JP2008145712A - Electrophotographic toner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide electrophotographic toner giving stable image density even at high temperature and high humidity and showing excellent low temperature fixing property and offset resistance, and to provide a method for manufacturing the toner. <P>SOLUTION: The electrophotographic toner contains a binder resin including polyester and is obtained by a melt pulverizing method, wherein the polyester has a structural unit derived from a carboxylic acid component containing at least two kinds of alkylsuccinic acids having a 9-14C alkyl group with a branched chain and/or at least two kinds of alkenylsuccinic acids having a 9-14C alkenyl group with a branched chain. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an electrophotographic toner used in electrophotography, electrostatic recording method, electrostatic printing method and the like.

In recent years, from the pursuit of high image quality, development of a small particle size toner excellent in fixability has been desired. As the binder resin used for the toner, styrene-acrylic resin, polyester, and the like are known, but polyester is used because of its excellent durability and fixability. As a toner using such a polyester, in particular, from the viewpoint of fixability, a toner by a melt-kneading pulverization method using a polyester containing an alkyl succinic acid or alkenyl succinic acid having 10 or more carbon atoms as a carboxylic acid component as a binder resin is used. (Patent Document 1 and Patent Document 2).
However, the above toner has not been sufficient from the viewpoints of image stability under high temperature and high humidity, low temperature fixability, offset resistance and the like.

JP-A-57-109825 JP 2000-35695 A

  The present invention provides an electrophotographic toner capable of obtaining a stable image density under high temperature and high humidity, and having excellent low-temperature fixability and offset resistance, and a method for producing the same.

The present invention
(1) An electrophotographic toner containing a binder resin containing polyester and obtained by a melt pulverization method, wherein the polyester is at least an alkyl succinic acid having a branched chain alkyl group having 9 to 14 carbon atoms. An electrophotographic toner having a constitutional unit derived from a carboxylic acid component containing at least two kinds of alkenyl succinic acid having two and / or branched chain alkenyl groups having 9 to 14 carbon atoms;

(2) A method for producing an electrophotographic toner comprising at least a step of melt-kneading a binder resin containing polyester, and a step of pulverizing the obtained kneaded product, wherein the polyester has a branched chain carbon number. A structural unit derived from a carboxylic acid component containing at least two kinds of alkyl succinic acids having 9 to 14 alkyl groups and / or at least two kinds of alkenyl succinic acids having a branched chain alkenyl group having 9 to 14 carbon atoms And (3) an electrophotographic toner obtained by the production method of (2) above,
About.

  According to the production method of the present invention, a stable image density can be obtained even under high temperature and high humidity, and an electrophotographic toner excellent in low temperature fixability and hot offset resistance can be provided.

Electrophotographic Toner The electrophotographic toner of the present invention is a toner for electrophotography containing a binder resin containing polyester and obtained by a melt pulverization method, wherein the polyester has 9 to 14 carbon atoms having a branched chain. Having a structural unit derived from a carboxylic acid component containing at least two kinds of alkyl succinic acid having an alkyl group and / or at least two kinds of alkenyl succinic acid having a C 9-14 alkenyl group having a branched chain It is.

[Binder resin containing polyester]
It contains at least two kinds of alkyl succinic acid having a C 9-14 alkyl group having a branched chain and / or at least two kinds of alkenyl succinic acid having a C 9-14 alkenyl group having a branched chain. Polyesters obtained by polycondensation of a carboxylic acid component and an alcohol component are excellent in low temperature fixability, hot offset resistance, and stability of image density under high temperature and high humidity.
In the present invention, the steric hindrance near the ester bond is increased by containing an alkyl succinic acid and / or alkenyl succinic acid composed of various structural isomers in terms of molecular structure as the monomer of the carboxylic acid component. As a result, the hydrophobicity of the resin increases, and a stable image density can be obtained even under high temperature and high humidity. Further, by having an alkyl distribution, the molecular weight distribution of the polyester is widened, and a low molecular weight component effective for low-temperature fixing and a high molecular weight component effective for hot offset can be simultaneously contained in the polymer.

  From the viewpoint of the hydrophobicity and molecular weight distribution of the resin, the alkyl succinic acid is composed of at least two types of alkyl succinic acid having a branched chain alkyl group having 9 to 14 carbon atoms, and the alkenyl succinic acid is a carbon having a branched chain. It consists of at least two, preferably at least three, alkenyl succinic acids having several 9 to 14 alkenyl groups. Specific examples of the alkyl group or alkenyl group having 9 to 14 carbon atoms having a branched chain include isododecenyl group and isododecyl group. By using such a carboxylic acid component containing an alkyl succinic acid having an alkyl group having a different carbon number and / or an alkenyl succinic acid having an alkenyl group having a different carbon number, the molecular weight of the resulting polyester is expanded, and the polyester For example, since the endothermic peak in the vicinity of the glass transition point in differential scanning calorimetry (DSC) is broad, the toner containing toner exhibits an effect of having a very wide fixing region, and has a conflict between low-temperature fixing and offset resistance. It has the surprising effect of being able to achieve both properties.

