JP4027841B2 - Toner production method - Google Patents

Description

【００７８】
その結果、実施例１、２及び比較例２、３で得られたトナーは剥離することなく、十分な定着性を有していた。これに対し、比較例１で得られたトナーは、トナーの剥離が生じ、定着性が不十分であった。また、比較例２、３で得られたトナーは、上記の如く、定着性は良好であったものの、比較例２で得られたトナーは異臭がし、また比較例３では、粒度分布が広いトナーしか得られなかった。
【００７９】
さらに、オフセット発生温度に着目すると、不飽和ポリエステルを含有した実施例２のトナーは、実施例１のトナーに比べてオフセット発生温度が高いことが分かる。これは、ポリエステルとビニル系樹脂のグラフト化に起因しているものと推定される。
【００８０】
【発明の効果】
本発明によれば、異臭のない、定着性の良好な、小粒径トナーを容易に得ることができる。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing a toner used for developing a latent image formed in an electrophotographic method, an electrostatic recording method, an electrostatic printing method or the like.
[0002]
[Prior art]
In recent years, there has been a strong demand for higher image quality, and toner spheroidization and particle size reduction have been studied. As one of the methods, an emulsion polymerization aggregation method is known. This method is a method in which a resin dispersion is produced by emulsion polymerization, and a colorant dispersion or the like is mixed therewith to form aggregated particles corresponding to the toner particle diameter, thereby obtaining toner particles. However, since this method is a polymerization method that is inherently suitable for the production of a high molecular weight vinyl resin, improvement in fixability is desired.
[0003]
Therefore, a method of lowering the molecular weight by emulsion polymerization in the presence of a chain transfer agent such as mercaptan or a polyester resin with good fixability is dissolved in methylene chloride, and this is forcibly dispersed in water with a ball mill or the like. It is known to mix with a vinyl resin dispersion (see Patent Document 1). However, the former method has a problem of off-flavor due to mercaptan, and the latter method can only obtain a toner having a wide particle size distribution, and cannot achieve high image quality.
[0004]
[Patent Document 1]
JP-A-10-26842 (Claim 1)
[0005]
[Problems to be solved by the invention]
An object of the present invention is to provide a method for producing a small particle size toner having no foul odor, good fixability and sharp particle size distribution.
[0006]
[Means for Solving the Problems]
The present invention is a method for producing a toner having a step of forming aggregated particles from an aqueous resin dispersion containing a neutralized product of a vinyl resin and a polyester having an acid value of 5 to 50 mgKOH / g, the aqueous resin The present invention relates to a method for producing a toner, wherein the dispersion is a resin dispersion obtained by polymerizing a raw material monomer of the vinyl resin in the presence of a neutralized product of the polyester.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
The present invention relates to a method for producing a toner having a step of forming aggregated particles from an aqueous resin dispersion containing a neutralized product of a vinyl resin and a polyester having a specific acid value. It is characterized by using a resin dispersion obtained by polymerizing a raw material monomer of vinyl resin in the presence of a neutralized product, and thereby, a particle size distribution in which vinyl resin and polyester are efficiently mixed. However, it is possible to produce a toner having a small particle diameter that is sharp and has good fixability. In the present invention, the neutralized polyester is preferably capable of forming a self-dispersing aqueous polyester resin dispersion from the viewpoint of production stability. The self-dispersing water-based polyester resin dispersion refers to a resin dispersion containing polyester that can be self-dispersed in an aqueous solvent without using an emulsifier or the like.
[0008]
The aqueous resin dispersion used in the present invention is obtained by mixing polyester and a base material, a vinyl monomer monomer and water to obtain a dispersion containing a neutralized polyester, and then adding the vinyl resin monomer. It is preferably a resin dispersion obtained by polymerization. The polyester is dissolved in the raw material monomer of the vinyl resin, a basic substance is added to ionize the carboxyl group of the polyester, and then water is added to convert the polyester into an aqueous system. More preferred is a resin dispersion obtained by polymerizing a raw material monomer of a vinyl resin after obtaining a self-dispersing water-based polyester resin dispersion.
