JP2021124654A - toner - Google Patents

Abstract

To obtain a toner that can output an image without gloss unevenness and is excellent in developability and storage stability.SOLUTION: A toner has a toner particle containing a binder resin, a crystalline resin, hydrocarbon wax, and a colorant. A weight average molecular weight of the crystalline resin is 1000 or more and 4500 or less, and a difference in Hansen solubility parameter between the crystalline resin and the hydrocarbon wax is 2.5 or less.SELECTED DRAWING: None

Description

The present invention relates to toners used in electrophotographic methods.

In recent years, image forming devices such as copiers and printers are required to have both energy saving and image quality as the purpose of use and the environment of use are diversified. From the viewpoint of improving energy saving, first of all, toner having further improved low temperature fixability can be mentioned.
Crystalline materials such as wax and crystalline resin are used to improve the low temperature fixability of the toner. The crystalline material melts at the melting point of the material, plasticizes the binder resin of the toner, and promotes the melt deformation of the toner.
If the melting characteristics of the toner vary with the improvement of the fixability, the gloss may fluctuate greatly and gloss unevenness may occur. Gross unevenness is easily noticeable in images with a high printing rate, and improvement is required in order to meet the ever-increasing demand for print quality.
Further, in the process of improving the melting characteristics, lowering the melting temperature itself is often used as a means. In that case, the storage stability of the toner is often impaired when it is assumed that the toner is used in various environments. Improvement of storage stability is required to use the printer stably regardless of the environment.
Many techniques have been disclosed conventionally for the above problems (for example, Patent Document 1 and Patent Document 2). However, even with these proposed toners, they are insufficient in terms of high developability, suppression of gloss unevenness, and storage stability, and improvement is required.

Japanese Unexamined Patent Publication No. 2017-111283 JP-A-2007-114627

An object of the present invention is to obtain a toner which can output an image without gloss unevenness and which is excellent in developability and storage stability.

The present invention is a toner containing toner particles having a binder resin, a crystalline resin, a hydrocarbon wax, and a colorant.
The crystalline resin has a weight average molecular weight of 1000 or more and 4500 or less.
The present invention relates to a toner characterized in that the difference in solubility parameter between the crystalline resin and Hansen of the hydrocarbon wax is 2.5 or less.

According to the present invention, it is possible to output an image without gloss unevenness, and to obtain a toner having excellent developability and storage stability.

Hereinafter, embodiments for carrying out the present invention will be described in detail.

The present invention is a toner containing toner particles having a binder resin, a crystalline resin, a hydrocarbon wax, and a colorant.
The crystalline resin has a weight average molecular weight of 1000 or more and 4500 or less.
The toner is characterized in that the difference in solubility parameter between the crystalline resin and Hansen of the hydrocarbon wax is 2.5 or less.

Here, the gross unevenness will be described based on the examination by the present inventors. Gloss unevenness occurs when an image having a high printing rate such as a solid image is output, and a portion having a high gloss and a portion having a low gloss are formed. The gloss is high when the toner on the image is melted to produce a smooth surface, and is low when the shape of the toner particles remains because the reflected light is reduced. That is, it is important how to make the amount of toner deformation on the image uniform.

In the studies by the present inventors, the behavior of the crystalline resin has a large effect on the amount of deformation, and has a high effect of greatly improving the gloss and improving the fixability. However, the adverse effect on the storage stability is large, and if the crystalline resin is unevenly dispersed, it directly leads to gloss unevenness.

Further studies have found that by adjusting the relationship between the material properties so that the crystalline resin and the hydrocarbon wax are mixed better, the fixability, storage stability, and gloss unevenness are dramatically improved, and the present invention has been made. I arrived. Hereinafter, the contents of the present invention will be specifically described.

Hereinafter, preferred embodiments of the toner of the present invention will be described.

The toner of the present invention contains a hydrocarbon wax and a crystalline resin. This is because when a crystal in which both are mixed (hereinafter, also referred to as a eutectic or a composite crystal) is formed, there is an effect of significantly improving the problem of the present invention, which is an essential material for the present invention. Is. The crystallinity in the present invention refers to a material having an endothermic peak in differential scanning calorimetry (hereinafter, also referred to as DSC measurement) of a single material.

Further, the crystalline resin in the present invention satisfies the following conditions. In the DSC measurement, the temperature is once raised to 180 ° C. (1 ^st- run) and then raised to 180 ° C. again (2 ^nd- run). At that time, the endothermic peak temperature Tm1 obtained in 1 ^st -run, temperature difference Tm1-Tm2 endothermic peak temperature Tm2 obtained in 2 ^nd -run is a crystalline resin what is 1.5 ° C. or higher .. For example, a high molecular weight ester wax such as dipentaerythritol tetrabehenate has a Tm1-Tm2 of less than 1 ° C. as measured above and is not contained in the crystalline resin.

Next, the crystalline resin contained in the toner of the present invention has a weight average molecular weight of 1000 or more and 4500 or less. Preferably, it is 1000 or more and 3500 or less. This is because, in the toner manufacturing process, when it is 1000 or more and 4500 or less, the gloss unevenness tends to be excellently suppressed.

If the weight average molecular weight of the crystalline resin is 1000 or more and 4500 or less and the solubility parameter range described later is satisfied, eutectic can be formed with the hydrocarbon wax. Conventionally, crystalline resin and hydrocarbon wax are difficult to mix and often exist independently inside the toner. Therefore, it is difficult to uniformly exist in the toner, and a portion where the crystalline resin is compatible with the binder resin and a portion where it is difficult to proceed are formed. When present as eutectic, since the hydrocarbon wax and the crystalline resin are present at the same location, unevenness in the toner such as a portion containing a large amount of hydrocarbon wax or a portion containing a large amount of crystalline resin can be made very small. Therefore, melting unevenness at the time of heat fixing is eliminated, and gloss unevenness is significantly reduced. Further, even if the storage stability is deteriorated due to the crystalline resin having a low crystallinity, the surface exudation with time is suppressed by the eutectic with the hydrocarbon, and the storage stability is greatly improved.

It is essential to adjust the solubility parameter of the crystalline resin and the hydrocarbon wax of the present invention, and by increasing the affinity between the two, the miscibility is improved and eutectic crystals are formed. There are various calculation methods for the solubility parameter, but in the present invention, the polarity term of the Hansen solubility parameter is used. This is because it correlates well with the affinity between the crystalline resin and the hydrocarbon wax, and a small difference in polar terms indicates a high affinity. Specifically, when the difference in the solubility parameter of Hansen is 2.5 or less, gloss unevenness suppression, storage stability, and developability are significantly improved. If it exceeds 2.5, the affinity between the hydrocarbon wax and the crystalline resin decreases, and each of them exists independently inside the toner. Therefore, the gloss unevenness is significantly deteriorated due to uneven exudation and deformation during heat fixing. In addition, the hydrocarbon wax and the crystalline resin exude to the surface over time, and the storage stability and the development stability are greatly deteriorated.

The toner of the present invention uses a hydrocarbon wax and a crystalline resin as described above, and the hydrocarbon is obtained only by controlling the relationship between the solubility parameters of the hydrocarbon wax and the crystalline resin and the molecular weight of the crystalline resin. The affinity between wax and crystalline resin is greatly increased. As a result, eutectic crystals are formed, and unevenness is less likely to occur in the presence state of the hydrocarbon wax during heat fixing, and the melting condition of the image becomes uniform, so that gloss unevenness is significantly reduced. Further, when the crystalline resin and the hydrocarbon wax are mixed to form crystals, the crystalline resin or the hydrocarbon wax with time is more likely to gather and crystallize, and the phenomenon of exuding to the toner surface is less likely to occur. As a result, storage stability is greatly improved. In addition, since the surface composition is unlikely to change, the development stability during long-term use is greatly improved.

