JPH11190913A - Electrostatic charge image developing toner and electrophotographic developer using that - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrostatic charge image developing toner especially suitable for a heat roll fixing method. SOLUTION: This electrophotographic toner is prepared by dispersing a coloring agent in a binder resin. The binder resin has a softening point of 70 to 85 deg.C, a flowing initiation temp. of 110 to 125 deg.C, 145 to 160 deg.C F1/2 temp. and 150 to 180 deg.C final temp. when measured by an overhead flow tester. The binder resin preferably consists of a polyester resin having a polycarboxylic acid component (A) and a polyol component (B) as the structural units or consists of this polyester resin blended with a vinyl resin.

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 image in electrophotography, electrostatic recording, electrostatic printing, etc., and relates to an electrostatic image suitable for a copying machine having a heat roll fixing mechanism. The present invention relates to a developing toner and an electrophotographic developer using the same.

[0002]

2. Description of the Related Art Since a developing toner used in a copying machine having a fixing mechanism of a heating roller contacts a surface of the heating roller under pressure in a dissolved state with a toner image, a part of the toner image is formed on the surface of the roller. To cause a paper offset phenomenon. As means for avoiding the offset phenomenon, a toner using a crosslinked polymer as a fusion resin (Japanese Patent Publication No. 51-23354) and a toner containing a low molecular weight polyolefin such as polypropylene and polyethylene (Japanese Patent Application Laid-open No. No. 49-6523) have been proposed. These methods are effective in improving the offset resistance and the abrasion resistance, but have not been satisfactory at the same time with respect to the fixing property. Further, in the olefin-containing toner, the olefin is relatively soft, so that the olefin is liberated by a slight force, and the olefin is attached to the surface of the carrier particles and contaminated. This contamination greatly impairs the triboelectric charging property between the toner and the carrier. As a result, charging instability occurs at an early stage, and fogging is observed in an image. Further, since the toner containing olefin has low fluidity, the supply amount of the toner to the developing unit becomes unstable, and image unevenness is likely to occur.

Conventionally, in the heating roller fixing method, in order to prevent toner from adhering to the surface of the fixing roller,
For example, the surface of the fixing roller is formed of a material such as fluorine resin that has excellent release properties from toner, and an anti-offset liquid such as silicone oil is further supplied to the surface to coat the roller surface with a thin film of liquid. That is being done. Although this method is extremely effective in preventing offset of the toner, it generates an odor when the offset preventing liquid is heated, and requires an apparatus for supplying the offset preventing liquid. The mechanism of the copying apparatus becomes complicated, and high accuracy is required to obtain a stable image, so that the copying apparatus is expensive.

It is more difficult to obtain a toner free from the offset phenomenon when considering application to a high-speed copying machine using a heat roll without using much electric power for a fixing device, that is, a so-called labor-saving high-speed copying machine. Meet the problem. That is, in order for the offset phenomenon not to occur, the binder polymer used in the toner is required to be as tough as possible and have sufficient melt fluidity. However, in order to have melt fluidity, the toner must be heated to a considerably high temperature, which does not satisfy the demand for labor saving. Therefore, in order to save labor, fixing at a low temperature is required, and it is preferable to use a resin having a low glass transition point and a low molecular weight. However, a resin having a low molecular weight naturally has no toughness and easily causes an offset phenomenon.

Heretofore, toughening of the toner for preventing offset has generally used a high-molecular polymer having an average molecular weight of about 100,000 or more, especially a vinyl polymer in many cases. In order to fix a toner using a high molecular weight vinyl polymer at a low temperature, there are methods such as lowering the glass transition point of the polymer as low as possible without blocking, or lowering the fixing temperature by adding a plasticizer. However, these methods not only lower the fixing point (the lowest temperature at which complete fixing is performed), but also lower the hot offset temperature (the temperature at which offset starts to occur). , The so-called fusing latitude is merely moved to the lower temperature side. Also, if an attempt is made to prevent a decrease in the hot offset temperature due to an increase in the weight average molecular weight, the viscosity of the resin increases,
The effects of lowering the glass transition point and adding a plasticizer are diminished, and furthermore, the pulverizability is deteriorated due to the large amount of crosslinked components.

On the other hand, a polyester resin has a low glass transition point, unlike a vinyl polymer, and can easily obtain a resin having a low molecular weight. This means that a low-temperature fixing toner can be easily obtained. However,
Since the polyester resin is a low molecular weight resin, the degree of offset is high and the polyester resin cannot be used as it is for a heat roll toner.

Therefore, in order to take advantage of both the property that the vinyl polymer does not cause offset up to a high temperature and that the polyester can be fixed even at a low temperature, it is conceivable to blend both resins. No. 54-114245. However, a high-molecular-weight vinyl polymer and a low-molecular-weight polyester resin are poorly compatible with each other, resulting in a non-uniform dispersion state. In particular, as the molecular weights of the two differ, the compatibility deteriorates, and when the dispersion state is observed with a phase contrast microscope or the like, the dispersion state is observed as if there are islands in the sea. This is also observed when blending poorly compatible plastics. As a sea-island theory, Plastics, 13, No. 9, 1 (1
962).

When the above-mentioned sea-island is formed in the toner resin, the other components of the toner, such as a polarity controlling agent such as a dye and a coloring agent such as carbon black and a magnetic material, become insufficiently dispersed. In the repeated copying, oppositely charged toner and the like are generated, and so-called fogging occurs. On the other hand, in order to improve the dispersibility of the polyester resin and the vinyl polymer, a method has been proposed in which a common segment is introduced into both to form a graft copolymer. However, such a resin is averaged without taking advantage of each other's advantages of hot offset resistance and low-temperature fixability.

[0009]

SUMMARY OF THE INVENTION A first object of the present invention is to provide a toner for developing an electrostatic charge image which is suitable for a hot roll fixing system, can be fixed at a low temperature, and has excellent hot offset properties, and an electrophotography using the same. To provide a developer for use in a computer. A second object of the present invention is to provide a toner capable of improving the wax dispersibility and the pigment dispersibility at the time of production, improving the productivity, and obtaining excellent image quality, and an electrophotographic developer using the toner. It is in. Third of the present invention
The object of the present invention is to provide a toner capable of exhibiting high productivity (pulverizability of raw materials) by providing a binder resin having a small power load at the time of kneading toner in a pulverized toner production line, and an electrophotographic developer using the same. To provide. A fourth object of the present invention is to provide a toner having good charging and environmental stability, and an electrophotographic developer using the same.

