JPH0943896A - Toner for developing electrostatic image and method for producing the same - Google Patents

Abstract

(57) Abstract: An object of the present invention is an electrostatic charge having excellent durability and frictional electrification of many sheets, little fog and toner scattering, and improved stability of electrification when enduring many sheets. An object is to provide an image developing toner and a method for manufacturing the same. The present invention provides a toner for developing an electrostatic charge image, which comprises toner particles containing at least a binder resin and a colorant, wherein the toner particles contain at least an internal low softening point substance, An inner layer covering the inside, and an upper layer covering the inside and the inner layer, wherein the inside, the inner layer and the upper layer are distinguished by a ruthenium tetraoxide and an osmium tetraoxide staining method. The present invention relates to a toner for developing an electrostatic charge image, which is composed of the obtained material.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toner for developing an electrostatic charge image, which is used for developing an electrostatic charge image and is suitable for heat and pressure fixing, and a method for producing the toner.

[0002]

2. Description of the Related Art Conventionally, as an electrophotographic method, US Pat.
Many methods are known, as described in Japanese Patent Publication No. 297,691, Japanese Patent Publication No. 42-23910, and Japanese Patent Publication No. 43-24748. Generally, a photoconductive substance is used to form an electrostatic charge image on a photoconductor by various means, and then the electrostatic charge image is developed with toner to form a toner image, and if necessary, a paper sheet is formed. After the toner image is transferred onto the transfer material as described above, it is fixed by heating, pressure, heating pressure, solvent vapor or the like to obtain a copy image or a print image.

As a method of developing with toner or a method of fixing a toner image, various methods have been conventionally proposed, and methods suitable for respective image forming processes are adopted. Conventionally, toners used for these purposes are generally toners having a desired particle diameter by a fine pulverizer and a classifier after a coloring material composed of a dye and / or a pigment is melt-mixed in a thermoplastic resin and uniformly dispersed. Has been manufactured.

While these manufacturing methods can produce fairly good toners, they have certain limitations. For example, the colorant-dispersed resin composition must be sufficiently brittle to be finely pulverized in an economically feasible manufacturing apparatus. However,
When the colorant-dispersed resin composition is made brittle, the particle size range of the particles formed when the particles are actually finely pulverized at a high speed tends to be wide, and in particular, there is a problem that relatively large particles are contained therein.

Further, such a brittle material is susceptible to further fine pulverization or pulverization when used for development. With this method, it is difficult to uniformly and satisfactorily disperse solid fine particles such as a colorant in the resin. Depending on the degree of dispersion, fog increases, image density decreases, toner color mixing, or transparency. Cause the decrease of. The exposure of the colorant on the fracture surface of the toner particles may cause fluctuations in the developing characteristics of the toner.

On the other hand, in order to overcome the problems of the toner produced by the pulverization method, Japanese Patent Publication Nos. 36-10231, 42-10799, and 51.
For example, JP-A-14895 discloses a method for producing a toner by a suspension polymerization method. In the suspension polymerization method, a polymerizable monomer, a colorant, a polymerization initiator, and optionally a crosslinking agent, a charge control agent, and other additives are uniformly dissolved or dispersed to obtain a monomer composition. After that, this monomer composition is dispersed in an aqueous medium containing a dispersion stabilizer using a suitable stirrer, and the polymerizable monomer is polymerized to obtain toner particles having a desired particle size.

Since this method does not include a crushing step, the toner particles need not be brittle and a soft material can be used, and the colorant is not exposed on the surface of the toner particles. , Having uniform triboelectric chargeability. Since the classification step can be omitted, there are great cost reduction effects such as energy saving, shortening of manufacturing time, and improvement of process yield.

However, even with such a manufacturing method, when the toner particles are made into fine particles, the colorant is likely to be exposed on the surface layer of the toner particles, and the effect of the colorant is likely to occur. And the development characteristics are likely to change.

Then, the phenomenon becomes particularly noticeable when copying or printing is continued under high humidity. Conventionally, in order to make charging uniform, for example, JP-A-62-73277 and JP-A-3-35660 propose methods of coating the surface layer of toner particles with a resin.

However, in these methods, since the coating layer is thick, the influence of the coloring agent can be surely prevented, but the component having the charge controllability can hardly be contained. However, there was a problem that the absolute value of the charge amount of the toner becomes small.

For this reason, a method of coating the surface of the toner particles in multiple stages has been proposed in JP-A-64-62666, JP-A-64-63035, and JP-B-58-57105. In addition, the manufacturing process is complicated.
It is a cost disadvantage. In order to improve such problems, a method of depositing a charge control agent on the surface of toner particles is
JP-A-61-273558, JP-A-5-1344
No. 37, etc. However, in this method, in consideration of the durability of the toner that occurs when copying or printing is repeated, the charge control agent is detached from the toner surface, which causes a problem in durability characteristics.

In recent years, digital full-color copying machines and printers have been put on the market, and it has become possible to obtain high image quality not only in resolution and gradation but also in color reproducibility without color unevenness.

In a digital full-color copying machine or full-color printer, color image originals are B (blue), G
After color separation with each of the (green) and R (red) filters, an electrostatic charge image having a dot diameter of 20 to 70 μm corresponding to the original image is displayed as Y (yellow), M (magenta), C (cyan) and Development is performed by utilizing the subtractive color mixing action using each color Bk (black) toner agent. Compared with a black-and-white copying machine, it is necessary to transfer a large amount of toner from a photoconductor to a transfer material, and it is required to reduce the toner particle size corresponding to minute dots in order to achieve high image quality.

With the speeding up and full-colorization of printers and copying machines in the future, further improvement in low-temperature fixability will become an important factor. From this point as well, toner particles having a sharp particle size distribution and fine particle size can be relatively easily obtained. Polymerization toners capable of producing are preferred. Toners installed in full-color copiers or full-color printers require that color toners be sufficiently mixed in the fixing process, which improves color reproducibility and transparency of overhead projector (hereinafter referred to as OHP) images. is important. Further, the color toner is preferably a low molecular weight resin which has better melting property than the black toner.

As a releasing agent for the black toner, a wax having a relatively high crystallinity represented by polyethylene wax or polypropylene wax is used for the purpose of improving the high temperature offset resistance during fixing. However, in the color toner for full color, the transparency of the image is deteriorated when output to the OHP because the crystallinity of the wax is high.

Therefore, as an ordinary color toner component, an anti-offset liquid such as silicone oil is applied to a heat fixing roller without adding a release agent to improve high temperature offset resistance. There is.

For this reason, the transfer material after fixing is not preferable because extra silicone oil adheres to the surface of the transfer material, which may cause discomfort when the user handles it.

Therefore, a toner for oilless fixing in which a large amount of a substance having a low softening point is contained in the toner particles has been studied, but it is further excellent in low-temperature fixing property and transparency and, at the same time, is resistant to high temperature offset. There is a long-awaited need for toners that exhibit properties.

As a method for solving such various problems, Japanese Patent Application Laid-Open No. 1-230073 discloses a color image fixing method using a polymerization toner containing a low-softening substance having releasability. . Deterioration of toner development characteristics during the durability test, which is considered to be caused by the low softening point substance leaching onto the surface of the toner particles, tends to occur.

