JP5833913B2 - Method for producing toner for developing electrostatic image - Google Patents

Description

  The present invention relates to a 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.
Corresponding to high image quality, a method of obtaining a toner having a narrow particle size distribution and a small particle size is obtained by aggregating and fusing fine resin particles in an aqueous medium to obtain a toner. A toner is manufactured by an aggregation method or an aggregation fusion method. In particular, attempts have been made to use a mixture of a plurality of types of resins in order to improve thermal characteristics such as fixability and offset resistance.

For example, Patent Document 1 discloses an amorphous polyester having 2.0 to 12.0 mol% of a structural unit derived from a trivalent or higher carboxylic acid and crystallinity for the purpose of improving low-temperature fixability and hot offset resistance. A step of emulsifying a raw material polyester containing polyester in an aqueous medium, or after mixing the raw material polyester with an organic solvent, an aqueous medium is added and emulsified to obtain a polyester particle dispersion, and the polyester particle dispersion is obtained. An electrophotographic toner obtained by aggregation and coalescence is disclosed.
Patent Document 2 discloses a toner formed by agglomerating resin particles in a liquid medium for the purpose of improving fixing strength, offset resistance, and heat-resistant storage stability. The toner includes a radical polymer resin, a colorant, and the like. And a toner inner layer containing a release agent, and a toner outer layer containing a grafted polyester resin formed by graft polymerization of a radical polymerizable monomer on a polyester having an unsaturated bond in the main chain at the outer edge. Toner is disclosed.
Patent Document 3 discloses that a polyhydric alcohol and an unsaturated polycarboxylic acid are condensed in order to eliminate offset and excessive gloss and to obtain a toner that does not have toner peeling at the crease portion, that is, insufficient fixing strength. A step of dispersing a polyester resin in an aqueous medium to prepare a polyester resin particle dispersion, and after adding a vinyl polymerizable monomer and a radical polymerization initiator to the polyester resin particle dispersion, a radical polymerization reaction is performed, and a polyester is obtained. A step of preparing a dispersion of resin particles made of a resin in which a vinyl polymerizable monomer is reacted with a resin, a resin particle made of a resin in which a vinyl polymerizable monomer is reacted with the polyester resin, and a dispersion of colorant particles And a step of agglomerating the resin particles and the colorant particles to form toner particles. .

International Publication No. 2010/27071 JP 2006-215312 A JP 2011-95736 A

In order to reduce power consumption during printing and to support high-speed printing, fixability at low temperatures is required, and in order to suppress high temperature offset, fixability is also required at high temperatures. Thus, a toner having a wide fixable area is desired.
By using a release agent in the toner, the fixing temperature region of the obtained toner can be adjusted from its melting characteristics. However, since the properties of the release agent change abruptly in the vicinity of the melting point, it is difficult to ensure the fixability in both low and high temperature ranges. On the other hand, as disclosed in Patent Document 2, a contrivance such as providing a toner outer layer has been made, but it is still insufficient. In addition, when a release agent having a low melting point is used in order to ensure fixing property at a low temperature, there is also a problem that the storage stability of the toner is lowered.
Further, in the aggregation and coalescence method (aggregation fusion method) as disclosed in Patent Documents 1 to 3, the charge amount of the obtained toner, particularly the high temperature and the high temperature, may be because of having polyester as a hydrophilic component. A decrease in charge amount in a wet environment becomes a problem.
An object of the present invention is to provide a toner for developing an electrostatic charge image that has both a wide fixable area and storage stability and is excellent in charge retention performance in a high-temperature and high-humidity environment, and a method for producing the same.

  The present inventors have found that the factors affecting the fixable area, storage stability, and charge retention performance in a high-temperature and high-humidity environment are the resin on the surface layer constituting the toner, the resin in the interior, and their relationship. I thought and examined it. As a result, a specific graft polymer composed of a crystalline polyester, an amorphous polyester and a release agent as a core portion, and a main chain segment composed of a polyester resin and a side chain segment composed of an addition polymerization resin is defined as a shell portion. It has been found that the toner for developing an electrostatic charge image has both a wide fixable area and storage stability and is excellent in charge retention performance in a high temperature and high humidity environment.

That is, the present invention provides the following [1] and [2].
[1] Crystalline polyester (a), amorphous polyester (b), core containing a release agent, main chain segment (A1) made of polyester resin, and side chain segment (A2) made of addition polymerization resin A toner for developing an electrostatic image containing a shell made of a graft polymer composed of a segment (A1) and a segment (A2) having a weight ratio of 95/5 to 60/40, wherein the segment (A1) As a raw material monomer from which the structural unit is derived, a dicarboxylic acid having a non-aromatic carbon-carbon unsaturated bond and having a carboxy group at both ends thereof exceeds 0 mol% in the carboxylic acid component of the segment (A1). An electrostatic image developing toner containing less than 20 mol%.
[2] The method for producing a toner for developing an electrostatic charge image according to [1], including the following steps (1) to (3).
Step (1): The resin particles (A) containing the crystalline polyester (a) and the amorphous polyester (b) and the release agent particles containing the release agent are aggregated to obtain aggregated particles (1). Step Step (2): A resin particle (C) made of a graft polymer composed of a main chain segment (A1) made of a polyester resin and a side chain segment (A2) made of an addition polymerization type resin is added to form aggregated particles ( Step 2) Step (3): Fusing the agglomerated particles (2) to obtain core-shell particles

  According to the present invention, it is possible to provide a toner for developing an electrostatic charge image that has both a wide fixable area and storage stability and is excellent in charge retention performance in a high-temperature and high-humidity environment, and a method for producing the same.

  The toner for developing an electrostatic charge image of the present invention comprises a core containing a crystalline polyester (a), an amorphous polyester (b) and a release agent, a main chain segment (A1) comprising a polyester resin, and an addition polymerization resin. An electrostatic charge image developing toner containing a shell made of a graft polymer composed of side chain segments (A2) comprising a weight ratio of segment (A1) to segment (A2) of 95/5 to 60/40 As a raw material monomer from which the structural unit of the segment (A1) is derived, a dicarboxylic acid having a non-aromatic carbon-carbon unsaturated bond and having a carboxy group at both ends is used as the carboxylic acid component of the segment (A1) Among them, it contains more than 0 mol% and less than 20 mol%.

The reason why the toner for developing an electrostatic charge image of the present invention has both a wide fixable region and storage stability and is excellent in charge retention performance in a high-temperature and high-humidity environment is not clear, but can be considered as follows.
The toner for developing an electrostatic image of the present invention has a core-shell structure, and contains a crystalline polyester (a), an amorphous polyester (b), and a release agent in the core portion. By having crystalline polyester, amorphous polyester and release agent in the core part, it melts sharply in each melting point region of crystalline polyester and release agent having crystallinity at the time of printing, and also amorphous at high temperature It is considered that polyester becomes a toner having a wide fixable region by preventing a sudden decrease in viscosity.
Further, the shell portion is composed of a graft polymer composed of a main chain segment (A1) made of a polyester resin and a side chain segment (A2) made of an addition polymerization resin, and the weight ratio of the segment (A1) to the segment (A2) is 95 / 5-60 / 40, a segment of dicarboxylic acid having a non-aromatic carbon-carbon unsaturated bond and having a carboxy group at both ends as a raw material monomer from which the constituent unit of segment (A1) is derived The carboxylic acid component (A1) contains more than 0 mol% and less than 20 mol%. That is, this graft polymer is a polyester resin in the main chain and an addition polymerization resin in the side chain, but contains a small amount of dicarboxylic acid having a non-aromatic carbon-carbon unsaturated bond that is the bonding point thereof. It is considered to have a long chain addition polymerization resin relatively sparsely.
It is considered that the main chain portion has high affinity with the core portion containing polyester and is firmly fused, and the side chain portion is easily oriented to the toner surface. In particular, since the side chain addition polymerization resin of the present invention is a long chain, it is possible to form a thick addition polymerization resin layer in the outermost layer, improving storage stability, and in a high temperature and high humidity environment. It is thought that it can have charge holding performance. In addition, it is considered that this graft polymer having a long-chain addition-polymerized resin side chain is likely to be entangled between molecules, or is considered to have appropriate elasticity in all temperature ranges. It is considered to be a toner having the same.
Hereinafter, each component and process used in the present invention will be described.

[core]
The core in the toner for developing an electrostatic charge image of the present invention contains a crystalline polyester (a), an amorphous polyester (b), and a release agent from the viewpoint of widening the fixable region of the toner.
[Crystalline polyester (a)]
In the present invention, the crystalline polyester is defined by the ratio between the softening point and the maximum endothermic peak temperature by a differential scanning calorimeter (DSC), (softening point (° C.)) / (Maximum endothermic peak temperature (° C.)). The crystallinity index is 0.6 to 1.4, and from the viewpoint of low-temperature fixability of the toner, 0.8 to 1.3 is preferable, and 0.9 to 1.2 is more preferable. 1.0 to 1.2 are more preferable.
The crystalline polyester (a) preferably has an acid group at the molecular end from the viewpoint of facilitating emulsification of the resin particle dispersion during toner production and enhancing dispersion stability. Examples of the acid group include a carboxyl group, a sulfonic acid group, a phosphonic acid group, and a sulfinic acid. Among these, a carboxyl group is preferable from the viewpoint of achieving both the dispersibility of the resin and the storage stability of the obtained toner.

The melting point of the crystalline polyester (a) is preferably from 50 to 150 ° C., more preferably from 55 to 130 ° C., from the viewpoint of improving the toner fixable region, storage stability, and charge holding performance in a high temperature and high humidity environment. Preferably, 60 to 90 ° C is more preferable, and 60 to 80 ° C is particularly preferable.
From the same viewpoint, the softening point of the crystalline polyester (a) is preferably 50 to 140 ° C, more preferably 55 to 130 ° C, still more preferably 60 to 110 ° C, and particularly preferably 60 to 85 ° C.
The number average molecular weight of the crystalline polyester (a) is preferably 1,500 to 50,000, more preferably 2,000 to 10,000, from the viewpoint of improving the fixable region and storage stability of the toner. 000 to 5,000 are more preferable.
The acid value of the crystalline polyester (a) is preferably 5 to 30 mgKOH / g, more preferably 10 to 27 mgKOH / g, from the viewpoint of improving the dispersion stability and charge holding performance of the resin particle dispersion of the toner. 25 mgKOH / g is more preferable, 15-25 mgKOH / g is still more preferable, and 15-22 mgKOH / g is still more preferable.
In addition, crystalline polyester (a) 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 (a) are determined by the methods described in the examples. When two or more kinds are used in combination, the melting point of the crystalline polyester (a) having the largest weight ratio in the crystalline polyester (a) contained in the obtained toner is the melting point of the crystalline polyester (a) in the present invention. The melting point. When all have the same ratio, the lowest value is set. A softening point and a number average molecular weight are calculated | required by the method as described in an Example using the mixture mixed by the ratio which uses all the crystalline polyester (a).

