JP5952698B2 - Toner for electrostatic image development - Google Patents

Description

  The present invention relates to an electrostatic image developing toner 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 toner as a core-shell type in order to improve thermal characteristics such as thermal characteristics (low-temperature fixability) for fixing at low temperatures and offset resistance.

For example, Patent Document 1 discloses that an alcohol component containing an aliphatic diol having 2 to 12 carbon atoms and a fat having 8 to 12 carbon atoms are used for the purpose of improving low-temperature fixability, carrier contamination resistance, and charging rate. A crystalline polyester obtained by polycondensing a carboxylic acid component containing an aromatic dicarboxylic acid compound, an alcohol component, an alkyl (carbon number 9 to 18) succinic acid, and an alkenyl (carbon number 9 to 18) succinic acid. An alcohol containing an amorphous resin obtained by polycondensing a carboxylic acid component containing one kind of succinic acid compound, the shell portion containing a carboxylic acid component and an aliphatic dialcohol having 2 to 5 carbon atoms A toner binder resin composed of core-shell particles, which is an amorphous resin obtained by condensation polymerization of components, is disclosed.
Patent Document 2 discloses resin fine particles containing an amorphous polyester resin for the purpose of improving low-temperature fixability, heat-resistant storage stability, crushing resistance, and filming resistance, and suppressing generation of fine powder and toner scattering. A first agglomeration step for producing a dispersion of a first toner particle precursor, a dispersion of the first toner particle precursor, and a dispersion of polyester resin fine particles having a carboxyl group And a second agglomeration step for aggregating the second toner particle precursor to form toner particles, and a toner production method comprising: Has been.

JP 2011-197193 A JP 2010-145611 A

The electrostatic charge developing toner is required to further improve low-temperature fixability, heat-resistant storage stability and durability, and the toners of Patent Documents 1 and 2 cannot sufficiently meet the requirements.
An object of the present invention is to provide a toner for developing an electrostatic image having excellent low-temperature fixability, heat-resistant storage stability and durability, and a method for producing the same.

  The present inventors have considered the factors that affect the low-temperature fixability, heat-resistant storage stability, and durability of the toner are the monomer composition and physical properties of the core and shell constituting the core-shell toner. As a result, a toner for developing an electrostatic charge image comprising a specific component and containing an amorphous polyester having a specific softening point in the core and a specific amorphous polyester in the shell has low-temperature fixability and heat-resistant storage stability. And it discovered that it was excellent in durability.

That is, the present invention provides the following [1] and [2].
[1] An electrostatic charge image developing toner having a core and a shell, wherein the core is obtained by condensing an alcohol component containing an aliphatic diol and an acid component containing 5 mol% or more and 50 mol% or less of alkenyl succinic acid. The amorphous polyester (a) having a softening point of 75 ° C. or higher and 105 ° C. or lower obtained by polymerization is included, and the shell includes an alcohol component containing an aromatic diol and an acid component containing an aromatic carboxylic acid. Containing amorphous polyester (b) obtained by condensation polymerization, the content of aliphatic diol and aliphatic carboxylic acid in all monomers constituting the core polyester is 55 mol% or more, and constitutes the shell polyester A toner for developing an electrostatic charge image, wherein the content of aromatic diol and aromatic carboxylic acid in all monomers is 80 mol% or more.
[2] The method for producing an electrostatic charge image developing toner according to [1], comprising the following steps 1 to 4.
Step 1: Step of obtaining an aqueous dispersion of resin particles I containing amorphous polyester (a) Step 2: Step of obtaining an aqueous resin dispersion containing amorphous polyester (b) Step 3: Obtained in Step 1 A step of mixing an aqueous dispersion of resin particles I and a resin aqueous dispersion containing the amorphous polyester (b) obtained in step 2 to obtain an aqueous dispersion of resin particles II Step 4: Step 3 Step of uniting resin particles II obtained in step 1

  According to the present invention, it is possible to provide an electrostatic image developing toner excellent in low-temperature fixability, heat-resistant storage stability and durability, and a method for producing the same.

  The electrostatic image developing toner of the present invention is an electrostatic image developing toner having a core and a shell, and the core contains an alcohol component containing an aliphatic diol and alkenyl succinic acid in an amount of 5 mol% to 50 mol%. The amorphous polyester (a) having a softening point not lower than 75 ° C. and not higher than 105 ° C. obtained by condensation polymerization with an acid component contained below, and the shell includes an alcohol component containing an aromatic diol and an aromatic carboxyl Including an amorphous polyester (b) obtained by condensation polymerization of an acid component containing an acid, the content of aliphatic diol and aliphatic carboxylic acid in all monomers constituting the core polyester is 55 mol% or more And the content of the aromatic diol and aromatic carboxylic acid in all the monomers constituting the polyester of the shell is 80 mol% or more.

The reason why the electrostatic image developing toner of the present invention is excellent in low-temperature fixability, heat-resistant storage stability and durability is not clear, but is considered as follows.
In this specification, the aromatic diol component in the alcohol component constituting the polyester and the aromatic carboxylic acid component in the acid component are referred to as an aromatic monomer component, and the aliphatic in the alcohol component constituting the polyester. The diol component and the aliphatic carboxylic acid component in the acid component are collectively referred to as an aliphatic monomer component.
In the toner of the present invention, the content of the aliphatic diol and the aliphatic carboxylic acid in all monomers constituting the core polyester, that is, the content of the aliphatic monomer component is 55 mol% or more. Polyesters with a high content of these aliphatic monomer components are more flexible than polyesters with a high content of aromatic monomer components, and melt quickly at low temperatures to increase the ester bond portion of the main chain. Therefore, it is considered that hydrogen bonding with the paper also occurs, and it is considered that the low-temperature fixability is excellent.
Further, in the toner of the present invention, the content of aromatic diol and aromatic carboxylic acid in all monomers constituting the shell polyester, that is, the content of aromatic monomer component is 80 mol% or more. Polyesters with a high content of these aromatic monomer components have an aromatic ring, so that the resin is hardened and excellent in durability and heat resistant storage stability. In addition, since the core contains a lot of fatty monomer components and the shell contains a lot of aromatic monomer components, the core and shell are difficult to be compatible, so the core shell structure is sufficiently maintained and the above characteristics of the core and shell are maintained. Is sufficiently maintained. In addition, since both the core and the shell are polyester, they are sufficiently bonded to each other, and the core and the shell are prevented from being separated even under stress. Further, the content of alkenyl succinic acid in the alcohol component of the amorphous polyester (a) of the core is 5 mol% or more and 50 mol% or less, and since it contains a considerable amount of alkenyl succinic acid, the flexibility is high, It is considered that the alkenyl group melts rapidly at a lower temperature and appropriately prevents the compatibility between the shell and the core, thereby improving the low-temperature fixability, heat-resistant storage stability and durability of the toner. Furthermore, since the softening point of the amorphous polyester (a) constituting the core is 75 ° C. or higher and 105 ° C. or lower, the low temperature fixability can be improved without deteriorating the heat resistant storage stability and durability of the toner. Conceivable.
Hereinafter, each component and process used in the present invention will be described.

[core]
The core in the electrostatic image developing toner of the present invention comprises an alcohol component containing an aliphatic diol and an acid component containing 5 mol% or more and 50 mol% or less of alkenyl succinic acid from the viewpoint of low-temperature fixability of the toner. The amorphous diol (a) having a softening point of 75 ° C. or higher and 105 ° C. or lower obtained by condensation polymerization, and the content of aliphatic diol and aliphatic carboxylic acid in all monomers constituting the core polyester is It is 55 mol% or more.

[Amorphous polyester (a)]
The amorphous polyester (a) used in the present invention is obtained by condensation polymerization of an alcohol component containing an aliphatic diol and an acid component containing 5 mol% or more and 50 mol% or less of alkenyl succinic acid.
In the present invention, the amorphous polyester means that the ratio of the softening point to the endothermic maximum peak temperature (softening point (° C.) / Endothermic maximum peak temperature (° C.)) in the measurement method described in the examples described later is 1. .3 or less than 0.6, preferably greater than 1.3 and less than 4, more preferably 1.5-3.

[Alcohol component]
The alcohol component which is a raw material of the amorphous polyester (a) contains an aliphatic diol.
The aliphatic diol preferably contains an aliphatic diol having 2 to 6 carbon atoms from the viewpoint of improving the low-temperature fixability of the toner when used together with the alkenyl succinic acid contained in the acid component.
Among aliphatic diols having 2 to 6 carbon atoms, those having one or more secondary hydroxyl groups are preferable from the viewpoint of improving the heat resistant storage stability and durability of the toner.
Such aliphatic diols preferably have 3 to 6 carbon atoms and more preferably 3 to 4 carbon atoms from the viewpoint of improving the low-temperature fixability of the toner. Specific preferred examples of the C2-C6 aliphatic diol having one or more secondary hydroxyl groups include 1,2-propanediol, 1,2-butanediol, 1,3-butanediol, 2, 3-butanediol, 1,2-pentanediol, 1,3-pentanediol, 2,3-pentanediol, 2,4-pentanediol, 1,2-hexanediol, 1,3-hexanediol, 1,4 -Hexanediol, 1,5-hexanediol, etc. are mentioned. Among these, at least one selected from the group consisting of 1,2-propanediol and 2,3-butanediol is preferable from the viewpoint of improving the low-temperature fixability, heat-resistant storage stability and durability of the toner. 2-Propanediol is more preferred.

Other aliphatic diols having 2 to 6 carbon atoms include ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, and the like. Can be mentioned. Among these, neopentyl glycol and ethylene glycol are preferable from the viewpoint of low-temperature fixability of the toner.
When an aliphatic diol having 2 to 6 carbon atoms is used, the content of the aliphatic diol having 2 to 6 carbon atoms is preferably 80 mol% or more in the alcohol component from the viewpoint of low-temperature fixability of the toner. Preferably it is 80-100 mol%, More preferably, it is 90-100 mol%, More preferably, it is 95-100 mol%. In particular, the alcohol component preferably contains an aliphatic diol having 3 to 4 carbon atoms and having one or more secondary hydroxyl groups in a content within the numerical range.

Examples of the alcohol component other than the aliphatic diol having 2 to 6 carbon atoms include an aliphatic diol having 7 or more carbon atoms, a trivalent or higher alcohol such as glycerin, and an alkylene oxide adduct of bisphenol A.
Specific examples of alkylene oxide adducts of bisphenol A include polyoxypropylene adducts of 2,2-bis (4-hydroxyphenyl) propane and polyoxyethylene additions of 2,2-bis (4-hydroxyphenyl) propane And alkylene oxide adducts of bisphenol A.

[Acid component]
The acid component which is a raw material of the amorphous polyester (a) contains 5 to 50 mol% of alkenyl succinic acid.
In the present invention, the acid described in the acid component includes a free acid, an anhydride of these acids, and an alkyl group having 1 to 3 carbon atoms that can be used as a raw material for producing the polyester. Having an alkyl ester.

《Alkenyl succinic acid》
The carbon number of the alkenyl group in the alkenyl succinic acid is preferably 9 or more and 18 or less, more preferably 9 or more and 14 or less, and still more preferably, from the viewpoints of low-temperature fixability, heat-resistant storage stability and durability of the toner. 10 or more and 13 or less.
These alkenyl groups may be linear or branched, but are preferably branched from the viewpoint of low-temperature fixability, heat-resistant storage stability and durability of the toner.
Further, from the viewpoint of low-temperature fixability, heat-resistant storage stability, and durability of the toner, the alkenyl succinic acid is preferably composed of two or more types. The “kind” referred to here is derived from an alkenyl group, and alkenyl groups having different carbon chain lengths and structural isomers are treated as different types of alkenyl succinic acid.

