JP4018020B2 - Toner production method - Google Patents

Description

【０１２１】
上述した評価基準に基づき評価を行なった結果、表１に示したように、本発明の条件に合致する、即ち、樹脂帯電制御剤の単位重量当たりの酸性解離基のグラム当量数が、非水溶性樹脂の単位重量当たりの酸性解離基のグラム当量数より多い実施例１乃至６は合格であり、本発明の条件に合致しない、即ち、樹脂帯電制御剤の単位重量当たりの酸性解離基のグラム当量数が、非水溶性樹脂の単位重量当たりの酸性解離基のグラム当量数より少ない比較例１乃至８は不合格であることが判った。
【０１２２】
【発明の効果】
本発明によるトナーの製造方法を用いると、樹脂帯電制御剤の単位重量当たりの酸性解離基のグラム当量数が、非水溶性樹脂の単位重量当たりの酸性解離基のグラム当量数より多くすることにより、トナー樹脂中に樹脂帯電制御剤を効率良く均一に含有でき、トナーを製造する時の帯電制御剤利用効率が高く、内包する帯電制御剤の濃度調整ができる。それによって、このトナーを用いて画像を形成した場合、カブリや画像濃度ムラがなく、良好な画像が得られる。[0001]
[Technical field to which the invention belongs]
The present invention relates to a method for producing a toner for developing an electrostatic latent image used for image formation by electrophotography or the like. More specifically, the present invention relates to a method for producing a toner used for electrostatic latent image development, which contains at least a water-insoluble resin, a colorant, and a resin charge control agent.
[0002]
[Prior art]
As an electrostatic charge image developer, a two-component developer containing toner particles and carrier particles and a one-component developer containing magnetic toner particles or non-magnetic toner particles are known. The toner particles for the developer are roughly divided into a dry method and a wet method. The dry method includes a pulverization method in which a binder resin, a colorant, a charge control agent and the like are kneaded and pulverized and classified, and a wet method. , A polymerization method in which a colorant, a charge control agent, etc. are included during polymerization of the binder resin, and a resin dispersion is prepared by emulsion polymerization, while a colorant, a charge control agent, etc. are dispersed in a solvent. After preparing an agent dispersion and mixing these to form agglomerated particles, an emulsion polymerization agglomeration method that fuses by heating to obtain toner, a resin having an acid group described in Patent Document 1 below, etc. After the colorant was dispersed and mixed in a solution dissolved in an organic solvent, the acid group of the resin was neutralized with a base to prepare a colorant mixture, which was emulsified by adding water and encapsulated in an aqueous medium. Phase inversion emulsification to produce particles and dry to obtain toner Such as are known.
[0003]
When including a step of generating toner particles in an aqueous solution by a wet method, additives other than the binder resin, such as colorants and charge control agents, are incorporated into the binder resin after being formed into particles of toner particle size. Is required.
[0004]
[Patent Document 1]
Japanese Patent No. 3063269
[0005]
[Problems to be solved by the invention]
However, when the toner is produced by the above-described wet method, depending on the combination of the resin and the charge control agent, (1) it is difficult to produce a toner containing the charge control agent. (2) A desired amount of the charge control agent. However, it was difficult to be contained in the resin particles.
[0006]
For example, when it is allowed to act with water in the emulsification process, the charge control agent that is uniformly dispersed or dissolved in the organic phase is unevenly distributed or agglomerated, so that the charge control agent is not evenly taken into the toner and the toner If the content of the charge control agent is different, the image formability is lowered.
[0007]
Further, in order to efficiently and uniformly enclose the charge control agent in the binder synthetic resin, it is necessary to suppress discharge of the charge control agent to the aqueous layer in the emulsification step.
[0008]
The present invention has been made in view of such circumstances, and an object of the present invention is to provide a toner manufacturing method using an emulsification method in which a resin charge control agent is uniformly present inside and on the surface of the toner. .
[0009]
[Means for Solving the Problems]
As a result of diligent research, the present inventors have found that the above-mentioned problems can be solved by using a specific water-insoluble resin and a specific resin charge control agent in a toner production method using an emulsification method. Reached.
[0010]
That is, the present invention emulsifies, in an aqueous solution, a mixture containing at least one water-insoluble resin having an acidic dissociable group, a colorant, and a resin charge control agent in an aqueous solution. In the toner production method, after producing the water-insoluble resin particles containing the charge control agent, separating the water-insoluble resin particles and drying it, the unit charge per unit weight of the resin charge control agent In this toner production method, the number of gram equivalents of acid dissociable groups is greater than the number of gram equivalents of acid dissociable groups per unit weight of the water-insoluble resin.
[0011]
In order to include the charge control agent in the toner particles without impairing the effect across the steps of forming the toner particles in the aqueous solution, the charge control agent must not be soluble in water. Further, in toner particles containing at least a water-insoluble resin, a colorant, and a charge control agent, the charge control agent must be contained substantially uniformly among the toner particles. In addition, the charge control agent must be present on the toner particle surface.
[0012]
Therefore, in the present invention, as the resin charge control agent, the number of gram equivalents of acidic dissociable groups per unit weight contained therein is the number of gram equivalents of acidic dissociable groups per unit weight of the water-insoluble resin that is the binder resin. It is solved by selecting more than. Even when the process of forming toner particles in an aqueous solution is crossed, the resin charge control agent has a larger number of dissociating groups than the binder resin, that is, has a higher hydrophilicity, so that it is less likely that the resin charge control agent is buried in the toner and cannot exert its effect. For this reason, it turned out that it can adjust to desired charge amount by changing addition amount.
[0013]
In the present invention, at least one water-insoluble resin having an acid-dissociable group, a colorant, and the number of gram equivalents of acid-dissociable groups per unit weight are the acid-dissociable groups per unit weight of the water-insoluble resin. A mixture containing a resin charge control agent larger than the number of gram equivalents as an essential component can be obtained by heating and melting them, or by dissolving them using an organic solvent.
[0014]
That is, at least one water-insoluble resin having an acid dissociable group, a colorant, and the number of gram equivalents of acid dissociable groups per unit weight is the gram equivalent of acid dissociable groups per unit weight of the water-insoluble resin. A uniform toner having a characteristic that can be adjusted to a desired charge amount by emulsifying a mixture containing a resin charge control agent larger than a number of essential components into an aqueous solution through a process obtained by heating and melting, and a method for producing the same Can be provided.
[0015]
Further, the number of gram equivalents of the acid dissociable group per unit weight of the water-insoluble resin is at least one water-insoluble resin having an acid dissociable group, the colorant, and the number of gram equivalents of the acid dissociable group per unit weight. Easily without mixing by melt-kneading by using a process obtained by dissolving a mixture containing more than a number of resin charge control agents using an organic solvent that dissolves the resin and the resin charge control agent. It is possible to provide a toner having uniform characteristics that can be mixed with each other and adjusted to a desired charge amount, and a method for producing the same.