[0009]
The polyester is obtained using a raw material monomer composed of a known alcohol component and a known carboxylic acid component such as a carboxylic acid, a carboxylic acid anhydride, or a carboxylic acid ester. The polyester may be modified with a urethane bond, an epoxy bond or the like, but is preferably not modified.
[0010]
Examples of the alcohol component include polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane and polyoxyethylene (2.2) -2,2-bis (4-hydroxyphenyl) propane. Bisphenol A alkylene (2 to 3 carbon atoms) oxide (average added mole number 1 to 16) adduct, ethylene glycol, propylene glycol, 1,4-butanediol, 1,6-hexanediol, glycerin, pentaerythritol, tri Examples include aliphatic alcohols such as methylolpropane, hydrogenated bisphenol A, and sorbitol, or their alkylene (2 to 4 carbon) oxide (average number of added moles 1 to 16) adducts. And from the viewpoint of chargeability, alkylene (2 to 3 carbon atoms) of bisphenol A Id (average addition molar number of 1 to 16) adducts are preferable, the content thereof in the alcohol component, preferably from 50 to 100 mol%, more preferably 80 to 100 mol%.
[0011]
The carboxylic acid component includes aromatic dicarboxylic acids such as phthalic acid, isophthalic acid and terephthalic acid, alkyl groups having 1 to 20 carbon atoms such as fumaric acid, maleic acid, adipic acid, succinic acid, dodecenyl succinic acid and octenyl succinic acid. Or an aliphatic dicarboxylic acid such as succinic acid substituted with an alkenyl group having 2 to 20 carbon atoms, a trivalent or higher polyvalent carboxylic acid such as trimellitic acid, pyromellitic acid or naphthalenetricarboxylic acid, and anhydrides of these acids And alkyl (1 to 3 carbon atoms) esters of these acids.
[0012]
In the present invention, the content of the trivalent or higher valent raw material monomer is preferably 30 mol% or less, more preferably 5 mol% or less, and particularly preferably 0 mol% in all raw material monomers.
[0013]
In the present invention, the polyester preferably contains an unsaturated polyester from the viewpoint of controlling the viscoelasticity of the resin and improving the offset resistance. The content of unsaturated polyester in the polyester is preferably 1 to 30% by weight. As a compound which forms the unsaturated part of polyester, the carboxylic acid compound which has unsaturated bonds, such as fumaric acid and maleic acid, is preferable, and the content has preferable 1-30 mol% in the carboxylic acid component of all the polyesters. .
[0014]
Furthermore, the alcohol component and the carboxylic acid component may contain a monovalent alcohol or a monovalent carboxylic acid compound from the viewpoint of control of the end group and control of the molecular weight. Among them, the content is preferably 10 mol% or less.
[0015]
The acid value of the polyester is 5 to 50 mgKOH / g, preferably 5 to 30 mgKOH / g, and the hydroxyl value is preferably 5 to 70 mgKOH / g, from the viewpoint of the manufacturability and chargeability of the dispersion.
[0016]
Moreover, the softening point of polyester becomes like this. Preferably it is 80-165 degreeC, More preferably, it is 90-120 degreeC, A glass transition point becomes like this. Preferably it is 50-85 degreeC, More preferably, it is 50-70 degreeC.
[0017]
Further, the number average molecular weight of the polyester is preferably 1000 or more from the viewpoint of the cohesiveness of the resin particles during the production of the toner, and is preferably 7000 or less from the viewpoint of adjusting the viscosity in the phase inversion step during the production of the polyester resin dispersion. -5000 is more preferable.
[0018]
The basic substance is not particularly limited as long as it ionizes an ionic group, for example, a carboxyl group, and examples thereof include hydroxides such as alkali metals and alkaline earth metals, and various amines including ammonia. Then, amines such as mono-, di-, and triethylamine, which may have a hydroxyl group, are preferable. The amount of the basic substance used is not particularly limited as long as at least the acid value of the polyester can be neutralized.
