Binder resin for toner

Abstract

To provide: a toner binder resin that is excellent in low temperature fixability, document off-set resistance and filming resistance; an electrophotographic toner; and a method for producing an electrophotographic toner.SOLUTION: The present invention provides [1] a toner binder resin that is a reaction product of an alcohol component containing a dihydric or higher alcohol, a carboxylic acid component containing a dibasic or higher carboxylic acid compound, and a silicone, wherein the silicone is a silicone having at least one selected from an amino group, a carboxy group, an epoxy group, and a carbinol group in the side chain, [2] an electrophotographic toner containing a toner binder resin described in the [1], and [3] a method for producing an electrophotographic toner including step 1 in which toner raw materials including the binder resin described in the [1] is melt-kneaded, and step 2 in which a molten mixture obtained by the step 1 is crushed and classified to obtain toner particles.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a binder resin for toner used for developing a latent image formed in an electrophotographic method, an electrostatic recording method, an electrostatic printing method, etc., an electrophotographic toner, a method for manufacturing an electrophotographic toner, and the like.

Background Art

[0002] In the field of electrophotography, with the development of electrophotographic systems, the development of electrophotographic toners corresponding to high image quality and high speed has been demanded.

[0003] Patent Document 1 describes a toner resin soluble in an organic solvent, which is obtained by using an oligomer having a polyhydroxycarboxylic acid skeleton obtained from a diol having an aromatic ring and a hydroxycarboxylic acid and a soft segment as materials and subjecting them to an elongation reaction using an extender. Further, a toner resin is described in which the soft segment is composed of an aliphatic ester, an aliphatic ether, an aliphatic silicone, or an aliphatic linear diol having 5 or more carbon atoms, and the soft segment is polycaprolactone, poly(tetramethylene oxide) glycol, or a carbinol-modified silicone at both ends. According to the toner, it is described that excellent low-temperature fixability is ensured while ensuring heat-resistant storage stability, and good charging stability in long-term stirring and charging stability against changes in the use environment such as temperature and humidity.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] According to the toner of Patent Document 1, with the development of electrophotographic systems, better low-temperature fixability is required. However, when the low-temperature fixability of this toner is enhanced, the document offset resistance of the fixed image may decrease when printed materials are stacked and stored. Furthermore, when the low-temperature fixability of the toner is enhanced, the toner may adhere to the photoreceptor, resulting in a decrease in filming resistance. One embodiment of the present invention relates to a binder resin for toner, an electrophotographic toner, and a method for manufacturing an electrophotographic toner, which are excellent in low-temperature fixability, document offset resistance, and filming resistance. [Means for Solving the Problems]

[0006] One embodiment of the present invention relates to the following [1] to [3]. [1] A reaction product of an alcohol component containing a dihydric or higher alcohol, a carboxylic acid component containing a dicarboxylic acid compound or higher, and silicone, wherein the silicone is a silicone having at least one selected from an amino group, a carboxy group, an epoxy group, and a carbinol group in a side chain, a binder resin for toner. [2] An electrophotographic toner containing the binder resin for toner according to [1]. [3] Step 1: A step of melt-kneading a toner raw material containing the binder resin according to [1], and Step 2: A step of pulverizing and classifying the melt-kneaded product obtained in Step 1 to obtain toner particles A method for manufacturing an electrophotographic toner, including. [Advantages of the Invention]

[0007] According to one embodiment of the present invention, it is possible to provide a binder resin for toner, an electrophotographic toner, and a method for manufacturing an electrophotographic toner, which are excellent in low-temperature fixability, document offset resistance, and filming resistance. [Embodiments for Carrying Out the Invention]

[0008] [Binder Resin for Toner] The binder resin for toner according to one embodiment of the present invention (hereinafter, also simply referred to as "resin (A)") is a reaction product of an alcohol component containing a dihydric or higher alcohol, a carboxylic acid component containing a dicarboxylic acid compound or higher, and silicone. And The silicone is a silicone having at least one selected from an amino group, a carboxy group, an epoxy group, and a carbinol group in a side chain. According to the present invention, it is possible to provide a binder resin for toner, an electrophotographic toner, and a method for producing an electrophotographic toner, which are excellent in low-temperature fixability, resistance to document offset, and antifilming properties.

[0009] Generally, since silicone has poor dispersibility in a resin, even if it is added to toner, low-temperature fixability cannot be improved. On the other hand, a reaction product of an alcohol component, a carboxylic acid component, and silicone has good dispersibility of silicone, so that both low-temperature fixability and resistance to document offset can be achieved. A graft-type silicone having a functional group in a side chain has a larger number of functional groups in structure than a silicone having a functional group at both ends or one end, so that its reactivity is good, the amount of unreacted silicone in the system is reduced, and it is considered that resistance to document offset and antifilming properties are improved.

[0010] Definitions of various terms in this specification are shown below. In the specification, the carboxylic acid compound includes not only the carboxylic acid itself but also an anhydride that decomposes to generate an acid during the reaction and an alkyl ester (alkyl group having 1 to 3 carbon atoms) of each carboxylic acid. Bisphenol A is 2,2-bis(4-hydroxyphenyl)propane. In the specification, the term "binder resin composition" simply means the resin component contained in the toner containing resin (A) and resin (B).

[0011] 〔Resin (A)〕 The reactant in the resin (A) is a reaction product of an alcohol component containing a dihydric or higher alcohol, a carboxylic acid component containing a dicarboxylic acid compound having two or more carbon atoms, and a predetermined silicone, from the viewpoint of obtaining an electrophotographic toner excellent in low-temperature fixability, anti-document offset property, and anti-filming property. And the silicone is a silicone having at least one selected from an amino group, a carboxy group, an epoxy group, and a carbinol group in a side chain.

[0012] (Alcohol component) The alcohol component contains a dihydric or higher alcohol. The content of the dihydric or higher alcohol is preferably 80% by mass or more, more preferably 90% by mass or more, still more preferably 95% by mass or more, and is 100% by mass or less. Examples of the dihydric or higher alcohol include diols having an aromatic group (hereinafter also referred to as "aromatic diols"), linear or branched aliphatic diols, alicyclic diols, and polyhydric alcohols having three or more valences. Among these, aromatic diols, or linear or branched aliphatic diols are preferable, and aromatic diols are more preferable.

[0013] The aromatic diol is preferably an alkylene oxide adduct of bisphenol A, and more preferably has the formula (I):

Chemical formula

[0014] As the linear or branched aliphatic diol, an aliphatic diol having a hydroxyl group bonded to a secondary carbon atom is preferable. The number of carbon atoms of the aliphatic diol having a hydroxyl group bonded to a secondary carbon atom is preferably 3 or more and 4 or less. Examples of the aliphatic diol having a hydroxyl group bonded to a secondary carbon atom include 1,2-propanediol, 1,2-butanediol, 1,3-butanediol, and 2,3-butanediol. The amount of the aliphatic diol having a hydroxyl group bonded to a secondary carbon atom in the alcohol component is preferably 70 mol% or more, more preferably 90 mol% or more, still more preferably 95 mol% or more, and 100 mol% or less, and more preferably 100 mol%.

[0015] Examples of other linear or branched aliphatic diols include ethylene glycol, 1,3-propanediol, 1,2-butanediol, 1,4-butanediol, 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, and 1,12-dodecanediol.

[0016] Examples of alicyclic diols include hydrogenated bisphenol A [2,2-bis(4-hydroxycyclohexyl)propane] and adducts of hydrogenated bisphenol A with an alkylene oxide having 2 to 4 carbon atoms (average addition mole number: 2 to 12). Examples of polyhydric alcohols having a valence of 3 or more include glycerin, pentaerythritol, trimethylolpropane, and sorbitol. These alcohol components may be used alone or in combination of two or more.

[0017] (Carboxylic acid component) The carboxylic acid component contains a polycarboxylic acid compound having a valence of 2 or more. The content of the polycarboxylic acid compound having a valence of 2 or more is preferably 80% by mass or more, more preferably 90% by mass or more, still more preferably 95% by mass or more, and 100% by mass or less. Examples of the polycarboxylic acid compound having a valence of 2 or more include aromatic dicarboxylic acid compounds, linear or branched aliphatic dicarboxylic acid compounds, alicyclic dicarboxylic acid compounds, and polycarboxylic acid compounds having a valence of 3 or more. Among these, aromatic dicarboxylic acid compounds are preferred.

[0018] Examples of the aromatic dicarboxylic acid compounds include phthalic acid, isophthalic acid, and terephthalic acid. Among these, isophthalic acid or terephthalic acid is preferred, and terephthalic acid is more preferred. The amount of the aromatic dicarboxylic acid compound is preferably 30 mol% or more, more preferably 50 mol% or more, still more preferably 80 mol% or more, still more preferably 90 mol% or more, and 100 mol% or less in the carboxylic acid component.

