JPH0561249A - Electrostatic charge image developing toner - Google Patents

Abstract

PURPOSE:To obtain a toner adapted to heat roll fixing for developing an electrostatic charge image in electrophotography, electrostatic recording, and electrostatic printing. CONSTITUTION:The binder resin contained in the toner is characterized by containing a fraction insoluble in tetrahydrofuran, and a fraction having a molecular weight of >=1X10<7> in an amount of 5-30%, and it is made of a vinyl type polymer having a main peak in a GPC molecular weight of 2X10<4>-1X10<5>, and a weight average molecular weight of 2X10<4>-2X10<5> and a number average molecular weight of 1X10<3>-1X10<4> in a molecular weight distribution of <=1X10<7>, and it is in a Tg of 55-75 deg.C, thus permitting the obtained toner to be fixable with small heating, superior in offset resistance and pulverizability and productivity at the time of manufacture, and freed of filming even in the case of high speed system.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to electrophotography, electrostatic recording,
The present invention relates to a toner for developing an electrostatic charge image in electrostatic printing or the like. It is also applicable to dry toner for laser printers and other toners used for copying having a heat roll fixing mechanism.

[0002]

2. Description of the Related Art In the toner used in a copying machine having a fixing mechanism of a heating roller, since the heating roller surface and the toner image are in contact with each other under pressure in a melted state, a part of the toner image passes through the roller surface. A paper offset phenomenon occurs.
As a resin improvement to avoid the offset phenomenon, Japanese Patent Publication No. 51-23354 proposes a toner using a crosslinked polymer as a binder resin. According to this method, it is effective in improving the offset resistance and the abrasion resistance, but the fixing temperature is sufficiently low, the offset resistance and the abrasion resistance are good, and the fixing characteristics are not obtained. .. Further, as the amount of cross-linking component increases, the pulverizability deteriorates. Therefore, it is difficult to satisfy the offset resistance and the crushability with high performance. In addition, although some proposals have recently been made to improve the polymerization method and to define the range of the molecular weight distribution, there is no resin satisfying both the fixability and the pulverizability. Other problems with the resin include filming and fusion to the photoreceptor.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned prior art and has the following objects. 1) Providing a toner suitable for a heat roll fixing method, 2) Providing a toner having an excellent hot offset property, 3) Providing a toner with good productivity by increasing pulverizability and pigment dispersibility during production. 4) To provide a binder resin with a small power load during toner kneading in a pulverized toner production line.

[0004]

The present invention is characterized in that the binder resin contained in the toner contains no THF insoluble matter and contains 5 to 30% of a component having a molecular weight of 1 × 10 ⁷ or more. It is an electrostatic image developing toner.

That is, in kneading a toner, when a binder having a THF insoluble content of 30 to 70% as a binder resin, and a pigment and a charge control agent which are other toner components are kneaded, TH is generated by mechanical energy at the time of kneading.
The F insoluble component is cleaved to obtain a toner containing no THF insoluble component and containing 5 to 30% of a component having an average molecular weight of 10 ⁷ or more in the THF soluble component. In addition, this toner has a molecular weight distribution of GPC of THF dissolved content of 20
It is kneaded so that the main peak exists in the region of 00 to 100,000.

This polymer is a binder resin having a Tg in the range of 55 to 75 ° C., and the toner obtained by using the binder resin provides a toner having well-balanced properties such as hot offset fixability and crushability. The molecular weight distribution of this binder resin is shown in FIG. Of these, a component insoluble in THF and containing 1 × 10 ⁷ or more is called a microgel.

With respect to the above contents, by devising the ratio of the crosslinkable component (measured as the THF insoluble component) and the ratio of the THF soluble component, the relationship of fixing property, pulverizability, hot offset, etc. When it is dissolved in the solvent, it can be separated into an insoluble component and a soluble component, and the soluble component can be measured for molecular weight distribution by GPO.

Focusing on the peak positions of the molecular weight distributions of the THF insoluble matter and the soluble matter and the amounts of the components, the THF insoluble matter works against the fixability but is effective for the hot offset.

