline polyester and thus enhancing the low-temperature fixability of the toner, the alkyl group or alkenyl group preferably has 10 to 14 carbon atoms, more preferably 12 to 14 carbon atoms.
Specific examples of the alkyl succinic acid having an alkyl group having 9 to 14 carbon atoms and the alkenyl succinic acid having an alkenyl group having 9 to 14 carbon atoms include at least one selected from dodecyl succinic acid, dodecenyl succinic acid and octenyl succinic acid. In view of improving the low-temperature fixability of the toner, dodecenyl succinic acid is preferable.
The alkyl group and alkenyl group of the alkyl succinic acid having an alkyl group having 9 to 14 carbon atoms and the alkenyl succinic acid having an alkenyl group having 9 to 14 carbon atoms are preferably a branched alkyl group and a branched alkenyl group.
The branched structure may exist in any part of the alkyl group and the alkenyl group, but a mixture having a plurality of branched structures is preferable from the viewpoint of enhancing the compatibility with the crystalline polyester.
The acid component preferably further contains an aromatic dicarboxylic acid, and the aromatic dicarboxylic acid is preferably terephthalic acid.

  Examples of the trivalent to pentavalent aromatic carboxylic acid include at least one selected from trimellitic acid, 2,5,7-naphthalenetricarboxylic acid, and pyromellitic acid. Among them, the viewpoint of improving the heat resistant storage stability of the toner. Therefore, trimellitic acid is preferable.

  Examples of the alcohol component include aromatic diols, preferably alkylene (2 to 3 carbon atoms) oxide adducts (average number of added moles 1 to 16) of bisphenol A, and ethylene oxide adducts and propylene oxide adducts of bisphenol A. More preferably, at least one selected from the group consisting of ethylene oxide adduct and propylene oxide adduct of bisphenol A is more preferable, and it is more preferable to use a mixture of these.

From the viewpoint of improving the efficiency of the polycondensation reaction, the catalyst used for the production of the amorphous polyester (a) is preferably at least one selected from a tin compound and a titanium compound, more preferably a tin compound, and di (2- More preferred is at least one selected from (ethylhexanoic acid) tin and dibutyltin oxide.
Examples of the titanium compound include titanium diisopropylate bistriethanolamate.
The amount of the catalyst used is preferably 0.01 to 1 part by weight, more preferably 0.1 to 0.6 part by weight, based on 100 parts by weight of the total amount of the acid component and the alcohol component in the amorphous polyester (a). preferable.

  The polycondensation reaction is preferably carried out by putting an acid component and an alcohol component in a reaction vessel and maintaining the reaction at 140 to 250 ° C. for 5 to 15 hours. Further, it is preferable that the pressure is reduced to 5.0 to 20 kPa and maintained for 1 to 10 hours.

The lower limit of the glass transition point of the amorphous polyester (a) is preferably 50 ° C., more preferably 55 ° C., from the viewpoint of improving the durability, low-temperature fixability and heat-resistant storage stability of the toner. Preferably it is 58 degreeC, and an upper limit becomes like this. Preferably it is 70 degreeC, More preferably, it is 68 degreeC, More preferably, it is 66 degreeC. From these viewpoints, the glass transition point is preferably 50 to 70 ° C, more preferably 55 to 68 ° C, and still more preferably 58 to 66 ° C.
The softening point of the amorphous polyester (a) is preferably 70 to 165 ° C, more preferably 70 to 140 ° C, and still more preferably 90 to 140 ° C, from the viewpoint of improving the low temperature fixability and heat resistant storage stability of the toner. 100-130 degreeC is still more preferable.

The lower limit of the number average molecular weight of the amorphous polyester (a) is preferably 1,000, more preferably 1,500, from the viewpoint of improving the durability, low-temperature fixability and heat-resistant storage stability of the toner. The upper limit is preferably 50,000, more preferably 10,000, and still more preferably 4,000. From these viewpoints, the number average molecular weight is preferably 1,000 to 50,000, more preferably 1,500 to 10,000, and still more preferably 2,000 to 4,000.
From the viewpoint of easily emulsifying the resin in an aqueous medium, the lower limit of the acid value of the amorphous polyester (a) is preferably 6 mgKOH / g, more preferably 10 mgKOH / g, still more preferably 15 mgKOH / g. g, and the upper limit is preferably 35 mgKOH / g. From these viewpoints, the acid value is preferably 6 to 35, more preferably 10 to 35 mgKOH / g, and still more preferably 15 to 35 mgKOH / g.
In the case where two or more kinds of amorphous polyesters are used as the amorphous polyester (a), the glass transition point and the softening point thereof are a mixture of two or more kinds of amorphous polyesters. Is the value obtained by The number average molecular weight and acid value of the amorphous polyester (a) are determined by the method described in the examples using a mixture in which all the amorphous polyesters are mixed at a ratio of using the amorphous polyester. The same applies to amorphous polyester (c) described later.

<Amorphous polyesters (a-1) and (a-2)>
The amorphous polyester (a) may be used alone or in combination of two or more, but preferably used in combination of two or more, the amorphous polyester (a-1) shown below or (A-2) is preferably used, and amorphous polyesters (a-1) and (a-2) are more preferably used in combination. Further, from the viewpoint of improving the heat resistant storage stability, the amorphous polyester (a-2) is preferably an amorphous polyester (a-2) having a higher softening point than (a-1).
The difference in softening point between the amorphous polyester (a-1) and the amorphous polyester (a-2) is preferably 5 ° C or higher, more preferably 7 ° C or higher, and preferably 30 ° C or lower. More preferably, it is 20 ° C. or lower. From these viewpoints, the difference in softening point is preferably 5 to 30 ° C, and more preferably 7 to 20 ° C.

(Amorphous polyester (a-1))
As an acid component of the amorphous polyester (a-1), an aliphatic compound is used from the viewpoint of enhancing the dispersibility of the pigment and the compatibility with the crystalline polyester, and thus improving the image density and the low-temperature fixability of the toner. It preferably contains a dicarboxylic acid.
As the aliphatic dicarboxylic acid, those described above are preferably used, and fumaric acid is preferable from the viewpoint of improving the low-temperature fixability and heat-resistant storage stability of the toner.
The acid component preferably further contains an aromatic dicarboxylic acid, and preferably terephthalic acid.

The lower limit of the proportion of the aliphatic dicarboxylic acid in the carboxylic acid of the amorphous polyester (a-1) is preferably 20 mol%, more preferably 40 mol%, from the viewpoints of low-temperature fixability and heat-resistant storage stability. More preferably, it is 50 mol%, and the upper limit is preferably 80 mol%, more preferably 70 mol%. From these viewpoints, the proportion is preferably 20 to 80 mol%, more preferably 40 to 70 mol%, and still more preferably 50 to 70 mol%.
The ratio of the aromatic carboxylic acid in the carboxylic acid of the amorphous polyester (a-1) is preferably 20 mol%, more preferably 30 mol%, from the viewpoints of low-temperature fixability and heat-resistant storage stability. The upper limit is preferably 80 mol%, more preferably 60 mol%, and even more preferably 50 mol%. From these viewpoints, the proportion is preferably 20 to 80 mol%, more preferably 30 to 60 mol%, and still more preferably 30 to 50 mol%.

  Preferred alcohol components include aromatic diols, more preferably at least one selected from ethylene oxide adducts and propylene oxide adducts of bisphenol A, and more preferably a mixture of these two.

  The ratio of the aromatic diol in the alcohol component of the amorphous polyester (a-1) is preferably 60 to 100 mol%, more preferably 80 to 100, from the viewpoint of improving low-temperature fixability and heat-resistant storage stability. It is mol%, More preferably, it is 90-100 mol%, More preferably, it is substantially 100 mol%, More preferably, it is 100 mol%.

  As for amorphous polyester (a-1), it is preferable that an alcohol component consists of an ethylene oxide addition product and propylene oxide addition product of bisphenol A, and an acid component consists of terephthalic acid and fumaric acid.

(Amorphous polyester (a-2))
Examples of the acid component of the amorphous polyester (a-2) include dicarboxylic acids and trivalent or higher polyvalent carboxylic acids. Among these, dicarboxylic acids are preferable, and dicarboxylic acids and trivalent or higher polyvalent carboxylic acids are used. It is more preferable to use together.
As the dicarboxylic acid, those described above are preferably used, and at least one selected from alkyl succinic acid having an alkyl group having 9 to 14 carbon atoms, alkenyl succinic acid having an alkenyl group having 9 to 14 carbon atoms, and aromatic dicarboxylic acid. Species are preferred, and dodecenyl succinic acid is particularly preferred from the viewpoint of enhancing the low-temperature fixability of the toner.
The alkyl group and alkenyl group of the alkyl succinic acid having an alkyl group having 9 to 14 carbon atoms and the alkenyl succinic acid having an alkenyl group having 9 to 14 carbon atoms are preferably a branched alkyl group and a branched alkenyl group.
The branched structure may exist in any part of the alkyl group and the alkenyl group, but a mixture having a plurality of branched structures is preferable from the viewpoint of enhancing the compatibility with the crystalline polyester.
In the carboxylic acid of the amorphous polyester (a-2), an alkyl succinic acid having an alkyl group having 9 to 14 carbon atoms and an alkenyl succinic acid having an alkenyl group having 9 to 14 carbon atoms have an affinity for a crystalline polyester. From the standpoint of enhancing the toner properties and thus the low-temperature fixability of the toner, the lower limit is preferably 1 mol%, more preferably 2 mol%, still more preferably 3 mol%, and the upper limit is preferably 40 mol%. Preferably it is 30 mol%, More preferably, it is 20 mol%, More preferably, it is 10 mol%. From this viewpoint, the alkenyl succinic acid is preferably contained in the acid component in an amount of 1 to 40 mol%, more preferably 2 to 30 mol%, still more preferably 3 to 20 mol%, and still more preferably. 3 to 10 mol% is contained.
As the aromatic dicarboxylic acid, terephthalic acid is preferred.
The ratio of the aromatic dicarboxylic acid in the carboxylic acid of the amorphous polyester (a-2) is preferably 40 mol%, more preferably 50 mol%, from the viewpoints of low-temperature fixability and heat-resistant storage stability. More preferably, it is 60 mol%, and the upper limit is preferably 90 mol%, more preferably 80 mol%, still more preferably 70 mol%. From these viewpoints, the proportion is preferably 40 to 90 mol%, more preferably 50 to 80 mol%, still more preferably 60 to 70 mol%.

Examples of the trivalent to pentavalent aromatic carboxylic acid include those described above, and trimellitic acid is particularly preferable from the viewpoint of improving the heat resistant storage stability of the toner.
From the viewpoint of improving the heat resistant storage stability of the toner, the trivalent to pentavalent aromatic carboxylic acid is preferably contained in the acid component in an amount of 5 to 40 mol%, more preferably 10 to 30 mol%, and still more preferably. 20-30 mol% is contained.

  Preferred alcohol components include aromatic diols, alkylene (2 to 3 carbon atoms) oxide adducts (average number of added moles 1 to 16) of bisphenol A are preferred, ethylene oxide adducts and propylene oxide adducts of bisphenol A Are more preferable, and it is more preferable to use a mixture of these.

  The ratio of the aromatic diol in the alcohol component of the amorphous polyester (a-2) is preferably 60 to 100 mol%, more preferably 80 to 100, from the viewpoint of improving low-temperature fixability and heat-resistant storage stability. It is mol%, More preferably, it is 90-100 mol%, More preferably, it is substantially 100 mol%, More preferably, it is 100 mol%.

  The amorphous polyester (a-2) is preferably composed of an ethylene oxide adduct of bisphenol A and a propylene oxide adduct of the bisphenol A, and an acid component of terephthalic acid, alkenyl succinic acid and trimellitic acid. Is more preferably composed of an ethylene oxide adduct and a propylene oxide adduct of bisphenol A, and the acid component is preferably composed of terephthalic acid, dodecenyl succinic acid and trimellitic acid.

