JP3262504B2 - Negatively chargeable toner for developing electrostatic images - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a negatively chargeable toner for developing an electrostatic image used in an image forming method such as an electrophotographic method, an electrostatic recording method, and an electrostatic printing method.

[0002]

2. Description of the Related Art Conventionally, electrophotography has been disclosed in U.S. Pat. No. 2,297,691, Japanese Patent Publication No. 42-23910.
Numerous methods are known as described in Japanese Patent Application Laid-Open Publication No. Hei. Generally, a photoconductive substance is used to form an electrostatic charge image on a photoreceptor by various means, and then the electrostatic charge image is developed using a toner, and if necessary, a toner image is formed on a transfer material such as paper. After transferring
The toner image is fixed by heating, pressure, heating and pressurizing, or solvent vapor to obtain a toner image.

[0003] As a method of fixing the toner image to a sheet such as paper, which is the final step, the most common fixing method at present is a pressure heating method using a heating roller.

In this method, a toner image is formed by allowing a toner image surface of a sheet to be fixed to pass through the sheet while the toner image is brought into contact with the surface of a heating roller having a surface formed of a material having a releasing property to the toner. Is to fix the image.

According to this method, since the surface of the heating roller and the toner image on the sheet to be fixed come into contact with each other under pressure, the thermal efficiency at the time of fusing the toner image onto the sheet to be fixed is extremely good. Fixing can be performed quickly.

However, in this method, since the surface of the heating roller and the toner image come into contact with each other under pressure in a molten state, a part of the toner image adheres to the surface of the fixing roller.
There is a problem that the sheet is transferred and re-transferred to the next sheet to be fixed, causing an offset phenomenon, thereby soiling the sheet to be fixed.
Therefore, it is necessary for the toner to have excellent low-temperature fixability and high-temperature offset resistance.

Until now, various toners have been proposed to achieve both low-temperature fixability and high-temperature offset resistance. For example, JP-A-63-225244-63
JP-A-225246 discloses a toner containing two types of non-linear polyesters for the purpose of improving low-temperature fixability, high-temperature offset resistance, and blocking resistance. However, as a toner having a wide fixing temperature range applicable from low speed to high speed and excellent in anti-offset property, there still remains a problem to be improved in addition to image characteristics described later.

Further, JP-A-3-188468 discloses that a polyester resin as a binder in toner particles has the following conditions (A) to (C): (A) the polyester resin has an acid value of Av and a hydroxyl value of OH
v, 20 to 35 (KOHmg / g),
Av / OHv = 1.0-1.5,
(B) The tetrahydrofuran-insoluble content is 10% or less, and (C) the weight average molecular weight Mw and the number average molecular weight Mn in the molecular weight distribution by gel permeation chromatography (GPC) of the tetrahydrofuran soluble component.
Is Mw / Mn ≧ 10, and the number average molecular weight is 3,
Peak in the region of 000-8,000 (low molecular side peak)
Having at least one number average molecular weight of 100,000 to
It has one peak or shoulder (polymer-side peak) in the region of 600,000, and the polymer-side peak region is 5 to 15
%, A toner that satisfies the following condition is proposed. However, the polyester resin specifically described in Examples of JP-A-3-188468 has a small weight average molecular weight of 40,000 to 80,000, and Mw / Mn
Is also as small as 13.3 to 16.6, further improvement of low-temperature fixability and high-temperature offset resistance is required.

In recent years, it has been desired to improve the quality of copy images by making toner finer. However, various problems occur even though the resolution and sharpness of an image can be increased by making the toner finer.

First, the fixability of the halftone portion deteriorates due to the fine particles of the toner. This is because the amount of toner applied to the halftone portion is small, the amount of heat transferred from the heating roller to the toner transferred to the concave portion of the fixing sheet is extremely small, and the fixing pressure is also suppressed by the convex portion of the fixing sheet. Because it gets worse. Since the toner transferred to the convex portion of the sheet to be fixed in the halftone portion has a small toner layer thickness, the shear force applied to each toner particle is much larger than that of the solid black portion having a large toner layer thickness. Therefore, an offset phenomenon occurs and a low-quality copy image is obtained.

Further, there is a problem of fog. By reducing the toner particle size, the surface area per unit weight of the toner particles increases, and therefore, the width of the charge amount distribution of the toner increases, and fogging easily occurs.

By increasing the surface area per unit weight of the toner particles, the charging characteristics of the toner become more susceptible to the influence of the environment.

There is a need for a toner that better solves the various problems described above.

[0014]

SUMMARY OF THE INVENTION An object of the present invention is to provide a negatively chargeable toner for developing an electrostatic image, which solves the above-mentioned problems.

It is a further object of the present invention to provide a negative charge for developing an electrostatic image, which has excellent low-temperature fixability and high-temperature offset resistance.
The present invention is to provide a neutral toner.

A further object of the present invention is to provide a negative band for developing an electrostatic image which exhibits excellent fixability even in a halftone image area.
An object of the present invention is to provide an electrically conductive toner.

It is a further object of the present invention to provide a negatively chargeable toner for developing an electrostatic image having a small particle size and having excellent low-temperature fixability and high-temperature offset resistance.

It is a further object of the present invention to provide a negatively chargeable toner for developing electrostatic images, which is excellent in environmental stability.

[0019]

That is, the present invention relates to a negatively chargeable toner for developing electrostatic images containing at least a binder resin, a colorant and a charge control agent, wherein the binder resin contains a polyester resin. The polyester resin has an acid value of 15 to 40 and a hydroxyl value of 45 or less. The soluble matter in tetrahydrofuran (THF) of the toner is determined by gel permeation chromatography (GPC) using a weight average molecular weight (Mw). ) Is 100,000 or more, the ratio (Mw / Mn) of the number average molecular weight (Mn) to the weight average molecular weight (Mw) is 35 or more, and the content of the component in the low molecular weight region having a molecular weight of 150,000 or less is 70 to 94%, and the content of components in the middle molecular weight region of 150,000 to 500,000 is 1
Was 10%, the content of components having a molecular weight of 500,000 or more high molecular weight region is 5 to 25%, and rather a multi than of component is a medium molecular weight region of the high molecular weight region, a charge control agent an azo
For developing electrostatic images characterized by being iron-based complex compounds
The present invention relates to a negatively chargeable toner.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION In the toner of the present invention, the molecular weight distribution is optimized so as to satisfy the following conditions in gel permeation chromatography of a soluble portion of tetrahydrofuran (THF) of a polyester resin in the toner. As a result, the fixing area was expanded.