A polar polymer or polar copolymer may be added to the polymerizable monomer composition for the purpose of preventing the exposure of the colorant to the surface of the toner particles and the exudation of the low softening point substance. , JP-A-61-35457, and further,
JP-A-6-317925 discloses that a hydrophilic outer shell material is provided on the surface of toner particles.

However, even if this method is used, since the material forming the outer shell is hydrophilic, the developing property under high humidity is poor and the durability is poor. Furthermore, in order to improve the inhibition of fixing by the outer shell material, the glass transition point of the resin of the core material is 10 to 50 ° C.
Since it is set to, the transfer material is easily wrapped around the fixing roller during fixing.

Therefore, the toner produced by the polymerization method,
Particularly for color toners, there is a demand for toners that can satisfactorily solve the problems caused by both the developing characteristics and the fixing characteristics.

[0023]

SUMMARY OF THE INVENTION An object of the present invention is to provide a toner for developing an electrostatic charge image, which solves the above problems of the prior art.

An object of the present invention is to provide a toner for developing an electrostatic charge image in which the functional separation of the inside, inner layer portion and outer layer portion of toner particles is improved.

An object of the present invention is to provide a toner for developing an electrostatic charge image which is excellent in triboelectric chargeability and has stable triboelectric chargeability in each environment.

An object of the present invention is to provide a toner for developing an electrostatic charge image capable of forming a high quality toner image with high image density and less fog.

An object of the present invention is to provide a toner for electrostatic charge image development in which toner scattering is less likely to occur in an image forming apparatus.

An object of the present invention is to provide an electrostatic charge image developing toner excellent in durability of a large number of sheets.

An object of the present invention is to provide a toner for developing an electrostatic charge image, which is formed of color toner particles having excellent color mixing properties and good translucency.

An object of the present invention is to provide a manufacturing method for producing the above toner.

[0031]

The present invention provides a toner for developing an electrostatic charge image, which comprises toner particles containing at least a binder resin and a colorant, the toner particles having at least an internal portion. A softening point substance, an inner layer covering the inside, and an upper layer covering the inside and the inner layer, wherein the inside, the inner layer and the upper layer are ruthenium tetraoxide and osmium trioxide. The present invention relates to a toner for developing an electrostatic charge image, which is composed of a material that can be identified by a dyeing method.

Further, in the present invention, a polymerizable monomer composition containing at least a polymerizable monomer, a colorant, a substance having a low softening point, a resin having a polar group and a polymerization initiator is prepared, and a polymerizable monomer composition is prepared. The monomer composition is dispersed in an aqueous medium to produce particles of the polymerizable monomer composition, and the polymerizable monomer in the particles is polymerized to produce toner particles. The aqueous medium is heated to a temperature 5 ° C. or more higher than the peak temperature and 5 ° C. or more higher than the glass transition temperature of the resin having a polar group, and then the aqueous medium is heated to 50 ° C. at a cooling rate of 2 ° C. or less per minute.
A method for producing a toner in which the toner particles are cooled to a temperature of not higher than 0 ° C. and the toner particles are filtered from an aqueous medium to produce toner particles, wherein the toner particles at least cover the low softening point substance forming the inside and the inside. The inner layer and the upper layer covering the inner layer and the inner layer, and the inner layer, the inner layer and the upper layer are composed of ruthenium trioxide and a material identifiable by an osmium trioxide trioxide staining method. And a method for producing a toner.

[0033]

According to the present invention, the durability is improved, and the fine irregularity of the chargeability of the toner particle surface is thickly coated with a polymer as in the prior art, or the charge control agent is used as a toner. Rather than preventing it from adhering to the surface of the particles, the inside of the low softening point substance is first covered with an inner layer, and the inner layer is further covered with an upper layer. The toner particles are embedded with an epoxy resin or the like, and further, the cross section is stained with ruthenium tetraoxide and osmium trioxide, and when the section is subsequently observed using a transmission electron microscope, the inner and inner layers, And the materials capable of forming the upper layer are composed of materials that are identified as different from each other, the functional separation of each part is improved, and the colorant, the charge control agent, and the low softening point substance are encapsulated in the toner particles. As a result, excellent developing characteristics and fixing characteristics are exhibited.

The present invention will be described in detail below with reference to preferred embodiments.

The thickness of the upper layer of the toner particles of the present invention is measured by a transmission electron microscope according to the following measuring method.
When it can be confirmed as a layer having a thickness of 01 to 0.5 μm, the effect of the present invention can be exerted in proper proportion, which is preferable. When the thickness of the upper layer is less than 0.01 μm, the colorant and the low softening point compound cannot be sufficiently covered, and when it exceeds 0.5 μm, the fixability tends to be lowered. A more preferable thickness is 0.05 to 0.4 μm.

In the present invention, as a specific method for measuring the cross-sectional morphology of toner particles, the toner particles are sufficiently dispersed in a room temperature curable epoxy resin, and then the toner particles are left to cure at 40 ° C. for 2 days. The obtained cured product is cut out into a flaky sample using a microtome equipped with diamond teeth, and ruthenium tetraoxide and osmium trioxide are used in combination, and dyeing is caused due to a slight difference in crystallinity,
The difference is confirmed using a transmission electron microscope (TEM). A schematic diagram of a typical example thereof is shown in FIG.

The toner particles of the present invention are preferably toner particles produced by a polymerization method such as a suspension polymerization method, an emulsion polymerization method, an interfacial polymerization method, a dispersion polymerization method and an association polymerization method, which are manufactured in an aqueous medium. In particular, it is necessary to form the upper layer with a material that can be identified by staining with ruthenium tetroxide and osmium tetroxide from the interior or center or from the inner layer.

As such a material for the upper layer, a resin having a polar group, having a glass transition point of 55 to 80 ° C., an acid value of 1 to 35, and more preferably 5 to 35 is suitable. The resin having a polar group is dissolved in a polymerizable monomer composition, and then, in the step of granulating the polymerizable monomer composition into droplets having a toner particle size in an aqueous medium, the toner particles and The resulting droplet particles gather near the surface, and the upper layer of the toner particles is preferably formed by the subsequent polymerization step and slow cooling step.

Therefore, when the transition point of the resin glass having a polar group is less than 55 ° C., the strength of the upper layer of the toner is lowered and the transferability and durability are deteriorated. On the other hand, when the temperature exceeds 80 ° C., the strength of the upper layer becomes too high, and the effect of the charge control agent inside the toner particles tends to be prevented from reaching the surface of the toner particles, and the charge stability of the toner decreases, and the developing characteristics Fluctuates easily. Furthermore, the acid value of the resin having a polar group is 1
If the amount is less than the above, the strength of the upper layer formed is lowered, the transferability and the durability are lowered, and if the acid value exceeds 35, a colorant or a low softening point compound is likely to be deposited on the surface of the toner particles, which is not preferable.

The glass transition point of the resin is measured by ASTMD.
3418-8, Perkin Elmer DSC
-7 is used. The melting point of indium and zinc is used for the correction of the device detection unit, and the heat of fusion of indium is used for the correction of the amount of heat. An aluminum pan was used as a sample, and an empty pan was set as a control, and the heating rate was 10 ° C / m.
in. To measure. The acid value of resin is measured by JIS-K-
It is performed according to 0070.

