JP2018059964A - toner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a toner excellent in low temperature fixability, heat resistant storage, and suppression of blurring.SOLUTION: A toner is configured to be a pulverized toner by a melt-kneading method containing a non-crystalline polyester A and a crystalline polyester C which is a polycondensation material with an alcoholic component containing an aliphatic diol having a hydroxyl group joined to a secondary carbon atom in which the non-crystalline polyester A is equal to or more than 3 and less than 5 in the carbon number; and an alcohol component which is a polymerized material with a carboxylic acid component containing an aliphatic dicarboxylic acid group compound. A glass transition point Tg(a)[°C]satisfies the following formula (I), and assuming that a solubility parameter of the non-crystalline polyester A is defined as SP(a)[(cal/cm)], the solubility parameter of the crystalline polyester C is defined as SP(c)[(cal/cm)], and a crystallization temperature is defined as Tc(c)[°C], the flowing formula (II) and the formula (III) are satisfied. Formula(I):50≤Tg(a)≤60, Formula(II):1.10≤SP(a)-SP(c)≤1.50, and Formula(III):5≤Tc(c)-Tg(a)≤17.SELECTED DRAWING: None

Description

  The present invention relates to a toner used for developing a latent image formed in an electrophotographic method, an electrostatic recording method, an electrostatic printing method or the like.

  In recent years, there has been a strong demand for improvements in toner low-temperature fixability from the viewpoint of energy saving, in addition to heat-resistant storage stability and reduction of energy consumption in the fixing process, along with the promotion of miniaturization, high speed and high image quality. ing.

  For example, Patent Document 1 discloses a toner binder having both low-temperature fixability and hot offset resistance and excellent storage stability, and a dicarboxylic acid selected from aromatic dicarboxylic acids and ester-forming derivatives thereof as constituent components. A toner binder containing a polyester resin and a crystalline resin satisfying a specific viscoelastic behavior, containing a tricarboxylic acid or higher polycarboxylic acid and 1,2-propylene glycol is described.

  In Patent Document 2, an alcohol component and a carboxylic acid component are overlapped as a binder resin for a polyester toner that can achieve both low temperature fixability of the obtained toner, storage stability under high temperature and high humidity, and filming resistance. A method for producing a polyester resin binder resin for condensation, wherein the alcohol component contains an aliphatic diol having a hydroxyl group bonded to a secondary carbon atom having 3 to 5 carbon atoms, and is used for polycondensation The molar ratio of alcohol component to carboxylic acid component (alcohol component / carboxylic acid component) is 1.6 to 2.6, the number average molecular weight of the resulting polyester toner binder resin is 4,000 or more, and the softening point is 120 ° C. A method for producing a polyester-based toner binder resin is described below.

JP 2013-228724 A JP 2014-201634 Gazette

From the viewpoint of environmental harmony, the raw material monomer for the binder resin for toner is a short-chain aliphatic derived from a plant such as 1,2-propanediol instead of an aromatic monomer such as an alkylene oxide adduct of bisphenol A. System monomers are attracting attention.
However, although the crystalline polyester resins described in Patent Documents 1 and 2 are difficult to be abnormal at the time of low-speed printing, some of the crystals are not sufficiently formed, and image blurring occurs at the time of high-speed printing. I couldn't say that.

  The present invention relates to a toner excellent in low-temperature fixability, heat-resistant storage stability, and blurring suppression.

The present invention is a pulverized toner by melt-kneading method containing amorphous polyester A and crystalline polyester C,
The amorphous polyester A is a polycondensation of an alcohol component containing an aliphatic diol having a hydroxyl group bonded to a secondary carbon atom having 3 to 5 carbon atoms and a carboxylic acid component containing an aromatic dicarboxylic acid compound. Is a thing,
The crystalline polyester C is a polycondensate of an alcohol component containing an aliphatic diol and a carboxylic acid component containing an aliphatic dicarboxylic acid compound,
The glass transition point Tg (a) [° C.] of the amorphous polyester A satisfies the following formula (I):
The solubility parameter of the amorphous polyester A is SP (a) [(cal / cm ³ ) ^1/2 ], and the solubility parameter of the crystalline polyester C is SP (c) [(cal / cm ³ ) ^1/2 ]. The present invention relates to a toner that satisfies the following formulas (II) and (III) when the crystallization temperature of the crystalline polyester C is Tc (c) [° C.].
Formula (I): 50 ≤ Tg (a) ≤ 60
Formula (II): 1.10 ≦ SP (a) −SP (c) ≦ 1.50
Formula (III): 5 ≤ Tc (c)-Tg (a) ≤ 17

  According to the present invention, a toner excellent in low-temperature fixability, heat-resistant storage stability, and blurring suppression can be obtained.

[toner]
The toner of the present invention is a pulverized toner by melt kneading method containing amorphous polyester A and crystalline polyester C,
The amorphous polyester A is a polycondensation of an alcohol component containing an aliphatic diol having a hydroxyl group bonded to a secondary carbon atom having 3 to 5 carbon atoms and a carboxylic acid component containing an aromatic dicarboxylic acid compound. Is a thing,
The crystalline polyester C is a polycondensate of an alcohol component containing an aliphatic diol and a carboxylic acid component containing an aliphatic dicarboxylic acid compound,
The glass transition point Tg (a) [° C.] of the amorphous polyester A satisfies the following formula (I):
The solubility parameter of the amorphous polyester A is SP (a) [(cal / cm ³ ) ^1/2 ], and the solubility parameter of the crystalline polyester C is SP (c) [(cal / cm ³ ) ^1/2 ]. When the crystallization temperature of the crystalline polyester C is Tc (c) [° C.], the following formulas (II) and (III) are satisfied.
Formula (I): 50 ≤ Tg (a) ≤ 60
Formula (II): 1.10 ≦ SP (a) −SP (c) ≦ 1.50
Formula (III): 5 ≦ Tc (c)-Tg (a) ≦ 17
According to the present invention, a toner excellent in low-temperature fixability, heat-resistant storage stability, and blurring suppression can be obtained. The reason why the effect of the present invention is obtained is not clear, but is considered as follows.
By satisfying the relationship of the formula (I), a toner exhibiting excellent low-temperature fixability, heat-resistant storage stability, and blurring suppression can be obtained.
By satisfying the relationship of the formula (II), the dispersibility of the crystalline polyester C can be enhanced while suppressing the compatibility between the amorphous polyester A and the crystalline polyester C. In addition, a toner excellent in suppressing blurring can be obtained.
Furthermore, by satisfying the relationship of the formula (III), even when the binder resin composition is melt-kneaded, the domain of the crystalline polyester C is easily formed in the cooling process, and the crystalline polyester C is finely formed in the toner. Since the toner is dispersed, a toner excellent in low-temperature fixability, heat-resistant storage stability and blurring suppression can be obtained.

[Formulas (I) to (III)]
With respect to formula (I), Tg (a) is 50 or more, preferably 52 or more, from the viewpoint of obtaining a toner excellent in low-temperature fixability, heat-resistant storage stability, and blurring of the obtained toner. , 60 or less, preferably 58 or less.

  With respect to formula (II), [SP (a) -SP (c)] is 1.10 or more, preferably 1.20 or more, from the viewpoint of obtaining a toner excellent in low-temperature fixability, heat-resistant storage stability, and blurring suppression. And 1.50 or less, preferably 1.40 or less.