[0016]
In the present invention, it is preferable to use a resin containing at least a polyester-based resin as the water-insoluble resin. As a result, a toner having a good balance of powder fluidity and fixing property can be easily obtained, and a toner that can also be applied to a color toner can be obtained.
[0017]
In the present invention, it is preferable to use a water-insoluble resin containing a carboxyl group. As a result, the toner is easily neutralized, the hydrophilicity of the resin is increased, and a toner manufacturing method in which a mixture of the resin, the resin charge control agent, the colorant, and the like is easily emulsified.
[0018]
In the present invention, it is preferable to use a resin charge control agent containing at least a sulfonic acid group-containing monomer as a constituent unit as a monomer. As a result, a toner having negatively chargeable toner can be obtained.
[0019]
In the present invention, the resin charge control agent is preferably contained in an amount of 0.1 to 20% by weight based on the toner particles. As a result, a toner having a uniform characteristic that can be adjusted to a desired charge amount and a method for manufacturing the same are obtained.
[0020]
Further, according to the present invention, a toner capable of satisfactorily forming a black or color image can be obtained by using a colorant containing one or more coloring materials of black, cyan, yellow and magenta.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below.
According to the present invention, as the resin charge control agent, the number of gram equivalents of acidic dissociation groups per unit weight of the resin charge control agent is larger than the number of gram equivalents of acid dissociation groups per unit weight of the water-insoluble resin. A toner production method characterized in that a binder resin is emulsified or dispersed in an aqueous solution to form particles in the aqueous solution.
[0022]
[Water-insoluble resin]
The water-insoluble resin, which is a binder resin used in the present invention, includes a resin that can become a self-water dispersible resin by neutralization. A self-water dispersible resin is a resin having an acidic or basic hydrophilic dissociation group in the molecular chain. If the dissociation group is acidic, the neutralizing agent is a base, and if the dissociation group is basic, the neutralizing agent is an acid. By neutralizing with the use of, the dissociation group forms a salt, the hydrophilicity is improved, and self-water dispersibility is obtained.
[0023]
The degree of hydrophilicity improved by neutralization must be such that the resin itself can be dispersed in water. The self-water dispersible resin thus obtained is mixed with an aqueous solution to cause emulsification, and particles can be generated in the aqueous solution. For example, a self-water dispersible polyester resin takes a form in which a hydrophilic dissociation group is formed on the surface of a resin particle in an aqueous solution so as to enclose a hydrophobic portion so that the particle becomes stable. The hydrophilic dissociating group has the same effect whether it is formed by neutralizing the dissociating group in the resin with a neutralizing agent, or when the salt structure neutralized from the beginning is retained as the resin.
[0024]
Examples of the neutralizing agent include resins such as ammonia, sodium hydroxide, potassium hydroxide, and triethylamine in the case of a resin mainly containing an acidic group, and in the case of a resin mainly including a basic group, for example, Examples include hydrochloric acid and acetic acid. These neutralizing agents neutralize an appropriate amount of hydrophilic dissociation groups in the resin.
[0025]
The hydrophilicity of the water-insoluble resin can be adjusted by the amount of hydrophilic dissociation groups in the resin and the neutralization rate thereof, and the size of the particles when dispersed is determined accordingly.
[0026]
The amount of the hydrophilic dissociation group (acidic group or basic group) that the water-insoluble resin has in the resin is not particularly limited, but is 10 mg equivalent to 1000 mg equivalent per 100 g of resin solid content.
[0027]
Furthermore, the amount of neutralized acidic groups or basic dissociation groups necessary for the water-insoluble resin to exhibit self-water dispersibility depends on the molecular structure, molecular weight, etc. of the resin itself. Although they are different, they are usually 1 mg equivalent to 500 mg equivalent to 100 g of resin solid content.
[0028]
It is preferable to use a water-insoluble resin having a glass transition temperature of 30 to 100 ° C. and a weight average molecular weight of the resin of 5,000 to 500,000.
[0029]
Specific examples of the water-insoluble resin that is a binder resin include, for example, polyester resins, polyurethane resins, epoxy resins, styrene-acrylic resins, and the like. A polyester resin that can easily obtain a balance of powder fluidity and fixability as a toner is relatively preferable. Moreover, you may use the resin which grafted both using the advantage of both a polyester resin and a styrene-acryl copolymer. By using a polyester resin, it is possible to fix at low temperature by making use of sharp melt properties, and it is also suitable for color toners because of its excellent transparency and secondary color reproducibility.
[0030]
Next, taking polyester resin as an example, it will be described in detail.
The polyester water-insoluble resin in the present invention includes, for example, a polyester resin that can become self-water dispersible by neutralization. This is due to the action of a dissociating group present in the resin molecule, which can increase hydrophilicity by neutralization, and can form stable particles in an aqueous solution without substantially using an emulsifier or a dispersion stabilizer. It is a polyester resin.
[0031]
Self-water-dispersible polyester resins, that is, polyester resins that can become self-water-dispersible resins by neutralization can be synthesized and used by known synthesis methods. For example, a polyester resin that can be a self-water dispersible resin having a carboxyl group as a hydrophilic group is synthesized by a normal polycondensation reaction.
[0032]
That is, the raw polybasic acid and polyhydric alcohol are subjected to dehydration condensation in the presence of a catalyst in the presence or absence of a solvent. A part of the polybasic acid may be subjected to demethanol polycondensation using the methyl esterified product.
[0033]
Examples of the polybasic acid used include terephthalic acid, isophthalic acid, phthalic anhydride, trimellitic anhydride, pyromellitic acid, naphthalenedicarboxylic acid and other aromatic carboxylic acids, maleic anhydride, fumaric acid, succinic acid, alkenyl anhydride And aliphatic carboxylic acids such as succinic acid and adipic acid.
[0034]
Examples of the polyhydric alcohol used include aliphatic polyhydric alcohols such as ethylene glycol, propylene glycol, butanediol, hexanediol, neopentyl glycol, and glycerin, cyclohexanediol, cyclohexanedimethanol, hydrogenated bisphenol A, and the like. Examples include aromatic diols such as alicyclic polyhydric alcohols, ethylene oxide adducts of bisphenol A, and propylene oxide adducts of bisphenol A.
[0035]
For example, the content of the terminal carboxyl group can be controlled by the blending ratio and reaction rate of the polybasic acid and the polyhydric alcohol which are the raw materials of the polyester. Alternatively, carboxyl groups can be easily introduced into the main chain by using trimellitic anhydride.
[0036]
The polycondensation reaction is terminated when the acid value and the softening point reach predetermined values, and a desired polyester resin that can be self-water-dispersible can be obtained.