The crystalline polyester (a) can be produced by subjecting an acid component and an alcohol component to a polycondensation reaction. A catalyst can be preferably used in the polycondensation reaction.
Examples of the acid component include aliphatic dicarboxylic acid, alicyclic dicarboxylic acid, aromatic dicarboxylic acid, and trivalent or higher polyvalent carboxylic acid. Among them, toner fixable area, storage stability, and high temperature and high humidity environment An aliphatic dicarboxylic acid is preferable from the viewpoint of improving the charge retention performance below.
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 aliphatic dicarboxylic acid preferably has 2 to 18 carbon atoms, and more preferably 8 to 12 carbon atoms from the viewpoint of improving the toner fixable region, storage stability, and charge retention performance in a high-temperature and high-humidity environment.
Examples of the aliphatic carboxylic 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, etc. Among them, from the viewpoint of improving the toner fixable area, storage stability, and charge retention performance in a high temperature and high humidity environment, sebacic acid 1,12-dodecanedioic acid is preferred, and sebacic acid is more preferred.
Examples of the alicyclic dicarboxylic acid include cyclohexane dicarboxylic acid.
Examples of the aromatic dicarboxylic acid include phthalic acid, isophthalic acid, terephthalic acid and the like.
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 the alcohol component include aliphatic diols, aromatic diols, hydrogenated products of bisphenol A, and trihydric or higher polyhydric alcohols. Among them, the crystallization of polyester is promoted, and a toner fixable region is widened. In view of the above, an aliphatic diol is preferable.
Among the aliphatic diols, α, ω-alkanediol is preferable from the viewpoint of promoting crystallization of polyester and widening the fixable region of the toner.
The α, ω-alkanediol preferably has 2 to 18 carbon atoms and 4 to 12 carbon atoms from the viewpoint of improving the fixable region of the obtained toner, storage stability, and charge holding performance in a high temperature and high humidity environment. More preferably, C6-C12 is 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 the fixable region, storage stability, and charge retention performance in a high temperature and high humidity environment, 1,6-hexanediol and 1,9-nonanediol are preferable, and 1,9-nonanediol is more 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%.

  As a combination of an acid component and an alcohol component, there is a combination of an aliphatic dicarboxylic acid and an aliphatic diol from the viewpoint of improving low-temperature fixability and heat-resistant storage stability of the obtained toner and suppressing toner scattering (toner cloud). A combination of an α, ω-alkanediol having 2 to 18 carbon atoms and an aliphatic dicarboxylic acid having 8 to 12 carbon atoms is more preferable.

From the viewpoint of improving the efficiency of the condensation polymerization reaction, the catalyst is preferably a tin compound or a titanium compound, more preferably a tin compound, and further preferably di (2-ethylhexanoic acid) tin or 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.

  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 200 ° C. for 5 to 15 hours. Further, a method of obtaining a crystalline polyester by adding a catalyst and maintaining the reaction at 140 to 200 ° C. for 1 to 5 hours to proceed, reducing the pressure to 5.0 to 20 kPa, and maintaining it for 1 to 10 hours is preferable.

[Amorphous polyester (b)]
From the viewpoint of improving the adhesion to the shell portion and improving the toner fixable area, storage stability, and charge retention performance in a high-temperature and high-humidity environment, the core portion of the toner of the present invention has an amorphous polyester. (B) is contained. In the present invention, the amorphous polyester is a resin having a crystallinity index of more than 1.4 or less than 0.6.
The total amount of the crystalline polyester (a) and the amorphous polyester (b) in the core portion of the toner is from the viewpoint of improving the toner fixable region in the resin constituting the toner core portion, that is, the resin particles (A). Preferably it is 50-100 weight%, More preferably, it is 80-100 weight%, More preferably, it is 90-100 weight%, Most preferably, it is substantially 100 weight%. The weight ratio ((a) / (b)) between the crystalline polyester (a) and the amorphous polyester (b) in the core portion of the toner is the toner fixable area, storage stability, and high temperature and high humidity environment. From the standpoint of improving the charge retention performance at 5/95 to 50/50, preferably 5/95 to 30/70, more preferably 10/90 to 25/75, and 15/85 to 20/80 is even more preferable.

The amorphous polyester (b) can be produced by polycondensation reaction between an acid component and an alcohol component.
Examples of the acid component 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 more preferably used in combination.
As the dicarboxylic acid, a branched alkyl group having 9 to 14 carbon atoms is used from the viewpoint of improving the affinity with the crystalline polyester, and thus improving the fixing property of the toner, and improving the charge holding performance in a high temperature and high humidity environment. Alkyl succinic acid and / or alkenyl succinic acid having a branched alkenyl group having 9 to 14 carbon atoms and aromatic dicarboxylic acid are preferred, and alkyl succinic acid having a branched alkyl group having 9 to 14 carbon atoms and / or carbon number 9 More preferably, alkenyl succinic acid having -14 branched alkenyl groups and aromatic dicarboxylic acid are used in combination.

Among alkyl succinic acid having a branched alkyl group having 9 to 14 carbon atoms and / or alkenyl succinic acid having a branched alkenyl group having 9 to 14 carbon atoms, the affinity with the crystalline polyester is increased, and the fixing property of the toner is improved. From the viewpoint of enhancing, alkenyl succinic acid having a branched 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 fixing property of the toner, the number of carbon atoms of the branched alkyl group or branched alkenyl group is preferably 10 to 14, and more preferably 12 to 14.
Specific examples of the alkyl succinic acid having a branched alkyl group having 9 to 14 carbon atoms and / or the alkenyl succinic acid having a branched alkenyl group having 9 to 14 carbon atoms include dodecyl succinic acid, dodecenyl succinic acid, octenyl succinic acid, From the viewpoint of improving the fixing property of the toner, dodecenyl succinic acid is preferable.
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 increasing the compatibility with the amorphous polyester.
Alkyl succinic acid having a branched alkyl group having 9 to 14 carbon atoms and / or alkenyl succinic acid having a branched alkenyl group having 9 to 14 carbon atoms increases the affinity with the crystalline polyester, thereby improving the fixing property of the toner. From the viewpoint, it is preferably contained in the acid component in an amount of 30 to 60 mol%, more preferably 30 to 50 mol%, still more preferably 35 to 40 mol%.
As the aromatic dicarboxylic acid, terephthalic acid is preferable from the viewpoint of improving the chargeability of the toner.

Examples of the trivalent to pentavalent aromatic carboxylic acid include trimellitic acid, 2,5,7-naphthalenetricarboxylic acid, pyromellitic acid, and the like. Among them, the storage stability of the toner and charging in a high temperature and high humidity environment are exemplified. From the viewpoint of improving retention performance, trimellitic acid is preferred.
From the viewpoint of improving the storage stability of the toner and the charge retention performance in a high temperature and high humidity environment, the trivalent to pentavalent aromatic carboxylic acid is preferably contained in the acid component in an amount of 5 to 30 mol%, more preferably. Is contained in an amount of 7 to 20 mol%, more preferably 8 to 15 mol%, still more preferably 9 to 11 mol%.

  Preferred alcohol components include aromatic diols, and an alkylene (2 to 3 carbon) oxide adduct (average number of added moles of 1 to 16) of bisphenol A is preferred from the viewpoint of promoting non-crystallization.

The glass transition point of the amorphous polyester (b) is preferably 50 to 70 ° C, more preferably 53 to 65 ° C, more preferably 55 to 60 ° C, from the viewpoint of improving the durability, fixable region and storage stability of the toner. Is more preferable.
The softening point of the amorphous polyester (b) 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 fixable region and storage stability of the toner. 100-130 degreeC is especially preferable.
In addition, when using 2 or more types of amorphous polyesters (b) mixed, the glass transition point and the softening point are each described in the examples as a mixture of 2 or more types of amorphous polyesters (b). The value obtained by the method.

The number average molecular weight of the amorphous polyester (b) is preferably from 1,000 to 50,000, more preferably from 1,500 to 10,000, from the viewpoint of improving the durability, low-temperature fixability and storage stability of the toner. Preferably, 2,000 to 8,000 are more preferable, and 2,000 to 4,000 are more preferable.
The acid value of the amorphous polyester (b) is preferably 6 to 35 mgKOH / g, more preferably 10 to 35 mgKOH / g, and still more preferably 15 to 35 mgKOH / g, from the viewpoint of easily emulsifying the resin in an aqueous medium. .
Amorphous polyester (b) may be used alone or in combination of two or more.

[Colorant]
The toner core of the present invention preferably contains a colorant, and more preferably contains only a colorant. The content of the colorant is preferably 1 to 20 parts by weight with respect to 100 parts by weight of the resin constituting the toner core, from the viewpoint of improving the image density of the printed matter obtained using the toner, and 5 to 10 parts by weight. Is more preferable.

Examples of the colorant used in the present invention include pigments and dyes, and pigments are preferable from the viewpoint of improving the image density of the obtained printed matter.
Examples of the pigment include a cyan pigment, a yellow pigment, a magenta pigment, and a black pigment.
The cyan pigment is preferably a phthalocyanine pigment, and more preferably copper phthalocyanine. The yellow pigment is preferably a monoazo pigment, isoindoline pigment or benzimidazolone pigment, and the magenta pigment is preferably a soluble azo pigment such as quinacridone pigment or BONA lake pigment, or an insoluble azo pigment such as naphthol AS pigment. The black pigment is preferably carbon black.
Examples of the dye include an acridine dye, an azo dye, a benzoquinone dye, an azine dye, an anthraquinone dye, an indigo dye, a phthalocyanine dye, and an aniline black dye.
A coloring agent can be used individually by 1 type or in combination of 2 or more types.

〔Release agent〕
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 can be used alone or in combination of two or more, and it is preferable to use 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 75 to 90 ° C., and more preferably 80 to 90 ° C. from the viewpoint of the toner fixable region and storage stability. Further preferred. When using 2 or more types together, it is preferable that melting | fusing point of all is 60-90 degreeC from a viewpoint of 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 weight 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 usually preferably 1 to 20 parts by weight and preferably 2 to 15 parts by weight with respect to 100 parts by weight of the resin in the toner from the viewpoint of improving the releasability of the toner and improving the fixable region. Part is more preferred.

[Shell and graft polymer constituting the shell]
In the core-shell toner of the present invention, the shell is made of a graft polymer composed of a main chain segment (A1) made of a polyester resin and a side chain segment (A2) made of an addition polymerization resin.

(Main chain segment (A1) made of polyester resin)
The segment (A1) constituting the graft polymer is a main chain in the graft polymer, a segment made of a polyester resin, and a segment made of a polyester resin obtained by condensation polymerization of an alcohol component and a carboxylic acid component. . The raw material monomer from which the structural unit of segment (A1) is derived (hereinafter also simply referred to as “raw material monomer of segment (A1)”) is an alcohol component and a carboxylic acid component.