[Crystalline Polyester (b)]
The resin particles (A) preferably contain the crystalline polyester (b) from the viewpoint of heat resistant storage stability.
In the present invention, the crystalline polyester has a crystallinity index of 0.6 to 1.4, preferably 0.8 to 1.3 from the viewpoint of low-temperature fixability of the toner. The thing of 9-1.2 is more preferable, and the thing of 0.9-1.1 is still more preferable.
The crystalline polyester (b) preferably has an acid group at the molecular terminal from the viewpoint of facilitating the dispersion of the resin particle dispersion during toner production and enhancing the dispersion stability. Examples of the acid group include a carboxy group, a sulfonic acid group, a phosphonic acid group, and a sulfinic acid. Among these, a carboxy group is preferable from the viewpoint of achieving both the dispersibility of the resin and the heat-resistant storage stability of the obtained toner.
The total amount of the crystalline polyester (b) and the amorphous polyester (a) in the core portion is the resin constituting the resin particles (A) in the resin constituting the core portion from the viewpoint of improving the low-temperature fixability of the toner. Among them, preferably 50 to 100% by mass, more preferably 80 to 100% by mass, still more preferably 90 to 100% by mass, further preferably substantially 100% by mass, and further preferably 100% by mass. . The mass ratio ((b) / (a)) of the crystalline polyester (b) and the amorphous polyester (a) improves the low-temperature fixability and heat-resistant storage stability of the toner, and improves the image density. It is preferably 5/95 to 50/50, more preferably 5/95 to 40/60, further preferably 10/90 to 40/60, further preferably 10/90 to 30/70, 15 / 85 to 20/80 is more preferable.

The melting point of the crystalline polyester (b) is preferably 50 to 150 ° C, more preferably 60 to 100 ° C, and more preferably 70 to 90 ° C from the viewpoint of improving the low-temperature fixability and heat-resistant storage stability of the toner and improving the image density. Is more preferable.
From the same viewpoint, the softening point of the crystalline polyester (b) is preferably from 50 to 140 ° C, more preferably from 55 to 110 ° C, still more preferably from 70 to 90 ° C.
The number average molecular weight of the crystalline polyester (b) is preferably 1,500 to 50,000, more preferably 2,000 to 10,000, from the viewpoint of improving the low-temperature fixability and heat-resistant storage stability of the toner. 000 to 5,000 are more preferable.
The acid value of the crystalline polyester (b) is preferably 5 to 30 mgKOH / g, and preferably 10 to 25 mgKOH / g from the viewpoint of improving the dispersion stability of the resin particle dispersion of the toner and the low temperature fixability and heat resistant storage stability of the toner. Is more preferable, and 15-22 mgKOH / g is still more preferable.
In addition, crystalline polyester (b) can be used individually or in combination of 2 or more types.
In the present invention, the melting point, softening point and number average molecular weight of the crystalline polyester (b) are determined by the methods described in the examples.
When two or more kinds of crystalline polyesters are used as the crystalline polyester (b), the melting point of the crystalline polyester having the largest mass ratio among the crystalline polyesters contained in the obtained toner is the crystalline property in the present invention. It is set as melting | fusing point of polyester (b). When all have the same ratio, the lowest value is set. The softening point, the number average molecular weight, and the acid value of the crystalline polyester (b) are determined by the method described in the examples using a mixture in which all the crystalline polyesters are mixed at a ratio.

The crystalline polyester (b) can be produced by subjecting an acid component and an alcohol component to a polycondensation reaction. In the polycondensation reaction, a catalyst is preferably used, and preferable catalyst and polycondensation reaction conditions are the same as those for the amorphous polyester (a).
Examples of the acid component include aliphatic dicarboxylic acid, alicyclic dicarboxylic acid, aromatic dicarboxylic acid, and trivalent or higher polyvalent carboxylic acid, and among them, improve low-temperature fixability, heat-resistant storage stability and chargeability of the toner. From the viewpoint, an aliphatic dicarboxylic acid is preferable.
The aliphatic dicarboxylic acid preferably has 2 to 18 carbon atoms and more preferably 8 to 12 carbon atoms from the viewpoint of improving the heat-resistant storage stability of the toner and improving the image density.
Examples of the aliphatic dicarboxylic acid having 2 to 18 carbon atoms include oxalic acid, malonic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, succinic acid, adipic acid, sebacic acid, 1,12-dodecanedioic acid. , Azelaic acid, n-dodecyl succinic acid, n-dodecenyl succinic acid and the like. Among them, sebacic acid is preferable from the viewpoint of improving the low-temperature fixability and heat-resistant storage stability of the toner.
Examples of the alicyclic dicarboxylic acid include cyclohexane dicarboxylic acid.
Examples of aromatic dicarboxylic acids include phthalic acid, isophthalic acid, terephthalic acid and the like, with terephthalic acid being preferred.
Examples of the trivalent or higher polyvalent carboxylic acid include trimellitic acid and pyromellitic acid.
These can be used alone or in combination of two or more.

Examples of alcohol components include aliphatic diols, aromatic diols, hydrogenated bisphenol A, and trihydric or higher polyhydric alcohols, among others, promoting the crystallization of polyester and improving the low-temperature fixability of the toner. From the viewpoint of making them, an aliphatic diol is preferable.
Among the aliphatic diols, α, ω-alkanediol is preferable from the viewpoint of promoting the crystallization of polyester and improving the low-temperature fixability of the toner.
The α, ω-alkanediol preferably has 2 to 18 carbon atoms, more preferably 4 to 12 carbon atoms, and more preferably 4 to 12 carbon atoms from the viewpoint of improving the low-temperature fixability and heat-resistant storage stability of the obtained toner and improving the image density. 6-12 are still more preferable.
Examples of the α, ω-alkanediol having 2 to 18 carbon atoms include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1, Examples include 6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,12-dodecanediol, and the like. From the viewpoint of improving low-temperature fixability and heat-resistant storage stability, 1,6-hexanediol and 1,9-nonanediol are preferable, and from the viewpoint of improving heat-resistant storage stability, 1,9-nonanediol is preferable.
The α, ω-alkanediol having 2 to 18 carbon atoms can be used alone or in combination of two or more.
Examples of aromatic diols include alkylene (2 to 3 carbon) oxide adducts (average number of added moles 1 to 16) of bisphenol A.
Examples of the trihydric or higher polyhydric alcohol include glycerin and pentaerythritol.

The alcohol component can be used alone or in combination of two or more. From the viewpoint of promoting the crystallization of the polyester, the alcohol component contains 80 to 100 α, ω-alkanediol having 2 to 18 carbon atoms. It is preferable that it is mol%, and it is more preferable that it is 90-100 mol%.
In the crystalline polyester (b), the acid component is preferably an aliphatic dicarboxylic acid and the alcohol component is an aliphatic diol, more preferably the acid component is sebacic acid and the alcohol component is an aliphatic diol, and still more preferably the acid component. Is sebacic acid and the alcohol component is 1,9-nonanediol.

[Carbon black]
The carbon black is preferably at least one selected from channel black and furnace black from the production method, more preferably furnace black, and in particular, at least one selected from high-color and medium-color furnaces that are carbon black for color. Species are preferred.
About pH value of carbon black, pH 1-11 are preferable from a viewpoint of storage stability, pH 6-11 are more preferable, and pH 7-10 are still more preferable.
The specific surface area is preferably from 70 to 1600 m ² / g, more preferably from 70 to 600 m ² / g, and even more preferably from 100 to 400 m ² / g, from the viewpoint of improvement in toner fluidity, heat-resistant storage stability and image density.
The particle size is preferably from 10 to 40 nm, more preferably from 10 to 20 nm, from the viewpoint of improving the fluidity of the toner, heat resistant storage stability and image density.
DBP For (dibutyl phthalate) oil absorption amount, the flowability of the toner, from the viewpoint of heat storage stability and improvement in image density of, 40~1000cm ³ / 100g are preferred, more preferably 50 to 200 cm ^3/100 g, particularly preferably 50 ~150cm is a ³ / 100g.
The coloring power index is preferably from 50 to 200, more preferably from 100 to 180, from the viewpoint of improving the fluidity of the toner, heat-resistant storage stability and image density.
The volatile content is preferably from 0 to 20% by mass, more preferably from 0 to 5% by mass, and even more preferably from 1 to 2% by mass, from the viewpoint of improvement in toner fluidity, heat-resistant storage stability and image density.
The pH of carbon black is measured by the method of JIS Z8820 by preparing a water-soluble suspension or mud of 20% by mass of carbon black. The specific surface area (BET method) and DBP oil absorption of carbon black are measured by the method of JIS K6217. The average particle diameter is an average primary particle diameter which is an average diameter (100 number average particle diameter) measured and calculated by an electron microscope. The coloring power index is measured by the method of ASTM D3265, and the volatile content is a value obtained by heating at 950 ° C. for 7 minutes.
Specific examples of commercially available carbon black include MONARCH 1100, 880, 800 series manufactured by Cabot, REGAL 330R, 300R series, Printex 95, 90, 85, 80, 60, 55, 45, 40, manufactured by Degussa. Examples include L6, P series, MCF88, MA600 manufactured by Mitsubishi Chemical Corporation.

[Copper phthalocyanine having an anionic group]
The anionic group of copper phthalocyanine having an anionic _{group, -COOM, -SO 3 M, -SO} 2 M, -RSO 2 M, -PO 3 HM, -PO 3 M ( where, M in the formula Represents a hydrogen atom, an alkali metal, an alkaline earth metal, aluminum, ammonium or organic ammonium, and R has an alkylene group having 1 to 12 carbon atoms, a phenylene group which may have a substituent, or a substituent. A naphthylene group which may be present)), or one or more functional groups selected from the group consisting of salts thereof. Among these acidic groups, a sulfonic acid group (—SO ₃ M) is preferable from the viewpoint of dispersion stability.
As said alkali metal, at least 1 sort (s) chosen from sodium, potassium, and lithium is mentioned suitably, Calcium is mentioned suitably as an alkaline-earth metal, Aluminum is mentioned suitably as another metal.
The organic ammonium is preferably at least one selected from octadecyl ammonium, didodecyl ammonium, dimethyl octadecyl ammonium, dimethyl dioctadecyl ammonium and benzyl dimethyl octadecyl ammonium, and more preferably dimethyl dioctadecyl ammonium.
Copper phthalocyanine sulfonate can be synthesized by reacting copper phthalocyanine with a sulfonating agent such as concentrated sulfuric acid, fuming sulfuric acid, and chlorosulfuric acid by a known method.
The copper phthalocyanine having an anionic group is preferably at least one selected from copper phthalocyanine sulfonic acid alkylamine and copper phthalocyanine sulfonic acid, and more preferably copper phthalocyanine sulfonic acid alkylamine.

[Release agent]
In the step (1), it is preferable to obtain aggregated particles (1) by aggregating the release agent particles containing the release agent together with the resin particles (A). Thereby, the effect of imparting releasability and improving the fixing property is obtained.
Release agents include low-molecular-weight polyolefins such as polyethylene, polypropylene, and polybutene; silicone waxes; fatty acid amides such as oleic acid amide and stearic acid amide; plant waxes; animal waxes such as beeswax; mineral and petroleum waxes; esters Synthetic waxes such as waxes may be mentioned.
Examples of plant waxes include carnauba wax, rice wax, and candelilla wax, and carnauba wax is preferred.
Examples of the mineral / petroleum wax include montan wax, paraffin wax, and Fischer-Tropsch wax, and paraffin wax is preferred.
These release agents are preferably used alone or in combination of two or more. In particular, it is preferable to use a plant wax and a mineral / petroleum wax in combination from the viewpoint of improving the low-temperature fixability of the toner, and it is more preferable to use a carnauba wax and a paraffin wax in combination.
The melting point of the release agent is preferably 60 to 100 ° C., more preferably 60 to 90 ° C., further preferably 70 to 90 ° C., and still more preferably 80 to 90 ° C., from the viewpoint of improving the heat resistant storage stability of the toner. . When using 2 or more types together, it is preferable that melting | fusing point of all is 60-90 degreeC from a viewpoint of improving the low temperature fixability of a toner.
In the present invention, the melting point of the release agent is determined by the method described in the examples. When two or more kinds are used in combination, the melting point of the release agent having the largest mass ratio among the release agents contained in the obtained toner is the melting point of the release agent in the present invention. When all have the same ratio, the lowest value is set.
The amount of the release agent used is preferably 1 to 20 parts by mass, and 2 to 15 parts by mass with respect to 100 parts by mass of the resin in the toner from the viewpoint of improving the releasability of the toner and improving the low-temperature fixability. Is more preferable.