In the toner of the present invention, it is preferable that the difference in crystallization temperature between the hydrocarbon wax and the crystalline resin is 2 ° C. or more, and the hydrocarbon wax and the crystalline resin form eutectic inside the toner. When the crystallization temperature of the hydrocarbon wax and the crystalline resin is 2 ° C. or higher, the stability with time tends to be further enhanced when eutectic is formed, and it is more preferable that the crystallization temperature is 7 ° C. or higher. Further, forming a eutectic tends to suppress gloss unevenness, improve storage stability, and enhance development stability, which is preferable.

The eutectic in the present invention refers to a state in which two or more crystalline substances having different cold crystallization peak temperatures are crystallized in a mixed state. Therefore, in the present invention, the presence or absence of eutectic is determined by observing the cold crystallization peak at the time of temperature decrease in the DSC curve measured by the differential scanning calorimeter and determining whether or not the cold crystallization peak exists at a temperature different from that of the simple substance. .. As a criterion, if the peak area of the eutectic is 10% or more with respect to the total area of the cold crystallization peak, the eutectic is considered to exist.

Next, the weight average molecular weight of the hydrocarbon wax used in the toner of the present invention is preferably 300 or more and 2000 or less. As described above, the molecular weight of the crystalline resin is effective for the ease of mixing the hydrocarbon wax and the crystalline resin, but the molecular weight of the hydrocarbon wax is also affected. The above range is preferable because it is easy to mix with the crystalline resin and the storage stability is particularly improved.

The crystalline resin used for the toner of the present invention will be described.

The crystalline resin is preferably crystalline polyester. This is because it is easy to control the ease of mixing with the above-mentioned hydrocarbon wax and the state of existence inside the toner.

Further, the crystalline polyester is preferably a condensate of an aliphatic dicarboxylic acid and an aliphatic diol from the viewpoint of easily forming a eutectic with a hydrocarbon wax.

Further, according to the studies by the present inventors, the aliphatic diol preferably has 7 or more carbon atoms, and the aliphatic dicarboxylic acid preferably has 12 or more carbon atoms. This is preferable because the effect of forming the above-mentioned eutectic system is enhanced, and the storage stability tends to be improved.

As a method for producing the toner, it is preferable that the method for producing the toner particles includes a step of mixing the hydrocarbon wax and the crystalline resin in a molten state. In the toner of the present invention, how to mix the hydrocarbon wax and the crystalline resin to form a eutectic is very important. Therefore, it is preferable to have a step of mixing after melting because the mixing is promoted. More preferably, the toner particles are produced by a suspension polymerization method.

The solubility parameter of Hansen of the crystalline resin of the present invention is preferably 2.5 or less, more preferably 2.1 or less, from the viewpoint of eutectic formation with the hydrocarbon wax. Further, the solubility parameter of Hansen of the hydrocarbon wax is preferably 0.1 or less from the viewpoint of eutectic formation with the crystalline resin.

Next, the material composition and the manufacturing method that can be used for the toner of the present invention will be described in detail.

Any crystalline resin can be used, but a crystalline polyester resin is preferable.

The raw material monomer of the crystalline polyester resin is not particularly limited as long as it does not lose its crystallinity, and any monomer can be used. As the alcohol component of the crystalline polyester resin, it is preferable to use an aliphatic diol having 7 or more carbon atoms from the viewpoint of enhancing crystallinity, and a structure having hydroxyl groups at both ends of the linear alkylene group is preferable. Aliphatic diols having 7 or more carbon atoms include 1,7-heptane diol, 1,8-octane diol, 1,9-nonane diol, 1,10-decane diol, 1,11-undecane diol, and 1,12-. Dodecanediol and the like can be mentioned. The content of the aliphatic diol is preferably 80.0 mol% or more and 100.0 mol% or less in the alcohol component from the viewpoint of further enhancing the crystallinity of the crystalline polyester resin.

As the alcohol component for obtaining the crystalline polyester resin, a polyhydric alcohol component other than the above-mentioned aliphatic diol may be contained. For example, an alkylene oxide adduct of bisphenol A containing a polyoxypropylene adduct of 2,2-bis (4-hydroxyphenyl) propane, a polyoxyethylene adduct of 2,2-bis (4-hydroxyphenyl) propane, and the like. Aromatic diols; glycerin, pentaerythritol, trimethylolpropane and other trihydric or higher alcohols.

As the carboxylic acid component used in the raw material monomer of the crystalline polyester resin, it is preferable to use an aliphatic dicarboxylic acid compound having 12 or more carbon atoms, and a structure having carboxyl groups at both ends of the linear alkylene group is preferable. Examples of the aliphatic dicarboxylic acid compound having 12 or more carbon atoms include 1,10-dodecanedioic acid, 1,12-tetradecanedioic acid, and 1,14-hexadecanedioic acid. The content of the aliphatic dicarboxylic acid compound is preferably 80.0 mol% or more and 100.0 mol% or less in the carboxylic acid component.

The carboxylic acid component for obtaining the crystalline polyester resin may contain a carboxylic acid component other than the above-mentioned aliphatic dicarboxylic acid compound. For example, an aromatic dicarboxylic acid compound, a trivalent or higher aromatic polyvalent carboxylic acid compound, and the like can be mentioned, but the present invention is not particularly limited thereto. Aromatic dicarboxylic acid compounds also include aromatic dicarboxylic acid derivatives. Specific examples of the aromatic dicarboxylic acid compound include aromatic dicarboxylic acids such as phthalic acid, isophthalic acid and terephthalic acid, anhydrides of these acids, and alkyl (carbon atoms 1 to 3) esters thereof. .. Examples of the alkyl group in the alkyl ester include a methyl group, an ethyl group, a propyl group and an isopropyl group. Examples of the trivalent or higher valent carboxylic acid compound include aromatic carboxylic acids such as 1,2,4-benzenetricarboxylic acid (trimellitic acid), 2,5,7-naphthalenetricarboxylic acid, and pyromellitic acid, and these. Derivatives such as acid anhydrides and alkyl (1 or more and 3 or less carbon atoms) esters can be mentioned.

It is preferable to control the acid value (mgKOH / g) of the crystalline polyester to be low from the viewpoint of increasing the plasticity of the crystalline polyester. Specifically, it is 8.0 or less. It is more preferably 5.0 or less, still more preferably 4.5 or less.

In the toner of the present invention, a crystalline polyester and an amorphous polyester can be used in combination. This is expected to be effective not as a binder resin but as a shell layer, for example. The amorphous polyester is preferably contained in an amount of 1.0 part by mass or more, more preferably 1.0 part by mass or more and 20.0 parts by mass or less, based on 100 parts by mass of the binder resin.

The toner of the present invention contains a hydrocarbon wax. Hydrocarbon wax is known to crystallize in the form of stacked linear hydrocarbon chain portions, and examples thereof include paraffin wax and Fischer-Tropsch wax.