  As an alcohol component which is a raw material monomer of the segment (A1), 2,2-bis (4-hydroxy) is used from the viewpoint of improving a toner fixable region, storage stability, and charge holding performance in a high temperature and high humidity environment. It is preferred to use an alkylene oxide adduct of phenyl) propane.

Specifically, the alkylene oxide adduct of 2,2-bis (4-hydroxyphenyl) propane is preferably a compound represented by the following general formula (I).

In the general formula (I), R ¹ O and R ² O are both oxyalkylene groups, preferably each independently an oxyalkylene group having 1 to 4 carbon atoms, more preferably an oxyethylene group or an oxypropylene group. It is.
x and y correspond to the added mole number of alkylene oxide, and are positive numbers. Furthermore, from the viewpoint of increasing the reactivity with the carboxylic acid component, the average value of the sum of x and y is preferably 2 to 7, more preferably 2 to 5, and still more preferably 2 to 3.
Further, x R ¹ O or y R ² O may be the same or different from each other, but may be the same from the viewpoint of improving the low-temperature fixability and heat-resistant storage stability of the toner. Preferably, it is an oxypropylene group. The alkylene oxide adduct of 2,2-bis (4-hydroxyphenyl) propane may be used alone or in combination of two or more.

  From the viewpoint of improving the storage stability of the toner, the content of the oxypropylene group is preferably 50 to 100 mol%, more preferably 60 to 100 mol%, more preferably 70 to 100 mol in the oxyalkylene group. %, More preferably substantially 100 mol%. The other oxyalkylene group is preferably an oxyethylene group or an oxytrimethylene group, and more preferably an oxyethylene group, from the viewpoint of improving the toner fixable region and storage stability.

The alkylene oxide adduct of 2,2-bis (4-hydroxyphenyl) propane is preferably contained in the alcohol component in an amount of 60 mol% or more, more preferably from the viewpoint of improving the toner fixable area and storage stability. It is contained in an amount of 70 mol% or more, more preferably 80 mol% or more, and still more preferably 100 mol%. In the present invention, the alkylene oxide adduct means the whole structure in which an oxyalkylene group is added to 2,2-bis (4-hydroxyphenyl) propane.
Further, the propylene oxide adduct of 2,2-bis (4-hydroxyphenyl) propane is preferably contained in the alcohol component in an amount of 40 to 100 mol% from the viewpoint of improving the fixable region and storage stability of the toner. More preferably, it is 60-100 mol%, More preferably, 80-100 mol% is contained.

  Other alcohol components include, for example, ethylene glycol, propylene glycol (1,2-propanediol), glycerin, pentaerythritol, trimethylolpropane, hydrogenated bisphenol A, sorbitol, allyl alcohol or alkylene thereof (2 to 2 carbon atoms). 4) Oxide adduct (average number of added moles of 1 to 16) and the like. You may use the said alcohol component individually or in combination of 2 or more types.

  The carboxylic acid component which is a raw material monomer of the segment (A1) includes a dicarboxylic acid having a non-aromatic carbon-carbon unsaturated bond and having a carboxy group at both ends thereof, such as an unsaturated aliphatic dicarboxylic acid and / or Contains unsaturated alicyclic dicarboxylic acids. The carbon-carbon unsaturated bond portion is preferably a bond portion with the segment (A2) in the graft polymer. In this case, the unsaturated bond is a saturated bond. By using a dicarboxylic acid having a non-aromatic carbon-carbon unsaturated bond and having carboxy groups at both ends thereof, a carbon-carbon unsaturated bond can be introduced into the main chain of the resulting polyester.

  Examples of dicarboxylic acids (unsaturated aliphatic dicarboxylic acids and unsaturated alicyclic dicarboxylic acids) having a non-aromatic carbon-carbon unsaturated bond and having a carboxy group at both ends include fumaric acid and maleic acid. Unsaturated aliphatic dicarboxylic acid; unsaturated alicyclic dicarboxylic acid such as tetrahydrophthalic acid. From the viewpoint of reactivity, fumaric acid, maleic acid and tetrahydrophthalic acid are preferable, and fumaric acid is more preferable.

  The content of the dicarboxylic acid having a non-aromatic carbon-carbon unsaturated bond in the carboxylic acid component and having a carboxy group at both ends thereof is determined in terms of the fixable area of the toner, the storage stability, and the high temperature and high humidity environment. From the standpoint of improving the charge retention performance of the resin, it is more than 0 mol% and less than 20 mol%, preferably 0.5 to 15 mol%, more preferably 1 to 5 mol%, still more preferably 1 to 3 mol. %.

Other carboxylic acids include aromatic dicarboxylic acids, aliphatic dicarboxylic acids, alicyclic dicarboxylic acids, trivalent or higher polyvalent carboxylic acids, and anhydrides of these acids and their alkyls (1 to 3 carbon atoms). Examples include esters.
Among these, aromatic dicarboxylic acids and trivalent or higher polyvalent carboxylic acids are preferable from the viewpoint of improving the storage stability of the toner and the charge retention performance in a high-temperature and high-humidity environment. More preferred.
Examples of the aromatic dicarboxylic acid include phthalic acid, isophthalic acid, terephthalic acid and the like. From the above viewpoint, terephthalic acid is preferable.
Examples of the aliphatic dicarboxylic acid include adipic acid, succinic acid, succinic acid having an alkyl group and / or an alkenyl group.
Examples of the alicyclic dicarboxylic acids include cyclohexane dicarboxylic acids and decalin dicarboxylic acids.
Examples of the trivalent or higher polyvalent carboxylic acid include trimellitic acid and pyromellitic acid. From the above viewpoint, trimellitic acid is preferable.
The said carboxylic acid component may be individual or 2 or more types may be contained.

From the viewpoint of improving the dispersion stability of the resin particles, improving the storage stability of the toner, and improving the charge retention performance in a high-temperature and high-humidity environment, the acid value of the segment (A1) is preferably 5 to 40 mgKOH / g. Is 5 to 35 mgKOH / g, more preferably 10 to 30 mgKOH / g, still more preferably 15 to 25 mgKOH / g.
Further, from the viewpoint of improving the toner fixable region and storage stability, the number average molecular weight of the segment (A1) is preferably 1,000 to 10,000, more preferably 1,500 to 5,000.
In the present invention, as the acid group contained in the segment (A1), the carboxy group is preferably 90 mol% or more, and preferably substantially 100 mol% of the acid group.

(Side chain segment (A2) made of addition polymerization resin)
The segment (A2) constituting the graft polymer is a segment made of an addition polymerization resin composed of a structural unit derived from an addition polymerizable monomer (c2) (hereinafter also referred to as “monomer (c2)”). The segment (A2) is a side chain in the graft polymer.
Examples of the addition polymerizable monomer (c2) that can be used in the present invention include styrene, methylstyrene, α-methylstyrene, β-methylstyrene, t-butylstyrene, chlorostyrene, chloromethylstyrene, methoxystyrene, styrenesulfonic acid, Styrenes such as salts thereof; (meth) acrylic acid esters such as alkyl (meth) acrylate (1 to 18 carbon atoms), benzyl (meth) acrylate, dimethylaminoethyl (meth) acrylate; ethylene, propylene, butadiene Olefins such as vinyl chloride; vinyl esters such as vinyl acetate and vinyl propionate; vinyl ethers such as vinyl methyl ether; vinylidene halides such as vinylidene chloride; N-vinyl compounds such as N-vinylpyrrolidone; Etc.
Among these, styrenes and (meth) acrylic acid esters are preferable, among which addition polymerizable monomers having an aromatic group are more preferable, and styrene, methylstyrene, benzyl methacrylate and benzyl acrylate are more preferable. Among these, styrene is particularly preferable from the viewpoint of the raw material price of the monomer, the storage stability of the toner, and the charge retention performance in a high temperature and high humidity environment.
The content of the structural unit derived from the addition polymerizable monomer having an aromatic group is preferably in the segment (A2) from the viewpoint of improving the storage stability of the toner and the charge retention performance in a high temperature and high humidity environment. Is 85% by weight or more, more preferably 90% by weight or more, still more preferably 95% by weight or more, and further preferably substantially 100% by weight.

The weight ratio of the main chain segment (A1) and side chain segment (A2) constituting the graft polymer [main chain segment (A1) / side chain segment (A2)] is the toner fixable area, storage stability, And from the viewpoint of improving the charge retention performance in a high temperature and high humidity environment, it is 60/40 to 95/5, preferably 60/40 to 90/10, more preferably 65/35 to 83/17, still more preferably. Is 65/35 to 75/25.
By having the main chain segment (A1) and the side chain segment (A2) in this ratio, a relatively thick layer of the addition polymerization resin is formed on the outermost layer while maintaining the adhesion to the core. Therefore, it is considered that the fixable area of the toner, the storage stability, and the charge holding performance in a high temperature and high humidity environment can be improved.
Further, from the viewpoint of improving the storage stability of the toner and the charge retention performance in a high temperature and high humidity environment, the softening point of the graft polymer is preferably 110 to 170 ° C, more preferably 120 to 140 ° C.

[Method for producing toner for developing electrostatic image]
The method for producing a toner for developing an electrostatic charge image of the present invention preferably includes the following steps (1) to (3).
Step (1): The resin particles (A) containing the crystalline polyester (a) and the amorphous polyester (b) and the release agent particles containing the release agent are aggregated to obtain aggregated particles (1). Step Step (2): A resin particle (C) made of a graft polymer composed of a main chain segment (A1) made of a polyester resin and a side chain segment (A2) made of an addition polymerization type resin is added to form aggregated particles ( Step 2) Step (3): Fusing the agglomerated particles (2) to obtain core-shell particles

<Step (1)>
In the step (1), the resin particles (A) containing the crystalline polyester (a) and the amorphous polyester (b) and the release agent particles containing the release agent are aggregated to obtain the aggregated particles (1). Step of obtaining In this step, first, the resin particles (A) and the release agent particles are mixed in an aqueous medium to obtain a mixed dispersion.
In addition, although it is preferable to mix a colorant as an arbitrary component, the colorant may be mixed as a separate particle by itself, or may be contained in the resin particles (A). Therefore, it is preferably contained in the resin particles (A).
There is no restriction | limiting in order of mixing, You may add any in order and may add simultaneously.

(Resin particles (A))
The resin particles (A) contain a crystalline polyester (a) and an amorphous polyester (b) from the viewpoint of widening the fixable region of the toner.