(A) the weight average molecular weight (Mw) is 100,000 or more, more preferably 200,000 to 3,000,000; (b) the ratio (Mw / Mn) of the number average molecular weight (Mn) to the weight average molecular weight (Mw) is (C) 70 to 94% of the content of the component in the low molecular weight region having a molecular weight of 150,000 or less; (d) content of the component in the middle molecular weight region of 150,000 to 500,000. (E) the content of the component in the high molecular weight region having a molecular weight of 500,000 or more is 5 to 25%; (f) the component in the high molecular weight region contains more than the component in the medium molecular weight region, more preferably The components in the high molecular weight region are 1 to 20% more than the components in the medium molecular weight region.

If the above conditions are not satisfied, one or both of the low-temperature fixing property and the high-temperature offset resistance will be impaired. If the proportion of the low molecular weight region is small, the low-temperature fixability is impaired. If the proportion of the high molecular weight region is small, or if Mw is smaller than 100,000, the high-temperature offset resistance is impaired. If the ratio of the medium molecular weight region increases or Mw / Mn becomes smaller than 35, both the low-temperature fixing property and the high-temperature offset resistance are impaired. Since the content of the THF-insoluble component of the polyester resin in the toner also inhibits the low-temperature fixability, the THF-insoluble component of the resin component is preferably 10% by weight or less, and more preferably contains no THF-insoluble content or 5% or less. It is better to

As a method for satisfying the above conditions for the molecular weight distribution of the polyester resin in the toner, a polyester resin containing a THF-insoluble component is used as a raw material resin, and the THF-insoluble component is removed in a kneading step in the production of the toner. It is preferred to make the high molecular weight component by cutting with heat and shear. However, at this time, if a material having a crosslinking property is included in the toner raw material, a crosslinking reaction occurs between the polyester resin and the crosslinking component during kneading,
Since the high molecular weight component and the medium molecular weight component increase, the low-temperature fixability decreases. Since a chromium complex compound generally used as a charge control agent for imparting a negative charge to a toner is liable to cause cross-linking during kneading described above, it is preferable to use an organic metal compound other than chromium. In particular, since the azo-based iron complex does not show a crosslinking property with the polyester resin at the time of kneading, optimization of the molecular weight distribution can be achieved.

The polyester resin in the toner has an acid value of 1
Those having a hydroxyl value of 5 to 40 and a hydroxyl value of 45 or less are used. When the acid value is less than 15, the image density is liable to decrease due to continuous copying under low humidity, and fogging tends to occur. When the acid value exceeds 40, the image density tends to decrease under high humidity, probably because the charge relaxing action by the acid group is too large. If the hydroxyl value exceeds 45, the image density tends to decrease under high humidity. The hydroxyl value is more preferably 5 to 42.

The preferred composition of the polyester resin used in the present invention will be described below.

The polyester resin used in the present invention comprises:
40-60 mol% of all components are alcohol components,
60 to 40 mol% is an acid component.

Examples of the alcohol component include ethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, diethylene glycol, triethylene glycol,
1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, 2-ethyl-1,3-hexanediol, hydrogenated bisphenol A, and a bisphenol derivative represented by the formula (A);

[0028]

[Outside 5] [Wherein, R is an ethylene or propylene group, and x,
y is an integer of 1 or more, and the average value of x + y is 2
To 10].

A diol of the formula (B);

[0030]

[Outside 6] And diols such as

Examples of the divalent carboxylic acid containing 50 ml% or more of the total acid component include benzenedicarboxylic acids such as phthalic acid, terephthalic acid, isophthalic acid and phthalic anhydride or anhydrides thereof; succinic acid, adipic acid, sebacic acid, Alkyl dicarboxylic acids such as azelaic acid or anhydrides thereof, succinic acids or anhydrides thereof substituted with an alkyl or alkenyl group having 6 to 18 carbon atoms; unsaturated dicarboxylic acids such as fumaric acid, maleic acid, citraconic acid, itaconic acid; An acid or its anhydride is mentioned.

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 anhydrides thereof. Can be

The alcohol component of the polyester resin particularly preferred in the practice of the present invention is a bisphenol derivative represented by the formula (A), and the acid component is phthalic acid, terephthalic acid, isophthalic acid or its anhydride, or succinic acid. , N-dodecenyl succinic acid or anhydride,
Examples thereof include dicarboxylic acids such as fumaric acid, maleic acid, and maleic anhydride or anhydrides thereof. Preferable examples of the crosslinking component include trimellitic anhydride, benzophenonetetracarboxylic acid, pentaerythritol, and oxyalkylene ether of a novolak type phenol resin.

The glass transition temperature (T
g) is 40 to 80 ° C, preferably 45 to 75 ° C.
As described above, in the kneading process during toner production, TH
The polyester resin contains 5 to 30% by weight, preferably 10 to 25% by weight of a THF-insoluble component which is an F-soluble high molecular weight component.
It is preferred to include.

In order to suitably generate the molecular weight distribution defined in the present invention after the toner particles are formed, a first polyester resin containing a large amount of low molecular weight components not containing a THF insoluble component and a high polyester containing a THF insoluble component are used. Second containing a high molecular weight component
It is preferable to use a mixture of the polyester resin and the polyester resin because the molecular weight distribution can be easily adjusted.

The first polyester resin has a THF insoluble content of 0 wt% and a THF soluble content of 70 wt%.
It is preferably from 100,000 to 100,000, and Mn is preferably from 2000 to 10,000.

The second polyester resin has a THF-insoluble content of 10 to 50% by weight, and a THF-soluble content of M
w is 30,000 to 500,000 and Mn is 2500 to 15000
It is preferable that

The first polyester resin and the second polyester resin are mixed in a ratio of 1: 9 to 9: 1, more preferably 2: 8.
It is preferable to use the raw material of the binder resin before the toner is formed by mixing at a weight ratio of 8: 2.

The azo iron complex compound used in the present invention is
It preferably has a structure represented by the following formula.