From the viewpoint of the hydrophobicity and molecular weight distribution of the resin, alkyl succinic acid contains a structural isomer of alkyl succinic acid derived from an alkyl group having a branched chain having 9 to 14 carbon atoms, and alkenyl succinic acid has 9 carbon atoms. It is preferable to contain a structural isomer of alkenyl succinic acid derived from an alkenyl group having -14 branched chains, and the alkyl succinic acid and / or alkenyl succinic acid preferably contains 20 or more structural isomers. Preferably it contains 25 or more, more preferably 30 or more.
In the present invention, the structural isomers of alkyl succinic acid and alkenyl succinic acid derived from the above alkyl group or alkenyl group are treated as different alkyl succinic acids or alkenyl succinic acids.

  From the viewpoint of the hydrophobicity and molecular weight distribution of the resin, the alkyl succinic acid and / or alkenyl succinic acid is preferably obtained from a compound having an alkylene group (an alkylene compound) and maleic acid and / or fumaric acid. More preferably, it is obtained from an alkylene compound and maleic acid. As the alkylene compound, those having 9 to 14 carbon atoms are preferable. Specifically, alkylene compounds obtained from ethylene, propylene, isobutylene, normal butylene and the like, for example, trimers and tetramers such as ethylene, propylene, isobutylene and normal butylene, etc. Etc. are preferably used. In addition, in the gas chromatography mass spectrometry, the alkylene compound preferably has 20 or more peaks corresponding to the alkylene compound having 9 to 14 carbon atoms, more preferably 25 or more, and even more preferably 30 under the measurement conditions described later. Have more.

  These peaks observed in gas chromatography mass spectrometry are considered to be derived from structural isomers of alkylene compounds. Alkyl succinic acid and alkenyl succinic acid produced from raw materials of alkylene compounds having a certain number of structural isomers. Is also recognized to have similar structural isomers. Polyesters obtained from alkyl succinic acid and / or alkenyl succinic acid having a certain number or more of this structural isomer have extremely high steric hindrance and are therefore highly hydrophobic. A toner containing this polyester can be used under high temperature and high humidity. The image density stability is further improved. Moreover, since the molecular weight distribution of the obtained resin is expanded by containing a plurality of types of isomers, the low-temperature fixability and the hot offset resistance are further improved. In addition, from the viewpoint of the object of the present invention, it is preferable that the number of peaks is large, but the upper limit is naturally limited due to limitations of mathematical combinations.

  Alkyl succinic acid and / or alkenyl succinic acid can be obtained by using the ene reaction by mixing the known alkylene compound with maleic acid and / or fumaric acid and heating, but is easy to manufacture. From the viewpoint of the above, a method obtained by mixing the known alkylene compound and maleic acid and heating to utilize the ene reaction is preferable. In order to obtain an alkyl succinic acid having a C 9-14 alkyl group having a branched chain and / or an alkenyl succinic acid having a C 9-14 alkenyl group having a branched chain, any known method may be used. it can. For example, the selection of the type of raw material or catalyst of the alkylene compound used for the synthesis of the alkylene compound, the method of adjusting the reaction rate, reaction time, reaction pressure, solvent, etc. Any of the methods for adjusting the distillation conditions can be used (see JP-A-48-23405, JP-A-48-23404, US Pat. No. 3,374,285, etc.).

Suitable raw materials used for the synthesis of the alkylene compound include propylene and isobutylene which are alkylene compounds having a branched chain, and propylene having a small molecular weight is more preferable from the viewpoint of increasing the number of structural isomers.
Suitable catalysts used for the synthesis of the alkylene compound include liquid phosphoric acid, solid phosphoric acid, tungsten, boron trifluoride complex and the like. In addition, from the viewpoint of easy control of the number of structural isomers, a method of adjusting by distillation conditions (for example, temperature) after random polymerization is preferable.
The total content of alkyl succinic acid and / or alkenyl succinic acid in the carboxylic acid component, which is a raw material monomer of polyester obtained by condensation polymerization of the alcohol component and the carboxylic acid component, is the hydrophobicity of the resin, that is, the toner content. From the viewpoints of image stability under high temperature and high humidity, toner fixability, and storage stability, 3 to 50 mol% is preferable, and 4 to 45 mol% is more preferable. 5-43 mol% is still more preferable.