[Amorphous polyester (c)]
The black toner of the present invention contains the amorphous polyester (c) in the shell portion from the viewpoint of improving the heat resistant storage stability.
The acid component and carboxylic acid component of the amorphous polyester (c) are preferably the same as those of the amorphous polyester (a).
The total amount of the amorphous polyester (c) in the shell portion is preferably 50 to 100% by mass, more preferably 80 to 100% in the resin constituting the resin particles (C) from the viewpoint of improving the heat resistant storage stability of the toner. It is 90 mass%, More preferably, it is 90-100 mass%, More preferably, it is 100 mass% substantially, More preferably, it is 100 mass%.

The lower limit of the glass transition point of the amorphous polyester (c) is preferably 50 ° C., more preferably 55 ° C., from the viewpoint of improving the durability, low-temperature fixability and heat-resistant storage stability of the toner. Preferably it is 58 degreeC, and an upper limit becomes like this. Preferably it is 70 degreeC, More preferably, it is 68 degreeC, More preferably, it is 66 degreeC. From these viewpoints, the glass transition point is preferably 50 to 70 ° C, more preferably 55 to 68 ° C, and still more preferably 58 to 66 ° C.
The softening point of the amorphous polyester (c) is preferably 70 to 165 ° C, more preferably 70 to 140 ° C, and still more preferably 90 to 140 ° C, from the viewpoint of improving the low-temperature fixability and heat-resistant storage stability of the toner. 100-130 degreeC is still more preferable.

The lower limit of the number average molecular weight of the amorphous polyester (c) is preferably 1,000, more preferably 1,500 from the viewpoint of improving the durability, low-temperature fixability and heat-resistant storage stability of the toner. The upper limit is preferably 50,000, more preferably 10,000, and still more preferably 4,000. From these viewpoints, the number average molecular weight is preferably 1,000 to 50,000, more preferably 1,500 to 10,000, and still more preferably 2,000 to 4,000.
From the viewpoint of easily dispersing the resin in an aqueous medium, the lower limit of the acid value of the amorphous polyester (c) is preferably 6 mgKOH / g, more preferably 10 mgKOH / g, and still more preferably 15 mgKOH / g. g, and the upper limit is preferably 35 mgKOH / g. From these viewpoints, the acid value is preferably 6 to 35 mgKOH / g, more preferably 10 to 35 mgKOH / g, and still more preferably 15 to 35 mgKOH / g.

<Amorphous polyesters (c-1) and (c-2)>
The amorphous polyester (c) may be used singly or in combination of two or more. However, from the viewpoint of heat-resistant storage stability, it is preferable to use two or more in combination. It is preferable to use polyester (c-1) or (c-2), more preferably amorphous polyester (c-1), and amorphous polyesters (c-1) and (c-2). It is more preferable to use together. The amorphous polyester (c-2) is preferably an amorphous polyester (c-2) having a softening point higher than that of (c-1).
The difference in softening point between the amorphous polyester (c-1) and the amorphous polyester (c-2) is preferably 5 ° C or higher, more preferably 7 ° C or higher, and preferably 30 ° C or lower. More preferably, it is 20 ° C. or lower. From these viewpoints, the difference in softening point is preferably 5 to 30 ° C, and more preferably 7 to 20 ° C.
The amorphous polyester (c) can be produced by polycondensation reaction between an acid component and an alcohol component. In the polycondensation reaction, a catalyst is preferably used, and preferable catalyst and polycondensation reaction conditions are the same as those for the amorphous polyester (a).

(Amorphous polyester (c-1))
The acid component of the amorphous polyester (c-1) preferably contains an aliphatic dicarboxylic acid from the viewpoint of enhancing compatibility with the core portion and thus improving the fluidity of the toner.
The aliphatic dicarboxylic acid preferably has 2 to 12 carbon atoms and more preferably 2 to 6 carbon atoms from the viewpoint of improving the fluidity of the toner.
Examples of the aliphatic dicarboxylic acid having 2 to 12 carbon atoms include those similar to the amorphous polyester (a-1), and fumaric acid is preferable.
The acid component preferably further contains an aromatic dicarboxylic acid, and the aromatic dicarboxylic acid is preferably terephthalic acid.

The ratio of the aliphatic dicarboxylic acid in the carboxylic acid of the amorphous polyester (c-1) is preferably 20 mol%, more preferably 40 mol%, from the viewpoints of low-temperature fixability and heat-resistant storage stability. More preferably, it is 50 mol%, and the upper limit is preferably 80 mol%, more preferably 70 mol%. From these viewpoints, the proportion is preferably 20 to 80 mol%, more preferably 40 to 70 mol%, and still more preferably 50 to 70 mol%.
The ratio of the aromatic carboxylic acid in the carboxylic acid of the amorphous polyester (c-1) is preferably 20 mol%, more preferably 30 mol%, from the viewpoint of low-temperature fixability and heat-resistant storage stability. The upper limit is preferably 80 mol%, more preferably 60 mol%, and even more preferably 50 mol%. From these viewpoints, the proportion is preferably 20 to 80 mol%, more preferably 30 to 60 mol%, and still more preferably 30 to 50 mol%.

  Preferred alcohol components include aromatic diols, alkylene (2 to 3 carbon) oxide adducts of bisphenol A (average addition mole number of 1 to 16) are preferred, ethylene oxide adducts and propylene oxide additions of bisphenol A More preferred is at least one selected from those.

The ratio of the aromatic diol in the alcohol component of the amorphous polyester (c-1) is preferably 60 to 100 mol%, more preferably 80 to 100, from the viewpoint of improving low-temperature fixability and heat-resistant storage stability. It is mol%, More preferably, it is 90-100 mol%, More preferably, it is substantially 100 mol%, More preferably, it is 100 mol%.
In the amorphous polyester (c-1), it is preferable that the alcohol component is composed of an ethylene oxide adduct of bisphenol A and a propylene oxide adduct, and the acid component is composed of terephthalic acid and fumaric acid.

(Amorphous polyester (c-2))
Examples of the acid component of the amorphous polyester (c-2) include dicarboxylic acids and trivalent or higher polyvalent carboxylic acids. Among them, dicarboxylic acids are preferable, and dicarboxylic acids and trivalent or higher polyvalent carboxylic acids are used. It is more preferable to use together.
The dicarboxylic acid is preferably at least one selected from alkyl succinic acid having an alkyl group having 9 to 14 carbon atoms, alkenyl succinic acid having an alkenyl group having 9 to 14 carbon atoms, and aromatic dicarboxylic acid. More preferably, an aromatic dicarboxylic acid is used in combination with at least one selected from alkyl succinic acid having 14 alkyl groups and alkenyl succinic acid having 9 to 14 carbon atoms, specifically, amorphous. The same thing as quality polyester (a-1) is mentioned, A dodecenyl succinic acid is preferable. The alkyl group and alkenyl group of the alkyl succinic acid having an alkyl group having 9 to 14 carbon atoms and the alkenyl succinic acid having an alkenyl group having 9 to 14 carbon atoms are preferably a branched alkyl group and a branched alkenyl group.
In the carboxylic acid of the amorphous polyester (c-2), an alkyl succinic acid having an alkyl group having 9 to 14 carbon atoms and an alkenyl succinic acid having an alkenyl group having 9 to 14 carbon atoms have an affinity for a crystalline polyester. From the standpoint of enhancing the toner properties and thus the low-temperature fixability of the toner, the lower limit is preferably 1 mol%, more preferably 2 mol%, still more preferably 3 mol%, and the upper limit is preferably 40 mol%. Preferably it is 30 mol%, More preferably, it is 20 mol%, More preferably, it is 10 mol%. From this viewpoint, the alkenyl succinic acid is preferably contained in the acid component in an amount of 1 to 40 mol%, more preferably 2 to 30 mol%, still more preferably 3 to 20 mol%, and still more preferably. 3 to 10 mol% is contained.
As the aromatic dicarboxylic acid, terephthalic acid is preferred.
The ratio of the aromatic carboxylic acid in the carboxylic acid of the amorphous polyester (c-2) is preferably 40 mol%, more preferably 50 mol%, from the viewpoint of low-temperature fixability and heat-resistant storage stability. More preferably, it is 60 mol%, and the upper limit is preferably 90 mol%, more preferably 80 mol%, still more preferably 70 mol%. From these viewpoints, the proportion is preferably 40 to 90 mol%, more preferably 50 to 80 mol%, still more preferably 60 to 70 mol%.

Examples of the trivalent to pentavalent aromatic carboxylic acid include at least one selected from trimellitic acid, 2,5,7-naphthalenetricarboxylic acid, and pyromellitic acid. Among them, the viewpoint of improving the heat resistant storage stability of the toner. Therefore, trimellitic acid is preferable.
From the viewpoint of improving the heat resistant storage stability of the toner, the trivalent to pentavalent aromatic carboxylic acid is preferably contained in the acid component in an amount of 5 to 30 mol%, more preferably 7 to 20 mol%, and still more preferably. 9 to 11 mol% is contained.

  Preferred alcohol components include aromatic diols, alkylene (2 to 3 carbon atoms) oxide adducts (average number of added moles 1 to 16) of bisphenol A are preferred, ethylene oxide adducts and propylene oxide adducts of bisphenol A Are more preferable, and it is more preferable to use a mixture of these.

  The ratio of the aromatic diol in the alcohol component of the amorphous polyester (c-2) is preferably 60 to 100 mol%, more preferably 80 to 100, from the viewpoint of improving the low-temperature fixability and the heat-resistant storage stability. It is mol%, More preferably, it is 90-100 mol%, More preferably, it is substantially 100 mol%, More preferably, it is 100 mol%.

  The amorphous polyester (c-2) is preferably composed of an ethylene oxide adduct of bisphenol A and a propylene oxide adduct of the bisphenol A, and an acid component of terephthalic acid, alkenyl succinic acid and trimellitic acid. Is more preferably composed of an ethylene oxide adduct and a propylene oxide adduct of bisphenol A, and the acid component is preferably composed of terephthalic acid, dodecenyl succinic acid and trimellitic acid.

[Resin particles (A)]
The resin particles (A) contain amorphous polyester (a), carbon black, and copper phthalocyanine having an anionic group. From the viewpoint of improving toner fixability and image density, the resin particles (A) preferably further contain a crystalline polyester (b).
The total content of the amorphous polyester (a), carbon black, copper phthalocyanine having an anionic group and the crystalline polyester (b) in the resin particles (A) depends on the fluidity of the toner particles, the heat-resistant storage stability and the image. From the viewpoint of concentration, it is preferably 70 to 100% by mass, more preferably 80 to 100% by mass, and still more preferably 90 to 100% by mass.
The content of the amorphous polyester (a) in the resin constituting the resin particles (A) is preferably 60% by mass from the viewpoint of fluidity of the toner particles, heat resistant storage stability and image density, More preferably, it is 70% by mass, further preferably 80% by mass, the upper limit is preferably 100% by mass, more preferably substantially 100% by mass, more preferably 95% by mass, More preferably, it is 90 mass%.
The content of the crystalline polyester (b) in the resin constituting the resin particles (A) is preferably a lower limit of 5% by mass from the viewpoints of fluidity of the toner particles, heat resistant storage stability and image density. Preferably it is 10 mass%, More preferably, it is 12 mass%, and an upper limit becomes like this. Preferably it is 30 mass%, More preferably, it is 25 mass%, More preferably, it is 20 mass%.
The lower limit of the ratio of carbon black to 100 parts by mass of the resin constituting the resin particles (A) is preferably 1 part by mass from the viewpoint of fluidity of toner particles, heat resistant storage stability and image density, more preferably 3 parts. The upper limit is preferably 20 parts by mass, more preferably 15 parts by mass, and even more preferably 10 parts by mass. In this respect, the proportion of carbon black is preferably 1 to 20 parts by mass, more preferably 3 to 15 parts by mass, and still more preferably 5 to 10 parts by mass.
The lower limit of the ratio of the copper phthalocyanine having an anionic group to 100 parts by mass of the resin constituting the resin particles (A) is preferably 0.05 parts by mass from the viewpoints of the fluidity of the toner particles, heat resistant storage stability and image density. More preferably, it is 0.1 parts by mass, still more preferably 0.5 parts by mass, the upper limit is preferably 5 parts by mass, more preferably 3 parts by mass, still more preferably 2 parts by mass. Part, more preferably 1.5 parts by weight.
The copper phthalocyanine having an anionic group has a lower limit of preferably 0.1 parts by mass, more preferably 1 part by mass with respect to 100 parts by mass of carbon black from the viewpoint of improving fluidity, heat-resistant storage stability and image density. The upper limit value is preferably 30 parts by weight, more preferably 25 parts by weight, still more preferably 20 parts by weight, and even more preferably 18 parts by weight. . From this viewpoint, the copper phthalocyanine having an anionic group is preferably 0.1 to 30 parts by mass, more preferably 1 to 25 parts by mass, still more preferably 1 to 20 parts by mass, and still more preferably. Is 5 to 20 parts by mass, more preferably 10 to 18 parts by mass.
The resin particles (A) are obtained by dispersing a component containing amorphous polyester (a), carbon black, and copper phthalocyanine having an anionic group in an aqueous medium to obtain a dispersion containing resin particles (A). In particular, an aqueous medium is gradually added to a resin mixture containing amorphous polyester (a), carbon black, and copper phthalocyanine having an anionic group to effect phase inversion emulsification, and resin particles ( It is preferred to obtain A). Hereinafter, the phase inversion emulsification method will be described.