If the amount of insoluble matter is too large, the load is too high when the toner is kneaded by the kneader, so that the amount of material to be supplied must be reduced, resulting in poor productivity and variability in quality. ..

On the other hand, some inventions using a binder resin having a molecular weight range of less than 1 × 10 ⁷ have been proposed, but none of them has resulted in satisfactory results. As a result of research on these, the following facts were newly found regarding pulverizability and fixability based on molecular weight distribution and hot offset.

1. 1x10 with no THF insoluble matter
^{When a} binder resin having a molecular weight range of ⁷ or more is used for the toner, the pulverizability and fixing property are not deteriorated, and a great effect can be obtained for filming and hot offset. 2. The binder resin having the above-mentioned molecular weight range can be obtained by cutting the resin containing a THF-insoluble matter by mechanical energy. 3. At this time, a component having a molecular weight range of less than 1 × 10 ⁷ has a weight average molecular weight of 20,000 to 200,000 and a number average molecular weight of 1,000 in view of a balance with fixing property and basic image characteristics.
A vinyl polymer having a molecular weight range of 10,000 to 10,000 is preferable, and this binder resin has a thermal property of Tg55.
What is in the range of ~ 75 ° C is preferable.

To explain the above items in more detail, GPC is measured as follows. That is, 40
The column was stabilized in a heat chamber at ℃, and THF as a solvent was flowed through the column at a flow rate of 1 ml / min to prepare a THF sample solution of a resin prepared to a sample concentration of 0.05 to 0.6% by weight. Measure by injecting 50 to 200 microliters. In measuring the molecular weight of the sample, the molecular weight distribution of the sample was calculated from the function of the logarithmic value and the count number of a calibration curve prepared from several kinds of monodisperse polystyrene standard samples. As a standard polystyrene sample for preparing a calibration curve, for example, Pressure Chem
ical Co. Alternatively, the molecular weight of Toyo Soda Kogyo Co., Ltd. is 6 × 10 ² , 2.1 × 10 ³ , 4 × 10 ³ , 1.75 × 1.
0 ⁴ , 5.1 × 10 ⁴ , 1.1 × 10 ⁵ , 3.9 × 10 ⁵ ,
It is suitable to use those of 8.6 × 10 ⁵ , 2 × 10 ⁶ , and 4.48 × 10 ⁶ , and to use at least about 10 standard polystyrene samples. In addition, the detector is RI (refractive index)
Use a detector. Although the molecular weight distribution of the resin is measured in this way, it is practically difficult to detect 10 ⁷ or more with the current column. On the other hand, the presence of a molecular weight range of 10 ⁷ or higher in the detection limit of GPC molecular weight was found in the THF-soluble part,
Moreover, this molecular region affects the fixability, pulverizability, and offset. As a method for measuring the molecular weight range of 1 × 10 ⁷ or more in the THF-dissolved portion, it can be determined by utilizing a resin fractionation method. That is, a resin-insoluble solvent may be added to THF and the ratio of THF to the solvent may be determined while observing the molecular weight distribution. This time, a mixed solvent of THF and isododecane was used, and fractionation was performed at 25 ° C.
The ratio of THF / isododecane is 2 ± 0.5 / 3 ± 1.5
Is suitable, and the liquid in which the resin part is dissolved at this ratio is GPC.
Is the range of molecular weight measurement of. In addition, the THF insoluble fraction and the test method for fractionation are measured as follows. Resin about 1.0
Weigh g, add about 50 g of THF to this, and add 2 at 20 ° C.
Let stand for 4 hours. First, this is separated by centrifugation, and filtered at room temperature using a quantitative filter paper of JIS standard (P3801) Type 5C. Subsequently, the filter paper residue is an insoluble component and is represented by the ratio (% by weight) of the resin used and the filter paper residue. In the case of a solvent for fractionation, THF may be changed to this solvent. The microgel content can be calculated by calculating the THF / isododecane insoluble content and the THF insoluble content from the amount of the THF soluble component.