  In the present invention, a divalent or trivalent or higher carboxylic acid component other than alkyl succinic acid and alkenyl succinic acid can be used as the carboxylic acid component. Examples of the divalent carboxylic acid include phthalic acid, isophthalic acid, Aromatic dicarboxylic acids such as terephthalic acid; oxalic acid, malonic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, succinic acid, adipic acid, alkyl groups having 1 to 7 or more carbon atoms or carbon Examples thereof include aliphatic dicarboxylic acids such as succinic acid substituted with alkenyl groups of 2 to 7 or more; anhydrides of these acids and alkyl (C1 to C3) esters of these acids. Among these, aromatic dicarboxylic acid compounds are preferable from the viewpoints of durability, fixability, and dispersibility of the colorant. Among the aromatic dicarboxylic acid compounds, terephthalic acid and isophthalic acid are preferable from the viewpoints of chargeability and fixability.

Examples of the trivalent or higher polyvalent carboxylic acid compounds include aromatic carboxylic acids such as 1,2,4-benzenetricarboxylic acid (trimellitic acid), 2,5,7-naphthalenetricarboxylic acid, pyromellitic acid, and Derivatives such as these acid anhydrides and alkyl (C1-C3) esters are mentioned. Of these, trimellitic acid and its acid anhydride are preferred from the viewpoint of being inexpensive and easy to control the reaction.
In addition, carboxylic acid, anhydride of carboxylic acid, and alkyl ester of carboxylic acid may be collectively referred to as a carboxylic acid compound in the present specification.

  Moreover, as an alcohol component which is a raw material monomer of the polyester, polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, polyoxyethylene (2.2) -2,2-bis Alkylene oxide adducts of bisphenol A such as (4-hydroxyphenyl) propane, ethylene glycol, 1,2-propylene glycol, 1,3-propanediol, 1,4-butanediol, 2,3-butanediol, neopentyl Examples include diols such as glycol, polyethylene glycol, polypropylene glycol, bisphenol A, and hydrogenated bisphenol A; trihydric or higher polyhydric alcohols such as sorbitol, pentaerythritol, glycerol, and trimethylolpropane. Among these, an alkylene oxide adduct of bisphenol A which is an aromatic alcohol is preferable from the viewpoint of chargeability.

The condensation polymerization of the alcohol component and the carboxylic acid component is preferably performed in the presence of an esterification catalyst. Examples of the esterification catalyst suitably used for the above polycondensation include dioctyltin oxide, dibutyltin oxide, titanium compound, tin (II) compound having no Sn-C bond, and these are each independently or 2 A combination of more than one species can be used.
As a titanium compound, the titanium compound which has a Ti-O bond is preferable, and the compound which has a C1-28 total carbon number alkoxy group, an alkenyloxy group, or an acyloxy group is more preferable.

Specific examples of titanium compounds include titanium diisopropylate bistriethanolamate [Ti (C ₆ H ₁₄ O ₃ N) ₂ (C ₃ H ₇ O) ₂ ], titanium diisopropylate bisdiethanolamate [Ti (C ₄ H ₁₀ O ₂ N) ₂ (C ₃ H ₇ O) ₂ ], titanium dipentylate bistriethanolamate [Ti (C ₆ H ₁₄ O ₃ N) ₂ (C ₅ H ₁₁ O) ₂ ], titanium diety rate bis triethanolaminate _{[Ti (C 6 H 14 O 3} N) 2 (C 2 H 5 O) 2 ], titanium dihydroxy octylate bis triethanolaminate _{[Ti (C 6 H 14 O 3} N) 2 (OHC 8 H ₁₆ O) ₂ ], titanium distearate bistriethanolamate [Ti (C ₆ H ₁₄ O ₃ N) ₂ (C ₁₈ H ₃₇ O) ₂ ], titanium triisopropylate triethanolamate [Ti (C _{6 H 14 O 3 N) 1 (} C 3 ₇ O) _3], titanium monopropylate tris (triethanolaminate) _{[Ti (C 6 H 14 O 3} N) 3 (C 3 H 7 O) 1 ], and the like, titanium diisopropylate Among these Preferred are rate bistriethanolamate, titanium diisopropylate bisdiethanolamate, and titanium dipentylate bistriethanolamate, which are also commercially available, for example, from Matsumoto Trading Co., Ltd.

Specific examples of other preferred titanium compounds include tetra-n-butyl titanate [Ti (C ₄ H ₉ O) ₄ ], tetrapropyl titanate [Ti (C ₃ H ₇ O) ₄ ], tetratearyl titanate [Ti (C ₁₈ H ₃₇ O) ₄ ], tetramyristyl titanate [Ti (C ₁₄ H ₂₉ O) ₄ ], tetraoctyl titanate [Ti (C ₈ H ₁₇ O) ₄ ], dioctyl dihydroxyoctyl titanate [Ti (C ₈ H ₁₇ O) ₂ (OHC ₈ H ₁₆ O) ₂ ], dimyristyl dioctyl titanate [Ti (C ₁₄ H ₂₉ O) ₂ (C ₈ H ₁₇ O) ₂ ] and the like. Among these, tetrastearyl titanate, Tetramyristyl titanate, tetraoctyl titanate and dioctyl dihydroxy octyl titanate are preferred, such as reacting a titanium halide with the corresponding alcohol. However, it is also available as a commercial product such as Nisso.