  With respect to formula (III), [Tc (c) -Tg (a)] is 5 or more, preferably 6 or more, from the viewpoint of obtaining a toner excellent in low-temperature fixability, heat-resistant storage stability, and blurring. More preferably, it is 8 or more, more preferably 10 or more, and 17 or less, preferably 16 or less, more preferably 15 or less.

The glass transition point Tg (a) in the present invention is measured by a method observed by differential scanning calorimetry described in Examples.
SP values in the present invention: SP (a) and SP (c) are proposed by Fedors et al. [POLYMER ENGINEERING AND SCIENCE, FEBRUARY, 1974, Vol.14, No.2, ROBERT F. FEDORS. (Pp.147-154) )].
The crystallization temperature Tc (c) in the present invention is measured by a method observed by differential scanning calorimetry described in Examples.
When two or more types of amorphous polyester are contained in the toner (provided that the content of the amorphous polyester is 10 parts by mass or more), at least the amorphous having the lowest softening point The polyester may satisfy the conditions of the above formulas (I) to (III) as the amorphous polyester A.
When two or more types of crystalline polyester are contained in the toner (however, the crystalline polyester content is 10 parts by mass or more), at least the crystalline polyester having the lowest softening point is crystalline. As the polyester C, the conditions of the above formulas (I) to (III) may be satisfied.

[Amorphous polyester A]
Amorphous polyester A is a polycondensate of an alcohol component containing an aliphatic diol having a hydroxyl group bonded to a secondary carbon atom having 3 to 5 carbon atoms and a carboxylic acid component containing an aromatic dicarboxylic acid compound. It is.

  As the aliphatic diol having a hydroxyl group bonded to a secondary carbon atom having 3 to 5 carbon atoms, 1,2-propanediol, 1,2-butanediol, 1,3 from the viewpoint of improving heat-resistant storage stability -Butanediol, 2,3-butanediol, 1,2-pentanediol, 1,3-pentanediol, 1,4-pentanediol, 2,3-pentanediol, 2,4-pentanediol and the like. Among these, 1,2-propanediol is more preferable.

  The content of the aliphatic diol having a hydroxyl group bonded to a secondary carbon atom is preferably 50 mol% or more, more preferably 60 mol% or more, and still more preferably, from the viewpoint of improving the heat resistant storage stability in the alcohol component. 70 mol% or more, more preferably 80 mol% or more, and 100 mol% or less, and more preferably 100 mol%.

  In addition to the aliphatic diol having a hydroxyl group bonded to a secondary carbon atom, the alcohol component is preferably an α, ω-fatty acid having a hydroxyl group at the end of the carbon chain from the viewpoint of further improving the low-temperature fixability. Group diols, more preferably α, ω-linear alkanediols. The carbon number of the α, ω-aliphatic diol is preferably 3 or more, more preferably 4 or more, and is preferably 5 or less, more preferably 4 or less, and more preferably 4. As the α, ω-linear alkanediol, 1,4-butanediol is preferred.

  When the α, ω-aliphatic diol is included as the alcohol component of the amorphous polyester A, the content of α, ω-aliphatic diol, preferably α, ω-linear alkane diol is low in the alcohol component. From the viewpoint of further improving the fixability, it is preferably 10 mol% or more, more preferably 15 mol% or more, and from the viewpoint of further improving the heat resistant storage stability, preferably 50 mol% or less, more preferably 40 mol%. % Or less, more preferably 30 mol% or less, more preferably 25 mol% or less.

  When an α, ω-aliphatic diol is included as the alcohol component of the amorphous polyester A, the molar ratio of the aliphatic diol having a hydroxyl group bonded to a secondary carbon atom and the α, ω-aliphatic diol (second The aliphatic diol having a hydroxyl group bonded to a secondary carbon atom / α, ω-aliphatic diol) is preferably 0.1 or more, more preferably 0.5 or more, still more preferably 1 or more, from the viewpoint of further improving the heat resistant storage stability. More preferably, it is 2 or more, and from the viewpoint of further improving the low-temperature fixability, it is preferably 10 or less, more preferably 8 or less, still more preferably 5 or less, and further preferably 3 or less.

  The total content of the aliphatic diol having a hydroxyl group bonded to the secondary carbon atom and the α, ω-aliphatic diol is the alcohol component of the amorphous polyester A from the viewpoint of further improving the low-temperature fixability and the heat-resistant storage stability. Among them, preferably 60 mol% or more, more preferably 80 mol% or more, still more preferably 90 mol% or more, still more preferably 95 mol% or more, and 100 mol% or less, and more preferably 100 mol% or more. Mol%.

  As other alcohol components, aromatic diols such as alkylene oxide adducts of bisphenol A, aliphatic diols having 6 or more carbon atoms, trihydric or higher alcohols such as glycerin, etc. are used as long as the effects of the present invention are not impaired. May be.

In the carboxylic acid component, examples of the aromatic dicarboxylic acid compound include phthalic acid, isophthalic acid, terephthalic acid, and the like. Among these, terephthalic acid is preferable.
In the present invention, the dicarboxylic acid compound refers to a dicarboxylic acid, an anhydride thereof, and an alkyl ester having an alkyl group having 1 to 3 carbon atoms. Among these, a dicarboxylic acid is preferable.

In addition to the aromatic dicarboxylic acid compound, the carboxylic acid component preferably contains a trivalent or higher carboxylic acid compound, more preferably a trivalent carboxylic acid compound, from the viewpoint of further improving the low-temperature fixability.
As the trivalent or higher carboxylic acid compound, for example, preferably a carbon number of 4 or more and 30 or less, more preferably a carbon number of 4 or more and 20 or less, and further preferably a carbon number of 4 or more and 10 or less, a trivalent or higher carboxylic acid, These acid anhydrides, derivatives such as alkyl esters having an alkyl group having 1 to 3 carbon atoms, and the like can be mentioned. Specifically, 1,2,4-benzenetricarboxylic acid (trimellitic acid), 2,5,7-naphthalenetricarboxylic acid, 1,2,4,5-benzenetetracarboxylic acid (pyromellitic acid) or their 1,2,4-benzenetricarboxylic acid (trimellitic acid) or its acid anhydride from the viewpoint of further suppressing fogging and from the viewpoint of improving charging stability and suppressing fogging 1,2,4-benzenetricarboxylic acid anhydride (trimellitic anhydride) is more preferable.

  The content of the trivalent or higher carboxylic acid compound is preferably 0.1 mol% or more, more preferably 0.5 mol in the carboxylic acid component of the amorphous polyester A, from the viewpoint of further improving the low-temperature fixability and heat-resistant storage stability. % Or more, more preferably 1 mol% or more, and preferably 20 mol% or less, more preferably 10 mol% or less, still more preferably 5 mol% or less.

  In addition to the aromatic dicarboxylic acid compound, the carboxylic acid component is preferably succinic acid and carbon substituted with an alkyl group having 8 to 20 carbon atoms from the viewpoint of improving charging stability and suppressing the generation of fog. A succinic acid compound selected from the group consisting of succinic acid substituted with an alkenyl group having a number of 8 or more and 20 or less is included. Specific examples of the succinic acid compounds include dodecyl succinic acid, dodecenyl succinic acid, tetrapropenyl succinic acid, decenyl succinic acid, acid anhydrides thereof, alkyl esters having 1 to 3 carbon atoms, and the like. Especially, dodecenyl succinic acid, tetrapropenyl succinic acid, or those acid anhydrides are preferable, and dodecenyl succinic acid anhydride is more preferable.