[0040]

[Outside 7] [Wherein X ₁ and X ₂ represent a hydrogen atom, a lower alkyl group,
Represents a lower alkoxy group, a nitro group or a halogen atom, and X ₁ and X ₂ may be the same or different;
m and m 'represents an integer of 1 to 3, R ₁ and R ₃ is a hydrogen atom, an alkyl of C ₁ ~ _18, alkenyl, sulfonamide, mesyl, sulfonic acid, carboxy ester, hydroxy, alkoxy of C ₁ ~ ₁₈ represents acetylamino, benzoylamino group or a halogen atom, R ₁ and R
₃ may be the same or different and n and n '
Represents an integer of 1 to 3, R ₂ and R ₄ represent a hydrogen atom or a nitro group, and A ⁺ represents a hydrogen ion, a sodium ion, a potassium ion or an ammonium ion].

The azo iron complex compound is used as a negative charge control agent. The azo-based iron complex compound can be synthesized by known means.

These negative charge control agents may be used alone or in combination of two or more.

Representative specific examples of the azo-based iron complex compound of the above general formula include the following compounds.

[0044]

[Outside 8]

[0045]

[Outside 9]

[0046]

[Outside 10]

In the toner for developing an electrostatic image of the present invention, 0.1 to 10 parts by weight, preferably 0.1 to 5 parts by weight, of the azo iron complex compound of the above general formula is used per 100 parts by weight of the binder resin. Is preferred.

When the toner of the present invention is used as a magnetic toner, the magnetic material contained in the magnetic toner includes iron oxides such as magnetite, maghemareite and ferrite, and iron oxides containing other metal oxides; Fe, Co, Ni Or a metal such as Al, Co, C
u, Pb, Mg, Ni, Sn, Zn, Sb, Be, B
Examples include alloys with metals such as i, Cd, Ca, Mn, Se, Ti, W, and V, and mixtures thereof.

As a magnetic material, conventionally, triiron tetroxide (F
e ₃ O ₄ ), iron sesquioxide (γ-Fe ₂ O ₃ ), zinc iron oxide (ZnFe ₂ O ₄ ), yttrium iron oxide (Y ₃ Fe
₅ O ₁₂ ), cadmium iron oxide (CdFe ₂ O ₄ ), gadolinium iron oxide (Gd ₃ Fe ₅ -O ₁₂ ), copper iron oxide (C
uFe ₂ O ₄ ), lead iron oxide (PbFe ₁₂ —O ₁₉ ), nickel iron oxide (NiFe ₂ O ₄ ), iron neodymium oxide (Nd
Fe ₂ O ₃ ), barium iron oxide (BaFe ₁₂ O ₁₉ ), magnesium iron oxide (MgFe ₂ O ₄ ), iron manganese oxide (MnFe ₂ O ₄ ), lanthanum iron oxide (LaFeO)
₃ ), iron powder (Fe), cobalt powder (Co), nickel powder (Ni) and the like are known. According to the present invention, the above-mentioned magnetic materials are selectively used alone or in combination of two or more. Particularly suitable magnetic materials for the purposes of the present invention are fine powders of triiron tetroxide or γ-iron sesquioxide.

These magnetic materials have an average particle size of 0.1 to 2 μm.
m (more preferably 0.1 to 0.5 μm), 79
When the magnetic properties at 5.8 kA / m applied are 1.5 kA / coercive force.
m to 12 kA / m, saturation magnetization 50 to ²⁰⁰ Am ² / kg
(Preferably 50 to 100 Am ² / kg), remanent magnetization 2
It is preferred for ~20Am ² / kg.

The magnetic material 1 was added to 100 parts by weight of the binder resin.
It is preferable to use 0 to 200 parts by weight, preferably 20 to 150 parts by weight.

As a coloring agent, carbon black, titanium white, and other pigments and / or dyes can be used. For example, when the toner of the present invention is used as a color toner, C.I. I. Direct Red 1, C.I. I. Direct Red 4, C.I. I. Acid Red 1, C.I. I. Basic Red 1, C.I.
I. Modant Red 30, C.I. I. Direct Blue 1, C.I. I. Direct Blue 2, C.I. I. Acid Blue 9, C.I. I. Acid Blue 15, C.I. I. Basic Blue 3, C.I. I. Basic Blue 5, C.I. I.
Modant Blue 7, C.I. I. Direct Green 6,
C. I. Basic Green 4, C.I. I. Basic Green 6 and the like. Examples of pigments include: graphite, cadmium yellow, mineral fast yellow, navel yellow, naphthol yellow S, Hansa yellow G, permanent yellow NCG, tartrazine lake, red-mouthed graphite, molybdenum orange, permanent orange, G
TR, pyrazolone orange, benzidine orange G, cadmium red, permanent red 4R, watching red calcium salt, eosin lake, brilliant carmine 3B, manganese purple, fast violet B,
Methyl Violet Lake, Navy Blue, Cobalt Blue, Alkaline Blue Lake, Victoria Blue Lake, Phthalocyanine Blue, Fast Sky Blue, Indanthrene Blue BC, Chrome Green, Pigment Green B, Malachite Green Lake, Final Yellow Green G, and the like.

When the toner of the present invention is used as a two-component full-color image forming toner, the following may be mentioned. Examples of the magenta coloring pigment include C.I. I. Pigment Red 1,2,3,4,5,6,7,8,9,1
0, 11, 12, 13, 14, 15, 16, 17, 1
8, 19, 21, 22, 23, 30, 31, 32, 3
7, 38, 39, 40, 41, 48, 49, 50, 5
1,52,53,54,55,57,58,60,6
3,64,68,81,83,87,88,89,9
0, 112, 114, 122, 123, 163, 20
2,206,207,209, C.I. I. Pigment Violet 19, C.I. I. Butt Red 1,2,10,1
3, 15, 23, 29, 35 and the like.

Although the pigment may be used alone, it is more preferable to use the dye and the pigment together to improve the sharpness from the viewpoint of the image quality of a full-color image. Magenta dyes include C.I. I. Solvent red 1,3,8,23,
24, 25, 27, 30, 49, 81, 82, 83, 8
4,100,109,121, C.I. I. Disperse Red 9, C.I. I. Solvent Violet 8,13,1
4, 21, 27, C.I. I. Disperse Violet 1
Oil-soluble dyes such as C.I. I. Basic Red 1, 2,
9,12,13,14,15,17,18,22,2
3,24,27,29,32,34,35,36,3
7, 38, 39, 40, C.I. I. Basic violet 1,3,7,10,14,15,21,25,26,
And basic dyes such as 27 and 28.