[0019]
The softening point, acid value, hydroxyl value, molecular weight, etc. of the polyester can be adjusted by the type and ratio of the raw material monomers, the reaction time, the reaction temperature, and the like.
[0020]
As raw material monomers for vinyl resins, styrene or styrene derivatives such as styrene and α-methylstyrene; ethylenically unsaturated monoolefins such as ethylene, propylene and butadiene; vinyl esters such as vinyl chloride and vinyl acetate; ) Acrylic acid, methyl (meth) acrylate, n-butyl (meth) acrylate, lauryl (meth) acrylate, 2-ethylhexyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, (meth) acrylic Ethylenic monocarboxylic acids such as glycidyl acid and esters thereof; Ethylene monocarboxylic acid derivatives such as (meth) acrylonitrile and (meth) acrylamide; Ethylene dicarboxylic acids such as maleic acid; Vinyl ketones; Vinyl ethers and vinylidene halides ; N-vinyl compound S, and the like. Among them, styrene and (meth) acrylic acid and its esters (having 1 to 12 carbon atoms) preferably.
[0021]
If necessary, a compound having two or more polymerizable unsaturated bonds such as divinylbenzene can be used as a crosslinking agent.
[0022]
100-1900 weight part is preferable with respect to 100 weight part of polyester, and, as for the usage-amount of the raw material monomer of vinyl-type resin, 200-900 weight part is more preferable.
[0023]
Polyester, basic substance, vinyl-based resin raw material monomer and water can be mixed together by adding them all together, or after dissolving polyester in vinyl-based resin monomer and adding basic substance and water. Although the polyester is easily dissolved in a short time, the latter method is preferable.
[0024]
The amount of water used is preferably 100 to 5000 parts by weight, more preferably 300 to 2000 parts by weight, based on 100 parts by weight of the total amount of the vinyl-based resin raw material monomer and polyester.
[0025]
An organic solvent that can be easily mixed with water, such as alcohols, ketones and esters having 1 to 4 carbon atoms, may be added, but the addition amount is preferably 50% by weight or less, and 5% by weight or less. Preferably, it is not added.
[0026]
A dispersion is obtained by stirring the raw material monomer of vinyl resin, the neutralized product of polyester and water using a homogenizer, a pressure discharge type disperser or the like. At this time, metal soap, higher alcohol sulfate, alkyl benzene sulfonate, alkyl diphenyl ether disulfonate, dialkyl sulfosuccinate, β-naphthalene sulfonic acid formalin condensate salt, etc. are added to the water based monomer monomer and polyester. About 0.1 to 5 parts by weight may be further added to 100 parts by weight of the total neutralized product to adjust the average particle size of the particles in the dispersion.
[0027]
The raw material monomer of the vinyl resin in the obtained aqueous resin dispersion can be polymerized by heating and stirring to about 0 to 90 ° C. In the present invention, such polymerization is carried out by the presence of a hydrophobic polymerization initiator. It is preferable to carry out below. The hydrophobic polymerization initiator is preferably added when mixing with the raw material monomer of polyester and vinyl resin.
[0028]
Hydrophobic polymerization initiators include peroxides such as lauryl peroxide and benzoyl peroxide; 1,1′-azobis (cyclohexane-1-carbonitrile), 2,2′-azobis (2,4-dimethylvaleronitrile) ), Azo initiators such as 2,2′-azobis (2-methylbutyronitrile), and the like. Because of polymerization in water, the half-temperature of these initiators is preferably 90 ° C. or lower. Moreover, it is good also as a redox type | system | group by using a reducing agent together.
[0029]
The weight ratio of the vinyl resin to the polyester neutralized product (vinyl resin / polyester neutralized product) in the aqueous resin dispersion is preferably 50/50 to 95/5, and preferably 60/40 to 90/10. More preferred.
[0030]
The dispersion diameter of the resin in the aqueous resin dispersion is preferably 1 μm or less, more preferably 0.01 to 1 μm, more preferably 0.1 to 1 μm in terms of the average particle size from the viewpoint of toner particle size distribution and generation of free particles. Is particularly preferred.