[0019] The carbon number of the linear or branched aliphatic dicarboxylic acid compound is preferably 2 or more, more preferably 4 or more, even more preferably 8 or more, even more preferably 10 or more, and is preferably 22 or less, more preferably 16 or less. Examples of the linear or branched aliphatic dicarboxylic acid compound include oxalic acid, malonic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, succinic acid, adipic acid, sebacic acid, dodecanedioic acid, tetradecanedioic acid, succinic acid substituted with an aliphatic hydrocarbon group having from 1 to 20 carbon atoms, or anhydrides or alkyl esters having from 1 to 3 carbon atoms. Examples of succinic acid substituted with an aliphatic hydrocarbon group having 1 to 20 carbon atoms include dodecylsuccinic acid, dodecenylsuccinic acid, and octenylsuccinic acid. Among these, succinic acid substituted with an aliphatic hydrocarbon group having from 1 to 20 carbon atoms, or an anhydride thereof, is preferred. When a linear or branched aliphatic dicarboxylic acid compound is contained, the amount of the linear or branched aliphatic dicarboxylic acid compound in the carboxylic acid component is preferably 2 mol % or more, more preferably 3 mol % or more, even more preferably 5 mol % or more, and preferably 30 mol % or less, more preferably 20 mol % or less, even more preferably 10 mol % or less.

[0020] The trivalent or higher polyvalent carboxylic acid compound is preferably a trivalent carboxylic acid, such as trimellitic acid or its anhydride, of which trimellitic acid or its anhydride is preferred. When a trivalent or higher polyvalent carboxylic acid compound is contained, the amount of the trivalent or higher polyvalent carboxylic acid compound in the carboxylic acid component is preferably 1 mol % or more, more preferably 2 mol % or more, even more preferably 5 mol % or more, even more preferably 10 mol % or more, even more preferably 15 mol % or more, even more preferably 20 mol % or more, and is preferably 35 mol % or less, more preferably 30 mol % or less. These carboxylic acid components may be used alone or in combination of two or more.

[0021] The equivalent ratio of the carboxyl groups of the carboxylic acid component to the hydroxyl groups of the alcohol component (COOH groups / OH groups) is preferably 0.7 or more, more preferably 0.8 or more, and is preferably 1.3 or less, more preferably 1.2 or less.

[0022] (silicone) The silicone used in resin (A) is a silicone having at least one group selected from an amino group, a carboxy group, an epoxy group, and a carbinol group in a side chain, from the viewpoint of obtaining an electrophotographic toner having excellent low-temperature fixing properties, document offset resistance, and filming resistance.

[0023] More specifically, the silicone is preferably represented by the formula (1): [ka] [wherein, each R is independently a hydrocarbon group having 1 to 5 carbon atoms, each R' is independently an alkylene group having 1 to 10 carbon atoms, a is 1 or 0, each X is independently a group containing an amino group, a carboxy group, an epoxy group, or a hydroxy group, and * is a bonding site], and [ka] In the formula, R is each independently a hydrocarbon group having 1 to 5 carbon atoms, and * is a bonding site.

[0024] The silicone terminal has the formula (3): [ka] In the formula, R″ is a hydrocarbon group having 1 to 10 carbon atoms, and * is a bonding site.

[0025] The number of carbon atoms of the hydrocarbon group of R is 5 or less, preferably 4 or less, more preferably 3 or less, still more preferably 2 or less, and still more preferably 1. Examples of the hydrocarbon group of R include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a tert-butyl group, and a pentyl group. Among these, a methyl group is preferable. The number of carbon atoms of the alkylene group of R' is 10 or less, preferably 8 or less, more preferably 5 or less, still more preferably 4 or less, still more preferably 3 or less, still more preferably 2 or less, and still more preferably 1. Examples of the alkylene group of R' include a methanediyl group, an ethane-1,2-diyl group, an ethane-1,1-diyl group, an n-propane-1,3-diyl group, an n-propane-1,2-diyl group, a 1,4-n-butyl group, a 1,2-tert-butyl group, and a 1,5-pentyl group. Among these, a methanediyl group is preferable. The number of carbon atoms of the hydrocarbon group of R'' is 10 or less, preferably 8 or less, more preferably 6 or less, still more preferably 4 or less, still more preferably 3 or less, still more preferably 2 or less, and still more preferably 1. Examples of the hydrocarbon group of R'' include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a tert-butyl group, a pentyl group, and a benzyl group.

[0026] X is each independently a group containing an amino group, a carboxy group, an epoxy group, or a hydroxy group. Herein, the amino group, the carboxy group, the epoxy group, or the hydroxy group are collectively referred to as a "reactive group", and a group containing a reactive group and other moieties is also referred to as a "reactive group-containing group". Therefore, X is a reactive group or a reactive group-containing group. In formula (1), when a is 1, X is a reactive group, and when a is 0, X is a reactive group-containing group.

[0027] When a is 0, X may have an ether bond, or may be a group in which one or more reactive groups are substituted on a hydrocarbon group in which some methylene groups are substituted with ether bonds. That is, X may be an aliphatic hydrocarbon group which may have an ether bond and is substituted with one or more amino groups, carboxy groups, epoxy groups, or hydroxy groups, and the total number of carbon atoms in X is preferably 10 or less, more preferably 9 or less, and preferably 1 or more, more preferably 2 or more.

[0028] The weight average molecular weight (Mw) of the silicone is preferably 600 or more, more preferably 800 or more, and even more preferably 1,000 or more, and is preferably 20,000 or less, more preferably 10,000 or less, more preferably 7,000 or less, more preferably 6,000 or less, more preferably 5,000 or less, and even more preferably 4,000 or less. The number average molecular weight (Mn) of the silicone is preferably 500 or more, more preferably 700 or more, and even more preferably 800 or more, and is preferably 10,000 or less, more preferably 5,000 or less, more preferably 4,000 or less, more preferably 3,000 or less, and even more preferably 2,000 or less.

[0029] The kinetic viscosity of the silicone is preferably 10 mm at 25°C. 2 / s or more, preferably 15 mm 2 / s or more, more preferably 20 mm 2 / s or more, and preferably 3,000 mm 2 / s or less, preferably 2,000 mm 2 / s or less, and more preferably 1,000 mm 2 / s or less, more preferably 500 mm 2 / s or less. Among these, the kinetic viscosity of the silicone having an amino group is preferably 500 mm at 25° C. 2 / s or more, preferably 1,000 mm 2 / s or more, and more preferably 1,500 mm 2 / s or more, and preferably 3,000 mm2 / s or less, more preferably 2,000 mm 2 / s or less, even more preferably 1,800 mm 2 / s or less. The kinematic viscosity of silicone is measured using a fully automatic micro kinematic viscometer (manufactured by Bisco Co., Ltd.) at 25°C.

[0030] The functional group equivalent of silicone is preferably 300 g / mol or more, more preferably 500 g / mol or more, even more preferably 1,000 g / mol or more, and still more preferably 2,000 g / mol or more, and is preferably 6,000 g / mol or less, more preferably 5,000 g / mol or less, and even more preferably 4,000 g / mol or less. Note that the functional group equivalent means the mass of silicone per mole of the functional group.

[0031] Silicone is preferably, from the viewpoint of obtaining an electrophotographic toner excellent in low-temperature fixing property, anti-document offset property, and anti-filming property, (i) silicone having an amino group in the side chain, and the mass ratio of the silicone is 1% by mass or more and 7% by mass or less based on the total amount of the alcohol component, the carboxylic acid component, and the silicone, or (ii) silicone having at least one selected from a carboxy group, an epoxy group, and a carbinol group in the side chain, and the mass ratio of the silicone is 1% by mass or more and 30% by mass or less based on the total amount of the alcohol component, the carboxylic acid component, and the silicone. Silicone is more preferably the above (i).

[0032] As the silicone, from the viewpoint of obtaining a toner having even more excellent low-temperature fixing property, anti-document offset property, and anti-filming property, silicone (a) having an amino group in the side chain (hereinafter, also simply referred to as "silicone (a)") is preferable. Silicone (a) has the following formula (1a 0 ):

Chemical formula

[0033] Note that the terminal of the silicone (a) may be a group represented by the formula (3): [Chemical formula] [In the formula, R'' and * have the same definitions as in the aforementioned formula (3).]

[0034] Examples of the silicone (a) include modified silicones having an amino group in the side chain (for example, as a commercially available product, "KF-864" (manufactured by Shin-Etsu Chemical Co., Ltd.)).