Therefore, alkenyl succinic acid is preferably a branch having 9 to 18 carbon atoms, more preferably 9 to 14 carbon atoms, and still more preferably 10 to 13 carbon atoms, from the viewpoint of low-temperature fixability, heat-resistant storage stability and durability of the toner. What consists of 2 or more types of the alkenyl succinic acid which has a chain | strand alkenyl group is preferable. By using alkenyl succinic acid (a1) having a branched alkenyl group having a different carbon number, the obtained resin has a broad endothermic peak near the glass transition temperature in differential scanning calorimetry (DSC). The binder resin has a very wide fixing temperature range.
Specific examples of the alkenyl group having 9 to 18 carbon atoms having a branched chain include an isododecenyl group.

  From the viewpoint of low-temperature fixability, heat-resistant storage stability and durability of the toner, the alkenyl succinic acid is at least one selected from a compound having an alkylene group (alkylene compound), maleic acid, fumaric acid and acid anhydrides thereof. It is preferable that it is obtained from these.

  As the alkylene compound, those having 9 to 18 carbon atoms, more preferably 9 to 14 carbon atoms, still more preferably 10 to 12 carbon atoms are preferable from the viewpoint of low-temperature fixability, heat-resistant storage stability and durability of the toner. Specifically, those obtained from ethylene, propylene, isobutylene, normal butylene and the like, for example, trimers and tetramers thereof are preferably used. As a suitable raw material used for the synthesis of the alkylene compound, propylene having a low molecular weight is preferable from the viewpoint of increasing the number of structural isomers. In addition, the alkylene compound is a polycondensation resin obtained by using alkenyl succinic acid, as a binder resin for toner, and has a very wide fixing temperature range. And preferably having 2 or more peaks corresponding to an alkylene compound having 9 to 18 carbon atoms, preferably 9 to 14 carbon atoms, more preferably 10 or more, still more preferably 20 or more, still more preferably 30 or more, and 80 The following is preferable, and 60 or less is more preferable.

  In the acid component of the amorphous polyester (a), alkenyl succinic acid is contained in an amount of 5 mol% or more and 50 mol% or less, and preferably 5 mol% or more, more preferably 7 mol%, from the viewpoint of storage stability and durability of the toner. More preferably, it is 10 mol% or more, preferably 40 mol% or less, more preferably 30 mol% or less, still more preferably 20 mol% or less, preferably 5 to 40 mol%, preferably 7 to 30 mol%. More preferably, mol% is more preferable, and 10-20 mol% is still more preferable.

<< Method for Producing Alkenyl Succinic Acid >>

The alkenyl succinic acid can be obtained by an arbitrary production method. For example, an alkylene compound and at least one selected from maleic acid, fumaric acid and acid anhydrides thereof are mixed and heated to obtain an ene succinic acid. It can be obtained by utilizing a reaction (see JP-A-48-23405, JP-A-48-23404, US Pat. No. 3,374,285, etc.).
Among maleic acid, fumaric acid and acid anhydrides thereof, maleic anhydride is preferable from the viewpoint of reactivity.
Suitable catalysts used for the synthesis of the alkylene compound include liquid phosphoric acid, solid phosphoric acid, tungsten, boron trifluoride complex and the like. From the viewpoint of ease of control of the number of structural isomers, a method of adjusting by distillation after random polymerization is preferred.

<< Carboxylic acid components other than alkenyl succinic acid >>
In addition to alkenyl succinic acid, the acid component may contain one or more of alkyl succinic acid, other dicarboxylic acids, and trivalent or higher carboxylic acids.
The number of carbon atoms of the alkyl group of the alkyl succinic acid and the presence or absence of branching are the same as those of the alkenyl group of the alkenyl succinic acid, and isododecyl group is preferable.

  Other dicarboxylic acids include oxalic acid, malonic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, succinic acid, adipic acid, sebacic acid, azelaic acid and other aliphatic dicarboxylic acids; phthalic acid, isophthalic acid Examples thereof include aromatic dicarboxylic acids such as acid and terephthalic acid; and alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid. Of these, aliphatic dicarboxylic acids and aromatic dicarboxylic acids are preferred, and aromatic dicarboxylic acids are more preferred from the viewpoint of low-temperature fixability, heat-resistant storage stability, and charge stability of the toner. Specifically, at least one of fumaric acid, isophthalic acid and terephthalic acid is preferable, at least one of isophthalic acid and terephthalic acid is more preferable, and terephthalic acid is still more preferable.

Examples of the trivalent or higher carboxylic acids include aromatic carboxylic acids such as 1,2,4-benzenetricarboxylic acid (trimellitic acid), 2,5,7-naphthalenetricarboxylic acid, and pyromellitic acid.
Examples of other acids include unpurified rosin, purified rosin, and rosin modified with fumaric acid, maleic acid, acrylic acid, and the like.

  In the present invention, the acid component contains a trivalent or higher carboxylic acid, preferably trimellitic acid, more preferably trimellitic anhydride, from the viewpoint of increasing the molecular weight of the resin and improving the heat resistant storage stability of the toner. It is preferable. The content of the trivalent or higher carboxylic acid in the acid component is preferably 0.1 mol% or more, more preferably 1 mol% or more, still more preferably 2 mol% or more, and even more preferably 5 mol% or more. Moreover, it is preferably 30 mol% or less, more preferably 25 mol% or less, still more preferably 20 mol% or less, still more preferably 15 mol% or less, preferably 0.1 to 30 mol%, preferably 1 to 25 mol%. More preferably, mol% is more preferable, 2-20 mol% is still more preferable, and 5-15 mol% is still more preferable.

  The acid component preferably contains an aromatic dicarboxylic acid from the viewpoint of low-temperature fixability, heat-resistant storage stability, and charge stability of the toner. In the acid component, the content of the aromatic dicarboxylic acid is preferably 50 mol% or more, more preferably 60 mol% or more, still more preferably 65 mol% or more, and still more preferably 70 mol% or more, from the same viewpoint. And preferably 90 mol% or less, more preferably 80 mol% or less, preferably 50 to 90 mol%, more preferably 60 to 90 mol%, still more preferably 65 to 80 mol%, and more More preferably, it is 70-80 mol%.

[shell]
The shell in the toner for developing an electrostatic image of the present invention is formed by condensing an alcohol component containing an aromatic diol and an acid component containing an aromatic carboxylic acid from the viewpoint of low temperature fixability, heat resistant storage stability and durability of the toner. The content of the aromatic diol and the aromatic carboxylic acid in all monomers constituting the shell is 80 mol% or more, including the amorphous polyester (b) obtained by polymerization.

[Amorphous polyester (b)]
The amorphous polyester (b) is obtained by condensation polymerization of an alcohol component containing an aromatic diol and an acid component containing an aromatic carboxylic acid.

[Alcohol component]
The alcohol component which is a raw material of the amorphous polyester (b) contains an aromatic diol.

  Examples of the aromatic diol include an alkylene oxide adduct of bisphenol A represented by the following (1) from the viewpoint of low-temperature fixability, heat-resistant storage stability and durability of the toner.

(In the formula, RO and OR are oxyalkylene groups, R is an ethylene and / or propylene group, and the average value of the sum of x and y per molecule is preferably 1-16, more preferably 1-8. 1.5 to 4 are more preferable.)

  Specific examples of the alkylene oxide adduct of bisphenol A represented by the formula (I) include 2,2-bis (4-hydroxyphenyl) propane polyoxypropylene adduct and 2,2-bis (4- Hydroxyphenyl) propane polyoxyethylene adduct and the like.

  The content of the alkylene oxide adduct of bisphenol A is preferably 60 mol% or more, preferably 80 to 100 mol% of the alkylene oxide adduct of bisphenol A in the alcohol component from the viewpoint of heat-resistant storage stability and durability of the toner. Is more preferable, 90-100 mol% is still more preferable, and 95-100 mol% is still more preferable.

  Examples of alcohol components other than aromatic diols include the aliphatic diols and trihydric or higher alcohols.

[Acid component]
The acid component that is a raw material of the amorphous polyester (b) contains an aromatic carboxylic acid.
The aromatic carboxylic acid is preferably an aromatic dicarboxylic acid, and more preferably both an aromatic dicarboxylic acid and a trivalent or higher valent aromatic carboxylic acid, from the viewpoint of heat-resistant storage stability and durability of the toner.
The aromatic dicarboxylic acid is preferably isophthalic acid or terephthalic acid.
The trivalent or higher valent aromatic carboxylic acid is preferably 1,2,4-benzenetricarboxylic acid (trimellitic acid), 2,5,7-naphthalenetricarboxylic acid, pyromellitic acid, and increases the molecular weight of the resin. From the viewpoint of heat-resistant storage stability and durability of the toner, it is more preferable to contain a trimellitic acid compound, more preferably trimellitic anhydride.
In the acid component, the content of the aromatic carboxylic acid is preferably 60 mol% or more, more preferably 70 to 100 mol%, still more preferably 90 to 100 mol, from the viewpoint of heat-resistant storage stability and durability of the toner. %, More preferably 95 to 100 mol%.
In the acid component, the content of the aromatic dicarboxylic acid is preferably 60 mol% or more, more preferably 65 mol% or more, still more preferably 70 mol% or more, from the viewpoint of heat-resistant storage stability and durability of the toner. And preferably 90 mol% or less, more preferably 85 mol% or less, still more preferably 80 mol% or less, more preferably 60 to 90 mol%, still more preferably 65 to 85 mol%, and more More preferably, it is 70-80 mol%.
In the acid component, the content of the trivalent or higher aromatic carboxylic acid is preferably 5 mol% or more, more preferably 10 mol%, from the viewpoint of low temperature fixability, heat resistant storage stability and durability of the toner in the acid component. More preferably, it is 20 mol% or more, preferably 40 mol% or less, more preferably 30 mol% or less, preferably 5 to 40 mol%, more preferably 10 to 30 mol%, more preferably 20 to 20 mol%. 30 mol% is still more preferable.

  Examples of the acid component other than aromatic carboxylic acid include alkenyl succinic acid, alkyl succinic acid, alkenyl succinic acid, aliphatic dicarboxylic acid other than alkyl succinic acid, alicyclic dicarboxylic acid, and the like. Among them, alkenyl succinic acid And aliphatic dicarboxylic acids other than alkyl succinic acid are preferred.

[Crystalline polyester]
In order to improve the low-temperature fixability of the toner, the toner of the present invention may contain a crystalline polyester to the extent that the effects of the present invention are not impaired.
When the crystalline polyester is contained, it is preferably contained in the core from the viewpoint of low-temperature fixability, heat-resistant storage stability and durability of the toner.
The kind of alcohol component of the crystalline polyester is the same as the alcohol component of the amorphous polyester (a). From the viewpoint of improving the crystallinity of the resin and improving the low-temperature fixability of the toner, 1,6-hexane is used. Diols are more preferred. The kind of the acid component of the crystalline polyester is the same as the acid component of the amorphous polyester (a), and fumaric acid is more preferable from the viewpoint of improving the low-temperature fixability of the toner.
In the present invention, the crystalline polyester refers to a polyester other than the amorphous polyester. Specifically, the ratio of the softening point to the maximum endothermic peak temperature (softening point (° C.) / Maximum endothermic peak temperature (° C. )) Refers to a polyester of 0.6 to 1.3, preferably 0.9 to 1.2, more preferably 1.0 to 1.2.