[0031]
Water-based resin dispersions containing neutralized vinyl resins and polyesters are further reinforced with colorants, mold release agents, charge control agents, fluidity improvers, conductivity modifiers, extender pigments, fibrous substances, etc. You may mix | blend additives, such as a filler, antioxidant, anti-aging agent, and a cleaning property improving agent, as a raw material.
[0032]
As the colorant, all of dyes and pigments used as toner colorants can be used, and carbon black; I. Acetoacetic acid arylamide monoazo yellow pigments such as CI Pigment Yellow 1, 3, 74, 97, 98; I. C.I. Pigment Yellow 12, 13, 13, 17, etc. acetoacetic acid arylamide disazo yellow pigments; I. Pigment Yellow 93, 95 and the like polyazo yellow pigments; C.I. I. Pigment yellow 180; C.I. I. Pigment yellow 185; C.I. I. Solvent Yellow 19, 77, 79, C.I. I. Yellow dyes such as disperse yellow 164; I. CI Pigment Red 48, 49: 1, 53: 1, 57, 57: 1, 81, 122, 184, 5 and the like; C.I. I. Red dyes such as Solvent Red 49, 52, 58, 8; I. Blue dyes and pigments of copper phthalocyanine and its derivatives such as CI Pigment Blue 15: 3; I. And green pigments such as CI Pigment Green 7 and 36 (phthalocyanine green). These may be used alone or in combination of two or more. The toner produced according to the present invention is a black toner. Any of mono-color toner and full-color toner may be used. The amount of the colorant to be used is preferably 1 to 15 parts by weight with respect to 100 parts by weight of the total amount of the neutralized vinyl resin and polyester.
[0033]
Examples of the release agent include low molecular weight polyolefins such as polyethylene, polypropylene, and polybutene; silicones having a softening point upon heating; fatty acid amides such as oleic acid amide, erucic acid amide, ricinoleic acid amide, and stearic acid amide; Plant waxes such as carnauba wax, rice wax, candelilla wax, tree wax and jojoba oil; animal waxes such as beeswax; minerals such as montan wax, ozokerite, ceresin, paraffin wax, microcrystalline wax, and Fischer-Tropsch wax Petroleum wax; and modified products thereof. These may be contained alone or in admixture of two or more.
[0034]
The additive is preferably mixed in advance with a water-based resin dispersion containing a neutralized product of vinyl resin and polyester in a state of being dispersed in another dispersion medium.
[0035]
The dispersion diameter of the additive in the dispersion medium is preferably 1 μm or less, more preferably 0.01 to 1 μm in terms of the average particle diameter, from the viewpoint of toner particle size distribution and generation of free particles. For example, in the case of a mold release agent, it is dispersed in water together with a polymer electrolyte such as an ionic surfactant, polymer acid, polymer base, etc., heated above the melting point of the mold release agent, a homogenizer, a pressure discharge type disperser, etc. Can be easily made into fine particles having a size of 1 μm or less.
[0036]
Examples of the dispersion medium in which various additives are dispersed in advance include an aqueous medium. Examples of the aqueous medium include water such as distilled water and ion-exchanged water, alcohols, and the like. These may be used alone or in combination of two or more, but preferably an aqueous medium. It is preferable that 50% by weight or more, more preferably 95% by weight or more, and particularly preferably 100% of the water is water.
[0037]
Formation of the aggregated particles from the aqueous resin dispersion can be performed as follows. For example, when the water-based resin dispersion exhibits an anionic property due to the neutralized carboxyl group of polyester or the inclusion of an anionic surfactant, a cationic surfactant is mixed. The order of blending the colorant, release agent, etc. may be determined appropriately according to its ionicity, etc., but the same ionic thing as the aqueous resin dispersion is first mixed with the aqueous resin dispersion, and then It is preferable to add a contradictory ionic dispersion.