[0037]
The polyester resin system has been described above. However, in other resin systems, a urethane resin, an epoxy resin, an acrylic resin, or the like can be used instead of the polyester resin.
[0038]
When the resin is a urethane-based resin, for example, a diol containing an acidic group or a basic group such as dimethylolpropionic acid or N-methyldiethanolamine, a polyether polyol such as polyethylene glycol, a polyester polyol, an acrylic polyol, or a polybutadiene. As part of various polyol components such as polyols, acidic groups or basic group-containing urethane resins can be obtained by known methods such as addition polymerization with polyisocyanates such as tolylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, etc. .
[0039]
When the resin is an epoxy resin, for example, by addition or addition polymerization of a polyvalent carboxylic acid such as adipic acid or trimellitic anhydride to the base epoxy resin, or by addition or addition polymerization of dibutylamine, ethylenediamine, or the like, An epoxy resin containing an acidic group or a basic group is obtained.
[0040]
When the resin is an acrylic resin, for example, a polymerizable monomer other than an acrylic polymerizable monomer containing an acidic group or a basic group and a polymerizable monomer containing a hydrophilic group Can be obtained by radical polymerization in the presence of a radical initiator. The polymerization reaction for obtaining it can be used as appropriate in solution polymerization, suspension and emulsion polymerization.
[0041]
The water-insoluble resin to be used may be a single resin or a mixture of a plurality of resins having different molecular weights and monomer compositions.
[0042]
The dissociation group of the water-insoluble resin of the present invention includes an acid dissociation group or a basic dissociation group, but an acid dissociation group is used for the purpose of providing a negatively chargeable toner. The density | concentration of the dissociation group compared per unit weight as described in this invention means the comparison of acidic dissociation groups, or the comparison of basic dissociation groups. An acidic dissociation group is desirable in order to make the toner charge negative. Examples of the acidic dissociable group include a carboxyl group, a sulfonic acid group, and a phosphoric acid group. Among these, a carboxyl group is preferable as an acidic group. The reason for this is that it is a weakly acidic group, so that it is easy to neutralize dissociated groups by the base, which is necessary during the emulsification process. Etc.
[0043]
[Colorant]
A known colorant can be used for the toner particles of the present invention, but there is no limitation as long as it is a dye or pigment that has been used as a toner material so far. For example, as shown below Organic or inorganic dyes and pigments can be used.
[0044]
That is, examples of the black colorant include carbon black, copper oxide, manganese dioxide, aniline / black, activated carbon, nonmagnetic ferrite, magnetic ferrite, and magnetite.
[0045]
Yellow colorants include chrome yellow, zinc yellow, cadmium yellow, yellow iron oxide, mineral fast yellow, nickel titanium yellow, navel yellow, naphthol yellow S, Hansa Yellow G, Hansa Yellow 10G, Benzidine Yellow G, Benzidine Yellow GR Quinoline yellow lake, permanent yellow NCG, tartrazine lake, C.I. I. Pigment yellow 12, C.I. I. Pigment yellow 13, C.I. I. Pigment yellow 14, C.I. I. Pigment yellow 15, C.I. I. Pigment yellow 17, C.I. I. Pigment yellow 93, C.I. I. Pigment yellow 94, C.I. I. And compounds such as CI Pigment Yellow 138.
[0046]
Examples of the orange colorant include red yellow lead, molybdenum orange, permanent orange GTR, pyrazolone orange, Vulcan orange, Indanthrene Brilliant Orange RK, Benzidine Orange G, Indanthrene Brilliant Orange GK, C.I. I. Pigment orange 31, C.I. I. And compounds such as CI Pigment Orange 43.
[0047]
Red colorants include bengara, cadmium red, red lead, mercury sulfide, cadmium, permanent red 4R, risor red, pyrazolone red, watching red, calcium salt, lake red C, lake red D, brilliant carmine 6B, eosin Lake, Rhodamine Lake B, Alizarin Lake, Brilliant Carmine 3B, C.I. I. Pigment red 2, C.I. I. Pigment red 3, C.I. I. Pigment red 5, C.I. I. Pigment red 6, C.I. I. Pigment red 7, C.I. I. Pigment red 15, C.I. I. Pigment red 16, C.I. I. Pigment red 48: 1, C.I. I. Pigment red 53: 1, C.I. I. Pigment red 57: 1, C.I. I. Pigment red 122, C.I. I. Pigment red 123, C.I. I. Pigment red 139, C.I. I. Pigment red 144, C.I. I. Pigment red 149, C.I. I. Pigment red 166, C.I. I. Pigment red 177, C.I. I. Pigment red 178, C.I. I. And compounds such as CI Pigment Red 222.
[0048]
Examples of purple colorants include compounds such as manganese purple, fast violet B, and methyl violet lake.
[0049]
Blue colorants include bitumen, cobalt blue, alkali blue lake, Victoria blue lake, phthalocyanine blue, metal free phthalocyanine blue, phthalocyanine blue partially chlorinated, first sky blue, induslen blue BC, C.I. I. Pigment blue 15, C.I. I. Pigment blue 15: 2, C.I. I. Pigment blue 15: 3, C.I. I. Pigment blue 16, C.I. I. And compounds such as CI Pigment Blue 60.
[0050]
Examples of green colorants include chromium green, chromium oxide, pigment green B, micalite green lake, final yellow green G, C.I. I. And compounds such as CI Pigment Green 7.
[0051]
Examples of the white colorant include compounds such as zinc white, titanium oxide, antimony white, and zinc sulfide.
[0052]
[Resin charge control agent]
A known resin charge control agent can be used for the toner particles of the present invention. However, the number of gram equivalents of acidic dissociable groups per unit weight of the resin charge control agent is selected to be larger than the number of gram equivalents of acidic dissociable groups per unit weight of the binder resin used.
[0053]
In order to include the charge control agent in the toner particles without impairing the effect across the steps of forming the toner particles in the aqueous solution, the charge control agent must not be soluble in water. In toner particles containing at least a water-insoluble resin, a colorant, and a resin charge control agent, the charge control agent must be contained substantially uniformly among the toner particles. The charge control agent must also be present on the toner particle surface.
[0054]
In order to solve these problems, as the resin charge control agent, the number of gram equivalents of acidic dissociation groups per unit weight contained therein is acidic dissociation groups per unit weight of a water-insoluble resin resin that is a binder resin. This is solved by selecting more than the number of gram equivalents. Even when the toner particle formation process in an aqueous solution is straddled, the resin charge control agent has a larger number of dissociated groups than the binder resin, that is, has a higher hydrophilicity. It was found that the desired charge amount can be adjusted by changing the addition amount.
[0055]
As a method for quantitatively characterizing the acid-base dissociation group concentration of the resin charge control agent, potentiometric titration is used. This makes it possible to grasp the amount of dissociative groups that show acidity or basicity of the resin charge control agent, and by controlling the acidity and basicity, it is possible to produce toner with the same charge amount for each production. It becomes possible.