The softening point of the crystalline polyester used in the present invention is preferably 60 ° C. or higher, more preferably 80 ° C. or higher, and still more preferably 100 ° C. or higher, from the viewpoint of low-temperature fixability, heat-resistant storage stability and durability of the toner. More preferably, it is 110 ° C. or higher, preferably 140 ° C. or lower, more preferably 130 ° C. or lower, still more preferably 120 ° C. or lower, preferably 60 to 160 ° C., more preferably 80 to 140 ° C. Preferably, 100-120 degreeC is further more preferable, and 110-120 degreeC is still more preferable.
The melting point of the crystalline polyester used in the present invention is preferably 60 to 150 ° C., more preferably 80 to 130 ° C., still more preferably 100 to 120 ° C., from the viewpoints of low-temperature fixability, heat-resistant storage stability and durability of the toner. More preferably, it is 105-115 degreeC.
The acid value of the crystalline polyester is preferably 1 to 40 mgKOH / g from the viewpoint of improving the dispersibility of the crystalline polyester particles in the aqueous dispersion, the low temperature fixability of the toner, and the charging stability. 35 mgKOH / g is more preferable, and 20-30 mgKOH / g is still more preferable.

[Production method of polyester]
There are no particular limitations on the method for producing the polyester, that is, the amorphous polyester (a), the amorphous polyester (b), and the crystalline polyester, and the polyester can be produced by a known method. It is obtained by a condensation polymerization reaction with an acid component. The polycondensation reaction is preferably performed in the presence of an esterification catalyst, and is more preferably performed in the presence of an esterification catalyst and a pyrogallol compound from the viewpoints of reactivity, molecular weight adjustment, and resin physical property adjustment.

[Esterification catalyst]
Examples of the esterification catalyst suitably used for the condensation polymerization include a titanium compound and a tin (II) compound having no Sn-C bond, and these may be used alone or in combination of two or more. it can.

  As a titanium compound, the titanium compound which has a Ti-O bond is preferable, and the compound which has a C1-28 total carbon number alkoxy group, an alkenyloxy group, or an acyloxy group is more preferable.

  Examples of the tin (II) compound having no Sn—C bond include a tin (II) compound having a Sn—O bond, a tin (II) compound having a Sn—X (X represents a halogen atom) bond, and the like. Preferred is a tin (II) compound having a Sn-O bond, and among them, a dioctylic acid tin (II) salt is more preferable from the viewpoints of reactivity, molecular weight adjustment, and resin physical property adjustment.

  The abundance of the esterification catalyst is preferably 0.01 to 1 part by mass with respect to 100 parts by mass of the total amount of the alcohol component and the carboxylic acid component, from the viewpoint of reactivity, molecular weight adjustment, and resin physical property adjustment. More preferably, it is 1 to 0.6 parts by mass.

[Pyrogallol compound]
A pyrogallol compound has a benzene ring in which three hydrogen atoms adjacent to each other are substituted with a hydroxyl group, and pyrogallol, gallic acid, gallic acid ester, 2,3,4-trihydroxybenzophenone, 2,2 ′, Examples include benzophenone derivatives such as 3,4-tetrahydroxybenzophenone, catechin derivatives such as epigallocatechin and epigallocatechin gallate, and gallic acid is preferred from the viewpoint of reactivity.
The abundance of the pyrogallol compound in the condensation polymerization reaction is preferably 0.001 to 1 part by mass with respect to 100 parts by mass of the total amount of the alcohol component and carboxylic acid component subjected to the condensation polymerization reaction, from the viewpoint of reactivity. 0.005-0.4 mass part is more preferable, and 0.01-0.2 mass part is still more preferable. Here, the abundance of the pyrogallol compound means the total amount of the pyrogallol compound subjected to the condensation polymerization reaction.
From the viewpoint of reactivity, the mass ratio of the pyrogallol compound to the esterification catalyst (pyrogallol compound / esterification catalyst) is preferably 0.01 to 0.5, more preferably 0.02 to 0.3, and 0.03. -0.2 is still more preferable.

The polycondensation reaction between the alcohol component and the carboxylic acid component can be performed, for example, in the presence of the esterification catalyst in an inert gas atmosphere at a temperature of 120 to 250 ° C, preferably 140 to 240 ° C.
In addition, for example, all monomers are charged together to increase the strength of the resin, or divalent monomers are first reacted to reduce low molecular weight components, and then trivalent or higher monomers are added and reacted. The method is preferably used. It is also preferable to accelerate the reaction by reducing the pressure of the reaction system in the latter half of the polymerization.

<Physical properties of core and shell>
The softening point of the amorphous polyester (a) is 75 ° C. or higher and 105 ° C. or lower, preferably 80 ° C. or higher, more preferably 90 ° C. or higher, from the viewpoint of low temperature fixability, heat resistant storage stability and durability of the toner. In addition, it is preferably 105 ° C. or lower, more preferably 100 ° C. or lower, preferably 80 to 105 ° C., and more preferably 90 to 100 ° C.
The number average molecular weight of the amorphous polyester (a) is preferably 1,000 to 5,000, more preferably 2,000 to 4,000, from the viewpoints of low-temperature fixability, heat-resistant storage stability and durability of the toner. More preferably, it is 3,000-3,500, and a weight average molecular weight is 6,000-30,000, More preferably, it is 9,000-20,000, More preferably, it is 10,000-15,000.
The softening point of the amorphous polyester (b) is preferably 100 ° C. or higher, more preferably 105 ° C. or higher, further preferably 120 ° C. or higher, from the viewpoint of low-temperature fixability and heat-resistant storage stability of the toner. The temperature is preferably 140 ° C. or lower, more preferably 135 ° C. or lower, still more preferably 130 ° C. or lower, preferably 100 to 140 ° C., more preferably 105 to 135 ° C., and still more preferably 120 to 130 ° C.
The number average molecular weight of the amorphous polyester (b) is preferably 1,000 to 5,000, more preferably 3,000 to 3,500, from the viewpoints of low temperature fixability, heat resistant storage stability and durability of the toner. The weight average molecular weight is 8,000 to 30,000, more preferably 12,000 to 20,000.
In the toner of the present invention, it is preferable that the softening point of the polyester constituting the shell is higher than the softening point of the polyester constituting the core from the viewpoints of low-temperature fixability, heat-resistant storage stability and durability of the toner. The difference in softening point between the polyester and the polyester constituting the shell is preferably 2 ° C. or higher, more preferably 5 ° C. or higher, still more preferably 20 ° C. or higher, still more preferably 25 ° C. or higher, and preferably 40 ° C. or less, more preferably 30 ° C. or less, preferably 2 to 40 ° C., more preferably 5 to 40 ° C., further preferably 20 to 40 ° C., and still more preferably 25 to 30 ° C. .
Further, from the viewpoint of low-temperature fixability, heat-resistant storage stability and durability of the toner, it is preferable that the softening point of the amorphous polyester (b) is higher than the softening point of the amorphous polyester (a). The difference in softening point between (a) and the amorphous polyester (b) is preferably 2 ° C or higher, more preferably 5 ° C or higher, still more preferably 20 ° C or higher, still more preferably 25 ° C or higher, Moreover, it is preferably 40 ° C. or less, more preferably 30 ° C. or less, preferably 2 to 40 ° C., more preferably 5 to 40 ° C., further preferably 20 to 40 ° C., and further preferably 25 to 30 ° C. Is even more preferable.

In the toner of the present invention, the glass transition temperature of the polyester constituting the core is preferably 30 ° C. or higher, more preferably 35 ° C. or higher, from the viewpoint of low-temperature fixability, heat-resistant storage stability and durability of the toner. Preferably it is 60 degrees C or less, More preferably, it is 50 degrees C or less, More preferably, it is 45 degrees C or less, Preferably it is 30-60 degreeC, More preferably, it is 35-50 degreeC, More preferably, it is 35-45 degreeC.
The glass transition temperature of the polyester constituting the shell is preferably 45 ° C. or higher, more preferably 60 ° C. or higher, and still more preferably 65 ° C. or higher, from the viewpoints of low temperature fixability, heat resistant storage stability and durability of the toner. Moreover, Preferably it is 75 degrees C or less, Preferably it is 45-75 degreeC, More preferably, it is 60-75 degreeC, More preferably, it is 65-75 degreeC.
The glass transition temperature of the amorphous polyester (a) is preferably 30 ° C. or higher, more preferably 35 ° C. or higher, from the viewpoint of low-temperature fixability, heat-resistant storage stability and durability of the toner. It is 60 ° C. or lower, more preferably 50 ° C. or lower, still more preferably 45 ° C. or lower, preferably 30 to 60 ° C., more preferably 35 to 50 ° C., and still more preferably 35 to 45 ° C.
The glass transition temperature of the amorphous polyester (b) is preferably 45 ° C. or higher, more preferably 60 ° C. or higher, and still more preferably 65 ° C. or higher, from the viewpoint of low-temperature fixability, heat-resistant storage stability and durability of the toner. Moreover, Preferably it is 75 degrees C or less, Preferably it is 45-75 degreeC, More preferably, it is 60-75 degreeC, More preferably, it is 65-75 degreeC.
The acid values of the amorphous polyester (a) and the amorphous polyester (b) are each independently 10 to 40 mgKOH / g from the viewpoint of improving the dispersibility of the amorphous resin particles in the aqueous dispersion. Preferably, 15-30 mgKOH / g is more preferable, and 15-28 mgKOH / g is still more preferable.
The softening point, glass transition temperature, and acid value can be adjusted by selecting the raw material composition, molecular weight, catalyst amount, etc., or reaction conditions.

[Toner for electrostatic image development]
The electrostatic image developing toner of the present invention is an electrostatic image developing toner having a core and a shell, and the core contains an alcohol component containing an aliphatic diol and 5 to 50 mol% of alkenyl succinic acid. The amorphous polyester (a) having a softening point of 75 to 105 ° C. obtained by polycondensation with an acid component is contained, and the shell contains an alcohol component containing an aromatic diol and an aromatic carboxylic acid. An amorphous polyester (b) obtained by polycondensation with an acid component, the content of aliphatic diol and aliphatic carboxylic acid in all monomers constituting the core polyester is 55 mol% or more, and the shell The toner for developing an electrostatic image in which the content of aromatic diol and aromatic carboxylic acid in all monomers constituting the polyester is 80 mol% or more.

The resin constituting the core may contain other resins in addition to the amorphous polyester (a) as long as the effects of the present invention are not impaired. Examples thereof include crystalline polyesters, other polyesters, styrene resins such as styrene-acrylic resins, resins such as epoxy resins, polycarbonates, and polyurethanes.
In the core, the content of the amorphous polyester (a) is preferably 50% by mass or more, and 70% by mass or more in the resin constituting the core from the viewpoint of low-temperature fixability, heat-resistant storage stability and durability of the toner. Is more preferable, 80 mass% or more is more preferable, 90 mass% or more is still more preferable, and it is still more preferable that it is substantially 100 mass%.
Moreover, the resin which comprises a shell may contain other resin in the range which does not impair the effect of this invention other than amorphous polyester (b). Examples thereof include other polyesters, styrene resins such as styrene-acrylic resins, and resins such as epoxy resins, polycarbonates, and polyurethanes.
In the shell, the content of the amorphous polyester (b) is preferably 50% by mass or more, and 70% by mass or more in the resin constituting the shell from the viewpoints of low-temperature fixability, heat-resistant storage stability and durability of the toner. Is more preferable, 80 mass% or more is more preferable, 90 mass% or more is still more preferable, and it is still more preferable that it is substantially 100 mass%.