  The content of the succinic acid-based compound is preferably 3 mol% in the carboxylic acid component of the amorphous polyester A from the viewpoint of improving the charging stability and suppressing the occurrence of fogging and further improving the low-temperature fixability. Above, more preferably 5 mol% or more, more preferably 10 mol% or more, and from the viewpoint of further improving the heat resistant storage stability of the toner, preferably 50 mol% in the carboxylic acid component of the amorphous polyester A. Below, more preferably 40 mol% or less, still more preferably 30 mol% or less, and still more preferably 25 mol% or less.

  Examples of other carboxylic acid components include fumaric acid, maleic acid, succinic acid, glutaric acid, adipic acid, sebacic acid and the like.

  The alcohol component may contain a monovalent alcohol, and the carboxylic acid component may contain a monovalent carboxylic acid compound as appropriate.

  The equivalent molar ratio of the carboxylic acid component and the alcohol component (COOH group / OH group) is preferably from 0.70 to 1.15, more preferably from 0.75 to 1.10, from the viewpoint of improving the molecular weight while reducing the acid value of the polyester. More preferably, it is 0.75 or more and 0.95 or less.

  The polycondensation reaction between the alcohol component and the carboxylic acid component is not particularly limited. For example, in an inert gas atmosphere, as necessary, an esterification catalyst, an esterification cocatalyst, a polymerization inhibitor, etc. Can be carried out at a temperature of 140 ° C. or higher, preferably 180 ° C. or higher, and 250 ° C. or lower, preferably 240 ° C. or lower. Examples of the esterification catalyst include tin compounds such as dibutyltin oxide and di (2-ethylhexanoic acid) tin (II), titanium compounds such as titanium diisopropylate bistriethanolamate, and the like, and can be used together with the esterification catalyst. Examples of the esterification promoter include gallic acid. The amount of the esterification catalyst used is preferably 0.01 parts by mass or more, more preferably 0.1 parts by mass or more, and preferably 1.5 parts by mass or less, more preferably 100 parts by mass of the total amount of the alcohol component and the carboxylic acid component. Preferably it is 1.0 mass part or less. The amount of esterification promoter used is preferably 0.001 parts by mass or more, more preferably 0.01 parts by mass or more, and preferably 0.5 parts by mass or less, with respect to 100 parts by mass of the total amount of the alcohol component and the carboxylic acid component. More preferably, it is 0.1 parts by mass or less.

  The number average molecular weight of the amorphous polyester A is preferably 4,000 or more, more preferably 4,500 or more from the viewpoint of suppressing blurring, and preferably 10,000 or less, more preferably from the viewpoint of further improving the low-temperature fixability. 7,000 or less. The number average molecular weight in the case of containing two or more kinds of amorphous polyester is the value of the amorphous polyester having the lowest softening point.

  Further, the amorphous polyester A may be modified to such an extent that the characteristics are not substantially impaired. For example, the modified polyester may be grafted or blocked with phenol, urethane, epoxy or the like by the method described in JP-A-11-133668, JP-A-10-239903, JP-A-8-20636, etc. Polyester.

  The softening point of the amorphous polyester A is preferably 80 ° C. or higher, more preferably 95 ° C. or higher, from the viewpoint of further improving the heat resistant storage stability, and preferably 125 ° C. from the viewpoint of further improving the low temperature fixability. C. or lower, more preferably 115.degree. C. or lower.

  The glass transition point [Tg (a)] of the amorphous polyester A is as defined in the formula (I).

  From the viewpoint of improving productivity, the acid value of the amorphous polyester A is preferably 1 mgKOH / g or more, more preferably 3 mgKOH / g or more, and further preferably 4 mgKOH / g or more. Therefore, it is preferably 30 mgKOH / g or less, more preferably 25 mgKOH / g or less, further preferably 20 mgKOH / g or less, and further preferably 10 mgKOH / g or less.

  The crystallinity of polyester is represented by the crystallinity index defined by the ratio between the softening point and the maximum endothermic peak temperature measured by a differential scanning calorimeter, that is, the value of [softening point / maximum endothermic peak temperature]. The crystalline polyester is a resin having a crystallinity index of 0.6 or more, preferably 0.7 or more, more preferably 0.9 or more, and 1.4 or less, preferably 1.3 or less, more preferably 1.2 or less, and even more preferably 1.1 or less. . On the other hand, the amorphous polyester is a resin having a crystallinity index exceeding 1.4, preferably exceeding 1.5, more preferably 1.6 or more, or less than 0.6, preferably 0.5 or less, more preferably 0.4 or less. The crystallinity of the polyester can be adjusted by the type and ratio of the raw material monomers, production conditions (for example, reaction temperature, reaction time, cooling rate) and the like. The highest endothermic peak temperature refers to the temperature of the peak on the highest temperature side among the observed endothermic peaks. In crystalline polyester, the highest endothermic peak temperature is the melting point.

SP value of amorphous polyester A [solubility parameter: (cal / cm ³ ) ^1/2 ]: SP (a) is preferably 10.00 or more, more preferably 10.50 or more, further preferably 11.00 or more, and It is preferably 12.50 or less, more preferably 12.00 or less, and still more preferably 11.50 or less.

In the toner, the content of the amorphous polyester A is preferably 20% by mass or more, more preferably 30% by mass or more, still more preferably 40% by mass or more based on the total amount of the binder resin. Preferably it is 90 mass% or less, More preferably, it is 80 mass% or less, More preferably, it is 70 mass% or less, More preferably, it is 60 mass% or less.
In the present invention, the total amount of binder resin means the total amount of amorphous polyester A, amorphous polyester AH, and crystalline polyester C.

[Amorphous polyester AH]
The toner preferably further contains amorphous polyester AH having a higher softening point than amorphous polyester A from the viewpoint of high temperature offset resistance.
When the amorphous polyester AH is contained, the following formula (IV) is preferably satisfied when the solubility parameter of the amorphous polyester AH is SP (ah) [(cal / cm ³ ) ^1/2 ].
Formula (IV): | SP (ah)-SP (a) | ≦ 1.00
Regarding the formula (IV), | SP (ah) −SP (a) | is preferably 0.80 or less, more preferably from the viewpoint of obtaining a toner excellent in low-temperature fixability, heat-resistant storage stability, and suppression of blurring. 0.70 or less.
Note that the calculation method of SP (ah) is the same as SP (a) described above.

The amorphous polyester AH is preferably a polycondensation of an alcohol component containing an aliphatic diol having a hydroxyl group bonded to a secondary carbon atom having 3 to 5 carbon atoms and a carboxylic acid component containing an aromatic dicarboxylic acid. It is a thing.
The preferred examples of the amorphous polyester AH are the same as the preferred examples of the alcohol component and the carboxylic acid component of the amorphous polyester A described above unless otherwise specified.

  The softening point of the amorphous polyester AH is preferably 110 ° C. or higher, more preferably 130 ° C. or higher from the viewpoint of high-temperature offset resistance, and preferably 170 ° C. or lower from the viewpoint of further improving the low-temperature fixability. More preferably, it is 160 ° C. or lower.

  The difference between the softening points of the amorphous polyester A and the amorphous polyester AH is preferably 10 ° C or higher, more preferably 20 ° C or higher, from the viewpoint of further improving the high temperature offset resistance and the low temperature fixability, and From the viewpoint of chargeability, it is preferably 60 ° C. or lower, more preferably 50 ° C. or lower.