The addition amount of the resin having a polar group is preferably 1 to 100 parts by weight of the binder resin in the toner particles.
20 parts by weight, more preferably 2.5 to 15 parts by weight. When the amount is less than 1 part by weight, the function as the upper layer of the toner particles is deteriorated, and when the amount is more than 20 parts by weight, the upper layer formed on the toner particles is excessive and the charge stability of the toner is likely to be deteriorated.

Among the resins having a polar group, polyester resin or its derivative is preferable. The composition of a typical polyester resin is as follows.

As the alcohol component of the polyester resin, ethylene glycol, propylene glycol, butanediol, diethylene glycol, triethylene glycol, pentanediol, hexanediol, neohentyl glycol, hydrogenated bisphenol A, or the following formula (I) is used. Examples thereof include bisphenol derivatives represented, and diols represented by the following formula (II).

[0044]

[Outside 1] (In the formula, R is an ethylene or propylene group, x and y are each an integer of 1 or more, and the average value of x + y is 2 to 10.)

[0045]

[Outside 2]

Examples of the divalent carboxylic acid containing 50 mol% or more in all the acid components include benzenedicarboxylic acids such as phthalic acid, terephthalic acid, isophthalic acid and phthalic anhydride or their anhydrides; succinic acid, adipic acid and sebacic acid. , Alkyl dicarboxylic acids such as azelaic acid, and anhydrides thereof. Examples thereof include polyhydric alcohols such as glycerin, pentaerythritol, sorbit, sorbitan, and oxyalkylene ethers of novolak type phenolic resins; and polycarboxylic acids such as trimellitic acid, pyromellitic acid, benzophenonetetracarboxylic acid and their anhydrides.

The particularly preferred alcohol component of the polyester resin is the bisphenol derivative represented by the above formula (I), and the acid component is phthalic acid, terephthalic acid, isophthalic acid, trimellitic acid or their anhydrides. To be

The polymerizable monomer that can be used to form the toner particles of the present invention includes vinyl-based polymerizable monomers. For example, styrene; α-methylstyrene, β-methylstyrene, o-methylstyrene, m
-Methylstyrene, p-methylstyrene, 2,4-dimethylstyrene, pn-butylstyrene, p-tert
-Butylstyrene, pn-hexylstyrene, pn
Styrene derivatives such as -octyl, pn-nonylstyrene, pn-decylstyrene, pn-dodecylstyrene, p-methoxystyrene, p-phenylstyrene;
Methyl acrylate, ethyl acrylate, n-propyl acrylate, iso-propyl acrylate, n-
Butyl acrylate, iso-butyl acrylate, t
ert-butyl acrylate, n-amyl acrylate, n-hexyl acrylate, 2-ethylhexyl acrylate, n-octyl acrylate, n-nonyl acrylate, cyclohexyl acrylate, benzyl acrylate, dimethyl phosphate ethyl acrylate, diethyl phosphate ethyl acrylate, dibutyl phosphate. Acrylic polymerizable monomers such as fate ethyl acrylate and 2-benzoyloxyethyl acrylate; methyl methacrylate, ethyl methacrylate,
n-propyl methacrylate, iso-propyl methacrylate, n-butyl methacrylate, iso-butyl methacrylate, tert-butyl methacrylate, n
-Methacrylic polymerizable monomers such as amyl methacrylate, n-hexyl methacrylate, 2-ethylhexyl methacrylate, n-octyl methacrylate, n-nonyl methacrylate, diethyl phosphate ethyl methacrylate, dibutyl phosphate ethyl methacrylate; methylene aliphatic monocarboxylic Acid esters;
Vinyl acetate, vinyl propionate, vinyl benzoate,
Vinyl esters such as vinyl butyrate, vinyl benzoate, vinyl formate; vinyl ethers such as vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether;
Vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone and vinyl isopropyl ketone can be mentioned.

The inner layer is composed of a vinyl polymer formed from these vinyl polymerizable monomers. Among these vinyl-based polymerizable monomers, a styrene polymer or a styrene-acrylic copolymer or a styrene-methacrylic copolymer is used in order to effectively cover the low softening point substance forming the inside or the central portion. preferable.

Among these polymers, a polymer or a copolymer having a glass transition point of more than 50 ° C. and less than 100 ° C. is particularly preferable. When the glass transition point is below 50 °,
At the time of fixing, the adhesive force to a fixing unit such as a fixing roller becomes high, the transfer material carrying the toner image becomes difficult to peel from the fixing unit, and the problem of winding around the fixing roller easily occurs. Further, the strength of the entire toner particles is lowered, and the transferability and the developing characteristics are likely to be lowered in the multiple durability test. If the obtained fixed images are placed on top of each other for a long period of time, the images may stick together due to the low glass transition point. On the other hand, when the glass transition point is 100 ° C. or higher, the problem of poor fixing tends to occur.

Those polymers or copolymers having a main peak in the molecular weight range of 10,000 to 50,000 in gel permeation chromatograph (GPC) have a large amount of low softening in the center. It is excellent for encapsulating point substances. When the main peak of the molecular weight of the polymer or copolymer constituting the inner layer is less than 10,000, the interaction between the molecular chains of the polymer or copolymer becomes weak, and the low softening point constituting the inside or the central part The substance cannot be sufficiently covered, and the low softening point substance is liable to cause deterioration in developing characteristics. On the other hand, when the main peak of the polymer or copolymer exceeds 50,000, the interaction between the molecular chains of the polymer or copolymer becomes too strong, and the low softening point substance at the time of heat and pressure fixing of the toner Is insufficiently leached to the surface of the toner particles, and if the fixing temperature is relatively low, defective fixing and low temperature offset phenomenon are likely to occur.

Further, the molecular weight is 15,000 to 40,000.
When a styrene polymer or styrene copolymer having a main peak is used, the toner particles have sufficient strength and exhibit excellent triboelectrification characteristics, so that very excellent development characteristics are exhibited. Due to the sufficient strength of the toner particles, deterioration of the toner is less likely to occur even after the durability test, and stable transferability and development characteristics can be maintained.

The molecular weight of the polymer or copolymer is measured by gel permeation chromatography (GPC). As a specific method for measuring GPC, the toner is previously extracted with toluene using a Soxhlet extractor for 20 hours, and then the toluene is distilled off with a rotary evaporator to obtain an extract. Further, if necessary, a polymer or a copolymer is used. Was thoroughly washed with an insoluble organic solvent (for example, chloroform), and the solution of the residue in tetrahydrofuran (THF) was filtered through a membrane filter with a solvent resistance of 0.3 μm in pore size. The sample
150C manufactured by Waters Co. is used, and the column configuration is A-801, 802, 803, 804, 805 manufactured by Showa Denko,
806 and 807 are connected and the molecular weight distribution is measured using a standard polystyrene resin calibration curve.

As the low softening point substance as a material constituting the inside or the central part of the present invention, the endothermic main in the DSC endothermic curve measured in accordance with ASTM D3418-8 is the same as the measurement of the glass transition point. The peak value is 55
To 120 ° C., more preferably a compound showing a value of 60 to 90 ° C., especially a tangential desorption temperature of a DSC curve of 4
A compound having a low softening point of 0 ° C. or higher is more preferable. When the endothermic main peak is less than 55 ° C., the self-cohesive force of the low softening point substance is weak, so that it is difficult to form the inside or the central portion of the toner particles. Precipitates and easily adversely affects development characteristics. Further, if the tangential line detachment temperature is lower than 40 ° C., the strength of the toner particles is lowered, and the developing characteristics during the durability test are apt to be lowered. The resulting fixed image also tends to be a sticky image due to the low melting point of the low softening point substance.