In the toner for developing an electrostatic charge image of the present invention, the mass ratio of the polyester constituting the core and the polyester constituting the shell is 100/10 to 100/70 from the viewpoint of low temperature fixability, heat resistant storage stability and durability of the toner. Is preferable, 100/20 to 100/70 is more preferable, 100/20 to 100/50 is still more preferable, and 100/20 to 100/40 is still more preferable.
That is, the mass ratio (a) / (b) of the amorphous polyester (a) to the amorphous polyester (b) is 100/10 to 100 from the viewpoint of low-temperature fixability, heat-resistant storage stability and durability of the toner. / 70 is preferable, 100/20 to 100/70 is more preferable, and 100/20 to 100/50 is still more preferable.

〔Release agent〕
In the electrostatic image developing toner of the present invention, it is preferable that the core contains a release agent.
When the release agent is used, the mass ratio of the release agent to the resin constituting the core [release agent / resin constituting the core] is 0. 0 from the viewpoint of low-temperature fixability, heat resistant storage stability and durability of the toner. 1/100 to 10/100 is preferable, 0.5 / 100 to 5/100 is more preferable, and 1/100 to 3/100 is still more preferable.
The mass ratio of the release agent to the total amount of the amorphous polyesters (a) and (b) in the toner for developing an electrostatic charge image of the present invention [release agent / amorphous polyester [(a) + (b)]] is From the viewpoint of low-temperature fixability, heat-resistant storage stability and durability of the toner, 0.1 / 100 to 10/100 is preferable, 0.5 / 100 to 5/1000 is more preferable, and 1/100 to 2/100 is preferable. Further preferred.
Release agents include low molecular weight polyolefins such as polyethylene, polypropylene and polybutene; silicone waxes; fatty acid amides such as oleic acid amides; carnauba wax, rice wax, candelilla wax, wood wax, jojoba oil, etc. Plant waxes; animal waxes such as beeswax; mineral and petroleum waxes such as montan wax, paraffin wax, ozokerite, ceresin, microcrystalline wax, and Fischer-Tropsch wax. Among these, paraffin wax is preferable from the viewpoint of availability. These mold release agents can be used alone or in combination of two or more.

[Method for producing toner for developing electrostatic image]
The electrostatic image developing toner of the present invention can be produced by a production method having the following steps 1 to 4.
Step 1: Step of obtaining an aqueous dispersion of resin particles I containing amorphous polyester (a) Step 2: Step of obtaining an aqueous resin dispersion containing amorphous polyester (b) Step 3: Obtained in Step 1 A step of mixing an aqueous dispersion of resin particles I and a resin aqueous dispersion containing the amorphous polyester (b) obtained in step 2 to obtain an aqueous dispersion of resin particles II Step 4: Step 3 Step of coalescing the resin particles II obtained in 1) By the above method, the electrostatic image developing toner having the core-shell structure can be efficiently produced.

[Step 1]
Step 1 is a step of obtaining an aqueous dispersion of resin particles I containing amorphous polyester (a).
There is no limitation on the method for obtaining an aqueous dispersion of resin particles I, and a method, monomer solution or amorphous method for obtaining an aqueous dispersion of resin particles I by aggregating an aqueous resin dispersion containing amorphous polyester (a). A method of dispersing a monomer solution containing a porous polyester (a) in an aqueous medium and obtaining an aqueous dispersion of resin particles I by suspension polymerization, an amorphous polyester (a) or a solution containing an amorphous polyester (a) Can be dispersed in an aqueous medium to obtain an aqueous dispersion of resin particles I. From the viewpoint of obtaining resin particles having a narrow particle size distribution, the aqueous resin dispersion containing amorphous polyester (a) is agglomerated. To obtain an aqueous dispersion of the resin particles I is preferable. Hereinafter, the method will be described.
In the present specification, the “aqueous dispersion” means that the medium in which the resin is dispersed may contain a solvent such as an organic solvent, but water is preferably 50% by mass or more, more preferably 70% by mass or more. More preferably, it is 90% by mass or more, more preferably 99% by mass or more, and still more preferably 100% by mass. Further, hereinafter, when simply described as “resin”, it refers to both amorphous polyester and any other resin.

<Preparation of resin aqueous dispersion containing amorphous polyester (a)>
The resin aqueous dispersion containing the amorphous polyester (a) is prepared by mixing the amorphous polyester (a), an organic solvent and water, and further, if necessary, a neutralizing agent and a surfactant, stirring, distillation, etc. Is preferably obtained by removing the organic solvent. Preferably, after the amorphous polyester (a) and, if necessary, the surfactant are dissolved in an organic solvent, water and, if necessary, a neutralizing agent are mixed. In addition, when stirring a mixture, arbitrary mixing stirring apparatuses, such as an anchor wing | blade, can be used.

Organic solvents include alcohol solvents such as ethanol, isopropanol and isobutanol; ketone solvents such as acetone, 2-butanone, methyl ethyl ketone, methyl isobutyl ketone and diethyl ketone; ether solvents such as dibutyl ether, tetrahydrofuran and dioxane; acetic acid Ethyl is mentioned. Among these, from the viewpoint of dispersibility of the amorphous polyester (a), methyl ethyl ketone, ethyl acetate, and 2-butanone are preferable, and methyl ethyl ketone is more preferable.
Examples of the neutralizing agent include alkali metals such as lithium hydroxide, sodium hydroxide and potassium hydroxide; organic bases such as ammonia, trimethylamine, ethylamine, diethylamine, triethylamine, triethanolamine and tributylamine. From the viewpoint of workability, sodium hydroxide is preferable.
Examples of the surfactant include anionic surfactants such as sulfate ester, sulfonate, phosphate, and soap (such as alkyl ether carboxylate); amine salt type and quaternary ammonium salt Type cationic surfactants; polyoxyethylene alkyl aryl ethers such as polyoxyethylene nonylphenyl ether, polyoxyethylene alkyl ethers such as polyoxyethylene oleyl ether and polyoxyethylene lauryl ether, polyoxyethylene sorbitan mono Polyoxyethylene sorbitan esters such as laurate and polyoxyethylene sorbitan monostearate, polyethylene glycol monolaurate, polyethylene glycol monostearate and polyethylene glycol monoole Polyoxyethylene fatty acid esters over preparative like, nonionic surfactants such as polyoxyethylene / polyoxypropylene block copolymers, and the like. When using a surfactant, the amount used is from the viewpoint of dispersibility of the amorphous polyester (a) with respect to 100 parts by mass of all the resins used in this step including the amorphous polyester (a). The amount is preferably 0.1 to 20 parts by mass, more preferably 0.5 to 10 parts by mass.

The amount of the organic solvent to be mixed with the resin containing the amorphous polyester (a) is, from the viewpoint of the solubility of the amorphous polyester (a), all resins used in this step containing the amorphous polyester (a). 100-1000 mass parts is preferable with respect to 100 mass parts, and 150-500 mass parts is more preferable. The amount of water mixed with all the resins used in this step, including the amorphous polyester (a), is 100 to 1000 parts by mass with respect to 100 parts by mass of the organic solvent from the viewpoint of resin dispersibility. Preferably, 150-500 mass parts is more preferable.
The temperature at which the amorphous polyester (a) and the organic solvent are mixed is preferably 30 to 90 ° C, more preferably 40 to 80 ° C, from the viewpoint of the solubility of the amorphous polyester (a).
The solid content concentration of the aqueous dispersion of the amorphous polyester (a) is preferably 3 to 50% by mass, more preferably 5 from the viewpoint of dispersibility of the amorphous polyester (a) by appropriately adding water. It adjusts to -30 mass%, More preferably, it is 7-15 mass%.

  The volume median particle size of the resin particles containing the amorphous polyester (a) in the aqueous dispersion is preferably from 50 to 1,000 nm, preferably from 50 to 500 nm, from the viewpoint of uniform aggregation in the subsequent aggregation step. Is more preferable, 50-400 nm is still more preferable, and 100-350 nm is still more preferable. The volume median particle size can be measured by the method described in the examples.

<Preparation of resin aqueous dispersion containing crystalline polyester>
The resin aqueous dispersion containing crystalline polyester can also be produced in the same manner as the resin aqueous dispersion containing amorphous polyester (a), and the preferred range is also the same.

<Preparation of aqueous dispersion of resin particles I (aggregation step)>
Next, the resin aqueous dispersion containing the amorphous polyester (a) and, if necessary, the aqueous dispersion of the release agent and / or the resin aqueous dispersion containing the crystalline polyester are mixed and then aggregated. An aqueous dispersion of resin particles I is obtained.
In addition, the resin aqueous dispersion containing the above amorphous polyester (a) is further added to, for example, a colorant, a charge control agent, a conductivity regulator, an extender pigment, a reinforcing filler such as a fibrous substance, an antioxidant, and You may make it aggregate after adding additives, such as anti-aging agent. The additive can also be used as an aqueous dispersion.
Further, in the aggregating step, an aggregating agent can be added in order to effectively agglomerate.
≪Release agent≫
The release agent is preferably used as a release agent particle dispersion liquid dispersed in an aqueous medium from the viewpoint of dispersibility and cohesiveness with resin particles.
The addition amount of the release agent is from the viewpoint of dispersibility in the resin and the high-temperature offset resistance of the toner with respect to 100 parts by mass of the total amount of resin used in the core containing the amorphous polyester (a). 0.1-10 mass parts is preferable, 0.5-10 mass parts is more preferable, 0.5-5 mass parts is still more preferable, and 1-3 mass parts is still more preferable. The mass ratio of the release agent and the resin in this step, that is, the resin constituting the core is as described above.

≪Colorant≫
There is no restriction | limiting in particular as a coloring agent, A well-known coloring agent is mentioned, According to the objective, it can select suitably. Specifically, carbon black, inorganic composite oxide, chrome yellow, hansa yellow, benzidine yellow, selenium yellow, quinoline yellow, permanent orange GTR, pyrazolone orange, vulcan orange, watch young red, permanent red, brilliantamine 3B, Brilliantamine 6B, DuPont Oil Red, Pyrazolone Red, Resol Red, Rhodamine B Lake, Lake Red C, Bengal, Aniline Blue, Ultramarine Blue, Calco Oil Blue, Methylene Blue Chloride, Phthalocyanine Blue (Copper Phthalocyanine), Phthalocyanine Green, and Malachite Various pigments such as green oxalate; acridine, xanthene, azo, benzoquinone, azine, anthraquino System, indigo, thioindigo, phthalocyanine, aniline black, polymethine, triphenylmethane dyes, diphenylmethane dyes, thiazine, and include various dyes of thiazole, and the like. These can be used alone or in combination of two or more. When adding a coloring agent, the addition amount is 0.1-20 mass parts with respect to 100 mass parts of total amount of resin used for the core containing an amorphous polyester (a) from a viewpoint of image quality improvement. 1-10 mass parts is more preferable, and 5-10 mass parts is still more preferable.

≪Charge control agent≫
Examples of the charge control agent include a chromium-based azo dye, an iron-based azo dye, an aluminum azo dye, and a salicylic acid metal complex. A salicylic acid metal complex is preferable from the viewpoint of charge stability and availability of the toner. . Various charge control agents may be used alone or in combination of two or more. When the charge control agent is added, the addition amount is 0.1 to 8 parts by mass with respect to 100 parts by mass of the total amount of resin used for the core containing the amorphous polyester (a) from the viewpoint of improving the image quality. Is preferable, 0.3-7 mass parts is more preferable, and 0.8-3 mass parts is still more preferable.