The crystalline polyester (a) contained in the resin particles (A) is the same as the crystalline polyester (a) contained in the toner core, and preferred physical properties and composition are also the same.
The amorphous polyester (b) contained in the resin particles (A) is also the same as the amorphous polyester (b) contained in the toner core, and preferred physical properties and compositions are also the same.
The total amount of the crystalline polyester (a) and the amorphous polyester (b) in the resin particles (A) is also the same as that of the toner core, and from the viewpoint of improving the toner fixable region, the resin particles (A) The resin is preferably 50 to 100% by weight, more preferably 80 to 100% by weight, still more preferably 90 to 100% by weight, and particularly preferably substantially 100% by weight. The weight ratio ((a) / (b)) between the crystalline polyester (a) and the amorphous polyester (b) in the resin particles (A) is the toner fixable area, storage stability, and high temperature and high humidity environment. From the viewpoint of improving the charge retention performance under the above, it is preferably 5/95 to 50/50, more preferably 5/95 to 30/70, still more preferably 10/90 to 25/75, 15/85 ~ 20/80 is even more preferred.

[Production of resin particles (A)]
A resin particle (A) is a dispersion containing resin particles (A) by dispersing the above-mentioned optional components such as a resin containing a crystalline polyester (a) and an amorphous polyester (b) and a colorant in an aqueous medium. It is preferable to manufacture by the method obtained as a liquid.
Examples of the method for obtaining a dispersion include a method in which a resin or the like is added to an aqueous medium and dispersed using a disperser, a phase inversion emulsification method in which an aqueous medium is gradually added to the resin and emulsified, and the like. From the viewpoint of improving the low-temperature fixability of the toner, the phase inversion emulsification method is preferable. Hereinafter, the phase inversion emulsification method will be described.

First, the above-mentioned optional components such as a resin containing crystalline polyester (a), a resin containing amorphous polyester (b), an aqueous alkaline solution, and a colorant are melted and mixed to obtain a resin mixture.
When the resin is composed of a plurality of resins, a mixture of these resins may be used in advance, but when the alkaline aqueous solution and optional components are added, they are added simultaneously and melted and mixed. May be obtained. For example, the crystalline polyester (a) and the amorphous polyester (b) may be mixed in advance, but the crystalline polyester (a), the amorphous polyester (b), the alkaline aqueous solution, and the above optional components It is preferable to melt and mix at the same time to obtain a resin mixture from the viewpoint of improving the low-temperature fixability of the toner.
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 weight% is preferable, as for the density | concentration of the alkali in aqueous alkali solution, 1-25 weight% is more preferable, and 1.5-20 weight% 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 weight 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.

Nonionic surfactants include polyoxyethylene alkyl aryl ethers, polyoxyethylene alkyl ethers, polyoxyethylene fatty acid esters, oxyethylene / oxypropylene block copolymers, etc., among others, from the viewpoint of emulsion stability of the resin, Polyoxyethylene alkyl ether is preferred.
Examples of the polyoxyethylene alkyl aryl ether include polyoxyethylene nonyl phenyl ether.
Examples of the polyoxyethylene alkyl ether include polyoxyethylene oleyl ether and polyoxyethylene lauryl ether.
Examples of the polyoxyethylene fatty acid ester include polyethylene glycol monolaurate, polyethylene glycol monostearate, polyethylene glycol monooleate and the like.
Examples of anionic surfactants include dodecyl benzene sulfonate, dodecyl sulfate, alkyl ether sulfate, and the like. From the viewpoint of improving the emulsion stability of the resin, dodecyl benzene sulfonate, alkyl ether sulfate. Is preferred.
As dodecylbenzenesulfonate, an alkali metal salt of dodecylbenzenesulfonate is preferable, and sodium dodecylbenzenesulfonate is more preferable. As dodecyl sulfate, an alkali metal salt of dodecyl sulfate is preferable, and sodium dodecyl sulfate is more preferable. As the alkyl ether sulfate, an alkali metal salt of alkyl ether sulfate is preferable, and sodium alkyl ether sulfate is more preferable.
Examples of the cationic surfactant include alkylbenzene dimethyl ammonium chloride, alkyl trimethyl ammonium chloride, dialkyl ammonium chloride and the like.
The content of the surfactant is preferably 20 parts by weight or less, more preferably 15 parts by weight or less, still more preferably 0.1 to 10 parts by weight, with respect to 100 parts by weight of the resin constituting the resin particles (A). 0.5-10 weight part is still more preferable.

As a method for obtaining a resin mixture, a resin containing a crystalline polyester (a), a resin containing an amorphous polyester (b), an aqueous alkaline solution, and the above-mentioned optional component, preferably a surfactant, are put in a container and a stirrer. A method in which the resin is melted and mixed uniformly while stirring 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 (b), and more preferably equal to or higher than the melting point of the crystalline polyester (a) from the viewpoint of obtaining homogeneous resin particles. .

Next, an aqueous medium is added to the resin mixture and phase inversion is performed to obtain a dispersion containing resin particles (A).
As the aqueous medium, those containing water as a main component are preferable. From the viewpoint of improving the emulsion stability of the resin, the content of water in the aqueous medium is preferably 80% by weight or more, more preferably 90% by weight or more, and 95 More preferably, it is more preferably at least 100% by weight. 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 not less than the glass transition point of the amorphous polyester (b), and more preferably not less than the melting point of the crystalline polyester (a) from the viewpoint of obtaining uniform resin particles.
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 weight / 100 parts by weight of the resin constituting the resin particles (A) until the phase inversion is completed. Preferably 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 amount of the aqueous medium used is preferably 100 to 2000 parts by weight, and 150 to 1500 parts by weight with respect to 100 parts by weight 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 weight. From the viewpoint of improving the stability of the resulting resin particle dispersion, the solid content is preferably 7 to 50% by weight, more preferably 10 to 40% by weight, still more preferably 20 to 40% by weight, and still more preferably. 25 to 35% by weight. 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 (μm) / volume average particle size (μm)] × 100

In addition, the resin particles (A) may be particles composed only of a resin, but from the viewpoint of sharpening the particle size distribution of the toner, as described above, the resin particles (A) are obtained from a mixed resin containing a colorant. Is preferable, that is, it preferably contains a colorant, and is preferably a colorant-containing resin particle containing a colorant.
When the resin particles (A) are colorant-containing resin particles, the content of the colorant is 100 parts by weight of the resin constituting the resin particles (A) from the viewpoint of improving the image density of the printed matter obtained using the toner. 1 to 20 parts by weight is preferable, and 5 to 10 parts by weight is more preferable.

From the viewpoint of improving the toner fixable area, storage stability, and charge retention performance in a high-temperature and high-humidity environment, the polyester resin contained in the resin particles (A) is preferably cross-linked, and a compound having an oxazoline group is used. More preferably, it is crosslinked.
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 weight of the resin in the resin dispersion from the viewpoint of enhancing the crosslinking reactivity with the resin and improving the productivity. 0.1 to 30 parts by weight, more preferably 0.5 to 20 parts by weight, still more preferably 1 to 10 parts by weight.

  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.

(Release agent particles)
The release agent particles preferably contain a surfactant from the viewpoint of aggregation. As the surfactant, sodium polycarboxylate is preferable. In the case of using the surfactant, the content is preferably 0.01 to 10 parts by weight with respect to 100 parts by weight of the mold release agent, from the viewpoint of aggregation properties and chargeability of the obtained toner, Part by weight is more preferred.
The release agent used for the release agent particles is the same as that used for the toner core, and the preferred release agent is also the same.
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.

[Manufacture of release agent particles]
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, and a 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.

In the step (1), the resin particles (A) in the mixed dispersion are preferably 10 to 40 parts by weight, and more preferably 20 to 30 parts by weight. The aqueous medium is preferably 60 to 90 parts by weight, more preferably 70 to 80 parts by weight.
The colorant is preferably 1 to 20 parts by weight, preferably 3 to 15 parts by weight with respect to 100 parts by weight 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 weight, more preferably 2 to 15 parts by weight with respect to 100 parts by weight of the total of the resin and the colorant. .
The mixing temperature is preferably 0 to 40 ° C. from the viewpoint of controlling aggregation and obtaining particles having a target particle size.

(Aggregation)
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 weight or less, more preferably 40 parts by weight or less, still more preferably from 100 parts by weight of the resin constituting the resin particles (A), from the viewpoint of improving the chargeability of the toner. Is 30 parts by weight or less. In addition, from the viewpoint of controlling the aggregation of the resin particles to obtain a target particle size, it is preferably 1 part by weight or more, more preferably 3 parts by weight or more, with respect to 100 parts by weight of the resin constituting the resin particles (A). More preferably, it is 5 parts by weight or more. In consideration of the above points, the amount of the monovalent salt used is preferably 1 to 50 parts by weight, more preferably 3 to 40 parts by weight with respect to 100 parts by weight of the resin constituting the resin particles (A). More preferably, it is 5-30 weight part.

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 the addition of the aggregating agent and maintain the temperature. 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)>
In the step (2), resin particles (C) composed of a graft polymer composed of a main chain segment (A1) composed of a polyester resin and a side chain segment (A2) composed of an addition polymerization resin are added, and aggregated particles ( This is a step of obtaining 2).
In this step, the dispersion of resin particles (C) made of the graft polymer is added to the dispersion of aggregated particles (1) obtained in step (1), and resin particles are further added to the aggregated particles (1). It is preferable to attach (C) to obtain aggregated particles (2).

[Production method of resin particles (C)]
As a method for producing the resin particles (C) comprising the graft polymer used in the present invention, a polyester resin (c1) having a non-aromatic carbon-carbon unsaturated bond by polycondensing an alcohol component and a carboxylic acid component. ) (Hereinafter also referred to as resin (c1)), and addition polymerization of addition polymerizable monomer (c2) in the presence of the polyester resin (c1) is preferred.

(Polyester resin (c1))
The resin (c1) is a polyester resin having a non-aromatic carbon-carbon unsaturated bond in the main chain, and is preferable for constituting the main chain segment (A1) made of the polyester resin. The “non-aromatic carbon-carbon unsaturated bond” is derived from one or more selected from the unsaturated aliphatic dicarboxylic acids and unsaturated alicyclic dicarboxylic acids described above.

The raw material component of the resin (c1) is the same as that of the segment (A1), and the preferred embodiment is also the same.
The resin (c1) is obtained by using an alcohol component that preferably contains 50 mol% or more of an alkylene oxide adduct of 2,2-bis (4-hydroxyphenyl) propane as a raw material component.
Here, the alkylene oxide adduct of 2,2-bis (4-hydroxyphenyl) propane is the same as the segment (A1), and the preferred structure and the preferred content are also the same.

As an alcohol component which is a raw material component of the resin (c1), an alcohol component other than this can be used together with an alkylene oxide adduct of 2,2-bis (4-hydroxyphenyl) propane.
Other alcohols are the same as those in the segment (A1). You may use alcohol individually or in combination of 2 or more types.