<Phase inversion emulsification method>
(Production of resin mixture)
In the phase inversion emulsification method, first, an amorphous polyester (a), carbon black, and a component containing copper phthalocyanine having an anionic group are melted and mixed in the presence of an alkaline aqueous solution to obtain a resin mixture. .
When the said component contains other resin, for example, crystalline polyester (b), what mixed the said component and other resin beforehand may be used, but when adding the said aqueous alkali solution and an arbitrary component It may be obtained by simultaneously adding to, melting and mixing. For example, amorphous polyester (a), crystalline polyester (b), carbon black, and copper phthalocyanine having an anionic group are melted and mixed in the presence of an alkaline aqueous solution to obtain a resin mixture. This is preferable from the viewpoint of improving the low-temperature fixability. From this point of view, first, the amorphous polyester (a) and other resin such as the crystalline polyester (b) are mixed, and then the mixture, carbon black, and copper phthalocyanine having an anionic group are added. It is also preferable to melt and mix in the presence of an aqueous alkali solution to obtain a resin mixture. In the present specification, a mixture obtained by mixing the amorphous polyester (a) and another resin such as the crystalline polyester (b) is referred to as “resin containing the amorphous polyester (a)”. Sometimes.
In mixing, it is preferable to add a surfactant from the viewpoint of improving the emulsion stability of the resin.

  The alkali in the alkaline aqueous solution is preferably an alkali metal hydroxide such as potassium hydroxide or sodium hydroxide, or ammonia, and more preferably potassium hydroxide or sodium hydroxide from the viewpoint of improving the dispersibility of the resin. Moreover, 1-30 mass% is preferable, as for the density | concentration of the alkali in alkaline aqueous solution, 1-25 mass% is more preferable, and 1.5-20 mass% is still more preferable.

Examples of the surfactant include nonionic surfactants, anionic surfactants, cationic surfactants, etc. Among them, nonionic surfactants are preferable, and nonionic surfactants and anionic surfactants or It is more preferable to use a cationic surfactant in combination, and it is more preferable to use a nonionic surfactant and an anionic surfactant in combination from the viewpoint of improving the emulsion stability of the resin.
When a nonionic surfactant and an anionic surfactant are used in combination, the mass ratio of the nonionic surfactant to the anionic surfactant (nonionic surfactant / anionic surfactant) is the emulsification of the resin. From the viewpoint of improving stability, 0.3 to 10 is preferable, and 0.5 to 5 is more preferable.

Examples of nonionic surfactants include polyoxyalkylene alkyl ethers, polyoxyalkylene alkyl aryl ethers, polyoxyalkylene fatty acid esters, oxyethylene / oxypropylene block copolymers, among others, improving the emulsion stability of resins. From the viewpoint of making it, polyoxyethylene alkyl ether is preferable.
Examples of the polyoxyalkylene alkyl ether include polyoxyethylene oleyl ether and polyoxyethylene lauryl ether.
Examples of the polyoxyalkylene alkyl aryl ether include polyoxyethylene nonyl phenyl ether.
Examples of the polyoxyalkylene fatty acid ester include polyethylene glycol monolaurate, polyethylene glycol monostearate, polyethylene glycol monooleate and the like.

Examples of anionic surfactants include alkylbenzene sulfonates, alkyl sulfates, alkyl ether sulfates, etc., and alkylbenzene sulfonates and alkyl ether sulfates are preferred from the viewpoint of improving the emulsion stability of the resin. .
As the alkyl benzene sulfonate, an alkali metal salt of alkyl benzene sulfonic acid is preferable, an alkali metal salt of dodecyl benzene sulfonic acid is preferable, and sodium dodecyl benzene sulfonate is more preferable. As the alkyl sulfate, an alkali metal salt of dodecyl sulfate is preferable. As the alkyl ether sulfate, an alkali metal salt of alkyl ether sulfate is preferable.

  The content of the surfactant is preferably 20 parts by mass or less, more preferably 15 parts by mass or less, still more preferably 0.1 to 10 parts by mass with respect to 100 parts by mass of the resin constituting the resin particles (A). 0.5-10 mass parts is still more preferable.

As a method for obtaining a resin mixture, a resin containing amorphous polyester (a), carbon black, copper phthalocyanine having an anionic group, an aqueous alkaline solution, and the above optional components, preferably a surfactant, are placed in a container and stirred. A method in which the resin is melted and mixed uniformly while stirring with a vessel is preferred.
The temperature at which the resin is melted and mixed is preferably equal to or higher than the glass transition point of the amorphous polyester (a) from the viewpoint of obtaining homogeneous resin particles, and the resin containing the amorphous polyester (a) is a crystalline polyester. When (b) is included, the melting point of the crystalline polyester (b) or higher is preferable.

(Phase inversion)
Next, an aqueous medium is added to the resin mixture and phase inversion is performed to obtain a dispersion containing resin particles (A).
The aqueous medium is preferably composed mainly of water, and from the viewpoint of improving the emulsion stability of the resin, the water content in the aqueous medium is preferably 80% by mass or more, more preferably 90% by mass or more, and 95 More preferably, it is more preferably at least 100% by mass, still more preferably 100% by mass, and even more preferably 100% by mass. The water is preferably deionized water or distilled water.
Components other than water include aliphatic alcohols having 1 to 5 carbon atoms such as ethanol and isopropanol; dialkyl (carbon numbers 1 to 3) ketones such as acetone and methyl ethyl ketone; organic solvents that dissolve in water such as cyclic ethers such as tetrahydrofuran Is used.

The temperature at which the aqueous medium is added is preferably equal to or higher than the glass transition point of the amorphous polyester (a). From the viewpoint of obtaining excellent resin particles, the melting point of the crystalline polyester (b) or higher is more preferable.
From the viewpoint of obtaining resin particles having a small particle size, the addition rate of the aqueous medium is 0.1 to 50 parts by mass / 100 parts by mass of the resin constituting the resin particles (A) until the phase inversion is completed. Preferably, it is 0.1 to 30 parts by weight / minute, more preferably 0.5 to 10 parts by weight / minute, and 0.5 to 5 parts by weight / minute. Is more preferable. There is no restriction | limiting in the addition rate of the aqueous medium after phase inversion.
The use amount of the aqueous medium is preferably 100 to 2000 parts by mass, and 150 to 1500 parts by mass with respect to 100 parts by mass of the resin constituting the resin particles (A) from the viewpoint of obtaining uniform aggregated particles in the subsequent aggregation step. More preferred is 150 to 500 parts by mass. From the viewpoint of improving the stability of the resulting resin particle dispersion, the solid content concentration is preferably 7 to 50% by mass, more preferably 10 to 40% by mass, still more preferably 20 to 40% by mass, and still more preferably. It is 25-35 mass%. In addition, solid content is the total amount of non-volatile components, such as resin and surfactant.

The volume median particle size of the resin particles (A) in the dispersion containing the obtained resin particles (A) is preferably 0.02 to 2 μm. From the viewpoint of obtaining a toner capable of obtaining a high-quality image, 0.02 to 1.5 μm is preferable, 0.05 to 1 μm is more preferable, and 0.05 to 0.5 μm is still more preferable. Here, the volume-median particle diameter is a particle diameter at which the cumulative volume frequency calculated by the volume fraction is 50% calculated from the smaller particle diameter, and is obtained by the method described in the examples.
Further, the coefficient of variation (CV value) (%) of the particle size distribution of the resin particles is preferably 40% or less, more preferably 35% or less, and more preferably 30% from the viewpoint of obtaining a toner capable of obtaining a high-quality image. The following is more preferable, and 28% or less is more preferable. The CV value is a value represented by the following formula, and is determined by the method described in the examples.
CV value (%) = (standard deviation of particle size distribution / volume average particle size (D _v )) × 100

From the viewpoint of improving the heat resistant storage stability and low-temperature fixability of the toner, it is preferable to crosslink the polyester resin contained in the resin particles (A), and it is more preferable to crosslink with a compound having an oxazoline group.
The compound having an oxazoline group preferably contains a plurality of oxazoline groups in the molecule, and more preferably a polymer containing an oxazoline group. The weight average molecular weight of the polymer containing an oxazoline group is preferably 500 to 2,000,000, more preferably 1,000 to 1,000,000, from the viewpoint of increasing the reactivity with the polyester resin.
Examples of commercially available polymers containing oxazoline groups include EPOCROSS WS series (water-soluble type, main chain acrylic), K series (emulsion type, main chain styrene / acrylic) manufactured by Nippon Shokubai Co., Ltd. Also product name).
The content or addition amount of the compound having an oxazoline group is preferably 0 as a solid content with respect to 100 parts by mass of the resin in the resin dispersion from the viewpoint of enhancing the crosslinking reactivity with the resin and improving the productivity. 0.1-30 parts by mass, more preferably 0.5-20 parts by mass, and even more preferably 1-10 parts by mass.

  By adding and mixing a compound having an oxazoline group, the polyester resin contained in the resin particles (A) dispersed in the resin dispersion is crosslinked. The temperature at the time of mixing becomes like this. Preferably it is 60-100 degreeC, More preferably, it is 70-98 degreeC. The presence of the crosslink can be confirmed by the amide group.

[Releasing agent particles]
The release agent particles contain the aforementioned release agent. Although this release agent particle may consist only of a release agent, it is preferable to contain surfactant from a viewpoint of preventing aggregation. In the case of using the surfactant, the content is preferably 0.01 to 10 parts by mass with respect to 100 parts by mass of the release agent, from the viewpoint of aggregation properties and chargeability of the obtained toner. Part by mass is more preferable. The lower limit of the content of the release agent in the release agent particles is preferably 90% by mass, more preferably 95% by mass, and the upper limit is preferably 99.99% by mass, more preferably. It is 99.9 mass%.
The volume median particle size of the release agent particles is preferably 0.1 to 1 μm, more preferably 0.1 to 0.7 μm, and more preferably 0.1 to 0 μm from the viewpoint of improving the chargeability of the toner and preventing hot offset. More preferably, it is 5 μm.
The CV value of the release agent particles is preferably 15 to 50%, more preferably 15 to 40%, and still more preferably 15 to 35%, from the viewpoint of improving the chargeability of the toner.

The release agent particles are preferably obtained as a dispersion of release agent particles by dispersing the release agent in an aqueous medium.
The dispersion of the release agent particles is preferably obtained by dispersing the release agent and the aqueous medium using a disperser in the presence of a surfactant at a temperature equal to or higher than the melting point of the release agent. As the disperser to be used, a homogenizer, an ultrasonic disperser or the like is preferable.
As the aqueous medium used in the present production, those used when obtaining a resin mixture are preferably used.
As the surfactant, an anionic surfactant is preferable, polycarboxylate and alkenyl succinate are more preferable, and polycarboxylate is more preferable.
Examples of polycarboxylates include polyacrylates, acrylic acid-maleic acid copolymer salts, polymaleic acid salts, and the like, from the viewpoint of enhancing cohesiveness during toner preparation, and acrylic acid-maleic acid copolymers. The salt of is preferred. As the salt, an alkali metal salt is preferable, and a sodium salt is preferable.
The sodium salt is preferably sodium polyacrylate, sodium salt of acrylic acid-maleic acid copolymer, sodium polymaleate or the like, and from the same viewpoint, sodium salt of acrylic acid-maleic acid copolymer is more preferable.

