JP3392038B2 - Toner for developing electrostatic images - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrostatic charge image developing toner used in electrophotography, electrostatic recording, magnetic recording and the like, and more particularly, to fixing the formed visible image on a recording material by heating. The present invention relates to a toner for developing an electrostatic image which is used in the method.

[0002]

2. Description of the Related Art Conventionally, as an electrophotographic method, U.S. Pat. No. 2,297,691 and JP-B-42-23910 are known.
Although many methods are known as described in JP-B No. 43-24748 and Japanese Patent Publication No. 43-24748, generally, a photoconductive substance is used and an electric latent image is formed on a photoreceptor by various means. Then, the latent image is developed with toner to form a visible image, and the toner image is transferred to a transfer material such as paper as necessary, and then the toner image is fixed on the transfer material by heat or pressure. To obtain a copy. Further, the toner particles remaining on the photoconductor without being transferred onto the transfer material are removed from the photoconductor by the cleaning step, and the above steps are repeated.

In recent years, devices using electrophotography have begun to be used in printers, facsimiles, etc. for computer output in addition to conventional copying machines. For example, as for printer devices, LBP printers or LED printers have become the mainstream of the market recently, and as a direction of technology,
Previously 240, 300 dpi was 400, 60
The resolution has become higher at 0, 800, and even 1200, 2400 dpi. Therefore, the developing method is also required to have higher definition. As the performance of computers becomes higher, the output images are required to have higher definition and higher image quality. Furthermore, due to the spread of personal computers, maintenance can be performed more easily and at the same time higher. Reliability has been rigorously pursued, and accordingly, the performance required for printers has become higher, and if improved toner performance cannot be achieved, better machines cannot be established. For example, the fixing performance is the most important performance required for the toner in a digital printer and copying of high-definition images. Regarding the fixing process, various methods and devices have been developed, but the most popular method at present is a pressure heating method using a heat roller. The pressure heating method using this heating roller performs fixing by allowing the toner image surface of the sheet to be fixed to pass under pressure while contacting the surface of a heat roller whose surface is formed of a material having releasability for toner. Is. In this method, since the surface of the heat roller and the toner image on the sheet to be fixed are brought into contact with each other under pressure, the thermal efficiency at the time of fusing the toner image on the sheet to be fixed is extremely good, and quick fixing is possible. It is possible and very effective in a high speed electrophotographic copying machine.

However, the following problems are likely to occur in the above-described heat roller fixing which has been frequently used.

(1) There is a so-called wait time during which the image forming operation is prohibited until the heat roller reaches a predetermined temperature; (2) The temperature of the heat roller fluctuates due to passage of a recording material or other external factors. It is necessary to maintain the heating roller at an optimum temperature in order to prevent the fixing phenomenon due to the fixing failure and the offset phenomenon due to the transfer of the toner to the heating roller. For this purpose, the heat capacity of the heating roller or the heating body must be increased. However, this requires a large amount of electric power and causes a temperature rise inside the image forming apparatus. (3) Since the heating roller has a high temperature, when the recording material is discharged through the heating roller, The fixed image on the transfer material is cooled slowly, the toner and the fixed image have adhesiveness,
Paper jams may occur due to offset on the heating roller or winding of the transfer material.

There is a demand for a toner for realizing a fixing method that achieves a good fixing property of a toner image on a recording material and prevention of offset, and that has a short wait time and low power consumption.

To date, many studies have been made to improve toner performance. For example, in order to prevent the toner from adhering to the surface of the fixing roller, the roller surface is made of a material such as fluorine resin that has excellent releasability for the toner, and a silicone oil or other offset prevention liquid is further formed on the surface. It is practiced to coat the roller surface with a thin film of liquid supplied.

This method is extremely effective in preventing toner offset, but the offset preventing liquid is heated to generate an odor, and a device for supplying the offset preventing liquid is required. To
There is a drawback that the copying machine becomes expensive because the mechanism of the copying machine becomes complicated and high precision is required to obtain a stable result.

Various attempts have been made to improve the binder resin in the toner.

For example, a method is known in which the glass transition temperature (Tg) and the molecular weight of the binder resin in the toner are increased to improve the melt viscoelasticity of the toner. However, in such a method, when the offset phenomenon is improved, the fixability is lowered, and the fixability required for high-speed development and energy saving is lowered.

Generally, in order to improve the low temperature fixing property of the toner, it is necessary to reduce the viscosity of the toner at the time of melting to increase the adhesion area with the recording material. For this purpose, the Tg and the molecular weight of the binder resin used are It is preferable to lower it.

