JPH11143114A - Electrostatic charge image developing toner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrostatic charge image developing toner which can highly satisfy the requirements of fixing property and offset resistance while maintaining high developing property in various environments for repeated use, and which does not cause deposition or sticking of the toner or a paper powder component on a pressurizing roller or a heating roller of a fixing machine. SOLUTION: In the electrostatic charge image developing toner containing at least a binder resin and a wax, the toner contains two kinds of waxes (A) and (B) having the following properties. The wax (A) shows the endothermic main peak measured by differential scanning calorimeter(DSC) at 50 to 130 deg.C and has <=20 deg.C half-width of the endothermic main peak, while the wax (B) is a polypropylene wax having 1 to 30 mg KOH/g acid value.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrostatic image developing toner 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.
Many methods are known as described in Japanese Patent Application Laid-Open Publication No. Sho. 43-24748, and the like. Generally, a photoconductive substance is used to form an electric latent image on a photoreceptor by various means. Formed, and then developed by attaching toner to the latent image to form a visible image.If necessary, the toner image is transferred to a transfer material such as paper, and then the toner image is transferred to the transfer material by heat, pressure, or the like. This is to obtain a copy after fixing. Further, toner particles remaining on the photoconductor without being transferred to the transfer material are removed from the photoconductor by a cleaning process.

In recent years, devices using electrophotography have begun to be used not only for conventional copiers but also for printers and facsimile machines for computer output. For example, as for printer devices, LBP printers or LED printers have become mainstream in the market these days, and the direction of technology is as follows.
Conventionally, 240, 300 dpi was replaced with 400, 60
0, 800, and even higher resolutions of 1200, 2400 dpi. Accordingly, a higher definition has also been required for the developing system. With the advancement of computers, the output images are required to have higher definition and higher image quality.Moreover, with the spread of personal computers, maintenance can be performed more easily and at the same time, higher As the reliability has been strictly pursued, the performance required of the printer has become higher, and a better machine cannot be realized unless the performance of the toner can be improved. For example, one of the important performances required for toner in digital printers and copying of high-resolution images is fixing performance. Various methods and apparatuses have been developed for the fixing step, but the most common method at present is a pressure heating method using a heating roller. The pressure heating method using a heating roller performs fixing by allowing the toner image surface of the sheet to be fixed to pass through the surface of the heating roller having a surface formed of a material having releasability with respect to the toner while pressing the surface under pressure. It is. In 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, and the fixing can be performed quickly. Can,
Very effective in high speed electrophotographic copiers.

[0004] However, in the heat roller fixing method, there is a problem that components derived from toner and paper adhere to the surfaces of the heating roller and the pressure roller due to continuous high durability, thereby causing the transfer paper to be stained. is there.

Conventionally, for the purpose of preventing the toner from adhering to the surface of the fixing roller, for example, the roller surface is formed of a material having excellent releasability with respect to the toner, such as silicone rubber or a fluorine-based resin. In order to prevent fatigue, the roller surface is coated with a thin film of a liquid having good releasability such as silicone oil. However, although this method is effective in preventing toner offset, it requires a device for supplying an anti-offset liquid, and thus has problems such as a complicated fixing device.

Accordingly, a method of adding a wax such as low molecular weight polyethylene or low molecular weight polypropylene to the toner has been proposed based on the idea of supplying the anti-offset liquid during heating from the toner instead of using a silicone oil supply device or the like. It is proposed in Japanese Patent Publication No. 52-3304, Japanese Patent Publication No. 52-3305, Japanese Patent Publication No. 57-52574, and the like. When wax such as low molecular weight polyethylene and low molecular weight polypropylene is added,
The low-temperature fixability and offset resistance of the toner are greatly improved. However, while these properties are improved, the use of wax deteriorates the fluidity of the toner and causes problems such as blocking.

To solve this problem, Japanese Patent Application Laid-Open No.
In 39365, polypropylene has an acid value,
We are working to improve liquidity.

[0008] Further, as a toner containing two or more types of wax in order to exhibit the effect of adding wax from a low temperature region to a high temperature region, for example, Japanese Patent Publication No.
JP 3305, JP-A-58-215659, JP-A-62-100775, JP-A-4-12467
6, JP-A-4-299357, JP-A-4-299357
Techniques such as Japanese Patent No. 329553 and Japanese Patent Application Laid-Open No. 5-197192 are disclosed.

[0009] However, none of these toners can satisfy all the required performances, causing some problems. For example, high-temperature offset resistance and developability are excellent, but low-temperature fixability is just one step away, or low-temperature offset resistance and low-temperature fixability are excellent, but blocking resistance is slightly inferior and developability decreases. And the offset resistance at low and high temperatures is not compatible.Blotch occurs due to uneven toner coating due to free wax components, causing image defects and fogging on the image. Was happening.

Further, Japanese Patent Application Laid-Open No. 7-281478 proposes a toner using a combination of a polypropylene resin and a polyethylene resin having an acid value as a wax.

However, even in this case, there is no sufficient measure against a phenomenon in which a lump composed of a component derived from paper and a component derived from toner caused by high durability is generated on the fixing roller. Further improvement of the toner has been desired.

[0012]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and to provide a high-quality image for a long period of time in each environment. An object of the present invention is to propose a highly durable toner for developing an electrostatic image without causing any problem.

[0013]

According to the present invention, there is provided an electrostatic image developing toner having at least a binder resin and a wax, wherein the wax has an endothermic main peak measured by a differential scanning calorimeter (DSC) of 50 to 50%. It is characterized by having a wax (A) which is in the range of 130 ° C. and has a half width of the endothermic main peak of 20 ° C. or less, and a polypropylene-based wax (B) having an acid value of 1 to 30 mgKOH / g. And a toner for developing an electrostatic image.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, the use of the wax described below is excellent in low-temperature fixability and offset resistance, and adheres and adheres to a heating roller and a pressure roller of a fixing device even with high durability. And a toner for developing an electrostatic image which does not cause image defects can be obtained.