[0038]
As the surfactant, anionic surfactants such as disodium dodecyl diphenyl ether disulfonate, sodium dodecylbenzene sulfonate, sodium dodecyl sulfate; amine salt types such as alkylbenzene dimethyl ammonium chloride, alkyl trimethyl ammonium chloride, cetyl pyridinium chloride, Cationic surfactants such as quaternary ammonium salt type; nonionic surfactants such as polyethylene glycol, alkylphenol ethylene oxide adducts, polyhydric alcohols, and the like, among these, anionic surfactants, An ionic surfactant such as a cationic surfactant is preferred.
[0039]
When the aqueous resin dispersion to which an ionic surfactant that is opposite to the aqueous resin dispersion is added is stirred, the resin particles and the like are aggregated in the aqueous resin dispersion due to the interaction of the ionic surfactant, and the soft agglomerated particles Is formed. The stirring is preferably performed at a temperature not higher than the glass transition point of the resin particles contained in the aqueous resin dispersion from the viewpoint of forming aggregated particles in a more stable state. The stirring means is not particularly limited, and a known dispersion device such as a rotary shear type homogenizer, a ball mill having a media, a sand mill, a dyno mill, or the like can be used. Further, the content of the aggregated particles is preferably 40% by weight or less in the aggregated particle dispersion.
[0040]
It is preferable that the formed soft agglomerated particles are further fused to adjust the particle size by heating and stirring to facilitate separation. At this time, an aqueous resin dispersion or the like is further added and contained in the dispersion. The resin component may be fused with the soft agglomerated particles. As the heating temperature, a temperature from the glass transition point of the resin to the boiling point of water is preferable, and specifically, a temperature from the glass transition point temperature of the resin to 100 ° C. is more preferable. The stirring time is preferably about 30 minutes to 10 hours. In order to stabilize the aggregated particles, it is preferable to add an activator.
[0041]
The average particle size of the aggregated particles is preferably controlled to be approximately the same as the average particle size of the target toner. The control can be easily performed, for example, by appropriately setting / changing the balance and temperature of the ionic activators that conflict with each other and the stirring and mixing conditions.
[0042]
A toner can be obtained by separating the obtained agglomerated particles, and washing and drying as appropriate. The surface of the toner further includes inorganic particles such as silica, alumina, titania, calcium carbonate, and vinyl resins. Further, resin particles such as polyester and silicone resin may be externally added by stirring in a dry state.
[0043]
The toner obtained by the present invention can be used, for example, as it is alone as a non-magnetic one-component developer, or mixed with a carrier and used as a two-component developer.
[0044]
【Example】
[Softening point]
Using a Koka type flow tester (manufactured by Shimadzu Corporation, CFT-500D), a 1 g sample was heated at a heating rate of 6 ° C./min, a load of 1.96 MPa was applied by a plunger, a diameter of 1 mm, A nozzle with a length of 1 mm is pushed out, thereby drawing a plunger tester drop amount (flow value) -temperature curve of the flow tester. When the height of the S-curve is h, the temperature corresponding to h / 2 (resin The temperature at which half of the effluent flowed out) is taken as the softening point.
[0045]
[Glass transition point]
Using a differential scanning calorimeter (DSC210, manufactured by Seiko Denshi Kogyo Co., Ltd.), the sample was heated to 200 ° C. and cooled to 0 ° C. at a rate of temperature decrease of 10 ° C./min. The temperature at the intersection of the base line extension below the maximum peak temperature and the tangent showing the maximum slope from the peak rising portion to the peak apex is defined as the glass transition point of the resin.
[0046]
[Acid value and hydroxyl value]
Measured according to JIS K0070.
[0047]
[Average molecular weight]
The molecular weight distribution is measured by the following GPC method.
Measuring device: CO-8010 (manufactured by Tosoh Corporation)
Analysis column: GMHXL + G3000HXL (manufactured by Tosoh)
Sample concentration: 0.5 g / 100 ml tetrahydrofuran
Eluent: Tetrahydrofuran (40 ° C)
Flow rate: 1 ml / min
Standard sample: monodisperse polystyrene
[0048]
[Volume average particle diameter of resin particles in resin dispersion]
Measure with a Coulter Counter N4 (Beckman Coulter, Inc.).