The resin (c1) has a non-aromatic carbon-carbon unsaturated bond, and has a non-aromatic carbon-carbon unsaturated bond as a carboxylic acid component as a raw material component of the polyester. A dicarboxylic acid having a carboxy group at both ends is used.
The dicarboxylic acid having a non-aromatic carbon-carbon unsaturated bond and having a carboxy group at both ends thereof is the same as in the case of the segment (A1), and the preferred structure and preferred content are also the same. And fumaric acid is more preferred.
The content of the dicarboxylic acid having a non-aromatic carbon-carbon unsaturated bond in the carboxylic acid component is a viewpoint that improves the fixable region of the toner, the storage stability, and the charge retention performance in a high-temperature and high-humidity environment. Therefore, it is more than 0 mol% and less than 20 mol%, preferably 0.5 to 15 mol%, more preferably 1 to 5 mol%, still more preferably 1 to 3 mol%.
The other carboxylic acid is the same as in the case of the segment (A1), and the preferred structure and the preferred content are the same. An aromatic dicarboxylic acid is preferred, and terephthalic acid is more preferred. Carboxylic acids may be used alone or in combination of two or more.

The polyester resin (c1) is produced, for example, by subjecting the alcohol component and the carboxylic acid component to condensation polymerization at a temperature of 180 to 250 ° C. using an esterification catalyst as necessary in an inert gas atmosphere. be able to.
From the viewpoint of improving the storage stability of the toner and the charge holding performance in a high-temperature and high-humidity environment, it is preferable to perform condensation polymerization using a catalyst. Examples of the catalyst include tin compounds and titanium compounds from the viewpoint of increasing the efficiency of the condensation polymerization reaction. Among these, a tin compound is preferable, and di (2-ethylhexanoic acid) tin and dibutyltin oxide are more preferable.
In the present invention, since a carboxylic acid having a non-aromatic carbon-carbon unsaturated bond is used, it is preferable to use a radical polymerization inhibitor. The radical polymerization inhibitor is preferably 4-t-butylcatechol.

From the viewpoint of improving the storage stability of the toner and the charge retention performance in a high-temperature and high-humidity environment, the softening point of the resin (c1) is preferably 80 to 165 ° C., and the glass transition temperature is preferably 50 to 85 ° C. It is. From the viewpoint of improving the dispersion stability of the resin particle dispersion, the storage stability of the toner, and the charge retention performance in a high-temperature and high-humidity environment, the acid value of the resin (c1) is preferably 5 to 40 mgKOH / g. Is 5 to 35 mgKOH / g, more preferably 10 to 30 mgKOH / g, still more preferably 15 to 25 mgKOH / g.
The glass transition temperature, softening point, and acid value can all be obtained by appropriately adjusting the type of monomer used, the blending ratio, the temperature of condensation polymerization, and the reaction time.
Further, from the viewpoint of improving the fixable region and storage stability of the toner, the number average molecular weight of the resin (c1) is preferably 1,000 to 10,000, more preferably 1,500 to 5,000.

(Addition polymerizable monomer (c2))
The addition polymerizable monomer (c2) used in the present invention is the same as that described as the raw material monomer for the segment (A2) comprising the above addition polymerization resin. As the addition polymerizable monomer, styrene, benzyl methacrylate, and benzyl acrylate are preferable. Among these, styrene is preferable from the viewpoint of improving the raw material price of the monomer, the storage stability of the toner, and the charge retention performance in a high temperature and high humidity environment.

(Production of resin particles (C))
As described above, the method for producing the resin particles (C) comprising the graft polymer used in the present invention has a non-aromatic carbon-carbon unsaturated bond by polycondensing an alcohol component and a carboxylic acid component. A method of preparing the polyester resin (c1) and subjecting the addition polymerizable monomer (c2) to addition polymerization in the presence of the polyester resin (c1) is preferable. Specific examples include a method in which the resin (c1) and the monomer (c2) are directly mixed and polymerized, and a method in which the resin (c1) and the monomer (c2) are dissolved in an organic solvent and polymerized. In particular, the graft polymer used in the present invention is prepared by preparing an amorphous polyester resin (c1) having a non-aromatic carbon-carbon unsaturated bond, mixing the polyester resin (c1) with an aqueous medium, A step of obtaining an aqueous dispersion of the polyester resin (c1), and an addition-polymerizable monomer (c2) is added to the aqueous dispersion and polymerized to obtain an aqueous dispersion of resin particles (C) comprising a graft polymer. It is preferable to obtain by the method including a process.

In this step, the polyester resin (c1) is mixed with an aqueous medium to obtain an aqueous dispersion of the polyester resin (c1).
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. Hereinafter, the phase inversion emulsification method will be described.

First, a resin containing a polyester resin (c1), an alkaline aqueous 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 weight% is preferable, as for the density | concentration of the alkali in aqueous alkali solution, 1-25 weight% is more preferable, and 1.5-20 weight% is still more preferable.

The type of the surfactant is as described in the above-mentioned “Production of the resin fine particles (A)”, and in particular, the weight 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 weight or less, more preferably 15 parts by weight or less, still more preferably 0.1 to 10 parts by weight, based on 100 parts by weight of the polyester resin (c1). 10 parts by weight is more preferable.
As a method for obtaining the resin mixture, a method in which the polyester resin (c1) and an aqueous alkaline solution, preferably a surfactant, are put in a container and the resin is melted and mixed uniformly while stirring with a stirrer 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 polyester resin (c1).

Next, an aqueous medium is added to the resin mixture and phase inversion is performed to obtain a dispersion containing resin particles (C).
The type and content of the aqueous medium are as described in the above-mentioned “Production of resin fine particles (A)”.

The temperature at which the aqueous medium is added is preferably at least the glass transition point of the polyester resin (c1) from the viewpoint of obtaining homogeneous resin particles.
The addition rate of the aqueous medium is 0.1 to 50 parts by weight / min with respect to 100 parts by weight of the polyester resin (c1) until the phase inversion is completed from the viewpoint of obtaining resin particles having a small particle size. Preferably, it is 0.1 to 30 parts by weight / minute, more preferably 0.5 to 10 parts by weight / minute, and further preferably 0.5 to 5 parts by weight / minute. There is no restriction | limiting in the addition rate of the aqueous medium after phase inversion.
The amount of the aqueous medium used is preferably from 100 to 2000 parts by weight, more preferably from 150 to 1500 parts by weight, based on 100 parts by weight of the polyester resin (c1), from the viewpoint of obtaining uniform aggregated particles in the subsequent aggregation step. More preferred is ~ 500 parts by weight. From the viewpoint of improving the stability of the resulting resin particle dispersion, the solid content is preferably 7 to 50% by weight, more preferably 10 to 40% by weight, still more preferably 20 to 40% by weight, and still more preferably. 25 to 35% by weight. 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 of the polyester resin (c1) 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.

Next, the addition polymerizable monomer (c2) is added to the obtained aqueous dispersion and polymerized to obtain an aqueous dispersion of resin particles (C) made of a graft polymer.
Addition polymerizable monomer (c2) is added to the aqueous dispersion of polyester resin (c1). The addition amount is a weight ratio of the polyester resin (c1) and the addition polymerizable monomer (c2) from the viewpoint of improving the toner fixable region, storage stability, and charge holding performance in a high temperature and high humidity environment [polyester. Resin (c1) / addition polymerizable monomer (c2)], preferably 60/40 to 95/5, more preferably 60/40 to 90/10, more preferably 65/35 to 83/17, and further Preferably it is 65 / 35-75 / 25.
Moreover, you may add water etc. further from the point of the efficiency of stirring.

Further, the addition polymerizable monomer (c2) is polymerized in the presence of the polyester resin (c1).
Arbitrary radical polymerization initiators, crosslinking agents and the like are added to the polymerization as necessary. As the radical polymerization initiator, a water-soluble radical polymerization initiator is preferably used, and a persulfate is more preferably used.
The polymerization reaction is advanced by heating the mixed solution containing the polyester resin (c1) and the addition polymerizable monomer (c2). The polymerization temperature depends on the type of polymerization initiator used, but for example, when sodium persulfate is used, it is preferably 60 to 100 ° C., more preferably 70 to 90, from the viewpoint of efficiently performing the polymerization reaction. ° C.

The glass transition temperature of the graft polymer in the aqueous dispersion of the resin particles (C) obtained as described above is from the viewpoint of improving the storage stability of the toner and the charge retention performance in a high temperature and high humidity environment. Preferably it is 40-80 degreeC, More preferably, it is 50-80 degreeC, More preferably, it is 60-70 degreeC. The softening point of the graft polymer is preferably 110 to 170 ° C., more preferably 120 to 140 ° C., from the viewpoint of improving the fixable region and storage stability of the toner.
The solid content concentration of the aqueous dispersion of the resin particles (C) is preferably 10 to 40% by weight, more preferably 15 to 35% by weight, and still more preferably from the viewpoint of improving the dispersibility of the resin particles and improving the productivity. Is 20-30% by weight. When used in step (2) of the present invention, it is preferably adjusted to the above concentration and used as an aqueous dispersion.
The pH of the aqueous dispersion of resin particles (C) at 25 ° C. is preferably 5 to 10, more preferably 5 to 8, from the viewpoint of improving the storage stability of the aqueous dispersion of resin particles (C). More preferably, it is 6-7.

The volume-median particle size (D ₅₀ ) of the resin particles in the aqueous dispersion of the resin particles (C) obtains a toner having a sharp particle size distribution, thereby improving the charge retention performance in a high-temperature and high-humidity environment. From the viewpoint, it is preferably 0.02 to 1.0 μm, more preferably 0.05 to 0.80 μm, still more preferably 0.08 to 0.50 μm.

In step (2), before adding the dispersion liquid (resin particle (C) dispersion) containing the resin particles (C) to the dispersion liquid (aggregation particles (1) dispersion) containing the aggregated particles (1). The aqueous dispersion may be diluted by adding an aqueous medium to the aggregated particle (1) dispersion, and it is preferable to add an aqueous medium. By adding an aqueous medium to obtain a predetermined coagulant concentration, the resin particles (C) can be more uniformly adhered to 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 the crystalline polyester (a) contained in the resin particles (A) from the viewpoint of improving the toner fixable region, storage stability, and charge retention performance in a high temperature and high humidity environment. The temperature is preferably 5 ° C. or more lower than the melting point, 3 ° C. higher than the glass transition point of the amorphous polyester (b), more preferably lower than the glass transition point, and 3 ° C. higher than the glass transition point of the resin particles (C). The following is preferable, and below the glass transition point is more preferable. When the aggregated particles (2) are produced in this temperature range, the fixable region of the obtained toner is expanded and the storage stability is improved. The reason for this is not clear, but because the agglomeration of the aggregated particles (2) does not occur, the generation of coarse particles is suppressed, and the crystallinity of the crystalline polyester (a) can be maintained. Conceivable.

The amount of the resin particles (C) added is determined between the resin particles (C) and the resin particles (A) from the viewpoint of improving the fixable area of the toner, storage stability, and charge holding performance in a high temperature and high humidity environment. The weight ratio (resin particles (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. An amount is preferred.
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 (a) and the amorphous polyester (b) are mixed is sufficiently obtained. In addition, the fixing property at high temperature can be improved, and the heat-resistant storage stability can also be improved.