[0035] In the resin (A), the mass ratio of the silicone (a) is preferably 1% by mass or more, more preferably 2% by mass or more, still more preferably 3% by mass or more, still more preferably 4% by mass or more, and preferably 7% by mass or less, more preferably 6% by mass or less, based on the total amount of the alcohol component, the carboxylic acid component, and the silicone.

[0036] From the viewpoint of obtaining a toner excellent in low-temperature fixability, anti-document offset property, and anti-filming property, a silicone (b) having at least one selected from a carboxy group, an epoxy group, and a carbinol group in the side chain (hereinafter, also simply referred to as "silicone (b)") is preferable as the silicone. More specifically, the silicone (b) is preferably represented by the formula (1b):

Chemical formula

Chemical formula

[0037] When the silicone (b) is a silicone having a carboxy group in the side chain, X’ is a group containing a carboxy group. It is preferable that a is 1 and X’ is a carboxy group (-COOH), and R’ is preferably an alkylene group having 1 to 10 carbon atoms, more preferably an alkylene group having 1 to 5 carbon atoms, still more preferably an alkylene group having 1 to 3 carbon atoms. Also, when silicone (b) is a silicone having a carboxy group in the side chain and a is 0, X' may be an aliphatic hydrocarbon group containing an ether bond preferably having 1 to 10 carbon atoms and substituted with a carboxy group, more preferably an aliphatic hydrocarbon group containing an ether bond having 1 to 6 carbon atoms. Here, the aliphatic hydrocarbon group containing an ether bond means having an ether bond (-O-) between carbon-carbon bonds.

[0038] When silicone (b) is a silicone having an epoxy group in the side chain, X' is a group containing an epoxy group. When a is 1 and X' is an epoxy group, or when a is 0 and X' is an aliphatic hydrocarbon group which may contain an ether bond preferably having 1 to 10 carbon atoms and containing an epoxy group, more preferably an aliphatic hydrocarbon group which may contain an ether bond having 1 to 6 carbon atoms and containing an epoxy group.

[0039] When silicone (b) is a silicone having a hydrocarbyl group in the side chain, X' is a group containing a hydroxy group. When a is 1, X' is a hydroxy group, or when a is 0, X' is an aliphatic hydrocarbon group which may contain an ether bond preferably having 1 to 10 carbon atoms and substituted with a hydroxy group, more preferably an aliphatic hydrocarbon group which may contain an ether bond having 1 to 6 carbon atoms and substituted with a hydroxy group, and the number of hydroxy groups that X' has is 1 or more, preferably 5 or less, more preferably 4 or less, still more preferably 2 or less.

[0040] In formula (1b), the group represented by *-(R') a -X' includes, for example, the following substituents 1b-1 to 1b-9.

Chemical formula

[0041] In addition, the terminal of the silicone is represented by formula (3):

Chemical formula

[0042] Examples of the silicone (b) include modified silicones having a carboxy group in the side chain (commercially available products such as "X-22-3701E" (manufactured by Shin-Etsu Chemical Co., Ltd.), "BY16-880" (manufactured by Toray Dow Corning Co., Ltd.)), modified silicones having an epoxy group in the side chain (commercially available product: "X-22-343" (manufactured by Shin-Etsu Chemical Co., Ltd.)), and modified silicones having a hydroxy group in the side chain (commercially available product: "X-22-4039" (manufactured by Shin-Etsu Chemical Co., Ltd.)).

[0043] In the resin (A), the mass ratio of the silicone (b) is preferably 1% by mass or more, more preferably 2% by mass or more, still more preferably 3% by mass or more, still more preferably 4% by mass or more, and preferably 30% by mass or less, more preferably 20% by mass or less, still more preferably 15% by mass or less, still more preferably 10% by mass or less, still more preferably 7% by mass or less, based on the total amount of the alcohol component, carboxylic acid component, and silicone.

[0044] (Physical properties of the resin (A)) The acid value of the resin (A) is preferably 0.1 mgKOH / g or more, more preferably 0.5 mgKOH / g or more, still more preferably 1 mgKOH / g or more, and preferably 40 mgKOH / g or less, more preferably 30 mgKOH / g or less, still more preferably 20 mgKOH / g or less, still more preferably 10 mgKOH / g or less, still more preferably 5 mgKOH / g or less.

[0045] The hydroxyl value of the resin (A) is preferably 0.1 mgKOH / g or more, more preferably 10 mgKOH / g or more, still more preferably 20 mgKOH / g or more, and preferably 60 mgKOH / g or less, more preferably 50 mgKOH / g or less, still more preferably 40 mgKOH / g or less.

[0046] The softening point of resin (A) is preferably 70°C or higher, more preferably 90°C or higher, still more preferably 100°C or higher, from the viewpoint of further improving the anti-document offset property and anti-filming property, and is preferably 140°C or lower, more preferably 130°C or lower, still more preferably 125°C or lower, still more preferably 120°C or lower, still more preferably 110°C or lower, from the viewpoint of further improving the low-temperature fixing property.

[0047] The glass transition temperature of resin (A) is preferably 45°C or higher, more preferably 48°C or higher, still more preferably 50°C or higher, still more preferably 55°C or higher, from the viewpoint of further improving the anti-document offset property and anti-filming property, and is preferably 80°C or lower, more preferably 70°C or lower, still more preferably 65°C or lower, from the viewpoint of further improving the low-temperature fixing property.

[0048] The number average molecular weight of resin (A) is preferably 1,000 or higher, more preferably 1,500 or higher, still more preferably 2,000 or higher, still more preferably 2,500 or higher, from the viewpoint of excellent anti-document offset property, and is preferably 10,000 or lower, more preferably 8,000 or lower, still more preferably 6,000 or lower, still more preferably 4,000 or lower, from the viewpoint of excellent low-temperature fixing property.

[0049] The acid value, softening point, glass transition temperature, and number average molecular weight of resin (A) can be appropriately adjusted according to the types and amounts of raw material monomers used, and production conditions such as reaction temperature, reaction time, and cooling rate. Moreover, these values are determined by the methods described in the examples. When two or more kinds of reactants are used in combination, it is preferable that the values of the acid value, hydroxyl value, softening point, and glass transition temperature obtained as their mixture are respectively within the aforementioned ranges.

[0050] (Method for producing resin (A)) Resin (A) can be obtained, for example, by reacting an alcohol component, a carboxylic acid component, and silicone. In this reaction, if necessary, an esterification catalyst such as tin(II) bis(2-ethylhexanoate), dibutyltin oxide, or titanium diisopropoxybis(triethanolamineate) may be used in an amount of 0.01 parts by mass or more and 5 parts by mass or less per 100 parts by mass of the total amount of the alcohol component and the carboxylic acid component; and an esterification co-catalyst such as gallic acid (the same as 3,4,5-trihydroxybenzoic acid) may be used in an amount of 0.001 parts by mass or more and 0.5 parts by mass or less per 100 parts by mass of the total amount of the alcohol component and the carboxylic acid component for the reaction. The reaction temperature is preferably 120 °C or higher, more preferably 160 °C or higher, still more preferably 180 °C or higher, and preferably 250 °C or lower, more preferably 240 °C or lower. Note that the reaction may be carried out in an inert gas atmosphere.

[0051] From the viewpoint of further improving the low-temperature fixability and anti-document offset property of the toner, the content of resin (A) in the binder resin composition of the toner is preferably 10% by mass or more, more preferably 20% by mass or more, still more preferably 30% by mass or more, still more preferably 40% by mass or more, still more preferably 50% by mass or more, and 100% by mass or less, preferably 90% by mass or less, more preferably 80% by mass or less, still more preferably 70% by mass or less.

[0052] [Electrophotographic toner] The toner used in the present invention contains resin (A) from the viewpoint of obtaining a toner excellent in low-temperature fixability, anti-document offset property, and anti-filming property. The toner contains, for example, toner particles and external additives.

[0053] [Toner particles] The toner particles preferably contain resin (A). From the viewpoint of further improving either the low-temperature fixability or the anti-document offset property, the toner particles preferably further contain a resin (B) having a softening point different from that of resin (A) by 5 °C or more. The toner particles may also contain additives such as a release agent (wax), a charge control agent, a colorant, magnetic powder, a fluidity improver, a conductivity regulator, a reinforcing filler such as a fibrous substance, an antioxidant, an anti-aging agent, and a cleaning property improver.

[0054] [Resin (B)] Resin (B) is preferably a polyester resin which is a polycondensate of an alcohol component and a carboxylic acid component, and more preferably an amorphous polyester resin. The alcohol component and the carboxylic acid component are as exemplified above.