Other coloring pigments include cyan coloring pigments such as C.I. I. Pigment Blue 2, 3, 15, 1
6, 17, C.I. I. Bat Blue 6, C.I. I. Acid Blue 45 or a copper phthalocyanine pigment in which a phthalocyanine skeleton having a structure represented by the following formula is substituted with 1 to 5 phthalimidomethyl groups.

[0056]

[Outside 11]

As the yellow coloring pigment, C.I. I. Pigment Yellow 1, 2, 3, 4, 5, 6, 7, 10, 1
1,12,13,14,15,16,17,23,6
5, 73, 83, C.I. I. Bat Yellow 1,3,20
And the like.

The coloring agent is based on 100 parts by weight of the binder resin.
0.1 to 60 parts by weight, preferably 0.5 to 50 parts by weight.

In the present invention, one or more release agents may be contained in the toner particles, if necessary.

The following are examples of the release agent used in the present invention. Low molecular weight polyethylene, low molecular weight polypropylene, microcrystalline wax, aliphatic hydrocarbon wax such as paraffin wax, aliphatic hydrocarbon wax oxide such as oxidized polyethylene wax, or block copolymer thereof; carnauba wax; Examples thereof include waxes mainly containing a fatty acid ester such as sasol wax and montanic acid ester wax, and those obtained by partially or entirely deoxidizing a fatty acid ester composition such as deoxidized carnauba wax. further,
Saturated linear fatty acids such as palmitic acid, stearic acid, montanic acid; unsaturated fatty acids such as brassic acid, eleostearic acid, and vinaric acid; stearyl alcohol, aralkyl alcohol, behenyl alcohol, carnaubyl alcohol, seryl alcohol, meri Saturated alcohols such as silalcohol; polyhydric alcohols such as sorbitol; fatty acid amides such as linoleamide, oleamide, lauric amide, methylenebisstearic amide, ethylenebiscapramide, ethylenebislauric amide, hexamethylene Saturated fatty acid bisamides such as bisstearic acid amide; ethylene bisoleic acid amide, hexamethylene bisoleic acid amide, N, N'-dioleyl adipamide, N,
Unsaturated fatty acid amides such as N'-dioleyl sebacic amide; m-xylene bissterinamide, N, N '
-Aromatic bisamides such as distearylisophthalamide; fatty acid metal salts such as calcium stearate, calcium laurate, zinc stearate and magnesium stearate (commonly referred to as metal soaps); Waxes produced by graft polymerization of vinyl monomers such as styrene and acrylic acid; partially esterified products of fatty acids and polyhydric alcohols such as behenic acid monoglyceride; methyl ester compounds having a hydroxyl group obtained by hydrogenating vegetable oils and fats And the like.

As the wax particularly preferably used in the present invention, an aliphatic hydrocarbon wax is exemplified. For example, a low molecular weight alkylene polymer obtained by radical polymerization of alkylene under high pressure or a Ziegler catalyst under low pressure; an alkylene polymer obtained by thermally decomposing a high molecular weight alkylene polymer; Preferred is a synthetic hydrocarbon wax obtained from a hydrocarbon distillation residue obtained by the method or by hydrogenating them. Further, those obtained by separating a hydrocarbon wax by use of a press sweating method, a solvent method, vacuum distillation or a separation crystallization method are more preferably used.
Hydrocarbons as bases are made of metal oxide catalysts (often 2
(E.g., a hydrocarbon compound synthesized by the reaction of carbon monoxide and hydrogen using a multi-component system of at least one kind), such as a hydrocarbon compound synthesized by the Zintall Hourly report, a hydrocoll method (using a fluidized catalyst bed); a waxy hydrocarbon Hydrocarbons having a carbon number of up to about several hundreds obtained by the Aggé method (using a fixed catalyst bed) in which a large amount of carbon is obtained; and hydrocarbons obtained by polymerizing an alkylene such as ethylene with a Ziegler catalyst.
These are preferable because they are linear hydrocarbons having a small number of branches and a small amount and having a long saturation. Particularly, a wax synthesized by a method not based on the polymerization of alkylene is preferable in view of its molecular weight distribution.

In the molecular weight distribution of the wax, the molecular weight is 400
It is preferable that the main peak exists in the region of ２2400, preferably 450-2000, particularly preferably 500-1600. By having such a molecular weight distribution, favorable thermal characteristics can be imparted to the toner.

The release agent is used in an amount of 0.1 to 20 parts by weight, preferably 0.5 to 10 parts by weight, per 100 parts by weight of the binder resin.

The release agent is usually prepared by dissolving the resin in a solvent, increasing the temperature of the resin solution, and mixing while stirring.
It is contained in the binder resin by a method of mixing at the time of kneading.

Examples of the negatively chargeable fluidity improver used in the toner of the present invention include those capable of improving the fluidity of the toner by externally adding to the toner particles. For example, fluorine-based resin powders such as vinylidene fluoride fine powder and polytetrafluoroethylene fine powder; fine powder silica such as wet-process silica and dry-process silica; silane coupling agents, titanium coupling agents, silicon Examples include silica treated with a surface treatment with oil or the like.

Preferred fluidity improvers are fine powders produced by the vapor phase oxidation of silicon halides, and are referred to as dry silica or fumed silica. For example, it utilizes the thermal decomposition oxidation reaction of silicon tetrachloride gas in oxygen and hydrogen, and the basic reaction formula is as follows.

SiCl ₂ + 2H ₂ + O ₂ → SiO ₂ + 4HCl

In this production process, it is possible to obtain a composite fine powder of silica and another metal oxide by using another metal halide such as aluminum chloride or titanium chloride together with the silicon halide. Include. The particle size is preferably in the range of 0.001 to 2 μm as an average primary particle size, and particularly preferably, fine silica powder in the range of 0.002 to 0.2 μm is used. .

Commercially available silica fine powder produced by the vapor phase oxidation of a silicon halide is, for example, one commercially available under the following trade names.

AEROSIL (Aerosil Japan) 130 200 300 380 TT600 MOX170 MOX80 COK84 Ca-O-SiL (CABOT Co.) M-5 MS-7 MS-75 HS-5 EH-5 Wacker HDK N20 V15 WAC -CHEMIE GMBH) N20E T30 T40 DC Fine Silica (Dow Corning Co.) Fransol (Fransil)

Further, it is more preferable to use a treated silica fine powder obtained by subjecting a silica fine powder produced by vapor phase oxidation of the silicon halide compound to a hydrophobic treatment. It is particularly preferable that the treated silica fine powder is obtained by treating the silica fine powder such that the degree of hydrophobicity measured by a methanol titration test shows a value in the range of 30 to 80.