To obtain the resin for toner of the present invention, for example, a low molecular weight polymer having a weight average molecular weight of 50,000 or less obtained by a two-step polymerization method is synthesized, and (I) it is once applied 20 times.
The temperature is lowered to below ℃ and the crosslinked polymer (I
Add the monomer for I) and mix well with the core polymer. As a result, the polymer (1) is dissolved in the monomer (II) or adheres around (I). (II)
The monomer for use is obtained by suspension polymerization by adding a crosslinking agent in an amount of 0.2 to 1% by weight based on the total amount of monomers. This will be described in more detail. In the one-step polymerization, the aqueous suspension polymerization is carried out in a system containing no crosslinking agent. At this time, in order to reduce the molecular weight, it is preferable to use a molecular weight modifier as mentioned in the examples. As a specific method, a reactor equipped with a stirrer, the above-mentioned monomer,
A reaction initiator, a molecular weight modifier, a dispersant, and ion-exchanged water are charged and suspension polymerization is carried out at 95 to 100 ° C. The reaction is completed in 5-8 hours. Next, the temperature is lowered to 20 ° C. or lower. Next, a monomer for two-step polymerization is charged. This monomer and other materials may be the same as in the first stage except that they contain a crosslinking agent. Charge the monomer for the two-step polymerization at 20 ° C or below and
Stir for 4 to 48H. At this time, the total weight ratio of the 1st stage monomer and the 2nd stage monomer is preferably 1st stage / 2nd stage: 3/7 to 8/2. When the number of monomers in the first stage is 3 or less, the target molecular weight of the low molecular weight polymer cannot be obtained, and when it is 8 or more, the polymer in the crosslinked region cannot be obtained. Further, the crosslinkable monomer used in the second stage is preferably 0.2 to 1.0% by weight. If the amount is out of this range, the molecular weight required for kneading the toner cannot be obtained. By stirring at a temperature of 20 ° C. or less, the one-stage polymer is dissolved in the two-stage polymer or fused with the one-stage polymer, and the two-stage reaction is performed in 60 to 1
When it is carried out at 00 ° C., one having no crosslinking component and one having one can be synthesized in one particle. A characteristic of the two-step polymerization method is that by synthesizing a low molecular weight region and a high molecular weight component at the resin stage, it is easy to obtain a target molecular weight later by mechanical energy. With this method, a toner having a wider molecular weight range can be obtained as compared with the suspension polymerization in one step. Of course, the resin for toner of the present invention can obtain the target molecular weight of the resin obtained by the one-step polymerization method by mechanical energy, but in this case, the kneading conditions need to be set more severely.