[0055] (Physical properties of resin (B)) The acid value of resin (B) is preferably 0.1 mgKOH / g or more, more preferably 0.5 mgKOH / g or more, still more preferably 1 mgKOH / g or more, and preferably 40 mgKOH / g or less, more preferably 35 mgKOH / g or less, still more preferably 30 mgKOH / g or less, still more preferably 23 mgKOH / g or less, still more preferably 20 mgKOH / g or less.

[0056] The hydroxyl value of resin (B) is preferably 0.1 mgKOH / g or more, more preferably 10 mgKOH / g or more, still more preferably 20 mgKOH / g or more, and preferably 60 mgKOH / g or less, more preferably 50 mgKOH / g or less, still more preferably 40 mgKOH / g or less.

[0057] The difference between the softening point of resin (B) and the softening point of resin (A) is preferably 5°C or more, more preferably 10°C or more, still more preferably 15°C or more, and preferably 60°C or less, more preferably 50°C or less, still more preferably 40°C or less. The softening point of resin (B) is preferably higher than the softening point of resin (A). The softening point of resin (B) is preferably 70°C or higher, more preferably 90°C or higher, still more preferably 100°C or higher, and even more preferably 110°C or higher from the viewpoint of further improving the anti-document offset property and anti-filming property. From the viewpoint of further improving the low-temperature fixing property, it is preferably 160°C or lower, more preferably 150°C or lower, still more preferably 140°C or lower, and even more preferably 130°C or lower.

[0058] The glass transition temperature of resin (B) is preferably 50°C or higher, more preferably 60°C or higher, and still more preferably 63°C or higher, and is preferably 80°C or lower, more preferably 75°C or lower, and still more preferably 70°C or lower.

[0059] The number average molecular weight of resin (B) is preferably 1,000 or higher, more preferably 1,500 or higher, still more preferably 2,000 or higher, and even more preferably 2,500 or higher from the viewpoint of excellent anti-hot offset property. From the viewpoint of excellent low-temperature fixing property, it is preferably 10,000 or lower, more preferably 8,000 or lower, still more preferably 6,000 or lower, and even more preferably 4,000 or lower.

[0060] The acid value, hydroxyl value, softening point, glass transition temperature, and number average molecular weight of resin (B) can be appropriately adjusted according to the types and amounts of raw material monomers used, as well as production conditions such as reaction temperature, reaction time, and cooling rate. These values are determined by the methods described in the examples. When two or more kinds of resin (B) are used in combination, it is preferable that the values of the acid value, hydroxyl value, softening point, and glass transition temperature obtained as their mixture are respectively within the above-mentioned ranges.

[0061] Resin (B) can be obtained, for example, by polycondensation of an alcohol component and a carboxylic acid component. As the polycondensation conditions, for example, the reaction conditions shown in the above-mentioned production method of resin (A) can be applied.

[0062] When containing resin (B), the mass ratio of resin (A) to resin (B) [resin (A) / resin (B)] is preferably 20 / 80 or more, more preferably 30 / 70 or more, still more preferably 40 / 60 or more, still more preferably 50 / 50 or more, and preferably 90 / 10 or less, more preferably 80 / 20 or less, from the viewpoints of improving low-temperature fixability and hot offset resistance.

[0063] When containing resin (B), the content of resin (B) is preferably 10% by mass or more, more preferably 20% by mass or more, still more preferably 30% by mass or more, and 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, still more preferably 50% by mass or less in the binder resin composition of the toner, from the viewpoints of improving low-temperature fixability and document offset resistance.

[0064] 〔Release agent (wax)〕 Examples of the release agent (wax) include hydrocarbon wax, ester wax, silicone wax, and fatty acid amide wax. Examples of the hydrocarbon wax include mineral or petroleum-based hydrocarbon waxes such as paraffin wax and Fischer-Tropsch wax; and synthetic hydrocarbon waxes such as polyolefin waxes like polyethylene wax, polypropylene wax, and polybutene wax. Examples of the ester wax include mineral or petroleum-based ester waxes such as montan wax; plant-based ester waxes such as carnauba wax, rice wax, and candelilla wax; and animal-based ester waxes such as beeswax. Examples of the fatty acid amide wax include oleic acid amide and stearic acid amide. These may be used alone or in combination of two or more. Among these, hydrocarbon wax or ester wax is preferred, and it is more preferred to use hydrocarbon wax and ester wax in combination. Also, as the ester wax, carnauba wax is preferred.

[0065] The melting point of the wax is preferably 60°C or higher, more preferably 70°C or higher, and preferably 160°C or lower, more preferably 150°C or lower, still more preferably 140°C or lower. In addition, when two or more kinds of waxes are used in combination, the melting point of each wax is preferably within the above-mentioned range. When containing wax, the content of the wax is preferably 0.1 part by mass or more, more preferably 1 part by mass or more, still more preferably 2 parts by mass or more, and preferably 20 parts by mass or less, more preferably 10 parts by mass or less, still more preferably 5 parts by mass or less with respect to 100 parts by mass of the binder resin composition. Since the resin (A) has excellent releasability, the toner may not contain wax.

[0066] 〔Charge control agent〕 The charge control agent may contain either a positive charge control agent or a negative charge control agent. Examples of the positive charge control agent 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", "Bontron N-71", "Bontron N-74", "Bontron N-79" (manufactured by Orient Chemical Industries, Ltd.), etc.; triphenylmethane dyes containing a tertiary amine in the side chain, quaternary ammonium salt compounds such as "Bontron P-51" (manufactured by Orient Chemical Industries, Ltd.), cetyltrimethylammonium bromide, "COPY CHARGE PX VP435" (manufactured by Clariant), etc.; polyamine resins such as "AFP-B" (manufactured by Orient Chemical Industries, Ltd.), etc.; imidazole derivatives such as "PLZ-2001", "PLZ-8001" (manufactured by Shikoku Kasei Kogyo Co., Ltd.), etc.; styrene-acrylic resins such as "FCA-701PT" (manufactured by Fujikura Kasei Co., Ltd.), etc.

[0067] Examples of negative charge control agents include metal-containing azo dyes such as "Vari Fast Black 3804", "Bontron S-31", "Bontron S-32", "Bontron S-34", "Bontron S-36" (manufactured by Orient Chemical Industries, Ltd.), "Eisen Spilon Black TRH", "T-77" (manufactured by Hodogaya Chemical Co., Ltd.), etc.; metal compounds of benzoic 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" (manufactured by Orient Chemical Industries, Ltd.), "TN-105" (manufactured by Hodogaya Chemical Co., Ltd.), etc.; copper phthalocyanine dyes; quaternary ammonium salts such as "COPY CHARGE NX VP434" (manufactured by Clariant), nitroimidazole derivatives, etc.; organometallic compounds, etc. Among the charge control agents, negative charge control agents are preferred, and metal compounds of salicylic acid compounds are more preferred.

[0068] 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 or less, more preferably 5 parts by mass or less, still more preferably 3 parts by mass or less, and still more preferably 2 parts by mass or less, based on 100 parts by mass of the binder resin composition. Also, from the viewpoint of improving the environmental stability of the charge amount of the toner, a positive charge control agent and a negative charge control agent may be used in combination.

[0069] The toner of the present invention may contain a charge control resin in addition to or instead of the charge control agent. Examples of the charge control resin include styrene acrylic resin, polyamine resin, phenol resin, etc. Among these, from the viewpoint of reducing the grinding pressure during grinding, suppressing the generation of fine powder amount, and improving the grinding classification yield, styrene acrylic resin or phenol resin is preferred, and a quaternary ammonium base-containing styrene acrylic copolymer or phenol resin is more preferred. Examples of the quaternary ammonium base-containing styrene acrylic copolymer include "FCA-201PS" (manufactured by Fujikura Kasei Co., Ltd.). Examples of the phenol resin include "FCA-2521NJ" and "FCA-2508N" (both manufactured by Fujikura Kasei Co., Ltd.). Examples of other styrene acrylic resins include "FCA-1001NS" (manufactured by Fujikura Kasei Co., Ltd.), which is a styrene acrylic copolymer that does not contain a quaternary ammonium base. Examples of the polyamine resin include "AFP-B" (manufactured by Orient Chemical Industries Co., Ltd.). The content of the charge control resin in the toner is preferably 3 parts by mass or more, more preferably 4 parts by mass or more, and preferably 30 parts by mass or less, more preferably 20 parts by mass or less, and still more preferably 15 parts by mass or less, based on 100 parts by mass of the binder resin composition.