[0010]

According to the present invention, (1)
In a toner for developing an electrostatic image formed by dispersing a colorant in a binder resin, a softening temperature measured by an elevated flow tester is 70 to 85 ° C., and an outflow start temperature is 110 to 125.
° C, an F1 / 2 outflow temperature of 145 to 160 ° C, and an outflow end temperature of 150 to 180 ° C.

According to the present invention, (2) the above (1)
That the binder resin contained in the toner does not contain a tetrahydrofuran (THF) -insoluble component, and that the component having a molecular weight of 1 × 10 ⁷ or more has a
(3) In the toner for developing an electrostatic image according to the above (1) or (2), the binder resin is a gel permeation chromatograph of a THF-soluble part thereof. In the molecular weight distribution according to the graph (GPC), a main peak is in a region of 2,000 to 10,000, and a molecular weight of 10,000 or less is 50 to 70%.
(4) a toner for developing an electrostatic charge image,
In the toner for developing an electrostatic charge image according to the above (1), (2) or (3), the binder resin used for the toner is a polyester resin or a vinyl resin (not more than 30% by weight of the entire binder resin). (5) a toner for developing electrostatic images, characterized by blending:
In the toner (1), (2), (3) or (4), the binder resin has a water content of 30 ° C.
5000 ppm or less (% in 24 hours), preferably 3%
(6) The toner for developing an electrostatic image according to (1), (2), (3), (4) or (5), wherein the toner contains wax. (7) The electrostatic image of (1), (2), (3), (4), (5) or (6), wherein the wax has a dispersed particle size of 2 μm or less. A magnetic one-component toner comprising magnetic particles having a particle diameter of 0.1 μm or less in a developing toner; (8) a carrier particle coated with a silicone resin on the surface; and (1) (2) (3) (4) An electrophotographic developer characterized by being mixed with the electrostatic image developing toner of (4), (5) or (6).

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail. The fixability of the hot roll fixing toner is closely related to the melting viscoelasticity of the toner, and a binder resin having low thermal characteristics is suitable for satisfying low-temperature fixing. Conventionally,
As an index of the thermal characteristics, characteristics of a flow tester, a melt index, and a rheometer are used. On the other hand, in order to satisfy hot offset which is inconsistent with low-temperature fixability,
As a property of the toner, various waxes are used as a binder resin having higher elasticity or a release material.
As a characteristic, viscoelasticity by a rheometer has been conventionally measured. The present inventors have found that there is an optimum range in the temperature curve of the flow tester as an index for satisfying the low-temperature fixing property and the hot offset property and expanding the fixing temperature range width. As an example of the flow tester, there is an “elevated flow tester CFT500 type” manufactured by Shimadzu Corporation. The flow curve of this flow tester is shown in Fig.1 (a) (b)
And the respective temperatures can be read therefrom. In the figure, Ts is the softening temperature, Tfb is the outflow starting temperature, and the melting temperature in the 1/2 method is the F1 / 2 temperature.

Conventionally, the value of each temperature was read and used as a thermal characteristic index of the toner or the binder resin. The four temperatures (Ts,
Tfb, F1 / 2 temperature, outflow end point) satisfy the low-temperature fixing and the hot offset. Table 1 shows the relationship between the flow curve and the toner quality.

[0014]

[Table 1] (Conditions) Load: 10 kg / cm ² , nozzle diameter: 1 mm, nozzle length: 1 mm, heating rate: 10 ° C / min

The toner for developing an electrostatic image of the present invention is obtained by blending a vinyl resin with a polyester resin or a polyester resin as a binder resin in an amount of 30% or less. The binder resin preferably satisfies the following conditions (A) and (B). (A) Tetrahydrofuran (THF) insoluble matter should not be contained. (B) 5 to 20% of a component having a molecular weight of 1 × 10 ⁷ or more. Here, the states (a) and (b) can be obtained by molecular cutting by mechanical shearing energy in the kneading step in toner production. These states (a) and (b) will be referred to as microgel components. The reason why the molecular weight is 1 × 10 ⁷ or more in the above (b) is that a molecular weight of 1 × 10 ⁷ or more cannot be measured at present.

The toner of the present invention has a main peak in a region where the weight average molecular weight is 2,000 to 10,000 in the molecular weight distribution by GPC of THF dissolved in the binder resin, and contains 50 to 70% of a molecular weight of 10,000 or less. Thereby, the pulverizability and the low-temperature fixability are improved. TH
The presence of F-insoluble component or 2 components with a molecular weight of 1 × 10 ⁷ or more
If it exceeds 0%, the fixability and the dispersibility of pigments and waxes are reduced. Further, the use of an aromatic material as a monomer is effective in reducing the environmental stability characteristic of polyester resin, which is less susceptible to moisture in the air. (T
g) to 50-65 ° C., acid value and hydroxyl group are reduced as much as possible, acid value is 1-5 mgKOH / g, and hydroxyl value is 30-8.
When the content is in the range of 0 mgKOH / g, the low-temperature fixability is further improved, and the charging stability in a high-temperature environment is improved. In addition, when the vinyl resin is blended in an amount of 30% by weight or less of the resin system, the environmental friendliness of the vinyl resin is further improved as compared with the case where the polyester resin is used alone. At this time, the water content of the binder resin is (30 ° C., 60%, 24 hours humidity control)
5,000 ppm or less (preferably 3,000 or less) further improves the charging stability in a high-temperature environment.

In addition to the above, it is advantageous to add a wax having an effect on the releasability as a means for further improving the hot offset property. However, as wax increases, it causes problems such as spent with a carrier and reduced charge due to reduced dispersibility with a charge controlling agent. Therefore, it is desirable to prevent the spent by setting the dispersed particle diameter of the wax to 2 μm or less.

Conventionally, in the production of toner, the balance between the fixing property, the pulverizability, and the hot offset has been achieved by devising the ratio of the crosslinked portion (measured as a THF insoluble portion) and the ratio of the THF soluble portion. The relationship between the pulverizability based on the molecular weight distribution, the fixing property, and the hot offset can be separated into an insoluble component and a soluble component when the binder resin is dissolved in a solvent such as THF. Can be measured.