[0056]
As the acidic resin charge control agent that can be used in the present invention, those having an acid amount larger than the base amount are used. On the other hand, among the resin charge control agents, those having a base amount greater than an acid amount are used as the basic resin charge control agent. The amount of acidic dissociation groups or basic dissociation groups of the resin charge control agent is made larger than that of the resin.
[0057]
The resin charge control agent is not necessarily a single component, and in some cases, a plurality of components may be used. In this case, the acidity per unit weight or the number of gram equivalents of the basic dissociation group is acidic per unit weight of the resin. Or if it is made higher than the gram equivalent number of a basic dissociation group, there will be no problem.
[0058]
The particle size of the resin charge control agent can be selected as appropriate, but the smallest possible one is used in order to increase the compatibility with the water-insoluble resin as the binder resin and the dispersibility in the binder resin.
[0059]
In the present invention, a known resin charge control agent can be used, and the side chain of the polymer is selected from a sulfonic acid group, a carboxylic acid group, a phenol group, a thiophenol group, or a salt thereof. A resin having a substituent may be mentioned. In the present invention, it is desirable to use at least a sulfonic acid group-containing monomer as one of the monomers constituting the resin charge control agent. Resin containing a carboxyl group or a carboxyl group base-containing monomer or a sulfonic acid or a sulfonate group-containing monomer as a constituent component improves the charge imparting effect. This is preferable because it has an effect of increasing the negative chargeability.
[0060]
Examples of the salt formed by the substituent attached to the side chain of the polymer include salts formed with alkali metal, alkaline earth metal ions, and salts formed with organic bases such as amines and quaternary ammonium.
[0061]
In addition, when the resin charge control agent in the present invention is less than 0.1% by weight, no effect is obtained, and when it exceeds 20% by weight, the dispersion in the toner resin is deteriorated, so that the charge distribution becomes wide and fogging occurs. The difference in charge amount between high temperature and high humidity and low temperature and low humidity is large.
[0062]
The resin charge control agent used in the present invention is obtained by copolymerizing an aromatic or aliphatic polymerizable monomer containing a sulfonic acid group or a salt thereof and another polymerizable monomer copolymerizable therewith.
[0063]
Specific examples of the monomer having a sulfonyl group as an acid group include 2-acrylamido-2-methylpropanesulfonic acid, 2-methacrylamide-2-methylpropanesulfonic acid, styrenesulfonic acid, and 2-acryloyl-2-methylpropanesulfone. Examples thereof include acid and 2-methacryloyl-2-methylpropanesulfonic acid.
[0064]
Examples of the aromatic sulfonic acid group-containing monomer include alkali metal salts such as vinyl sulfonic acid, allyl vinyl sulfonic acid, 2-acrylamido-2-methylpropane sulfonic acid, methacryloyloxyethyl sulfonic acid, alkaline earth metal salts, amine salts, and the like. A quaternary ammonium salt etc. are mentioned.
[0065]
Examples of the aliphatic sulfonic acid group-containing monomer include alkali metal salts such as styrene sulfonic acid, sulfophenyl acrylamide, sulfophenyl maleimide, and sulfophenyl itaconimide, alkaline earth metal salts, amine salts, and quaternary ammonium salts. .
[0066]
Examples of other polymerizable monomers that can be copolymerized include aromatic vinyl monomers and ethylenically unsaturated carboxylic acid ester monomers. Examples thereof include styrene derivatives such as styrene, α-methylstyrene, β-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, 2,4-dimethylstyrene, pn-butylstyrene, p-tert-butylstyrene, pn-hexylstyrene, pn-octylstyrene, pn-nonylstyrene, pn-decylstyrene, pn-dodecylstyrene, p-methoxystyrene, p-phenyl Acrylic polymerizable monomers such as styrene such as methyl acrylate, ethyl acrylate, n-propyl acrylate, iso-propyl acrylate, n-butyl acrylate, iso-butyl acrylate, tert-butyl acrylate, n-amyl acrylate, n-hexyl acrylate, 2-Eth Methacrylic polymerizable monomers such as hexyl acrylate, n-octyl acrylate, n-nonyl acrylate, cyclohexyl acrylate, benzyl acrylate, dimethyl phosphate ethyl acrylate, diethyl phosphate ethyl acrylate, dibutyl phosphate ethyl acrylate, 2-benzoyloxyethyl acrylate As methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, iso-propyl methacrylate, n-butyl methacrylate, iso-butyl methacrylate, tert-butyl methacrylate, n-amyl methacrylate, n-hexyl methacrylate, 2-ethylhexyl methacrylate, n-octyl Methacrylate, n-nonyl methacrylate, diechi Phosphate ethyl methacrylate, dibutyl phosphate ethyl methacrylate, etc., methylene aliphatic monocarboxylic acid ester, etc., vinyl ester as vinyl acetate, vinyl propionate, vinyl butyrate, vinyl benzoate, vinyl formate, etc., vinyl ether as vinyl methyl ether, vinyl ethyl Examples of the vinyl ketone include ether and vinyl isobutyl ether, and vinyl methyl ketone, vinyl hexyl ketone, and vinyl isopropyl ketone. Other polymerizable monomers having a plurality of functional groups, specifically diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol diacrylate, 1,6-hexanediol diacrylate, neopentyl glycol acrylate, Tripropylene glycol diacrylate, polypropylene glycol diacrylate, 2,2′-bis (4- (acryloxydiethoxy) phenyl) propane, trimethylolpropane triacrylate, tetramethylolmethane tetraacrylate, ethylene glycol dimethacrylate, diethylene glycol di Methacrylate, triethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, Polyethylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate, 1,6-hexanediol dimethacrylate, neopentyl glycol dimethacrylate, polypropylene glycol dimethacrylate, 2,2′-bis (4- (methacryloxy / polyethoxy) phenyl) Propane, trimethylolpropane trimethacrylate, tetramethylolmethane tetramethacrylate, divinylbenzene, divinyl ether and the like can be used.
[0067]
There is no restriction | limiting in particular as a polymerization initiator which can be used in making it copolymerize, The well-known azo initiator or peroxide initiator etc. which are normally used in a radical polymerization reaction can be used.
[0068]
[Measurement of number of dissociated groups]
In the present invention, the number of dissociable groups (acid value, hydroxyl value) per unit weight of the water-insoluble resin and the resin charge control agent is determined, for example, by the following method. The basic operation conforms to Japanese Industrial Standard J1S K 0070, but the reagents used, their types, instruments, etc. are not limited to these.