[0070] [Colorant] As the colorant, all dyes, pigments, etc. used as colorants for toners can be used. Carbon black, phthalocyanine blue, permanent brown FG, brilliant fast scarlet, pigment green B, rhodamine-B base, solvent red 49, solvent red 146, solvent blue 35, quinacridone, carmine 6B, disazo yellow, etc. can be used. The toner of the present invention may be either a black toner or other color toners. For example, for yellow toners, examples include C.I. Pigment Yellow (P.Y.) 3, 12, 13, 14, 16, 17, 55, 65, 73, 74, 83, 94, 95, 97, 120, 151, 154, 167, 169, 172, 180, 181, 185 and mixed pigments thereof. For magenta toners, examples include C.I. Pigment Red (P.R.) 5, 31, 57:1, 122, 146, 147, 150, 176, 184, 185, 202, 269, C.I. Pigment Violet (P.V.) 19 and mixed pigments thereof. For cyan toners, examples include C.I. Pigment Blue (P.B.) 15:3, and mixed pigments of C.I. Pigment Blue 15:3 and C.I. Pigment Green (P.G.) 7 or C.I. Pigment Green 36. Here, the mixed pigments mentioned may be such that each pigment is used in combination during the blending of toner raw materials, or they may be pre-mixed to have the same particle size and then blended with other toner raw materials for use.

[0071] From the perspective of improving the image density of the toner, the content of the colorant is preferably 0.5 parts by mass or more, more preferably 1 part by mass or more, and preferably 40 parts by mass or less, more preferably 20 parts by mass or less, and still more preferably 10 parts by mass or less, based on 100 parts by mass of the binder resin composition.

[0072] [Method for manufacturing toner] The toner may be obtained by any known method such as a melt-kneading method, an emulsion phase inversion method, a polymerization method, an emulsion aggregation method, etc. However, from the perspectives of productivity and dispersibility of the colorant, a ground toner obtained by the melt-kneading method is preferred. In the case of a ground toner obtained by the melt-kneading method, the method for manufacturing the toner preferably Step 1: A step of melt-kneading a toner raw material containing resin (A), and Step 2: A step of pulverizing and classifying the melt-kneaded product obtained in Step 1 to obtain toner particles is included. In Step 1, for example, after uniformly mixing raw materials such as resin (A), resin (B), wax, charge control agent, and colorant using a mixer such as a Henschel mixer, melt-kneading can be performed using a closed kneader, a single-screw or twin-screw extruder, an open roll type kneader, or the like. In Step 1, preferably, the mixture containing the above toner raw materials may be melt-kneaded within a range of 80°C or higher and 160°C or lower. The melt-kneading temperature is preferably 90°C or higher, more preferably 100°C or higher, and preferably 160°C or lower, more preferably 150°C or lower. In Step 1, after melt-kneading, the melt-kneaded product may be cooled and used in the next step.

[0073] In Step 2, preferably, the melt-kneaded product obtained by melt-kneading is pulverized and classified to obtain toner particles. The pulverization and classification can be performed by known methods. Furthermore, a spheroidization step of spheroidizing the shape of the obtained toner particles using a mechanical surface modification device or a thermal surface modification device can be performed by a known method.

[0074] The volume median diameter (D 50 ) of the toner particles is preferably 2 μm or more, more preferably 3 μm or more, still more preferably 4 μm or more, and preferably 10 μm or less, more preferably 8 μm or less, still more preferably 6 μm or less, from the viewpoint of obtaining a high-quality image.

[0075] Preferably, a fluidizing agent or the like is added as an external additive to the surface of the toner particles. Examples of the external additive include fine particles of inorganic materials such as hydrophobic silica, titanium oxide, alumina, cerium oxide, and carbon black, and polymer fine particles such as polycarbonate, polymethyl methacrylate, and silicone resin. Among these, silica is preferred, and from the viewpoint of environmental stability, the silica is preferably hydrophobized silica that has been hydrophobized. The method of hydrophobization is not particularly limited, and examples of the hydrophobizing agent include hexamethyldisilazane (HMDS), dimethyldichlorosilane (DMDS), silicone oil, methyltriethoxysilane, etc. Among these, hexamethyldisilazane is preferred. The treatment amount of the hydrophobizing agent is preferably 1 mg / m 2 or more and 7 mg / m 2 or less per unit surface area of the silica particles. From the viewpoints of chargeability and prevention of damage to the photoreceptor, the average particle diameter of the external additive is preferably 3 nm or more, more preferably 5 nm or more, and preferably 300 nm or less, more preferably 200 nm or less. Further, from the viewpoints of maintaining toner fluidity and preventing burial of the external additive, it is preferable to use in combination an external additive having an average particle diameter of 5 nm or more and 45 nm or less and an external additive having an average particle diameter larger than 45 nm. When using an external additive, the addition amount of the external additive is preferably 0.5 part by mass or more, more preferably 1 part by mass or more, and preferably 5 parts by mass or less, more preferably 4 parts by mass or less, still more preferably 3 parts by mass or less, based on 100 parts by mass of the toner particles.

[0076] The toner is used for developing a latent image formed in electrophotography, electrostatic recording, electrostatographic printing, etc. The toner can be used as a one-component developer or as a two-component developer mixed with a carrier.

Examples

[0077] Hereinafter, the present invention will be specifically described by way of examples, but the present invention is not limited by these examples. The physical properties of the resin, etc. were measured by the following methods.

[0078] [Measurement method] 〔Softening point of resin〕 Using a flow tester "CFT-500D" (manufactured by Shimadzu Corporation), while heating a 1 g sample at a heating rate of 6 °C / min, a load of 1.96 MPa is applied by a plunger and extruded from a nozzle with a diameter of 1 mm and a length of 1 mm. Plot the plunger drop of the flow tester against the temperature, and take the temperature at which half of the sample has flowed out as the softening point.

[0079] [Melting Point and Glass Transition Temperature of Resin] Using a differential scanning calorimeter "Q100" (manufactured by TA Instruments Japan Co., Ltd.), weigh 0.02 g of the sample into an aluminum pan, heat it up to 200 °C, and then cool it from that temperature to 0 °C at a cooling rate of 10 °C / min. Next, heat the sample at a heating rate of 10 °C / min and measure the heat quantity. Among the observed endothermic peaks, take the temperature of the peak with the largest peak area as the maximum peak temperature of endotherm. In the case of a crystalline resin, take the peak temperature as the melting point. Also, in the case of an amorphous resin, when a peak is observed, take the temperature of the peak as the glass transition temperature. When no peak is observed but a step is observed, take the temperature at the intersection of the tangent line showing the maximum slope of the curve at the step part and the extension of the baseline on the low-temperature side of the step as the glass transition temperature.

[0080] [Acid Value and Hydroxyl Value of Resin] The acid value and hydroxyl value of the resin are measured according to the neutralization titration method described in JIS K 0070:1992. However, for the measurement of the acid value, use a mixed solvent of acetone and toluene [acetone:toluene = 1:1 (volume ratio)] as the measurement solvent. And for the measurement of the hydroxyl value, use tetrahydrofuran.

[0081] [Number-Average Molecular Weight of Resin] The molecular weight distribution is measured by gel permeation chromatography (GPC) method and the number-average molecular weight is determined by the following method. (1) Preparation of Sample Solution Dissolve the sample in tetrahydrofuran at 25 °C so that the concentration becomes 0.5 g / 100 mL. Then, filter this solution using a fluororesin filter "DISMIC-25JP" with a pore size of 0.2 μm (manufactured by Advantec Toyo Co., Ltd.) to remove insoluble components, obtaining a sample solution. (2) Molecular weight measurement Using the following measuring device and analytical column, flow tetrahydrofuran as the eluent at a flow rate of 1 mL per minute, and stabilize the column in a constant temperature bath at 40 °C. Inject 100 μL of the sample solution there and perform the measurement. The molecular weight of the sample is calculated based on a calibration curve prepared in advance. For the calibration curve at this time, several types of monodisperse polystyrenes "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 ) (all manufactured by Tosoh Corporation) are used as the standard samples. Measuring device: "HLC-8220GPC" (manufactured by Tosoh Corporation) Analytical column: "GMHXL+G3000HXL" (manufactured by Tosoh Corporation)

[0082] 〔Average particle size of external additive〕 The average particle size refers to the number average particle size, which is the number average value of the particle sizes of 500 particles measured from a scanning electron microscope (SEM) photograph of the external additive. When there are a major axis and a minor axis, the particle size of the particle refers to the major axis.