Focusing on the peak positions and the component amounts of the molecular weight distribution of the THF-insoluble portion and the soluble portion, the THF-insoluble portion is disadvantageous for the fixing property but is effective for hot offset. If the amount of insolubles is too large, the load is too high when kneading the toner with a kneading machine, so that the supply amount of the material must be reduced, which results in poor productivity and easy variation in quality.

Although several toners using a binder resin having a molecular weight range of less than 1 × 10 ⁷ have been known, none of them have been satisfactory. As a result of research on these, the present inventors have already mentioned a little about grindability and fixability based on a new molecular weight distribution, hot offset, and the like, and have found the following facts. As a result, with respect to the environmental stability of charging, which is a problem of the polyester resin, the binder resin of the blend type of the polyester resin and the vinyl resin in the present invention is improved to suppress the humidity dependency, and to obtain a toner showing good charging characteristics. It has been reached.

Here, the measuring method by GPC will be described as follows. That is, the column was stabilized in a heat chamber at 40 ° C., and THF was flowed through the column at this temperature at a flow rate of 1 ml per minute as a solvent.
The measurement is performed by injecting 50 to 200 μl of the HF sample solution. In measuring the molecular weight of a sample, the molecular weight distribution of the sample is calculated from the relationship between the logarithmic value of a calibration curve created from several types of monodisperse polystyrene standard samples and the count number. As a standard polystyrene sample for preparing a calibration curve, for example, P
less Chemical Co. Alternatively, Toyo Soda Kogyo Co., Ltd. has a molecular weight of 6 × 10 ² , 2.1 × 10 ³ , 4
× 10 ³ , 1.75 × 10 ⁴ , 5.1 × 10 ⁴ , 1.1 ×
10 ⁵ , 3.9 × 10 ⁵ , 8.6 × 10 ⁵ , 2 × 10 ⁶ ,
It is appropriate to use 4.48 × 10 ⁶ samples and to use at least about 10 standard polystyrene samples. An RI (refractive index) detector is used as the detector. Although in this way is not to measure the molecular weight distribution of the toner, the detection of molecular weight ¹⁰⁷ or more in the current column is substantially difficult.
On the other hand, the existence of a molecular weight range of 10 ⁷ or more, which is the detection limit of GPC molecular weight measurement in the THF-soluble portion, that is, a microgel component was discovered, and this molecular range was found to have fixability, grindability,
Influencing the offset. The microgel content can be determined by using a toner separation method. That is, a solvent insoluble in toner is added to THF, and the ratio of THF to the solvent may be determined while observing the molecular weight distribution.

This time, fractionation was carried out at 25 ° C. using a mixed solvent of THF and isododecane. The ratio (volume ratio) of THF / isododecane is suitably 2 ± 0.5 / 3 ± 1.5, and the liquid in which the toner is dissolved at this ratio is the range for measuring the molecular weight of GPC. In addition, a test method for separating and separating the THF insoluble matter is performed as follows. Toner about 1.0
weighed, and about 50 g of THF was added thereto.
Let stand for a while. This is first separated by centrifugation and filtered at room temperature using JIS standard (according to P3801) 5 type C quantitative filter paper. Subsequently, the filter paper residue is an insoluble matter, and is represented by the ratio (wt%) between the used toner and the filter paper residue. Since carbon and other solids are present in this residue, it is separately determined by thermal analysis. In the case of a solvent for separation, THF may be changed to this solvent. The microgel content can be calculated by calculating the THF / isododecane soluble content and the THF insoluble content from the amount of the THF soluble component.

The binder resin in the present invention is preferably a polyester resin containing a polycarboxylic acid component (A) and a polyol component (B) as constituent units, and a resin blended with a vinyl resin at 30% by weight or less. It is. The polycarboxylic acid component (A) includes a divalent carboxylic acid (A1) and, if necessary, a trivalent or higher carboxylic acid (A).
2).

Specific examples of the divalent carboxylic acids (A1) include (1) maleic acid, fumaric acid, succinic acid, adipic acid, sebacic acid, malonic acid, azelaic acid, mesaconic acid, citraconic acid, glutaconic acid and the like. An aliphatic dicarboxylic acid having 2 to 20 carbon atoms; (2) an alicyclic dicarboxylic acid having 8 to 20 carbon atoms such as cyclohexanedicarboxylic acid and methylmedic acid; (3) phthalic acid, isophthalic acid, terephthalic acid, and toluenedicarboxylic acid; An aromatic dicarboxylic acid having 8 to 20 carbon atoms such as naphthalenedicarboxylic acid; (4) an alkyl or alkenyl succinic acid having a hydrocarbon group having 4 to 35 carbon atoms in a side chain such as isododecenyl succinic acid or n-dodecenyl succinic acid; Acids; and anhydrides and lower alkyl (methyl, butyl, etc.) esters of these divalent carboxylic acids. Among these, (1), (3),
(4) and anhydrides and lower alkyl esters of these dicarboxylic acids are preferred, and maleic acid, fumaric acid, isophthalic acid, terephthalic acid, dimethyl terephthalate, and n-dodecenyl (anhydride) succinic acid are more preferred.
(Anhydride) maleic acid and fumaric acid are preferred in terms of high reactivity, and isophthalic acid and terephthalic acid are preferred in terms of increasing the glass transition temperature of the polyester. Also,
Alkyl or alkenyl (anhydride) succinic acid has the advantage of improving the pulverizability of the toner.

Specific examples of the trivalent or higher polycarboxylic acids (A2) include (1) 1,2,4-butanetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, and 1,3-dicarboxyl-2. -Methyl-2-methylenecarboxypropane, tetra (methylenecarboxyl) methane, 1,
7 to 7 carbon atoms such as 2,7,8-octanetetracarboxylic acid
(2) an alicyclic polycarboxylic acid having 9 to 20 carbon atoms such as 1,2,4-cyclohexanetricarboxylic acid; (3) 1,2,4-benzenetricarboxylic acid; 2,5-benzenetricarboxylic acid, 2,
5,7-naphthalenetricarboxylic acid and 1,2,4-
C9 to C20 aromatic polycarboxylic acids such as naphthalenetricarboxylic acid, pyromellitic acid and benzophenonetetracarboxylic acid; and anhydrides and lower alkyl (methyl, butyl, etc.) esters thereof. (A2)
When (3) is used, (3) and anhydrides and lower alkyl esters thereof are preferable among them, and in particular, 1,2,4-
Benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, and anhydrides and lower alkyl esters thereof are preferred in terms of cost and imparting offset resistance to the toner. The use ratio of (A2) in the polycarboxylic acid component (A) is usually 0 to 30 mol%, preferably 0 to 20 mol%,
More preferably, it is 0 to 10 mol%.