[0069]
(Measurement of the number of acidic dissociable groups (acid value))
・ Devices and instruments
Flask, burette, water bath or heater
·reagent
0.1 kmol / m ^Three hydrochloric acid
0.1 kmol / m ^Three Potassium hydroxide ethanol solution (standard is 0.1 kmol / m ^Three Take 25 ml of hydrochloric acid in an Erlenmeyer flask using a whole pipette, add phenolphthalein solution, 0.1 kmol / m ^Three Titrate with potassium hydroxide ethanol solution, and determine the factor from the amount required for neutralization. )
Phenolphthalein solution
Solvent (diethyl ether and ethanol mixed at a volume ratio of 1: 1 or 2: 1. Just before use, a few drops of phenolphthalein solution was added as an indicator, and 0.1 kmol / m ^Three Neutralize with potassium hydroxide ethanol solution. )
・ Measurement method
(A) Weigh resin precisely in flask.
(B) Add a few drops of phenolphthalein solution as solvent and indicator and shake well until the resin is completely dissolved in a water bath.
(C) Titrate with a 0.1 kmol / m3 potassium hydroxide ethanol solution, and the end point is when the red color of the indicator no longer disappears.
・ Calculation
A = 5.611 × B × f / S
However, A: Acid value (mgKOH / g)
B: 0.1 kmol / m used for titration ^Three Amount of potassium hydroxide ethanol solution (ml)
f: 0.1 kmol / m ^Three Factor of potassium hydroxide ethanol solution
S: Mass of resin (g)
5.611: Formula weight of potassium hydroxide 56.11 × 1/10
[0070]
(Measurement of the number of basic dissociation groups (hydroxyl value))
・ Devices and instruments
Measuring cylinder, pipette, flask, oil bath
·reagent
Acetylation reagent (for example, acetic anhydride in a flask, pyridine added, and shaken well)
Phenolphthalein solution
0.5 kmol / m ^Three Potassium hydroxide ethanol solution
・ Measurement method
(A) A resin is precisely weighed in a predetermined amount of flask, and an acetylating reagent is added thereto using a pipette.
(B) The flask is heated by immersing it in an oil bath having a temperature of 95-100 ° C.
(C) After 1 hour, the flask is removed from the oil bath, allowed to cool, water is added and shaken to decompose acetic anhydride.
(D) Further, in order to complete the decomposition, the flask is again heated in an oil bath for 10 minutes, allowed to cool, and then the flask wall is washed with ethanol.
(E) Add a few drops of phenolphthalein solution as indicator, 0.5 kmol / m ^Three Titrate with potassium hydroxide ethanol solution, and the end point is when the light red color of the indicator no longer disappears.
(F) In the blank test, (a) to (e) are performed without adding resin.
(G) If the sample is difficult to dissolve, add a small amount of pyridine, or add another solvent such as xylene, toluene, or THF to dissolve it.
・ Calculation
A = [{(BC) × 28.05 × f} / S] + D
Where A: hydroxyl value (mgKOH / g)
B: 0.5 kmol / m used for blank test ^Three Amount of potassium hydroxide ethanol solution (ml)
C: 0.5 kmol / m used for titration ^Three Amount of potassium hydroxide ethanol solution (ml)
f: 0.5 kmol / m ^Three Factor of potassium hydroxide ethanol solution
S: Mass of resin (g)
D: Acid value
28.05: Formula weight of potassium hydroxide 56.11 × 1/2
[0071]
Therefore, the concentration of the dissociating group per unit weight of the water-insoluble resin and the resin charge control agent described in the present invention can be determined from the acid value and hydroxyl value obtained by potentiometric titration. For example, the amount of acidic dissociation groups contained per resin amount (g) is KOH (mg) / (1000 × KOH formula amount) used for neutralization.
[0072]
The solvent for determining the dissociation group of the water-insoluble resin and the resin charge control agent is changed to a solvent that is soluble depending on the type of resin, and the base and acid of the neutralizing agent are not particularly limited, and appropriate ones from commercially available products should be used. A commercially available measuring device can also be used.
[0073]
[Emulsifier etc.]
The emulsifier used for emulsification in the present invention is not particularly limited, and any emulsifier and disperser that are generally commercially available can be used. For example, batch type such as Ultra Turrax (manufactured by IKA), Polytron homogenizer (manufactured by Kinematica), TK auto homomixer (manufactured by Special Machine Industries Co., Ltd.), National Cooking Mixer (manufactured by Matsushita Electric Industrial Co., Ltd.) Emulsifier, Ebara Milder (manufactured by Ebara Manufacturing Co., Ltd.), TK Pipeline Homomixer, TK Homomic Line Flow, Philmix (manufactured by Tokushu Kika Kogyo Co., Ltd.), colloid mill (manufactured by Shinko Pantech Co., Ltd.), Continuous emulsifiers such as Thrasher, Trigonal Wet and Fine Crusher (Mitsui Miike Chemical Co., Ltd.), Cavitron (Eurotech Co., Ltd.), Fine Flow Mill (Pacific Kiko Co., Ltd.), Claremix (M Technique Co., Ltd.) , Etc.), batches such as Fillmix (made by Tokushu Kika Kogyo Co., Ltd.), continuous emulsifiers etc. It is not limited to these.
[0074]
Examples of other components (additive components) that can be used in the present invention include various auxiliary agents such as low-molecular charge control agents and release agents. Accordingly, it can be selected and used as appropriate.
[0075]
[Production method]
Next, a specific production method of the present invention will be described below by taking as an example a resin that can become self-water dispersible by neutralization as a water-insoluble resin.
[0076]
First, a self-water dispersible resin obtained by neutralizing a resin that can become self-water dispersible by neutralization in the first step with a neutralizer, an organic solvent that dissolves the resin, a colorant, and resin charge control A mixture in which the agent and other additives as required are uniformly mixed is prepared.
[0077]
In the case of a water-insoluble resin that has an acid dissociable group and this acid dissociable group is neutralized with a base to form a self-water dispersible resin, the number of gram equivalents of the acid dissociable group per unit weight is the unit of the resin. More than the number of gram equivalents of acidic dissociable groups per weight is mixed with the resin charge control agent. In the case of a water-insoluble resin that has a basic dissociating group and is neutralized with an acid group to form a self-water dispersible resin, the number of gram equivalents of the basic dissociating group per unit weight is The resin charge control agent is mixed with more than the gram equivalent number of basic dissociation groups per unit weight of the resin.
[0078]
The resin charge control agent and the colorant are mixed by a known dispersing means such as a disperser.
When obtaining a mixture using an organic solvent, a resin and an organic solvent are mixed, and a resin charge control agent, a colorant, and the like are dispersed by a disperser or the like.
[0079]
As the solvent that can be used in the dissolving step of the present invention, any known and commonly used solvents can be used. As the solvent, one kind may be used alone, or two or more kinds may be used.
[0080]
In addition, this is not the case when the emulsion is neutralized and emulsified in an aqueous solution using a solid melt mainly composed of a water-insoluble resin and a neutralizing agent without using an organic solvent.