As the hydrocarbon wax that can be used in the present invention, hydrocarbon waxes such as low molecular weight polyethylene, low molecular weight polypropylene, microcrystalline wax, and paraffin wax are preferable from the viewpoint of high releasability. If necessary, two or more kinds of waxes may be used together.

Specific examples of the wax include the following. Sazole H1, H2, C80, C105, C77 (Schumann Sazol), HNP-1, HNP-3, HNP-9, HNP-10, HNP-11, HNP-12 (Nippon Seikan Co., Ltd.).

In the present invention, a wax containing a fatty acid ester as a main component (hereinafter referred to as ester wax) can also be used in combination. However, in the present invention, it is preferable that the hydrocarbon wax is the main component (the main component refers to a component that occupies 80% or more of the total amount of wax).

The toner of the present invention can contain the binder resin in any kind and ratio. As the binder resin, any resin such as styrene acrylic resin, polyester resin, urethane resin and the like can be used. Here, it is preferable that the difference in the polarity term of the solubility parameter of Hansen of the binder resin and the crystalline resin is 1.6 or less. This is because, within this range, the binder resin and the crystalline resin are easily phase-separable, the crystal growth of the crystalline resin inside the toner is promoted, and the storage stability tends to be improved.

As the toner particles that can be used in the present invention, any of known production methods such as a dry method, an emulsion polymerization method, a dissolution turbidity method, and a suspension polymerization method can be used. However, from the viewpoint of developability, the toner is preferably spherical, surface modification treatment such as thermal spheroidization treatment is preferable in the dry method, and suspension polymerization method is preferable in the polymerization method, and particularly preferably in an aqueous medium. This is a suspension polymerization method in which a polymerizable monomer composition is granulated in 1 and the particles of the polymerizable monomer composition are formed.

Hereinafter, a particularly preferable suspension polymerization method will be described in detail.

As the polymerizable monomer for the binder resin of the toner, a vinyl-based monomer capable of radical polymerization is used. As the vinyl-based monomer, a monofunctional monomer or a polyfunctional monomer can be used.

Monofunctional monomers include styrene; styrene derivatives such as α-methylstyrene, β-methylstyrene, ο-methylstyrene, m-methylstyrene, p-methylstyrene, p-methoxystyrene, p-phenylstyrene; methyl. Acrylic polymerizable monomers such as acrylates, ethyl acrylates, n-propyl acrylates, iso-propyl acrylates, n-butyl acrylates, dibutyl phosphate ethyl acrylates, 2-benzoyloxyethyl acrylates; methyl methacrylate, ethyl methacrylate, dibutyl Methacrylic polymerizable monomers such as phosphate ethyl methacrylate; Methylene aliphatic monocarboxylic acid esters; Vinyl esters such as vinyl acetate and vinyl propionate; Vinyl ethers such as vinyl methyl ether, vinyl ethyl ether and vinyl isobutyl ether Examples include vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone, vinyl isopropyl ketone.

Among the above, the polymerizable monomer preferably contains styrene or a styrene derivative.

Examples of the polyfunctional monomer include diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol diacrylate, tetramethylolmethanetetramethacrylate, divinylbenzene, and divinyl ether.

The above-mentioned monofunctional monomers may be used alone or in combination of two or more, or the above-mentioned monofunctional monomers and polyfunctional monomers may be used in combination. The polyfunctional monomer can also be used as a cross-linking agent.

As the polymerization initiator that can be used in the present invention, an oil-soluble initiator and / or a water-soluble initiator is used. Preferably, the half-life at the reaction temperature during the polymerization reaction is 0.5 hours or more and 30 hours or less. Further, when the polymerization reaction is carried out with an addition amount of 0.5 parts by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the polymerizable monomer, a polymer having a maximum value between 10,000 parts by mass and 100,000 parts or less usually has a molecular weight. It is preferable because the obtained toner particles having appropriate strength and melting characteristics can be obtained.

Examples of the polymerization initiator include the following 2,2'-azobis- (2,4-dimethylvaleronitrile), 2,2'-azobisisobutyronitrile, and 1,1'-azobis (cyclohexane-1-carbo). Azo-based or diazo-based polymerization initiators such as nitrile), 2,2'-azobis-4-methoxy-2,4-dimethylvaleronitrile, azobisisobutyronitrile; benzoyl peroxide, t-butylperoxy2- Ethylhexanoate, t-butylperoxypivalate, t-butylperoxyisobutyrate, t-butylperoxyneodecanoate, methylethylketone peroxide, diisopropylperoxycarbonate, cumenehydroperoxide, 2,4- Examples thereof include peroxide-based polymerization initiators such as dichlorobenzoyl peroxide and lauroyl peroxide.

In the present invention, in order to control the degree of polymerization of the polymerizable monomer, it is also possible to further add and use a known chain transfer agent, polymerization inhibitor and the like.

In the present invention, the polymerizable monomer composition may contain a polyester resin. Examples of the polyester resin that can be used in the present invention include the following.

Examples of the divalent acid component include the following dicarboxylic acids or derivatives thereof. Benzenedicarboxylic acids such as phthalic acid, terephthalic acid, isophthalic acid, phthalic anhydride or its anhydrides or lower alkyl esters thereof; alkyldicarboxylic acids such as succinic acid, adipic acid, sebacic acid, azelaic acid or its anhydrides or lower thereof Alkyl esters; alkenyl succinic acids or alkyl succinic acids such as n-dodecenyl succinic acid, n-dodecyl succinic acid, or anhydrides thereof or lower alkyl esters thereof; unsaturated dicarboxylic acids such as fumaric acid, maleic acid, citraconic acid, itaconic acid. Or its anhydride or its lower alkyl ester.

Examples of the divalent alcohol component include the following. Ethylene glycol, polyethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,6-hexanediol, neopentyl glycol, 1,4-cyclohexanedimethanol (CHDM), hydride bisphenol A, bisphenol and the like. Derivative.

The polyester resin that can be used in the present invention includes a monovalent carboxylic acid compound, a monovalent alcohol compound, a trivalent or higher carboxylic acid compound, and 3 in addition to the above-mentioned divalent carboxylic acid compound and divalent alcohol compound. An alcohol compound having a value or higher may be contained as a constituent component.

Examples of the monovalent carboxylic acid compound include aromatic carboxylic acids having 30 or less carbon atoms such as benzoic acid and p-methylbenzoic acid, and aliphatic carboxylic acids having 30 or less carbon atoms such as stearic acid and behenic acid. ..

Examples of the monohydric alcohol compound include aromatic alcohols having 30 or less carbon atoms such as benzyl alcohol, and fatty alcohols having 30 or less carbon atoms such as lauryl alcohol, cetyl alcohol, stearyl alcohol, and behenyl alcohol. Be done.

The carboxylic acid compound having a trivalent or higher valence is not particularly limited, and examples thereof include trimellitic acid, trimellitic anhydride, and pyromellitic acid.

Examples of the trihydric or higher alcohol compound include trimethylolpropane, pentaerythritol, and glycerin.

The method for producing the polyester resin that can be used in the present invention is not particularly limited, and a known method can be used.

The amorphous polyester is preferably contained in an amount of 1.0 part by mass or more, more preferably 1.0 part by mass or more and 20.0 parts by mass or less, based on 100 parts by mass of the binder resin.

The toner of the present invention contains a colorant, but any colorant can be used. When applied to a monochrome toner, a colorant such as carbon black or a magnetic material can be used, but a magnetic material is particularly preferable. This is because the interaction with the crystalline resin is small and it is easy to control the existence state of the crystalline resin.