[0083] 〔Volume median particle size of toner particles〕 Using a laser diffraction / scattering particle size analyzer "Mastersizer 2000" (manufactured by Malvern), isoparaffin "Isopar L" (manufactured by ExxonMobil, viscosity at 25°C: 1 mPa·s) was added to the measurement cell, and at a concentration where the scattering intensity is 5 - 15%, with a particle refractive index of 1.58 (imaginary part: 0.1) and a dispersion medium refractive index of 1.42, the volume median diameter (D 50 ) was measured.

[0084] 〔Circularity of toner〕 Preparation of dispersion: 50 mg of toner was added to 5 mL of an aqueous solution of 5 mass% polyoxyethylene lauryl ether "Emulgen 109P" (manufactured by Kao Corporation, HLB: 13.6), and after dispersing for 1 minute with an ultrasonic disperser, 20 mL of distilled water was added, and further dispersed for 1 minute with an ultrasonic disperser to prepare a toner dispersion. Measuring device: Flow-type particle image analyzer "FPIA-3000" (manufactured by Sysmex Corporation) Objective lens: 10x Measurement mode: HPF measurement mode Number of measurements: 1000

[0085] 〔CV value of toner〕 Measuring instrument: Coulter Multisizer II (manufactured by Beckman Coulter) Aperture diameter: 50 μm Analysis software: Multisizer III version 3.51 (manufactured by Beckman Coulter) Electrolyte: Isoton II (manufactured by Beckman Coulter) Dispersion: Emulgen 109P (manufactured by Kao Corporation, polyoxyethylene lauryl ether, HLB: 13.6) was dissolved in the above electrolyte to obtain a dispersion with a concentration of 5 mass%. Dispersion conditions: 10 mg of the measurement sample was added to 5 mL of the dispersion, and dispersed for 1 minute with an ultrasonic disperser. Then, 25 mL of the electrolyte was added, and further dispersed for 1 minute with an ultrasonic disperser to prepare a sample dispersion. Measurement conditions: The sample dispersion was added to 100 mL of the electrolyte, adjusted to a concentration at which the particle sizes of 30,000 particles can be measured in 20 seconds, and then 30,000 particles were measured. The CV value (%) was calculated from the particle size distribution according to the following formula. CV value (%) = (standard deviation of particle size distribution / volume average particle size) × 100

[0086] [Evaluation method] [Low-temperature fixing property] The toner was filled into the printer "Microline (registered trademark) 5400" (manufactured by Oki Data Corporation) which was modified to be able to obtain unfixed images, and an unfixed image of a solid black image with a size of 2 cm square was printed. Using an external fixing device modified from "OKI MICROLINE 3010" (manufactured by Oki Data Corporation), while increasing the temperature of the fixing roll from 100 °C to 230 °C by 5 °C each at a rotation speed of the fixing roll of 180 mm / sec, the fixing process of this unfixed image was performed at each temperature to obtain a fixed image. The images obtained at each fixing temperature were rubbed back and forth 5 times with a sand eraser "ER-502R" (manufactured by Lion Office Equipment Co., Ltd.) with a load of 400 g. The image densities before and after rubbing were measured using an image density measuring instrument "Gretag SPM50" (manufactured by GretagMacbeth). The temperature at which the image density ratio after rubbing ([image density after rubbing / image density before rubbing] × 100) first exceeded 90% was defined as the minimum fixing temperature and used as an index for low-temperature fixing property. The smaller the value, the better the low-temperature fixing property.

[0087] [Resistance to document offset] The toner was filled into the printer "OKI MICROLINE 5400" (manufactured by Oki Data Corporation), and an unfixed solid black image was formed on the printing medium "J paper" (manufactured by Fuji Xerox Co., Ltd.) (printing area: 2 cm × 12 cm, adhesion amount: 0.5 mg / cm 2 ). Subsequently, the unfixed image was fixed on the printing medium under the conditions of 160 °C and 200 mm / sec in the fixing unit of the printer. The fixed image was overlaid with the unprinted printing medium "J paper", and left for 5 days under a load of 80 g / cm 2 under the conditions of a temperature of 80 °C and a relative humidity of 50%. The presence or absence of document offset when peeled off after 5 days was visually confirmed. The obtained results were evaluated for resistance to document offset according to the following criteria. (Evaluation criteria) A: No white spots can be confirmed on the fixed image side, and no transfer to the unprinted printing medium side can be confirmed. B: No white spots can be confirmed on the fixed image side, but transfer to the unprinted printing medium side can be seen. C: Slight white spots can be confirmed on the fixed image side, but it is at a practical usable level. D: Clear white spots can be confirmed on the fixed image side. E: Considerable white spots can be confirmed on the fixed image side.

[0088] 〔Film resistance〕 The cartridge for the printer "OKI MICROLINE 5400" (manufactured by OKI DATA CORPORATION) was filled with toner, and under the environment of 25°C and 50% relative humidity, images with a printing rate of 5% were printed 10,000 sheets under the condition of 1 page every 20 seconds intermittent. Then, a solid image of 15 cm × 15 cm was printed on the part 2 cm from the upper end of the printing medium "J paper" (manufactured by Fuji Xerox Co., Ltd.). The presence or absence of image dropout of the obtained fixed image was visually confirmed. Also, the imaging drum was taken out from the printer, and the presence or absence of photoreceptor filming was visually confirmed, and the film resistance was evaluated according to the following evaluation criteria. A: There is no image dropout and no photoreceptor filming. B: There is no image dropout, but slight photoreceptor filming has occurred. C: Image dropout has occurred and photoreceptor filming has also occurred.

[0089] [Manufacture of resin] Production Example A1 (Resin A-1) The interior of a 10 L four-necked flask equipped with a nitrogen inlet tube, a water removal tube, a stirrer, and a thermocouple was purged with nitrogen. 1413 g of a propylene oxide (2.2) adduct of bisphenol A, 4156 g of an ethylene oxide (2.2) adduct of bisphenol A, 2430 g of terephthalic acid, 374 g of silicone “KF-864” (manufactured by Shin-Etsu Chemical Co., Ltd.), and 40 g of tin(II) bis(2-ethylhexanoate) were added. While stirring under a nitrogen atmosphere, the temperature was raised to 235 °C and held at 235 °C for 6 hours. Then, the pressure inside the flask was reduced, and the reaction was carried out at 8 kPa until the desired softening point was reached to obtain Resin A-1. The physical properties are shown in Table 1.

[0090] Production Examples A2 to A3 [Resins A-2 to A-3] Resins A-2 to A-3 were obtained in the same manner as in Production Example A1 except that the raw material composition was changed as shown in Table 1. The physical properties are shown in Table 1.

[0091] Production Example A4 [Resin A-4] The interior of a 10 L four-necked flask equipped with a nitrogen inlet tube, a water removal tube, a stirrer, and a thermocouple was purged with nitrogen. 2758 g of 1,2-propanediol, 5242 g of terephthalic acid, 343 g of silicone “KF-864” (manufactured by Shin-Etsu Chemical Co., Ltd.), and 40 g of tin(II) bis(2-ethylhexanoate) were added. While stirring under a nitrogen atmosphere, the temperature was gradually raised from 180 °C to 220 °C over 6 hours. Then, the reaction was carried out at 8 kPa until the desired softening point was reached to obtain Resin A-4. The physical properties are shown in Table 1.

[0092] Production Example A5 [Resin A-5] The interior of a 10 L four-necked flask equipped with a nitrogen inlet tube, a water removal tube, a stirrer, and a thermocouple was purged with nitrogen. 1413 g of a propylene oxide (2.2) adduct of bisphenol A, 4156 g of an ethylene oxide (2.2) adduct of bisphenol A, 2430 g of terephthalic acid, 374 g of silicone “X-22-343” (manufactured by Shin-Etsu Chemical Co., Ltd.), and 40 g of tin(II) bis(2-ethylhexanoate) were added. While stirring under a nitrogen atmosphere, the temperature was raised to 235 °C and held at 235 °C for 6 hours. Then, the pressure inside the flask was reduced, and the reaction was carried out at 8 kPa until the desired softening point was reached to obtain Resin A-5. The physical properties are shown in Table 1.

[0093] Production Example A6 [Resin A-6] The interior of a 10 L four-necked flask equipped with a nitrogen inlet tube, a water removal tube, a stirrer, and a thermocouple was purged with nitrogen. 1413 g of a propylene oxide (2.2) adduct of bisphenol A, 4156 g of an ethylene oxide (2.2) adduct of bisphenol A, 2430 g of terephthalic acid, 374 g of silicone “X-22-4039” (manufactured by Shin-Etsu Chemical Co., Ltd.), and 40 g of tin(II) bis(2-ethylhexanoate) were added. While stirring under a nitrogen atmosphere, the temperature was raised to 235 °C and held at 235 °C for 6 hours. Then, the pressure inside the flask was reduced, and the reaction was carried out at 8 kPa until the desired softening point was reached to obtain Resin A-6. The physical properties are shown in Table 1.