  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 weight with respect to 100 parts by weight 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 weight part, More preferably, it is 0.1-8 weight part. 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)>
Step (3) is a step of fusing the agglomerated particles (2) obtained in step (2) to obtain core-shell particles, which are mainly physically attached to each other in the agglomerated particles (2). The particles that were in a state of being in a fused state are fused together to form core-shell particles.

From the viewpoint of promoting fusing and improving the productivity of the toner, in this step, the temperature is preferably 10 ° C. or more, more preferably the glass transition point or more, more preferably the glass transition point, more than the glass transition point of the graft polymer. Hold at a temperature of 5 ° C. or higher. From the viewpoint of improving the storage stability while maintaining the core-shell state of the toner and maintaining the fixable region, in this step, the temperature is preferably 30 ° C. or higher, more preferably 20 ° C. higher than the glass transition point of the graft polymer. The temperature is kept at a high temperature or lower, more preferably 15 ° C. or higher.
When the glass transition point of the graft polymer is Tg and the holding temperature is T, T ≧ Tg−10 ° C., more preferably T ≧ Tg, more preferably T ≧ Tg + 5 ° C., preferably T ≦ Tg + 30 ° C. More preferably, T ≦ Tg + 20 ° C., and further preferably T ≦ Tg + 15 ° C.
Further, from the viewpoint of improving the fixable region of the toner, in this step, the temperature is preferably maintained at a temperature not higher than 5 ° C., more preferably not higher than the melting point of the crystalline polyester (a).
Further, from the viewpoint of improving the fixable region of the toner, in this step, the temperature 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, and still more preferably, from the viewpoint of improving particle fusing property, storage stability, chargeability and toner productivity. Is 1-12 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.

<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 weight or less, more preferably 1.0% by weight or less, from the viewpoint of suppressing toner scattering and improving the chargeability.

[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 fixable region of the toner. The glass transition point is preferably 30 to 80 ° C., more preferably 40 to 70 ° C. from the viewpoint of improving the fixable region, storage stability, and charge retention performance in a high temperature and high humidity environment.
The toner of the present invention has a core-shell structure, and preferably 50 to 100% by weight, more preferably 70 to 100% by weight, and still more preferably 90 to 100% by weight of the total amount of the amorphous polyester (c1) in the shell part. %.
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 0.955 to 0.985, more preferably 0.958 to 0.980, and still more preferably 0.960 to 0.975, from the viewpoint of improving toner cleaning properties.
The BET specific surface area of the toner is preferably 1.2 to 2.5, more preferably 1.4 to 2.2, from the viewpoint of improving the storage stability of the toner and the charge holding performance in a high temperature and high humidity environment. 1.6 to 2.0 is more preferable.

(External additive)
In the 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 the toner particles is performed using the external additive, the amount of the external additive added is preferably 1 to 5 parts by weight, more preferably 100 parts by weight of the toner particles before the treatment with the external additive. 2 to 4 parts by weight.

  The electrostatic image developing toner 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.

  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.

[Polyester softening point, endothermic maximum peak temperature, melting point, glass transition point and 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) Endothermic maximum peak temperature, melting point and glass transition point The temperature was raised to 200 ° C. using a differential scanning calorimeter (manufactured by PerkinElmer, trade name: Pyris 6 DSC), and the temperature was lowered at a rate of 10 ° C./min. The sample cooled to 0 ° C. 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 Aggregated Particles]
The volume median particle size of the aggregated particles 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)
Measurement conditions: 30,000 particles are measured after adjusting the particle size of 30,000 particles to a concentration that can be measured in 20 seconds by adding a sample dispersion containing aggregated particles to 100 mL of the electrolyte. The volume-median particle size (D ₅₀ ) was determined.
The CV value (%) as the particle size distribution 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

[Volume Median Particle Size (D ₅₀ ), Volume Average Particle Size (D _v ), and Particle Size Distribution of Toner (Particles)]
The volume median particle size of the toner (particles) was measured as follows.
The measuring instrument, aperture diameter, analysis software, and electrolyte solution were the same as the volume median particle diameter of the aggregated particles.
-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 weight.
-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: After adjusting the particle size of 30,000 particles to a concentration that can be measured in 20 seconds by adding the sample dispersion to 100 mL of the electrolytic solution, 30,000 particles are measured, and the volume is medium. The particle size (D ₅₀ ) was determined.
The CV value (%) as the particle size distribution 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

[Volume Median Particle Size (D ₅₀ ) and Particle Size Distribution of Resin Particles, 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 where the absorbance was in the proper range. The CV value was calculated from the volume average particle size 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) × 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 Co., Ltd.), a measurement sample 5 g was dried at a temperature of 150 ° C. and a measurement mode 96 (monitoring time 2.5 minutes / variation width 0.05%). ) To measure the moisture percentage. The solid content concentration was calculated according to the following formula.
Solid content concentration (% by weight) = 100-M
M: moisture (%) = [(W−W ₀ ) / W] × 100
W: Sample weight before measurement (initial sample weight)
W ₀ : Sample weight after measurement (absolute dry weight)

[Toner circularity]
-Preparation of dispersion: The dispersion of core-shell particles was prepared by diluting with deionized water so that the solid content concentration of the core-shell particles was 0.001 to 0.05%. The toner dispersion was prepared by adding 50 mg of toner to 5 ml of 5% by weight polyoxyethylene lauryl ether (Emulgen 109P) aqueous solution, dispersing for 1 minute with an ultrasonic disperser, and then adding 20 ml of distilled water. It was prepared by dispersing for 1 minute with an ultrasonic disperser.
Measurement device: Flow-type particle image analyzer (manufactured by Sysmex Corporation, trade name: FPIA-3000)
・ Measurement mode: HPF measurement mode

[Evaluation of toner fixing temperature range]
(Minimum fixing temperature)
Using a commercially available printer (trade name: Microline 5400, manufactured by 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 without being fixed at a length of 50 mm, leaving a margin of 5 mm from the top edge of the A4 paper.
Next, the same printer with the temperature-variable fixing device prepared was prepared, the temperature of the fixing device was set to 90 ° C., and fixing was performed at a speed of 1.5 seconds per sheet in the A4 longitudinal direction, thereby obtaining a printed matter.
In the same manner, the temperature of the fixing device was increased by 5 ° C., and the fixing was performed to obtain a printed matter.
A mending tape (product name: Scotch Mending Tape 810, width 18 mm) is lightly pasted from the margin of the printed material to the image area, and then a 500 g weight is placed on it, making one round trip at a speed of 10 mm / sec. Pressed. Thereafter, the affixed tape was peeled off from the lower end side at a peeling angle of 180 degrees and a speed of 10 mm / second to obtain a printed matter after the tape was peeled off. 30 sheets of high quality paper (Oki Data Co., Ltd., Excellent White Paper A4 size) is placed under the printed material before and after the tape is applied, and the reflected image density of the fixed image portion before and after the tape is applied to each printed material. , Measured using a colorimeter (GretagMacbeth, trade name: SpectroEye, light emission condition: standard light source D ₅₀ , observation field of view 2 °, density standard DINNB, absolute white standard) Calculated.
Fixing rate = (reflected image density after peeling tape / reflected image density before applying tape) × 100
The temperature at which the fixing rate was 90% or more was defined as the minimum fixing temperature.

(Maximum fixing temperature)
Further, the temperature of the fixing device was increased by 5 ° C. in the same manner, and the above test was performed until the temperature at which hot offset occurred. Hot offset refers to a phenomenon in which toner adheres to the fixing roller when the temperature of the fixing device is high. In this test, it was determined that hot offset occurred when the toner adhering to the fixing roller adhered to the paper surface at a portion of 87 mm from the upper end of the solid image on the paper surface when the fixing roller made one round. The maximum fixing temperature at which no hot offset occurred was defined as the maximum fixing temperature.

(Fixable temperature range)
The difference between the maximum fixing temperature and the minimum fixing temperature was determined as the fixing possible temperature range. The wider the fixable temperature range, the more the fixing can be performed in any temperature range and the better the fixability.

[Evaluation of storage stability of toner]
20 g of toner was put in a wide-mouthed polybin having an internal volume of 100 ml, sealed, and allowed to stand at a temperature of 55 ° C. for 24 hours. Thereafter, it was allowed to stand for 12 hours or more while being sealed at a temperature of 25 ° C. and cooled. Next, a sieve having a mesh size of 250 μm is set on a powder tester (trade name, manufactured by Hosokawa Micron Co., Ltd.), and 20 g of the toner is placed on the shaker for 30 seconds. The remaining toner weight on the sieve is measured. It was measured. The smaller the value, the better the storage stability of the toner.

[Evaluation of toner chargeability]
Under an LL environment (10 ° C., 20% RH), 2.1 g of toner and 27.9 g of a silicone ferrite carrier (manufactured by Kanto Denka Kogyo Co., Ltd., average particle size: 40 μm) and a 50 cc cylindrical polypropylene bottle (manufactured by Nikko Corporation) ), And pre-stirred by shaking 10 times vertically and horizontally. Thereafter, the charge amount at a mixing time of 1 hour was measured using a tumbler mixer using a q / m meter (manufactured by EPPING) to obtain the charge amount in an LL environment.
Measuring instrument: q / m-meter manufactured by EPPING
Configuration:
Mesh size: 635 mesh (aperture: 24 μm, made of stainless steel)
Soft blow Blow pressure (600V)
Suction time: 90 seconds Charge amount (μC / g) = Total amount of electricity after 90 seconds (μC) / Amount of toner sucked (g)
After completion of the measurement, the developer is placed in an NN environment (25 ° C., 50% RH) and held for 12 hours. Thereafter, the developer taken out from the NN environment was stirred for 10 minutes with a tumbler mixer and then measured to obtain the charge amount in the NN environment.
The developer after measurement is placed in an HH environment (30 ° C., 85% RH) and held for 12 hours. Thereafter, the developer taken out from the HH environment was stirred for 10 minutes with a tumbler mixer and then measured to obtain the charge amount in the HH environment.
The smaller the difference between the charge amount in the LL environment and the charge amount in the HH environment, the better the charge retention performance in a high temperature and high humidity environment.

[Production of polyester]
Production Example 1
(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 di (2-ethylhexanoic acid) tin was added, and the mixture was further maintained at 200 ° C. for 1 hour. Then, the pressure in the flask was lowered and maintained at 8.3 kPa for 4 hours to obtain crystalline polyester X1. . The physical properties are shown in Table 1.

Production Example 2
(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 3528 g of polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, Put 1404 g of polyoxyethylene (2.0) -2,2-bis (4-hydroxyphenyl) propane, 1248 g of terephthalic acid, 1541 g of dodecenyl succinic anhydride, and 40 g of di (2-ethylhexanoic acid) tin under a nitrogen atmosphere. While stirring, the temperature was raised to 230 ° C. and maintained at 230 ° C. for 6 hours, and then the pressure in the flask was further lowered and maintained at 8.3 kPa for 1 hour. Then, after cooling to 215 ° C. and returning to atmospheric pressure, 300 g of trimellitic anhydride was added and maintained at 215 ° C. for 1 hour, then the pressure in the flask was further lowered and maintained at 8.3 kPa for 3 hours. As a result, amorphous polyester Y1 was obtained. The physical properties are shown in Table 1.