[0049]
[Volume average particle diameter of toner (aggregated particles)]
Measure with Coulter Multisizer II (Beckman Coulter, Inc.).
[0050]
Production example 1 of polyester
1050 g of polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, 423 g of terephthalic acid, and 3.7 g of dibutyltin oxide were placed in a glass 2-liter four-necked flask, and a thermometer, A stainless steel stirring bar, a flow-down condenser and a nitrogen introduction tube were attached, and the mixture was reacted in a mantle heater while stirring at 235 ° C. under a nitrogen stream for 10 hours to obtain polyester A.
[0051]
The obtained resin was a pale yellow solid having a softening point of 100 ° C., a glass transition point of 63 ° C., an acid value of 9.5 mgKOH / g, and a number average molecular weight of 1,800.
[0052]
Production example 2 of polyester
1050 g of polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, 340 g of fumaric acid, and 1.5 g of hydroquinone are placed in a glass 2-liter four-necked flask, a thermometer, made of stainless steel A stirring bar, a flow-down condenser, and a nitrogen introduction tube were attached, and the reaction was carried out in a mantle heater with stirring at 210 ° C. under a nitrogen stream. The degree of polymerization was followed by the softening point measured according to ASTM D36-86, and the reaction was terminated when the softening point reached 100 ° C. to obtain polyester B.
[0053]
The obtained resin was a pale yellow solid having a softening point of 101 ° C., a glass transition point of 61 ° C., an acid value of 21.5 mgKOH / g, and a number average molecular weight of 3,500.
[0054]
Production example 1 of aqueous resin dispersion
Into a 2-liter stainless beaker, 120 parts by weight of styrene, 30 parts by weight of butyl acrylate and 5 parts by weight of 1,1′-azobis (cyclohexane-1-carbonitrile) are added, and 50 parts by weight of polyester A is added at room temperature. And dissolved. To the resulting solution, 1 part by weight of triethylamine was added for neutralization, and then 1000 parts by weight of ion-exchanged water was added. K. Using a homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), the mixture was stirred at a stirring speed of 3000 r / min for 1 hour to obtain a dispersion in which particles were dispersed with an average particle size of 0.5 μm.
[0055]
The obtained dispersion was transferred to a 2 liter reactor equipped with a stirrer, a reflux condenser, a dropping funnel, a thermometer and a nitrogen introduction tube, stirred at 85 ° C. for 5 hours, and an average particle size of 0.5 μm. An aqueous resin dispersion A was obtained.
[0056]
Production example 2 of aqueous resin dispersion
In a 2 liter stainless steel beaker, 120 parts by weight of styrene, 30 parts by weight of butyl acrylate and 5 parts by weight of lauryl peroxide were added, and 45 parts by weight of polyester A and 5 parts by weight of polyester B were added and dissolved at room temperature. . To the resulting solution, 1 part by weight of triethylamine was added for neutralization, and then 1000 parts by weight of ion-exchanged water was added. K. Using a homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), the mixture was stirred at a stirring speed of 3000 r / min for 1 hour to obtain a dispersion in which particles were dispersed with an average particle size of 0.7 μm.
[0057]
The obtained dispersion was transferred to a 2 liter reactor equipped with a stirrer, a reflux condenser, a dropping funnel, a thermometer and a nitrogen introduction tube, stirred at 70 ° C. for 5 hours, and an average particle size of 0.7 μm. An aqueous resin dispersion B was obtained.
[0058]
Production example 1 of vinyl resin dispersion
6 g of an anionic surfactant (Perex SS-L, manufactured by Kao Corporation) was dissolved in 1000 g of ion-exchanged water, heated to 80 ° C., and purged with nitrogen.