That is, a polypropylene wax having an acid value can increase the range of low-temperature fixing property and high-temperature offset property, and can improve the releasability from a roller at a high temperature. Further, the wax (A) is effective in improving the low-temperature melting property and the releasability in a wide temperature range. Further, the toner of the present invention having the above two kinds of waxes has high releasability, so that the wax adhering to the fixing roller is also suppressed, whereby the paper powder and the component derived from the toner adhere to the fixing roller. Can be suppressed.

Hereinafter, each material will be described more specifically. The wax (A) used in the present invention has an endothermic main peak measured by DSC in the range of 50 to 130 ° C, and has a half-value width of 20 ° C or less (preferably 5 to 18 ° C). It is characterized by being.

If the endothermic main peak is lower than 50 ° C., there arises a problem in storage stability, and a problem such as blocking occurs in the toner container due to the high durability of the toner. If the endothermic main peak exceeds 130 ° C., the toner fixing performance is adversely affected.

The half-width of the endothermic main peak is 20
When the temperature is within ° C., the resin melts rapidly in a certain temperature range, imparts a plasticizing effect to the binder resin, and improves offset resistance and fixability. The half width of the endothermic main peak is 20
If the temperature exceeds ℃, sharp melting property cannot be exhibited, so that sufficient releasability from the fixing roller cannot be obtained or storage performance is adversely affected.

In the present invention, the endothermic peak temperature of the wax is measured by a differential thermal analyzer (DSC), DS
Using C-7 (manufactured by PerkinElmer), the measurement was performed under the following conditions.

Sample: 5 to 20 mg, preferably 10 mg Measurement method: A sample is placed in an aluminum pan, and an empty aluminum pan is used as a reference.

Temperature curve: Temperature rise I (20 ° C. → 180 ° C., temperature rise rate 10 ° C./min.) Temperature fall I (180 ° C. → 10 ° C., temperature fall rate 10 ° C./mi)
n. ) Heating II (10 ° C → 180 ° C, heating rate 10 ° C / mi)
n. ) The endothermic peak temperature measured at the temperature rise II is defined as a measured value.

As the wax (A) preferably used in the present invention, a polyethylene wax mainly composed of polyethylene having the following general formula is preferably used.

Since-(CH ₂ CH ₂ ) _n -polyethylene wax has a larger dispersion diameter than polypropylene wax, releasability from a roller is remarkably improved.

Examples of the polyethylene wax include a homopolymer of ethylene and a copolymer of ethylene and another olefin (particularly, propylene is preferable). It is necessary that the ethylene copolymer has an ethylene component of 60% by weight or more.

The method for producing the polyethylene wax used herein includes a method of radically polymerizing ethylene under high pressure, a method of polymerizing ethylene under a low pressure with a Ziegler catalyst, and a method of producing a high molecular weight polyethylene resin obtained by these methods. There are a method of thermal degradation, a method of obtaining from a synthesis gas composed of carbon monoxide and hydrogen by the Fischer-Tropsch method, and any of those obtained by any of the methods can be used.

Next, the polypropylene wax (B) used in the present invention will be described.

The polypropylene wax (B) used in the present invention has a content of 1 to 30 mgKOH / g, preferably
It has an acid value of 1 to 15 mgKOH / g.

If the acid value is less than 1 mgKOH / g, the effect of the acid cannot be sufficiently exerted. In addition, the acid value is 30 mg KO
If it exceeds H / g, it is liable to be affected by environmental humidity, and it is difficult to obtain stable charging performance, which is not preferable.

As the polypropylene wax,
Examples include a homopolymer of propylene and a copolymer of propylene and another olefin (particularly, ethylene is preferable).
The propylene copolymer needs to have a propylene component of 60% by weight or more.

As the acid monomer used for modifying the polypropylene wax, those containing at least one of a carboxyl group, a carboxylic acid anhydride group and a carboxylic acid group are preferable. For example, acrylic acid, methacrylic acid, α- There are acrylic acid such as ethylacrylic acid and crotonic acid and its α- or β-alkyl derivative, unsaturated dicarboxylic acid such as fumaric acid, maleic acid and citraconic acid and its monoester derivative or anhydride, and the like. Can be used alone or as a mixture.

Among them, a polypropylene wax modified with an acid monomer selected from at least one of maleic acid, maleic acid half ester and maleic anhydride is preferable. Further, an unmodified polypropylene wax may be mixed and used.

DSC of polypropylene wax (B)
The endothermic main peak measured by
It is preferable that the temperature is in the range of 0 ° C. and higher than the endothermic main peak of the wax (A) additionally contained.

When the polypropylene wax (B) has an endothermic main peak at a lower temperature than the endothermic main peak of the wax (A), the effect of releasing the roller from the roller at a high temperature may be deteriorated.

If the heat absorption main peak of the polypropylene wax (B) is less than 100 ° C., the offset resistance may be deteriorated. If it exceeds 170 ° C., the fixing performance is adversely affected.

The propylene wax (B) is a binder resin 1
It is preferable to use 0.5 to 20 parts by weight with respect to 00 parts by weight.

When the amount of the propylene wax (B) added is 2
When the amount is more than 0 parts by weight, the chargeability of the toner is deteriorated. If the amount is less than 0.5 part by weight, the effect of the wax cannot be obtained.

The ratio of the polypropylene wax (B) having this acid value to the wax (A) is such that the content of the wax (A) is 1 to 30% by weight of the content of the polypropylene wax (B). Preferably, there is. 1% by weight
If the amount is less than 30%, the desirable effects of the wax (A) are hardly exhibited. If the amount is more than 30% by weight, the dispersion state of the wax (A) is deteriorated, which may adversely affect electrophotographic properties such as charging performance. That's why.

Examples of the type of the binder resin used in the present invention include styrene such as polystyrene, poly-p-chlorostyrene and polyvinyltoluene, and homopolymers of substituted styrenes;
Styrene-p-chlorostyrene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-acrylate copolymer, styrene-methacrylate copolymer, styrene-α-
Chloromethyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-vinyl methyl ether copolymer, styrene-vinyl ethyl ether copolymer,
Styrene-based copolymers such as styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile-indene copolymer; polyvinyl chloride, phenolic resin, and naturally modified phenolic resin , Natural resin modified maleic resin,
Acrylic resin, methacrylic resin, polyvinyl acetate, silicone resin, polyester resin, polyurethane, polyamide resin, furan resin, epoxy resin, xylene resin, polyvinyl butyral, terpene resin, coumarone indene resin, petroleum resin, etc. can be used. Further, a crosslinked styrene resin is also a preferable binder resin.