Examples of the tin (II) compound having no Sn—C bond include a tin (II) compound having a Sn—O bond, a tin (II) compound having a Sn—X (X represents a halogen atom) bond, and the like. Preferred examples include tin (II) compounds having Sn-O bonds.
Examples of the tin (II) compound having an Sn-O bond include tin (II) oxalate, tin (II) diacetate, tin (II) dioctanoate, tin (II) dilaurate, tin (II) distearate, diolein Tin (II) carboxylate having a carboxylic acid group having 2 to 28 carbon atoms such as tin (II) acid; dioctyloxy tin (II), dilauroxy tin (II), distearoxy tin (II), dioleoxy tin (II), etc. Dialkoxytin (II) having an alkoxy group having 2 to 28 carbon atoms; tin (II) oxide; tin (II) sulfate and the like having a Sn—X (X represents a halogen atom) bond include chloride. Examples thereof include tin (II) halides such as tin (II) and tin (II) bromide. Among these, (R ¹ COO) ₂ Sn (where R ¹ is a fatty acid tin represented by an alkyl or alkenyl group 5 to 19 carbon ^{atoms) (II), (R 2} O) 2 Sn ( wherein R ² is a carbon number 6-2 Dialkoxy tin represented by alkyl represents a group or an alkenyl group) (II) and tin oxide represented by SnO (II) are preferred, (R ¹ COO) fatty tin represented by ₂ Sn (II) and Tin (II) oxide is more preferable, and tin (II) dioctanoate, tin (II) distearate and tin (II) oxide are more preferably used.
The titanium compound and tin (II) compound can be used in combination of two or more thereof.

The amount of the esterification catalyst present is preferably 0.01 to 1.0 part by weight, more preferably 0.1 to 0.6 part by weight based on 100 parts by weight of the total amount of the alcohol component and the carboxylic acid component.
The polycondensation of the alcohol component and the carboxylic acid component can be performed, for example, at a temperature of 180 to 250 ° C. in an inert gas atmosphere in the presence of the esterification catalyst.
In the present invention, at least two alkyl succinic acids having a branched chain alkyl group having 9 to 14 carbon atoms and / or at least two alkenyl succinic acids having a branched chain group having 9 to 14 carbon atoms are included. The structural unit derived from the carboxylic acid component containing the seed is preferably contained in the toner of the present invention in an amount of 1 to 30% by weight, more preferably 3 to 20%, from the viewpoint of image density stability under high temperature and high humidity. % By weight.

From the viewpoint of storage stability of the toner, the softening point of the polyester is preferably 70 to 165 ° C, and the glass transition point is preferably 50 to 85 ° C. The acid value is preferably 6 to 35 mgKOH / g. The desired softening point and acid value can be obtained by adjusting the charging ratio of alcohol and carboxylic acid, the temperature of condensation polymerization, and the reaction time.
From the viewpoint of the durability of the toner, the number average molecular weight of the polyester is preferably 1,000 to 10,000, and more preferably 2,000 to 8,000.

  In the present invention, polyester includes not only polyester but also polyester modified to such an extent that its properties are not substantially impaired. Examples of the modified polyester include grafting and blocking with phenol, urethane, epoxy and the like by the methods described in JP-A-11-133668, JP-A-10-239903, JP-A-8-20636, and the like. And a composite resin having two or more kinds of resin units including a polyester unit.

The binder resin contains the above polyester, and the content of the polyester is preferably 60% by weight or more, more preferably 70% by weight or more, and 80% by weight from the viewpoint of fixability and durability. % Or more is more preferable, and it is more preferable that it is substantially 100% by weight.
Examples of the resin other than polyester include known resins used for toner, such as styrene-acrylic copolymer, epoxy, polycarbonate, polyurethane and the like.