[0081]
In addition, the organic solvent is more hydrophilic than the organic solvent that dissolves the resin and the solvent from the viewpoint of ease of emulsification at the time of emulsification, the form (state) of the resulting particles, and the good particle size distribution. Mixtures with high, surface tension reducing organic solvents can also be used.
[0082]
Any organic solvent can be used as long as it dissolves the water-insoluble resin, but it is preferable to use a so-called low-boiling solvent such as methyl ethyl ketone or ethyl acetate which can be easily removed from the solvent. In addition, a water-soluble or highly hydrophilic organic solvent having a reduced surface tension such as acetone, butanol, isopropyl alcohol, hexanediol, tetrahydrofuran, dimethylformamide, butyl cellosolve, or the like can be used. In addition, a mixture of two or more solvents can be used as the solvent.
[0083]
When a mixture is obtained by melt-kneading without using an organic solvent, a resin charge control agent, a colorant and the like are further dispersed in the water-insoluble resin using a kneader. Thereafter, the obtained mixture may be used after being dissolved using an organic solvent that dissolves the resin, or may be emulsified as it is in an aqueous solution without using the organic solvent.
[0084]
The resin is neutralized in the required amount with a neutralizing agent before adding water in the next step. In the case of a resin having an acidic dissociation group or a basic dissociation group already neutralized and having self-water dispersibility, it is not necessary to neutralize in this step.
[0085]
In the second step, the mixture obtained in the previous step is emulsified to produce self-water dispersible resin particles containing a resin charge control agent, a colorant and the like.
[0086]
By adding water and emulsifying a mixture in which a self-dispersing resin in which a part or all of the dissociating groups have been neutralized is dissolved in an organic solvent, the resin is stably dispersed in the form of particles in water. The liquid temperature for emulsification is preferably about 10 to 40 ° C. However, since the particle size varies depending on the liquid temperature, it is necessary to maintain a constant temperature. As water to be used, ion-exchanged water or distilled water is preferable.
[0087]
If necessary for emulsification, a neutralizing agent may be added to water.
Further, if necessary, an emulsifier and a dispersion stabilizer may be used in combination.
[0088]
Examples of the emulsifier include anionic surfactants such as sodium lauryl sulfate, sodium dodecyl diphenyl oxide disulfonate and sodium dodecyl benzene sulfonate, and nonionic surfactants such as polyoxyethylene lauryl ether and polyoxyethylene nonylphenol ether. It is done.
[0089]
As the dispersion stabilizer, a water-soluble polymer compound is used, and examples thereof include polyvinyl alcohol, polyvinyl pyrrolidone, hydroxyethyl cellulose, carboxymethyl cellulose, and cellulose gum.
[0090]
The same manufacturing process can also be applied to a manufacturing method in which a water-insoluble resin is not dissolved in an organic solvent and is mixed with a resin charge control agent, a colorant and the like by melt kneading.
[0091]
In the third step, after emulsification, the particles are recovered from the water in which the generated particles are dispersed. In this step, a solvent removal treatment for removing the organic solvent from the toner and water is performed.
[0092]
Next, it processes using the neutralizing agent of the opposite polarity to the above-mentioned neutralizing agent which neutralized resin. That is, when the water-insoluble resin constituting the toner is neutralized with an acidic dissociation group, an acid is used. When the basic dissociation group is neutralized, a base is used to remove the resin from the original dissociation. Return to the original state. When this treatment is not performed, the toner is easily affected by moisture in the air, resulting in a defect in the chargeability of the toner.
[0093]
All of the above-described processes are not necessarily performed, and can be selected according to circumstances.
[0094]
Finally, particles are collected from the water by filtration, etc., and if necessary, washed to remove water-soluble components such as ions, impurities such as submicron fine particles, which affect the chargeability of the toner, and dried to a powder. A toner is obtained. The drying method may be any known drying method, and examples thereof include a freeze drying method and an airflow drying method.
[0095]
The obtained toner can be added with additives such as silica and titanium oxide, and various surface modifications can be performed. In addition, a charge control agent other than wax or resin can be added during the manufacturing process described above.
[0096]
【Example】
EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples.
[0097]
The toner evaluation in Examples or Comparative Examples was performed as follows.
The particle size and particle size distribution of the obtained toner were measured using a Coulter Multisizer (manufactured by Coulter).
[0098]
The average circularity of the obtained toner was measured using a flow type particle image analyzer FPIA-2000 (manufactured by Toa Medical Electronics Co., Ltd.). The average circularity is defined by (peripheral length of a circle having the same projection area as the particle image) / (peripheral length of the particle projection image) in the particle image detected by the measuring apparatus, and takes a value of 1 or less.
[0099]
Potentiometric titration of the number of grams equivalent of the amount of acidic dissociation groups of the water-insoluble resin and resin charge control agent is performed as follows. 1 g of the resin was dissolved in tetrahydrofuran and titrated with a commercially available N / 10 potassium hydroxide-ethanol solution (manufactured by Kishida Chemical). The number of gram equivalents of acidic dissociation groups possessed by the resin is determined from the amount of N / 10 potassium hydroxide-ethanol solution required for neutralization.
[0100]
Example 1
170 parts by weight of a polyester resin (acid value: 14 mg KOH / g) having an acid dissociation group of 0.250 mmol / g, 5 parts by weight of a resin charge control agent (acid value: 21 mg KOH / g) having an acid dissociation group of 0.374 mmol / g, methyl ethyl ketone After adding 180 parts by weight and dissolving well, 20 parts by weight of carbon black and 10 parts by weight of wax are added, and they are put into a Fillmix 56 type (made by Tokushu Kika Kogyo Co., Ltd.) and dispersed at 40 m / s for 5 minutes. After completion of the dispersion, the solid content was adjusted to 50% with methyl ethyl ketone to obtain a resin solution mixture. To 200 parts by weight of this resin solution mixture, 2 parts by weight of 1N ammonia water was added, the rotational speed of the homogenizer was set to 5000 RPM, and 100 parts of deionized water was added dropwise to emulsify and produce particles. Next, methyl ethyl ketone is removed by distillation under reduced pressure, ammonia on the particle surface is neutralized and removed using dilute hydrochloric acid, washed with filtered water, dried, mixed with hydrophobic silica, and mixed with a volume average particle size of 7 Toner particles having a diameter of 0.2 μm and a circularity of 0.97 were obtained. When the resin charge control agent was produced, a monomer mixture composed of styrene, 2-acrylamido-2-methylpropanesulfonic acid and acrylic acid was used.