On the other hand, the polyol component (B) comprises a dihydric alcohol (B1) and, if necessary, a trihydric or higher alcohol (B2).

Examples of the dihydric alcohols (B1) include (1) ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, neopentyl glycol, 1,4-butene C2-C12 alkylene glycols such as diol, 1,5-pentanediol and 1,6-hexanediol; (2) diethylene glycol, triethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, etc. Alkylene ether glycols of (3)
Alicyclic diols having 6 to 30 carbon atoms such as 1,4-cyclohexanedimethanol and hydrogenated bisphenol A; and (4) bisphenols such as bisphenol A, bisphenol F and bisphenol S; and (5) the above bisphenols Alkylene oxides (EO, PO,
2-8 mol adducts of butylene oxide and the like). Of these, (1) and (5) are preferred,
(5) is more preferred. In the above (1), ethylene glycol increases the reaction rate, and 1,2-propylene glycol and neopentyl glycol are preferred from the viewpoint of low-temperature fixability. In the above (5), in particular, ethylene oxide (EO) of bisphenol A and / or 1,2
-A propylene oxide (PO) 2 to 4 mol adduct is preferred in that it gives the toner good offset resistance.

Specific examples of the trihydric or higher alcohols (B2) include (1) sorbitol, 1,2,3,6-hexane tetrol, 1,4-sorbitan, pentaerythritol, dipentaerythritol and tripenta Erythritol, 1,2,4-butanetriol, 1,2,5-
Aliphatic polyhydric alcohols having 3 to 20 carbon atoms such as pentanetriol, glycerol, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, and trimethylolpropane; (2)
C6 to C20 aromatic polyhydric alcohols such as 1,3,5-trihydroxylmethylbenzene; and alkylene oxide adducts thereof. (B
When 2) is used, among them, the compound of (1) is preferable, and among them, glycerol, trimethylolpropane and pentaerythritol are preferable from the viewpoint of inexpensiveness. The proportion of (B2) used in the polyol component (B) is as follows:
It is usually 0 to 20 mol%, preferably 0 to 10 mol%, more preferably 0 to 5 mol%.

The vinyl resin (vinyl polymer) which is blended with the polyester resin in the amount of 30% by weight or less based on the whole binder resin in the present invention contains 50 to 100% by weight, preferably 60% by weight of styrene as a component thereof.
It is preferable to use a vinyl copolymer polymerized by about 90% by weight. When the styrene copolymerization amount is less than 50% by weight, the heat melting property of the toner is inferior, and as a result, the fixing property tends to be insufficient.

In the present invention, the vinyl monomer other than styrene as a component of the vinyl polymer includes styrene such as α-methylstyrene, p-methylstyrene, p-tert-butylstyrene and p-chlorostyrene. Derivatives,
Methacrylic acid, methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, pentyl methacrylate, hexyl methacrylate, heptyl methacrylate, octyl methacrylate, nonyl methacrylate, decyl methacrylate, undecyl methacrylate, dodecyl methacrylate , Glycidyl methacrylate, methoxyethyl methacrylate, propoxyethyl methacrylate, butoxyethyl methacrylate, methoxydiethylene glycol methacrylate, ethoxydiethylene glycol methacrylate, methoxyethylene glycol methacrylate, butoxytriethylene glycol methacrylate,
Methoxydipropylene glycol methacrylate, phenoxyethyl methacrylate, phenoxydiethylene glycol methacrylate, phenoxytetraethylene glycol methacrylate, benzyl methacrylate, cyclohexyl methacrylate, tetrahydrofurfuryl methacrylate, dicyclopentenyl methacrylate, dicyclopentenyl methacrylate Ethyl, N-vinyl-2-pyrrolidone methacrylate, methacrylonitrile, methacrylamide, N-methylol methacrylamide, 2-hydroxyethyl methacrylate, hydroxypropyl methacrylate, hydroxybutyl methacrylate, methacrylic acid-
2-hydroxy-3-phenyloxypropyl, diacetone acrylamide, acrylic acid, methyl acrylate,
Ethyl acrylate, propyl acrylate, butyl acrylate, pentyl acrylate, hexyl acrylate, heptyl acrylate, octyl acrylate, nonyl acrylate, decyl acrylate, undecyl acrylate, dodecyl acrylate, glycidyl acrylate, acrylic acid Methoxyethyl, propoxyethyl acrylate, butoxyethyl acrylate, methoxydiethylene glycol acrylate, ethoxydiethylene glycol acrylate, methoxyethylene glycol acrylate, butoxytriethylene glycol acrylate, methoxydipropylene glycol acrylate, phenoxyethyl acrylate, acrylic acid Phenoxydiethylene glycol, phenoxytetraethylene glycol acrylate, benzyl acrylate, acrylic acid Rohekishiru, tetrahydrofurfuryl acrylate, acrylic acid dicyclopentenyl, dicyclopentenyloxyethyl acrylate, N-
Vinyl-2-pyrrolidone, hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxybutyl acrylate, 2-hydroxy-3-phenyloxypropyl acrylate, glycidyl acrylate, acrylonitrile, acrylamide, N-methylol acrylamide, diacetone acrylamide, 1 such as vinylpyridine
A vinyl monomer having one vinyl group in the molecule is used as a main component. In addition, a reaction product of divinylbenzene, glycol and methacrylic acid or acrylic acid, for example, ethylene glycol dimethacrylate, 1,3-butylene glycol Methacrylate, 1,4-butanediol dimethacrylate, 1,5-pentanediol dimethacrylate, 1,6-hexanediol dimethacrylate, neopentyl glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, Tripropylene glycol dimethacrylate, neopentyl glycol hydroxypivalate diester methacrylate, trimethylolethane trimethacrylate, Limethylolpropane trimethacrylate, pentaerythritol trimethacrylate, pentaerythrit tetramethacrylate, trismethacryloxyethyl phosphate, bis (methacryloyloxyethyl) hydroxyethyl isocyanurate, tris (methacryloyloxyethyl) isocyanurate, ethylene glycol diacrylate, 1 1,3-butylene glycol diacrylate, 1,4-butanediol diacrylate, 1,5-pentanediol diacrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate , Polyethylene glycol diacrylate, tripropylene glycol diacrylate, Dorokishipibarin acid neopentyl glycol diacrylate, trimethylol ethane triacrylate, trimethylol propane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, trisacryloxyethyl phosphate, bis (methacryloyloxyethyl) hydroxyethyl isocyanurate,
Tris (methacryloyloxyethyl) isocyanate, a half esterified product of glycidyl methacrylate and methacrylic acid or acrylic acid, a half esterified product of bisphenol type epoxy resin and methacrylic acid or acrylic acid,
A vinyl monomer having two or more vinyl groups in one molecule, such as glycidyl acrylate and methacrylic acid or half-esterified acrylic acid, is used.