[Resin particles (C)]
In the present invention, the resin particles (C) are used in the step (2) and contain an amorphous polyester (c) from the viewpoint of improving the low-temperature fixability and heat-resistant storage stability of the toner.
The amount of the amorphous polyester (c) in the resin particles (C) is preferably 50 to 100% by mass, more preferably 80 in the resin constituting the resin particles (C), from the viewpoint of improving the low-temperature fixability of the toner. -100 mass%, More preferably, it is 90-100 mass%, More preferably, it is substantially 100 mass%, More preferably, it is 100 mass%.

The resin particles (C) are preferably produced by a method in which a resin containing amorphous polyester (c) is dispersed in an aqueous medium to obtain a dispersion containing resin particles (C). In the present specification, “resin containing amorphous polyester (c)” refers to a mixture obtained by mixing amorphous polyester (c) and another resin.
As with the resin particles (A), the dispersion is obtained by adding a resin or the like to an aqueous medium and dispersing using a disperser, or by gradually adding the aqueous medium to the resin or the like and emulsifying the emulsion. From the viewpoint of improving the low-temperature fixability of the obtained toner, the phase inversion emulsification method is preferable.

First, a resin containing amorphous polyester (c), an aqueous alkali solution, and the like are melted and mixed to obtain a resin mixture. In mixing, it is preferable to add a surfactant from the viewpoint of improving the emulsion stability of the resin.
Examples of the alkali in the alkaline aqueous solution include hydroxides of alkali metals such as potassium hydroxide and sodium hydroxide, and ammonia. From the viewpoint of improving the dispersibility of the resin, potassium hydroxide and sodium hydroxide are preferable. . Moreover, 1-30 mass% is preferable, as for the density | concentration of the alkali in alkaline aqueous solution, 1-25 mass% is more preferable, and 1.5-20 mass% is still more preferable.

The type of the surfactant is as described in the above-mentioned “Production of the resin particles (A)”, and in particular, the mass ratio of the nonionic surfactant to the anionic surfactant (nonionic surfactant / Anionic surfactant) 0.5 to 5 is preferably used in combination. The nonionic surfactant is preferably polyoxyethylene alkyl ether, and the anionic surfactant is preferably dodecylbenzene sulfonate, and more preferably used in combination.
The content of the surfactant is preferably 20 parts by mass or less, more preferably 15 parts by mass or less, and still more preferably 0.1 to 10 parts by mass with respect to 100 parts by mass of the resin constituting the resin particles (C). 0.5-10 mass parts is still more preferable.
As a method for obtaining the resin mixture, in addition to the amorphous polyester (c), an arbitrary resin such as crystalline polyester (d), an aqueous alkali solution, preferably a surfactant is put in a container and stirred with a stirrer. A method of melting and uniformly mixing the resin is preferable.
The temperature at which the resin is melted and mixed is preferably equal to or higher than the glass transition point of the amorphous polyester (c).

Next, an aqueous medium is added to the resin mixture and phase inversion is performed to obtain a dispersion containing resin particles (C).
About the kind and content of an aqueous medium, it is as having demonstrated in above-mentioned "manufacture of the resin particle (A)."

From the viewpoint of obtaining homogeneous resin particles, the temperature at which the aqueous medium is added is preferably not less than the glass transition point of the amorphous polyester (c), and more preferably not less than the melting point of the crystalline polyester (d).
From the viewpoint of obtaining resin particles having a small particle size, the addition rate of the aqueous medium is 0.1 to 50 parts by mass / 100 parts by mass of the resin constituting the resin particles (C) until the phase inversion is completed. Preferably, it is 0.1 to 30 parts by weight / minute, more preferably 0.5 to 10 parts by weight / minute, and 0.5 to 5 parts by weight / minute. Is more preferable. There is no restriction | limiting in the addition rate of the aqueous medium after phase inversion.
The use amount of the aqueous medium is preferably 100 to 2000 parts by mass, and 150 to 1500 parts by mass with respect to 100 parts by mass of the resin constituting the resin particles (C) from the viewpoint of obtaining uniform aggregated particles in the subsequent aggregation step. More preferred is 150 to 500 parts by mass. From the viewpoint of improving the stability of the resulting resin particle dispersion, the solid content concentration is preferably 7 to 50% by mass, more preferably 10 to 40% by mass, still more preferably 20 to 40% by mass, and still more preferably. It is 25-35 mass%. In addition, solid content is the total amount of non-volatile components, such as resin and surfactant.

The volume median particle size of the resin particles (C) in the obtained dispersion is preferably 0.02 to 2 μm. From the viewpoint of obtaining a toner capable of obtaining a high-quality image, 0.02 to 1.5 μm is preferable, 0.05 to 1 μm is more preferable, and 0.05 to 0.5 μm is still more preferable.
Further, the coefficient of variation (CV value) (%) of the particle size distribution of the resin particles is preferably 40% or less, more preferably 35% or less, and more preferably 30% from the viewpoint of obtaining a toner capable of obtaining a high-quality image. The following is more preferable, and 28% or less is more preferable.

[Manufacture of black toner for developing electrostatic images]
<Step (1)>
Step (1) is a step of obtaining aggregated particles (1) by aggregating resin particles (A) containing amorphous polyester (a), carbon black, and copper phthalocyanine having an anionic group in an aqueous medium. is there.
In this step, it is preferable to use release agent particles in combination. That is, it is preferable to agglomerate release agent particles containing a release agent together with the resin particles (A) to obtain aggregated particles (1).
In this step, first, the resin particles (A) and arbitrary release agent particles are mixed in an aqueous medium to obtain a mixed dispersion.
There is no restriction | limiting in order of mixing, You may add any in order and may add simultaneously.

In the mixed dispersion, the resin particles (A) are preferably 10 to 40 parts by mass, and more preferably 20 to 30 parts by mass. The aqueous medium is preferably 60 to 90 parts by mass, and more preferably 70 to 80 parts by mass.
In addition, the carbon black is preferably 1 to 20 parts by mass, and 3 to 15 parts by mass with respect to 100 parts by mass of the resin constituting the resin particles (A) from the viewpoint of improving the image density of the printed matter obtained using the toner. Part is more preferred. From the viewpoint of improving the releasability and chargeability of the toner, the release agent particles are preferably 1 to 20 parts by mass, more preferably 2 to 15 parts by mass with respect to a total of 100 parts by mass of the resin and the pigment.
The mixing temperature is preferably 0 to 40 ° C. from the viewpoint of controlling aggregation and obtaining aggregated particles having a target particle size.

Next, the particles in the mixed dispersion are aggregated to obtain a dispersion of aggregated particles (1). It is preferable to add a flocculant for efficient aggregation.
The aggregating agent is preferably an electrolyte, and more preferably a salt, for the purpose of obtaining a toner having a target particle size while preventing excessive aggregation. The valence is preferably 1 to 5, more preferably 1 to 2, and even more preferably 1. That is, a monovalent salt is preferable.
As the monovalent salt, an ammonium salt is preferable.
Specific examples of flocculants include quaternary salt cationic surfactants, organic flocculants such as polyethyleneimine; inorganic flocculants such as inorganic metal salts, inorganic ammonium salts, and bivalent metal complexes. It is done.
Examples of the inorganic metal salt include metal salts such as sodium sulfate, sodium chloride, calcium chloride and calcium nitrate, and inorganic metal salt polymers such as polyaluminum chloride and polyaluminum hydroxide. Examples of the inorganic ammonium salt include ammonium sulfate, ammonium chloride, ammonium nitrate and the like, and ammonium sulfate is more preferable.
The amount of the flocculant used is preferably 50 parts by mass or less, more preferably 40 parts by mass or less, and still more preferably from 100 parts by mass of the resin constituting the resin particles (A) from the viewpoint of improving the chargeability of the toner. Is 30 parts by mass or less. Further, from the viewpoint of controlling the aggregation of the resin particles to obtain a target particle size, the resin particles (A) are preferably 1 part by mass or more, more preferably 3 parts by mass or more, with respect to 100 parts by mass of the resin. More preferably, it is 5 parts by mass or more. Considering the above points, the amount of monovalent salt used is preferably 1 to 50 parts by mass, more preferably 3 to 40 parts by mass, with respect to 100 parts by mass of the resin constituting the resin particles (A). More preferably, it is 5-30 mass parts.

As an aggregating method, an aggregating agent is preferably added dropwise as an aqueous solution to a container containing a mixed dispersion. The flocculant may be added at one time, or may be added intermittently or continuously. However, it is preferable to perform sufficient stirring at the time of addition and after completion of the addition. From the viewpoint of controlling the aggregation to obtain a desired particle size and shortening the toner production time, the dropping time of the aggregating agent is preferably 1 to 120 minutes. Moreover, 0-50 degreeC is preferable from a viewpoint of dripping temperature controlling aggregation and obtaining the target particle size.
Further, from the viewpoint of promoting aggregation and obtaining aggregated particles having a target particle size and particle size distribution, it is preferable to increase the temperature of the dispersion after adding the aggregating agent. As temperature to maintain, 50-70 degreeC is preferable.
The volume median particle size of the obtained aggregated particles (1) is preferably 1 to 10 μm, more preferably 2 to 9 μm, and further preferably 3 to 6 μm, from the viewpoint of suppressing toner scattering. The CV value is preferably 30% or less, more preferably 28% or less, and still more preferably 25% or less.

<Step (2)>
Step (2): In this step, the resin particles (C) containing the amorphous polyester (c) are aggregated on the surface of the aggregated particles (1) to obtain aggregated particles (2).
In this step, the dispersion of resin particles (C) is added to the dispersion of aggregated particles (1) obtained in step (1), and the resin particles (C) are further adhered to the aggregated particles (1). Aggregation is preferably performed to obtain aggregated particles (2).

Before adding the dispersion liquid (resin particle (C) dispersion liquid) containing the resin particles (C) to the dispersion liquid (aggregated particle (1) dispersion liquid) containing the aggregated particles (1), the aggregated particle (1) An aqueous medium may be added to the dispersion for dilution, and an aqueous medium is preferably added. By adding an aqueous medium to obtain a predetermined coagulant concentration, the resin particles (C) can be more uniformly adhered and aggregated on the aggregated particles (1).
When the resin particle (C) dispersion is added to the aggregated particle (1) dispersion, the aggregating agent may be used in order to efficiently attach the resin particle (C) to the aggregated particle (1).
As a preferable addition method in the case of adding the resin particle (C) dispersion to the aggregated particle (1) dispersion, a method of simultaneously adding the coagulant and the resin particle (C) dispersion, the coagulant and the resin particle (C ) A method of alternately adding the dispersion liquid, and a method of adding the resin particle (C) dispersion liquid while gradually raising the temperature of the aggregated particle (1) dispersion liquid. By doing in this way, the cohesiveness fall of the coagulated particle (1) and the resin particle (C) by the coagulant | flocculant density | concentration fall can be prevented. From the viewpoint of toner productivity and manufacturing simplicity, it is preferable to add the resin particle (C) dispersion while gradually raising the temperature of the aggregated particle (1) dispersion.

  The temperature in the system in this step is 5 ° C. from the melting point of the crystalline polyester (b) contained in the resin particles (A) from the viewpoint of improving the low-temperature fixability and heat-resistant storage stability of the toner and suppressing the scattering of the toner. It is preferably lower than the glass transition point of the amorphous polyester (a) by 3 ° C. or more, more preferably 5 ° C. or more. When the aggregated particles (2) are produced in this temperature range, the low-temperature fixability and heat-resistant storage stability of the obtained toner are improved. Although the reason is not certain, it is because the generation of coarse particles is suppressed and the crystallinity of the crystalline polyester (b) can be maintained because fusion of the aggregated particles (2) does not occur. Conceivable.