[0101]
(Example 2)
170 parts by weight of a polyester resin (acid value: 14 mg KOH / g) having an acid dissociation group of 0.250 mmol / g, 5 parts by weight of a resin charge control agent (acid value: 40 mg KOH / g) having an acid dissociation group of 0.713 mmol / g, methyl ethyl ketone After adding 180 parts by weight and dissolving well, 20 parts by weight of carbon black and 10 parts by weight of wax are added, and they are put into a Fillmix 56 type (made by Tokushu Kika Kogyo Co., Ltd.) and dispersed at 40 m / s for 5 minutes. After completion of the dispersion, the solid content was adjusted to 50% with methyl ethyl ketone to obtain a resin solution mixture. To 200 parts by weight of this resin solution mixture, 2 parts by weight of 1N ammonia water was added, the rotational speed of the homogenizer was set to 5000 RPM, and 100 parts of deionized water was added dropwise to emulsify and produce particles. Subsequently, methyl ethyl ketone is removed by distillation under reduced pressure, ammonia on the particle surface is neutralized and removed using dilute hydrochloric acid, washed with filtered water, dried, mixed with hydrophobic silica, and mixed with a volume average particle size of 6 Toner particles having a diameter of 0.2 μm and a circularity of 0.97 were obtained. When the resin charge control agent was produced, a monomer mixture composed of styrene, 2-acrylamido-2-methylpropanesulfonic acid and acrylic acid was used.
[0102]
(Example 3)
170 parts by weight of a polyester resin (acid value: 14 mg KOH / g) having an acid dissociation group of 0.250 mmol / g, 5 parts by weight of a resin charge control agent (acid value: 28 mg KOH / g) having an acid dissociation group of 0.499 mmol / g, methyl ethyl ketone After adding 180 parts by weight and dissolving well, 20 parts by weight of carbon black and 10 parts by weight of wax are added, and they are put into a Fillmix 56 type (made by Tokushu Kika Kogyo Co., Ltd.) and dispersed at 40 m / s for 5 minutes. After completion of the dispersion, the solid content was adjusted to 50% with methyl ethyl ketone to obtain a resin solution mixture. To 200 parts by weight of this resin solution mixture, 2 parts by weight of 1N ammonia water was added, the rotational speed of the homogenizer was set to 5000 RPM, and 100 parts of deionized water was added dropwise to emulsify and produce particles. Subsequently, methyl ethyl ketone is removed by distillation under reduced pressure, ammonia on the particle surface is neutralized and removed using dilute hydrochloric acid, washed with filtered water, dried, mixed with hydrophobic silica, and mixed with a volume average particle size of 6 Toner particles having a diameter of 0.8 μm and a circularity of 0.97 were obtained. When producing the resin charge control agent, a monomer mixture comprising styrene, 2-ethylhexyl acrylate, and 2-acrylamido-2-methylpropanesulfonic acid was used.
[0103]
(Example 4)
Toner particles having a volume average particle diameter of 6.5 μm and a circularity of 0.97 were obtained in the same manner as in Example 1 except that 20 parts by weight of copper phthalocyanine was used instead of carbon black.
[0104]
(Example 5)
Toner particles having a volume average particle diameter of 7.5 μm and a circularity of 0.97 were obtained in the same manner as in Example 1 except that 20 parts by weight of Pigment Yellow 17 was used instead of carbon black.
[0105]
(Example 6)
Mitsui Mining Co., Ltd. made a raw material that was mixed with 170 parts by weight of a polyester resin (acid value: 12 mg · KOH / g), 20 parts by weight of carbon black and 10 parts by weight of wax into a Henschel mixer, and mixed for 10 minutes. The resin mixture was obtained by melt-kneading and dispersing at 120 ° C. or less with a Niedix MOS 140-800. To 100 parts by weight of this resin mixture, 100 parts by weight of methyl ethyl ketone was added and dissolved well to obtain a resin solution mixture having a solid content of 50%.
[0106]
170 parts by weight of a polyester resin (acid value: 14 mg KOH / g) having an acid dissociation group of 0.250 mmol / g, 5 parts by weight of a resin charge control agent (acid value: 28 mg KOH / g) having an acid dissociation group of 0.499 mmol / g, carbon black A raw material in a ratio of 20 parts by weight and 10 parts by weight of wax was put into a Henschel mixer, and the raw material mixed for 10 minutes was melt-kneaded and dispersed at 120 ° C. or less with a Niedix MOS140-800 manufactured by Mitsui Mining Co., Ltd. to obtain a resin mixture. . To 100 parts by weight of this resin mixture, 180 parts by weight of methyl ethyl ketone was added and dissolved well to obtain a resin solution mixture having a solid content of 50%. To 200 parts by weight of this resin solution mixture, 2 parts by weight of 1N ammonia water was added, the rotational speed of the homogenizer was set to 5000 RPM, and 100 parts of deionized water was added dropwise to emulsify and produce particles. Subsequently, methyl ethyl ketone is removed by distillation under reduced pressure, ammonia on the particle surface is neutralized and removed using dilute hydrochloric acid, washed with filtered water, dried, and then volume-average particle diameter 6.8 μm, circularity 0.97. Toner particles were obtained. When the resin charge control agent was produced, a monomer mixture composed of styrene, 2-acrylamido-2-methylpropanesulfonic acid and acrylic acid was used.
[0107]
(Comparative Example 1)
Other than using a resin charge control agent (acid value: 4 mgKOH / g) having an acid dissociation group of 0.070 mmol / g obtained by using a monomer mixture composed of styrene, butyl methacrylate and 2-acrylamido-2-methylpropanesulfonic acid. In the same manner as in Examples 1 to 3, toner particles having a volume average particle diameter of 9.2 μm and a circularity of 0.97 were obtained.
[0108]
(Comparative Example 2)
Other than using a resin charge control agent (acid value: 8 mgKOH / g) having an acid dissociation group of 0.141 mmol / g obtained by using a monomer mixture composed of styrene, butyl methacrylate and 2-acrylamido-2-methylpropanesulfonic acid. In the same manner as in Examples 1 to 3, toner particles having a volume average particle diameter of 7.7 μm and a circularity of 0.97 were obtained.
[0109]
(Comparative Example 3)
Other than using a resin charge control agent (acid value: 4 mgKOH / g) having an acid dissociation group of 0.070 mmol / g obtained by using a monomer mixture composed of styrene, butyl methacrylate and 2-acrylamido-2-methylpropanesulfonic acid. In the same manner as in Example 4, toner particles having a volume average particle diameter of 7.9 μm and a circularity of 0.97 were obtained.
[0110]
(Comparative Example 4)
Other than using a resin charge control agent (acid value: 4 mgKOH / g) having an acid dissociation group of 0.070 mmol / g obtained by using a monomer mixture composed of styrene, butyl methacrylate and 2-acrylamido-2-methylpropanesulfonic acid. In the same manner as in Example 5, toner particles having a volume average particle size of 8.1 μm and a circularity of 0.97 were obtained.