Of these, preferred vinyl monomers include one vinyl monomer in one molecule.
In a vinyl monomer having one vinyl group in the molecule,
Examples thereof include styrene, styrene derivatives, methacrylic acid esters, and acrylic acid esters, and particularly preferred are styrene and alkyl esters of methacrylic acid or acrylic acid having 1 to 5 carbon atoms in the alkyl group. As the vinyl monomer having two or more vinyl groups in one molecule, divinylbenzene, dimethacrylate of methylene glycol having 2 to 6 carbon atoms, diacrylate and the like are preferable.

These monomers are blended so that the total is 100% by weight. Among them, the amount of the vinyl monomer having two or more vinyl groups in one molecule is preferably 0.1 to 1% by weight.

The above-mentioned monomer or monomer mixture can be polymerized by any method such as suspension polymerization, solution polymerization, emulsion polymerization, bulk polymerization and the like. From the point of view, it is preferred to produce by aqueous suspension polymerization.

The radical initiator used for the polymerization of the above monomer or monomer mixture includes benzoyl peroxide,
2-ethylhexyl perbenzoate, lauroyl peroxide, acetyl peroxide, isobutyryl peroxide, octanoyl peroxide, di-tert-butyl peroxide, tert-butyl peroxide, cumene hydroperoxide, methyl ethyl ketone peroxide, 4,4,6-trimethylcyclohexanone Di-tert-butylperoxyketal, cyclohexanone peroxide, methylcyclohexanone peroxide, acetylacetone peroxide,
Peroxide radical initiators such as cyclohexanone di-tert-butyl peroxy ketal, 2-octanone di-tert-butyl peroxy ketal, acetone di-tert-butyl peroxy ketal, diisopropyl benzene hydroperoxide, 2,2'-azobisiso Butyroitrile, 2,2′-azobis (2,4-dimethylpareronitrile), 2,2′-azobis (4-methoxy-2,4-dimethylvaleronitrile), dimethyl 2,2′-azobisisobutyrate, There are azobis-based radical initiators such as 1,1′-azobis (cyclohexane-1-carbonitrile). These are preferably 0.01 to 20% by weight, particularly preferably 0.1 to 20% by weight, based on the total amount of the monomers.
Use 1 to 10% by weight.

In addition, butyl mercaptan, octyl mercaptan, dodecyl mercaptan, methyl 2
-Mercaptopropionate, ethyl 2-mercaptopropionate, butyl 2-mercaptopropionate, octyl 2-mercaptopropionate, pentaerythritol tetra (2-mercaptopropionate),
Uses radical polymerization molecular weight regulators such as mercaptans such as ethylene glycol di (2-mercaptopropionate) and glycerin tri (2-mercaptopropionate), and halogenated hydrocarbons such as chloroform, bromoform and carbon tetrabromide. You can also. These molecular weight modifiers are preferably used in an amount of 0 to 3% by weight based on the total amount of the monomers.

When carrying out aqueous suspension polymerization, partially saponified polyvinyl alcohol, alkyl cellulose, hydroxy-alkyl cellulose, carboxyalkyl cellulose, polyacrylamide, polyvinylpyrrolidone,
Water-soluble polymer dispersants such as polyacrylic acid and its alkali metal salts, polymethacrylic acid and its alkali metal salts,
Insoluble inorganic dispersants such as calcium phosphate, hydroxyapatite, magnesium phosphate, magnesium pyrophosphate, calcium carbonate, barium sulfate, and hydrophobic silica can be used. The dispersant is preferably used in an amount of 0.0001 to 5% by weight based on the aqueous medium in the case of a water-soluble polymer dispersant, and 0.01 to 15% by weight in an aqueous medium in the case of a poorly soluble inorganic dispersant. preferable.

By the way, a toner using a polyester resin as a binder resin has a change in charge amount at high humidity and a slow rise in charge, and the like.
Such inconveniences have been reported. Slow charging rise may cause soiling. Therefore, it is necessary and indispensable to prevent these problems and obtain a clear image.

For these reasons, in the toner of the present invention, the binder resin (polyester resin, polyester resin blended with vinyl resin) has a Tg of 50 to 65 ° C. and an acid value of 1 to 5 mgKOH / g, preferably 1 to 5 mgKOH / g. ~ 3mgKOH / g, hydroxyl value is 30 ~ 80mgK
It is advantageous to use OH / g, preferably 30 to 60 mg KOH / g. Tg of binder resin is DS
The endothermic peak in the C curve is preferably in the range of 50 to 65 ° C. If the Tg is lower than 50 ° C., the toner may be solidified during storage, and if the Tg is higher than 65 ° C., the low-temperature fixability may not be satisfactory. Particularly, in recent years, there is a tendency that a binder for low-temperature fixing is desired in order to keep power consumption low. Therefore, if storage stability can be ensured, Tg is preferably lower.

Regarding charging, it is desirable to select a binder resin which does not easily adsorb moisture in the air in order to minimize environmental fluctuations. For this reason, in the present invention, it is necessary to use a large amount of aromatic monomer in order to keep the water content low. When bisphenol PO or EO adduct is used as the alcohol and terephthalic acid or citric acid is used as the carboxylic acid, moisture in the air is less likely to be adsorbed, which is preferable. Using this aromatic material, acid value is 5mgK
OH / g or less and a hydroxyl value of 30 to 80 mgKOH / g can further prevent the adsorption of water, and
ppm or less is possible. When the content is 3000 ppm or less, the environmental stability is further improved.