  In the toner, the content of the amorphous polyester AH is preferably 20% by mass or more, more preferably 30% by mass or more, still more preferably 40% by mass or more based on the total amount of the binder resin. The content is preferably 90% by mass or less, more preferably 80% by mass or less, still more preferably 70% by mass or less, still more preferably 60% by mass or less, and still more preferably 50% by mass or less.

  From the viewpoint of durability and productivity, the mass ratio of the amorphous polyester A to the amorphous polyester AH (amorphous polyester A / amorphous polyester AH) is preferably 20/80 or more, more preferably 40 / From the viewpoint of further improving the low-temperature fixability, it is preferably 80/20 or less, more preferably 60/40 or less.

  In the amorphous polyester A, a known amorphous resin other than the amorphous polyester, for example, a vinyl resin such as styrene-acrylic resin, an epoxy resin, a polycarbonate resin, and the like, as long as the effects of the present invention are not impaired. Other resins such as a polyurethane resin may be used in combination, but the total content of the amorphous polyester is preferably 60% by mass or more in the amorphous polyester A from the viewpoint of further improving the low-temperature fixability. More preferably, it is 70 mass% or more, More preferably, it is 80 mass% or more.

(Crystalline polyester C)
Crystalline polyester C is a crystalline polyester that is a polycondensate of an alcohol component containing an aliphatic diol and a carboxylic acid component containing an aliphatic dicarboxylic acid compound.

The alcohol component of the crystalline polyester C contains an aliphatic diol, preferably an α, ω-aliphatic diol, from the viewpoint of enhancing the crystallinity of the polyester and improving the low-temperature fixability and heat-resistant storage stability of the toner. More preferably, α, ω-linear alkanediol is contained.
The carbon number of the aliphatic diol is preferably 2 or more, and is preferably 20 or less, more preferably 16 or less, still more preferably 14 or less, and still more preferably 12 or less.
Aliphatic diols include ethylene glycol, 1,4-butanediol, 1,4-butenediol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, 1,7-heptanediol, 1, Examples include 8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,12-dodecanediol, 1,14-tetradecanediol, and the like, from the viewpoint of improving heat storage stability and curling suppression. At least one selected from the group consisting of ethylene glycol, 1,4-butanediol, 1,4-butenediol, 1,10-decanediol, 1,12-dodecanediol, and 1,14-tetradecanediol is preferable.

  The content of the aliphatic diol is preferably 70 mol% or more, more preferably 90 mol% or more, still more preferably 95 mol% or more, and 100 mol in the alcohol component from the viewpoint of enhancing the crystallinity of the polyester. % Or less, and more preferably 100 mol%.

  The alcohol component may contain polyhydric alcohol components other than aliphatic diols, and aromatics such as bisphenol A alkylene oxide adducts such as bisphenol A ethylene oxide adducts and bisphenol A propylene oxide adducts. Diols: Trivalent or higher alcohols such as glycerin, pentaerythritol, trimethylolpropane, sorbitol, 1,4-sorbitan, etc. may be mentioned.

  The carboxylic acid component of the crystalline polyester C contains an aliphatic dicarboxylic acid compound from the viewpoint of enhancing the crystallinity of the polyester and improving the low-temperature fixability and heat-resistant storage stability of the toner.

The number of carbon atoms of the aliphatic dicarboxylic acid compound is preferably 2 or more, more preferably 9 or more, and is preferably 20 or less, more preferably 16 or less, and even more preferably 14 or less. However, the carbon number of the aliphatic dicarboxylic acid compound here excludes the carbon number of the alkyl ester in the case of an alkyl ester.
Examples of the aliphatic dicarboxylic acid compounds include maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, succinic acid, adipic acid, azelaic acid, sebacic acid, decanedioic acid, dodecanedioic acid, and tetradecanedioic acid. From the viewpoint of improving heat-resistant storage stability and curling suppression, at least one selected from the group consisting of fumaric acid, succinic acid, adipic acid, sebacic acid, decanedioic acid, dodecanedioic acid, and tetradecanedioic acid is preferable. .

  The content of the aliphatic dicarboxylic acid compound is preferably 70 mol% or more, more preferably 90 mol% or more, still more preferably 95 mol% or more, in the carboxylic acid component, from the viewpoint of increasing the crystallinity of the polyester. And it is preferably 100 mol% or less, and more preferably 100 mol%.

  The carboxylic acid component may contain a polyvalent carboxylic acid compound other than the aliphatic dicarboxylic acid compound. Examples of the polyvalent carboxylic acid compound include aromatics such as phthalic acid, isophthalic acid, and terephthalic acid. Dicarboxylic acid compounds; cycloaliphatic dicarboxylic acids such as cyclohexanedicarboxylic acid; trivalent or higher aromatic carboxylic acids such as trimellitic acid, 2,5,7-naphthalenetricarboxylic acid, pyromellitic acid, and anhydrides thereof; Examples thereof include alkyl esters having 1 to 3 carbon atoms in the alkyl group.

  In addition, a monovalent alcohol may be appropriately contained in the alcohol component, and a monovalent carboxylic acid compound may be appropriately contained in the carboxylic acid component from the viewpoint of adjusting the molecular weight.

  The crystalline polyester C is preferably a crystalline polyester that is a polycondensate of an alcohol component containing an aliphatic diol and a carboxylic acid component containing an aliphatic dicarboxylic acid compound, and the aliphatic diol and the aliphatic dicarboxylic acid type. The number of carbon atoms of the compound is 9 or more and 14 or less. The content of the compound having 9 to 14 carbon atoms is preferably 30 mol% or more, more preferably 40 mol% or more, from the viewpoint of enhancing the crystallinity of the polyester in the total amount of the alcohol component and the carboxylic acid component, And preferably it is 80 mol% or less, More preferably, it is 70 mol%, More preferably, it is 60 mol% or less.

  From the viewpoint of adjusting the softening point of the polyester, the equivalent ratio of the carboxylic acid component and the alcohol component of the crystalline polyester C (COOH group / OH group) is preferably 0.70 or more, more preferably 0.75 or more, and preferably Is 1.10 or less, more preferably 1.00 or less.

  A suitable synthesis method and conditions for the crystalline polyester C are the same as those described for the amorphous polyester A.

  In addition, crystalline polyester contains polyester compounded or modified with other resins within a range not impairing the effects of the present invention. Examples of the polyester compounded with another resin include a composite resin in which a styrene resin such as a styrene / acrylic copolymer is compounded with polyester. Examples of the modified polyester include urethane-modified polyester in which the polyester is modified with a urethane bond, and epoxy-modified polyester in which the polyester is modified with an epoxy bond.

  The crystallization temperature Tc (c) of the crystalline polyester C is preferably 45 ° C. or higher, more preferably 50 ° C. or higher, more preferably 55 ° C. or higher, from the viewpoint of further improving the heat-resistant storage stability of the toner. From the viewpoint of further improving the low-temperature fixability of the toner, it is preferably 90 ° C. or lower, more preferably 80 ° C. or lower, and still more preferably 70 ° C. or lower.

  The softening point of the crystalline polyester C is preferably 60 ° C. or higher, more preferably 70 ° C. or higher, and still more preferably 80 ° C. or higher, from the viewpoint of further improving the heat-resistant storage stability of the toner. From the viewpoint of further improving the temperature, it is preferably 120 ° C. or lower, more preferably 115 ° C. or lower, and still more preferably 110 ° C. or lower.