On the other hand, if the endothermic main peak exceeds 120 ° C., the low softening point substance is less likely to ooze out at the time of fixing and the low temperature fixability will be deteriorated. Furthermore, when the toner particles are produced by the direct polymerization method, the solubility in the polymerizable monomer composition is lowered, and the polymerizable monomer composition in the aqueous medium has a particle size of the toner particle size. A low softening point substance is precipitated during the granulation of the droplets, which makes the granulation difficult, which is not preferable. More preferably, 6
It is in the range of 0-90, most preferably 60-85C.
A schematic diagram of the DSC endothermic curve of the low softening point substance is shown in FIG.
Furthermore, the low softening point substance has a half-value width of the endothermic main peak of 1
A material having a sharp melt property within 0 ° C., more preferably within 5 ° C. is preferable.

As the low softening point substance, solid wax which is solid at room temperature is preferable. Specifically, paraffin wax,
Examples thereof include polyolefin wax, Fischer-Tropish wax, amide wax, higher fatty acid, ester wax, and derivatives such as graft compounds and block compounds. An ester wax having one or more long-chain ester moieties having 10 or more carbon atoms represented by the following general structural formula is particularly preferable because it has an effect on high-temperature offset resistance without impairing the transparency of OHP. The structural formulas of typical compounds of the specific ester waxes preferred for the present invention are shown below as general structural formulas (1) to (4).

[0057]

[Outside 3] (In the formula, a and b represent an integer of 0 to 4, a + b is 4, R ₁ and R ₂ represent an organic group having a carbon number of 1 to 40, and the carbon number of R ₁ and R ₂ A group having a difference of 10 or more is shown, n and m are integers of 0 to 15, and n and m are not 0 at the same time.

[0058]

[Outside 4] (In the formula, a and b represent an integer of 0 to 4, a + b is 4, R ₁ represents an organic group having 1 to 40 carbon atoms, and n and m
Represents an integer of 0 to 15, and n and m are never 0 at the same time. )

[0059]

[Outside 5] (In the formula, a and b represent an integer of 0 to 3, a + b is 3 or less, R ₁ and R ₂ represent an organic group having 1 to 40 carbon atoms, and R ₁ and R ₂ are carbon atoms. R ₃ represents a group having a difference of 10 or more, R ₃ represents an organic group having 1 or more carbon atoms, n and m represent integers of 0 to 15, and n and m are not 0 at the same time.) General structural formula of ester wax R ₁ COOR ₂ (wherein R ₁ and R ₂ represent a hydrocarbon group having 1 to 40 carbon atoms, and R ₁ and R ₂ may be the same or different from each other. General formula of ester wax R ₁ COO (CH ₂ ) _n OOCR ₂ (wherein R ₁ and R ₂ represent a hydrocarbon group having 1 to 40 carbon atoms, and n is an integer of 2 to 20). , And R ₁ and R ₂
May have the same or different carbon numbers. ) General structure formula of ester wax R ₁ OOC (CH ₂ ) _n COOR ₂ (In the formula, R ₁ and R ₂ represent a hydrocarbon group having 1 to 40 carbon atoms, and n is an integer of 2 to 20, And R ₁ and R ₂
May have the same or different carbon numbers. )

The ester wax preferably used in the present invention has a melt viscosity measured at 100 ° C. of 1 to 50 mPas.
Xsec is preferable. The melt viscosity of the ester wax is, for example, Visco Tester VT5 manufactured by HAAKE.
00 is used for measurement. If the melt viscosity is less than 1 mPa × sec, the effect of preventing high temperature offset decreases, and
If it exceeds 50 mPa · s, the wax is unlikely to seep out at the time of fixing and the low temperature fixability is deteriorated.

The low softening point substance preferably has a weight average molecular weight (Mw) of 300 to 1,500. If it is less than 300, the low softening point substance is likely to be exposed on the surface of the toner particles, and if it exceeds 1,500, the low temperature fixing property is deteriorated. The range of 400 to 1,250 is particularly preferable. Furthermore, the ratio of the weight average molecular weight / number average molecular weight (M
When w / Mn) is 1.5 or less, DS of low softening point substance
The maximum peak of the C endothermic curve becomes sharper, the mechanical strength of the toner particles at room temperature is improved, and particularly excellent toner characteristics exhibiting sharp melting characteristics at the time of fixing are obtained.

The molecular weight of the low softening point substance is measured by GPC under the following conditions.

(GPC measurement conditions) Apparatus: GPC-150C (Waters) Column: GMH-HT 30 cm 2 stations (manufactured by Tosoh Corporation) Temperature: 135 ° C. Solvent: o-dichlorobenzene (0.1% ionol added) Flow rate: 1. 0 ml / min sample: 0.4 ml of 0.15% sample injected

The molecular weight calibration curve prepared by the monodisperse polystyrene standard sample is used for the measurement of the molecular weight of the sample measured under the above conditions. In addition, Mark-Houw
It is calculated by converting into polyethylene using a conversion formula derived from the ink viscosity formula.

The following compounds may be mentioned as specific examples of the low softening point substance.

(1) CH ₃ (CH ₂ ) ₂₀ COO (CH ₂ ) ₂₁ CH ₃ (2) CH ₃ (CH ₂ ) ₁₇ COO (CH ₂ ) ₉ OOC
(CH ₂ ) ₁₇ CH ₃ (3) CH ₃ (CH ₂ ) ₁₇ OOC (CH ₂ ) ₁₈ COO (CH ₂
) ₁₇ CH ₃

In recent years, the need for full-color double-sided images has been increasing, and in forming a double-sided image, the toner image on the transfer material formed first on the front surface and the image formed on the rear surface next time are formed. May pass through the heating portion of the fixing device again, and it is necessary to sufficiently consider the high temperature offset resistance of the fixed image of the toner at that time. Therefore, in the present invention, it is preferable to include a large amount of the low softening point substance in the toner particles. Specifically, the low softening point substance is preferably added to the toner particles in an amount of 5 to 30% by weight.
If it is added in an amount of less than 5% by weight, the high temperature offset resistance decreases,
Further, the image on the back side may show an offset phenomenon when the double-sided image is fixed. If it is more than 30% by weight, coalescence of toner particles is likely to occur during granulation in the production by the polymerization method, and particles having a wide particle size distribution are likely to be produced.

In the present invention, it is preferable to add a charge control agent to the toner particles for the purpose of controlling the chargeability of the toner.

Of these known charge control agents, those having almost no polymerization inhibitory property or water phase transfer property are preferable. For example, a nigrosine dye as a positive charge control agent,
Examples thereof include triphenylmethane dyes, quaternary ammonium salts, guanidine derivatives, imidazole derivatives and amine compounds. Examples of the negative charge control agent include metal-containing salicylic acid copolymers, metal-containing monoazo dye compounds, urea derivatives, styrene-acrylic acid copolymers, and styrene-methacrylic acid copolymers.

The amount of these charge control agents added is preferably 0.1 to 10% by weight of the binder resin or polymer monomer.