Although the acid value is preferably as low as possible, it is difficult to synthesize an acid value of 1 or less from the viewpoint of polyester reaction.
OH / g. The hydroxyl value is also desirably suppressed to 80 mgKOH / g from the industrial limit of 30 mgKOH / g for the esterification reaction. The region of 30 mgKOH / g or less is an unconfirmed region, and the same as the acid value, 80 mgKOH / g or less, preferably 60 mgKOH / g or less is required to suppress the water content of the binder resin. By adjusting the acid value and the hydroxyl value to appropriate ranges, the water content becomes 3000p.
pm or less.

Here, the method for measuring the water content of the binder resin will be described as follows. First, add 200 resin
It is pulverized to not more than μm and stored for 24 hours in an environment of 30 ° C. and 60% RH. The water content of this resin is measured using a vaporizer of a Karl Fischer moisture titrator. In addition, in order to obtain a required amount of charge, the effect of reducing the charge control agent (inexpensive toner) is also provided.

The binder resin of the toner obtained as described above is mixed with a colorant and / or magnetic powder and, if necessary, a charge controlling agent and other additives, and is appropriately melt-mixed to form a toner for developing an electrostatic image. can do.

As the coloring agent, conventionally known coloring agents such as carbon black, iron oxide pigment, phthalocyanine blue, phthalocyanine green, rhodamine 6G cake, and watching red strontium can be used. The amount of the colorant contained in the toner is 1 to 60% by weight.
Is appropriately selected and used within the range described above.

Examples of the charge controlling agent include nigrosine dye, fatty acid-modified nigrosine dye, metal-containing nigrosine dye, metal-containing fatty acid-modified nigrosine dye, 3,5-di-tert-
A chromium complex of butylsalicylic acid or the like can be used, and is usually used in the toner in an amount of 0 to 20% by weight.

A wax having a melting point of 70 ° C. to 170 ° C. is used as a release agent. Specific examples of the release agent include:
Examples thereof include carnauba wax, montan wax, sasol wax, paraffin wax, low molecular weight polyethylene, low molecular weight polypropylene, and ethylene-vinyl acetate copolymer. These are added to the toner in the range of 1 to 10% by weight. The addition of wax gives mold releasability and certainly improves hot offset, but on the other hand, there is a problem in compatibility with the resin, and the developability deteriorates as the amount increases. In addition, since spent with a carrier also occurs, the charge amount becomes insufficient and the charge becomes unstable. For this reason, it is preferable that the amount of the wax is as small as possible. However, the releasability can be obtained without causing the occurrence of carrier spent or a shortage of charge. It was found that the wax in the toner became 2 μm or less by kneading with a high shearing energy during kneading with the particle size of the wax used being 100 μm or less. When the particle size is 2 μm or less, even if 10% is added to the toner, the above-mentioned side effect due to the wax does not occur, and the effect of the releasability can be obtained. The particle size is 2 μm
The following waxes were used by confirming the cross section of the toner with a TEM photograph.

As other additives, silica powder, hydrophobic silica powder, polyolefin, paraffin wax, fluorocarbon compound, fatty acid ester, partially saponified fatty acid ester, fatty acid metal salt and the like can be used. 0.1 to 5% by weight is used in the toner.

The toner of the present invention can be used for either a dry one-component developer or a two-component developer. As a magnetic material in the case of a one-component developer, alloys containing ferromagnetic elements such as ferrite, magnetite, etc., iron, cobalt, nickel, etc., or compounds containing no ferromagnetic elements, but appropriately heat-treated Alloys that have become ferromagnetic by doing so, for example, alloys of the type called Heusler alloys containing manganese and copper, such as manganese-copper-aluminum or manganese-copper-tin, or chromium dioxide. . The magnetic substance is usually uniformly dispersed in the binder resin in the form of a fine powder having an average particle diameter of 0.3 to 30 μm. The content of the magnetic particles is 20 to 70% by weight, preferably 40 to 70% by weight in the toner.
70% by weight is desirable. Conventionally, in the case of a magnetic material of 0.1 μm, it was not sufficiently dispersed and aggregated, but due to the high viscosity of the binder resin and high energy shearing during kneading, the dispersion of the magnetic material of 0.1 μm or less was reduced. It is now possible. Since the fine dispersion of the magnetic material became possible, the toner cleaning property was improved.

The toner in the two-component developer is composed of a colorant, a binder resin, and a charge control agent as main components, as is generally used.

The toner compositions according to the present invention are made by any of the well-known toner mixing and grinding methods. For example, all the components are mixed in a predetermined amount, mixed and crushed to thoroughly mix all the components, and then the resulting mixture is pulverized. In another known method of forming toner powders, the colorant, resin and solvent are ball milled and the toner formulation mixture is spray dried.

In order to use the toner composition according to the present invention by a cascade developing method, a magnetic brush developing method, an O-shell developing method, or the like, the composition has an average particle size expressed by weight percentage of about 30 μm or less. It is desirable that this average particle size be between about 4-20 μm for optimal results. For use in powder cloud development, particles having a particle size slightly smaller than 1 μm are desirable.

Cascade development, magnetic brush development, C
Coated and uncoated carriers, such as those used in shell development, are well known, but the carrier particles are brought into intimate contact with the toner powder such that the toner powder adheres to and surrounds the carrier particles. When
The carrier particles may be formed of any suitable material as long as the toner powder acquires a charge having a polarity opposite to that of the carrier particles. Accordingly, the toner compositions of the present invention can be used in combination with conventional carriers to develop electrostatic latent images on any suitable electrostatic latent image bearing surface, including conventional photoconductive surfaces. Is done.

(Toner Production Method)
As a method for obtaining a content of ２０20% by weight, there is a method of cutting molecules in the molecular region of the THF-insoluble portion by mechanical energy. This method uses a THF insoluble content of 10 to 40.
A binder resin of a polyester resin and a vinyl resin, which are contained by weight%, is kneaded while mixing carbon black, a charge control agent, and other additives, and applying mechanical shear energy.