Furthermore, the toner obtained according to the present invention may further include a release agent, a colorant, a charge control agent, a conductivity modifier, an extender pigment, a reinforcing filler such as a fibrous substance, an antioxidant, and an anti-aging agent. Additives such as agents may be added as appropriate.
The electrophotographic toner of the present invention preferably contains a release agent from the viewpoint of offset resistance.
Release agents include polyolefin wax, paraffin wax, silicones; fatty acid amides such as oleic acid amide, erucic acid amide, ricinoleic acid amide, stearic acid amide; carnauba wax, rice wax, candelilla wax, wood wax, jojoba Plant waxes such as oil; animal waxes such as beeswax; mineral / petroleum waxes such as montan wax, ozokerite, ceresin, microcrystalline wax, Fischer-Tropsch wax, etc., which can be used alone Two or more kinds may be used in combination. The melting point of the release agent is preferably 60 to 140 ° C., more preferably 60 to 100 ° C. from the viewpoints of fixability and offset resistance.
The content of the release agent is preferably 0.5 to 10 parts by weight, more preferably 1 to 8 parts by weight with respect to 100 parts by weight of the binder resin, from the viewpoint of dispersibility in the binder resin. More preferably, it is 5 to 7 parts by weight.

  There is no restriction | limiting in particular as a coloring agent, A well-known coloring agent is mentioned, According to the objective, it can select suitably. Specifically, carbon black, chrome yellow, hansa yellow, benzidine yellow, selenium yellow, quinoline yellow, permanent orange GTR, pyrazolone orange, balkan orange, watch young red, permanent red, brilliantamine 3B, brilliantamine 6B, dupont oil Various pigments and acridines such as red, pyrazolone red, resol red, rhodamine B lake, lake red C, bengal, aniline blue, ultramarine blue, calco oil blue, methylene blue chloride, phthalocyanine blue, phthalocyanine green, malachite green oxalate , Xanthene, azo, benzoquinone, azine, anthraquinone, indico, thioindico, phthalose Nin-based, aniline black, polymethine, triphenylmethane dyes, diphenylmethane dyes, thiazine, various dyes thiazole, etc. may be used in conjunction with one or more kinds.

The volume median particle size (D ₅₀ ) of the toner of the present invention is preferably from 3 to 15 μm, more preferably from 4 to 8 μm, from the viewpoints of high image quality and productivity. 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% when calculated from the smaller particle size.
Further, the softening point of the toner is preferably 80 to 160 ° C., more preferably 80 to 150 ° C., and further preferably 90 to 140 ° C. from the viewpoint of low-temperature fixability. Moreover, 45-80 degreeC is preferable from the same viewpoint, and, as for a glass transition point, 50-70 degreeC is more preferable.
The toner of the present invention is obtained by a melt pulverization method, which will be described later.

Method for Producing Electrophotographic Toner The method for producing an electrophotographic toner of the present invention comprises at least a step of melt-kneading a binder resin containing polyester and a step of pulverizing the obtained kneaded product. The polyester is at least two kinds of alkyl succinic acids having a branched chain alkyl group having 9 to 14 carbon atoms and / or at least two kinds of alkenyl succinic acids having a branched chain alkenyl group having 9 to 14 carbon atoms. It has a structural unit derived from a carboxylic acid component containing. The polyester and the binder resin containing the polyester are the same as those described in the description of the toner. The other raw material components are also as described above.

  The electrophotographic toner of the present invention is produced by a kneading and pulverizing method. As a method for producing a toner by a kneading and pulverizing method, for example, after uniformly mixing the binder resin and a release agent, a colorant, a charge control agent, and the like used as necessary with a mixer such as a ball mill, It has a step of melt-kneading with a closed kneader, a single-screw or twin-screw extruder, etc., and a step of pulverizing this melt-kneaded product, further cooling before the pulverization, and if necessary after the pulverization It has the process of classifying. For the cooling, pulverization and classification, any of the methods usually performed in the melt pulverization method can be used.

Furthermore, a fluidity improver such as hydrophobic silica may be added as an external additive to the coarsely pulverized product in the production process or the surface of the obtained toner, if necessary. External additives include known fine particles such as silica fine particles, titanium fine particles, alumina fine particles, cerium oxide fine particles, carbon black and other inorganic fine particles, and polymer fine particles such as polycarbonate, polymethyl methacrylate and silicone resin. Can be used.
The number average particle diameter of the external additive is preferably 4 to 200 nm, more preferably 8 to 30 nm. The number average particle diameter of the external additive is determined using a scanning electron microscope or a transmission electron microscope.

The amount of the external additive is preferably 0.8 to 5.0 parts by weight, more preferably 1.0 to 5.0 parts by weight, with respect to 100 parts by weight of the toner before processing with the external additive. 5 to 3.5 parts by weight are more preferable.
As the external additive, hydrophobic silica is preferable.
The electrophotographic toner of the present invention can be used as a one-component developer or a two-component developer mixed with a carrier.

Hereinafter, the present invention will be described more specifically with reference to examples and the like. In the following examples and the like, each property value was measured and evaluated by the following method.
1. Acid value of resin Measured based on the method of JIS K0070. However, only the measurement solvent was changed to a mixed solvent of acetone and toluene (acetone: toluene = 1: 1 (volume ratio)) from a mixed solvent of ethanol and ether specified in JIS K0070.