[0094] Production Example A7 [Resin A-7] The interior of a 10 L four-necked flask equipped with a nitrogen inlet tube, a water removal tube, a stirrer, and a thermocouple was purged with nitrogen. 1413 g of a propylene oxide (2.2) adduct of bisphenol A, 4156 g of an ethylene oxide (2.2) adduct of bisphenol A, 2430 g of terephthalic acid, 374 g of silicone “X-22-3701E” (manufactured by Shin-Etsu Chemical Co., Ltd.), and 40 g of tin(II) bis(2-ethylhexanoate) were added. While stirring under a nitrogen atmosphere, the temperature was raised to 235 °C and held at 235 °C for 6 hours. Then, the pressure inside the flask was reduced, and the reaction was carried out at 8 kPa until the desired softening point was reached to obtain Resin A-7. The physical properties are shown in Table 1.

[0095] Production Example A8 [Resin A-8] The interior of a 10 L four-necked flask equipped with a nitrogen inlet tube, a water removal tube, a stirrer, and a thermocouple was purged with nitrogen, and 1413 g of a propylene oxide (2.2) adduct of bisphenol A, 4156 g of an ethylene oxide (2.2) adduct of bisphenol A, 2430 g of terephthalic acid, 374 g of silicone “BY16-880” (manufactured by Toray Dow Corning Co., Ltd.), and 40 g of tin(II) bis(2-ethylhexanoate) were added. While stirring under a nitrogen atmosphere, the temperature was raised to 235°C and held at 235°C for 6 hours. Then, the pressure inside the flask was reduced, and the reaction was carried out at 8 kPa until the desired softening point was reached to obtain Resin A-8. The physical properties are shown in Table 1.

[0096] Production Example A81 [Resin A-81] The interior of a 10 L four-necked flask equipped with a nitrogen inlet tube, a water removal tube, a stirrer, and a thermocouple was purged with nitrogen, and 70 parts by mass (5091 g) of L-lactide, 30 parts by mass (2182 g) of D-lactide, and 10 parts by mass (727 g) of bis(2-hydroxypropyl) terephthalate (BHPT) were charged. The internal temperature was gradually raised, and dehydration treatment was carried out under reduced pressure conditions. Next, the temperature was further raised under N2 purge, and after confirming that the system was homogenized visually, 24 g of tin(II) bis(2-ethylhexanoate) was added to the system to carry out a polymerization reaction. At this time, the internal temperature of the system was controlled so as not to exceed 190°C. After 2 hours of reaction time elapsed, the system was switched to the outflow line again, and unreacted lactide was removed under reduced pressure conditions to complete the polymerization reaction and obtain a resin oligomer. Thereafter, 100 parts by mass (5882 g) of the resin oligomer and 10 parts by mass (588 g) of silicone “X22-160AS” (manufactured by Shin-Etsu Chemical Co., Ltd.) were charged into the flask, and the internal temperature was gradually raised. After confirming the homogenization of the system, dehydration treatment was carried out under reduced pressure. Then, the temperature was further raised, and after adding 24 g of tin(II) bis(2-ethylhexanoate) to the system at 170°C, 9 parts by mass (529 g) of an extender [isophorone diisocyanate (IPDI)] was gradually added to carry out an extension reaction to obtain Resin A-81. The physical properties are shown in Table 1.

[0097]

Table 1-1

[0098]

Table 1-2

[0099]

Table 1-3

[0100] In the table, the various silicones used are as follows. The viscosities of the following silicones are kinematic viscosities measured at 25°C using a fully automatic micro kinematic viscometer (manufactured by Bisco Tec Co., Ltd.). KF-864: silicone "KF-864" (manufactured by Shin-Etsu Chemical Co., Ltd., silicone having an amino group in the side chain, viscosity (25°C): 1,700 mm 2 / s, functional group equivalent: 3,800 g / mol) X-22-343: silicone "X-22-343" (manufactured by Shin-Etsu Chemical Co., Ltd., silicone having an epoxy group in the side chain, viscosity (25°C): 25 mm 2 / s, functional group equivalent: 525 g / mol) X-22-4039: silicone "X-22-4039" (manufactured by Shin-Etsu Chemical Co., Ltd., silicone having a carbinol group in the side chain, viscosity (25°C): 90 mm 2 / s, hydroxyl value: 58 mg KOH / g, functional group equivalent: 966 g / mol) X-22-3701E: silicone "X-22-3701E" (manufactured by Shin-Etsu Chemical Co., Ltd., silicone having a carboxy group in the side chain, viscosity (25°C): 2,000 mm 2 / s, functional group equivalent: 4,000 g / mol) BY16-880: silicone "BY16-880" (manufactured by Toray Dow Corning Co., Ltd., silicone having a carboxy group in the side chain, viscosity (25°C): 2,500 mm 2 / s, functional group equivalent: 3,500 g / mol, carboxy: 1.3%) X-22-160AS: Polyalkylsiloxane "X-22-160AS" (manufactured by Shin-Etsu Chemical Co., Ltd., silicone with a carbinol group at the end, viscosity (25 °C): 35 mm 2 / s, functional group equivalent: 470 g / mol)

[0101] Production Example B1 [Resin B-1] The inside of a 10 L four-necked flask equipped with a nitrogen inlet tube, a water removal tube, a stirrer, and a thermocouple was purged with nitrogen. 2890 g of a propylene oxide (2.2) adduct of bisphenol A, 2684 g of an ethylene oxide (2.2) adduct of bisphenol A, 1563 g of terephthalic acid, 210 g of dodecenyl succinic anhydride, and 24 g of tin(II) bis(2-ethylhexanoate) were added. While stirring under a nitrogen atmosphere, the temperature was raised to 235 °C and held at 235 °C for 6 hours. Then, the pressure inside the flask was reduced and held at 8 kPa for 1 hour. After that, after returning to atmospheric pressure, it was cooled to 220 °C, and 653 g of trimellitic anhydride was reacted at 220 °C for 0.5 hr. Then, the pressure inside the flask was reduced, and the reaction was carried out at 20 kPa until the desired softening point was reached to obtain Resin B-1. The physical properties are shown in Table 2.

[0102] Production Example B2 [Resin B-2] The inside of a 10 L four-necked flask equipped with a nitrogen inlet tube, a water removal tube, a stirrer, and a thermocouple was purged with nitrogen. 1413 g of a propylene oxide (2.2) adduct of bisphenol A, 4156 g of an ethylene oxide (2.2) adduct of bisphenol A, 2430 g of terephthalic acid, and 40 g of tin(II) bis(2-ethylhexanoate) were added. While stirring under a nitrogen atmosphere, the temperature was raised to 235 °C and held at 235 °C for 6 hours. Then, the pressure inside the flask was reduced, and the reaction was carried out at 8 kPa until the desired softening point was reached to obtain Resin B-2. The physical properties are shown in Table 2.

[0103]

Table 2

[0104] [Manufacture of Toner] Example 1-1 [Toner 1-1] 65 parts by mass of Resin A-1, 35 parts by mass of Resin B-1, 0.2 parts by mass of a negative charge control agent “Bontron E-81” (manufactured by Orient Chemical Industries, Ltd.), and 6 parts by mass of a copper phthalocyanine pigment “ECB-301” (manufactured by Dainichi Seika Chemicals Co., Ltd.) were mixed using a Henschel mixer for 1 minute and then melt-kneaded under the conditions shown below. A continuous two-roll open mill “Neutex” (manufactured by Mitsui Mining Co., Ltd., roll outer diameter: 14 cm, effective roll length: 80 cm) was used. The operating conditions of the continuous two-roll open mill were as follows: the peripheral speed of the high-speed roll (front roll) was 75 r / min (32.97 m / min), the peripheral speed of the low-speed roll (back roll) was 50 r / min (21.98 m / min), and the roll gap at the end of the kneaded material supply port side was 0.1 mm. The temperature of the heating medium and the cooling medium inside the roll were as follows: the raw material input side of the high-speed roll was 135 °C and the kneaded material discharge side was 90 °C, and the raw material input side of the low-speed roll was 35 °C and the kneaded material discharge side was 35 °C. Also, the supply rate of the raw material mixture was 10 kg / hour, and the average residence time was about 6 minutes.