The hydrophobizing method is applied by chemically treating with an organosilicon compound which reacts with or physically adsorbs silica fine powder. The preferred method is
The silica fine powder produced by the vapor phase oxidation of a silicon halide is treated with an organosilicon compound.

Examples of the organosilicon compound include hexamethyldisilazane, trimethylsilane, trimethylchlorosilane, trimethylethoxysilane, dimethyldichlorosilane, methyltrichlorosilane, allyldimethylchlorosilane, allylphenyldichlorosilane, benzyldimethylchlorosilane, Bromomethyldimethylchlorosilane,
α-chloroethyltrichlorosilane, β-chloroethyltrichlorosilane, chloromethyldimethylchlorosilane, triorganosilylmercaptan, trimethylsilylmercaptan, triorganosilyl acrylate, vinyldimethylacetoxysilane, dimethylethoxysilane, dimethyldimethoxysilane, diphenyldiethoxysilane , Hexamethyldisiloxane, 1,3-divinyltetramethyldisiloxane, 1,3-diphenyltetramethyldisiloxane and 2 to 12 siloxane units per molecule, each having one to each of the terminal units. Examples include dimethylpolysiloxane containing a hydroxyl group bonded to Si. These are used alone or as a mixture of two or more.

The fluidity improver has a specific surface area by nitrogen adsorption measured by the BET method of 30 m ² / g or more, preferably 5 m ² / g or more.
Those with 0 m ² / g or more give good results. Toner 1
0.01 to 8 parts by weight of the fluidity improver based on 00 parts by weight,
Preferably, 0.1 to 4 parts by weight is used.

To prepare the toner for developing an electrostatic image of the present invention, a binder resin, a colorant and / or a magnetic substance, a charge control agent or other additives are sufficiently mixed by a mixer such as a Henschel mixer or a ball mill. Melting, kneading and kneading using a hot kneading machine such as a kneader or extruder to make the resins compatible with each other, and after cooling and solidifying the melt-kneaded product, pulverize the solidified product, classify the pulverized product, and perform The toner of the invention can be obtained.

Further, the fluidity improver and the toner are sufficiently mixed by a mixer such as a Henschel mixer to obtain a toner having a fluidity improver on the surface of toner particles.

The methods for measuring the molecular weight and molecular weight distribution of the THF-soluble component, the acid value and the hydroxyl value, the ratio of the THF-insoluble component, and the glass transition temperature of the toner are as follows.

(1) Measurement of Molecular Weight The molecular weight of a chromatogram by gel permeation chromatography (GPC) is measured under the following conditions.

The column is stabilized in a heat chamber at 40 ° C., and tetrahydrofuran (THF) is passed through the column at this temperature as a solvent at a flow rate of 1 ml per minute.
After dispersing and dissolving the toner in THF, the mixture is allowed to stand overnight,
Filter through a 2 μm filter and use the filtration as a sample. The measurement is performed by injecting 50 to 200 μl of a THF solution of the resin adjusted to a sample concentration of 0.05 to 0.6% by weight. 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 prepared from several types of monodisperse polystyrene standard samples and the count number. As standard polystyrene samples for creating calibration curves,
For example, Pressure Chemical Co.
Or Toyo Soda Kogyo Co., Ltd. with 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 ,
It is appropriate to use 8.6 × 10 ⁵ , 2 × 10 ⁶ , and 4.48 × 10 ⁶ , and to use at least about 10 standard polystyrene samples. An RI (refractive index) detector is used as the detector.

In order to accurately measure the molecular weight region of 10 ³ to 2 × 10 ^6, a plurality of commercially available polystyrene gel columns may be used in combination.
rs Co., Ltd. μ-styragel 500, 10 ³ , 1
0 ⁴ 10 ⁵ of combinations and, shodex of Showa Denko Co., Ltd.
KA-801, 802, 803, 804, 805, 8
06,807 are preferred.

(2) Method of measuring acid value and OH value Method of measuring acid value The acid value is measured as follows according to JIS K 0070-1966.

Samples 2 to 10 g in 200 to 300 ml
Weighed in an Erlenmeyer flask, and acetone: toluene = 50:
About 50 ml of 50 mixed solvents are added to dissolve the resin.
Using a mixed indicator of 0.1% promthymol blue and phenol red, titration is carried out with a previously standardized N / 10 cal-alcohol solution, and the acid value is determined by the following calculation from the consumption of the alcoholic potassium solution.

Acid value (mgKOH / g) = KOH (ml
Number) × N × 5.61 / sample weight (N is a factor of N / 10KOH)

Measurement of hydroxyl value The hydroxyl value is measured by the following method according to the method described in JIS K 0070-1966.

In a 200 ml Erlenmeyer flask, about 2 g of the sample was precisely weighed in 1 mg units, and a mixed solution of acetic anhydride / pyridine = 1/4 was added with a 5 ml hole pipette.
Add 5 ml with a make cylinder. A condenser is attached to the conical flask, and the reaction is carried out in an oil bath at 100 ° C. for 90 minutes.

Add 3 ml of distilled water from the top of the cooler, shake well, and let stand for 10 minutes. With the condenser still attached, the conical flask is pulled up from the oil bath and allowed to cool. When the temperature reaches about 30 ° C., the condenser and the flask port are washed with a small amount of ascent (about 10 ml) from the upper port of the condenser. THF50
The mixture is added with a graduated cylinder and neutralized with a N / 2KOH-THF solution using an alcohol solution of phenolphthalein as an indicator using a 50 ml (0.1 ml) burette. Immediately before neutralization end point, neutral alcohol 25ml
(Methanol / ascent = 1/1 volume ratio) and titration is performed until the solution shows a faint red color. A blank test is also performed at the same time.

Next, the hydroxyl value is determined according to the following equation.

[0088]

[Outside 12]

Here, A: N / 2KOH- required for this test
Number of ml of THF solution B: Number of ml of N / 2KOH-THF solution required for blank test f: Potency of N / 2KOH-THF solution S: Sampling amount (g) C: Acid value or alkali value. However, the acid value is plus and the alkali value is minus.