The amount of the resin particles (C) added is such that the mass ratio of the resin particles (C) to the resin particles (A) (resin particles) is improved from the viewpoint of improving low-temperature fixability and heat-resistant storage stability of the toner and suppressing toner scattering. The amount of (C) / resin particles (A)) is preferably 0.1 to 0.9, more preferably 0.1 to 0.5, and still more preferably 0.2 to 0.4.
Compared with the resin particles (A), by adding a small amount of the resin particles (C), the effect of the core portion of the toner of the present invention in which the crystalline polyester (b) and the amorphous polyester (a) are mixed is sufficiently obtained. And can improve heat-resistant storage stability.

  The resin particle (C) dispersion may be added continuously over a certain period of time, may be added at a time, or may be added in a plurality of divided portions. It is preferable to add them continuously or in several divided portions. By adding as described above, the resin particles (C) are likely to selectively adhere to the aggregated particles (1). Among these, it is preferable to add continuously over a certain time from the viewpoint of promoting selective adhesion and efficient production. The time for continuous addition is preferably 1 to 10 hours, more preferably 2 to 7 hours from the viewpoint of obtaining uniform aggregated particles (2) and shortening the production time.

The total amount of the resin particles (C) is added, and the aggregation is stopped when the toner particles grow to an appropriate particle size.
As a particle size for stopping the aggregation, the volume median particle size is preferably 1 to 10 μm, more preferably 2 to 10 μm, still more preferably 3 to 9 μm, and further preferably 4 to 6 μm.
Examples of the method for stopping the aggregation include a method of cooling the dispersion, a method of adding an aggregation stopper, and a method of diluting the dispersion. From the viewpoint of reliably preventing unnecessary aggregation, the aggregation stopper A method of stopping the aggregation by adding is preferable.
As the aggregation terminator, a surfactant is preferable, and an anionic surfactant is more preferable. Examples of the anionic surfactant include alkyl ether sulfates such as sodium alkyl ether sulfate, alkyl sulfates, and linear alkylbenzene sulfonates. The aggregation terminators can be used alone or in combination of two or more.
The addition amount of the aggregation terminator is preferably 0.1 to 15 parts by mass with respect to 100 parts by mass of the total amount of the resin in the system, from the viewpoint of the property of stopping aggregation and from the viewpoint of reducing residual toner. Preferably it is 0.1-10 mass parts, More preferably, it is 0.1-8 mass parts. The aggregation terminator is preferably added as an aqueous solution from the viewpoint of improving productivity.

  The volume median particle size of the agglomerated particles (2) obtained in the step (2) is preferably 1 to 10 μm, more preferably 2 to 10 μm, and more preferably 3 to 9 μm from the viewpoint of obtaining a high-quality printed material with toner. Is more preferable, and 4 to 6 μm is more preferable.

<Step (3)>
In step (3), the agglomerated particles (2) obtained in step (2) are held above the glass transition point of amorphous polyester (c), and resin particles containing amorphous polyester (c) (C) This is a step of obtaining core-shell particles fused with each other. In the aggregated particles (2), the particles that have been mainly physically attached and aggregated with each other are fused and integrated to form a core-shell. Particles are formed.

From the viewpoint of promoting fusion and improving toner productivity, in this step, the temperature is preferably at least the glass transition point of the amorphous polyester (c), more preferably at least 5 ° C. higher than the glass transition point. Hold on. From the viewpoint of improving the heat-resistant storage stability while maintaining the core-shell state of the toner and maintaining the low-temperature fixability, it is preferably maintained at a temperature below the melting point of the crystalline polyester (b) in this step.
Further, from the viewpoint of improving the low-temperature fixability of the toner, in this step, it is preferably maintained at a temperature not higher than the melting point of the release agent, more preferably not higher than 3 ° C., more preferably not higher than 5 ° C.
In this step, the temperature is preferably maintained at 55 to 85 ° C, more preferably 60 to 80 ° C, and still more preferably 65 to 75 ° C from the viewpoint of promoting particle fusion.
The holding time in this step is preferably 0.5 to 24 hours, more preferably 0.7 to 18 hours, from the viewpoint of improving particle fusing property, heat-resistant storage stability of toner, chargeability and toner productivity. More preferably, it is 1 to 12 hours.

From the viewpoint of obtaining a high-quality image, the volume-median particle size of the core-shell particles obtained in this step is preferably 2 to 10 μm, more preferably 2 to 8 μm, more preferably 2 to 7 μm, still more preferably 3 to 8 μm. More preferably, it is 4-6 micrometers.
The average particle size of the fused core-shell particles obtained in this step is preferably equal to or less than the average particle size of the aggregated particles (2). That is, in this step, it is preferable that the core shell particles do not aggregate and fuse.
The circularity of the core-shell aggregated particles is preferably from 0.93 to 0.98, more preferably from 0.93 to 0.975, from the viewpoint of obtaining a high-quality printed matter with the toner and further suppressing toner scattering.

<Post-processing process>
In the present invention, a post-treatment step may be performed after step (3), and it is preferable to obtain toner particles by isolating the core-shell particles.
Since the core-shell particles obtained in the step (3) are present in the aqueous medium, it is preferable to first perform solid-liquid separation. For solid-liquid separation, a suction filtration method or the like is preferably used.
It is preferable to perform washing after the solid-liquid separation. When a nonionic surfactant is used in the production of the resin particles (A) and (C), it is preferable to remove the added nonionic surfactant, so that it is aqueous below the cloud point of the nonionic surfactant. Washing with a solution is preferred. The washing is preferably performed a plurality of times.
Next, although it is preferable to dry, the temperature at the time of drying is preferably such that the temperature of the core-shell particle itself is 5 ° C. or more lower than the melting point of the crystalline polyester, and preferably 10 ° C. or more. More preferred. As a drying method, it is preferable to use a vibration type fluidized drying method, a spray drying method, a freeze drying method, a flash jet method, or the like. The water content after drying is preferably adjusted to 1.5% by mass or less, more preferably 1.0% by mass or less, from the viewpoint of suppressing toner scattering and improving the chargeability.

[Black toner for electrostatic image development]
<Toner>
Although the toner particles obtained by drying or the like can be used as they are as the toner of the present invention, it is preferable to use toner particles whose surfaces have been treated as described below as electrostatic charge image developing toner.
The softening point of the obtained toner is preferably 60 to 140 ° C., more preferably 60 to 130 ° C., and still more preferably 60 to 120 ° C. from the viewpoint of improving the low-temperature fixability of the toner. The glass transition point is preferably 30 to 80 ° C., more preferably 40 to 70 ° C., from the viewpoint of improving low-temperature fixability, durability and heat-resistant storage stability.
The volume-median particle size of the toner is preferably 1 to 10 μm, more preferably 2 to 8 μm, still more preferably 3 to 7 μm, and still more preferably 4 from the viewpoint of obtaining a high-quality printed matter with the toner and improving productivity. ~ 6 μm.
The CV value of the toner is preferably 30% or less, more preferably 27% or less, still more preferably 25% or less, and even more preferably 22% or less, from the viewpoint of obtaining a high-quality printed material and improving productivity.
The degree of circularity of the toner is preferably 0.93 to 0.98, and more preferably 0.93 to 0.975, from the viewpoint of suppressing toner scattering and improving cleaning properties.
BET specific surface area of the toner suppresses the scattering of the toner is preferably 1.2~2.5m ² / g from the viewpoint of improving the heat-resistant storage stability, more preferably 1.4~2.2m ² / g, 1 More preferably, it is 6 to 2.0 m ² / g.

<External additive>
In the black toner for developing an electrostatic charge image of the present invention, the toner particles can be used as the toner as they are, but it is preferable to use a toner obtained by adding a fluidizing agent or the like to the toner particle surface as an external additive. .
Examples of the external additive include hydrophobic silica, titanium oxide fine particles, alumina fine particles, cerium oxide fine particles, inorganic fine particles such as carbon black, and polymer fine particles such as polycarbonate, polymethyl methacrylate, and silicone resin. Among these, hydrophobic Silica is preferred.
When the surface treatment of toner particles is performed using an external additive, the amount of the external additive added is preferably 1 to 5 parts by mass, more preferably 2 to 4 parts by mass with respect to 100 parts by mass of the toner particles. .

  The black toner for developing an electrostatic charge image obtained by the present invention can be used as a one-component developer or mixed with a carrier and used as a two-component developer.

  In relation to the above-described embodiment, the present invention discloses the following method for producing an electrostatic image developing toner and electrostatic image developing toner.

<1> A method for producing a black toner for developing an electrostatic charge image, comprising the following steps (1) to (3).
Step (1): A step of obtaining aggregated particles (1) by aggregating resin particles (A) containing amorphous polyester (a), carbon black, and copper phthalocyanine having an anionic group in an aqueous medium. Step (2): Step of obtaining aggregated particles (2) by aggregating resin particles (C) containing amorphous polyester (c) on the surface of aggregated particles (1) Step (3): Aggregated particles (2 ) Is maintained above the glass transition point of the amorphous polyester (c) to obtain core-shell particles in which the resin particles (C) are fused.

<2> The copper phthalocyanine having an anionic group has a lower limit of preferably 0.1 parts by mass, more preferably 1 part by mass, still more preferably 5 parts by mass, and still more preferably 100 parts by mass of carbon black. The upper limit is preferably 30 parts by mass, more preferably 25 parts by mass, still more preferably 20 parts by mass, still more preferably 18 parts by mass, and preferably 0.1 to 30 parts by mass. More preferably, it is 1-25 mass parts, More preferably, it is 1-20 mass parts, More preferably, it is 5-20 mass parts, More preferably, it is 10-18 mass parts, <1> A method for producing a black toner for developing an electrostatic image as described in 1.
<3> The method for producing a black toner for developing an electrostatic charge image according to <1> or <2>, wherein the copper phthalocyanine having an anionic group is a copper phthalocyanine sulfonate.
<4> The method for producing a black toner for developing an electrostatic charge image according to <3>, wherein the copper phthalocyanine sulfonate is a tetraalkylammonium salt of copper phthalocyanine sulfonate.
<5> The content of carbon black in the resin particles (A) is preferably 1 part by mass, more preferably 3 parts by mass with respect to 100 parts by mass of the resin constituting the resin particles (A). More preferably, it is 5 parts by mass, the upper limit is preferably 20 parts by mass, more preferably 15 parts by mass, still more preferably 10 parts by mass, preferably 1 to 20 parts by mass. The method for producing a black toner for developing an electrostatic charge image according to any one of <1> to <4>, more preferably 3 to 15 parts by mass, and still more preferably 5 to 10 parts by mass.

<6> Any of <1> to <5>, wherein step (1) is a step of aggregating release agent particles containing a release agent together with resin particles (A) to obtain aggregated particles (1) A method for producing a black toner for developing electrostatic images according to claim 1.
<7> The method for producing a black toner for developing an electrostatic charge image according to any one of <1> to <6>, wherein the resin particles (A) contain the crystalline polyester (b).
<8> The method for producing a black toner for developing an electrostatic charge image according to <7>, wherein the crystalline polyester (b) has a melting point of 50 to 150 ° C, preferably 60 to 100 ° C, more preferably 70 to 90 ° C.
<9> The mass ratio of the crystalline polyester (b) and the amorphous polyester (a) is (b) / (a) = 5/95 or more and 50/50 or less, preferably teeth 5/95 or more and 40/60 or less. The electrostatic charge according to <7> or <8>, preferably from 10/90 to 40/60, more preferably from 10/90 to 30/70, and still more preferably from 15/85 to 20/80. A method for producing a black toner for image development.
<10> In step (3), the aggregated particles (2) are held at a temperature not lower than the glass transition point of the amorphous polyester (c) and lower than the melting point of the crystalline polyester (b). ) The method for producing a black toner for developing an electrostatic charge image according to any one of <7> to <9>, which is a step of obtaining core-shell particles fused with each other.