The magnetic material is mainly composed of magnetic iron oxide such as triiron tetraoxide and γ-iron oxide, and may contain elements such as phosphorus, cobalt, nickel, copper, magnesium, manganese, aluminum and silicon. These magnetic powders preferably have a BET specific surface area of 2 to 30 m ² / g by the nitrogen adsorption method, and more preferably 3 to 28 m ² / g. Further, those having a Mohs hardness of 5 to 7 are preferable. The shape of the magnetic powder includes a polyhedron, an octahedron, a hexahedron, a sphere, a needle, and a scaly shape. It is preferable to enhance it.

The magnetic powder preferably has a number average particle size of 0.10 to 0.40 μm. Generally, the smaller the particle size of the magnetic powder, the higher the coloring power, but the magnetic powder tends to aggregate. Therefore, the above range is preferable from the viewpoint of the balance between the coloring power and the cohesiveness.

The number average particle size of the magnetic powder can be measured using a transmission electron microscope. Specifically, after the toner particles to be observed are sufficiently dispersed in the epoxy resin, the cured product is obtained by curing in an atmosphere at a temperature of 40 ° C. for 2 days. The obtained cured product is used as a flaky sample by a microtome, and the diameters of 100 magnetic powder particles in the field of view are measured with a transmission electron microscope (TEM) at a magnification of 10,000 to 40,000 times. Then, the number average particle diameter is calculated based on the equivalent diameter of the circle equal to the projected area of the magnetic powder. It is also possible to measure the particle size with an image analyzer.

The magnetic powder used for the toner of the present invention can be produced, for example, by the following method. An aqueous solution containing ferrous hydroxide is prepared by adding an equal amount or more of an alkali such as sodium hydroxide to the iron component to the ferrous salt aqueous solution. Air is blown while maintaining the pH of the prepared aqueous solution at pH 7 or higher, and the ferrous hydroxide oxidation reaction is carried out while heating the aqueous solution to 70 ° C. or higher to first form seed crystals that are the core of the magnetic iron oxide powder. Generate.

Next, an aqueous solution containing about 1 equivalent of ferrous sulfate is added to the slurry-like liquid containing seed crystals based on the amount of alkali added previously. While maintaining the pH of the liquid at 5 to 10, the reaction of ferrous hydroxide is promoted while blowing air, and the magnetic iron oxide powder is grown around the seed crystal. At this time, the shape and magnetic properties of the magnetic powder can be controlled by selecting an arbitrary pH, reaction temperature, and stirring conditions. As the oxidation reaction progresses, the pH of the liquid shifts to the acidic side, but it is preferable that the pH of the liquid is not less than 5. The magnetic material thus obtained can be obtained by filtering, washing and drying the magnetic material by a conventional method.

Further, in the case of producing toner in an aqueous medium in the present invention, it is very preferable to hydrophobize the surface of the magnetic powder. When surface treatment is performed by the dry method, the magnetic powder that has been washed, filtered, and dried is treated with a coupling agent. When the surface treatment is performed wet, the dried iron oxide is redispersed after the oxidation reaction is completed, or the iron oxide obtained by washing and filtering after the oxidation reaction is completed in another aqueous medium without drying. Is redistributed and the coupling process is performed. In the present invention, both the dry method and the wet method can be appropriately selected.

Examples of the coupling agent that can be used in the surface treatment of the magnetic powder in the present invention include a silane coupling agent and a titanium coupling agent. More preferably used is a silane coupling agent, which is represented by the general formula (I).
R _m SiY _n (I)
[In the formula, R represents an alkoxy group, m represents an integer of 1 to 3, Y represents a functional group such as an alkyl group, a vinyl group, an epoxy group, or a (meth) acrylic group, and n represents a functional group of 1 to 3. Indicates an integer. However, m + n = 4. ]

In the present invention, those in which Y of the general formula (I) is an alkyl group can be preferably used. Of these, an alkyl group having 3 or more and 6 or less carbon atoms is preferable, and 3 or 4 is particularly preferable.

When the above silane coupling agent is used, it can be treated alone or in combination of a plurality of types. When a plurality of types are used in combination, they may be treated individually with each coupling agent or may be treated at the same time.

The total amount of the coupling agent to be treated is preferably 0.9 parts by mass or more and 3.0 parts by mass or less with respect to 100 parts by mass of the magnetic powder, and the surface area of the magnetic powder, the reactivity of the coupling agent, etc. It is important to adjust the amount of treatment agent accordingly.

In the present invention, other colorants may be used in combination with the magnetic powder. Examples of the colorant that can be used in combination include the above-mentioned known dyes and pigments, as well as magnetic or non-magnetic inorganic compounds. Specifically, ferromagnetic metal particles such as cobalt and nickel, or alloys obtained by adding chromium, manganese, copper, zinc, aluminum, rare earth elements, and the like to these. Particles such as hematite, titanium black, niglosin dye / pigment, carbon black, phthalocyanine and the like can be mentioned. These are also preferably surface-treated and used.

The content of the magnetic powder in the toner can be measured using a thermal analyzer manufactured by PerkinElmer, TGA7. The measurement method is as follows. The toner is heated from room temperature to 900 ° C. at a heating rate of 25 ° C./min in a nitrogen atmosphere. The weight loss mass% between 100 ° C. and 750 ° C. is defined as the amount of binder resin, and the residual mass is approximately defined as the amount of magnetic powder.

In the method for producing toner particles by the suspension polymerization method, in addition to the above-mentioned materials, known charge control agents, conductivity-imparting agents, lubricants, abrasives and the like may be added.

After the polymerization of the toner particles obtained as described above is completed, the toner particles are filtered, washed, and dried by a known method, and if necessary, an inorganic fine powder as a fluidity improver is mixed and adhered to the surface of the toner. Can be obtained.

As the inorganic fine powder, known ones can be used. Preferably, silica fine particles such as titania fine particles, wet manufacturing silica, and dry silica, and inorganic fine powder obtained by surface-treating the silica with a silane coupling agent, a titanium coupling agent, silicone oil, or the like.

Next, the material used for the toner, the toner particles, and the method for measuring the toner are as shown below. In the examples described later, the physical property values are measured based on these methods.

<Measuring method of weight average particle size (D4) and number average particle size (D1)>
The weight average particle size (D4) and the number average particle size (D1) of the toner are the precision particle size distribution measuring device "Coulter Counter Multisizer 3" (registered trademark, Beckman.) By the pore electric resistance method equipped with an aperture tube of 100 μm. Using Coulter) and the attached dedicated software "Beckman Coulter Multisizer 3 Version 3.51" (Beckman Coulter) for setting measurement conditions and analyzing measurement data, the number of effective measurement channels is 25,000. The measurement was performed on the channel, and the measurement data was analyzed and calculated.

As the electrolytic aqueous solution used for the measurement, a special grade sodium chloride dissolved in ion-exchanged water so as to have a concentration of about 1% by mass, for example, "ISOTON II" (manufactured by Beckman Coulter) can be used.

Before the measurement and analysis, the dedicated software was set as follows.

In the dedicated software "Change standard measurement method (SOM) screen", set the total count number in the control mode to 50,000 particles, measure once, and set the Kd value to "standard particles 10.0 μm" (Beckman Coulter). The value obtained using (manufactured by) is set. By pressing the threshold / noise level measurement button, the threshold and noise level are automatically set. Also, set the current to 1600 μA, the gain to 2, and the electrolyte to ISOTON II, and check the flush of the aperture tube after measurement.