As comonomers for the styrene monomer of the styrene copolymer, acrylic acid, methyl acrylate, butyl acrylate, dodecyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, phenyl acrylate, methacrylic acid, methacrylic acid Methyl acid,
Ethyl methacrylate, butyl methacrylate, octyl methacrylate, acrylonitrile, methacrylonitrile,
Monocarboxylic acid having a double bond such as acrylamide or a substituted product thereof; dicarboxylic acid having a double bond such as maleic acid, butyl maleate, methyl maleate, dimethyl maleate and the like; Vinyl esters such as vinyl, vinyl acetate, vinyl benzoate, etc .; ethylene olefins such as ethylene, propylene, butylene, etc .; vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone; vinyl methyl ether, vinyl ethyl Vinyl ethers such as ether and vinyl isobutyl ether are used alone or in combination. Here, as the cross-linking agent, a compound having two or more polymerizable double bonds is mainly used. For example, aromatic divinyl compounds such as divinylbenzene, divinylnaphthalene, etc .; ethylene glycol diacrylate, ethylene glycol dimethacrylate Carboxylic acid esters having two double bonds such as 1,3-butanediol dimethacrylate; divinylaniline, divinyl ether, divinyl sulfide,
A divinyl compound such as divinyl sulfone, and a compound having three or more vinyl groups can be used alone or as a mixture.

In the present invention, it is preferable that the binder resin contains substantially no component insoluble in tetrahydrofuran (THF). Specifically, the content is 5% by weight or less, preferably 3% by weight or less based on the polymer component.

The THF-insoluble content indicates a weight ratio of a polymer component (substantially a crosslinked polymer) insoluble in a THF solvent of the binder resin, and is a parameter indicating a degree of crosslinking of the binder resin containing the crosslinkable component. Can be used as
The THF-insoluble matter is defined by a value measured as follows.

0.5 to 1.0 g of the toner sample was weighed (W ₁ g), and the sample was filtered with a cylindrical filter paper (for example, No. 86 manufactured by Toyo Filter Paper Co., Ltd.)
R) and run through a Soxhlet extractor, where T
After extracting with 100 to 200 ml of HF for 6 hours and evaporating the soluble component extracted with the solvent, 10
After vacuum drying for several hours at 0 ° C., the amount of the THF-soluble resin component is weighed (W ₂ g). The weight of the components other than the resin components such as the magnetic substance, pigment and wax in the toner is defined as (W ₃ g).
The THF-insoluble content is obtained from the following equation.

THF insoluble matter (%) = [｛W ₁ − (W ₃ +
W ₂ )｝ / (W ₁ -W ₃ )] × 100 When the THF-insoluble content exceeds 5% by weight, the low-temperature fixability decreases.

The chromatogram of gel permeation chromatography (GPC) measured by the THF-soluble matter of the binder resin is at least a molecular weight of 3 × 10 ^{3 to} 3 × 1.
0 ⁴ (more preferably, 5 × 10 ³ to 2 × 10 ⁴ ), and has a main peak and a molecular weight of 1 × 10 ^{5 to} 3
× 10 ⁶ (more preferably, 5 × 10 ⁵ to 1 × 10 ⁶ )
It is preferable to have a subpeak or a shoulder in the region.

If the molecular weight of the main peak is less than 3 × 10 ^3, it tends to adhere to the pressure roller of the fixing device, which is not preferable. If the molecular weight exceeds 3 × 10 ⁴ , the fixing property is adversely affected, or There is a possibility that the dispersion of the two types of waxes used in the present invention may be hindered.

Further, by having a sub-peak or a shoulder in a molecular weight range of 1 × 10 ^{5 to} 3 × 10 ⁶ , the anti-offset performance of the toner is improved and a proper viscosity is generated in the toner. Each type of wax can be effectively dispersed.

In the present invention, the molecular weight distribution of the binder resin is measured by GPC under the following conditions.

Conditions for GPC measurement of binder resin : GPC-150C (manufactured by Waters) Column: KF801 to 807 (manufactured by Shodex) Temperature: 40 ° C. Solvent: THF (tetrahydrofuran) Flow rate: 1.0 ml / Min. Sample: 0.1 ml of a sample having a concentration of 0.05 to 0.6% by weight
Injection

The binder resin used in the present invention preferably has an acid value of 0.5 to 50 mgKOH / g.
This is because the two types of waxes used in the present invention can be effectively dispersed, respectively, to prevent the toner from adhering to the pressure roller of the fixing device.

When the acid value is less than 0.5 mgKOH / g, it is difficult to obtain this effect, and when the acid value exceeds 50 mgKOH / g, it is easily affected by environmental humidity.

As the binder resin used for obtaining the above acid value, a polymer containing at least one of a carboxyl group, a carboxylic anhydride group and a carboxylate group is most preferred. For example, acrylic acid, methacrylic acid,
There are acrylic acid such as α-ethylacrylic acid and crotonic acid and α- or β-alkyl derivatives thereof, fumaric acid, maleic acid, unsaturated dicarboxylic acids such as citraconic acid and monoester derivatives or anhydrides thereof. The desired polymer is obtained by copolymerizing such monomers alone or in combination with other monomers.

Among these, particularly preferred monomer components include maleic acid, maleic acid half ester or maleic anhydride. Since maleic acid has a carboxyl group adjacent thereto, it is suitable for more efficiently deriving the effect of the acid group, increasing affinity with a transfer material such as paper, and dispersing an acid-modified wax.

The binder resin used includes the acid value (A _VL ) of the low molecular weight polymer component (region having a molecular weight of less than 5 × 10 ⁴ in the GPC chromatogram) and the high molecular weight polymer component (GPC
Region with a molecular weight of 5 × 10 ⁴ or more in the chromatogram)
It is preferred that the acid value (A _VH) and satisfies the following condition A _VL> A _VH.