  The softening point of the crystalline polyester C is preferably lower than the softening point of the amorphous polyester A from the viewpoint of further improving the low-temperature fixability of the toner, and the difference is preferably 5 ° C. or more, more preferably Is 8 ° C or higher, more preferably 10 ° C or higher, and preferably 60 ° C or lower, more preferably 40 ° C or lower, and further preferably 20 ° C or lower.

  The melting point of the crystalline polyester C is preferably 70 ° C. or higher, more preferably 75 ° C. or higher, and still more preferably 80 ° C. or higher, from the viewpoint of further improving the heat-resistant storage stability and blurring suppression of the toner. From the viewpoint of further improving the low-temperature fixability, it is preferably 120 ° C. or lower, more preferably 110 ° C. or lower, and still more preferably 100 ° C. or lower.

  The SP value of the crystalline polyester C: SP (c) is preferably 9.00 or more, more preferably 9.60 or more, and preferably 10.50 or less, from the viewpoint of further improving the heat-resistant storage stability of the toner and suppressing blurring. More preferably, it is 10.00 or less.

  In the toner, the content of the crystalline polyester C is preferably 1% by mass or more, more preferably 3% by mass or more, and further preferably from the total amount of the binder resin, from the viewpoint of further improving the low-temperature fixability. From the viewpoint of further improving the heat-resistant storage stability and suppression of blurring of the toner, it is preferably 30% by mass or less, more preferably 20% by mass or less, and still more preferably 10% by mass or less.

  The mass ratio of the amorphous polyester A to the crystalline polyester C (amorphous polyester A / crystalline polyester C) is preferably 70/30 or more, more preferably 80/20, from the viewpoint of further improving the heat resistant storage stability. More preferably, it is 90/10 or more, and from the viewpoint of low-temperature fixability, it is preferably 97/3 or less, more preferably 95/5 or less.

  The mass ratio of the total amount of the amorphous polyester and the crystalline polyester C (amorphous polyester / crystalline polyester C) is preferably 70/30 or more, more preferably 80 /, from the viewpoint of further improving the heat resistant storage stability. It is 20 or more, more preferably 90/10 or more, and from the viewpoint of low-temperature fixability, it is preferably 97/3 or less, more preferably 95/5 or less.

  To the toner of the present invention, known amorphous resins other than the above-mentioned amorphous polyesters A and AH, for example, vinyl resins such as styrene-acrylic resins, epoxy resins, and the like, as long as the effects of the present invention are not impaired. Other resins such as polycarbonate resin and polyurethane resin may be used in combination.

From the viewpoint of further improving the low-temperature fixability, the total content of the amorphous polyester A and the crystalline polyester C is preferably 30% by mass or more, more preferably 40% by mass or more, and still more preferably from the resin component of the toner. It is 50% by mass or more and 100% by mass or less, preferably 90% by mass or less, more preferably 80% by mass or less, and more preferably 70% by mass or less.
The total content of the amorphous polyester A, the amorphous polyester AH, and the crystalline polyester C is preferably 60% by mass or more, more preferably 70% in the resin component of the toner from the viewpoint of further improving the low-temperature fixability. It is not less than mass%, more preferably not less than 80 mass% and not more than 100 mass%.

  To the toner, colorants, release agents, charge control agents, magnetic powders, fluidity improvers, conductivity modifiers, reinforcing fillers such as fibrous substances, antioxidants, cleaning improvers, etc. are added. An agent may be contained, and a colorant, a release agent and a charge control agent are preferably contained.

[Colorant]
As the colorant, dyes, pigments and the like used as toner colorants can be used. For example, carbon black, phthalocyanine blue, permanent brown FG, brilliant first scarlet, pigment green B, rhodamine-B base, solvent red 49, solvent red 146, solvent blue 35, quinacridone, carmine 6B, isoindoline, disazo yellow . In the present invention, the toner particles may be either black toner or color toner.

  The content of the colorant is preferably 1 part by mass or more, more preferably 2 parts by mass or more, and preferably 40 parts by mass with respect to 100 parts by mass of the binder resin from the viewpoint of improving the image density of the toner. Part or less, more preferably 10 parts by weight or less.

〔Release agent〕
Release agents include polypropylene wax, polyethylene wax, polypropylene polyethylene copolymer wax, microcrystalline wax, paraffin wax, Fischer-Tropsch wax, sazol wax and other hydrocarbon waxes and their oxides, carnauba wax, and montan wax. And ester waxes such as deoxidized wax and fatty acid ester wax, fatty acid amides, fatty acids, higher alcohols, fatty acid metal salts and the like, and these can be used alone or in admixture of two or more. . From the viewpoint of improving the heat resistant storage stability of the toner, polypropylene wax is preferred.

  The melting point of the release agent is preferably 60 ° C. or higher, more preferably 70 ° C. or higher from the viewpoint of further improving the heat resistant storage stability of the toner, and preferably 150 ° C. or lower from the viewpoint of high temperature offset resistance.

  The content of the release agent is preferably 0.5 parts by mass or more, more preferably 0.8 parts by mass or more, and further preferably 100 parts by mass of the binder resin, from the viewpoint of improvement in low-temperature fixability of the toner and offset resistance. Is 1.0 part by mass or more, and from the viewpoint of toner durability, it is preferably 10 parts by mass or less, more preferably 6 parts by mass or less, and still more preferably 4 parts by mass or less.

[Charge control agent]
The charge control agent is not particularly limited, and may contain either a positively chargeable charge control agent or a negatively chargeable charge control agent.

  Examples of positively chargeable charge control agents include nigrosine dyes such as “Nigrosine Base EX”, “Oil Black BS”, “Oil Black SO”, “Bontron N-01”, “Bontron N-04”, “Bontron N-07 ”,“ Bontron N-09 ”,“ Bontron N-11 ”(manufactured by Orient Chemical Co., Ltd.) and the like; triphenylmethane dyes containing tertiary amines as side chains, quaternary ammonium salt compounds such as“ Bontron P-51 "(manufactured by Orient Chemical Industry Co., Ltd.), cetyltrimethylammonium bromide," COPY CHARGE PX VP435 "(manufactured by Clariant Co., Ltd.), etc .; Imidazole derivatives such as “PLZ-2001” and “PLZ-8001” (manufactured by Shikoku Kasei Kogyo Co., Ltd.); styrene-acrylic resins such as “FCA-701PT” (Fujikura Chemical) Etc., Ltd.) Co., Ltd., and the like.

  In addition, as the negatively chargeable charge control agent, metal-containing azo dyes such as “Varifast Black 3804”, “Bontron S-31”, “Bontron S-32”, “Bontron S-34”, “Bontron S-36” (Above, manufactured by Orient Chemical Co., Ltd.), “Eisenspiron Black TRH”, “T-77” (above, manufactured by Hodogaya Chemical Co., Ltd.), etc .; metal compounds of benzylic acid compounds such as “LR- 147 "," LR-297 "(manufactured by Nippon Carlit Co., Ltd.), etc .; metal compounds of salicylic acid compounds, such as" Bontron E-81 "," Bontron E-84 "," Bontron E-88 "," Bontron " "E-304" (made by Orient Chemical Co., Ltd.), "TN-105" (made by Hodogaya Chemical Co., Ltd.), etc .; copper phthalocyanine dyes; quaternary ammonium salts such as "COPY CHARGE NX VP434" (Clariant) Product), Nitroimidazole Derivatives and the like; organometallic compounds and the like.