(3) Ratio of THF Insoluble Content A polyester resin or a toner is weighed, and a cylindrical filter paper (for example, No. 86R size 28 × 10 mm manufactured by Toyo Roshi Kaisha, Ltd.)
Into a Soxhlet extractor. TH as solvent
Extract with 200 ml of F for 6 hours. At this time, T
The extraction is performed at a reflux rate such that the HF extraction cycle is about once every 4-5 minutes. After completion of the extraction, the cylindrical filter paper is taken out and weighed to obtain an insoluble content of the polyester resin.

When the toner contains a THF-insoluble matter such as a magnetic substance or a pigment other than the resin component, the weight of the toner put in the cylindrical filter paper is defined as W ₁ g, and the weight of the extracted THF-soluble resin component is defined as W ₁ g. Is W ₂ g, and the weight of the THF-insoluble component other than the resin component contained in the toner is W ₃ g.
The content of the THF-insoluble component of the resin component in the toner can be obtained from the following equation.

[0092]

[Outside 13]

FIG. 2 shows an example of a Soxhlet extraction apparatus. The THF 2 contained in the container 1 is heated and vaporized by the heater 8, and the vaporized THF is led to the cooler 5 through the pipe 7. The cooler 5 is constantly cooled by the cooling water 6.
The THF cooled and liquefied by the cooler 5 accumulates in the storage section having the cylindrical filter paper 3, and when the liquid level of THF becomes higher than the middle pipe 4, the THF is discharged from the storage section into the container 1. The toner contained in the cylindrical filter paper is extracted by the circulating THF.

(4) Glass transition temperature Tg Differential thermal analysis measuring device (DSC measuring device), DSC-7
(Perkin Elmer) ASTM D341
Measure according to 8-82.

The measurement sample is 5 to 20 mg, preferably 10
Weigh the mg precisely. This is put in an aluminum pan, and an empty aluminum pan is used as a reference, and the measurement is performed at a temperature rising rate of 10 ° C./min under a normal temperature and a normal humidity in a measurement temperature range of 30 to 200 ° C. In this heating process, the temperature is 40 to 10
An endothermic peak of the main peak in the range of 0 ° C. is obtained. The intersection between the line of the midpoint of the baseline before and after the endothermic peak appears and the differential heat curve is defined as the glass transition temperature Tg in the present invention.

Hereinafter, the present invention will be described with reference to resin production examples and examples, but the present invention is not limited to these examples.

[0097]

EXAMPLES Resin Production Example 1 10 mol% of terephthalic acid 25 mol% of fumaric acid 5 mol% of trimellitic anhydride 35% by mol of bisphenol derivative represented by formula (A) (R: x + y = 2.2 in propylene group) R: x + y = 2.2 with ethylene group) 25 mol%

The above-mentioned raw materials were charged into a 5-liter four-necked flask, equipped with a reflux condenser, a water separator, a N ₂ gas inlet tube, a thermometer and a stirrer, and heated at 230 ° C. while introducing N ₂ gas into the flask. A condensation polymerization reaction is performed, and Mn is 2,500
The first polyester resin A having an Mw of 10,000, a Tg of 57 ° C., a THF-insoluble content of 0%, an acid value of 28, and a hydroxyl value of 40 was obtained.

Next, 32 mol% of fumaric acid 10 mol% of trimellitic anhydride 35% by mol of bisphenol derivative represented by the formula (A) (R: x + y = 2.2 in propylene group) 2.2) 23 mol%

A condensation polymerization reaction was performed in the same manner as described above, and 2 mol% of trimellitic anhydride was further added during the polymerization. Mn was 3,500, Mw was 150,000, and Tg was 63 ° C. , THF insoluble content is 28wt
%, An acid value of 25 and a hydroxyl value of 32 were obtained as a second polyester resin B.

The obtained polyester resins A and B were mixed with 50
The parts by weight were mixed with a Henschel mixer, and Mn was 2,8.
00, Mw is 82,000, and Tg is 60
C., the THF insoluble content was 14 wt%, the acid value was 26, and the hydroxyl value was 36. 1 was obtained.

Resin Production Examples 2 to 4 The condensation polymerization was carried out in the same manner as in Production Example 1 except that the acid components and alcohol components of the first polyester resin A and the second polyester resin B were changed. . 2 to 4 were obtained.

Resin Production Example 5 30 mol% of isophthalic acid 18 mol% of terephthalic acid 10 mol% of n-dodecenylsuccinic acid 30% by mol of bisphenol derivative represented by the formula (A) (R: x + y = 2.2 in propylene group) (R : X + y = 2.2 in ethylene group) 12 mol%

Using the above monomers, a condensation polymerization reaction was carried out in the same manner as in Production Example 1. Mn was 2,200, Mw was 20,000, Tg was 56 ° C., and the THF-insoluble content was 2 wt%. And the acid value is 47 and the hydroxyl value is 3
2 was obtained. This is the binder resin N
o. And 5.

Resin Production Example 6-28 mol% of terephthalic acid- 6 mol% of n-dodecenylsuccinic acid-6 mol% of trimellitic anhydride-35 mol% of a bisphenol derivative represented by the formula (A) (R: x + y = 2.2 in propylene group) (R: x + y = 2.2 in ethylene group) 25 mol%

Using the above monomers, a condensation polymerization reaction was carried out in the same manner as in Production Example 1. Mn was 4,500, Mw was 80,000, Tg was 68 ° C., and the THF-insoluble content was 32 wt%. A polyester resin having an acid value of 14 and a hydroxyl value of 23 was obtained. This was used as a binder resin No. 6.

Resin Production Example 7 28 mol% of terephthalic acid 12 mol% of adipic acid 5 mol% of pentaerythritol 35 mol% of a bisphenol derivative represented by the formula (A) (R: x + y = 2.2 in propylene group) (R: ethylene X + y = 2.2 in the group) 20 mol%

Using the above monomers, a condensation polymerization reaction was carried out in the same manner as in Production Example 1. Mn was 3,400, Mw was 39,000, Tg was 62 ° C., and the THF-insoluble content was 20 wt%. A polyester resin having an acid value of 28 and a hydroxyl value of 47 was obtained. This was used as a binder resin No. 7 (Comparative Example).