On the "pulse to particle size conversion setting screen" of the dedicated software, the bin spacing is set to logarithmic particle size, the particle size bin is set to 256 particle size bins, and the particle size range is set from 2 μm to 60 μm.

The specific measurement method is as follows.
1. 1. Approximately 200 ml of the electrolytic aqueous solution is placed in a glass 250 ml round bottom beaker dedicated to the Multisizer 3 and set on a sample stand, and the stirrer rod is stirred counterclockwise at 24 rpm. Then, the dirt and air bubbles in the aperture tube are removed by the "aperture flash" function of the analysis software.
2. Approximately 30 ml of the electrolytic aqueous solution is placed in a 100 ml flat-bottomed beaker made of glass, and "Contaminone N" (nonionic surfactant, anionic surfactant, organic builder) is used as a dispersant for cleaning a precision measuring instrument at pH 7. Add about 0.3 ml of a diluted solution obtained by diluting a 10% by mass aqueous solution of a neutral detergent (manufactured by Wako Pure Chemical Industries, Ltd.) with ion-exchanged water 3 times by mass.
3. 3. Two oscillators with an oscillation frequency of 50 kHz are built in with the phase shifted by 180 degrees, and a predetermined amount of ions are contained in the water tank of the ultrasonic disperser "Ultrasonic Dispersion System Tetora 150" (manufactured by Nikkaki Bios) with an electrical output of 120 W. Exchange water is added, and about 2 ml of the Contaminone N is added into the water tank.
4. 2. Is set in the beaker fixing hole of the ultrasonic disperser, and the ultrasonic disperser is operated. Then, the height position of the beaker is adjusted so that the resonance state of the liquid level of the electrolytic aqueous solution in the beaker is maximized.
5. 4. With the electrolytic aqueous solution in the beaker irradiated with ultrasonic waves, about 10 mg of toner is added little by little to the electrolytic aqueous solution and dispersed. Then, the ultrasonic dispersion processing is continued for another 60 seconds. In ultrasonic dispersion, the water temperature in the water tank is appropriately adjusted to be 10 ° C. or higher and 40 ° C. or lower.
6. The above 1. installed in the sample stand. Toner was dispersed in a round-bottomed beaker using a pipette. The aqueous electrolyte solution of No. 1 is added dropwise to adjust the measured concentration to about 5%. Then, the measurement is performed until the number of measurement particles reaches 50,000.
7. The measurement data is analyzed by the dedicated software attached to the device, and the weight average particle size (D4) and the number average particle size (D1) are calculated. In addition, when the graph / number% and graph / volume% are set by the dedicated software, the "arithmetic diameter" on the analysis / number statistical value (arithmetic mean) and analysis / volume statistics (arithmetic mean) screens is the number average. The particle size (D1) and the weight average particle size (D4).

<Hansen solubility parameter>
HSP is a three-dimensional vector quantity consisting of a dispersion term, a polarity term, and a hydrogen bond term. In the present invention, the polar term is used.

The difference in HSP is a calculated value showing the ease of dissolving a solute in a solvent or the ease of mixing a plurality of solvents from the viewpoint of intermolecular interaction. It is presumed that the closer the difference in HSP between the two substances is to 0, the higher the affinity of those substances, and the higher the solubility and miscibility.

The HSP is included in the database of the calculation software "Hansen Solubility Parameter in Practice (HSPiP) Version 4.1.03" (written by Steven Abbott, Charles M. Hansen, Hiroshi Yamamoto). Further, the HSP of wax is calculated by inputting the chemical structural formula of wax using the calculation software. The HSP of the hydrocarbon wax is calculated by inputting the structure of the linear alkane closest to the weight average molecular weight of the hydrocarbon wax into the calculation software, and using the value.

<Measurement method of molecular weight of crystalline polyester>
The molecular weight of the crystalline polyester is measured by gel permeation chromatography (GPC) as follows.

First, a crystalline polyester, an amorphous saturated polyester resin or a toner is dissolved in tetrahydrofuran (THF) at room temperature. Then, the obtained solution is filtered through a solvent-resistant membrane filter "Maeshori Disc" (manufactured by Tosoh Corporation) having a pore diameter of 0.2 μm to obtain a sample solution. The sample solution is adjusted so that the concentration of the component soluble in THF is 0.8% by mass. This sample solution is used for measurement under the following conditions.
Equipment: High-speed GPC equipment "HLC-8220GPC" [manufactured by Tosoh Corporation]
Column: LF-604 double eluent: THF
Flow velocity: 0.6 ml / min
Oven temperature: 40 ° C
Sample injection volume: 0.020 ml

In calculating the molecular weight of the sample, standard polystyrene resin (for example, trade name "TSK standard polystyrene F-850, F-450, F-288, F-128, F-80, F-40, F-20, F-" 10, F-4, F-2, F-1, A-5000, A-2500, A-1000, A-500 ", manufactured by Tosoh Corporation) is used.

<Measurement of molecular weight of hydrocarbon wax>
The molecular weight of the hydrocarbon wax can be measured by high temperature gel permeation chromatography (GPC).

As a specific method, 0.03 g of ester wax is added to o-dichlorobenzene for gel chromatograph, and special grade 2,6-di-t-butyl-4-methylphenol (BHT) is added to a concentration of 0.10 wt / vol%. Add so that it becomes, and dissolve at room temperature. Wax and o-dichlorobenzene to which the above BHT is added are placed in a sample bottle and heated on a hot plate set at 150 ° C. to dissolve the wax. When the wax melts, put it in a preheated filter unit and install it in the main body. A GPC sample that has passed through the filter unit is used. The sample solution is adjusted so that the concentration is about 0.15% by mass. This sample solution is used for measurement under the following conditions.

[Analysis conditions]
Equipment: HLC-8121GPC / HT (manufactured by Tosoh Corporation)
Detector: RI for high temperature
Column: TSKgel GMHHR-HHT 2 stations (manufactured by Tosoh)
Temperature: 135.0 ° C
Solvent: o-dichlorobenzene for gel chromatograph (BHT 0.10 wt / vol% added)
Flow velocity: 1.0 ml / min
Injection volume: 0.4 ml
In calculating the molecular weight of the wax, standard polystyrene resin (for example, trade names "TSK standard polystyrene F-850, F-450, F-288, F-128, F-80, F-40, F-20, F-" 10, F-4, F-2, F-1, A-5000, A-2500, A-1000, A-500 ", manufactured by Tosoh Corporation) is used.

<Measurement method of crystallization temperature of hydrocarbon wax and crystalline resin>
The crystallization temperature of the hydrocarbon wax and the crystalline resin was measured using DSC Q1000 (manufactured by TA Instruments) under the following conditions. The measurement conditions were a heating rate of 10 ° C./min, a measurement temperature range of 20 ° C. to 180 ° C., and measurement in standard mode. About 2 mg of the sample was precisely weighed and placed in a silver pan, and an empty silver pan was used as a reference for differential scanning calorimetry. The crystallization temperature of the present invention refers to the peak top temperature of the maximum exothermic peak in the exothermic peak obtained when the temperature is lowered after the temperature is raised to 180 ° C. When there are multiple exothermic peaks, the temperature of the peak with the largest calorific value is adopted. For example, when a plurality of types of hydrocarbon wax are contained, a single substance is obtained, and the hydrocarbon wax is crushed and uniformly mixed at the same ratio as the content in the toner for measurement. The same applies when a plurality of crystalline resins are contained.