When the acid value of the polymer component is A _VL > A _VH , the wax having an acid value acts more on the low molecular weight polymer component than on the high molecular weight polymer component, and the low temperature fixation is achieved by its plastic effect. On the other hand, the wax (A) is dispersed in the binder with a certain dispersion diameter, so that the preferable releasability from the fixing roller can be exhibited more effectively.

The low molecular weight polymer component of the binder resin has an acid value of 10 to 35 mg KOH / g, and the high molecular weight polymer has an acid value of 0.5 to 11 mg KOH / g. It is preferable to be within the range of 3 ≦ (A _VL −A _VH ) ≦ 27.

The low-temperature fixability is determined by the Tg of the low molecular weight polymer component.
And the molecular weight distribution, but by including an acid component in this component, and further increasing the acid value of the low molecular weight polymer component by 3 mgKOH / g or more than the acid value of the high molecular weight polymer component, Lower viscosity.

This is because the acid value of the high molecular weight polymer component is set to be lower than the acid value of the low molecular weight polymer component by 3 mgKOH / g or more, so that the low molecular weight polymer component, the high molecular weight polymer component and the present invention can be used. The entanglement of the molecular chains of the two types of waxes to some extent, lower the viscosity at low temperatures,
Since the elastic properties are maintained on the high-temperature side and the wax is present in the toner particles with a certain domain diameter, a sufficient releasing effect is obtained, and the low-temperature fixability and the developing characteristics in a high-speed machine are improved.

On the other hand, the difference in acid value is 27 mgKOH / g
If the ratio exceeds the above range, problems will occur in the mixing properties of the low molecular weight polymer component and the high molecular weight polymer component and in the dispersibility of the wax component, particularly the wax (A), and the offset resistance and the developability will decrease.

Further, the acid value of the low molecular weight polymer component is 10 m
In the case of gKOH / g or more, the rising property of charging becomes good and the acid value of the low molecular weight polymer component is 35 mgKOH / g.
If it exceeds g, the developability under high humidity will decrease.

The acid value of the high molecular weight polymer component is 0.5 mgK
If it is less than OH / g, the miscibility with the low molecular weight polymer component and the polypropylene wax (B) having an acid value becomes defective, the offset resistance is reduced, and fogging is liable to occur.

_Regarding the relationship between the acid value of the polymer component and the acid value (A _VWAX ) of the polypropylene wax, the wax preferably satisfies the following conditions.

A _VL > A _VWAX

By controlling the compatibility between the wax and the binder resin, especially the low-molecular-weight polymer, the low-temperature fixability and the offset resistance can be remarkably improved, and the acid value of the polypropylene-based wax component is reduced to the low-molecular weight. As long as the above conditions are satisfied with respect to the acid value of the united component, the fluidity and charge stability of the toner are improved.

When the acid value of the wax is A _VL ≦ A _VWAX with respect to the acid value of the low molecular weight polymer component, the offset resistance and the toner chargeability under high humidity are reduced.

More preferably, the acid value of the wax satisfies the following condition with respect to the acid value of the low molecular weight polymer component.

0.5 × A _VL > A _VWAX > 0.05 × A _VL

In the present invention, the acid value of the low molecular weight polymer component and the high molecular weight polymer component of the toner polymer component is determined by the following method.

Separation device configuration of each component LC-908 (Nippon Kagaku Kogyo Co., Ltd.) JRS-86 (company; repeat injector) JAR-2 (company; autosampler) FC-201 (Gilson; fraction collector) Column configuration JAIGEL-1H to 5H (diameter 20mm x length 600
mm: preparative column) Measurement conditions Temperature: 40 ° C. Solvent: THF Flow rate: 5 ml / min. Detector: RI (refractive index) detector

In the sample, additives other than the binder resin are separated in advance. As a fractionation method, an elution time at which the molecular weight becomes 5 × 10 ⁴ is measured in advance, and before and after the elution time, a low molecular weight polymer component and a high molecular weight polymer component are fractionated. The solvent is removed from the sampled sample to obtain an acid value measurement sample.

Measurement of Acid Value 1) A crushed sample of 0.1 to 0.2 g is precisely weighed, and its weight is defined as W (g).

2) Put the sample in a 20 cc Erlenmeyer flask,
10 cc of a mixed solution of toluene / ethanol (2: 1) is added and dissolved.

3) Add a few drops of an alcohol solution of phenolphthalein as an indicator.

4) Using a burette, 0.1 KO
The solution in the flask is titrated with an alcoholic solution of H. The amount of the KOH solution dropped at this time is defined as S (ml). At the same time, a blank state is performed, and the drop amount of the KOH solution is
(Ml).

5) Calculate the acid value by the following equation.

Acid value = (S−B) × f × 5.61 / W
(F: KOH factor)

The electrostatic image developing toner of the present invention preferably uses an organometallic compound as a charge control agent.
In particular, those containing an organic compound rich in vaporization and sublimation as a ligand and a counter ion are useful. As such a metal complex, a metal complex type monoazo compound is preferably used from the viewpoint of chargeability. Examples of metal complex type monoazo compounds include JP-B-41-20153 and JP-B-42-2.
7596, 44-6397 and 45-2
No. 6478, etc., and in the present invention, a metal complex type monoazo compound represented by the following general formula (I) is preferred from the viewpoint of dispersibility and chargeability.

[0077]

[Outside 1] [Wherein, M represents a coordination center metal, and Cr, Co, Ni,
Mn, Fe, Ti, Al and the like can be used. Ar
Is an aryl group, such as a phenyl group and a naphthyl group, and may have a substituent. The substituent in this case is a nitro group, a halogen group, a carboxy group, an anilide group, an alkyl group having 1 to 18 carbon atoms, or an alkoxyl group. X, X ', Y, Y' are -O-, -CO-, -N
H-, -NR- (R is an alkyl group having 1 to 4 carbon atoms).

[0078]

[Outside 2] Represents a hydrogen ion, a sodium ion, a potassium ion, an ammonium ion or an aliphatic ammonium ion].

Among them, it is preferable to use a metal complex type monoazo iron complex in which the central metal is iron. More preferably, a monoazo iron complex represented by the following general formula (II) is used.