As the component of the vinyl polymer in the present invention, it is preferable to use a vinyl copolymer obtained by polymerizing styrene in an amount of 50 to 100% by weight, preferably 60 to 90% by weight. If the styrene copolymerization amount is less than 50% by weight, the heat melting property of the toner is poor, and as a result, the fixing property tends to be insufficient. In the present invention, as the vinyl-based monomer other than styrene, which is a component of the vinyl-based polymer, α-methylstyrene, p-methylstyrene, pt
styrene derivatives such as ert-butyl styrene and p-chlorostyrene, methacrylic acid, methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, pentyl methacrylate, hexyl methacrylate, heptyl methacrylate, octyl methacrylate, methacrylic acid. Nonyl acid, 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, methacryl Phenoxyethyl methacrylate phenoxydiethylene glycol methacrylate phenoxy tetraethylene glycol, benzyl methacrylate, cyclohexyl methacrylate, tetrahydrofurfuryl methacrylate, methacrylic acid dicyclopentenyl,
Dicyclopentenyloxyethyl methacrylate, N-vinyl-2-pyrrolidone methacrylate, methacrylonitrile, methacrylamide, N-methylolmethacrylamide, 2-hydroxyethyl methacrylate, hydroxypropyl methacrylate, hydroxybutyl methacrylate,
2-Hydroxy-3-phenyloxypropyl methacrylate, diacetone acrylamide, acrylic acid, methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, pentyl acrylate, hexyl acrylate, hebutyl acrylate, acrylic acid Octyl, nonyl acrylate, decyl acrylate, undecyl acrylate, dodecyl acrylate, glycidyl acrylate, methoxyethyl acrylate, propoxyethyl acrylate, butoxyethyl acrylate, methoxydiethylene glycol acrylate, ethoxydiethylene glycol acrylate, methoxy acrylate Ethylene glycol, butoxytriethylene glycol acrylate, methoxydipropylene glycol acrylate, phenoxyethyl acrylate, acrylic Phenoxyethyl glycol, acrylic acid phenoxy tetraethylene glycol, benzyl acrylate, cyclohexyl acrylate,
Tetrahydrofurfuryl acrylate, dicyclopentenyl acrylate, dicyclopentenyl oxyethyl acrylate, N-vinyl-2-pyrrolidone acrylate, hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxybutyl acrylate, 2-hydroxy acrylate A vinyl monomer having one vinyl group in one molecule such as -3-phenyloxypropyl, glycidyl acrylate, acrylonitrile, acrylamide, N-methylol acrylamide, diacetone acrylamide, vinyl pyridine is used as the main component, but Reaction products of divinylbenzene, glycol with methacrylic acid or acrylic acid, such as ethylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate, 1,4-butanediene. Over dimethacrylate, 1,5
-Pentanediol dimethacrylate, 1,6-hexanediol dimethacrylate, neopentyl glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, tripropylene glycol dimethacrylate, hydroxypivalic acid neopentyl glycol ester diester Methacrylate, trimethylolethane trimethacrylate, trimethylolpropane trimethacrylate, pentaerythritol trimethacrylate, pentaerythritol tetramethacrylate, trismethacryloxyethyl phosphate, bis (methacryloyloxyethyl) hydroxyethyl isocyanurate, tris (methacryloyloxyethyl)
Isocyanurate, ethylene glycol diacrylate, 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, hydroxypivalate neopentyl glycol diacrylate, trimethylolethane triacrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, trisacryloxyethyl phosphate, bis (methacryloyloxyethyl) hydroxy Ethyl isocyanurate, tris (methacryloyloxyethyl) isocyanate Nute, glycidyl methacrylate and methacrylic acid or acrylic acid half ester, bisphenol epoxy resin and methacrylic acid or acrylic acid half ester, glycidyl acrylate and methacrylic acid or acrylic acid half ester, etc. A vinyl monomer having two or more vinyl groups is used.

Of these, a preferable vinyl-based monomer is 1 vinyl-based monomer per molecule, and 1 is a vinyl-based monomer.
In the vinyl-based monomer having one vinyl group in the molecule,
Examples thereof include styrene, a styrene derivative, a methacrylic acid ester, and an acrylic acid ester, and styrene and an alkyl ester of methacrylic acid or acrylic acid having 1 to 5 carbon atoms in the alkyl group are particularly preferable. Among vinyl monomers having two or more vinyl groups in one molecule, divinylbenzene, dimethacrylate and diacrylate of methylene glycol having 2 to 6 carbon atoms are preferable.

These monomers are blended so that the total is 100% by weight. Among these, the amount of the vinyl-based 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, etc., but the economical efficiency, the stability during production, etc. From the point of view, it is preferably produced by aqueous suspension polymerization.

The radical initiator used in the polymerization of the above-mentioned monomer or monomer mixture is 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,
Cyclohexanone di-tert-butylperoxyketal, 2-octanone di-tert-butylperoxyketal, acetone di-tert-butylperoxyketal, peroxide radical initiators such as diisopropyl pentene hydroperoxide, 2,2'-azobisiso Butyronitrile, 2,2'-azobis (2,4-dimethylpareronitrile), 2,2'-azobis (4-methoxy-2,4-dimethylvaleronitrile), dimethyl 2,2'-azobisisobutyrate, There are azobis radical initiators such as 1,1′-azobis (cyclohexane-1-carbonitrile). These are preferably 0.01 to 20% by weight, particularly preferably 0.1% by weight, based on the total amount of the monomers.
Use from 1 to 10% by weight.