A mixture of a monomer in which 240 g of styrene and 60 g of n-butyl acrylate were mixed with a solution in which 3 g of ammonium persulfate was dissolved in 10 g of ion-exchanged water was dropped into the nitrogen-substituted solution over 90 minutes, and then left for 1 hour. The polymerization was terminated to obtain a vinyl resin dispersion A (resin content: 23% by weight (in terms of solid content)).
[0059]
The vinyl resin particles dispersed in the obtained resin dispersion had an average particle size of 85 nm, a softening point of 165 ° C., a glass transition point of 60 ° C., and a weight average molecular weight (Mw) of 100,000.
[0060]
Production example 2 of vinyl resin dispersion
6 g of an anionic surfactant (Perex SS-L, manufactured by Kao Corporation) was dissolved in 1000 g of ion-exchanged water, heated to 80 ° C. and purged with nitrogen.
A mixture of a monomer prepared by mixing 240 g of styrene, 60 g of n-butyl acrylate and 15 g of lauryl mercaptan and a solution prepared by dissolving 3 g of ammonium persulfate in 10 g of ion-exchanged water was dropped over 90 minutes, and then left for 1 hour to polymerize. After completion, a vinyl resin dispersion B (resin content: 23% by weight (in terms of solid content)) was obtained.
[0061]
The vinyl resin particles dispersed in the obtained resin dispersion had an average particle size of 90 nm, a softening point of 128 ° C., a glass transition point of 58 ° C., and a weight average molecular weight (Mw) of 30,000.
[0062]
Production example 1 of polyester resin dispersion
100 g of polyester B and 200 g of methylene chloride were mixed using a ball mill (UB32, manufactured by Yamato Scientific Co., Ltd.) to dissolve polyester B. The obtained solution was added to 300 g of pure water containing 10% polyethylene glycol and 0.7% anionic surfactant (Neopelex G-25, manufactured by Kao Corporation), and a homogenizer was used. A strong shearing force was applied to disperse the polyester. Furthermore, it heated at 60 degreeC and hold | maintained for 1 hour, and obtained polyester resin dispersion A (resin content: 17 weight% (solid content conversion)). The average particle diameter of the polyester resin particles dispersed in the obtained resin dispersion was 800 nm.
[0063]
Example of production of colorant dispersion
Carbon black (Mogal L, Cabot Corp.) 50 g, nonionic surfactant (Emulgen 150, Kao Co., Ltd.) 5 g and ion-exchanged water 200 g are mixed and dispersed using a homogenizer for 10 minutes. A colorant dispersion A dispersed with an average particle size of 250 nm was obtained.
[0064]
Example of production of mold release agent dispersion
50 g of paraffin wax (HNP0190, manufactured by Nippon Seiwa Co., Ltd., melting point: 85 ° C.), 5 g of cationic surfactant (Sanisol B50, manufactured by Kao Corporation) and 200 g of ion-exchanged water are heated to 95 ° C. and homogenizer. Then, the paraffin wax was dispersed using a pressure discharge homogenizer, and a release agent dispersion A in which the paraffin wax was dispersed with an average particle size of 550 nm was obtained.
[0065]
Example 1
A homogenizer of 600 g of aqueous resin dispersion A, 30 g of colorant dispersion A, 40 g of release agent dispersion A, and 1.5 g of a cationic surfactant (Sanisol B50, manufactured by Kao Corporation) in a round stainless steel flask Were mixed and dispersed, and then heated to 48 ° C. while stirring in the flask in a heating oil bath. Furthermore, after maintaining at 48 ° C. for 1 hour, it was confirmed that soft agglomerated particles having an average particle diameter of 7.6 μm were formed.
[0066]
After adding 3 g of an anionic surfactant (Perex SS-L, manufactured by Kao Corporation) to the dispersion in which soft agglomerated particles are formed, a reflux tube is attached to the stainless steel flask, and 95 Heated to 0 ° C. and held for 5 hours. Thereafter, the mixture was cooled, the aggregated particles were filtered, thoroughly washed with ion exchange water, and then dried to obtain a toner.