Production Example 3
(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, Polyoxyethylene (2.0) -2,2-bis (4-hydroxyphenyl) propane 1625 g, terephthalic acid 1145 g, dodecenyl succinic anhydride 161 g, and di (2-ethylhexanoic acid) 25 g were put under a nitrogen atmosphere. While stirring, the temperature was raised to 230 ° C. and maintained at 230 ° C. for 5 hours, and then the pressure in the flask was further lowered and maintained at 8.0 kPa for 1 hour. After returning to atmospheric pressure, it was cooled to 220 ° C. and 480 g of trimellitic anhydride was added. Then, after confirming that the softening point measured according to ASTM D36-86 reached 120 ° C., the reaction was stopped by lowering the temperature to obtain amorphous polyester Y2. The physical properties are shown in Table 1.

Production Example 4
(Production of amorphous polyester Y3)
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 5670 g of polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, 585 g of polyoxyethylene (2.0) -2,2-bis (4-hydroxyphenyl) propane, 2450 g of terephthalic acid, and 44 g of di (2-ethylhexanoic acid) are added to 235 ° C. with stirring in a nitrogen atmosphere. The temperature was raised and maintained for 5 hours, and then the pressure in the flask was further lowered and maintained at 8.0 kPa for 1 hour. After returning to atmospheric pressure, the mixture was cooled to 190 ° C., added with 42 g of fumaric acid and 207 g of trimellitic acid, maintained at 190 ° C. for 2 hours, and then heated to 210 ° C. over 2 hours. Further, the pressure in the flask was lowered and maintained at 8.0 kPa for 4 hours to obtain amorphous polyester Y3. The physical properties are shown in Table 1.

Production Example 5
(Production of amorphous polyester Y4)
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 5670 g of polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, 585 g of polyoxyethylene (2.0) -2,2-bis (4-hydroxyphenyl) propane, 2390 g of terephthalic acid, and 45 g of di (2-ethylhexanoic acid) are added to 235 ° C. with stirring in a nitrogen atmosphere. The temperature was raised and maintained for 5 hours, and then the pressure in the flask was further lowered and maintained at 8.0 kPa for 1 hour. After returning to atmospheric pressure, the mixture was cooled to 180 ° C., 104 g of fumaric acid and 207 g of trimellitic acid were added, maintained at a temperature of 180 ° C. for 2 hours, and then heated to 195 ° C. over 2 hours. Further, the pressure in the flask was lowered and maintained at 8.0 kPa for 4 hours to obtain amorphous polyester Y4. The physical properties are shown in Table 1.

Production Example 6
(Production of amorphous polyester Y5)
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 3487 g of polyoxyethylene (2.0) -2,2-bis (4-hydroxyphenyl) propane, 1247 g of terephthalic acid and 25 g of di (2-ethylhexanoic acid) were added, the temperature was raised to 230 ° C. with stirring in a nitrogen atmosphere and maintained for 5 hours, and then the pressure in the flask was further lowered at 8.0 kPa. Maintained for 1 hour. After returning to atmospheric pressure, the mixture was cooled to 190 ° C., 411 g of fumaric acid and 2.5 g of tert-butylcatechol (polymerization inhibitor) were added, maintained at 190 ° C. for 1 hour, and then 210 ° C. over 2 hours. The temperature was raised to. Further, the pressure in the flask was lowered and maintained at 8.0 kPa for 4 hours to obtain amorphous polyester Y5. The physical properties are shown in Table 1.

[Production of resin particles]
Production Example 7
(Production of resin particle dispersion A-1)
In a flask equipped with a stirrer, 90 g of crystalline polyester X1, 510 g of amorphous polyester Y1, copper phthalocyanine pigment (trade name: ECB301, manufactured by Dainichi Seika Kogyo Co., Ltd.), polyoxyethylene alkyl ether (nonionic) Surfactant, trade name: Emulgen 150, manufactured by Kao Corporation) 8.5 g, 15 wt% sodium dodecylbenzenesulfonate aqueous solution (anionic surfactant, trade name: Neoperex G-15, manufactured by Kao Corporation) ) 80 g, 225 g of a 5 wt% potassium hydroxide aqueous solution was added, and the mixture was heated to 98 ° C. with melting and melted, and mixed at 98 ° C. for 2 hours to obtain a resin mixture.
Next, 1118 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., and stirred at 25 ° C., while stirring the oxazoline group-containing polymer aqueous solution (trade name: Epocross WS-700, manufactured by Nippon Shokubai Co., Ltd., nonvolatile content 25% by weight, acrylic 28 g of the main chain) was added, and then the temperature was raised to 95 ° C. and held at 95 ° C. for 1 hour. Next, the mixture was cooled to 25 ° C., and the obtained emulsion was passed through a 200 mesh (mesh opening 105 μm) wire mesh to obtain a resin particle dispersion A-1. The physical properties are shown in Table 2.

Production Example 8
(Production of resin particle dispersion B-1)
In a reaction vessel with an internal volume of 5 liters, in a flask, amorphous polyester Y3 600 g, polyoxyethylene alkyl ether (nonionic surfactant, trade name: Emulgen 430, manufactured by Kao Corporation) 6 g, 15 wt% dodecyl Sodium benzenesulfonate aqueous solution (anionic surfactant, trade name: Neoperex G-15, manufactured by Kao Corporation) 40 g and 5 wt% potassium hydroxide 233 g were added, and the temperature was raised to 95 ° C. while stirring. The mixture was melted and mixed at 95 ° C. for 2 hours to obtain a resin mixture.
Next, 1145 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, the solid content was adjusted to 28.0 wt%, and resin particle dispersion B-1 was obtained. Obtained. The physical properties are shown in Table 2.

Production Example 9
(Production of resin particle dispersion B-2)
A resin particle dispersion B-2 was obtained in the same manner as in Production Example 8 except that the amorphous polyester Y3 was changed to the amorphous polyester Y4 in Production Example 8. The physical properties are shown in Table 2.

Production Example 10
(Production of resin particle dispersion B-3)
In a reaction vessel having an internal volume of 5 liters, 186 g of amorphous polyester Y5, 414 g of amorphous polyester Y2 and polyoxyethylene alkyl ether (nonionic surfactant, trade name: Emulgen 430, manufactured by Kao Corporation) ) 6 g, 15 wt% sodium dodecylbenzenesulfonate aqueous solution (anionic surfactant, trade name: Neoperex G-15, manufactured by Kao Corp.) 40 g and 5 wt% potassium hydroxide 239 g, while stirring, The mixture was heated to 95 ° C. and melted, and mixed at 95 ° C. for 2 hours to obtain a resin mixture.
Next, 1139 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 28.0% by weight, and a resin particle dispersion B-3 was obtained. Obtained. The physical properties are shown in Table 2.

Production Example 11
(Production of resin particle dispersion B-4)
In a reaction vessel having an internal volume of 5 liters, 312 g of amorphous polyester Y5, 288 g of amorphous polyester Y2 and polyoxyethylene alkyl ether (nonionic surfactant, trade name: Emulgen 430, manufactured by Kao Corporation) ) 6 g, 15 wt% sodium dodecylbenzenesulfonate aqueous solution (anionic surfactant, trade name: Neoperex G-15, manufactured by Kao Corp.) 40 g and 231 g of 5 wt% potassium hydroxide 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, 1146 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 28.0% by weight, and resin particle dispersion B-4 was prepared. Obtained. The physical properties are shown in Table 2.

Production Example 12
(Production of resin particle dispersion B-5)
In a reaction vessel with an internal volume of 5 liters, 390 g of amorphous polyester Y5, 210 g of amorphous polyester Y2, polyoxyethylene alkyl ether (nonionic surfactant, trade name: Emulgen 430, manufactured by Kao Corporation) ) 6 g, 15 wt% sodium dodecylbenzenesulfonate aqueous solution (anionic surfactant, trade name: Neoperex G-15, manufactured by Kao Corporation) 40 g and 5 wt% potassium hydroxide 225 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, 1151 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 28.0% by weight, and resin particle dispersion B-5 was prepared. Obtained. The physical properties are shown in Table 2.

Production Example 13
(Production of resin particle dispersion B-6)
In a reaction vessel having an internal volume of 5 liters, 456 g of amorphous polyester Y5, 144 g of amorphous polyester Y2 and polyoxyethylene alkyl ether (nonionic surfactant, trade name: Emulgen 430, manufactured by Kao Corporation) ) 6 g, 15 wt% sodium dodecylbenzenesulfonate aqueous solution (anionic surfactant, trade name: Neoperex G-15, manufactured by Kao Corporation) 40 g, 5 wt% potassium hydroxide 221 g and deionized water 50 g While stirring, the mixture was heated to 95 ° C. and melted, and mixed at 95 ° C. for 2 hours to obtain a resin mixture.
Next, 1106 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 28.0% by weight, and resin particle dispersion B-6 was prepared. Obtained. The physical properties are shown in Table 2.

Production Example 14
(Production of resin particle dispersion C-1)
857 g of resin particle dispersion B-1 was added to a 2-liter four-necked flask equipped with a condenser, a stirrer, and a thermocouple, and stirred under a nitrogen atmosphere at 25 ° C. with a stirring speed of 200 r / min. It was. Thereafter, 60 g of styrene was added and further mixed for 30 minutes. Next, the temperature was raised to 80 ° C. with stirring for 1 hour, and 23.3 g of a 1% by weight sodium persulfate aqueous solution was added as an initiator to perform polymerization for 3 hours. Thereafter, 23.3 g of a 1% by weight aqueous sodium persulfate solution was further added, mixed for 3 hours, cooled to 25 ° C., passed through a 200-mesh wire mesh, deionized water was added, and the solid content was reduced to 23.5% by weight. The resin particle dispersion C-1 was obtained by adjusting. Table 3 shows the physical properties.

Production Example 15
(Production of resin particle dispersion C-2)
Production Example 14 Production Example 14 except that 857 g of resin particle dispersion B-1 was changed to 750 g, 60 g of styrene was changed to 90 g, and 23.3 g of a 1 wt% aqueous sodium persulfate solution added twice was changed to 35.0 g. In the same manner as in Example 14, a resin particle dispersion C-2 was obtained. Table 3 shows the physical properties.

Production Example 16
(Production of resin particle dispersion C-3)
Production Example 14 Production Example 14 except that 857 g of resin particle dispersion B-1 was changed to 911 g, 60 g of styrene was changed to 45 g, and 23.3 g of a 1 wt% aqueous sodium persulfate solution added twice was changed to 17.5 g. In the same manner as in Example 14, a resin particle dispersion C-3 was obtained. Table 3 shows the physical properties.