2. 1. Softening point and glass transition point of resin (1) Softening point Using a flow tester (Shimadzu Corporation, CFT-500D), 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. And extruded from a nozzle having a diameter of 1 mm and a length of 1 mm. Plot the plunger drop amount of the flow tester against the temperature, and let the softening point be the temperature at which half the sample flowed out.
(2) Glass transition point Using a differential scanning calorimeter (DSC210, manufactured by Seiko Denshi Kogyo Co., Ltd.), 0.01 to 0.02 g of the sample was weighed into an aluminum pan, heated to 200 ° C., and the temperature decreased from that temperature. A sample cooled to 0 ° C at a rate of 10 ° C / min is heated at a rate of temperature increase of 10 ° C / min, and the maximum slope from the peak rising part to the peak apex from the peak extension line below the maximum endothermic peak temperature. Is the temperature at the intersection with the tangent line.

3. Toner particle size analyzer: Coulter Multisizer II (Beckman Coulter, Inc.)
Aperture diameter: 50 μm
Analysis software: Coulter Multisizer AccuComp version 1.19
(Manufactured by Kuman Coulter)
Electrolyte: Isoton II (Beckman Coulter, Inc.)
Dispersion: Emulgen 109P (manufactured by Kao Corporation, polyoxyethylene lauryl ether,
HLB: 13.6) is dissolved in the electrolytic solution to a concentration of 5% by weight to obtain a dispersion.
Dispersion condition: 10 mg of a measurement sample was added to 5 ml of the above dispersion, and 1 by an ultrasonic disperser.
Disperse for 25 minutes, then add 25 ml of electrolyte, and further disperse for 1 minute with an ultrasonic disperser to prepare a sample dispersion.
Measurement conditions: By adding the sample dispersion to 100 ml of the electrolyte solution, the particle size of 30,000 particles is adjusted to a concentration that can be measured in 20 seconds, and then 30,000 particles are measured and the particle size distribution is determined. Determine the volume median particle size (D ₅₀ ).

4). Melting point of mold release agent The sample was heated to 200 ° C. using a differential scanning calorimeter (Seiko Denshi Kogyo Co., Ltd., DSC210) and cooled to 0 ° C. at a cooling rate of 10 ° C./min. The maximum peak temperature of heat of fusion is taken as the melting point.

5. Analysis by mass spectrometry gas chromatography A CI ion source and the following analysis column are attached to a mass spectrometry gas chromatograph (GC / MS), and the system is started up. In addition, CI reaction gas (methane) is flowed, and tuning is performed after 24 hours from the evacuation work of the MS section.

(1) GC
Gas chromatograph: Agilent HP6890N
Analysis column: Ultra 1 manufactured by HP (column length 50 m, inner diameter 0.
2mm, film thickness 0.33μm)
GC oven temperature rising condition: Initial temperature 100 ° C. (0 min)
First stage heating rate 1 ° C / min (up to 150 ° C)
Second stage heating rate 10 ° C / min (up to 300 ° C)
Final temperature 300 ℃ (10min)
Sample injection volume: 1 μL
Inlet condition: Injection mode Split method
Split ratio 50: 1
Inlet temperature 300 ° C
Carrier gas: gas helium
Flow rate 1ml / min (constant flow mode)

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

(3) Sample preparation Propylene tetramer was dissolved in isopropyl alcohol to 5%.
(Data processing method)
For the alkene component of each carbon number in the range of C9 to C14, a mass chromatogram based on the mass number corresponding to the molecular ion is extracted, and under the condition of S / N (signal / noise ratio)> 3, Perform integration according to the integration conditions. From the detection results shown in Tables 1 to 5, the ratio of the specific alkyl chain length component is calculated by the following formula.
Ratio of specific alkyl chain length component = [(total of integrated values of specific alkyl chain length) / (total of integrated values of C9 to C14)] × 100 (%)

（４）積分条件

(4) Integration conditions

C ₉ H ₁₈

C ₁₀ H ₂₀

C ₁₁ H ₂₂ , C ₁₂ H ₂₄ and C ₁₃ H ₂₆

本発明において、炭素数９〜１４に相当するアルキレン化合物とは、ガスクロマトグラフィー質量分析において、分子イオンに対応するピークのことを言う。 C ₁₄ H ₂₈

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

Production of alkylene compound A Using propylene tetramer (trade name: light tetramer) manufactured by Nippon Oil Corporation, fractionation was carried out under heating conditions of 183 to 208 ° C. to obtain alkylene compound A. The obtained alkylene compound A had 40 peaks in gas chromatography mass spectrometry.

Production of alkylene compound B An alkylene compound B was obtained in the same manner except that the fractionation conditions in the production example of the alkylene compound A were changed to 171 to 175 ° C. The resulting alkylene compound B had 25 peaks in gas chromatography mass spectrometry.