Further, when the hydrocarbon wax or the crystalline resin is isolated from the toner and the above measurement is performed, the following methods are available and will be described as an example. First, the toner is dissolved in a highly soluble solvent such as chloroform. At this time, for example, if there is an insoluble component such as a magnetic powder or a gel component, it is removed by a filter paper having a fine opening diameter, a myshori disk, centrifugation or the like. After that, chloroform is removed by volatilizing or the like, and hydrocarbon wax such as tetrahydrofuran and crystalline resin are difficult to dissolve, and a soluble solvent is added to the resin to dissolve most of the resin components. Since the undissolved component is a mixture containing a crystalline resin and a hydrocarbon wax as main components, the crystalline resin and the hydrocarbon wax are separated and isolated by a preparative LC.

Examples are shown below.

The method for producing toner will be described in detail.

<Production example of magnetic iron oxide>
50 liters of ferrous sulfate ferrous aqueous solution containing 2.0 mol / L of Fe ²⁺ is mixed and stirred with 55 liters of 4.0 mol / L sodium hydroxide aqueous solution, and ferrous salt aqueous solution containing ferrous hydroxide colloid is mixed and stirred. Got This aqueous solution was kept at 85 ° C. and an oxidation reaction was carried out while blowing air at 20 L / min to obtain a slurry containing core particles.

The obtained slurry was filtered and washed with a filter press, and then the core particles were redispersed in water and reslurryed. To this reslurry liquid, sodium silicate, which is 0.20% by mass in terms of silicon with respect to the core particles, is added, the pH of the slurry liquid is adjusted to 6.0, and the mixture is stirred to obtain magnetic iron oxide having a silicon-rich surface. Obtained particles. The obtained slurry was filtered and washed with a filter press, and further reslurryed with ion-exchanged water. 500 g (10% by mass with respect to magnetic iron oxide) of an ion exchange resin SK110 (manufactured by Mitsubishi Chemical Corporation) was added to this reslurry solution (solid content 50 g / L), and the mixture was stirred for 2 hours to perform ion exchange. Then, the ion exchange resin was filtered through a mesh to remove it, filtered and washed with a filter press, dried and crushed to obtain magnetic iron oxide having an average number diameter of 0.23 μm.

<Manufacturing of silane compounds>
30 parts by mass of iso-butyltrimethoxysilane was added dropwise to 70 parts by mass of ion-exchanged water with stirring. Then, this aqueous solution was maintained at pH 5.5 and a temperature of 55 ° C., and hydrolyzed by dispersing at a peripheral speed of 0.46 m / s for 120 minutes using a disper blade. Then, the pH of the aqueous solution was adjusted to 7.0, and the solution was cooled to 10 ° C. to stop the hydrolysis reaction. In this way, an aqueous solution containing a silane compound was obtained.

<Manufacturing of magnetic material 1>
100 parts by mass of magnetic iron oxide was placed in a high-speed mixer (LFS-2 type manufactured by Fukae Powtech Co., Ltd.), and 8.0 parts by mass of an aqueous solution containing a silane compound was added dropwise over 2 minutes while stirring at a rotation speed of 2000 rpm. .. Then, it was mixed and stirred for 5 minutes. Then, in order to enhance the stickiness of the silane compound, the mixture was dried at 40 ° C. for 1 hour to reduce the water content, and then the mixture was dried at 110 ° C. for 3 hours to allow the condensation reaction of the silane compound to proceed. Then, it was crushed and passed through a sieve having an opening of 100 μm to obtain a magnetic substance 1.

<Production example of polyester resin>
40 mol% of terephthalic acid, 10 mol% of trimellitic acid, and 50 mol% of bisphenol A-PO2 mol adduct were placed in a reaction vessel equipped with a nitrogen introduction tube, a dehydration tube, a stirrer and a thermocouple, and then dibutyltin was used as a catalyst. 1.5 parts by mass was added with respect to 100 parts by mass of the total amount. Then, after rapidly raising the temperature to 180 ° C. under normal pressure under a nitrogen atmosphere, water was distilled off while heating at a rate of 10 ° C./hour from 180 ° C. to 210 ° C. to carry out polycondensation. After reaching 210 ° C., the pressure inside the reaction vessel was reduced to 5 kPa or less, and polycondensation was carried out under the conditions of 210 ° C. and 5 kPa or less to obtain an amorphous polyester resin. At that time, the polymerization time was adjusted so that the softening point of the obtained polyester resin was 120 ° C.

<Production example of crystalline polyester 1>
After putting 45 mol% of 1,9-nonanediol and 55 mol% of 1,10-dodecanedioic acid in a reaction vessel equipped with a nitrogen introduction tube, a dehydration tube, a stirrer and a thermocouple, tin dioctylate is used as a catalyst as a monomer. 1 part by mass was added to 100 parts by mass of the total amount, and the mixture was heated to 140 ° C. under a nitrogen atmosphere and reacted for 6 hours while distilling off water under normal pressure. Next, the reaction was carried out while raising the temperature to 200 ° C. at 10 ° C./hour, and after reaching 200 ° C., the reaction was carried out for 2 hours. , Crystalline polyester 1 (crystalline resin 1) was obtained. The weight average molecular weight (Mw) of the crystalline polyester 1 was 2000.

<Production example of crystalline polyesters 2 to 13>
In the production example of crystalline polyester 1, crystalline polyesters 2 to 13 (crystalline resins 2 to 13) were obtained by changing the reaction temperature, the monomer ratio, the reaction time, and the amount of catalyst as shown in Table 1.

<Manufacturing example of magnetic toner 1>
Toner particles and toner were manufactured by the following procedure.

(Preparation of first aqueous medium)
2.9 parts by mass of sodium phosphate dodecahydrate was added to 353.8 parts by mass of ion-exchanged water, and T.I. K. Calcium chloride obtained by heating to 60 ° C. with stirring using a homomixer (manufactured by Tokushu Kagaku Kogyo Co., Ltd.), and then adding 1.7 parts by mass of calcium chloride dihydrate to 11.7 parts by mass of ion-exchanged water. An aqueous solution and a magnesium chloride aqueous solution obtained by adding 0.5 parts by mass of magnesium chloride to 15.0 parts by mass of ion-exchanged water were added and stirred to obtain a first aqueous medium.

(Preparation of polymerizable monomer composition)
・ Styrene 70.0 parts by mass ・ n-butyl acrylate 30.0 parts by mass ・ Magnetic material 1 95.0 parts by mass ・ Polyester resin 5.0 parts by mass Atleter (manufactured by Mitsui Miike Kakoki Co., Ltd.) After uniformly dispersing and mixing using the material, the mixture is heated to 60 ° C., and 10.0 parts by mass of hydrocarbon 1 (melting point 76 ° C., crystallization temperature 75 ° C.) shown in Table 2 as a hydrocarbon wax, crystalline resin. As a result, 10.0 parts by mass of crystalline polyester 1 was added and mixed, and dissolved to obtain a polymerizable monomer composition.

(Preparation of second aqueous medium)
0.6 parts by mass of sodium phosphate decahydrate is added to 166.8 parts by mass of ion-exchanged water and heated to 60 ° C. while stirring using a paddle stirring blade, and then 2.3 parts by mass of ion-exchanged water. An aqueous solution of calcium chloride to which 0.3 parts by mass of calcium chloride dihydrate was added was added to the mixture, and stirring was carried out to obtain a second aqueous medium.