[0111]
(Comparative Example 5)
Other than using a resin charge control agent (acid value: 4 mgKOH / g) having an acid dissociation group of 0.070 mmol / g obtained by using a monomer mixture composed of styrene, butyl methacrylate and 2-acrylamido-2-methylpropanesulfonic acid. In the same manner as in Example 6, toner particles having a volume average particle size of 9.0 μm and a circularity of 0.97 were obtained.
[0112]
(Comparative Example 6)
The volume average particle diameter was the same as in Example 2 except that an acidic dissociable group 0.450 mmol / g acrylic resin obtained by using a monomer mixture consisting of styrene, methacrylic acid, methyl methacrylate, and methacrylate-n-butyl was used. Toner particles having a diameter of 7.0 μm and a circularity of 0.97 were obtained.
[0113]
(Comparative Example 7)
The volume average particle size is 7.0 μm and the circularity is 0.00, as in Example 1, except that 0.05 part by weight of a resin charge control agent (acid value: 21 mg KOH / g) having an acid dissociable group of 0.374 mmol / g is used. 97 toner particles were obtained.
[0114]
(Comparative Example 8)
A volume average particle size of 6.0 μm and a circularity of 0.97 was obtained in the same manner as in Example 1 except that the resin charge control agent (acid value: 21 mg KOH / g) having an acid dissociation group of 0.374 mmol / g was 30 parts by weight. Toner particles were obtained.
[0115]
[Characteristic evaluation]
For each of the above-mentioned Examples and Comparative Examples, the obtained toner was mixed and stirred at a ratio of 3 parts by weight to 97 parts by weight of a ferrite carrier having an average particle diameter of 60 μm to prepare a two-component developer. Confirmed environmental stability. The charge amount was measured under the environmental conditions of 20 ° C. and 50% RH normal temperature and normal humidity, and 35 ° C. and 80% RH high temperature and high humidity, and the charge amount ratios in the normal temperature and normal humidity / high temperature and high humidity environment were compared.
[0116]
Further, a developer is prepared using these toners, and using “AR-C150” (manufactured by Sharp), the toner adhesion amount is 0 on the “full-color exclusive paper” (manufactured by Sharp, product number: PP106A4C). .8mg / cm ² An image sample was prepared using an external fixing machine.
[0117]
The evaluation of the image sample was performed as follows. The transfer rate was calculated from the toner weight Mp on the paper surface of the sample copied on the predetermined chart and the toner weight Md remaining on the photoconductor.
[0118]
The transfer rate is obtained by the following equation.
Transfer rate = (100 × Mp) / (Md + Mp)
The optical density of the image sample was measured with an “X-Rite 938 spectrocolorimetric densitometer” (manufactured by Nippon Planographic Printing Equipment Co., Ltd.).
[0119]
When the white background fog of the image sample is black toner, the whiteness of the A4 size special paper is measured in advance with a “whiteness meter” (manufactured by Nippon Denshoku Industries Co., Ltd.), and the measured value is the first measured value And Next, using a manuscript including a white circle with a diameter of 55 mm, three copies are made, and the white portion of the obtained copy sample is measured with the whiteness meter, and this value is set as the second measurement value. A value obtained by subtracting the second measurement value from the first measurement value is defined as a fogging value. In the case of color toner, the determination was made visually.
The results of each evaluation are shown in Table 1.
[0120]
[Table 1]

[0121]
As a result of the evaluation based on the evaluation criteria described above, as shown in Table 1, the number of gram equivalents of acidic dissociation groups per unit weight of the resin charge control agent that satisfies the conditions of the present invention is not water-soluble. Examples 1 to 6, which are more than the number of gram equivalents of acid dissociable groups per unit weight of the resin, are acceptable and do not meet the conditions of the present invention, that is, grams of acid dissociable groups per unit weight of the resin charge control agent. It was found that Comparative Examples 1 to 8 in which the number of equivalents was less than the number of gram equivalents of acidic dissociable groups per unit weight of the water-insoluble resin were unacceptable.
[0122]
【The invention's effect】
When the toner production method according to the present invention is used, the number of gram equivalents of acidic dissociable groups per unit weight of the resin charge control agent is larger than the number of gram equivalents of acidic dissociable groups per unit weight of the water-insoluble resin. In addition, the resin charge control agent can be efficiently and uniformly contained in the toner resin, the charge control agent can be used efficiently when the toner is manufactured, and the concentration of the charge control agent contained can be adjusted. Accordingly, when an image is formed using this toner, a good image can be obtained without fogging and image density unevenness.

Claims (7)

The colorant and the resin charge control agent are contained by emulsifying, in an aqueous solution, a mixture containing at least one water-insoluble resin having an acid dissociable group, a colorant, and a resin charge control agent as essential components. In addition, in the method for producing a toner obtained by separating the water-insoluble resin particles after drying the water-insoluble resin particles and drying the particles, the resin charge control agent contains at least a sulfonic acid group as a monomer. A monomer is included as a structural unit, and the number of gram equivalents of acidic dissociable groups per unit weight of the resin charge control agent is greater than the number of gram equivalents of acidic dissociable groups per unit weight of the water-insoluble resin. Toner manufacturing method. At least one water-insoluble resin having an acid dissociable group, a colorant, and the number of gram equivalents of acid dissociable groups per unit weight are more than the number of gram equivalents of acid dissociable groups per unit weight of the water-insoluble resin. A step of obtaining a mixture containing a large amount of resin charge control agent as an essential component by heating and melting;
Emulsifying the mixture obtained in the step in an aqueous solution to produce particles of the water-insoluble resin containing the resin charge control agent and the colorant;
The method for producing a toner according to claim 1, further comprising a step of separating the water-insoluble resin particles produced in the step from water and drying the particles. At least one water-insoluble resin having an acid dissociable group, a colorant, and the number of gram equivalents of acid dissociable groups per unit weight are more than the number of gram equivalents of acid dissociable groups per unit weight of the water-insoluble resin. A step of obtaining a mixture containing a large amount of resin charge control agent as an essential component by using an organic solvent that dissolves the resin and the resin charge control agent;
Emulsifying the mixture obtained in the step in an aqueous solution to produce particles of the water-insoluble resin containing the resin charge control agent and the colorant;
The method for producing a toner according to claim 1, further comprising a step of separating the water-insoluble resin particles produced in the step from water and drying the particles.   4. The method for producing a toner according to claim 1, wherein the water-insoluble resin is at least one resin selected from polyesters.   The method for producing a toner according to claim 1, wherein the dissociating group of the water-insoluble resin includes a carboxyl group. Method for producing a toner according to any one of claims 1 to 5, characterized in that to contain 0.1 to 20% by weight of the resin charge controlling agent to the toner particles. The colorant, black, cyan, yellow, and method for producing a toner according to any one of claims 1 to 6, characterized in that it comprises one or more colorants magenta.