As the polymerization initiator used when the toner particles are produced by the polymerization method, 2,2'-azobis- (2,4-
Divaleronitrile), 2,2'-azobisisobutyronitrile, 1,1'-azobis (cyclohexane-1-carbonitrile), 2,2'-azobis-4-methoxy-
Azo-based or diazo-based polymerization initiators such as 2,4-dimethylvaleronitrile and azobisisobutyronitrile; benzoyl peroxide, methyl ethyl ketone peroxide, diisopropyloxy carbonate, cumene hydroperoxide, 2,4-dichlorobenzoyl peroxide, lauroyl peroxide And a peroxide-based polymerization initiator such as These polymerization initiators are preferably added in an amount of 0.5 to 20% by weight of the polymerizable monomer, and may be used alone or in combination.

A crosslinking agent or a chain transfer agent may be added to control the molecular weight of the binder resin of the toner particles.
The preferable addition amount is 0.001 to 1 of the polymerizable monomer.
15% by weight.

The aqueous dispersion medium may contain, as a dispersion stabilizer for the particles of the polymerizable monomer composition, for example, tricalcium phosphate, magnesium phosphate, zinc phosphate, aluminum phosphate, calcium carbonate, magnesium carbonate, water. Examples thereof include fine powders of inorganic compounds such as calcium oxide, magnesium hydroxide, aluminum hydroxide, calcium metasilicate, calcium sulfate, barium sulfate, bentonite, silica and alumina.

Examples of the dispersion stabilizer include polyvinyl alcohol, gelatin, methyl cellulose, methyl hydroxypropyl cellulose, ethyl cellulose, sodium salt of carboxymethyl cellulose, polyacrylic acid and its salt, polymethacrylic acid and its salt, and organic materials such as starch. Compounds may be used. It is preferable to use 0.2 to 20 parts by weight of these dispersion stabilizers per 100 parts by weight of the polymerizable monomer.

When an inorganic compound is used as the dispersion stabilizer, a commercially available product may be used as it is, but the inorganic compound may be produced in an aqueous dispersion medium in order to obtain fine particles. For example, in the case of calcium phosphate, it is advisable to mix the sodium phosphate aqueous solution and the calcium chloride aqueous solution under high stirring.

For fine dispersion of the dispersion stabilizer, 0.001 to 0.1 part by weight of the surfactant may be used per 100 parts by weight of the polymer monomer. This is to promote the initial action of the dispersion stabilizer. Specific examples include sodium dodecylbenzene sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate, sodium oleate, sodium laurate, sodium octylate, sodium stearate, calcium oleate, and the like.

As the coloring agent used in the present invention, known coloring agents can be used.

Examples of black pigments include carbon black, aniline black, nonmagnetic ferrite, magnetite and the like.

Examples of yellow pigments include yellow iron oxide, Navels yellow, Naphthol yellow S, Hansah yellow G, Hansa yellow 10G, Benzidine yellow G, Benzidine yellow GR, quinoline yellow lake, permanent yellow NCG, tartrazine lake and the like. Can be mentioned.

Examples of orange pigments include permanent orange GTR, pyrazolone orange, vulcan orange, benzidine orange G, induslen brilliant orange RK, induslen brilliant orange GK and the like.

Examples of red pigments include red iron oxide, permanent red 4R, resole red, pyrazolone red, watching red calcium salt, lake red C, laked D, brilliant carmine 6B, brillant carmine 3B, eosin lake, rhodamine lake B, alizarin lake. Etc.

As blue pigments, alkali blue lake, Victoria blue lake, phthalocyanine blue,
Examples thereof include metal-free phthalocyanine blue, phthalocyanine blue partial chloride, fast sky blue, and indanthrene blue BG.

Examples of purple pigments include fast violet B and methyl violet lake.

Examples of green pigments include Pigment Green B, Malachite Green Lake, Final Yellow Green G and the like. As a white pigment, zinc white,
Examples thereof include titanium oxide, antimony white and zinc sulfide.

These colorants can be used alone or in a mixture, and can be used in the form of a solid solution.

The colorant used in the present invention is selected in terms of hue angle, saturation, brightness, weather resistance, OHP transparency and dispersibility in the toner. The addition amount of the coloring agent is 100
It is preferable to use 1 to 20 parts by weight with respect to parts by weight. When a magnetic material is used as the black colorant, it is preferable to use 30 to 150 parts by weight with respect to 100 parts by weight of the resin, unlike other colorants.

When the electrostatic latent image developing toner of the present invention is used as a light-transmitting color toner, various kinds of pigments of various colors can be used as a colorant.

For example, as a yellow pigment, C.I. I. 103
16 (naphthol yellow S), C.I. I. 11710
(Hansa Yellow 10G), C.I. I. 11660 (Hansa Yellow 5G), C.I. I. 11670 (Hansa Yellow 3G), C.I. I. 11680 (Hansa Yellow G),
C. I. 11730 (Hansa Yellow GR), C.I. I.
11735 (Hansa Yellow A), C.I. I. 11740
8 (Hansa Yellow RN), C.I. I. 12710 (Hansa Yellow R), C.I. I. 12720 (Pigment Yellow L), C.I. I. 21090 (benzidine yellow), C.I. I. 21095 (Benzidine Yellow G),
C. I. 21100 (benzidine yellow GR), C.I.
I. 20040 (Permanent Yellow NCR), C.I.
I. 21220 (Vulcan Fast Yellow 5), C.I.
I. 21135 (Vulcan Fast Yellow R) and the like.

As the red pigment, C.I. I. 12055
(Stalin I), C.I. I. 12075 (bread-manent orange), C.I. I. 12175 (Resole Fast Orange 3GL), C.I. I. 12305 (Permanent Orange GTR), C.I. I. 11725 (Hansa Yellow 3R), C.I. I. 21165 (Vulcan Fast Orange GG), C.I. I. 21110 (benzidine orange G), C.I. I. 12120 (Permanent Red 4
R), C.I. I. 1270 (Para Red), C.I. I. 12
085 (Fire Red), C.I. I. 12315 (Brilliant Fast Scarlet), C.I. I. 1231
0 (Permanent Red F2R), C.I. I. 12335
(Permanent red F4R), C.I. I. 12440
(Permanent red FRL), C.I. I. 12460
(Permanent red FRLL), C.I. I. 12420
(Permanent Red F4RH), C.I. I. 12450
(Light Fast Red Toner B), C.I. I. 124
90 (permanent carmine FB), C.I. I. 1585
0 (Brilliant Carmine 6B) and the like.

As the blue pigment, C.I. I. 74100
(Metal-free phthalocyanine blue), C.I. I. 74160
(Phthalocyanine blue), C.I. I. 74180 (Fast Sky Blue) and the like.

In the present invention, in order to produce toner particles by the polymerization method, it is necessary to pay attention to the polymerization inhibitory property and the water phase transfer property of the colorant. If necessary, the surface of the colorant may be subjected to a hydrophobic treatment with a substance that does not inhibit polymerization so as to modify the surface. In particular, attention must be paid to the use of dyes and carbon blacks because many of them have polymerization inhibitory properties.

As a preferable method for treating the dye, a method of previously polymerizing the polymerizable monomer in the presence of these dyes can be mentioned. The obtained colored polymer is added to the polymerizable monomer composition. In addition to carbon black, the carbon black may be treated with a substance that reacts with the surface functional groups of carbon black (eg, organosiloxane).