(Granulation)
The above-mentioned polymerizable monomer composition is put into the above-mentioned first aqueous medium, and the granulation solution is treated with Cavitron (manufactured by Eurotech) at a peripheral speed of the rotor at 29 m / s for 1 hour. was carried out, uniformly dispersed mixtures, a polymerization initiator as t- butyl peroxypivalate 7.0 part by weight were charged, circumferential at Clearmix (manufactured by M technique Co., Ltd.) at 60 ° C., N ₂ atmosphere Granulation was carried out at a speed of 22 m / s with stirring for 10 minutes to obtain a granulation solution containing droplets of the polymerizable monomer composition.

(Polymerization / Distillation / Drying / Attachment)
The granulation liquid was put into the second aqueous medium and reacted at 74 ° C. for 3 hours while stirring with a paddle stirring blade. After completion of the reaction, the temperature was raised to 98 ° C. and distilled for 3 hours to obtain a reaction slurry. Then, the mixture was cooled from 98 ° C. to 35 ° C. at a rate of 0.5 ° C./min and then allowed to cool to 25 ° C. at room temperature. The allowed-chilled reaction slurry was washed with hydrochloric acid, filtered and dried to obtain toner particles having a weight average particle size of 7.4 μm.

The following materials were mixed with 100 parts by mass of the obtained toner particles with a Mitsui Henschel mixer (FM-10 type manufactured by Mitsui Miike Machinery Co., Ltd.) to obtain a magnetic toner 1.
-Number of primary particles surface-treated with hexamethyldisilazane 0.5 parts by mass of hydrophobic silica fine particles with an average particle size of 5 nm-Strontium titanate of perovskite-type crystals surface-treated with stearic acid
0.3 parts by mass

The physical characteristics of the obtained magnetic toner 1 are shown in Table 4.

<Manufacturing example of magnetic toners 2-19 and 22-29>
In the production example of the magnetic toner 1, magnetic toners 2 to 19 and 22 to 29 were obtained in the same manner as in the production example of the magnetic toner 1 except that the material composition was as shown in Table 3. Table 1 shows the physical characteristics of the obtained magnetic toner.

Hydrocarbon wax was not used for the magnetic toners 26 to 28. As the wax, stearyl stearate was used in the magnetic toners 26 and 27, and tetradecyl stearate was used in the magnetic toner 28. The particle size (D4) of the toner was all in the range of 7.2 to 7.6 μm.

<Manufacturing example of magnetic toner 20>
-Acrylic resin (VS-1057 manufactured by Seiko PMC) 100.0 parts by mass-Iron complex of monoazo dye (T-77: manufactured by Hodogaya Chemical Co., Ltd.) 1.5 parts by mass-Magnetic material 1 95.0 parts by mass-Carbonide Wax 7 5.0 parts by mass, crystalline polyester 8 5.0 parts by mass The above raw materials were premixed with a Mitsui Henchel mixer and then kneaded by a twin-screw kneading extruder set at 130 ° C. and 200 rpm. The obtained kneaded product was rapidly cooled to room temperature, and the cooling rate at this time was 20 ° C./sec or more. After coarse pulverization with a cutter mill, the obtained coarse pulverized product is finely pulverized by adjusting the air temperature so that the exhaust temperature becomes 50 ° C. using a turbo mill T-250 (manufactured by Turbo Industries, Ltd.), and the Coanda effect is obtained. The toner particles 20 were obtained by classifying using a multi-division classifier using the above. Then, the magnetic toner 20 was obtained in the same manner as in the production example of the magnetic toner 1. Table 4 shows the physical characteristics of the toner. The particle size (D4) of the toner was 7.4 μm.

<Manufacturing example of magnetic toner 21>
● Production example of resin particle dispersion ・ 90.0 parts by mass of styrene ・ 10.0 parts by mass of n-butyl acrylate ・ 2.0 parts by mass of β-carboxyethyl acrylate ・ 0.4 parts by mass of 1,6 hexanediol diacrylate ・Dodecanthiol (manufactured by Wako Pure Chemical Industries, Ltd.) 0.7 parts by mass, crystalline polyester 8 3.0 parts by mass The above materials were put into a flask, mixed and dissolved to obtain a solution.

The solution obtained by dissolving 1.0 part by mass of anionic surfactant (Neogen RK, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) in 250 parts by mass of ion-exchanged water was dispersed and emulsified.

While slowly stirring and mixing for 10 minutes, 50 parts by mass of ion-exchanged water in which 2 parts by mass of ammonium persulfate was dissolved was further added.

Next, after sufficiently replacing the inside of the system with nitrogen, the inside of the system was heated to 70 ° C. in an oil bath with stirring, and emulsion polymerization was continued as it was for 5 hours, and the resin particle dispersion liquid (solid content concentration: 25% by mass) was continued. ) Was obtained.

The volume average particle size of the resin particles in the resin particle dispersion was 0.18 μm, the glass transition temperature (Tg) was 56.5 ° C., and the weight average molecular weight (Mw) was 30,000.

● Production example of wax dispersion ・ Hydrocarbon wax 7 50.0 parts by mass ・ Anionic surfactant 0.3 parts by mass (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd., Neogen RK)
-Ion-exchanged water (150.0 parts by mass or more) was mixed, heated to 95 ° C., and dispersed using a homogenizer (Ultratarax T50 manufactured by IKA). Then, it was dispersed with a Menton Gorin high-pressure homogenizer (manufactured by Gorin Co., Ltd.) to prepare a wax dispersion liquid 1 (solid content concentration: 25% by mass) in which wax particles were dispersed. The volume average particle diameter of the obtained wax particles was 0.20 μm.

● Production Example of Magnetic Material for Magnetic Toner 21 55 liters of a 4.0 mol / L sodium hydroxide aqueous solution is mixed and stirred with 50 liters of a first iron sulfate aqueous solution containing 2.0 mol / L of ^{Fe 2+ to obtain hydroxylation.} An aqueous ferrous salt solution containing a ferrous colloid was obtained. This aqueous solution was kept at 85 ° C. and an oxidation reaction was carried out while blowing air at 20 L / min to obtain a slurry containing core particles.

The obtained slurry was filtered and washed with a filter press, and then the core particles were redispersed in water. To the obtained reslurry liquid, sodium silicate, which is 0.20% by mass in terms of silicon with respect to the core particles, is added, the pH of the slurry liquid is adjusted to 6.0, and the mixture is stirred to have a magnetic structure having a silicon-rich surface. Iron oxide particles were obtained.

The obtained slurry liquid was filtered and washed with a filter press, and further reslurryed with ion-exchanged water. 500 parts by mass (10% by mass with respect to magnetic iron oxide) of the ion exchange resin SK110 (manufactured by Mitsubishi Chemical Corporation) is added to this reslurry liquid (solid content 50 parts by mass / L), and the mixture is stirred for 2 hours to perform ion exchange. rice field. Then, the ion exchange resin is filtered with a mesh to remove it, filtered and washed with a filter press, dried and crushed to obtain a magnetic material for magnetic toner 21 having an average number of primary particles of 0.21 μm. rice field.