Production of alkenyl succinic anhydride A Into a 1 L autoclave manufactured by Nitto High Pressure Co., Ltd. 542.4 g of alkylene compound A, 157.2 g of maleic anhydride, 0.4 g of Chelex-O (manufactured by Sakai Chemical Industry Co., Ltd.), butyl hydroquinone , BHQ (abbreviated) 0.1 g was charged, and pressurized nitrogen substitution (0.2 MPaG) was repeated three times. After stirring was started at 60 ° C., the temperature was raised to 230 ° C. over 1 hour and the reaction was performed for 6 hours. The pressure when the reaction temperature was reached was 0.3 MPaG. After completion of the reaction, the reaction mixture was cooled to 80 ° C., returned to normal pressure (101.3 kPa), and transferred to a 1 L four-necked flask. The temperature was raised while stirring to 180 ° C., and the remaining alkylene compound was distilled off at 1.3 kPa over 1 hour. Subsequently, after cooling to room temperature (25 ° C.), the pressure was returned to normal pressure (101.3 kPa) to obtain the target alkenyl succinic acid A (406.1 g).

Production of alkenyl succinic anhydride B An alkenyl succinic anhydride B was obtained in the same manner as in the production of alkenyl succinic anhydride A except that alkylene compound B was used in place of alkylene compound A as a raw material.
Preparation of dodecenyl succinic anhydride Dodecenyl succinic anhydride was prepared in the same manner as in the preparation of alkenyl succinic anhydride A, except that 1-dodecene having one peak was used instead of the alkylene compound A in commercial gas chromatography mass spectrometry. Obtained.

Production Examples 1 and 3-5 (Production of Resins A, C, D and E)
The raw material monomer of polyester excluding trimellitic anhydride shown in Table 6 and the esterification catalyst were put into a 5-liter four-necked flask equipped with a thermometer, a stainless steel stirring bar, a flow-down condenser and a nitrogen inlet tube, and nitrogen was added. The reaction was carried out at 230 ° C. and normal pressure (101.3 kPa) for 10 hours in a mantle heater in an atmosphere, and further reacted at 8 kPa for 1 hour. After cooling to 210 ° C. and adding trimellitic anhydride shown in Table 6, the mixture was reacted for 1 hour, and then reacted to a desired softening point at 8 kPa to obtain polyester resins A, C, D and E, respectively.

Production Example 2 (Production of Resin B)
The raw material monomer of the polyester excluding fumaric acid shown in Table 6 and the esterification catalyst were put into a 5-liter four-necked flask equipped with a thermometer, a stainless steel stirring rod, a flow-down condenser and a nitrogen inlet tube, and the atmosphere was put into a nitrogen atmosphere. Then, the reaction was carried out in a mantle heater at 230 ° C. and normal pressure (101.3 kPa) for 10 hours, and further at 8 kPa for 1 hour. After cooling to 180 ° C., fumaric acid and hydroquinone shown in Table 6 were added, and the temperature was raised to 210 ° C. over 4 hours, followed by reaction to a desired softening point at 8 kPa to obtain polyester resin B.

Production Example 6 (Production of Resin F)
The raw material monomers of polyester excluding fumaric acid and trimellitic anhydride shown in Table 6 and the esterification catalyst were placed in a 5-liter four-necked flask equipped with a thermometer, a stainless steel stirring bar, a flow-down condenser and a nitrogen inlet tube. The reaction was carried out in a mantle heater in a nitrogen atmosphere at 230 ° C. and normal pressure (101.3 kPa) for 10 hours, and further at 8 kPa for 1 hour. After cooling to 180 ° C., fumaric acid, trimellitic anhydride and hydroquinone shown in Table 6 were added, and the temperature was raised to 210 ° C. over 4 hours. Obtained.

Example 1
Resin A 100 parts by weight, carbon black “MOGUL L” (Cabot Corporation) 4 parts by weight, negative charge control agent “Bontron S-34” (Orient Chemical Industries) 1 part by weight and polypropylene wax “NP-105” (Mitsui Chemicals, melting point (140 ° C.) 1 part by weight was sufficiently mixed with a Henschel mixer, and then melt kneaded at a roll rotation speed of 200 r / min and a heating temperature in the roll of 80 ° C. using a co-rotating twin screw extruder. The obtained melt-kneaded product was cooled, coarsely pulverized, then pulverized by a jet mill, and classified to obtain a powder toner having a volume median particle size (D ₅₀ ) of 8.0 μm.

Examples 2 to 5 and Comparative Examples 1 and 2
Each toner was obtained in the same manner as in Example 1, except that the resin A was changed as shown in Table 7.

The toner obtained in each of Examples 1 to 5 and Comparative Examples 1 and 2 was evaluated for low-temperature fixability, offset resistance, and developability by the following methods. The results are shown in Table 7.