When the toner of the present invention is used as a magnetic toner, magnetic powder may be contained therein. As such a magnetic powder, a substance that is magnetized in a magnetic field is used. For example, a powder of a ferromagnetic metal such as iron, cobalt or nickel, or a powder of a sulfuric iron oxide such as magnetite or ferrite. There is.

In order to obtain toner particles by the polymerization method, it is necessary to pay attention to the polymerization inhibitory property and the water phase transfer property of the magnetic substance, and if necessary surface modification (for example, by a substance that does not inhibit polymerization). It is preferable that a hydrophobic treatment has been performed.

During the production process of the toner particles, the temperature may be raised in the latter half of the polymerization reaction, and further, in order to remove the unreacted polymerizable monomer or by-product which causes an odor at the time of fixing the toner, the reaction is performed. Part of the aqueous medium may be distilled off from the reaction system in the latter half or after the completion of the polymerization reaction. After the reaction is completed, the produced toner particles are washed, collected by filtration, and dried.

In the suspension polymerization method, it is preferable to use 300 to 3,000 parts by weight of water as a dispersion medium with respect to 100 parts by weight of the polymerizable monomer composition.

In order to clarify the functional separation of the inner or central part of the toner particles, the inner layer and the outer layer, the inner layer is higher than the endothermic main peak temperature of the DSC endothermic curve of the low softening point substance constituting the inner or central part. Hold the toner particles for 60 minutes or longer (preferably 90 to 600 minutes) at a temperature higher than the glass transition temperature of the constituent polymer or copolymer and higher than the glass transition temperature of the resin having a polar group constituting the outer layer. Heat treatment, and then 2 ℃ or less per minute (preferably,
It is better to cool slowly at a slow cooling rate of 1.5 to 0.25 ° C. per minute).

Therefore, the endothermic main peak temperature of the low softening point substance is measured in advance, the glass transition temperature of the resin having a polar group is measured, and the polymer or copolymer produced from the composition and composition ratio of the polymerizable monomer is measured. It is good practice to calculate the theoretical glass transition temperature of the polymer.

The heat treatment temperature is higher than the endothermic main peak temperature of the low softening point substance by 5 ° C. or more (preferably 5 to 20).
Higher than the glass transition point of the resin having a polar group added to the polymerizable monomer composition by 5 ° C. or more (preferably by 5 to 20 ° C. higher), and a polymer or copolymer synthesized. Higher than the theoretical glass transition point of 5 ° C. or more (preferably,
It is good to carry out at a temperature of 7.5 to 30 ° C. higher).

For higher image quality, it is preferable that the toner has a weight average diameter of 4 to 8 μm and a coefficient of variation A in the number distribution of 35% or less. Weight average diameter is 4 μm
If the weight average particle diameter of the toner is 8 μm or more, fusing to the surface of the photoconductor or the transfer material is likely to occur. When the coefficient of variation in the toner number distribution exceeds 35%, the tendency becomes even stronger.

Next, the present invention will be described more specifically with reference to Examples and Comparative Examples.

Example 1 710 parts by weight of ion-exchanged water and 850 parts by weight of a 0.1 mol / liter Na ₃ PO ₄ aqueous solution were added to a four-necked container, and a high-speed stirrer TK-Homomixer was used for 12, 0
The temperature was maintained at 60 ° C while stirring at 00 rpm. 68 parts by weight of 1.0 mol / liter-CaCl ₂ aqueous solution was gradually added to the mixture to obtain a fine, slightly water-soluble dispersion stabilizer Ca ₃ (PO
₄ ) An aqueous dispersion medium containing ₂ was prepared.

Styrene monomer 165 parts by weight n-butyl acrylate 35 parts by weight Copper phthalocyanine pigment 13 parts by weight Polyester resin 7 parts by weight (terephthalic acid-propylene oxide modified bisphenol A-ethylene oxide modified bisphenol A; acid value 13; glass transition point 60 ° C Mw12000, Mn5700) Negative charge control agent (chromium compound of dialkylsalicylic acid) 1 part by weight Low softening point compound [ester wax (3)] 25 parts by weight (endothermic main peak temperature in DSC 81 ° C, half width 3 ° C, Tangential desorption temperature 50 ° C .; Mw = 700, Mw / Mn = 1.2; melt viscosity at 100 ° C. 20 cPa · s)

The theoretical Tg of the styrene-n-butyl acrylate copolymer synthesized from styrene and n-butyl acrylate is 59 ° C.

The above mixture was dispersed for 3 hours using an attritor, and then 4 parts by weight of 2,2'-azobis (2,4-dimethylvaleronitrile) as a polymerization initiator was added to the polymerizable monomer composition. The product was put into an aqueous dispersion medium and granulated for 5 minutes while maintaining the rotation speed of the stirrer at 10,000 rpm. Then, the high-speed stirring device was changed to a propeller-type stirrer, the internal temperature was raised to 70 ° C., and the reaction was carried out for 10 hours while stirring slowly to obtain polymer particles (toner particles).

Then, the temperature inside the container was raised to 90 ° C. and the temperature was raised to 3
Hold for 00 minutes, then gradually cool at a cooling rate of 1 ° C per minute to 3
Cooled to 0 ° C. Dilute hydrochloric acid was added to the container to remove the dispersion stabilizer. Further, by filtering, washing and drying, electrically insulating cyan toner particles having a weight average diameter of 6.4 μm and a coefficient of variation in number distribution of 29% were obtained.

The obtained cyan toner particles are dyed with osmium tetroxide and ruthenium tetroxide, and a schematic view of a tomographic photograph confirmed by TEM is shown in FIG. Ester wax, which is a low softening point substance, constitutes the central part, and the central part is GPC
Has a molecular weight of 23,000 and a glass transition point (T
g. ) Was covered with an inner layer composed of a styrene-n-butyl acrylic copolymer having a temperature of 62 ° C., and an upper layer composed of a polyester resin having a thickness of about 0.15 μm was covered therewith.

2% by weight of hydrophobic titanium oxide fine particles were externally added to the obtained cyan toner particles to obtain a cyan toner having excellent fluidity. A two-component developer was prepared by mixing 6 parts by weight of the obtained cyan toner with 94 parts by weight of a ferrite carrier coated with a silicone resin having an average particle size of 40 μm.

An image is copied in the cyan color mode at room temperature and normal humidity and at room temperature and low humidity by using a modified machine which is a modification of the devital full color copying machine CLC-700 having a commercially available OPC photoconductor, using the above two-component developer. And evaluated. At room temperature and humidity, the transfer efficiency from the surface of the photosensitive drum is 97 at the initial stage.
%, And an image having a high image density free of transfer defects such as hollow defects was obtained. Although the durability test was performed on 50,000 sheets, the transfer efficiency always maintained a value close to 95%, and there was no significant change in the image quality between the initial stage and the durability test, and the toner was fused to the photosensitive drum and each member. Was not observed. The results under normal temperature and normal humidity were reproduced even under normal temperature and low humidity. The results are shown in Tables 3 and 4.

Toner particles are produced in the same manner as in Example 1 except that the materials used in Examples 2 to 7 and Comparative Examples 1 to 5 are shown in Table 1, and then a two-component developer is prepared. , An evaluation test was conducted. The results are shown in Tables 2, 3 and 4.