<11> In step (1), an aqueous medium is added to a resin mixture containing amorphous polyester (a), carbon black, and copper phthalocyanine having an anionic group to perform phase inversion emulsification, and resin particles (A The method for producing a black toner for developing an electrostatic charge image according to any one of <1> to <10>, wherein the resin particles (A) are aggregated to obtain aggregated particles (1).
<12> The amorphous polyester (a) is composed of an amorphous polyester (a-2) having a higher softening point than the amorphous polyesters (a-1) and (a-1), <1> to <11 The method for producing a black toner for developing an electrostatic image according to any one of the above.
<13> The softening point of the amorphous polyester (a-1) and the amorphous polyester (a-2) is 70 ° C. or more and 165 ° C. or less, and the amorphous polyester (a-1) and the amorphous polyester ( The difference in softening point of a-2) is preferably 5 ° C. or higher, more preferably 7 ° C. or higher, preferably 30 ° C. or lower, more preferably 20 ° C. or lower, preferably 5 ° C. The method for producing a black toner for developing an electrostatic charge image according to <12>, which is 30 ° C. or higher and more preferably 7 ° C. or higher and 20 ° C. or lower.
<14> The amorphous polyester (a-2) contains at least one selected from alkyl succinic acid having an alkyl group having 9 to 14 carbon atoms and alkenyl succinic acid having an alkenyl group having 9 to 14 carbon atoms. <12> or <13> The method for producing a black toner for developing an electrostatic charge image according to <12>, which is an amorphous polyester obtained by condensation polymerization of an acid component and an alcohol component.
<15> The number average molecular weight of the amorphous polyester (a) has a lower limit of preferably 1,000, more preferably 1,500, still more preferably 2,000, and preferably an upper limit. 50,000, more preferably 10,000, still more preferably 4,000, preferably 1,000 to 50,000, more preferably 1,500 to 10,000, The method for producing a black toner for developing an electrostatic charge image according to any one of <1> to <14>, preferably 2,000 to 4,000.

<16> An electrostatic charge image developing black toner obtained by the production method of <1> to <14>.
<17> Carbon black, copper phthalocyanine having an anionic group, amorphous polyester (a), crystalline polyester (b), a core containing a release agent, and a shell containing amorphous polyester (c) A black toner for developing an electrostatic charge image.

  Each property value of polyester, resin particles, toner, etc. was measured and evaluated by the following method.

[Acid value of polyester]
It measured according to JIS K0070. However, the measurement solvent was chloroform.

[Softening point, melting point and glass transition point of polyester and toner, crystallinity index]
(1) Softening point Using a flow tester (manufactured by Shimadzu Corporation, trade name: CFT-500D), a load of 1.96 MPa was applied by a plunger while heating a 1 g sample at a heating rate of 6 ° C / min. And extruded from a nozzle with a diameter of 1 mm and a length of 1 mm. The amount of flow tester drop by the flow tester was plotted against the temperature, and the temperature at which half the sample flowed out was taken as the softening point.

(2) Melting point and glass transition point Sample heated to 200 ° C. using a differential scanning calorimeter (manufactured by PerkinElmer, trade name: Pyris 6 DSC), and cooled to 0 ° C. at a temperature decreasing rate of 50 ° C./min. Was measured at a heating rate of 10 ° C./min. Among the observed endothermic peaks, the temperature of the peak having the maximum peak area was defined as the maximum endothermic temperature (1). In the case of crystalline polyester, the peak temperature was taken as the melting point. In the case of an amorphous polyester, when an endothermic peak is observed, the temperature of the peak is measured, and when a step is observed without a peak being observed, the tangent indicating the maximum slope of the curve of the step and the step The glass transition point was defined as the temperature at the intersection with the base line extension line on the high temperature side.

(3) Crystallinity Index Using a differential scanning calorimeter (manufactured by PerkinElmer, trade name: Pyris 6 DSC), a sample cooled from room temperature (20 ° C.) to 0 ° C. at a temperature decrease rate of 10 ° C./min is left still for 1 minute. Then, the temperature was raised to 180 ° C. at a temperature raising rate of 10 ° C./min. Of the observed peaks, the peak temperature with the maximum peak area is defined as the endothermic maximum peak temperature (2), and the crystallinity by (softening point (° C)) / (maximum endothermic peak temperature (2) (° C)). The index was determined.

[Volume Median Particle Size (D ₅₀ ), Volume Average Particle Size (D _v ), and Particle Size Distribution of Toner]
The volume median particle size of the toner was measured as follows.
Measuring instrument: Coulter Multisizer III (trade name, manufactured by Beckman Coulter)
・ Aperture diameter: 50μm
・ Analysis software: Multisizer III version 3.51 (trade name, manufactured by Beckman Coulter)
Electrolyte: Isoton II (trade name, manufactured by Beckman Coulter)
-Dispersion: Polyoxyethylene lauryl ether (manufactured by Kao Corporation, trade name: Emulgen 109P, HLB: 13.6) was dissolved in the electrolytic solution to obtain a dispersion having a concentration of 5% by mass.
-Dispersion condition: 10 mg of a toner measurement sample is added to 5 mL of the dispersion, and dispersed for 1 minute with an ultrasonic disperser, and then 25 mL of electrolyte is added, and further dispersed for 1 minute with an ultrasonic disperser. A sample dispersion was prepared.
Measurement conditions: The sample dispersion is added to 100 mL of the electrolytic solution to adjust the particle size of 30,000 particles to a concentration that can be measured in 20 seconds, and then 30,000 particles are measured and the particle size distribution thereof. From this, the volume median particle size (D ₅₀ ) was determined.
Further, as the particle size distribution, the CV value (%) was calculated from the volume average particle size (D _v ) and standard deviation displayed by the analysis software according to the following formula.
CV value (%) = (standard deviation of particle size distribution / volume average particle size (D _v )) × 100

[Number average molecular weight of polyester]
The molecular weight distribution was measured by gel permeation chromatography and the number average molecular weight was calculated by the following method.
(1) Preparation of sample solution Polyester was dissolved in chloroform so that the concentration was 0.5 g / 100 ml. Subsequently, this solution was filtered using a fluororesin filter having a pore size of 2 μm (manufactured by Sumitomo Electric Industries, Ltd., trade name: FP-200) to remove insoluble components to obtain a sample solution.
(2) Molecular weight distribution measurement Chloroform was allowed to flow as a lysis solution at a flow rate of 1 ml / min, and the column was stabilized in a constant temperature bath at 40 ° C. Measurement was performed by injecting 100 μl of the sample solution. The molecular weight of the sample was calculated based on a calibration curve prepared in advance. The calibration curve at this time includes several types of monodisperse polystyrene (monodisperse polystyrene manufactured by Tosoh Corporation; 2.63 × 10 ³ , 2.06 × 10 ⁴ , 1.02 × 10 ⁵ (weight average molecular weight), A monodisperse polystyrene manufactured by GL Sciences Inc .; 2.10 × 10 ³ , 7.00 × 10 ³ , 5.04 × 10 ⁴ (weight average molecular weight)) was used as a standard sample.
Measuring device: CO-8010 (trade name, manufactured by Tosoh Corporation)
Analytical column: GMHXL + G3000HXL (both trade names, manufactured by Tosoh Corporation)

[Volume Median Particle Size (D ₅₀ ), Volume Average Particle Size (D _v ), and Particle Size Distribution of Resin Particles and Release Agent Particles]
(1) Measuring device: Laser diffraction particle size measuring machine (Horiba, Ltd., trade name: LA-920)
(2) Measurement conditions: Distilled water was added to the measurement cell, and the volume-median particle size (D ₅₀ ) was measured at a concentration at which the absorbance was in an appropriate range.
Further, as the particle size distribution, the CV value (%) was calculated from the volume average particle size (D _v ) and standard deviation displayed by the particle size measuring instrument according to the following formula.
CV value (%) = (standard deviation of particle size distribution / volume average particle size (D _v )) × 100

[Solid content concentration of resin particle dispersion and release agent particle dispersion]
Using an infrared moisture meter (trade name: FD-230, manufactured by Ketto Scientific Laboratory), 5 g of a measurement sample was dried at a temperature of 150 ° C., measurement mode 96 (monitoring time 2.5 minutes, fluctuation range 0.05%) ) To measure the moisture percentage. The solid content concentration was calculated according to the following formula.
Solid content concentration (% by mass) = 100-M
M: moisture (%) = [(W−W ₀ ) / W] × 100
W: Sample mass before measurement (initial sample mass)
W ₀ : Mass of sample after measurement (absolute dry mass)

[BET specific surface area of toner particles]
A BET specific surface area was measured under the following conditions using Micromeritics FlowSorbIII (trade name, manufactured by Shimadzu Corporation).
Toner sample amount: 0.09 to 0.11 g
・ Deaeration condition: 40 ° C., 10 minutes ・ Adsorption gas: Nitrogen gas

[Toner fluidity evaluation]
Under an environment of a temperature of 25 ° C. and a relative humidity of 40 Rh%, a powder tester (manufactured by Hosokawa Micron Co., Ltd., product name) has three different sieve openings in the order of 150 μm in the upper stage, 75 μm in the middle stage, and 45 μm in the lower stage. Then, 2 g of toner was placed thereon and vibrated for 10 seconds, and the amount of toner remaining on each sieve was measured.
The measured toner mass was calculated by applying the following equation to obtain the degree of aggregation. The smaller the degree of aggregation, the better the fluidity.
Aggregation degree [%] = a + b + c
a = (Mass of residual toner on upper screen) / 2 [g] × 100
b = (middle stage residual toner mass) / 2 [g] × 100 × (3/5)
c = (lower stage residual toner mass) / 2 [g] × 100 × (1/5)

[Evaluation of heat-resistant storage stability of toner]
10 g of toner was placed in a 20 ml polybin and stored for 48 hours in an open environment in an environment of a temperature of 50 ° C. and a relative humidity of 40 Rh%. After storage, the degree of aggregation was measured by a powder tester (manufactured by Hosokawa Micron Corporation) by the following method.
Three different sieve openings are set on the powder tester's shaking table in the order of 250 μm in the upper stage, 150 μm in the middle stage, and 75 μm in the lower stage, and 2 g of toner is placed on it and shaken for 60 seconds. Was measured.
The measured toner mass was calculated by applying the following equation to obtain the degree of aggregation.
Aggregation degree [%] = a + b + c
a = (Mass of residual toner on upper screen) / 2 [g] × 100
b = (middle stage residual toner mass) / 2 [g] × 100 × (3/5)
c = (lower stage residual toner mass) / 2 [g] × 100 × (1/5)
The smaller the degree of aggregation, the better the heat resistant storage stability of the toner.

[Image density]
Using a commercially available printer (trade name: MicroLine 5400, manufactured by Oki Data Co., Ltd.) on high-quality paper (Fuji Xerox Co., Ltd., J paper A4 size), the toner adhesion amount on the paper is 0.42 to 0.48 mg. A solid image of / cm ² was output to obtain a printed matter.
30 sheets of high-quality paper (Oki Data Co., Ltd., Excellent White Paper A4 size) are laid under the printed material, and the reflected image density of the solid image portion of the printed material is measured by a colorimeter (trade name: SpectroEye, Gretag-Macbeth). , Light irradiation conditions: standard light source D50, observation field of view 2 °, density standard DINNB, absolute white standard). Values obtained by measuring three arbitrary points on the image were averaged to obtain an image density. The larger the value of the reflected image density, the better the image density.

[Production of polyester]
Production Example 1
(Production of amorphous polyester Y1)
The inside of a four-necked flask equipped with a nitrogen introduction tube, a dehydration tube, a stirrer, and a thermocouple was replaced with nitrogen, and 3374 g of polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, Polyoxyethylene (2.0) -2,2-bis (4-hydroxyphenyl) propane (33 g), terephthalic acid (672 g) and dibutyltin oxide (10 g) were added, and the temperature was raised to 230 ° C. with stirring in a nitrogen atmosphere. After maintaining the time, the pressure in the flask was further reduced and maintained at 8.3 kPa for 1 hour. Then, after cooling to 210 ° C. and returning to atmospheric pressure, 696 g of fumaric acid and 0.49 g of tert-butylcatechol were added and maintained at a temperature of 210 ° C. for 5 hours. The polyester resin Y1 was obtained by maintaining at 3 kPa for 4 hours. Table 1 shows the physical properties and the like.