In the case of kneading, first of all, after preliminarily mixing with a mixer such as a V blender and a Henschel mixer,
The mixture is generally kneaded at 100 to 200 ° C. using a pressure kneader, a Hanbury mixer, a single-screw or twin-screw continuous kneader, or the like. In the case of such kneading, there is an area where molecules are cut by mechanical shear energy. This is mainly governed by the viscosity during kneading. The viscosity is suitably 10 ⁴ to 10 ⁷ poise. When kneaded at a viscosity lower than this viscosity range, molecules are not easily cut, and THF insoluble components remain in the toner. Conversely, when kneaded with a high viscosity, in addition to being not dispersed with other materials, there are cases where the load on the machine is large and the machine is damaged. It is considered that the molecular cleavage is caused by the cleavage of a polymer having a network structure having a weight average molecular weight of about 1 × 10 ⁶ or more. Looking at the molecular weight distribution before and after kneading, the molecular weight range of about 1 × 10 ⁴ or less has not changed. Cleavage of this molecule is difficult to obtain synthetically.

As a toner characteristic, a molecular weight in this range is effective for hot offset and filming. However, on the other hand, it works in a disadvantageous way to grindability and fixability,
In order to improve the pulverizability and fixing property, it is desirable to define the molecular weight distribution after kneading. That is, the mixture is kneaded within the above-mentioned viscosity range, has a main peak in the region of 2,000 to 10,000 in GPC, and has a molecular weight (Mw) of 10,000 or less in the range of 50 to 10,000.
By containing 70%, the fixability and the pulverizability are improved. In particular, a component having a low molecular weight (Mw) is preferable, and a component having a main peak at Mw of 2,000 to 10,000, preferably 2,000 to 4,000 is preferable.

If the vinyl resin accounts for more than 30% by weight of the binder resin in the present invention, the resistance to PVC is lowered and the fixability is also deteriorated. For environmental stability, vinyl resin, especially styrene, mainly acrylic, methacrylic,
Alternatively, a copolymer with butadiene increases hydrophobicity and is more environmentally stable than polyester alone. The vinyl resin is preferably used in an amount of 30% by weight or less in consideration of PVC resistance, charging environment stability, and fixability.

The viscosity of 1 × 10 ⁴ to 1 × 10 ⁷ poise during kneading is suitable for dispersing the wax component to 2 μm or less.
Resin that can be used for toner other than vinyl resin such as epoxy resin and phenol resin
Can also be used at 30% by weight or less.

Next, a method for obtaining a toner in which a polyolefin is finely dispersed at 2 μm or less will be described. The dispersibility of the polyolefin wax becomes very good due to the presence of the microgel component in the binder resin. This is because the microgel component has a great influence on the rheological properties. That is, a high-molecular polymer is a substance that exhibits typical viscoelastic behavior. It has a branched structure formed by cutting a cross-linked resin molecule of polyester or vinyl resin, and has a large storage modulus G 'during kneading. The temperature at the time of kneading the toner is generally in the range of 100 to 200 ° C., but even in this range, the polymer having a branched structure does not flow and has an elastic modulus of at least about 10 ³ dyne / cm ^2. Is known to be maintained (Oka
Koten, "Introduction to Rheology," p. 83, published by the Industrial Research Council.)
The elastic modulus relates to the cohesive force of the substance, and the polyolefin wax is kneaded in a state of being subjected to the cohesive force from the entire toner phase including the microgel component, so that strong shear is applied and the dispersibility is improved.

On the other hand, when a system containing no subpeak, that is, a linear polymer is used as the binder resin,
It is known that under general kneading conditions, the resin flows and the elastic modulus goes to zero. Until now, several inventions using polyolefin waxes have been proposed, but in most cases, they have poor compatibility with the binder resin and result in poor dispersion. However, since a system in which a polyester resin and a vinyl resin are blended and a microgel component is contained exhibits viscoelastic behavior suitable for kneading, the polyolefin wax is finely dispersed at 2 μm or less.

By the way, a two-component developer comprising a mixture of carrier particles and toner particles has been well known, but the carrier used in the two-component developer always has the desired polarity for the toner particles during long-term use. And triboelectrically charge to a sufficient charge amount. In order to obtain a more stable charge and a developer free of carrier contamination (WAX, additive) in the present toner, mixing with a carrier coated with a silicone resin is suitable. In particular, since the charging stability of the toner is indispensable for the durability quality of the developer, mixing with the carrier coated with the silicone resin is a great effect. As the silicone resin used for the silicone resin film carrier, KR271KR225 manufactured by Shin-Etsu Chemical Co., Ltd. is commercially available. Sand, cobalt, iron, ferrite, and magnetite having an average particle size of 50 to 200 microns are used as the carrier core material. As a method of forming a silicone resin film, there is a spray method or the like.

[0060]

Next, the present invention will be described more specifically with reference to examples. Parts here are by weight.

Table 1 shows the compositions of the polyester resins used in the examples and comparative examples and their physical properties.

[0062]

[Table 1]

(Abbreviations of raw materials shown in Table 1) (1) Glycol A: polyoxypropylene (2, 2)
-2,2-bis (4-hydroxyphenyl) propane (hydroxyl value 315) (2) Glycol B: polyoxyethylene (2,3)-
2,2-bis (4-hydroxyphenyl) propane (hydroxyl value 340) (3) glycol C: poly (oxyethylene-propylene) -bis- (4-hydroxyphenyl) methane (hydroxyl value 320) (4) glycol D : Polyoxypropylene (3,1)
-2,2-bis (4-hydroxyphenyl) propane (hydroxyl value: 275) (5) EG: ethylene glycol (6) NPG: neopentyl glycol (7) TPA: terephthalic acid (8) IPA: isophthalic acid (9) FA: fumaric acid (10) AA: adipic acid (11) DMT: dimethyl terephthalate (12) DSA: dodecenyl succinic anhydride (13) TMA: trimellitic anhydride

(Method for Measuring Physical Properties of Polyester Resin) Acid value and hydroxyl value According to the method specified in JIS K0070. However, when the sample does not dissolve, a solvent such as dioxane or tetrahydrofuran is used as the solvent. 2. Glass transition temperature (Tg) Method specified in ASTM D3418-82 (DSC method)
by.