Comparative Example 6 The polymerization temperature was 70 ° C., and then the temperature was raised to 90 ° C.
Toner particles are produced in the same manner as in Example 1, except that the temperature is cooled from 90 ° C. to 30 ° C. at a cooling rate of 5 ° C./min.
Then, a two-component developer was prepared and an evaluation test was conducted. The results are shown in Tables 2, 3 and 4.

[0112]

[Table 1]

[0113]

[Table 2]

[0114]

[Table 3]

[0115]

[Table 4]

Measurement of Image Density Using a Macbeth densitometer, an SPI complementary color filter was used to measure a solid image portion.

Measurement of Transfer Efficiency The transfer efficiency was evaluated at the initial stage and after endurance of continuous image formation on 50,000 sheets. The cyan toner image formed on the photosensitive drum in the cyan unit was sampled with a transparent adhesive tape, and its image density (D ₁ ) was measured with a Macbeth densitometer. Next, a cyan toner image is formed again on the photosensitive drum, the cyan toner image is transferred to a recording material, the cyan toner image transferred on the recording material is sampled with a transparent adhesive tape, and its image density (D ₂ ) Was similarly measured. The image density (D ₁ ) and (D ₂ ) thus obtained were calculated as follows.

Transfer efficiency (%) = (D ₂ / D ₁ ) × 100

Presence / absence of fusion of toner on the surface of OPC photoreceptor After presence / absence test of 50,000 sheets in an environment of room temperature and low humidity (20 ° C., 5% RH), visual observation of presence / absence of fusion of toner on surface of OPC photoreceptor did. In addition, a halftone image is displayed and
It was judged whether or not an image defect due to toner fusion occurred, in comparison with a standard sample.

Evaluation of low temperature fixability and high temperature offset resistance
Method Transfer paper (80 g / m ² ) using a commercial full-color digital copier (CLC-700, Canon) modified
An unfixed toner image was formed on top. Next, the unfixed toner image was heated and pressed on the transfer paper without oil by an external fixing device of a heating / pressurizing roller which does not have an oil applying means and whose fixing temperature can be adjusted, thereby forming a fixed image on the transfer paper.

The fixing roller (heating roller) surface of the external fixing device is made of fluororesin and the pressure roller surface is also made of fluororesin. The nip of 5.5 mm,
120 to 2 at a fixing speed of 120 mm / sec
A fixing test was conducted at a temperature range of 40 ° C. at 5 ° C. intervals.

The low temperature fixability is such that the fixed image is 50 g / cm ^2.
The load of sillbon paper [Lenz Cleaning P
aper "dasper (R)" (Ozu Pap
erCo. Rdd]] was rubbed twice, and the temperature at which the density decrease rate before and after rubbing was less than 10% was defined as the fixing temperature and used for the evaluation of low-temperature fixability.

Rank of low temperature fixability: ⊚: 120 ° C. ≦ fixing start temperature ≦ 140 ° C .: 140 ° C. <fixing start temperature ≦ 160 ° C. Δ: 160 ° C. <fixing start temperature ≦ 180 ° C. ×: fixing start temperature <180 On the other hand, the high temperature offset resistance was determined by visually observing the fixed image and the surface of the fixing roller to determine whether high temperature offset occurred at each temperature.

Rank of high temperature offset resistance: ⊚: High temperature offset generation temperature ≧ 210 ° C .: 200 ° C. ≦ High temperature offset generation temperature <210 ° C. ΔΔ: 190 ° C. ≦ High temperature offset generation temperature <200 ° C. Δ: 180 ℃ ≦ high temperature offset generation temperature <190 ° C ×: high temperature offset generation temperature <180 ° C

Evaluation Method for Wrapping of Fixing Roller The temperature at which the solid image is fixed on the entire surface of the transfer paper (80 g / m ² ) and the transfer paper is wound around the fixing roller is set as the winding start temperature by using the external fixing device.

Fixing roller winding rank: ◯: winding start temperature ≧ 200 ° C. Δ: 180 ° C. ≦ winding start temperature <200 ° C. ×: winding start temperature <180 ° C.

Examples 8 to 10 Instead of the phthalocyanine pigment, a magenta colorant (C.I.
I. Pigment Red 122) 17 parts by weight, yellow colorant (CI Pigment Yellow 173) 13 parts by weight and black colorant (grafted carbon black) 15 parts by weight as in Example 1 except that magenta is used. Toner particles, yellow toner particles and black toner particles were produced. Table 5 shows the results.

Then, a two-component type developer for each color was prepared in the same manner as in Example 1.

[0129]

[Table 5]

Experimental Example Two-component developer for cyan of Example 1, two-component developer for magenta of Example 8, two-component developer for yellow of Example 9 and two-component system for black of Example 10. When an image output test was conducted in a full color mode using a developer, a full color image faithful to the original image was obtained.

The offset phenomenon did not occur even if silicone oil was not applied to the fixing roller, and no trouble occurred in the fixing process even when double-sided fixing was performed on plain paper.

[0132]

EFFECTS OF THE INVENTION The toner of the present invention is improved in durability, is coated with a polymer to thicken the fine irregularity of the charging property of the toner surface as in the prior art, and charges control material on the surface of toner particles. Instead of being prevented by adhesion, the inside or center of the low softening point compound is first covered with an inner layer, which is further covered with an upper layer. Then, the toner particles are embedded with an epoxy resin or the like, further, the cross section is stained with ruthenium tetraoxide and osmium trioxide, when the section is observed later using a transmission electron microscope, By constituting the materials capable of forming the inner layer and the upper layer by the materials identified as different from each other, the toner of the present invention has the colorant and the low softening point substance well encapsulated in the toner particles, and has excellent developing characteristics. And fixing characteristics can be exhibited.

[Brief description of drawings]

FIG. 1 is a schematic view showing a cross section of toner particles dyed with ruthenium tetraoxide and osmium trioxide.

FIG. 2 is a schematic diagram of a DSC curve of ester wax.

Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location G03G 9/08 381 384

Claims (38)