● Production example of magnetic material dispersion liquid ・ Magnetic material for magnetic toner 21 25.0 parts by mass ・ Ion exchanged water 75.0 city area Mix the above materials and use a homogenizer (Ultra Tarax T50 manufactured by IKA). The mixture was dispersed at 8000 rpm for 10 minutes to obtain a magnetic material dispersion. The volume average particle diameter of the magnetic material in the magnetic material dispersion liquid was 0.23 μm.

● Production example of magnetic toner particles 21 ・ Resin particle dispersion (solid content 25.0% by mass) 150.0 parts by mass ・ wax dispersion (solid content 25.0% by mass) 15.0 parts by mass ・ magnetic material dispersion (Solid content 25.0% by mass) 105.0 parts by mass The above materials were put into a beaker, adjusted so that the total number of parts of water was 250 parts by mass, and then the temperature was adjusted to 30.0 ° C. Then, using a homogenizer (Ultratarax T50 manufactured by IKA), mixing was performed by stirring at 5000 rpm for 1 minute.

Further, 10.0 parts by mass of a 2.0% by mass aqueous solution of magnesium sulfate was gradually added as a flocculant.

The raw material dispersion was transferred to a polymerization vessel equipped with a stirrer and a thermometer, heated to 50.0 ° C. with a mantle heater, and stirred to promote the growth of agglomerated particles.

After 60 minutes had passed, 200.0 parts by mass of a 5.0% by mass aqueous solution of ethylenediaminetetraacetic acid (EDTA) was added to prepare an aggregated particle dispersion.

Subsequently, the agglomerated particle dispersion was adjusted to pH 8.0 with a 0.1 mol / L sodium hydroxide aqueous solution, and then the agglomerated particle dispersion was heated to 80.0 ° C. and left for 180 minutes to leave the agglomerated particles. We united.

After 180 minutes, a toner particle dispersion liquid in which toner particles were dispersed was obtained. After cooling at a temperature lowering rate of 1.0 ° C./min, the toner particle dispersion is filtered, washed with ion-exchanged water, and when the conductivity of the filtrate becomes 50 mS or less, the toner becomes a cake. The particles were taken out.

Next, the cake-shaped toner particles are put into ion-exchanged water having an amount of 20 times the mass of the toner particles, stirred by a three-one motor, filtered again when the toner particles are sufficiently loosened, washed with water, and solidified. The liquid was separated. The obtained cake-shaped toner particles were crushed with a sample mill and dried in an oven at 40 ° C. for 24 hours. Further, the obtained powder was crushed by a sample mill and then subjected to additional vacuum drying in an oven at 40 ° C. for 5 hours to obtain magnetic toner particles 21. Then, the magnetic toner 21 was obtained in the same manner as in the production example of the magnetic toner 1. Table 4 shows the physical characteristics of the toner. The particle size (D4) of the toner was 7.4 μm.

Next, Examples and Comparative Examples will be described in detail.

[Example 1]
A commercially available laser printer LaserJetEnterprise M506 (manufactured by Hewlett-Packard Co., Ltd.) was used for the image drawing evaluation of the examples. The cartridge was taken out from the main body, the product toner was taken out from the cartridge, and 300 g of magnetic toner 1 was filled. The main body and the cartridge were left for 24 hours in their respective environments in which the temperature and humidity were controlled, and then the image was evaluated. Regarding the image output evaluation, the following evaluation was performed and the judgment was made using the following indicators. The evaluation results are shown in Table 5.

As an output image for the developability evaluation test in a low-temperature and low-humidity environment (15.0 ° C./10.0% RH), 1000 horizontal line images with a printing rate of 1% were printed on two intermittent sheets. .. The evaluation paper used for the test was ^{a businesss 4200 (manufactured by Xerox) having a basis weight of 75 g / m 2} , and the difference in image density before and after printing 1000 sheets was measured with a Macbeth reflection densitometer (manufactured by Macbeth). .. The low-temperature and low-humidity environment is an environment in which changes in the charge distribution can be strictly observed. For example, when the dispersed state of the crystalline resin or hydrocarbon wax changes, the image density tends to decrease.

The criteria for determining the difference in reflection density of solid black images before and after durable use are as follows.
[Evaluation criteria]
A: 0.02 or less B: 0.03 or more and less than 0.06 C: 0.06 or more and less than 0.15 D: 0.15 or more

Evaluation of gloss unevenness Using the above printer, five solid black images were output continuously. Each solid black image was divided into 9 parts, and the gloss value was measured using PG-3D (manufactured by Nippon Denshoku Kogyo Co., Ltd.). Data of 9 points was taken for all 5 sheets, and the maximum value, the minimum value, and the average value of 45 points were calculated. It was evaluated by the fluctuation range with respect to the average value of the maximum value and the minimum value.
[Evaluation criteria]
A: 3.0% or less B: 3.1% or more and 5.0% or less C: 5.1% or more and 10.0% or less D: 10.1% or more

<Evaluation of storage stability>
It was left in an environment of a temperature of 45 ° C. and a humidity of 50% for 20 days, and then 500 solid white images were printed continuously to output a solid black image. Therefore, the storage stability was evaluated based on whether vertical white streaks (development streaks) appeared. A visual judgment was made, and if there was no problem, another 500 sheets were printed and evaluated in the same manner, and up to 5000 sheets were evaluated. If the storage stability is poor, toner agglomerates and tends to appear as vertical white streaks in the image.
[Evaluation criteria]
A: No occurrence even at 5000 sheets B: Occurs at 5000 sheets larger than 4000 sheets C: Occurs at 4000 sheets or less larger than 2000 sheets D: Occurs at 2000 sheets or less

[Examples 2 to 21, Comparative Examples 1 to 8]
The magnetic toners 2 to 29 were evaluated in the same manner as in Example 1. The evaluation results are shown in Table 5.

Claims (10)

A toner containing toner particles having a binder resin, a crystalline resin, a hydrocarbon wax, and a colorant.
The crystalline resin has a weight average molecular weight of 1000 or more and 4500 or less.
A toner characterized in that the difference in solubility parameter between the crystalline resin and Hansen of the hydrocarbon wax is 2.5 or less. The toner according to claim 1, wherein the difference in crystallization temperature between the hydrocarbon wax and the crystalline resin is 2 ° C. or more. The toner according to claim 1 or 2, wherein the crystalline resin is a crystalline polyester. The toner according to any one of claims 1 to 3, wherein the crystalline polyester is a condensate of an aliphatic dicarboxylic acid and an aliphatic diol. The toner according to any one of claims 1 to 4, wherein the hydrocarbon wax has a weight average molecular weight of 300 or more and 2000 or less. The crystalline polyester is mainly composed of a component composed of an aliphatic diol and an aliphatic dicarboxylic acid, the aliphatic diol has 7 or more carbon atoms, and the aliphatic dicarboxylic acid has 12 or more carbon atoms. The toner according to any one of claims 1 to 5. The toner according to any one of claims 1 to 6, wherein the hydrocarbon wax and the crystalline resin form a composite crystal inside the toner. The toner according to any one of claims 1 to 7, wherein the colorant is a magnetic material. Claim 4 or the structure in which the aliphatic dicarboxylic acid has a carboxyl group at both ends of a linear alkylene group, and the aliphatic diol has a hydroxyl group at both ends of a linear alkylene group. 6. The toner according to 6. The method for producing a toner according to any one of claims 1 to 9, further comprising a step of mixing a hydrocarbon wax and a crystalline resin in a molten state.