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

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

The toner binder resin obtained as described above is appropriately melt-mixed with a colorant and / or magnetic powder and, if necessary, a charge control agent and other additives to prepare an electrostatic image developing toner. be able to.

As the coloring agent, carbon black, iron oxide pigment, phthalocyanine blue, phthalocyanine green, rhodamine 6G lake, Watching red strontium, etc. can be used. Select and use the range appropriately.

As the magnetic powder, for example, iron, manganese,
There are fine metal powders such as nickel and cobalt and ferrites such as iron, manganese, nickel, cobalt and zinc, and those having an average particle size of 10 μm or less, particularly 1 μm or less are preferable, and usually 0 to 70% by weight in the toner. use.

As the charge control agent, 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 can be used, and it is usually used in an amount of 0 to 20% by weight in the toner.

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, and these are usually used. Used in toner in an amount of 0 to 10% by weight.

Next, mechanical energy is used to cut the molecules in the molecular weight range of the THF-insoluble portion, so that the microgel component becomes 5 to 30.
%, The resin containing the THF insoluble matter obtained by the method B) is kneaded with only the resin.
When kneading, the kneading is performed with a kneader such as a hot roll, a pressure kneader, a Banbury mixer, a uniaxial or biaxial continuous kneader.
In this kneading, there is a region where molecules are cut by mechanical energy. This is mainly controlled by the viscosity during kneading.

The viscosity is 10 ⁴ to 10 ⁷ poise. When kneaded at a viscosity higher than this viscosity range, the molecules are difficult to be cut and the THF insoluble component remains in the resin. Further, when kneading at a viscosity higher than this viscosity range, the mechanical load is large and the power is over and the material supply is lowered.

Further, even when operated with a strong energy, the heat generation is large and the temperature control is difficult and the quality varies.

When kneading in the above viscosity range, THF is used.
The conditions for microgel formation vary depending on the insoluble content and the kneading conditions, but the preferred THF insoluble component is 20 to 70%.

Naturally, if the THF insoluble component is small, the microgel content is small, and if it is large, the viscosity is high and the mechanical load is large.

The advantage of this method is that the microgel can be controlled relatively easily. On the other hand, it is difficult to control and control the formation of microgels by polymerization or the like.

As a toner property, this microgel has a great effect on hot offset and filming. In order to take full advantage of this property, it is necessary to specify the molecular weight of components other than the microgel.

That is, as a balance of the amount ratio, it is suitable that the content of the microgel is 5 to 30%, the weight average molecular weight of the components other than the microgel component is 20,000 to 200,000, and the number average molecular weight is 1,000 to 10,000.

If the amount of microgel is small, there is no effect on hot offset and filming, and if it is large, the fixability deteriorates.
Further, if the molecular weight is low, heat-resistant storage stability becomes a problem, and if it is high, the fixability becomes unacceptable.

In addition to the above-mentioned molecular weight characteristics, it is necessary that Tg is 55 to 75 ° C. as a thermal characteristic. In this range, basic image characteristics as well as storability are secured.

In addition, it has been found that the toner using this microgel also has an improved carbon dispersibility. It is considered that the kneading effect is improved because the viscosity necessary for toner dispersion during the toner kneading is increased by the inclusion of the microgel.

Regarding the toner productivity, since the THF insoluble content was not included, the kneading property was good and the toner productivity was improved by 30 to 70%.

The toner binder resin obtained as described above is appropriately melt-mixed with a colorant and / or magnetic powder and, if necessary, a charge control agent and other additives to obtain an electrostatic image developing toner. be able to.

As the colorant, carbon black, iron oxide pigment, phthalocyanine blue, phthalocyanine green, rhodamine 6G lake, Watching red strontium, etc., which are conventionally known, can be used. Select and use the range appropriately.

As the magnetic powder, for example, iron, manganese,
There are fine metal powders such as nickel and cobalt and ferrites such as iron, manganese, nickel, cobalt and zinc, and those having an average particle size of 10 μm or less, particularly 1 μm or less are preferable, and usually 0 to 70% by weight in the toner. use.

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

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, and these are usually used. Used in toner in an amount of 0 to 10% by weight.