≪Flocculant≫
As the aggregating agent, a quaternary ammonium salt cationic surfactant, polyethyleneimine, or the like is used in the organic system, and an inorganic metal salt, an inorganic ammonium salt, a divalent or higher metal complex, or the like is used in the inorganic system. . Among these, from the viewpoint of causing uniform aggregation, an organic flocculant is preferable, a cationic surfactant is more preferable, and a quaternary ammonium salt is further preferable.
When the flocculant is added, the addition amount is preferably 60 parts by mass or less, more preferably 30 parts by mass or less, with respect to 100 parts by mass of the resin used in this step, from the viewpoint of environmental resistance characteristics of the toner. More preferred is less than or equal to parts by weight. Moreover, 0.1 mass part or more is preferable and 1 mass part or more is more preferable.
In order to cause uniform agglomeration, the flocculant is preferably added after being dissolved in an aqueous medium, and is preferably sufficiently stirred at the time of addition of the flocculant and after completion of the addition.

<Various conditions in the system>
In the aggregation step, the solid content concentration in the system is preferably 5 to 50% by mass, more preferably 5 to 30% by mass, and still more preferably 5 to 20% by mass in order to cause uniform aggregation.

The pH in the system in the aggregation step is preferably 2 to 10, more preferably 2 to 9, and still more preferably 3 to 8, from the viewpoint of achieving both the dispersion stability of the mixed solution and the aggregation property of the resin particles.
From the same viewpoint, the temperature in the system in the coagulation step is not less than “softening point of resin constituting the core−75 ° C.” (temperature lower than the softening point by 75 ° C., the same shall apply hereinafter) and the softening point of the resin constituting the core. The following is preferable.

  In addition, additives such as a colorant and a charge control agent may be mixed in advance with the resin containing the amorphous polyester (a) when preparing the resin particles, and each additive is separately added in a dispersion medium such as water. A dispersion liquid dispersed in the mixture may be prepared, mixed with resin particles containing amorphous polyester (a) and other resin particles, and subjected to an aggregation step. When the additive is mixed in advance with the resin containing the amorphous polyester (a) when preparing the resin particles, it is preferable to melt-knead the resin containing the amorphous polyester (a) and the additive in advance. .

[Volume Median Particle Size of Resin Particle I]
The volume median particle size of the resin particles I obtained in Step 1 is preferably 1 to 10 μm, more preferably 2 to 8 μm, and more preferably 3 to 7 μm from the viewpoint of uniformly uniting in the subsequent Step 3 to produce toner particles. Is more preferable.

[Step 2]
Step 2 is a step of obtaining a resin aqueous dispersion containing the amorphous polyester (b). The method for obtaining the aqueous dispersion and preferred physical properties are the same as in Step 1 above. The volume median particle size of the resin aqueous dispersion containing the amorphous polyester (b) to be mixed is preferably 50 to 1,000 nm, more preferably 50 to 500 nm, from the viewpoint of producing uniform core-shell particles. 400 nm is still more preferable, and 100-350 nm is still more preferable.

[Step 3]
In step 3, the aqueous dispersion of resin particles I obtained in step 1 and the aqueous resin dispersion containing the amorphous polyester (b) obtained in step 2 are mixed and agglomerated and coated to form resin particles II. This is a step of obtaining an aqueous dispersion.
The amorphous polyester (b) to be mixed is preferably 5 to 200 parts by weight, more preferably 10 to 100 parts by weight, and still more preferably 100 parts by weight of the resin particles I obtained in Step 1. It is 25-60 mass parts.
The mass ratio of the amorphous polyester (a) and the amorphous polyester (b) in the resin particles I obtained in the step 1 is the same as the amorphous polyester (a) and the amorphous polyester ( It is as the mass ratio with b).
The average particle size of the resin particles II obtained in step 3 is preferably 1-10 μm in volume median particle size, more preferably 2-8 μm, from the viewpoint of uniformly uniting in the subsequent step 4 to produce toner particles. 3 to 7 μm is more preferable. Aggregation conditions are the same as in Step 1 described above.

[Step 4]
Step 4 is a step of uniting the resin particles II obtained in Step 3. That is, after adding an aggregation terminator as necessary to the aqueous dispersion of aggregated particles II obtained in Step 3, the aggregated particles II in the aqueous dispersion are coalesced by being subjected to a coalescence step. This is a step of obtaining an aqueous dispersion of coalesced particles.
In step 4, the aggregated particles obtained in step 3 can be united by heating.
Here, coalescence includes amorphous polyester (b) in which a plurality of resin particles I existing on the inner side of aggregated particles II are fused together to form a core, and aggregated particles I are aggregated and coated. The resin is fused to form a shell, and the core and the shell are appropriately bonded to form a core-shell structure.
The temperature in the system in the step 4 is not less than “softening point of all resins—55 ° C.” or more and “the softening point + 10 ° C.” from the viewpoints of target particle size, particle size distribution, shape control and particle fusing property. Or less, more preferably “the softening point−50 ° C.” or more and “the softening point + 10 ° C.” or less, more preferably “the softening point−45 ° C.” or more and “the softening point + 10 ° C.” or less. Specifically, from the same viewpoint, it is preferably maintained at 40 to 90 ° C, more preferably 50 to 80 ° C. The stirring speed is preferably a speed at which the aggregated particles do not settle.
When an aggregation stopper is used, a surfactant is preferably used as the aggregation stopper, and an anionic surfactant is more preferably used from the viewpoints of availability and operability. Of the anionic surfactants, it is more preferable to use at least one selected from the group consisting of alkyl ether sulfates, alkyl sulfates, and linear alkylbenzene sulfonates.

〔Post-process〕
By appropriately subjecting the coalesced particles obtained in the step 4 to a solid-liquid separation step such as filtration, a washing step, and a drying step, the electrostatic image developing toner of the present invention can be obtained.
In the washing step, it is preferable to completely remove the added nonionic surfactant by washing, and washing with an aqueous solution below the cloud point of the nonionic surfactant is preferred. The washing is preferably performed a plurality of times.
In the drying step, any method such as a vibration type fluidized drying method, a spray drying method, a freeze drying method, a flash jet method, or the like can be employed. The water content after drying of the toner is preferably adjusted to 1.5% by mass or less, more preferably 1.0% by mass or less, from the viewpoint of chargeability.

Further, an external additive may be added for the purpose of improving fluidity. Examples of the external additive include silica fine particles whose surface is hydrophobized, titanium oxide fine particles, alumina fine particles, cerium oxide fine particles, and inorganic fine particles such as carbon black; polymer fine particles such as polycarbonate, polymethyl methacrylate, and silicone resin, and the like. Fine particles can be used.
The number average particle diameter of the external additive is preferably 4 to 200 nm, more preferably 8 to 30 nm, from the viewpoint of the fluidity of the toner.

  In the case of adding an external additive, the amount of the additive added is 0.1% relative to 100 parts by mass of the toner before the processing with the external additive, from the viewpoint of the fluidity of the toner, the environmental stability of the charging degree, and the weighted storage stability. 1-5 mass parts is preferable, 0.1-1 mass part is more preferable, 0.2-0.8 mass part is still more preferable.

[Physical properties of toner for developing electrostatic image]
The volume-median particle size of the toner for developing an electrostatic charge image of the present invention is preferably 1 to 10 μm, more preferably 2 to 8 μm, and still more preferably 3 to 7 μm, from the viewpoint of high image quality and productivity of the toner.
Further, the softening point of the toner is preferably 80 to 160 ° C., more preferably 80 to 150 ° C., and still more preferably 90 to 140 ° C. from the viewpoints of low-temperature fixability, heat-resistant storage stability, and charging stability of the toner.
The electrostatic image developing toner of the present invention can be used as a one-component developer or as a two-component developer mixed with a carrier.

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

<1> A toner for developing an electrostatic charge image having a core and a shell, wherein the core is composed of an alcohol component containing an aliphatic diol and an acid component containing 5 mol% or more and 50 mol% or less of alkenyl succinic acid. The amorphous polyester (a) having a softening point of 75 ° C. or higher and 105 ° C. or lower obtained by polymerization is included, and the shell includes an alcohol component containing an aromatic diol and an acid component containing an aromatic carboxylic acid. Containing amorphous polyester (b) obtained by condensation polymerization, the content of aliphatic diol and aliphatic carboxylic acid in all monomers constituting the core polyester is 55 mol% or more, and constitutes the shell polyester A toner for developing an electrostatic charge image, wherein the content of aromatic diol and aromatic carboxylic acid in all monomers is 80 mol% or more.

<2> The alkylene oxide adduct of bisphenol A in the alcohol component of the amorphous polyester (b) is 60 mol% or more, preferably 80 to 100 mol%, more preferably 90 to 100 mol%, still more preferably 95 to The toner for developing an electrostatic charge image according to <1>, containing 100 mol%.
<3> The aliphatic diol having 2 to 6 carbon atoms in the alcohol component of the amorphous polyester (a) is 80 mol% or more, preferably 80 to 100 mol%, more preferably 90 to 100 mol%, still more preferably. The toner for developing an electrostatic charge image according to <1> or <2>, containing 95 to 100 mol%.
<4> The electrostatic image developing toner according to <3>, wherein the aliphatic diol having 2 to 6 carbon atoms has one or more secondary hydroxyl groups.
<5> The toner for developing an electrostatic charge image according to any one of <1> to <4>, wherein the softening point of the polyester of the shell is higher than the softening point of the polyester of the core.

<6> The softening point of the polyester of the shell is higher than the softening point of the polyester of the core, and the difference between these softening points is preferably 2 ° C. or higher, more preferably 5 ° C. or higher, and still more preferably 20 ° C. or higher. More preferably, it is 25 degreeC or more, Preferably it is 40 degrees C or less, More preferably, it is 30 degrees C or less, Preferably it is 2-40 degreeC, More preferably, it is 5-40 degreeC, More preferably, it is 20-40 degreeC, The electrostatic image developing toner according to any one of <1> to <5>, more preferably 25 to 30 ° C.
<7> The softening point of the amorphous polyester (b) is higher than the softening point of the amorphous polyester (a), and the difference between these softening points is preferably 2 ° C or higher, more preferably 5 ° C or higher, and still more preferably. Is 20 ° C. or higher, more preferably 25 ° C. or higher, and preferably 40 ° C. or lower, more preferably 30 ° C. or lower, preferably 2 to 40 ° C., more preferably 5 to 40 ° C. The toner for developing an electrostatic charge image according to any one of <1> to <6>, preferably 20 to 40 ° C, more preferably 25 to 30 ° C.
<8> The glass transition temperature of the amorphous polyester (b) is preferably 45 ° C. or higher, more preferably 60 ° C. or higher, still more preferably 65 ° C. or higher, and preferably 75 ° C. or lower, preferably The electrostatic image developing toner according to any one of <1> to <7>, which is 45 to 75 ° C, more preferably 60 to 75 ° C, still more preferably 65 to 75 ° C.
<9> The content of the aromatic carboxylic acid in the acid component of the amorphous polyester (b) is 60 mol% or more, more preferably 70 to 100 mol%, still more preferably 90 to 100 mol%, The toner for developing an electrostatic charge image according to any one of <1> to <8>, further preferably 95 to 100 mol%.
<10> The mass ratio of the polyester of the core and the polyester of the shell is 100/20 to 100/70, preferably 100/20 to 100/70, more preferably 100/20 to 100/50, The toner for developing an electrostatic charge image according to any one of <1> to <9>, further preferably 100/20 to 100/40.