Examples 1-4 and Comparative Examples 1-4 3000 g of resin under the conditions of Table 2, 20 parts of carbon black (# 40 manufactured by Mitsubishi Chemical Corporation), oil black BY
250 g (manufactured by Orient Chemical Co., Ltd.) was heated and melt-kneaded with two rolls. The kneading conditions are shown in Table 2. Each evaluation was performed by the following method. Grindability during toner production The kneaded toner was roughly pulverized by a hammer mill and finely pulverized by a jet air mill. At this time, the supply amount required to obtain an average particle size of 10 μm was measured and used as an index of pulverizability. The discharge air pressure was 5.0 kg / cm ² . Image evaluation method 50 parts of toner having a particle size of 10 to 11 μm and a carrier coated with silicone resin (silicone resin: K manufactured by Shin-Etsu Chemical Co., Ltd.)
R250, 950 parts of a core carrier (100 μm) and sufficiently shaken to obtain a developer. Using this developer, image evaluation is performed using a high-speed copying machine (FT8200 manufactured by Ricoh Company). Environmental stability High temperature, high humidity (30 ° C, 90%) charging and low temperature, low humidity (10
(30 ° C., 30%).

Synthesis of vinyl resin (vinyl resin A-1,
Synthesis of A-2) 3 equipped with a cooling pipe, a stirrer, a gas introduction pipe, and a thermometer
Charge ion-exchanged water and monomer into a liter flask. Examples of the formulation are shown in Table 2 as A-1 and A-2. The liquid was heated with stirring, and the temperature was raised to a prescribed reaction temperature, and the reaction time was 12 hours in all cases. The obtained polymer was washed with water and dried at a normal temperature of 10 Torr to obtain a powdery powder having a volatile content of 1% or less.

[0067]

[Table 2]

From the results shown in Table 3, compared to Examples 1 to 4, toners in which the temperature of the flow tester is out of the range are toners having poor low-temperature fixability or hot offset balance. Further, as compared with Examples 1 to 4, Comparative Example 3 having a large amount of the microgel component and Comparative Example 4 in which the THF-insoluble portion remains had poor low-temperature fixability and pulverizability. Therefore, it can be seen that Examples 1 to 4 have a good balance of fixing property, hot offset property, pulverizability, and charging environment stability.

[0069]

[Table 3]

Examples 5 to 8 and Comparative Examples 5 to 8 In the same manner as in Examples 1 to 4 and Comparative Examples 1 to 4, toners were prepared using Resins I to VII. However, wax in it
Added. As a comparative example, the dispersed particle size of the wax is 2 μm.
Were evaluated. Table 4 shows the results.

[0071]

[Table 4]

Example 9 (Example of developer) A developer was prepared for the toners of Examples 1 and 2 in Table 3 using a silicone resin-coated iron powder and a non-coated iron powder as a carrier. Using the developer, a 100,000 copy test was performed with an electrophotographic copying machine (FT8200) manufactured by Ricoh Company. As a result, the developer using the carrier coated with the silicone resin had a clear image even with 100,000 copies and a change in the charge amount of 10 μc / g. On the other hand, the image density of the non-coated carrier was reduced on 100,000 sheets, and the decrease in the charge amount was as large as 19 μc / g.

Example 10 and Comparative Example 9 1500 g of a resin composed of polyester resins I and IV; 250 g of oil black BY (manufactured by Orient Chemical Co., Ltd.) and 1500 g of a magnetic material (magnetite) were heated and melt-kneaded with two rolls. Table 5 summarizes the kneading conditions and toner evaluation.
Shown in In addition, cleaning performance and image density were added to the evaluation. R-10 M-10 was used as an evaluation machine.
From the results shown in Table 5, it was found that Comparative Example 9 was a toner having a large particle diameter of the magnetic material, while Example 10 was a toner having a good balance such as position fixing, hot offset, and cleaning properties.

[0074]

[Table 5]

[0075]

(1) The toner having the temperature range of the flotester described in claim 1 can provide a toner having a good balance of low-temperature fixability, hot offset and pulverizability. (2) By using the binder resin described in the second aspect, it is possible to obtain a toner having a wide range of fixing temperature with improved low-temperature fixing property and hot offset property. (3) By using the binder resin according to the third aspect, a toner having good low-temperature fixability can be obtained. (4) The toner satisfying claim 4 can provide a toner having excellent environmental stability. (5) The toner satisfying claim 5 can provide a toner having excellent environmental stability. (6) The hot offset can be further improved by containing the wax of claim 6 and making the dispersed particle diameter of the wax 2 μm or less. (7) The toner in which the magnetic particles are contained in the toner and the particle diameter of the particles is 0.1 μm or less can improve the cleaning property. (8) A developer satisfying claim 8 can provide a developer with less charge deterioration even in durability quality.

[Brief description of the drawings]

FIGS. 1A and 1B are diagrams for calculating a flow tester value of a toner according to the present invention.

Claims (8)

[Claims] 1. An electrostatic image developing toner comprising a binder resin in which a colorant is dispersed, wherein the softening point, outflow start temperature, F1 / 2 temperature and outflow end temperature measured by an elevated flow tester are as follows: A toner for developing an electrostatic image, wherein the toner is within a range. Softening point: 70-85 ° C, outflow starting temperature: 110-125
° C, F1 / 2 temperature: 145-160 ° C, outflow end temperature:
150-180 ° C. 2. The binder resin has no tetrahydrofuran dissolved component and has a molecular weight of 1 × 10 ⁷ or more and a component of 5 to 20%.
The toner for developing an electrostatic image according to claim 1, wherein the toner is contained. 3. The binder resin is prepared by gel permeation chromatography (G
PC) in the molecular weight distribution from 2000 to 1000
0 having a main peak and a molecular weight of 1000
The value of 0 or less is 50 to 70%.
Or the toner for developing an electrostatic image according to 2. 4. The electrostatic image developing toner according to claim 1, wherein the binder resin is a polyester resin or a polyester resin blended with a vinyl resin. 5. The binder resin having a water content of 30.degree.
The toner for developing an electrostatic charge image according to any one of claims 1 to 4, wherein the toner content is 5000 ppm or less in% (humidity control for 24 hours). 6. The composition according to claim 1, further comprising a wax, wherein the dispersed particle diameter of the wax is 2 μm or less.
6. The toner for developing an electrostatic image according to any one of 5. 7. A magnetic one-component toner, wherein the toner for developing an electrostatic image according to claim 1 contains magnetic particles having a particle diameter of 0.1 μm or less. 8. An electrophotographic developer comprising a mixture of carrier particles surface-coated with a silicone resin and the toner according to any one of claims 1 to 6.