[0080]

[Outside 3] [Wherein X ₁ and X ₂ represent a hydrogen atom, a lower alkyl group, a lower alkoxy group, a nitro group or a halogen atom,
And m 'is a hydrogen atom Y ₁ and Y ₃ represents an integer of 1 to 3, alkyl of C ₁ -C _18, alkenyl of C ₂ -C _18, sulfonamide, mesyl, sulfonic acid, carboxy ester, hydroxy, C ₁ -C ₁₈ alkoxy, acetylamino, benzoyl, an amino group or a halogen atom, n and n 'represents an integer of 1 to 3, Y ₂ and Y
₄ represents a hydrogen atom or a nitro group, (above X ₁ and X
_2, m and m ', Y ₁ and Y _3, n and n', Y ₂ and Y ₄ may be the same or different. )

[0081]

[Outside 4] Represents an ammonium ion, an alkali metal ion, a hydrogen ion or a mixture thereof. ]

The content of the metal complex type monoazo compound is preferably from 0.5 to 5 parts by weight, particularly preferably from 0.2 to 3 parts by weight, based on 100 parts by weight of the binder resin. If the content of the metal complex type monoazo compound is too large, the fluidity of the toner deteriorates and fogging tends to occur, while if it is too small, it is difficult to obtain a sufficient charge amount.

The electrostatic image developing toner of the present invention is preferably used as a toner containing a magnetic material.
Examples of magnetic materials that can be used include metal oxides containing elements such as iron, cobalt, nickel, copper, magnesium, manganese, aluminum, and silicon. These magnetic particles is preferably a BET specific surface area by the nitrogen adsorption method 1-20 m ² / g, especially 2.5~12m ² / g, further Mohs hardness magnetic powder 5-7 is preferred. Examples of the shape of the magnetic body include an octahedron, a hexahedron, a sphere, a needle, and a scaly shape, and an octahedron, a hexahedron, and a sphere having little anisotropy are preferable. This is because those having an isotropic shape can achieve good dispersion even in a binder resin or wax as in the present invention. The average particle size of the magnetic material is preferably 0.05 to 1.0 μm, more preferably 0.1 to 0.6 μm, and further preferably 0.1 to 0.4 μm.
Is preferred. The magnetic material is preferably added in an amount of 60 to 200 parts by weight based on 100 parts by weight of the toner binder resin.
Particularly preferably, it is 70 to 150 parts by weight. If the amount is less than 60 parts by weight, the transportability of the toner at the time of development becomes insufficient, and the developer layer on the developer carrier becomes uneven, resulting in image unevenness. Further, the image density tends to decrease due to an excessive increase in the charge of the developer. If the amount exceeds 200 parts by weight, sufficient charge of the developer cannot be obtained, so that the image density is reduced.

The toner of the present invention has environmental stability,
In order to improve charge stability, developability, fluidity and storage stability, it is preferable that inorganic fine powder or hydrophobic inorganic fine powder is mixed. For example, fine silica powder, fine titanium oxide powder, or a hydrophobized product thereof may be used. They can be used alone or in combination.

As the fine silica powder, both a so-called dry method produced by the vapor phase oxidation of a silicon halide or a so-called fumed silica, and a so-called wet silica produced from water glass or the like can be used. But,
Surface and having less silanol groups inside, also Na ₂
Dry silica with less production residues such as O and SO ₃ ^2- is more preferable. In the case of fumed silica, it is also possible to obtain a composite fine powder of silica and another metal oxide by using another metal halide such as aluminum chloride and titanium chloride together with a silicon halide in the production process. They can also be used.

Further, the silica fine powder is preferably subjected to a hydrophobic treatment. The hydrophobized silica fine powder can be obtained by chemically treating the silica fine powder with an organic silicon compound or the like which reacts or physically adsorbs the silica fine powder. As a preferable method, a method of treating a dry silica fine powder produced by vapor phase oxidation of a silicon halide compound with a silane coupling agent or treating with a silane coupling agent and simultaneously treating with an organosilicon compound such as silicone oil. Is mentioned.

Examples of the silane coupling agent used in the hydrophobic treatment include hexamethyldisilazane, trimethylsilane, trimethylchlorosilane, trimethylethoxysilane, dimethyldichlorosilane, methyltrichlorosilane, allyldimethylchlorosilane, and allylphenyl. Dichlorosilane, benzyldimethylchlorosilane, bromomethyldimethylchlorosilane, α-chloroethyltrichlorosilane, β-chloroethyltrichlorosilane,
Chloromethyldimethylchlorosilane, triorganosilylmercaptan, trimethylsilylmercaptan, triorganosilyl acrylate, vinyldimethylacetoxysilane, dimethyldiethoxysilane, dimethyldimethoxysilane, diphenyldiethoxysilane, hexamethyldisiloxane, 1,3-divinyltetramethyl Disiloxane, 1,3-diphenyltetramethyldisiloxane and dimethylpolysiloxane having 2 to 12 siloxane units per molecule and having hydroxyl groups bonded to silicon atoms at each terminal unit, one for each terminal unit, etc. Is mentioned.

Examples of the organosilicon compound include silicone oil. Preferred silicone oils are those having a viscosity of 30 to 1000 centistokes at 25 ° C., such as dimethyl silicone oil, methylphenyl silicone oil, α-methylstyrene-modified silicone oil, chlorophenyl silicone oil, and fluorine-modified silicone. Oil and the like are particularly preferred.

As a method of treating silicone oil, for example, silica fine powder treated with a silane coupling agent and silicone oil may be directly mixed using a mixer such as a Henschel mixer, or silica fine powder serving as a base may be mixed. A method of spraying silicone oil on the body may be used.
Alternatively, a method of dissolving or dispersing a silicone oil in an appropriate solvent, adding a silica fine powder, mixing and removing the solvent may be used.

If necessary, an external additive other than silica fine powder or titanium oxide fine powder may be added to the electrostatic image developing toner of the present invention.

For example, there are resin fine powder and inorganic fine particles which function as a charge auxiliary agent, a conductivity-imparting agent, a fluidity-imparting agent, a caking preventing agent, a releasing agent at the time of fixing with a hot roll, a lubricant, an abrasive and the like.