Production Example 2
(Production of amorphous polyester Y2)
The inside of a four-necked flask equipped with a nitrogen introduction tube, a dehydration tube, a stirrer, and a thermocouple was replaced with nitrogen, and 1750 g of polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, A nitrogen atmosphere containing 1625 g of polyoxyethylene (2.0) -2,2-bis (4-hydroxyphenyl) propane, 1145 g of terephthalic acid, 161 g of dodecenyl succinic anhydride, 480 g of trimellitic anhydride, and 10 g of dibutyltin oxide Under stirring, the temperature was raised to 220 ° C. and maintained at 220 ° C. for 5 hours. After confirming that the softening point measured according to ASTM D36-86 reached 120 ° C., the temperature was lowered to stop the reaction. A polyester resin Y2 was obtained. Table 1 shows the physical properties and the like.

Production Example 3
(Production of crystalline polyester X1)
The inside of a four-necked flask equipped with a nitrogen introduction tube, a dehydration tube, a stirrer, and a thermocouple was purged with nitrogen, and 3936 g of 1,9-nonanediol and 4848 g of sebacic acid were added. While stirring, the temperature was raised to 140 ° C., maintained at 140 ° C. for 3 hours, and then heated from 140 ° C. to 200 ° C. over 10 hours. Thereafter, 50 g of tin dioctylate was added, and the mixture was further maintained at 200 ° C. for 1 hour, and then the pressure in the flask was lowered and maintained at 8.3 kPa for 4 hours to obtain crystalline polyester X1. Table 1 shows the physical properties and the like.

[Production of resin particles]
Production Example 4
(Production of resin particle dispersion 1)
In a 5 liter stainless steel flask equipped with a stirrer, 300 g of amorphous polyester Y1, 210 g of amorphous polyester Y2, 90 g of crystalline polyester X1, 59 g of carbon black (trade name: REAGAL330R, manufactured by Cabot Corporation), Copper phthalocyanine sulfonate (Solsperse 5000, manufactured by Lubrizol) 3.0 g, sodium dodecylbenzenesulfonate 15% by weight aqueous solution (trade name: Neoperex G-15, anionic surfactant) 80% by weight 0.0 g, polyoxyethylene lauryl ether (manufactured by Kao Corporation, trade name: Emulgen 150, nonionic surfactant) 8.5 g, and 58.5% by weight potassium hydroxide aqueous solution 278.5 g, Heat to 95 ° C to melt, mix at 95 ° C for 2 hours, mix Was obtained fat (step (1)).
Next, while maintaining the temperature of the system at 95 ° C., 1222 g of deionized water was added dropwise at a rate of 6 g / min while stirring to obtain an emulsion. The obtained emulsion was cooled and added with 23 g of an oxazoline group-containing polymer aqueous solution (manufactured by Nippon Shokubai Co., Ltd., trade name: Epocross WS-700, nonvolatile content 25 mass%, acrylic main chain) while stirring at 25 ° C. Then, the temperature was raised to 95 ° C. and held at 95 ° C. for 1 hour. Next, it was cooled to 25 ° C., and the resulting dispersion was passed through a 200 mesh (mesh opening 105 μm) wire mesh to obtain a resin particle dispersion 1.
The solid content concentration of the resin particle dispersion 1 was 31%, the volume median particle size (D ₅₀ ) of the resin particles in the resin particle dispersion 1 was 172 nm, and the CV value was 30%.

Production Examples 5-11
(Production of resin particle dispersions 2 to 8)
Resin Particle Dispersion Liquid 2 ~ 8 was obtained. Table 2 shows the physical properties and the like.

Production Example 12
(Production of resin particle dispersion 9)
In a flask equipped with a stirrer, 390 g of amorphous polyester Y1, 210 g of amorphous polyester Y2, polyoxyethylene alkyl ether (nonionic surfactant, trade name: Emulgen 430, manufactured by Kao Corporation) 0 g, 15 mass% sodium dodecylbenzenesulfonate aqueous solution (anionic surfactant, trade name: Neoperex G-15, manufactured by Kao Corporation) 20 g and 52.8 mass% potassium hydroxide 292.8 g were added and stirred. The mixture was heated to 95 ° C. and melted, and mixed at 95 ° C. for 2 hours to obtain a resin mixture.
Next, 1138 g of deionized water was added dropwise at a rate of 6 g / min while stirring to obtain an emulsion. Next, the obtained emulsion was cooled to 25 ° C., passed through a 200-mesh wire mesh, deionized water was added to adjust the solid content to 28% by mass, and a resin particle dispersion 9 was obtained. Table 2 shows the physical properties and the like.

[Manufacture of release agent particles]
Production Example 13
(Production of release agent particle dispersion)
2. In a 1 liter beaker, 200 g of deionized water and an aqueous solution of sodium acrylate-sodium maleate copolymer as a sodium polycarboxylate aqueous solution (trade name: Poise 521, effective concentration 40% by mass, manufactured by Kao Corporation) After 8 g was dissolved, 5 g of carnauba wax (manufactured by Hiroyuki Kato, product name: carnauba wax No. 1, melting point 83 ° C.) and paraffin wax (manufactured by Nippon Seiki Co., Ltd., product name: HNP) −9, melting point 75 ° C.) 45 g was added, and the mixture was melted while maintaining the temperature at 90 to 95 ° C. to obtain a molten mixture in which carnauba wax and paraffin wax were melted together.
The aqueous solution containing the obtained molten mixture was further subjected to a dispersion treatment for 30 minutes with an ultrasonic homogenizer (manufactured by Nippon Seiki Co., Ltd., trade name: US-600T) while maintaining the temperature at 90 to 95 ° C. Then, ion-exchanged water was added thereto to adjust the release agent solid content to 20% by mass to obtain a release agent particle dispersion.

[Production of toner]
Example 1
(Preparation of black toner 1)
In a 5 liter four-necked flask equipped with a dehydrating tube, a stirrer and a thermocouple, 250 g of resin particle dispersion 1, 54 g of deionized water, and 18 g of the release agent particle dispersion obtained in Production Example 13 are placed. And mixed at 25 ° C. Next, with stirring at 25 ° C., an aqueous solution in which 20.1 g of ammonium sulfate was dissolved in 196 g of deionized water was dropped into this mixture over 30 minutes. Subsequently, the obtained mixed liquid was heated to 58 ° C. and maintained at 58 ° C. to obtain a dispersion (a) containing aggregated particles (1) having a volume-median particle size of 4.6 μm.
Subsequently, after the dispersion (a) was adjusted to 50 ° C., a mixed liquid obtained by mixing 70 g of the resin particle dispersion 9 and 22 g of deionized water was dropped into the dispersion (a) over 180 minutes. In this step, the dispersion containing the aggregated particles was carried out while increasing the temperature from 50 ° C. to 1 ° C./hour. As a result, a dispersion containing aggregated particles (2) having a volume median particle size of 5.0 μm was obtained.
After adding an aqueous solution obtained by mixing 15.6 g of sodium polyoxyethylene lauryl ether sulfate (trade name: EMAL E27C, solid content: 28% by mass) and 1231 g of deionized water to the obtained dispersion. The temperature was raised to 68 ° C. over 2 hours and held for 1 hour to obtain fused particles having a volume median particle size of 4.9 μm. Then, it cooled to 25 degreeC.
The obtained fused particles were filtered, dried, and washed to obtain toner particles. To 100 parts by mass of the toner particles, hydrophobic silica (manufactured by Nippon Aerosil Co., Ltd., trade name: RY50, number average particle size; 0.04 μm), 2.5 parts by mass, hydrophobic silica (manufactured by Cabot Corporation, product) Name: Cabo Seal TS720, number average particle size; 0.012 μm) 1.0 part by mass was externally added with a Henschel mixer and passed through a 150 mesh sieve to obtain black toner 1.

Examples 2-5 and Comparative Examples 1-3
(Preparation of black toners 2 to 8)
Black toners 2 to 8 were obtained in the same manner as in Example 1 except that the resin particle dispersion 1 was changed to the resin particle dispersion shown in Table 3 in Example 1. Table 3 shows the physical properties and evaluation of the toner.

  From Table 3, the black toners 1 to 5 for developing electrostatic images of the examples all have excellent fluidity and heat-resistant storage stability as compared with the black toners 6 to 8 for developing electrostatic images of the comparative examples. It can be seen that the image density is also excellent.

  The electrostatic charge image developing black toner obtained by the production method of the present invention has good fluidity and heat-resistant storage stability and excellent image density, and therefore can be suitably used as a toner used in electrophotography. According to the method of the present invention, a toner having such characteristics can be produced efficiently.

Claims (16)

A method for producing a black toner for developing an electrostatic charge image, comprising the following steps (1) to (3):
Step (1): A step of obtaining aggregated particles (1) by aggregating resin particles (A) containing amorphous polyester (a), carbon black, and copper phthalocyanine having an anionic group in an aqueous medium. Step (2): Step of obtaining aggregated particles (2) by aggregating resin particles (C) containing amorphous polyester (c) on the surface of aggregated particles (1) Step (3): Aggregated particles (2 ) Is maintained above the glass transition point of the amorphous polyester (c) to obtain core-shell particles in which the resin particles (C) are fused.   2. The method for producing a black toner for developing an electrostatic charge image according to claim 1, wherein the copper phthalocyanine having an anionic group is 1 part by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the carbon black.   The method for producing a black toner for developing an electrostatic charge image according to claim 1 or 2, wherein the copper phthalocyanine having an anionic group is copper phthalocyanine sulfonate.   The method for producing a black toner for developing an electrostatic charge image according to claim 3, wherein the copper phthalocyanine sulfonate is a tetraalkylammonium salt of copper phthalocyanine sulfonate.   The content of carbon black in the resin particles (A) is 1 part by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the resin constituting the resin particles (A). Of producing a black toner for developing an electrostatic image.   The process according to any one of claims 1 to 5, wherein the step (1) is a step of aggregating release agent particles containing a release agent together with the resin particles (A) to obtain aggregated particles (1). A method for producing a black toner for developing a charge image.   The method for producing a black toner for developing an electrostatic charge image according to claim 1, wherein the resin particles (A) contain the crystalline polyester (b).   The method for producing a black toner for developing an electrostatic charge image according to claim 7, wherein the melting point of the crystalline polyester (b) is 70 ° C or higher and 90 ° C or lower.   The electrostatic charge image developing according to claim 7 or 8, wherein the mass ratio of the crystalline polyester (b) and the amorphous polyester (a) is (b) / (a) = 10/90 or more and 40/60 or less. Black toner manufacturing method.   In step (3), the aggregated particles (2) are held at a temperature not lower than the glass transition point of the amorphous polyester (c) and lower than the melting point of the crystalline polyester (b), so that the resin particles (C) are The method for producing a black toner for developing an electrostatic charge image according to any one of claims 7 to 9, which is a step of obtaining fused core-shell particles.   In step (1), an aqueous medium is added to a resin mixture containing amorphous polyester (a), carbon black, and copper phthalocyanine having an anionic group, and phase inversion emulsification is performed to obtain resin particles (A). The method for producing a black toner for developing an electrostatic charge image according to any one of claims 1 to 10, wherein the resin particles (A) are aggregated to obtain aggregated particles (1).   The amorphous polyester (a) is composed of an amorphous polyester (a-2) having a higher softening point than the amorphous polyesters (a-1) and (a-1). A method for producing the black toner for developing an electrostatic charge image according to claim 1.   The softening points of the amorphous polyester (a-1) and the amorphous polyester (a-2) are 70 ° C. or higher and 165 ° C. or lower, and the amorphous polyester (a-1) and the amorphous polyester (a-2) The method for producing a black toner for developing an electrostatic charge image according to claim 12, wherein the difference in softening point is 5 ° C. or more and 30 ° C. or less.   An acid component in which the amorphous polyester (a-2) contains at least one selected from alkyl succinic acid having an alkyl group having 9 to 14 carbon atoms and alkenyl succinic acid having an alkenyl group having 9 to 14 carbon atoms; The method for producing a black toner for developing an electrostatic charge image according to claim 12 or 13, which is an amorphous polyester obtained by condensation polymerization with an alcohol component.   A black toner for developing an electrostatic image obtained by the production method according to claim 1.   Carbon black, copper phthalocyanine having an anionic group, amorphous polyester (a), crystalline polyester (b), a core containing a release agent, and a shell containing amorphous polyester (c), Black toner for developing electrostatic images.