[0067]
The obtained toner had a volume average particle diameter of 7.8 μm and a variation coefficient of volume particle size distribution of 19.8%. The toner had no odor.
[0068]
Example 2
A toner was obtained in the same manner as in Example 1 except that 600 g of the aqueous resin dispersion B was used instead of the aqueous resin dispersion A. On the way, the average particle diameter of the aggregated particles formed before adding the anionic surfactant was 7.8 μm.
[0069]
The obtained toner had a volume average particle size of 8.1 μm and a variation coefficient of volume particle size distribution of 20.3%. The toner had no odor.
[0070]
Comparative Example 1
A toner was obtained in the same manner as in Example 1 except that 435 g of vinyl resin dispersion A was used instead of water resin dispersion A.
[0071]
The obtained toner had a volume average particle size of 5.5 μm and a variation coefficient of volume particle size distribution of 20.3%. The toner had no odor.
[0072]
Comparative Example 2
A toner was obtained in the same manner as in Example 1 except that 218 g of vinyl resin dispersion A and 217 g of vinyl resin dispersion B were used instead of water resin dispersion A.
[0073]
The obtained toner had a volume average particle size of 5.8 μm and a coefficient of variation in volume particle size distribution of 20.2%. Further, a mercaptan odor was detected in the toner.
[0074]
Comparative Example 3
A toner was obtained in the same manner as in Example 1 except that 218 g of the vinyl resin dispersion A and 294 g of the polyester resin dispersion A were used in place of the aqueous resin dispersion A. On the way, the average particle diameter of the aggregated particles formed before adding the anionic surfactant was 7.8 μm.
[0075]
The obtained toner had a volume average particle size of 8.0 μm and a volume particle size distribution variation coefficient of 32.4%. The toner had no odor.
[0076]
Test example
Using a heat roll fixing machine set at a linear speed of 200 mm / sec and a surface temperature of 170 ° C., the toner was fixed and a tape peeling test was performed. Furthermore, the surface temperature of the heat roll was raised to confirm the offset generation temperature. Table 1 shows the offset generation temperatures of Examples and Comparative Examples.
[0077]
[Table 1]

[0078]
As a result, the toners obtained in Examples 1 and 2 and Comparative Examples 2 and 3 did not peel and had sufficient fixability. On the other hand, the toner obtained in Comparative Example 1 was peeled off and the fixability was insufficient. In addition, the toners obtained in Comparative Examples 2 and 3 had good fixability as described above, but the toner obtained in Comparative Example 2 had a strange odor, and Comparative Example 3 had a wide particle size distribution. Only toner was obtained.
[0079]
Further, when attention is paid to the offset generation temperature, it can be seen that the toner of Example 2 containing an unsaturated polyester has a higher offset generation temperature than the toner of Example 1. This is presumably due to grafting of polyester and vinyl resin.
[0080]
【The invention's effect】
According to the present invention, it is possible to easily obtain a toner having a small particle diameter which does not have a strange odor and has good fixing properties.

Claims (5)

A method for producing a toner comprising a step of forming aggregated particles from an aqueous resin dispersion containing a neutralized product of a vinyl resin and a polyester having an acid value of 5 to 50 mgKOH / g, wherein the aqueous resin dispersion comprises: A method for producing a toner, which is a resin dispersion obtained by polymerizing a raw material monomer of the vinyl resin in the presence of a neutralized product of the polyester. A water-based resin dispersion is obtained by mixing a polyester and a base material, a vinyl-based resin raw material monomer and water to obtain a dispersion containing a neutralized polyester, and then polymerizing the vinyl-based resin raw material monomer. The production method according to claim 1, which is a resin dispersion. The manufacturing method of Claim 1 or 2 in which polyester contains unsaturated polyester. The production method according to claim 1, wherein the polymerization of the raw material monomer of the vinyl resin is performed in the presence of a hydrophobic polymerization initiator. The manufacturing method according to any one of claims 1 to 4, wherein a weight ratio of the vinyl resin to the neutralized polyester (a vinyl resin / neutralized polyester) is 50/50 to 95/5.