For example, lubricants such as Teflon, zinc stearate and polyvinylidene fluoride, among which polyvinylidene fluoride are preferred. Alternatively, abrasives such as cerium oxide, silicon carbide, and strontium titanate, among which strontium titanate, are preferred. Alternatively, for example, a fluidity-imparting agent such as titanium oxide and aluminum oxide, particularly a hydrophobic agent is preferable. An anti-caking agent or a conductivity-imparting agent such as, for example, carbon black, zinc oxide, antimony oxide, or tin oxide, or white and black fine particles of opposite polarity can be used in a small amount as a developability improver.

The fine resin particles or fine inorganic particles mixed with the toner are added in an amount of 0.1 to 100 parts by weight of the magnetic toner.
To 5 parts by weight (preferably 0.1 to 3 parts by weight).

The toner for developing an electrostatic image of the present invention is prepared by thoroughly mixing the toner constituting materials with a mixer such as a ball mill, and then melting, kneading and kneading the mixture using a hot kneader such as a heating roll, a kneader or an extruder. It can be produced by grinding and then crushing and strict classification after solidification.

[0095]

EXAMPLES The present invention will be described below with reference to specific examples, but the present invention is not limited to these examples.

Example 1 As a low molecular weight polymer, styrene-butyl acrylate synthesized by a known method was used.
Monobutyl maleate copolymer (L1) (peak molecular weight 10700, acid value 30 mgKOH / g) was used as a high molecular weight polymer, and styrene-butyl acrylate-monobutyl maleate copolymer (H1) (peak molecular weight 1.03 million and an acid value of 7 mgKOH / g). After dissolving 70 parts by weight of the low molecular weight polymer (L1) and 30 parts by weight of the high molecular weight polymer (H1) in 100 parts by weight of reflux xylene, the organic solvent is distilled off, and the obtained resin is cooled. After solidification, it was pulverized to obtain a resin raw material for toner.

100 parts by weight of the above resin material for toner,
100 parts by weight of spherical magnetic iron oxide, 2 parts by weight of the following metal complex type monoazo compound, propylene-ethylene copolymer (B1) modified with maleic anhydride (95% propylene component)
・ Acid value 4.3mgKOH / g ・ DSC peak 135 ° C)
8 parts by weight and polyethylene wax (A1) (DSC
0.8 parts by weight (peak 101 ° C., half width 10 ° C.) were uniformly mixed in advance, and the mixture was melt-kneaded with a twin-screw extruder heated to 130 ° C. After cooling this kneaded material, coarsely pulverized with a hammer mill, and further finely pulverized with a jet mill,
The obtained pulverized product was subjected to air classification, and the weight average diameter D _{4 was} 6.9 μm.
m of toner particles were obtained.

[0098]

[Outside 5]

To 100 parts by weight of the toner particles, 1.5 parts by weight of hydrophobized silica fine powder was dry-mixed and externally added to obtain a toner (T1).

Table 1 shows the result of analyzing the toner (T1).
It writes in.

Example 2 Unmodified polypropylene wax (propylene component: 99% or more; DSC peak: 137)
° C), 3 parts by weight of the maleic anhydride-modified polypropylene wax (B1), and 1 part by weight of the polyethylene wax (A1) in the same manner as in Example 1 to obtain a toner (T2). .

Table 1 shows the result of analyzing the toner (T2).
It writes in.

Example 3 Polyethylene Wax (A
Instead of 1), polyethylene wax (A2) (DS
A toner (T3) was obtained in the same manner as in Example 1 except that 1.5 parts by weight of the C peak (65 ° C./half width at 18 ° C.) was used.

Table 1 shows the result of analyzing the toner (T3).
It writes in.

Example 4 Polyethylene Wax (A
Instead of polyethylene wax (A3) (DS)
A toner (T4) was obtained in the same manner as in Example 1 except that 1.5 parts by weight of the C peak at 125 ° C. and the half width at 13 ° C. was used.

Table 1 shows the result of analyzing the toner (T4).
It writes in.

Example 5 Instead of the maleic anhydride-modified polypropylene wax (B1), a polypropylene wax similarly modified with maleic anhydride (B2)
(Propylene component 96%, acid value 15mgKOH / gD
SC peak 142 ° C), 6 parts by weight, polyethylene wax (A4) instead of polyethylene wax (A1)
A toner (T5) was obtained in the same manner as in Example 1, except that 1 part by weight (DSC peak 99 ° C., half width 15 ° C.) was used.

Table 1 shows the result of analyzing the toner (T5).
It writes in.

Example 6 As a low molecular weight polymer, a styrene-butyl acrylate-acrylic acid copolymer (L2)
(T6) was obtained in the same manner as in Example 1 except that (peak molecular weight: 8,000, acid value: 27 mgKOH / g).

Table 1 shows the result of analyzing the toner (T6).
It writes in.

Example 7 Polyethylene Wax (A
Paraffin wax (A5) (DSC)
A toner (T7) was obtained in the same manner as in Example 1 except that 1 part by weight of a peak at 68 ° C. and a half width at 11 ° C.) was used.

Table 1 shows the result of analyzing the toner (T7).
It writes in.

Example 8 As a low molecular weight polymer, a styrene-butyl acrylate-monobutyl maleate copolymer (L3) (peak molecular weight 9900, acid value 9.1 mgK)
OH / g), to obtain a toner (T8) in the same manner as in Example 5.

Table 1 shows the result of analyzing the toner (T8).
It writes in.

Example 9 As a low molecular weight polymer, styrene-butyl acrylate-monobutyl maleate copolymer (L4) (peak molecular weight 15000, acid value 2 mg KO)
H / g), to obtain a toner (T9) in the same manner as in Example 1.

Table 1 shows the result of analyzing the toner (T9).
It writes in.

Example 10 As a low molecular weight polymer, a styrene-butyl acrylate-acrylic acid copolymer (L
5) (Peak molecular weight 9000, acid value 0 mgKOH / g)
Styrene-butyl acrylate copolymer (H2) (peak molecular weight 900,000, acid value 0
mgKOH / g), to obtain a toner (T10) in the same manner as in Example 1.

Table 1 shows the result of analyzing the toner (T10).