[Claims] 1. A toner for developing an electrostatic charge image, comprising toner particles containing at least a binder resin and a colorant, wherein the toner particles contain at least an internal low softening point substance, and A material having an inner layer coating the inner layer and an upper layer coating the inner layer and the inner layer, the inner layer, the inner layer and the upper layer being distinguishable by ruthenium trioxide and osmium trioxide staining method. A toner for developing an electrostatic charge image, comprising: 2. The low softening point compound forming the interior has a weight average molecular weight of 300 to 1,500, a weight average molecular weight / number average molecular weight ratio of 1.5 or less, and an endothermic main peak in a DSC endothermic curve. The toner according to claim 1, having a value of 55 to 120 ° C and a tangential desorption temperature of 40 ° C or higher. 3. The toner according to claim 1, wherein the inner layer is formed of a vinyl polymer or a vinyl copolymer. 4. The styrene polymer or styrene-having a glass transition point of more than 50 ° C. and less than 100 ° C. in the inner layer.
The toner according to any one of claims 1 to 3, which is formed of an acrylic copolymer or a styrene-methacrylic copolymer. 5. The toner according to claim 1, wherein the upper layer is formed of a polyester resin or its derivative. 6. The upper layer has a polyester resin produced from a bisphenol polyol having a glass transition point of 55 to 80 ° C. and an aromatic polyvalent carboxylic acid, according to claim 1. Toner. 7. The toner particles have a low softening point substance of 5 to 30.
7. The toner according to claim 1, wherein the toner is contained in a weight percentage. 8. The toner according to claim 1, wherein the upper layer has a thickness of 0.01 to 0.5 μm. 9. The toner particles have a shape factor SF-1 of 100.
The toner according to any one of claims 1 to 8, which has a particle size of 150 to 150. 10. The toner particles have a shape factor SF-1 of 10.
The toner according to claim 9, which is 0 to 125. 11. The toner has a weight average particle diameter of 3 to 8 μm.
11. The toner according to claim 1, wherein the number variation coefficient is 35% or less. 12. The toner according to claim 1, wherein the toner particles are polymerized toner particles directly produced by polymerizing a polymerizable monomer in an aqueous medium. 13. The low softening point substance forming the interior has a weight average molecular weight of 300 to 1,500, a weight average molecular weight / number average molecular weight ratio of 1.5 or less, and an endothermic main peak in a DSC endothermic curve. Has a value of 55 to 120 ° C., a tangential desorption temperature of 40 ° C. or higher, the inner layer is formed of a vinyl polymer or a vinyl copolymer, and the upper layer is formed of a polyester resin or a derivative thereof. The toner according to any one of claims 1 to 12. 14. The inner layer is formed of a styrene polymer, a styrene-acrylic copolymer, or a styrene-methacrylic copolymer having a glass transition point of more than 50 ° C. and less than 100 ° C., and the upper layer has a glass transition point. The toner according to claim 13, wherein the toner has a polyester resin formed from a bisphenol polyol aromatic polyvalent carboxylic acid having a temperature of 55 to 80 ° C. 15. The toner particles have a low softening point substance of 5 to 3.
The toner according to claim 13 or 14, which contains 0% by weight. 16. The toner particles are made of a substance having a low softening point of 10 to 3
The toner according to claim 15, which contains 0% by weight. 17. The upper layer has a thickness of 0.01 to 0.5 μm.
And the toner particles have a shape factor SF-1 of 100 to 15
The toner according to claim 15 or 16, which is 0. 18. The toner particles have a shape factor SF-1 of 10.
The toner according to claim 17, which is 0 to 125. 19. The toner has a weight average particle diameter of 3 to 8 μm.
19. The toner according to claim 18, wherein the number variation coefficient is 35% or less. 20. The toner of claim 19, wherein the toner particles are polymerized toner particles produced more directly by polymerizing a polymerizable monomer in an aqueous medium. 21. The low softening point substance is an ester wax, and the value of the endothermic main peak in the DSC endothermic curve is at a temperature of 60 to 90 ° C., and the half width of the endothermic main peak is within 10 ° C. 21. The toner according to any one of 20 to 20. 22. The toner according to claim 21, wherein the ester wax has an endothermic main peak value at a temperature of 60 to 85 ° C., and a half-value width of the endothermic main peak is within 5 ° C. 23. A polymerizable monomer composition containing at least a polymerizable monomer, a colorant, a low softening point substance, a resin having a polar group, and a polymerization initiator is prepared. Is dispersed in an aqueous medium to produce particles of the polymerizable monomer composition, and the polymerizable monomer in the particles is polymerized to produce toner particles, which is lower than the endothermic main peak temperature of the low softening point substance. The aqueous medium is heated to 5 ° C. or more and 5 ° C. or more higher than the glass transition temperature of the resin having a polar group, and then the aqueous medium is cooled to 50 ° C. or less at a cooling rate of 2 ° C. or less per minute to obtain a toner. A method for producing a toner in which particles are separated from an aqueous medium to produce toner particles, wherein the toner particles include at least a low softening point substance forming the inside, an inner layer coating the inside, and the inside And an upper layer covering the inner layer, A method for producing a toner, wherein the inner layer and the upper layer are made of a material which can be identified by a ruthenium tetraoxide and an osmium tetraoxide dyeing method. 24. After polymerization of the polymerizable monomer, 5 ° C. higher than the theoretical glass transition temperature of the polymer or copolymer of the polymerizable monomer.
24. The method for producing a toner according to claim 23, wherein the aqueous medium is heated to the higher temperature. 25. The low softening point compound forming the interior has a weight average molecular weight of 300 to 1,500, a weight average molecular weight / number average molecular weight ratio of 1.5 or less, and an endothermic main peak in a DSC endothermic curve. The method for producing a toner according to claim 23 or 24, wherein the value of is from 55 to 120 ° C, and the tangential desorption temperature is 40 ° C or higher. 26. The method for producing a toner according to claim 23, wherein the inner layer is formed of a vinyl polymer or a vinyl copolymer. 27. The inner layer is formed of a styrene polymer, a styrene-acryl copolymer, or a styrene-methacryl copolymer having a glass transition point of higher than 50 ° C. and lower than 100 ° C. The method for producing a toner according to any one of claims. 28. The method for producing a toner according to claim 23, wherein the upper layer is formed of a polyester resin or a derivative thereof. 29. The upper layer comprises a polyester resin produced from a bisphenol-based polyol having a glass transition point of 55 to 80 ° C. and an aromatic polyvalent carboxylic acid, according to claim 23. Toner manufacturing method. 30. The toner particles contain a low softening point substance of 5 to 3.
30. The method for producing a toner according to claim 23, wherein the toner contains 0% by weight. 31. The upper layer has a thickness of 0.01 to 0.5 μm.
31. The toner manufacturing method according to claim 23. 32. The toner particles have a shape factor SF-1 of 10.
32. The method for producing a toner according to claim 23, wherein the toner is 0 to 150. 33. The toner particles have a shape factor SF-1 of 10.
The method for producing a toner according to claim 32, wherein the toner is 0 to 125. 34. The toner has a weight average particle diameter of 3 to 8 μm.
34. The method for producing a toner according to claim 23, wherein the number variation coefficient is 35% or less. 35. The low softening point substance forming the interior has a weight average molecular weight of 300 to 1,500, a weight average molecular weight / number average molecular weight ratio of 1.5 or less, and an endothermic main peak in a DSC endothermic curve. Has a value of 55 to 120 ° C., a tangential desorption temperature of 40 ° C. or higher, the inner layer is formed of a vinyl polymer or a vinyl copolymer, and the upper layer is formed of a polyester resin or a derivative thereof. The method for producing a toner according to claim 23. 36. The inner layer is formed of a styrene polymer, a styrene-acryl copolymer or a styrene-methacryl copolymer having a glass transition point of more than 50 ° C. and less than 100 ° C., and the upper layer is a glass transition point. The polyester resin produced from bisphenol polyol and aromatic polyvalent carboxylic acid having a temperature of 55 to 80 ° C.
5. The method for producing a toner according to any one of 1. 37. The low softening point substance is an ester wax, the endothermic main peak value in the DSC endothermic curve is at a temperature of 60 to 90 ° C., and the full width at half maximum of the endothermic main peak is within 10 ° C. 37. The method for manufacturing a toner according to any one of 36 to 36. 38. The method for producing a toner according to claim 37, wherein the ester wax has a heat absorption main peak value at a temperature of 60 to 85 ° C., and a half width of the heat absorption main peak is within 5 ° C.