[0105] The obtained resin kneaded material was cooled, coarsely pulverized by a pulverizer “Rotoplex” (manufactured by Hosokawa Micron Corporation), and a coarsely pulverized material with a volume median diameter of 2 mm or less was obtained using a sieve with an aperture of 2 mm. The obtained coarsely pulverized material was pulverized and classified using a fluidized bed jet mill “Model 400 TFG” (manufactured by Hosokawa Micron Corporation) and a centrifugal air classifier “TTSP Separator” (manufactured by Hosokawa Micron Corporation) to obtain toner particles with a volume median diameter (D 50 ) of 5.0 μm.

[0106] 100 parts by mass of the toner particles, 0.5 parts by mass of a hydrophobic silica “R972” (manufactured by Nippon Aerosil Co., Ltd., hydrophobizing agent “DMDS”, average particle size: 16 nm), and 1.0 part by mass of a hydrophobic silica “RY-50” (manufactured by Nippon Aerosil Co., Ltd., hydrophobizing agent: silicone oil, average particle size: 40 nm) as external additives were mixed using a Henschel mixer at 3000 r / min (peripheral speed 32 m / sec) for 3 minutes to obtain Toner 1-1. The results of various evaluations are shown in Table 3.

[0107] Examples 1-2 to 1-8, Comparative Examples 1-1 to 1-2 [Toner 1-2 to 1-8, 1-81 to 1-82] Toners 1-2 to 1-8, 1-81 to 1-82 were obtained in the same manner as in Example 1-1, except that the resin was changed as shown in Table 3. The results of various evaluations are shown in Table 3.

[0108]

Table 3-1

[0109]

Table 3-2

[0110] Examples 2-1 to 2-2, 3-1 to 3-2, 4-1 to 4-6 [Toner 2-1 to 2-2, 3-1 to 3-2, 4-1 to 4-6] Toners 2-1 to 2-2, 3-1 to 3-2, 4-1 to 4-6 were obtained in the same manner as in Example 1-1, except that the charge control agent, charge control resin, colorant, and release agent were changed as shown in Table 4. The results of various evaluations are shown in Table 4. The charge control agent, colorant, and release agent used in the above examples are as follows. · Bontron E-304: Negative charge control agent (metal compound of salicylic acid compound), manufactured by Orient Chemical Industries, Ltd. · Bontron P-51: Positive charge control agent (quaternary ammonium salt compound), manufactured by Orient Chemical Industries, Ltd. · FCA-2521NJ: Charge control resin, manufactured by Fujikura Kasei Co., Ltd. · HNP-9: Paraffin wax, manufactured by Nippon Seiro Co., Ltd., melting point: 78 °C · Carnauba wax C2: Carnauba wax, manufactured by Kato Yoko Co., Ltd., melting point: 85 °C · NP055: Polypropylene wax, trade name "Mitsui Hiwax NP055", manufactured by Mitsui Chemicals, Inc., melting point: 140 °C · ECB-301: C.I. Pigment Blue 15:3 (copper phthalocyanine pigment), manufactured by Dainichi Seika Kogyo Co., Ltd. · Hansai Yellow 5GX01: C.I. Pigment Yellow 74, manufactured by Clariant Chemicals, Ltd. · Toner Yellow HG: C.I. Pigment Yellow 180, manufactured by Clariant Chemicals, Ltd. · Paliotol Yellow D1155: C.I. Pigment Yellow 185, manufactured by BASF · Permanent Carmine 3810: C.I. Pigment Red 269, manufactured by Sanyo Color & Chemical Co., Ltd. · Super Magenta R: C.I. Pigment Red 122, manufactured by Dainippon Ink and Chemicals, Inc. · ECR - 101: C.I. Pigment Red 57:1, manufactured by Dainichi Seika Kogyo Co., Ltd. · Morgan L: Carbon Black, manufactured by Cabot Japan, Ltd.

[0111]

Table 4 - 1

[0112]

Table 4 - 2

[0113] Example 5 [Toner 5] Except for using a co - rotating twin - screw extruder "PCM - 30" (manufactured by Ikegai Corporation, shaft diameter: 2.9 cm, shaft cross - sectional area: 7.06 cm 2 ) instead of the continuous two - open - roll kneader "Neodecks" for melt - kneading, toner 5 was obtained in the same manner as in Example 1 - 1. The results of various evaluations are shown in Table 5.

[0114]

Table 5

[0115] Example 6 - 1 [Toner 6 - 1] The toner particles obtained by pulverization and classification were spheroidized by changing the temperature and the input amount so as to achieve a predetermined roundness using a surface modification apparatus faculty "Model F430" (manufactured by Hosokawa Micron Corporation), and toner 6-1 was obtained in the same manner as in Example 1-1. The results of various evaluations are shown in Table 6.

[0116] Example 6-2 [Toner 6-2] The toner particles obtained by pulverization and classification were spheroidized by changing the temperature and the input amount so as to achieve a predetermined roundness using a surface modification apparatus "MR-10" (manufactured by Nippon Pneumatic Mfg. Co., Ltd.), and toner 6-2 was obtained in the same manner as in Example 1-1. The results of various evaluations are shown in Table 6.

[0117] [Table 6]

[0118] Example 7 [Toner 7] Toner 7 was obtained in the same manner as in Example 1-1, except that the external additive was changed as shown in Table 7. The results of various evaluations are shown in Table 7. The external additives used in Example 7 above are as follows. · R972: Hydrophobized silica (hydrophobizing agent: DMDS (dimethyl dichlorosilane)), manufactured by Nippon Aerosil Co., Ltd., average particle size: 16 nm · RY50: Hydrophobized silica (hydrophobizing agent: silicone oil), manufactured by Nippon Aerosil Co., Ltd., average particle size: 40 nm · X-24-9600: Spherical silica fine particles (hydrophobizing agent: HMDS (hexamethyldisilazane)), manufactured by Shin-Etsu Chemical Co., Ltd., average particle size: 80 nm · Epostar S: Melamine-formaldehyde resin, manufactured by Nippon Shokubai Co., Ltd.

[0119] [Table 7]

[0120] Examples 8-1 to 8-2 [Toners 8-1, 8-2] Except that the input amount and the rotor rotation speed were adjusted so that the toner CV value falls within a predetermined range in the pulverization and classification process, toners 8-1 to 8-2 were obtained in the same manner as in Example 1-1. The results of various evaluations are shown in Table 8.

[0121]

Table 8

[0122] From the results of the examples and comparative examples above, it can be seen that according to the present invention, toners excellent in low-temperature fixability, resistance to document offset, and resistance to filming can be obtained.

Claims

1. A binder resin for toner, which is a reaction product of an alcohol component containing a dihydric or higher alcohol, a carboxylic acid component containing a dicarboxylic acid compound having two or more carbon atoms, and silicone, wherein the silicone is (i) a silicone having an amino group in its side chain, and the mass ratio of the silicone is 1% by mass or more and 7% by mass or less based on the total amount of the alcohol component, the carboxylic acid component, and the silicone, or (ii) a silicone having at least one selected from the group consisting of a carboxy group, an epoxy group, and a carbinol group in its side chain, and the mass ratio of the silicone is 1% by mass or more and 30% by mass or less based on the total amount of the alcohol component, the carboxylic acid component, and the silicone, the silicone is represented by the formula (1): 【Chemical 1】 [In the formula, each R is independently a hydrocarbon group having 1 to 5 carbon atoms, each R' is independently an alkylene group having 1 to 10 carbon atoms, a is 1 or 0, X is independently a group containing an amino group, a carboxy group, an epoxy group, or a hydroxy group, and * is a bonding site.] and a repeating unit represented by the formula (2): [Chemical Formula 2] [In the formula, each R is independently a hydrocarbon group having 1 to 5 carbon atoms, and * is a bonding site.] and has a repeating unit represented by the formula (2), the terminal of the silicone contains a group represented by the following formula (3), the alcohol component contains 70 mol% or more of an alkylene oxide adduct of bisphenol A, a binder resin for toner. 【Chemical Formula 3】 [In the formula, R'' is a hydrocarbon group having 1 to 10 carbon atoms, and * is a bonding site.]

2. The binder resin for toner according to claim 1, wherein the number average molecular weight of the binder resin for toner is 1,000 or more and 10,000 or less.

3. The binder resin for toner according to claim 1 or 2, wherein the mass ratio of the silicone is 4% by mass or more and 7% by mass or less based on the total amount of the alcohol component, the carboxylic acid component, and the silicone.

4. An electrophotographic toner containing the binder resin for toner according to any one of claims 1 to 3.

5. Step 1: A step of melt-kneading a toner raw material containing the binder resin according to any one of claims 1 to 3, and Step 2: A step of pulverizing and classifying the melt-kneaded product obtained in Step 1 to obtain toner particles A method for producing an electrophotographic toner, comprising:

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