Example 11 As a low molecular weight polymer, a styrene-butyl acrylate-monobutyl maleate copolymer (L6) (peak molecular weight 2800, acid value 20 mgK
OH / g) to obtain a toner (T11) in the same manner as in Example 5.

Table 1 shows the result of analyzing the toner (T11).

Example 12 Polyethylene Wax (A
In the same manner as in Example 1 except that paraffin wax (A2) was used in an amount of 3 parts by weight instead of 1), toner (T1
2) was obtained.

Table 1 shows the result of analyzing the toner (T12).

Example 13 Instead of the maleic anhydride-modified polypropylene wax (B1), a methacrylic acid-modified polypropylene wax (B3) (propylene component%, acid value 2.0 mg KOH / g, DSC peak 12)
(0 ° C.) except that 6 parts by weight was used.
Thus, a toner (T13) was obtained.

Table 1 shows the result of analyzing the toner (T13).

(Example 14) Polyethylene wax (A
A toner (T14) was obtained in the same manner as in Example 1, except that the amount of 1) was changed to 2 parts by weight and the amount of the maleic anhydride-modified polypropylene wax (B1) was changed to 7 parts by weight.

Table 1 shows the result of analyzing the toner (T14).

Comparative Example 1 A toner (T15) was obtained in the same manner as in Example 6 except that only 4 parts by weight of the polypropylene wax (C1) (DSC peak 135 ° C.) was used as the wax.

Table 2 shows the result of analyzing the toner (T15).

Comparative Example 2 Toner (T1) was prepared in the same manner as in Example 6 except that only 4 parts by weight of polyethylene wax (C2) (DSC peak 89 ° C.) was used as the wax.
6) was obtained.

Table 2 shows the result of analyzing the toner (T16).

Comparative Example 3 A toner (T1) was prepared in the same manner as in Example 1 except that only 7 parts by weight of the maleic anhydride-modified polypropylene wax (B1) was used as the wax.
7) was obtained.

Table 2 shows the result of analyzing the toner (T17).

Comparative Example 4 Toner was prepared in the same manner as in Example 1 except that only 7 parts by weight of maleic anhydride-modified polyethylene wax (C3) (DSC peak 97 ° C., acid value 8 mg KOH / g) was used as the wax. (T18) was obtained.

Table 2 shows the result of analyzing the toner (T18).

Comparative Example 5 A toner (T19) was prepared in the same manner as in Example 6 except that 3 parts by weight of the polypropylene wax (C1) and 3 parts by weight of the maleic anhydride-modified polypropylene wax (B1) were used as the wax. ) Got.

Table 2 shows the result of analyzing the toner (T19).

Comparative Example 6 A toner (T20) was prepared in the same manner as in Example 6 except that 3 parts by weight of a polypropylene wax (C1) and 3 parts by weight of a maleic anhydride-modified polyethylene wax (C3) were used as waxes. ) Got.

Table 2 shows the result of analyzing the toner (T20).

Comparative Example 7 Polyethylene Wax (A
Paraffin wax (A6) (DSC)
A toner (T21) was obtained in the same manner as in Example 1 except that 1 part by weight of the toner (peak 45 ° C) was used.

Table 2 shows the result of analyzing the toner (T21).

(Comparative Example 8) Polyethylene wax (A
Instead of 1), polyethylene wax (A7) (DS
A toner (T22) was obtained in the same manner as in Example 7, except that 1 part by weight of C peak (133 ° C.) was used.

Table 2 shows the result of analyzing the toner (T22).

(Comparative Example 9) Instead of the maleic anhydride-modified polypropylene wax (B1), a maleic anhydride-modified polypropylene wax (B4) (propylene component 97%, acid value 0.5 mg KOH / g, DSC peak 133 C.) was used in the same manner as in Example 1 except that 6 parts by weight of the toner (T23) was used.

Table 2 shows the result of analyzing the toner (T23).

(Comparative Example 10) Instead of the maleic anhydride-modified polypropylene wax (B1), a maleic anhydride-modified polypropylene wax (B5) (propylene component 97%, acid value 43 mg KOH / g, DSC peak 128 ° C) Was used in the same manner as in Example 1 except that 6 parts by weight of was used, to obtain a toner (T24).

Table 2 shows the result of analyzing the toner (T24).

(Comparative Example 11) Polyethylene wax (A
Instead of polyethylene wax (A8) (DS)
A toner (T25) was obtained in the same manner as in Example 1 except that 1 part by weight of the C peak (130 ° C., half width at 35 ° C.) was used.

Table 2 shows the result of analyzing the toner (T25).

(Comparative Example 12) Polyethylene wax (A
Instead of polyethylene wax (A9) (DS)
C peak 95 ° C, half width 23.5 ° C) 1.5 parts by weight,
Maleic anhydride-modified polypropylene wax (B1)
(T26) was obtained in the same manner as in Example 1 except that the amount of was changed to 6 parts by weight.

Table 2 shows the result of analyzing the toner (T26).

[0151]

[Table 1]

[0152]

[Table 2]

(Evaluation) Evaluation was performed using the toner thus obtained. The printout test, fixability and offset resistance test were performed as follows.

<Print-out test> Normal temperature and normal humidity (25 ° C.)
・ 60% RH, high temperature and high humidity (32.5 ℃ ・ 80% R)
H) and a commercially available laser beam printer LBP-930 in each environment of low temperature and low humidity (10 ° C. and 15% RH).
(Canon) was modified into the following configuration, and a printout test was performed under the following conditions. When the toner was exhausted, a cutout was made in the toner container at the top of the cartridge, and the toner was replenished therefrom to continue the printout test. An electrostatic latent image is formed by setting the primary charge to -670 V, a gap (290 μm) is set without contact between the photosensitive drum and the developer layer on the developer carrier (magnet inclusion), and an AC bias (f = 2000 Hz; Vpp) = 1600 V) and a DC bias (Vdc = -500 V). Printout speed is 32 sheets (A4 landscape)
/ 1 minute. The obtained images were evaluated for the following items.