[Evaluation of low-temperature fixability and offset resistance]
The toner is mounted on the printer “Page Presto N-4” (Casio Computer Co., Ltd., fixing: contact fixing method, developing method: non-magnetic one-component developing method, developing roll diameter: 2.3 cm), and the toner adhesion amount is set to 0.3. An unfixed image was obtained by adjusting to 8 mg / cm ² . A fixing machine (fixing speed: 350 mm / s) in which the fixing machine of the contact fixing type copying machine “AR-505” (manufactured by Sharp) is improved so that fixing can be performed outside the apparatus is obtained. Then, the fixing roll was fixed by fixing the unfixed image while increasing the temperature of the fixing roll from 100 ° C. to 240 ° C. by 10 ° C.
The image obtained at each fixing temperature was pasted with “UNICEF Cellophane” (Mitsubishi Pencil Co., Ltd., width 18 mm, JISZ-1522), passed through the fixing roll of the fixing machine set to 30 ° C., and then the tape was attached. The optical reflection density before and after peeling and tape peeling was measured using a reflection densitometer “RD-915” (manufactured by Macbeth). The fixing roller temperature at which the concentration ratio between the two before and after peeling (after peeling / before peeling) first exceeded 98% was defined as the lowest fixing temperature, and the low-temperature fixing property was evaluated according to the following evaluation criteria. At the same time, the occurrence of hot offset was visually observed, and the offset resistance was evaluated according to the following evaluation criteria.

Evaluation criteria (low temperature fixability)
A: Minimum fixing temperature is less than 160 ° C. ○: Minimum fixing temperature is 160 ° C. or more and less than 170 ° C. Δ: Minimum fixing temperature is 170 ° C. or more and less than 180 ° C. ×: Minimum fixing temperature is 180 ° C. or more.

(Offset resistance)
A: Hot offset does not occur even at 240 ° C.
A: Hot offset occurs at 220 ° C. or higher and lower than 240 ° C.
Δ: Hot offset occurs at 190 ° C. or higher and lower than 220 ° C.
X: Hot offset occurs at less than 190 ° C.

[Evaluation of developability in high temperature and high humidity (H / H) environment]
As a non-magnetic one-component developing device, toner is mounted on “Page Presto N-4” (manufactured by Casio Computer Co., Ltd.) equipped with a stainless steel developing roll, and 500 images are obtained in an environment of 40 ° C. and 90%. It was. The image density of the 50th and 500th images was measured using a transmission type Macbeth densitometer “TR-927”, and H / H environmental charging stability (500th image density value / 50th image) The image density was evaluated according to the following criteria.

Evaluation standard ◎: H / H environmental charging stability 0.95 or more ○: H / H environmental charging stability 0.85 or more and less than 0.95 Δ: H / H environmental charging stability 0.7 or more and less than 0.85 × : H / H environmental charge stability less than 0.7

  The toner of the present invention can be suitably used for the production of an electrophotographic toner used in electrophotography, electrostatic recording method, electrostatic printing method and the like.

Claims (6)

  An electrophotographic toner containing a binder resin containing polyester and obtained by a melt pulverization method, wherein the polyester is at least two alkyl succinic acids having a branched chain alkyl group having 9 to 14 carbon atoms, And / or an electrophotographic toner having a structural unit derived from a carboxylic acid component containing at least two alkenyl succinic acids having a C9-14 alkenyl group having a branched chain.   An electrophotographic toner production method comprising at least a step of melt-kneading a binder resin containing polyester and a step of pulverizing the obtained kneaded product, wherein the polyester has 9 to 14 carbon atoms having a branched chain. A structural unit derived from a carboxylic acid component containing at least two types of alkyl succinic acid having an alkyl group and / or at least two types of alkenyl succinic acid having a C 9-14 alkenyl group having a branched chain, A method for producing an electrophotographic toner.   Structural isomer of alkyl succinic acid having a carboxylic acid component having a branched chain C9-14 alkyl group and / or alkenyl succinic acid having a branched chain C9-14 alkenyl group The method for producing an electrophotographic toner according to claim 2, comprising at least 20 types.   The alkyl succinic acid and / or alkenyl succinic acid is obtained from an alkylene compound and at least one selected from maleic acid and fumaric acid, and the alkylene compound has 9 to 14 carbon atoms in gas chromatography mass spectrometry. The method for producing an electrophotographic toner according to claim 2, wherein the toner has at least 20 peaks corresponding to the alkylene compound within the range.   The method for producing an electrophotographic toner according to claim 2, wherein the total content of alkyl succinic acid and alkenyl succinic acid in the carboxylic acid component is 3 to 50 mol%.   An electrophotographic toner obtained by the production method according to claim 2.