Example 1 Binder Resin No. 1 100 parts by weight-1 part by weight of azo-based iron complex compound (1)-90 parts by weight of magnetic iron oxide (average particle size: 0.2 µm; Hc120 oersted; σs65 em u / g; σr7 emu / g)-4 parts by weight of low molecular weight polypropylene wax Department

The mixture of the above materials was melt-kneaded with a twin-screw extruder heated to 130 ° C., and the cooled mixture was roughly pulverized by a hammer mill, and the coarsely pulverized substance was finely pulverized by a jet mill. Was classified with an air classifier to obtain a magnetic toner having a weight average diameter of 6.3 μm. TH of this toner
As a result of measuring the molecular weight of the F-soluble component by GPC,
Is 770,000, Mw / Mn is 183, components in the low molecular weight region of 150,000 or less are 85%, components in the medium molecular weight region of 150,000 to 500,000 are 5%, and components in the high molecular weight region of 500,000 or more are The component was 10%. The toner contained 4% by weight of a THF-insoluble component of the polyester resin. FIG. 1 shows a GPC chart of the THF-soluble portion of the obtained toner.

To 100 parts by weight of this magnetic toner, 1.0 part by weight of hydrophobic dry silica fine powder (BET 300 m ² / g) was externally added using a Henschel mixer to form a negatively chargeable magnetic toner. did.

Using this magnetic toner, image characteristics were evaluated with a Canon digital copying machine GP-55. Table 3
As shown in the above, good results were obtained. When the fixing machine of the digital copying machine GP-55 was removed, an external drive and a temperature control function were provided, the fixing speed was changed, and a fixing test was performed. Good results as shown in Table 3 were obtained.

Examples 2 to 4 The binder resin Nos. A magnetic toner was produced in the same manner as in Example 1 except that the toner was changed to 2 to 4. Table 2 shows the molecular weight of the THF-soluble component in the toner and the ratio of the insoluble component of the polyester resin. When a test similar to that in Example 1 was performed, good results were obtained as shown in Table 3.

Examples 5 to 6 A magnetic toner was produced in the same manner as in Example 1 except that the azo iron complex compound (1) was changed to the azo iron complex compound (2) or (3). . The molecular weight of the THF-soluble component in the toner and the ratio of the insoluble component of the polyester resin are as shown in Table 2. When a test similar to that in Example 1 was performed, good results were obtained as shown in Table 3.

Example 7 In Example 1, the binder resin was no. 2, a magnetic toner was produced in the same manner as in Example 1 except that the azo iron complex compound (1) was changed to the azo iron complex compound (4). Table 2 shows the molecular weight of the THF-soluble component and the proportion of the insoluble component of the polyester resin component in the toner. Example 1
As a result, good results were obtained as shown in Table 3.

Example 8 In Example 1, the binder resin No. 3, and the magnetic toner was produced in the same manner as in Example 1 except that the azo-based iron complex compound (1) was changed to the azo-based iron complex compound (5). The molecular weight of the THF-soluble component in the toner and the ratio of the insoluble component of the polyester resin are as shown in Table 2. When a test similar to that in Example 1 was performed, good results were obtained as shown in Table 3.

Example 9 In Example 1, the binder resin was no. 4, a magnetic toner was produced in the same manner as in Example 1, except that the azo iron complex compound (1) was changed to the azo iron complex compound (6). Table 2 shows the molecular weight of the THF-soluble component and the ratio of the insoluble component in the toner.
It became as shown in. When a test similar to that in Example 1 was performed, good results were obtained as shown in Table 3.

Comparative Example 1 The azo-based iron complex compound (1) was prepared in the same manner as in Example 1 except that 3,5-
The same procedures as in Example 1 were carried out except that the chromium di-tert-butylsalicylate complex compound was changed to 2 parts by weight, and the molecular weight of the THF-soluble component and the ratio of the insoluble component in the toner are as shown in Table 2. When a test similar to that in Example 1 was performed, the results shown in Table 4 were obtained.

Comparative Example 2 In Example 1, the binder resin No. The same procedures as in Example 1 were carried out except that the composition was changed to 5, and the molecular weight of the THF-soluble component and the ratio of the insoluble component in the toner were as shown in Table 2. When the same test as in Example 1 was performed, the results shown in Table 4 were obtained.

Comparative Example 3 The binder resin of Example 1 was used. The same procedures as in Example 1 were carried out except that the composition was changed to 6, and the molecular weight of the THF-soluble component and the ratio of the insoluble component in the toner were as shown in Table 2. When a test similar to that in Example 1 was performed, the results shown in Table 4 were obtained.

Comparative Example 4 The binder resin of Example 1 was used. The same procedures as in Example 1 were carried out, except that the molecular weight was changed to 7, and the molecular weight of the THF-soluble component and the ratio of the insoluble component in the toner were as shown in Table 2. When a test similar to that in Example 1 was performed, the results shown in Table 4 were obtained.

[0122]

[Table 1]

[0123]

[Table 2]

[0124]

[Table 3]

[0125]

[Table 4]

The image density was Macbeth RD918
(Manufactured by Macbeth).

The fog was evaluated as follows. The fog density (%) was calculated from the difference between the whiteness of the printout image, the whiteness of the printout image measured by a “Reflectometer” (manufactured by Tokyo Denshoku Co., Ltd.) and the whiteness of the transfer paper, and the fog was evaluated according to the following criteria.

Evaluation criteria A: less than 1.2% B: less than 1.2 to 1.8% C: less than 1.8 to 2.5% D: 2.5 to less than 4.0% E: 4.0 %that's all

The density gradation is visually evaluated by comparing the original image with A (excellent), B (excellent), C (normal), and D (excellent).
(Somewhat bad) and E (bad) were evaluated in five paragraphs.

The environmental stability was measured under high temperature and high humidity conditions (30 degrees, 85 degrees).
% RH) for 24 hours, and an image test was performed. The image density was evaluated based on the following criteria.

Evaluation criteria A: Image density is 1.3 or more B: Image density is 1.2 to less than 1.3 C: Image density is 1.1 to less than 1.2 D: Image density is 1.0 to 1 ... Less than 1. E: image density less than 1.0

[0132]

According to the present invention, since a polyester resin having a specific molecular weight distribution is used as a binder resin, both low-temperature fixability and high-temperature offset resistance are excellent, and even in the case of fine particles, excellent halftone portions are obtained. Shows fixability and developability, and is also excellent in environmental stability.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a THF-soluble component G of the toner obtained in Example 1.
3 shows a PC chart.

FIG. 2 is a schematic explanatory view of an extraction device used for Soxhlet extraction.