<11> In the alcohol component of the amorphous polyester (a), an aliphatic diol having 3 to 4 carbon atoms and having one or more secondary hydroxyl groups is 80 mol% or more, preferably 80 to 100 mol%, The toner for developing an electrostatic charge image according to any one of <1> to <10>, more preferably 90 to 100 mol%, and still more preferably 95 to 100 mol%.
<12> The alcohol component of the amorphous polyester (a) contains one or more selected from 2,3-butanediol, 1,2-propanediol, neopentyl glycol, and ethylene glycol, The alcohol component of the amorphous polyester (b), wherein the acid component of the crystalline polyester (a) includes one or more selected from alkenyl succinic acid, derivatives and anhydrides thereof, terephthalic acid, and isophthalic acid Any of <1> to <11>, wherein the component includes an alkylene oxide adduct of bisphenol A, and the acid component of the amorphous polyester (b) includes one or two selected from terephthalic acid and isophthalic acid The electrostatic image developing toner according to claim 1.
<13> The electrostatic image developing toner according to <12>, wherein the acid component of the amorphous polyester (a) further contains trimellitic acid.
<14> The toner for developing an electrostatic charge image according to <12> or <13>, wherein the acid component of the amorphous polyester (b) further contains trimellitic acid.
<15> The number average molecular weight of the amorphous polyester (a) is preferably 1,000 to 5,000, more preferably 2,000 to 4,000, and still more preferably 3,000 to 3,500. The weight average molecular weight is 6,000 to 30,000, more preferably 9,000 to 20,000, still more preferably 10,000 to 15,000, according to any one of <1> to <14>. Toner for developing electrostatic images.

<16> The number average molecular weight of the amorphous polyester (b) is preferably 1,000 to 5,000, more preferably 3,000 to 3,500, and the weight average molecular weight is 8,000 to 30,000. The toner for developing an electrostatic charge image according to any one of <1> to <15>, which is 000, more preferably 12,000 to 20,000.
<17> The softening point of the amorphous polyester (a) is 75 ° C. or higher and 105 ° C. or lower, preferably 80 ° C. or higher, more preferably 90 ° C. or higher, and preferably 105 ° C. or lower, more preferably The electrostatic image developing toner according to any one of <1> to <16>, which is 100 ° C. or lower, preferably 80 to 105 ° C., and more preferably 90 to 100 ° C.
<18> The softening point of the amorphous polyester (b) is preferably 100 ° C. or higher, more preferably 105 ° C. or higher, still more preferably 120 ° C. or higher, and preferably 140 ° C. or lower, more preferably 135 ° C. Hereinafter, more preferably 130 ° C. or less, preferably 100 to 140 ° C., more preferably 105 to 135 ° C., and further preferably 120 to 130 ° C., according to any one of <1> to <17> Toner for developing electrostatic images.
<19> The glass transition temperature of the polyester constituting the core is preferably 30 ° C. or higher, more preferably 35 ° C. or higher, preferably 60 ° C. or lower, more preferably 50 ° C. or lower, still more preferably 45 ° C. or lower. The toner for developing an electrostatic charge image according to any one of <1> to <18>, which is preferably 30 to 60 ° C, more preferably 35 to 50 ° C, and still more preferably 35 to 45 ° C.
The glass transition temperature of the polyester constituting the <20> shell is preferably 45 ° C. or higher, more preferably 60 ° C. or higher, still more preferably 65 ° C. or higher, and preferably 75 ° C. or lower, preferably 45 to 45 ° C. The electrostatic image developing toner according to any one of <1> to <19>, which is 75 ° C, more preferably 60 to 75 ° C, and still more preferably 65 to 75 ° C.

The glass transition temperature of the polyester constituting the <21> shell is preferably 45 ° C. or higher, more preferably 60 ° C. or higher, still more preferably 65 ° C. or higher, and preferably 75 ° C. or lower, preferably 45 to 45 ° C. The toner for developing an electrostatic charge image according to any one of <1> to <20>, which is 75 ° C., more preferably 60 to 75 ° C., and still more preferably 65 to 75 ° C.
<22> The glass transition temperature of the amorphous polyester (a) is preferably 30 ° C. or higher, more preferably 35 ° C. or higher, preferably 60 ° C. or lower, more preferably 50 ° C. or lower, still more preferably 45. The toner for developing an electrostatic charge image according to any one of <1> to <21>, which is not higher than ° C, preferably 30 to 60 ° C, more preferably 35 to 50 ° C, and still more preferably 35 to 45 ° C.
<23> The glass transition temperature of the amorphous polyester (a) is preferably 30 ° C. or higher, more preferably 35 ° C. or higher, preferably 60 ° C. or lower, more preferably 50 ° C. or lower, still more preferably 45. The toner for developing an electrostatic charge image according to any one of <1> to <22>, which is not higher than ° C, preferably 30 to 60 ° C, more preferably 35 to 50 ° C, and still more preferably 35 to 45 ° C.
<24> The acid values of the amorphous polyester (a) and the amorphous polyester (b) are each independently preferably 10 to 40 mgKOH / g, more preferably 15 to 30 mgKOH / g, and even more preferably 15 The toner for developing an electrostatic charge image according to any one of <1> to <23>, which is -28 mgKOH / g.
<25> The acid values of the amorphous polyester (a) and the amorphous polyester (b) are each independently preferably 10 to 40 mgKOH / g, more preferably 15 to 30 mgKOH / g, and even more preferably 15 The toner for developing an electrostatic charge image according to any one of <1> to <24>, which is -28 mgKOH / g.

The content of <26> amorphous polyester (a) in the resin constituting the core is preferably 50% by mass or more, more preferably 70% by mass or more, still more preferably 80% by mass or more, and still more preferably 90%. The toner for developing an electrostatic charge image according to any one of <1> to <25>, wherein the toner is at least% by mass, more preferably substantially 100% by mass.
<27> The content of the amorphous polyester (b) in the resin constituting the shell is 50% by mass or more, preferably 70% by mass or more, more preferably 80% by mass or more, and further preferably 90% by mass or more. More preferably, the toner for developing an electrostatic charge image according to any one of <1> to <26>, which is substantially 100% by mass.
<28> The mass ratio (a) / (b) of the amorphous polyester (a) to the amorphous polyester (b) is 100/10 to 100/70, preferably 100/20 to 100/70, more preferably. Is a toner for developing an electrostatic charge image according to any one of <1> to <27>, which is 100/20 to 100/50.
<29> The method for producing a toner for developing an electrostatic charge image according to any one of <1> to <28>, comprising the following steps 1 to 4.
Step 1: Step of obtaining an aqueous dispersion of resin particles I containing amorphous polyester (a) Step 2: Step of obtaining an aqueous resin dispersion containing amorphous polyester (b) Step 3: Obtained in Step 1 A step of mixing an aqueous dispersion of resin particles I and a resin aqueous dispersion containing the amorphous polyester (b) obtained in step 2 to obtain an aqueous dispersion of resin particles II Step 4: Step 3 The step <30> of combining the resin particles II obtained in step <30> is a step of aggregating the resin aqueous dispersion containing the amorphous polyester (a) to obtain an aqueous dispersion of the resin particles I. <29> The method for producing a toner for developing an electrostatic charge image according to <29>.

<31> In step 1, by mixing amorphous polyester (a), an organic solvent and water, and if necessary, a neutralizing agent and a surfactant, stirring, and then removing the organic solvent by distillation or the like. The method for producing a toner for developing an electrostatic charge image according to <30>, wherein an aqueous resin dispersion containing an amorphous polyester (a) is obtained.
<32> In the aqueous dispersion in Step 1, the medium in which the resin is dispersed is preferably 50% by mass or more, more preferably 70% by mass or more, still more preferably 90% by mass or more, and even more preferably 99% by mass or more. The method for producing a toner for developing an electrostatic charge image according to any one of <29> to <31>, further preferably 100% by mass.
<33> In step 2, the volume median particle size of the resin particles in the resin aqueous dispersion containing the amorphous polyester (b) is 50 to 1,000 nm, preferably 50 to 500 nm, more preferably 50 to 400 nm. More preferably, the method for producing a toner for developing an electrostatic charge image according to any one of <29> to <32>, wherein an aqueous resin dispersion containing an amorphous polyester (b) is obtained so as to have a thickness of 100 to 350 nm. .
<34> In step 3, the amorphous polyester (b) is preferably 5 to 200 parts by mass, more preferably 10 to 100 parts by mass with respect to 100 parts by mass of the resin particles I obtained in step 1. More preferably, the aqueous dispersion of the resin particles I obtained in step 1 and the aqueous resin dispersion containing the amorphous polyester (b) obtained in step 2 are mixed so that the amount is 25 to 60 parts by mass. The method for producing a toner for developing an electrostatic charge image according to any one of <29> to <33>, wherein the toner is agglomerated to obtain an aqueous dispersion of resin particles II.
<35> In step 3, the resin particles II having an average particle diameter of 1 to 10 μm, preferably 2 to 8 μm, more preferably 3 to 7 μm in volume median particle diameter are obtained. <29> to <34> A method for producing a toner for developing an electrostatic image according to any one of the above.

<36> The temperature in the system in step 4 is not less than “softening point of all resins−55 ° C.” and not more than “the softening point + 10 ° C.”, preferably not less than “the softening point−50 ° C.” and “the softening point + 10”. <29 ° C.> <35>, more preferably “the softening point −45 ° C.” or more and “the softening point + 10 ° C.” or less, preferably 40 to 90 ° C., more preferably 50 to 80 ° C. A method for producing a toner for developing an electrostatic image according to any one of the above.

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

[Acid value of polyester]
The acid value of the polyester was measured based on the method of JIS K 0070. However, only the measurement solvent was changed from the mixed solvent of ethanol and ether specified in JIS K 0070 to a mixed solvent of acetone and toluene (acetone: toluene = 1: 1 (volume ratio)).

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

(2) Endothermic maximum peak temperature, melting point Using a differential scanning calorimeter (trade name: “Q-100”, manufactured by TA Instruments Japan Co., Ltd.), the temperature decreasing rate from room temperature (20 ° C.) to 10 ° C. The sample cooled to 0 ° C. at a rate of 1 minute was allowed to stand still for 1 minute, and then measured while the temperature was raised to 180 ° C. at a rate of temperature increase of 10 ° C./minute. Among the observed endothermic peaks, the temperature of the peak on the highest temperature side was defined as the maximum endothermic peak temperature and used for calculation of the crystallinity index. In the case of crystalline polyester, the maximum peak temperature was taken as the melting point.

(3) Glass transition temperature Using a differential scanning calorimeter (trade name: “Q-100” manufactured by TA Instruments Japan Co., Ltd.), 0.01 to 0.02 g of sample is weighed in an aluminum pan. The temperature was raised to 200 ° C., and the temperature was cooled to 0 ° C. at a temperature lowering rate of 10 ° C./min. Next, the measurement was performed while increasing the temperature to 150 ° C. at a temperature increase rate of 10 ° C./min. The glass transition temperature was defined as the temperature at the intersection of the base line extension below the maximum peak temperature of endotherm and the tangent indicating the maximum slope from the peak rising portion to the peak apex.