  The content of the charge control agent is preferably 0.01 parts by mass or more, more preferably 0.2 parts by mass or more, and preferably 10 parts by mass with respect to 100 parts by mass of the binder resin from the viewpoint of charge stability of the toner. Part or less, more preferably 5 parts by weight or less, still more preferably 3 parts by weight or less, and still more preferably 2 parts by weight or less.

[Production method]
The toner is a pulverized toner obtained by a pulverization method. For example, a binder resin and a colorant, and if necessary, raw materials such as a release agent and a charge control agent are uniformly mixed in a mixer and then melt-kneaded in a kneader. Then, it can be manufactured by cooling, pulverizing and classifying.

The toner production method preferably includes the following step 1 and step 2.
Step 1: Step of melt-kneading a toner raw material mixture containing a binder resin containing amorphous polyester A and crystalline polyester C Step 2: Step of pulverizing and classifying the melt-kneaded product obtained in Step 1

  In step 1, it is more preferable to melt knead the colorant, and it is preferable to melt and knead other additives such as other resins, release agents, and charge control agents.

  The toner raw materials such as the binder resin, the colorant, the charge control agent, and the release agent are preferably mixed in advance with a mixer such as a Henschel mixer or a ball mill and then supplied to the kneader.

  The melt-kneading can be performed using a known kneader such as a closed kneader, a uniaxial or biaxial extruder, an open roll type kneader. A twin screw extruder is used from the viewpoint that additives such as a colorant, a charge control agent, and a release agent can be efficiently and highly dispersed in the toner without repeating kneading and using a dispersion aid. It is preferable.

  The twin-screw extruder has a kneading part sealed, and can easily melt each material by kneading heat generated during kneading.

The set temperature of the twin-screw extruder is not affected by the melting characteristics of the toner raw material due to the structure of the extruder and can be easily melt-mixed at the intended temperature.
The set temperature (barrel set temperature) of the twin-screw extruder is, for example, preferably 80 ° C. or higher, more preferably 90 ° C. or higher, and preferably 160 ° C. or lower, more preferably 140 ° C. or lower.

  Rotational peripheral speed is the same direction from the viewpoint of improving the dispersibility of additives such as colorants, charge control agents, and release agents in the toner, reducing the mechanical force during melt kneading, and suppressing heat generation. In the case of a rotary twin screw extruder, it is preferably 0.05 m / sec or more, more preferably 0.10 m / sec or more, more preferably 0.15 m / sec or more, and preferably 5 m / sec or less, more preferably 1.0 m. / sec or less, more preferably 0.40 m / sec or less.

  The melt-kneaded product obtained in step 1 is cooled to such an extent that it can be crushed, and then subjected to subsequent step 2.

  In step 2, the melt-kneaded product obtained in step 1 is pulverized and classified.

  The pulverization process may be performed in multiple stages. For example, a resin kneaded product obtained by curing a melt-kneaded product may be coarsely pulverized to about 1 to 5 mm and further pulverized to a desired particle size.

  The pulverizer used in the pulverization step is not particularly limited, and examples of the pulverizer suitably used for coarse pulverization include a hammer mill, an atomizer, and a rotplex. Further, examples of the pulverizer suitably used for fine pulverization include a fluidized bed jet mill, a collision plate jet mill, and a rotary mechanical mill. From the viewpoint of grinding efficiency, it is preferable to use a fluidized bed jet mill or a collision plate jet mill, and more preferably a fluidized bed jet mill.

  Examples of the classifier used in the classification process include a rotor classifier, an airflow classifier, an inertia classifier, and a sieve classifier. In the classification step, the pulverized product that has been removed due to insufficient pulverization may be subjected to the pulverization step again, and the pulverization step and the classification step may be repeated as necessary.

  In the toner of the present invention, it is preferable to use an external additive in order to improve transferability. Examples of the external additive include inorganic fine particles such as silica, alumina, titania, zirconia, tin oxide and zinc oxide, and organic fine particles such as resin particles such as melamine resin fine particles and polytetrafluoroethylene resin fine particles. The above may be used in combination. Among these, silica is preferable, and hydrophobic silica that has been subjected to a hydrophobic treatment is more preferable from the viewpoint of toner transferability.

  Examples of the hydrophobizing agent for hydrophobizing the surface of silica particles include hexamethyldisilazane (HMDS), dimethyldichlorosilane (DMDS), silicone oil, octyltriethoxysilane (OTES), and methyltriethoxysilane. It is done.

  The average particle diameter of the external additive is preferably 10 nm or more, more preferably 15 nm or more, and preferably 250 nm or less, more preferably 200 nm or less, from the viewpoint of chargeability, fluidity, and transferability of the toner. Preferably it is 90 nm or less.

  The content of the external additive is preferably 0.05 parts by mass or more, and more preferably 0.1 parts by mass with respect to 100 parts by mass of the toner particles before being processed with the external additive, from the viewpoint of chargeability, fluidity, and transferability of the toner. It is not less than part by mass, more preferably not less than 0.3 part by mass, and preferably not more than 5 parts by mass, more preferably not more than 3 parts by mass.

The volume median particle size (D ₅₀ ) of the toner of the present invention is preferably 3 μm or more, more preferably 4 μm or more, and preferably 15 μm or less, more preferably 10 μm or less. In the present specification, the volume median particle size (D ₅₀ ) means a particle size at which the cumulative volume frequency calculated by the volume fraction is 50% calculated from the smaller particle size. Also, when processing a toner external additive, the volume median particle size of the toner particles prior to treatment with an external additive (D ₅₀₎ a toner having a volume-median particle size (D ₅₀₎ .

The toner of the present invention is used as a toner for developing an electrostatic image.
The toner of the present invention can be used in an image forming apparatus of a one-component development system or a two-component development system as a one-component development toner as it is or as a two-component development toner mixed with a carrier.

  EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. The physical properties of the resin and the like were measured by the following method.

[Softening point of resin]
Using a flow tester “CFT-500D” (manufactured by Shimadzu Corporation), a 1 g sample was heated at a heating rate of 6 ° C./min, and a load of 1.96 MPa was applied by a plunger, with a diameter of 1 mm and a length of 1 mm. Extrude from nozzle. The amount of plunger drop of the flow tester is plotted against the temperature, and the temperature at which half of the sample flows out is taken as the softening point.

[Maximum peak temperature of resin endotherm, melting point of crystalline polyester]
Using a differential scanning calorimeter “Q-100” (manufactured by TA Instruments Japan Co., Ltd.), 0.01 to 0.02 g of sample is weighed into an aluminum pan, and the temperature is lowered from room temperature (25 ° C.) to 10 ° C./min. Cool to 0 ° C and maintain at 0 ° C for 1 minute. Thereafter, the measurement is performed at a heating rate of 10 ° C./min. Among the observed endothermic peaks, the temperature of the peak on the highest temperature side is defined as the highest endothermic peak temperature. In crystalline polyester, the highest peak temperature of endotherm was taken as the melting point.

[Glass transition point of resin: Tg (a), etc.]
Using a differential scanning calorimeter “Q-20” (manufactured by TA Instruments Japan Co., Ltd.), 0.01 to 0.02 g of sample is weighed into an aluminum pan, heated to 200 ° C., and the temperature drop rate from that temperature is 10 ° C. Cool to 0 ° C at / min. Next, the sample is heated at a heating rate of 10 ° C./min, and the endothermic peak is measured. The glass transition point is defined as the temperature at the intersection of the base line extension below the maximum peak temperature of endotherm and the tangent line indicating the maximum slope from the peak rising portion to the peak apex.