Production Example 17
(Production of resin particle dispersion C-4)
In Production Example 14, 857 g of resin particle dispersion B-1 was added to 1018 g of resin particle dispersion B-2, 15 g of styrene was added to 15 g, and 23.3 g of a 1 wt% aqueous sodium persulfate solution added twice was added to 5.8 g. Except having changed, it carried out similarly to manufacture example 14, and obtained resin particle dispersion C-4. Table 3 shows the physical properties.

Production Example 18
(Production of resin particle dispersion C-5)
A resin particle dispersion C-5 was obtained in the same manner as in Production Example 17, except that the resin particle dispersion B-2 was changed to the resin particle dispersion B-3 in Production Example 17. Table 3 shows the physical properties.

Production Example 19
(Production of resin particle dispersion C-6)
A resin particle dispersion C-6 was obtained in the same manner as in Production Example 17, except that the resin particle dispersion B-2 was changed to the resin particle dispersion B-4 in Production Example 17. Table 3 shows the physical properties.

Production Example 20
(Production of resin particle dispersion C-7)
In Production Example 14, 857 g of resin particle dispersion B-1 was changed to 1050 g, 60 g of styrene was changed to 6 g, and 23.3 g of 1 wt% aqueous sodium persulfate solution added twice was changed to 2.3 g, respectively. Except that, in the same manner as in Production Example 14, a resin particle dispersion C-7 was obtained. Table 3 shows the physical properties.

Production Example 21
(Production of resin particle dispersion C-8)
536 g of resin particle dispersion B-1 and 314 g of deionized water were added to a 2-liter four-necked flask equipped with a condenser, a stirrer, and a thermocouple, and stirred at 200 ° C./min at 25 ° C. in a nitrogen atmosphere. The mixture was stirred and mixed. Thereafter, 150 g of styrene was added and further mixed for 30 minutes. Next, the temperature was raised to 80 ° C. with stirring for 1 hour, and 5.83 g of a 10 wt% sodium persulfate aqueous solution was added as an initiator to perform polymerization for 3 hours. Thereafter, 5.83 g of a 10 wt% sodium persulfate aqueous solution was further added and mixed for 3 hours, then cooled to 25 ° C., passed through a 200 mesh wire net, deionized water was added, and the solid content was reduced to 23.5 wt%. Adjustment was performed to obtain a resin particle dispersion C-8. Table 3 shows the physical properties.

Production Example 22
(Production of resin particle dispersion C-9)
A resin particle dispersion C-9 was obtained in the same manner as in Production Example 14, except that the resin particle dispersion B-1 was changed to the resin particle dispersion B-5 in Production Example 14. Table 3 shows the physical properties.

Production Example 23
(Production of resin particle dispersion C-10)
In Production Example 14, 857 g of resin particle dispersion B-1 was added to 1018 g of resin particle dispersion B-6, 15 g of styrene was added to 15 g, and 23.3 g of 1 wt% aqueous sodium persulfate solution added twice was added to 5.8 g. Except having changed, it carried out similarly to manufacture example 14, and obtained resin particle dispersion liquid C-10. Table 3 shows the physical properties.

[Manufacture of release agent particles]
Production Example 24
(Production of release agent particle dispersion)
2. In a 1 liter beaker, sodium acrylate-sodium maleate copolymer aqueous solution (trade name: Poise 521, effective concentration 40% by weight, manufactured by Kao Corporation) as a sodium polycarboxylate aqueous solution in 200 g of deionized water 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) were dissolved therein. −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 (trade name: US-600T, manufactured by Nippon Seiki Seisakusho Co., Ltd.) while maintaining the temperature at 90 to 95 ° C. After cooling to room temperature, ion exchange water was added thereto to adjust the release agent solid content to 20% by weight to obtain a release agent particle dispersion. The volume median particle size (D ₅₀ ) of the release agent particles in the release agent particle dispersion was 0.45 μm, and the CV value was 30%.

[Production of toner]
Example 1
(Preparation of Toner 1)
In a three-liter four-necked flask equipped with a dehydration tube, a stirrer, and a thermocouple, 250 g of resin particle dispersion A-1, 71 g of deionized water, and 19 g of release agent particle dispersion were added at a temperature of 25 ° C. Mixed. Next, while stirring the mixture, an aqueous solution in which 21 g of ammonium sulfate was dissolved in 175 g of deionized water was added dropwise at 25 ° C. over 5 minutes, and then the temperature was raised to 64 ° C. The dispersion liquid (1) containing aggregated particles was obtained by maintaining at 64 ° C. until it became 0.8 μm.
66 g of deionized water was added to the aggregated particle dispersion (1) (total amount), and the temperature of the dispersion was cooled to 54 ° C. Next, while increasing the temperature of the dispersion at 54 ° C. at a rate of 1.0 ° C. per hour, 96 g of the resin particle dispersion C-1 was dropped at a rate of 0.4 ml per minute to obtain an aggregated particle dispersion (2). It was. Table 4 shows the physical properties of the aggregated particle dispersion (2). Moreover, the temperature of the dispersion liquid after completion | finish of dripping was 58 degreeC.
An aqueous solution obtained by mixing 15 g of an anionic surfactant (trade name: EMAL (registered trademark) E27C, effective concentration: 27% by weight), and 1350 g of deionized water was added to the aggregated particle dispersion (2). The temperature was raised to 72 ° C. and held at 72 ° C. for 4 hours to fuse the particles to obtain core-shell particles.
The obtained core-shell particle dispersion was cooled to 25 ° C., the solid content of the dispersion was separated by suction filtration, washed with deionized water, and dried at 33 ° C. to obtain toner particles. 100 parts by weight of the toner particles, 2.5 parts by weight of hydrophobic silica (manufactured by Nippon Aerosil Co., Ltd., trade name: RY50, average particle size; 0.04 μm), and hydrophobic silica (manufactured by Cabot Corporation, trade name: Cabo Seal TS720) , Average particle diameter: 0.012 μm) 1.0 part by weight was put in a Henschel mixer, stirred, and passed through a 150-mesh sieve to obtain toner 1. Table 4 shows the physical properties and evaluation of the toner.

Examples 2-6
(Production of toners 2 to 6)
Toners 2 to 6 were obtained in the same manner as in Example 1 except that the resin particle dispersion C-1 in Example 1 was changed to the resin particle dispersion shown in Table 4. Table 4 shows the physical properties and evaluation of the toner.

Comparative Example 1
(Preparation of Toner 7)
A toner 7 was obtained in the same manner as in Example 1 except that 96 g of the resin particle dispersion C-1 was changed to a dispersion obtained by mixing 81 g of the resin particle dispersion B-1 and 16 g of deionized water. . Table 4 shows the physical properties and evaluation of the toner.

Comparative Examples 2-5
(Production of toners 8 to 11)
Toners 8 to 11 were obtained in the same manner as in Example 1 except that the resin particle dispersion C-1 was changed to resin particle dispersions C-7 to C-10 as shown in Table 4. Table 4 shows the physical properties and evaluation of the toner.

  From Table 4, it can be seen that the electrostatic image developing toners of the examples both have a wide fixable area and storage stability, compared with the electrostatic charge image developing toners of the comparative examples, in a high temperature and high humidity environment. It can be seen that the charge holding performance is excellent.

  The toner for developing an electrostatic image of the present invention can be suitably used as a toner used in electrophotography because it has both a wide fixable area and storage stability and is excellent in charge retention performance in a high temperature and high humidity environment. . According to the production method of the present invention, a toner having such characteristics can be produced efficiently.

Claims (10)

Step (1): The resin particles (A) containing the crystalline polyester (a) and the amorphous polyester (b) and the release agent particles containing the release agent are aggregated to obtain aggregated particles (1). Process,
Step (2): Addition of resin particles (C) composed of a graft polymer composed of a main chain segment (A1) composed of a polyester resin and a side chain segment (A2) composed of an addition polymerization resin, and agglomerated particles (2 )
Step (3): Fusing the aggregated particles (2) to obtain core-shell particles,
A method for producing an electrostatic charge image developing toner comprising:
The toner for developing electrostatic images is, the crystalline polyester (a), a core containing an amorphous polyester (b) and the releasing agent contains a shell of the graft polymer, the segment (A1) and the segment (A2 ) Has a non-aromatic carbon-carbon unsaturated bond as a raw material monomer from which the constituent unit of segment (A1) is derived, and has a carboxy group at both ends. in the carboxylic acid component of the dicarboxylic acid segment (A1) having, 0 exceed mol% unrealized less than 20 mol%, the graft polymer is non-aromatic carbon in the main chain - amorphous carbon unsaturated bonds A step of preparing a polyester resin (c1), mixing the polyester resin (c1) with an aqueous medium to obtain an aqueous dispersion of the polyester resin (c1), and attaching the aqueous dispersion to the aqueous dispersion By adding a polymerizable monomer (c2) polymerized, it is obtained by a method comprising the step of obtaining an aqueous dispersion of the graft polymer, method for producing a toner for developing electrostatic images. The weight ratio of the crystalline polyester (a) and amorphous polyester (b) is (a) / (b) = 5 / 95~30 / 70, manufacture of the toner according to claim 1 Way . The dicarboxylic acid having a non-aromatic carbon-carbon unsaturated bond and having a carboxy group at both ends thereof is at least one selected from the group consisting of fumaric acid, maleic acid and tetrahydrophthalic acid. 3. A method for producing a toner for developing an electrostatic charge image according to 1 or 2. The electrostatic charge image developing toner according to any one of claims 1 to 3, wherein the addition polymerizable monomer derived from the structural unit of the addition polymerization resin comprises a styrene monomer and / or a (meth) acrylic acid ester . Manufacturing method . The method for producing a toner for developing an electrostatic charge image according to claim 4, wherein the addition polymerizable monomer is at least one selected from the group consisting of styrene, methylstyrene, benzyl methacrylate and benzyl acrylate. The crystalline polyester (a) is a crystalline polyester obtained by polycondensation of an α, ω-alkanediol having 4 to 12 carbon atoms and an aliphatic carboxylic acid having 8 to 12 carbon atoms. A method for producing a toner for developing an electrostatic image according to any one of the above. The method for producing a toner for developing an electrostatic charge image according to any one of claims 1 to 6, wherein the crystalline polyester (a) has a melting point of 60 to 90 ° C. The method for producing a toner for developing an electrostatic charge image according to any one of claims 1 to 7 , wherein the fusing temperature in the step (3) is a temperature not less than 10 ° C lower than the glass transition point of the graft polymer. The method for producing a toner for developing an electrostatic charge image according to any one of claims 1 to 8 , wherein the resin particles (A) contain a colorant. The method for producing a toner for developing an electrostatic charge image according to any one of claims 1 to 9, wherein the fusing temperature in the step (3) is a temperature not lower than the glass transition point of the graft polymer.