[Number average molecular weight and weight average molecular weight of polyester]
By the following method, the molecular weight distribution was measured by gel permeation chromatography (GPC) method, and the number average molecular weight M _n and the weight average molecular weight M _w of the resin were determined.
(1) Preparation of sample solution The resin was dissolved in chloroform so that the concentration was 0.5 g / 100 mL. Subsequently, this solution was filtered using a fluororesin filter having a pore size of 2 μm (manufactured by Sumitomo Electric Industries, Ltd., trade name: FP-200) to remove insoluble components to obtain a sample solution.
(2) Molecular weight measurement Using the following apparatus, chloroform was flowed as an eluent at a flow rate of 1 ml per minute, and the column was stabilized in a constant temperature bath at 40 ° C. Measurement was performed by injecting 100 μl of the sample solution. The molecular weight of the sample was calculated based on a calibration curve prepared in advance. The calibration curve at this time includes several types of monodisperse polystyrene (monodisperse polystyrene manufactured by Tosoh Corporation; 2.63 × 10 ³ , 2.06 × 10 ⁴ , 1.02 × 10 ⁵ , GL Sciences Inc.) Monodispersed polystyrenes made from 2.10 × 10 ³ , 7.00 × 10 ³ , 5.04 × 10 ⁴ (number average molecular weight)) were used as standard samples.
Measuring device: CO-8010 (trade name, manufactured by Tosoh Corporation)
Analytical column: GMH _XL + G3000H _XL (both trade names, manufactured by Tosoh Corporation)

[Volume Median Particle Size (D ₅₀ ) 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)
-Dispersion: Polyoxyethylene lauryl ether (trade name, Emulgen 109P, HLB: 13.6, manufactured by Kao Corporation) was dissolved in the electrolytic solution to obtain a dispersion having a concentration of 5% by mass.
-Dispersion condition: 10 mg of a toner measurement sample is added to 5 mL of the dispersion, and dispersed for 1 minute with an ultrasonic disperser, and then 25 mL of electrolyte is added, and further dispersed for 1 minute with an ultrasonic disperser. A sample dispersion was prepared.
Measurement conditions: The sample dispersion is added to 100 mL of the electrolytic solution to adjust the particle size of 30,000 particles to a concentration that can be measured in 20 seconds, and then 30,000 particles are measured and the particle size distribution thereof. The volume-median particle size (D ₅₀ ) and the number percent of the particle size of 2 μm or less were determined.
The CV value (%) was calculated according to the following formula.
CV value (%) = (standard deviation of particle size distribution / volume median particle size (D ₅₀ )) × 100

[Volume Median Particle Size (D ₅₀ ) of Toner and Toner Particles]
The volume median particle size of the toner and 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 mass.
-Dispersion condition: 10 mg of a toner measurement sample is added to 5 mL of the dispersion, and dispersed for 1 minute with an ultrasonic disperser, and then 25 mL of electrolyte is added, and further dispersed for 1 minute with an ultrasonic disperser. A sample dispersion was prepared.
Measurement conditions: The sample dispersion is added to 100 mL of the electrolytic solution to adjust the particle size of 30,000 particles to a concentration that can be measured in 20 seconds, and then 30,000 particles are measured and the particle size distribution thereof. From this, the volume median particle size (D ₅₀ ) was determined.

[Volume Median Particle Size (D ₅₀ ) of Resin Particles, Colorant, Release Agent Particle, Charge Control Agent]
(1) Measuring device: Laser diffraction particle size measuring machine (Horiba, Ltd., trade name: LA-920)
(2) Measurement conditions: Distilled water was added to the measurement cell, and the volume-median particle size (D ₅₀ ) was measured at a concentration at which the absorbance was in an appropriate range.

[Low-temperature fixability of toner]
A toner was mounted on a copier “AR-505” (trade name, manufactured by Sharp Corporation), and a solid image was taken out before passing through the fixing machine to obtain an unfixed image (printing area: 2 cm × 12 cm, adhesion amount: 0.5 mg / cm ² ). Further, an unfixed image was printed twice on the same paper to obtain a layer thickness of 1.5 mg / cm ² .
The fixing machine of the copying machine was fixed on paper at 300 mm / sec while increasing the fixing temperature sequentially from 90 ° C. to 240 ° C. in 5 ° C. increments. As the fixing paper, “CopyBond SF-70NA” (trade name, manufactured by Sharp Corporation, 75 g / m ² ) was used.
A sand eraser with a bottom surface of 15 mm x 7.5 mm under a load of 500 g. The image fixed through the fixing machine is rubbed 5 times, and the optical reflection density before and after rubbing is measured by a reflection densitometer “RD-915” (trade name) The temperature of the fixing roller in which the ratio between the two (after rubbing / before rubbing) first exceeded 80% was defined as the minimum fixing temperature. A lower minimum fixing temperature is preferable.

[Heat resistant storage stability of toner]
10 g of toner was placed in a 50 ml polycup and held for 24 hours in an environment of 55 ° C. and 60% RH. After that, on a powder tester (manufactured by Hosokawa Micron Co., Ltd.), in order from the top, three sieves of sieve A (aperture 250 μm), sieve B (aperture 150 μm), and sieve C (aperture 75 μm) are stacked and installed. A toner (10 g) was placed on A and vibrated for 60 seconds. The fluidity was evaluated using the value (α) calculated from the following equation. Larger numbers are preferable.

  α = [100-[(Mass of toner remaining on sieve A (g)) + (Mass of toner remaining on sieve B (g)) × 0.6 + (Mass of toner remaining on sieve C (g)) × 0.2] / 10 (g) × 100

[Toner durability]
The toner is mounted on a printing machine “Page Presto N-4” (Casio Computer Co., Ltd., fixing: contact fixing method, developing: non-magnetic one-component developing method, developing roll diameter: 2.3 cm), and the temperature is 32 ° C. An oblique stripe pattern with a blackening rate of 5.5% was continuously printed in an environment of 85% humidity. On the way, a black solid image was printed every 500 sheets, and the presence or absence of streaks on the image was confirmed. Printing was stopped when streaks occurred on the image, and printing was performed up to 9000 sheets. The number of prints until the time when the streaks were visually observed on the image was defined as the number of streaks due to the fusion and fixing of the toner on the developing roll, and the durability was evaluated. In other words, it can be determined that the greater the number of sheets where no streaking occurs, the higher the durability of the toner.

Production Example 1
(Production of alkylene compound A)
Using propylene tetramer (trade name: “Light Tetramer” manufactured by Nippon Oil Corporation), fractionation was carried out under heating conditions of 183 to 208 ° C. to obtain alkylene compound A. The obtained alkylene compound A had 40 peaks in gas chromatography mass spectrometry described later. The distribution of the alkylene compound was as follows: C ₉ H ₁₈ : 0.5 wt%, C ₁₀ H ₂₀ : 4 wt%, C ₁₁ H ₂₂ : 20 wt%, C ₁₂ H ₂₄ : 66 wt%, C ₁₃ H ₂₆ : 9 % By weight and C ₁₄ H ₂₈ : 0.5% by weight.

[Analysis of Alkylene Compound A by Mass Spectrometry Gas Chromatography]
A CI ion source and the following analytical column were attached to a mass spectrometric gas chromatograph (GC / MS) and started up. In addition, CI reaction gas (methane) was flowed, and tuning was performed 24 hours after the evacuation work of the MS part.

(1) GC
Gas chromatograph:
Product name: “HP6890N”, manufactured by Agilent
Analytical column:
Ultra 1 manufactured by HP (trade name, column length 50 m, inner diameter 0.2 mm, film thickness 0.33 μm)
GC oven temperature rising condition:
Initial temperature 100 ° C (0 minutes)
First stage heating rate 1 ° C / min (up to 150 ° C)
Second stage heating rate 10 ° C / min (up to 300 ° C)
Final temperature 300 ° C (10 minutes)
Sample injection volume: 1 μL
Inlet conditions:
Injection mode Split method Split ratio 50: 1
Inlet temperature 300 ° C
Carrier gas:
Gas helium flow rate 1ml / min (constant flow mode)

(2) Detector mass spectrometer: manufactured by Agilent, trade name: “5973N MSD”
Ionization method: Chemical ionization method Reaction gas: Isobutane temperature setting:
Quadrupole 150 ° C
Ion source 250 ℃
Detection condition: Scan scan range: m / z 75-300
Detector ON time: 5 minutes Calibration (mass calibration and sensitivity adjustment):
Reaction gas Methane calibrant PFDTD (Perfluoro-5,8-dimethyl-3,6,9-trioxidedecane)
Tuning method Auto tuning

(3) Sample preparation Propylene tetramer was prepared by dissolving in isopropyl alcohol at a concentration of 5% by weight.

(Data processing method)
For the alkene component of each carbon number in the range of 9 to 14 carbon atoms, a mass chromatogram with a mass number corresponding to each molecular ion is extracted, and under the condition of S / N (signal / noise ratio)> 3, Integration was performed according to the integration conditions for each component shown in Tables 2-5. From the detection results shown in Table 1, the ratio of the specific alkyl chain length component was calculated by the following formula.

(4) Integration condition component: C ₉ H ₁₈

Ingredient: C ₁₀ H ₂₀

Ingredients: C ₁₁ H ₂₂ , C ₁₂ H ₂₄ and C ₁₃ H ₂₆

Ingredients: C ₁₄ H ₂₈

  In the present invention, an alkylene compound having 9 to 14 carbon atoms refers to a peak corresponding to a molecular ion in gas chromatography mass spectrometry.

Production Example 2
(Production of alkenyl succinic anhydride A)
1 L autoclave manufactured by Nitto Koatsu Co., Ltd. 542.4 g of alkylene compound A, 157.2 g of maleic anhydride, 0.4 g of antioxidant Chelex-O (manufactured by SC Organic Chemical Co., Ltd., Triisooctyl phosphite), butyl as a polymerization inhibitor Hydroquinone (0.1 g) was charged and pressurized nitrogen substitution (0.2 MPaG) was repeated three times. After stirring was started at 60 ° C., the temperature was raised to 230 ° C. over 1 hour and the reaction was performed for 6 hours. The pressure when the reaction temperature was reached was 0.3 MPaG. After completion of the reaction, the reaction mixture was cooled to 80 ° C., returned to normal pressure (101.3 kPa), and transferred to a 1 L four-necked flask. The temperature was raised while stirring to 180 ° C., and the remaining alkylene compound was distilled off at 1.3 kPa over 1 hour. Subsequently, after cooling to room temperature (25 ° C.), the pressure was returned to normal pressure (101.3 kPa) to obtain 406.1 g of the target alkenyl succinic anhydride A. The average molecular weight of alkenyl succinic anhydride A determined from the acid value was 268.

[Production of amorphous polyester]
Production Examples 3-6, 8 and 9
(Production of amorphous polyesters A1 to A4, A6, A7)
A dehydration tube equipped with a fractionation tube through which an alcohol component and an acid component, esterification catalyst and gallic acid, which are raw materials of polyester other than trimellitic anhydride shown in Table 6, were passed through a nitrogen introduction tube and hot water at 100 ° C, Place in a 5 liter four-necked flask equipped with a stirrer and a thermocouple, keep the temperature at 180 ° C. for 1 hour under a nitrogen atmosphere, then increase the temperature from 180 ° C. to 230 ° C. at 10 ° C./hour, then at 230 ° C. The polycondensation reaction was carried out for 10 hours, and the reaction was further carried out at 230 ° C. and 8.0 kPa for 1 hour. Next, the temperature was lowered to 210 ° C., trimellitic anhydride was added, and the reaction was carried out at 210 ° C. and 10 kPa to the softening point shown in Table 6 to obtain amorphous polyesters A1 to A4, 6 and 7. The physical properties are shown in Table 6.