[Resin crystallization temperature: Tc (c), etc.]
Using a differential scanning calorimeter “Q-20” (manufactured by TA Instruments Japan Co., Ltd.), 0.01 to 0.02 g of sample is weighed into an aluminum pan, heated to 200 ° C., and the temperature drop rate from that temperature is 10 ° C. Cool to 0 ° C at / min. Of the observed exothermic peaks, the temperature of the peak on the highest temperature side is defined as the crystallization temperature.

[Acid value of the resin]
Measured according to the method of JIS K0070. However, only the measurement solvent is changed from the mixed solvent of ethanol and ether specified in JIS K0070 to the mixed solvent of acetone and toluene (acetone: toluene = 1: 1 (volume ratio)).

[Number average molecular weight of resin]
The number average molecular weight is determined by gel permeation chromatography (GPC) by the following method.
(1) Preparation of sample solution Dissolve the sample in tetrahydrofuran at 40 ° C so that the concentration is 0.5 g / 100 mL. Subsequently, this solution is filtered using a PTFE type membrane filter “DISMIC-25JP” (manufactured by Toyo Roshi Kaisha, Ltd.) having a pore size of 0.20 μm to remove insoluble components to obtain a sample solution.
(2) Molecular weight measurement Using the following measuring device and analytical column, tetrahydrofuran is flowed as an eluent at a flow rate of 1 mL per minute, and the column is stabilized in a constant temperature bath at 40 ° C. Inject 100 μL of the sample solution into the sample and perform measurement. The molecular weight of the sample is calculated based on a calibration curve prepared in advance. The calibration curve at this time includes several types of monodisperse polystyrene (A-500 (5.0 × 10 ² ), A-1000 (1.01 × 10 ³ ), A-2500 (2.63 × 10 ³ ), A -5000 (5.97 × 10 ³ ), F-1 (1.02 × 10 ⁴ ), F-2 (1.81 × 10 ⁴ ), F-4 (3.97 × 10 ⁴ ), F-10 (9.64 × 10 ⁴ ), F -20 (1.90 × 10 ⁵ ), F-40 (4.27 × 10 ⁵ ), F-80 (7.06 × 10 ⁵ ), F-128 (1.09 × 10 ⁶ )) prepared as standard samples are used. The molecular weight is shown in parentheses.
Measuring device: HLC-8220GPC (manufactured by Tosoh Corporation)
Analytical column: TSKgel GMH _XL + TSKgel G3000H _XL (manufactured by Tosoh Corporation)

[Melting point of release agent]
Using a differential scanning calorimeter `` DSC Q20 '' (manufactured by TA Instruments Japan Co., Ltd.), 0.01 to 0.02 g of a sample was weighed into an aluminum pan, and the temperature was raised to 200 ° C. at a heating rate of 10 ° C./min. The temperature is cooled to -10 ° C at a rate of 5 ° C / min. Next, the sample is heated to 180 ° C. at a heating rate of 10 ° C./min and measured. The maximum peak temperature of the endotherm observed from the melting endotherm curve thus obtained is taken as the melting point of the release agent.

[Average particle diameter of external additive]
The average particle diameter refers to the number average particle diameter. The particle diameter (average value of major axis and minor axis) of 500 particles is measured from a scanning electron microscope (SEM) photograph, and the number average value thereof is used.

(Volume-median particle size of toner (D ₅₀ ))
Measuring machine: Coulter Multisizer II (Beckman Coulter, Inc.)
Aperture diameter: 100 μm
Analysis software: Coulter Multisizer AccuComp version 1.19 (Beckman Coulter, Inc.)
Electrolyte: Isoton II (Beckman Coulter, Inc.)
Dispersion: Emulgen 109P (polyoxyethylene lauryl ether, HLB (Griffin): 13.6) dissolved in electrolyte is adjusted to 5% by weight Dispersion condition: 10 mg of measurement sample is added to 5 mL of the dispersion. Add and disperse with ultrasonic disperser "US-1" (manufactured by SND Co., Ltd., output: 80W) for 1 minute, then add 25mL of the electrolyte, and further with ultrasonic disperser for 1 minute Disperse to prepare a sample dispersion.
Measurement conditions: The sample dispersion was added to 100 mL of the electrolyte so that the particle size of 30,000 particles could be measured in 20 seconds, and 30,000 particles were measured. Determine the median particle size (D ₅₀ ).

Resin production examples A1-A2, A5, AH1 [resins A1-A2, A5, AH1]
Raw material monomers and esterification catalyst other than trimellitic anhydride shown in Table 1 were put into a 10 L four-necked flask equipped with a nitrogen introduction tube, a dehydration tube, a stirrer, and a thermocouple. The temperature was raised and reacted for 6 hours. After further heating to 210 ° C., trimellitic anhydride was added, the mixture was reacted at normal pressure (101.3 kPa) for 1 hour, and further reacted at 40 kPa until the desired softening point was reached. -A2, A5, AH1 were obtained. Table 1 shows the physical properties of the obtained resin.

Resin Production Examples A3 to A4 [Resin A3 to A4]
The raw material monomer and esterification catalyst shown in Table 1 were placed in a 10 L four-necked flask equipped with a thermometer, a stainless steel stirring rod, a flow-down condenser, and a nitrogen inlet tube, and in a mantle heater in a nitrogen atmosphere, 180 After the temperature was raised to ° C, the temperature was raised to 220 ° C over 5 hours. Then, it reacted until it reached the softening point shown in Table 1 at 8.0 kPa, and amorphous polyesters A3 to A4 were obtained. Table 1 shows the physical properties of the obtained resin.

Resin Production Examples C1 to C6 [Resin C1 to Resin C6]
The raw material monomers shown in Table 2 and the esterification catalyst were placed in a 10-liter four-necked flask equipped with a nitrogen introduction tube, dehydration tube, stirrer and thermocouple, and from nitrogen to 130 ° C for 10 hours under a nitrogen atmosphere. The mixture was heated up and reacted at 200 ° C. and 8 kPa for 1 hour to obtain a crystalline polyester. Table 2 shows the physical properties of the obtained resin.

Examples 1-5 and Comparative Examples 1-7
100 parts by mass of a predetermined amount of binder resin shown in Table 3, colorant “REGAL 330R” (Cabot Specialty Chemicals Inc.) 5.0 parts by mass, release agent “NP-055” (Mitsui Chemicals, polypropylene wax) , Melting point: 146 ° C.) 1.0 part by mass and 1.0 part by mass of charge control agent “Bontron E-304” (manufactured by Orient Chemical Co., Ltd.) were mixed for 1 minute using a Henschel mixer and then melt kneaded under the conditions shown below did.

A co-rotating twin screw extruder “PCM-30” (manufactured by Ikegai Co., Ltd., shaft diameter 2.9 cm, shaft cross section 7.06 cm ² ) was used. Operating conditions are: barrel set temperature 100 ° C, shaft rotation speed 200r / min (shaft rotation peripheral speed 0.30m / sec), mixture supply speed 10kg / h (mixture supply rate per unit cross section of shaft 1.42kg / h)・ Cm ² ).