As a method for producing the toner, the toner is premixed by a mixer such as a V blender or a Henschel mixer, and kneaded by a two-roll, three-roll, single- or twin-screw kneader.

After cooling, coarse pulverization is carried out with a hammer mill, pulperizer, pin mill feather mill or the like and finely pulverized with jet air. Classifying with Macucut, Alpine, etc. 5
Adjust to a particle size of 30 μm.

[0045]

【Example】

Examples 1 to 3, Comparative Examples 1 and 2 3 equipped with a cooling pipe, a stirrer, a gas introduction pipe and a thermometer
Charge the ion-exchanged water and the monomer to the 1-liter flask. The formulation examples are shown in Table 1 as Examples 1 to 3 and Comparative Examples 1 and 2. The liquid was heated with stirring, the reaction temperature was raised to the specified reaction temperature, and the reaction time was 12 hours. The obtained polymer was washed with water and dried at room temperature of 10 torr to obtain a powdery powder having a volatile content of 1% or less.

Resins 300 of Examples 1 to 3 and Comparative Examples 1 and 2
g, carbon black (Sanyo Kasei Co., Ltd. # 40)
20 parts, Oil Black BY (Orient Chemical) 25
g was melted and kneaded by heating with a twin roll. See Table 1 for conditions and results. This was roughly crushed with a hammer mill and finely crushed with a jet air mill. The particles were classified to have a particle size of 10 to 11 μm. Next, 50 g of toner and EFV200 / 300
(Nippon Iron Powder Co., Ltd.) (950 g) was mixed and shaken thoroughly to obtain a developer.

The developer was evaluated in FT7500, a copying machine RICOH. The pulverizability of the toner can be expressed by the processing amount of the pulverizable toner per unit time. In the case of this toner, the air pressure is 5 kg / cm ² .

Compared with Examples 1 to 3, M soluble in THF
When the ratio of w10 ⁷ or more is small, the hot offset is bad and the filming is bad. On the other hand, if the amount is large, the hot offset is good but the crushing and fixing properties are poor. Therefore, the balance between the two is good in Examples 1 to 3.

[Table 1] ━━┛

Examples 4 to 6, Comparative Examples 3 and 4 300 g of the resins of Examples 4 to 6 and Comparative Examples 3 and 4, 20 parts of carbon black (Sanyo Kasei Co., Ltd. # 40), Oil Black BY (Orient) 25g of 2)
It was melted and kneaded by heating. See Table 2 for conditions and results. This was roughly crushed with a hammer mill and finely crushed with a jet air mill. The particles were classified to have a particle size of 10 to 11 μm. Next, 50 g of toner and EFV200 / 300 (made by Nippon Iron Powder)
950 g was mixed and shaken well to obtain a developer.

[0051]

[Table 2] ━━┻━━━┛

Mw10 of the THF-soluble matter as compared with the examples
^When the ratio of ⁷ or more is small, the hot offset is bad and the filming is bad. On the other hand, if the amount is large, the hot offset is good, but the crushing and fixing properties are poor. Therefore, the balance between the two is better in the embodiment.

[0053]

INDUSTRIAL APPLICABILITY The toner of the present invention is a toner having a good fixing property, a low heat fixing property, an excellent offset resistance, a good pulverizability at the time of production and a good productivity, and a filming property. It is an excellent product that does not occur even in high-speed systems.

Claims (3)

[Claims] 1. The binder resin contained in the toner,
An electrostatic charge image developing toner characterized by containing 5 to 30% of a component having a molecular weight of 1 × 10 ⁷ or more without containing THF insoluble matter. 2. The molecular weight distribution of the THF-dissolved component by gel permeation chromatography (GPC),
The toner for developing an electrostatic charge image according to claim 1, which has a main peak in a region of 2000 to 100,000. 3. The binder resin has a weight average molecular weight of 20,000 to 200 in a molecular weight distribution of less than 1 × 10 ^7.
The toner for developing an electrostatic image according to claim 1, which comprises a vinyl polymer having a number average molecular weight of 1,000 to 10,000 and a Tg of 55 to 75 ° C.