Production Examples 7, 10, 12, 13
(Production of amorphous polyester A5, B1, B3, B4)
Four 5-liter capacity equipped with nitrogen introduction tube, dehydration tube, stirrer and thermocouple for alcohol component and acid component, esterification catalyst and gallic acid as raw materials of polyester other than trimellitic anhydride shown in Table 6 The flask was placed in a neck flask and subjected to a condensation polymerization reaction at 230 ° C. for 10 hours in a nitrogen atmosphere, and further reacted at 230 ° C. and 8.0 kPa for 1 hour. Next, the temperature was lowered to 210 ° C., trimellitic anhydride was added, and the reaction was performed at 210 ° C. and 10 kPa to the softening point shown in Table 6 to obtain amorphous polyesters A5, B1, B3, and B4. The physical properties are shown in Table 6.

Production Example 11
(Production of amorphous polyester B2)
A 5-liter volume equipped with a nitrogen introduction tube, a dehydration tube, a stirrer, and a thermocouple containing alcohol components and acid components, esterification catalyst and gallic acid as raw materials for polyesters other than trimellitic anhydride and fumaric acid shown in Table 6 Were subjected to a condensation polymerization reaction at 230 ° C. for 10 hours in a nitrogen atmosphere, and further reacted at 230 ° C. and 8.0 kPa for 1 hour. After cooling to 180 ° C., trimellitic anhydride, fumaric acid, and 4-tert-butylcatechol which is a polymerization inhibitor were added, and the temperature was raised from 180 ° C. to 210 ° C. at 10 ° C./hour. The reaction was performed for a time, and the reaction was further performed at 210 ° C. and 10 kPa until the softening point shown in Table 6 was reached, to obtain amorphous polyester B2. The physical properties are shown in Table 6.

Production Example 14
(Production of crystalline polyester c1)
Four 5-liter liters equipped with a nitrogen introduction tube, a dehydration tube, a stirrer, and a thermocouple were prepared by using an alcohol component and an acid component as raw materials for the polyester shown in Table 6 and 4-tert-butylcatechol as a polymerization inhibitor. After putting in a neck flask and reacting at 140 ° C. for 5 hours, the reaction was carried out while increasing the temperature up to 200 ° C. at 10 ° C./hour. After reacting to a reaction rate of 80% at 200 ° C., the esterification catalyst shown in Table 6 was added, and the reaction was further carried out at 200 ° C. for 2 hours. Furthermore, reaction was performed at 8 kPa for 2 hours to obtain crystalline polyester c1.

[Production of resin particles]
Production Examples 15 to 26
(Production of resin particle dispersions A1 to A7, c1 and B1 to B4)
Into a 5 L container equipped with a stirrer, reflux condenser, dropping funnel, thermometer and nitrogen introduction tube, 600 g of methyl ethyl ketone was charged, and 200 g of amorphous polyester or crystalline polyester produced in Production Examples 1 to 12 was added at 60 ° C. And dissolved. 4 g of sodium hydroxide was added to each of the obtained solutions for neutralization, followed by addition of 2000 g of ion-exchanged water, and then methyl ethyl ketone was distilled at a temperature of 50 ° C. or lower under reduced pressure at a stirring rate of 250 r / min. And ion-exchanged water was added to adjust the solid content to 9.6% by mass to obtain resin particle dispersions A1 to A7, c1 and B1 to B4. The results are shown in Table 7.

[Production of colorant dispersion]
Production Example 27
50 g of copper phthalocyanine (manufactured by Dainichi Seika Kogyo Co., Ltd., model number: “ECB-301”), 5 g of nonionic surfactant (trade name: “Emulgen 150”, manufactured by Kao Corporation) and 200 g of ion-exchanged water are mixed. The mixture was dispersed at 25 ° C. for 10 minutes using a homogenizer to obtain a colorant dispersion. The volume median particle size was 120 nm.

[Production of release agent particle dispersion]
Production Example 28
Paraffin wax (manufactured by Nippon Seiwa Co., Ltd., trade name: “HNP0190”, melting point: 85 ° C.) 50 g, cationic surfactant (trade name: “Sanisol B50” manufactured by Kao Corporation) and ion-exchanged water 200 g was heated to 95 ° C., and paraffin wax was dispersed using a homogenizer, followed by dispersion treatment using a pressure discharge homogenizer to obtain a release agent particle dispersion. The volume median particle size of the release agent particles was 550 nm.

[Production of charge control agent dispersion]
Production Example 29
50 g of charge control agent (Orient Chemical Co., Ltd., salicylic acid compound, trade name: “Bontron E-84”), 5 g of nonionic surfactant (trade name: “Emulgen 150”, manufactured by Kao Corporation) and 200 g of ion-exchanged water was mixed, and glass beads were used at 25 ° C. and dispersed for 10 minutes using a sand grinder to obtain a charge control agent dispersion. The volume median particle size of the charge control agent was 500 nm.

[Production of toner]
Example 1
As resin particle dispersion for core, 500 g of resin particle dispersion A1, 20 g of colorant dispersion, 5 g of release agent dispersion, 4 g of charge control agent dispersion, and cationic surfactant (trade name, manufactured by Kao Corporation) : "Sanisol B50") 1.5 g was mixed and dispersed in a round stainless steel flask using a homogenizer, and then heated to 48 ° C while stirring the inside of the flask in a heating oil bath. Furthermore, it hold | maintained at 48 degreeC for 1 hour, and the aggregated particle was formed. The volume median particle size of the aggregated particles at this time was 5.1 μm. Thereafter, 150 g of resin particle dispersion B1 was added as a resin particle dispersion for the shell, and the mixture was stirred and dispersed to obtain core-shell aggregated particles. At this time, the volume median particle size of the aggregated particles was 5.3 μm.
After adding 3 g of an anionic surfactant (trade name: “Perex SS-L”, manufactured by Kao Corporation) to the core-shell aggregated particle dispersion, a reflux tube was attached to the stainless steel flask and stirring was continued. While heating to 75 ° C. at a rate of 0.1 ° C./min and holding for 2 hours, the aggregated particles were coalesced and fused. Thereafter, the mixture was cooled, the fused particles were filtered, sufficiently washed with ion exchange water, and then dried to obtain toner particles. The obtained toner particles had a volume-median particle size (D ₅₀ ) of 5.3 μm.
0.5 parts by mass of external additives (hydrophobic silica, manufactured by Nippon Aerosil Co., Ltd., trade name: “Aerosil R-972”, number average particle size: 16 nm (catalog value)) with respect to 100 parts by mass of toner particles The mixture was added and mixed with a Henschel mixer (Mitsui Mining Co., Ltd.) for 3 minutes at 3600 r / min (peripheral speed 31.7 m / s) to perform external additive treatment, and toner (volume median particle size D ₅₀ = 5 .3 μm). Table 8 shows the physical properties and evaluation of the toner.

Examples 2 to 10 and Comparative Examples 1 to 4
Toner particles were obtained in the same manner as in Example 1 except that the core resin particle dispersion and the shell resin particle dispersion were changed as shown in Table 8.
However, in Example 9, the addition amount of the resin particle dispersion for the shell was 300 g.
In Example 10, 193 g (55 parts by mass) of resin particle dispersion A1 and 107 g (15 parts by mass) of resin particle dispersion c1 were used as the resin particle dispersion for the core.
The volume-median particle size (D ₅₀ ) of the obtained toner particles was 5.3 μm as in the toner particles of Example 1.
Using the obtained toner particles, the same operation as in Example 1 was performed to obtain a toner. Table 8 shows the physical properties and evaluation of the toner.

  From Table 8, it can be seen that the electrostatic image developing toners of the examples are all superior in low-temperature fixability, heat resistant storage stability and durability as compared with the electrostatic image developing toners of the comparative examples.

  The electrostatic image developing toner obtained by the production method of the present invention is excellent in low-temperature fixability, heat-resistant storage stability and durability, and therefore can be suitably used as a toner used in electrophotography. According to the method of the present invention, a toner having such characteristics can be produced efficiently.

Claims (13)

An electrostatic charge image developing toner having a core and a shell,
The core is obtained by polycondensation of an alcohol component containing an aliphatic diol and an acid component containing 5 mol% to 50 mol% of alkenyl succinic acid, and has a softening point of 75 ° C. or higher and 105 ° C. or lower. Including crystalline polyester (a),
The shell includes an amorphous polyester (b) obtained by condensation polymerization of an alcohol component containing an aromatic diol and an acid component containing an aromatic carboxylic acid,
Content of aliphatic diol and aliphatic carboxylic acid in all monomers constituting core polyester is 55 mol% or more, and content of aromatic diol and aromatic carboxylic acid in all monomers constituting shell polyester A toner for developing an electrostatic charge image, having a mol of 80 mol% or more.   2. The electrostatic image developing toner according to claim 1, wherein the alcohol component of the amorphous polyester (b) contains 60 mol% or more of an alkylene oxide adduct of bisphenol A.   The toner for developing electrostatic images according to claim 1, wherein the alcohol component of the amorphous polyester (a) contains an aliphatic diol having 2 to 6 carbon atoms in an amount of 80 mol% or more.   The toner for developing an electrostatic charge image according to claim 3, wherein the aliphatic diol having 2 to 6 carbon atoms has one or more secondary hydroxyl groups.   The toner for developing an electrostatic charge image according to claim 1, wherein the softening point of the polyester of the shell is higher than the softening point of the polyester of the core.   The toner for developing an electrostatic charge image according to any one of claims 1 to 5, wherein the softening point of the polyester of the shell is higher than the softening point of the polyester of the core, and the difference between these softening points is 5 ° C or more and 40 ° C or less.   The softening point of the amorphous polyester (b) is higher than the softening point of the amorphous polyester (a), and the difference between these softening points is 5 ° C or higher and 40 ° C or lower. Toner for developing electrostatic images.   The toner for developing an electrostatic charge image according to claim 1, wherein the amorphous polyester (b) has a glass transition temperature of 60 ° C. or higher and 75 ° C. or lower.   The toner for developing electrostatic images according to claim 1, wherein the content of the aromatic carboxylic acid in the acid component of the amorphous polyester (b) is 60 mol% or more.   The toner for developing an electrostatic charge image according to claim 1, wherein a mass ratio of the polyester of the core and the polyester of the shell is 100/20 to 100/70.   The alcohol component of the amorphous polyester (a) contains at least 80 mol% of an aliphatic diol having 3 to 4 carbon atoms and having one or more secondary hydroxyl groups. The toner for developing an electrostatic image according to the description. The method for producing a toner for developing an electrostatic charge image according to any one of claims 1 to 11, comprising the following steps 1 to 4.
Step 1: Step of obtaining an aqueous dispersion of resin particles I containing amorphous polyester (a) Step 2: Step of obtaining an aqueous resin dispersion containing amorphous polyester (b) Step 3: Obtained in Step 1 A step of mixing an aqueous dispersion of resin particles I and a resin aqueous dispersion containing the amorphous polyester (b) obtained in step 2 to obtain an aqueous dispersion of resin particles II Step 4: Step 3 Step of uniting resin particles II obtained in step 1   13. The method for producing a toner for developing an electrostatic charge image according to claim 12, wherein the step 1 is a step of aggregating the aqueous resin dispersion containing the amorphous polyester (a) to obtain an aqueous dispersion of the resin particles I. .