The obtained resin kneaded product is cooled and coarsely pulverized by a pulverizer “ROTOPLEX” (manufactured by Hosokawa Micron Co., Ltd.) to obtain a coarsely pulverized product having a volume median particle diameter of 2 mm or less using a sieve having an opening of 2 mm. It was. Using the air classifier “DS2 type” (impact plate type, manufactured by Nippon Pneumatic Co., Ltd.), adjust the pulverization pressure so that the volume median particle size (D ₅₀ ) is 8.0 μm. And pulverized. Adjust the static pressure (internal pressure) of the finely pulverized product so that the volume median particle size (D ₅₀ ) is 8.5 μm using the airflow classifier “DSX2 type” (manufactured by Nippon Pneumatic Co., Ltd.). Then, classification was performed to obtain toner particles.

  100 parts by mass of the obtained toner particles, 0.5 parts by mass of hydrophobic silica “R972” (manufactured by Nippon Aerosil Co., Ltd., hydrophobizing agent: DMDS, average particle size: 16 nm), and hydrophobic silica “RY50” (Nippon Aerosil Co., Ltd., Hydrophobizing agent: Silicone oil, average particle size: 40 nm) 1.0 part by mass using a Henschel mixer (Nihon Coke Industries Co., Ltd.) 2100 r / min (circumferential speed 29 m / sec) Was mixed for 3 minutes to obtain a toner.

Test Example 1 [low temperature fixability]
The printer “OKI MICROLINE 5400” (Oki Data Co., Ltd.), modified to take unfixed images, was filled with toner, and a 2cm square solid unfixed image was printed. Using an external fixing device modified from OKI MICROLINE 3010 (manufactured by Oki Data Co., Ltd.), increasing the fixing roll temperature from 100 ° C to 230 ° C in 5 ° C increments at a fixing roll rotation speed of 180mm / sec. However, this unfixed image was fixed at each temperature to obtain a fixed image. The image obtained at each fixing temperature is rubbed 5 times with sand eraser “ER-502R” (manufactured by Lion Corporation) with a load of 400 g, and the image density meter “Gretag SPM50” before and after rubbing. (Gretag Macbeth Co., Ltd.), the image density ratio (%) before and after rubbing ([image density after rubbing / image density before rubbing] × 100) first exceeds 85% at the minimum fixing temperature And used as an index of low-temperature fixability. The smaller the value, the better the low-temperature fixability. The results are shown in Table 3.

Test Example 2 [Heat resistant storage stability]
5 g of toner was placed in a 20 ml polypropylene container. The container containing the toner was placed in a constant temperature and humidity chamber at 60 ° C. and a relative humidity of 50%, and stored for 3 hours with the polybin lid open. The degree of aggregation of the toner after standing was measured and used as an index of heat resistant storage stability. The smaller this value, the better the heat resistant storage stability. The results are shown in Table 3.
(Degree of aggregation)
The degree of aggregation is measured using a powder tester (manufactured by Hosokawa Micron Corporation).
Overlay sieves with 150, 75, and 45 μm openings, place 5 g of toner on top, and vibrate for 60 seconds with a vibration width of 1 mm. After the vibration, the amount of toner remaining on the sieve is measured, and the degree of aggregation is calculated using the following formula.

Test Example 3 [Smudge Suppression]
A non-magnetic one-component developing device “MicroLine5400” (manufactured by Oki Data Co., Ltd.) was loaded with 50 g of toner, and an A4 size black solid image was printed in an environment of 25 ° C. and 50% relative humidity. Next, after printing 500 sheets at a printing rate of 1%, a black solid image of A4 size was printed again. Note that J paper (manufactured by Fuji Xerox Co., Ltd.) was used as the print medium. Using "Gretag SPM50" (made by Gretag Macbeth), the image density (ID1) of the central part 5cm from the bottom of the initial black solid image and the image density (ID2) of the central part 5cm from the bottom after printing 500 sheets Measurements were made to confirm the difference in image density between the two. When the difference in image density exceeded 0.4, the number of printed sheets was regarded as the evaluation result for suppressing supply scum, and when not exceeding 0.4, printing was performed 500 sheets at a time and evaluated in the same manner. The greater the number of printed sheets, the better the suppression of supply blur. The results are shown in Table 3.

From the above results, it can be seen that the toners of Examples 1 to 5 are all excellent in low-temperature fixability, heat-resistant storage stability, and blurring suppression.
In contrast, Comparative Example 1 in which no crystalline polyester is used lacks low-temperature fixability.
From Comparative Example 2 and Comparative Example 3, the difference between the glass transition point of the amorphous polyester A and the crystallization temperature of the crystalline polyester C (Tc (c) -Tg (a)) is within a predetermined range. Although the fixing property and heat-resistant storage stability are improved, in Comparative Examples 2 and 3, since amorphous polyester having a low glass transition point is used, the heat-resistant storage property and suppression of blurring are insufficient.
Comparative Example 4 using amorphous polyester having a high glass transition point lacks low-temperature fixability.
In Comparative Example 5 where the difference in SP value between the amorphous polyester A and the crystalline polyester C (SP (a) -SP (c)) is large, the suppression of blurring is insufficient.
In Comparative Example 6 in which the difference in SP value (SP (a) −SP (c)) is small, the heat resistant storage stability and the suppression of blurring are insufficient.
In Comparative Example 7 in which the difference between the glass transition temperature of the amorphous polyester A and the crystallization temperature of the crystalline polyester C (Tc (c)-Tg (a)) is small (having a negative value), Is insufficiently controlled.

  The toner of the present invention is suitably used for developing a latent image formed in electrophotography, electrostatic recording method, electrostatic printing method and the like.

Claims (7)

A pulverized toner by melt kneading method, containing amorphous polyester A and crystalline polyester C,
The amorphous polyester A is a polycondensation of an alcohol component containing an aliphatic diol having a hydroxyl group bonded to a secondary carbon atom having 3 to 5 carbon atoms and a carboxylic acid component containing an aromatic dicarboxylic acid compound. Is a thing,
The crystalline polyester C is a polycondensate of an alcohol component containing an aliphatic diol and a carboxylic acid component containing an aliphatic dicarboxylic acid compound,
The glass transition point Tg (a) [° C.] of the amorphous polyester A satisfies the following formula (I):
The solubility parameter of the amorphous polyester A is SP (a) [(cal / cm ³ ) ^1/2 ], and the solubility parameter of the crystalline polyester C is SP (c) [(cal / cm ³ ) ^1/2 ]. A toner satisfying the following formulas (II) and (III) when the crystallization temperature of the crystalline polyester C is Tc (c) [° C.].
Formula (I): 50 ≤ Tg (a) ≤ 60
Formula (II): 1.10 ≦ SP (a) −SP (c) ≦ 1.50
Formula (III): 5 ≤ Tc (c)-Tg (a) ≤ 17   The toner according to claim 1, wherein the alcohol component of the amorphous polyester A contains 1,2-propanediol.   The toner according to claim 1, wherein Tc (c) is 57 ° C. or higher.   The toner according to claim 1, further comprising amorphous polyester AH having a softening point higher by 10 ° C. or more than amorphous polyester A.   The amorphous polyester A is at least one selected from the group consisting of succinic acid substituted with an alkyl group having 8 to 20 carbon atoms and succinic acid substituted with an alkenyl group having 8 to 20 carbon atoms as a carboxylic acid component. The toner according to claim 1, comprising a succinic compound of a kind.   The toner according to claim 1, wherein the amorphous polyester A has a number average molecular weight of 4,000 or more and 10,000 or less.   The toner according to claim 1, wherein the crystalline polyester C contains an α, ω-aliphatic diol as an alcohol component.