Image Density Evaluation was made by maintaining the image density at the end of printing out 20,000 sheets on ordinary paper for copying machines (75 g / m ² ).
The image density was measured by using a "Macbeth reflection densitometer" (manufactured by Macbeth Co., Ltd.) with respect to a printout image of a white background portion having a document density of 0.00.

The whiteness of the transfer paper measured by a fog reflectometer (manufactured by Tokyo Denshoku Co., Ltd.) and low temperature and low humidity (10 ° C., 15% RH)
Under the environment, fog was calculated by comparing the solid white after 5,000 sheets of endurance images had been printed with the whiteness of the transfer paper after printing.

Fixing Property The fixing property is 1 in a low temperature and low humidity (10 ° C., 15% RH) environment.
50 g / cm ^{2 on} the image at the end of the 00 printout
Was applied, and the fixed image was rubbed with a soft thin paper, and the reduction in image density before and after rubbing (%) was evaluated. Plain paper for copiers (90 g /
m ² ) was used.

A: less than 5% B: 5 to 10% C: 10 to 20% D: more than 20%

Offset Resistance The offset resistance is determined by printing out a sample image having an image area ratio of about 5% after printing 1,000 sheets in an environment of normal temperature and normal humidity (25 ° C., 60% RH), and removing the stain on the image. Was evaluated according to the degree of Plain paper for copying machines (64 g / m ² ) was used as test paper.

A: not generated B: hardly generated C: small amount of dirt generated D: dirt generated

Degree of adhesion of toner and paper powder to the pressure roller of the fixing device In a low-temperature and low-humidity environment (10 ° C., 15% RH), the pressure of the pressure roller was adjusted to 30 kg, and calcium carbonate was used as a filler. Weight percent of plain paper for copiers (80 g / m
² ) After 500,000 images were printed, the surface of the pressure roller of the fixing device was visually observed, and the degree of adhesion of toner and paper powder to the roller was evaluated.

A: not generated B: hardly generated C: toner and paper powder adhered only to the end D: toner
Paper powder adhesion

Degree of adhesion of toner and paper powder to fixing roller heating roller Plain paper for copying machine (80 g) containing 15% by weight of calcium carbonate as a filler in a low temperature and low humidity (10 ° C., 15% RH) environment
/ M ² ), the surface of the fixing device heating roller was visually observed, and the degree of adhesion of toner and paper powder to the roller was evaluated.

A: Not generated B: Almost not generated C: Toner / paper powder adhered only to the end D:
Paper powder adhesion

By the above evaluation methods, Examples 1 to 14,
In addition, the toners of Comparative Examples 1 to 12 were evaluated. The results are summarized in Tables 3 and 4.

[0166]

[Table 3]

[0167]

[Table 4]

[0168]

As described above, the toner of the present invention can maintain a high developing property even under various environments, and can highly satisfy the fixing property and the anti-offset property. It is a highly durable toner that is highly applicable to highly durable electrophotographic processes in which toner and components derived from paper powder do not adhere to or adhere to paper.

Claims (12)

[Claims] 1. An electrostatic image developing toner having at least a binder resin and a wax, wherein the wax has an endothermic main peak measured by a differential scanning calorimeter (DSC) at 50 to 130 ° C. A toner for developing an electrostatic charge image, comprising: a wax (A) having a half width of a main peak of 20 ° C. or less and a polypropylene wax (B) having an acid value of 1 to 30 mgKOH / g. 2. The polypropylene wax (B) having an acid value is a polypropylene wax modified with an acid monomer selected from at least one of maleic acid, maleic acid half ester and maleic anhydride. The toner for developing an electrostatic image according to claim 1, wherein: 3. The electrostatic image developing toner according to claim 1, wherein the wax (A) is a polyethylene wax. 4. The method according to claim 1, wherein the content of the polypropylene wax (B) is 0.5 to 20 parts by weight based on 100 parts by weight of the binder resin. The toner for developing an electrostatic image according to the above. 5. The method according to claim 1, wherein the content of the wax (A) is 1 to 30% by weight of the content of the polypropylene wax (B). Charge image developing toner. 6. The D of the polypropylene wax (B)
The endothermic main peak measured by SC is 100 to 1
The electrostatic charge according to any one of claims 1 to 5, wherein the electrostatic charge is in the range of 70 ° C and higher than the endothermic main peak measured by DSC of the wax (A) additionally contained. Image developing toner. 7. The binder resin contains substantially no THF-insoluble matter and has a molecular weight of at least 3 × 10 ^{3 in} GPC (gel permeation chromatogram) of a THF-soluble matter.
Has a main peak in the region of to 3 × 10 ^4, and static according to claim 1, characterized in that it comprises a sub-peak or shoulder in a molecular weight region of 1 × 10 ⁵ ~3 × 10 ⁶ Charge image developing toner. 8. The method according to claim 1, wherein the binder resin is 0.5 to 50 mg KO.
The electrostatic image developing toner according to claim 7, wherein the toner has an acid value of H / g. 9. The method according to claim 1, wherein the binder resin is a low molecular weight polymer (GPC).
(Molecular weight of less than 5 × 10 ⁴ ) (A _VL )
9. The static electricity according to claim 7, wherein the acid value (A _VH ) of the polymer and the high molecular weight polymer (region having a molecular weight of 5 × 10 ⁴ or more in GPC) satisfies A _VL > A _VH. Charge image developing toner. 10. An acid component of the binder resin is maleic acid,
The toner for developing an electrostatic image according to any one of claims 7 to 9, wherein the toner is formed from an acid monomer selected from at least one of maleic acid half ester and maleic anhydride. 11. An acid value (A _VL ) of the low molecular weight polymer component of the binder resin is 10 to 35 mgKOH / g, and an acid value (A _VH ) of the high molecular weight polymer component is 0.5 to 11 mgK.
11. The toner according to claim 7, wherein OH / g is satisfied and the difference satisfies the following condition: 3 ≦ (A _VL −A _VH ) ≦ 27. 12. The acid value (A _VWAX ) of the polypropylene wax (B) is based on the following condition: 0.5 × A _VL > A _VWAX > 0.05 with _respect to the acid value (A _VL ) of the low molecular weight polymer component. × the toner according to any one of claims 7 to 11, characterized by satisfying the a _VL.