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor ▲ Takashi Akira 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (56) References JP-A-7-72657 (JP, A) JP-A-3-188468 (JP, A) JP-A-7-28275 (JP, A) JP-A-6-148935 (JP, A) JP-A-61-284771 (JP, A) JP-A-4-274254 ( JP, A) JP-A-61-176949 (JP, A) JP-A-7-98519 (JP, A) JP-A-7-301954 (JP, A) JP-A-2-82267 (JP, A) (58) ) Surveyed field (Int.Cl. ⁷ , DB name) G03G 9/08

Claims (21)

(57) [Claims] 1. A negatively chargeable toner for electrostatic image development containing at least a binder resin, a colorant and a charge control agent, wherein the binder resin contains a polyester resin, and the polyester resin has an acid value of 15 to 15. 40, the hydroxyl value is 45 or less, and the soluble component of tetrahydrofuran (THF) in the toner is:
In gel permeation chromatography (GPC), the weight average molecular weight (Mw) is 100,000 or more,
Number average molecular weight (Mn) with respect to weight average molecular weight (Mw)
The ratio (Mw / Mn) is 35 or more, the content of the components in the low molecular weight region having a molecular weight of 150,000 or less is 70 to 94%, and the content of the components in the medium molecular weight region of 150,000 to 500,000 is 1 to 10% and the content of components having a molecular weight of 500,000 or more high molecular weight region is 5-25%, and rather a multi than of component is a medium molecular weight region of the high molecular weight region, a charge control agent an azo A negatively chargeable toner for developing an electrostatic image, wherein the toner is a series iron complex compound . 2. The charge control agent has the following formula: [Wherein X ₁ and X ₂ represent a hydrogen atom, a lower alkyl group,
Represents a lower alkoxy group, a nitro group or a halogen atom, and X ₁ and X ₂ may be the same or different;
m and m 'represents an integer of 1 to 3, _{R 1} and _{R 3} is a hydrogen _atom, an alkyl of C _{1 ~ 18,} alkenyl, sulfonamide, mesyl, sulfonic acid, carboxy ester,
It represents _hydroxy, alkoxy of C _{1 ~ 18,} acetylamino, benzoylamino group or a halogen atom, R
₁ and R ₃ may be the same or different, n and n ′ represent an integer of 1 to 3, R ₂ and R ₄ represent a hydrogen atom or a nitro group, A ⁺ represents a hydrogen ion, sodium Represents an ion, potassium ion or ammonium ion. The negatively chargeable toner for developing an electrostatic image according to claim 1, which is an azo-based iron complex compound represented by the following formula: 3. A negatively chargeable toner according to claim 1 or 2 ratio of THF-insoluble matter of polyester resin is 0-10% in the toner. 4. An azo-based iron complex compound comprising a binder resin 100
The negatively chargeable toner for developing an electrostatic image according to any one of claims 1 to 3 , wherein the toner is contained in an amount of 0.1 to 10 parts by weight per part by weight. 5. An azo-based iron complex compound comprising: a binder resin 100;
4. The composition according to claim 1, wherein the content is 0.1 to 5 parts by weight per part by weight.
3. The negatively chargeable toner for developing an electrostatic image according to any one of 3 . 6. The azo iron complex compound is a compound selected from the group consisting of the following azo iron complex compounds (1), (2), (3), (4), (5) and (6). The negative band for developing an electrostatic image according to any one of claims 1 to 5.
Electrical toner. [Outside 2] [Outside 3] [Outside 4] 7. The negatively chargeable toner according to any one of claims 1 to 6 colorant is a magnetic material. 8. The magnetic material is used in an amount of 10 parts by weight per 100 parts by weight of the binder resin.
The negatively chargeable toner for developing an electrostatic image according to any one of claims 1 to 7 , which is contained in an amount of from 200 to 200 parts by weight. 9. toner THF-soluble matter is, Mw of 200,000 to 3,000,000 negatively chargeable toner according to any one of claims 1 to 8. 10. The THF soluble component of the toner is Mw / Mn.
The negatively chargeable toner for developing an electrostatic image according to any one of claims 1 to 9 , wherein the value is 40 to 400. 11. The THF-soluble component of the toner has a molecular weight of 50.
The negative for electrostatic charge image development according to any one of claims 1 to 10 , wherein a component in a high molecular weight region of 10,000 or more is contained by 1 to 20% more than a component in a medium molecular weight region of 150,000 to 500,000.
Chargeable toner. 12. The binder resin has a THF-insoluble content of 1%.
Negatively chargeable toner according to any one of claims 1 to 11 or less 0 wt%. 13. binder resin for developing an electrostatic charge image according to any one of claims 1 to 12 or does not contain a THF-insoluble matter, or the content of THF-insoluble matter is not more than 5 wt%
Negatively chargeable toner. 14. The polyester resin has a hydroxyl value of 5 to 5.
42 negatively chargeable toner according to any one of claims 1 to 13. 15. The polyester resin is negatively chargeable toner according to any one of claims 1 to 14 a glass transition temperature of 40 to 80 ° C.. 16. The polyester resin is negatively chargeable toner according to any one of claims 1 to 15 a glass transition temperature of 45 to 75 ° C.. 17. The toner has a THF insoluble content of 5 to 30 watts.
Melt-kneading a mixture containing at least a polyester resin containing at least t%, a colorant, and a charge control agent, cooling the kneaded material, and having toner particles formed by grinding the cooled material. negatively chargeable toner according to any one of claims 1 to 16. 18. The polyester resin is negatively chargeable toner according to any one of claims 1 to 17 containing 10 to 25 wt% of THF-insoluble matter. 19. A toner comprising (i) a first polyester resin containing no THF-insoluble matter, having a Mw of 7000 to 100,000 and a Mn of 2,000 to 10,000, and containing no THF-insoluble matter; ii) THF insoluble content is 10 to 50 wt%
A second polyester resin having a THF-soluble component Mw of 30,000 to 500,000 and Mn of 2500 to 15000, (iii) a colorant, and (iv) a charge control agent. the mixture was melt-kneaded you are in, the kneaded product was cooled, negatively chargeable toner according to any one of claims 1 to 18 has toner particles produced by grinding cooled product . 20. The mixing weight ratio of the first polyester resin and second polyester resin is 1: 9 to 9: negative for electrostatic image development according to a is any one of claims 1 to 19 1
Chargeable toner. 21. The mixing weight ratio of the first polyester resin and second polyester resin is 2: 8 to 8: 2. It claims 1 to 20 negative for electrostatic image development according to any one of
Chargeable toner.