As described above, since the low temperature fixing property and the offset preventing property of the toner have opposite sides, it is difficult to develop a toner satisfying both of these functions.

To solve this problem, Japanese Patent Publication No.
In 23354, a cross-linking agent and a molecular weight modifier are added,
Toners made of moderately crosslinked vinyl polymers have been proposed. Japanese Patent Publication No. 55-6805 discloses that the molecular weight distribution is wide so that the ratio of the weight average molecular weight to the number average molecular weight is 3.5 to 4.0 with the α, β unsaturated ethylenic monomer as a constitutional unit. Toners have been proposed.

Certainly, these toners are between the lower limit fixing temperature (the lowest fixing temperature) and the offset temperature (the temperature at which offset starts to occur), as compared with the toner made of a single resin having a narrow molecular weight distribution. Although the feasible fixing temperature range is widened, it is difficult to sufficiently lower the fixing temperature when sufficient offset prevention performance is provided.
On the other hand, there is a problem that the offset prevention performance becomes insufficient when the low temperature fixability is emphasized.

Instead of these vinyl resins, a polyester resin which is essentially superior to vinyl resins in terms of low-temperature fixability is crosslinked, and an offset inhibitor is further added to the toner. -208559 is proposed. This toner is excellent in both low-temperature fixing property and offset prevention property, but there is a problem in toner productivity (crushability).

Further, in JP-A-56-116043, a vinyl monomer is polymerized in the presence of a reactive polyester resin and polymerized through a crosslinking reaction, an addition reaction and a grafting reaction in the course of the polymerization. A toner using a resin has been proposed. Although it is improved in terms of pulverizability, it is difficult to make full use of the functions of the resins in terms of low-temperature fixability and offset prevention.

Simply, two types of polyester resin and gel content different (gel content 80% or more and gel content 1
A toner using a resin blended with a vinyl resin of less than 0%) is proposed in Japanese Patent Publication No. 1-10663.
Although this toner has good low-temperature fixability, it needs to be further improved in terms of offset prevention and crushability. When the proportion of the vinyl resin having a gel content of 80% or more is increased for the purpose of improving the offset resistance, the offset prevention property is improved, but on the contrary, the low temperature fixing property is remarkably lowered. Further, it is difficult to obtain sufficient pulverizability of the kneaded product at the time of toner production by only adding a vinyl resin having a gel content of less than 10%.

As a binder resin, it is proposed in JP-A-57-178249 and 57-178250 to use a resin obtained by reacting a polymer having a carboxylic acid with a metal compound and crosslinking the resin. Has been done. A method of reacting a binder having a vinyl monomer and a specific monoester compound as an essential constitutional unit with a polyvalent metal compound and crosslinking the same through a metal is disclosed in JP-A-61-110155 and JP-A-61-1605. It is proposed in Japanese Patent No. 110156.

Furthermore, JP-A-63-214760, JP-A-63-217362, and JP-A-63-2.
No. 17363 and JP-A-63-217364, a carboxylic acid group having a molecular weight distribution divided into two groups, a low molecular weight region and a high molecular weight region, is reacted with a polyvalent metal ion contained on the low molecular weight side. A method of cross-linking has been proposed. In either method, the reaction between the binder resin and the metal compound or the dispersion of the metal compound in the binder resin is not sufficient, and the fixing property and offset resistance required for the toner have not been satisfied. Moreover, since it is necessary to mix a large amount of the metal compound with the binder resin, the mixed metal compound exhibits a catalytic action on the binder resin depending on the conditions, and the binder resin easily gels. As a result, the metal compound is mixed. Then, it is difficult to obtain the manufacturing conditions for obtaining the desired toner.

In adjusting the amount of acid in these toners,
It is preferable to further improve the charging characteristics (rise) of the toner, the environmental characteristics (characteristics of leaving under high humidity), and the image characteristics (fogging, density characteristics).

Further, Japanese Patent Laid-Open No. 2-168264
JP-A-2-235069 and JP-A-5-17336.
No. 3, JP-A-5-173366, JP-A-5-
Japanese Patent No. 241371 proposes a toner binder composition and a toner in which the low molecular weight component and the high molecular weight component in the binder resin are improved in molecular weight, mixing ratio, acid value and blocking resistance, and charge rising characteristics.

In the above toner, the colorant such as acidic iron oxide, the charge control agent (charge control agent), and other additives are apt to be poorly dispersed, and the surface of the developer carrying member such as the carrier or the sleeve is contaminated. Fog and image density decrease easily occur.

Japanese Unexamined Patent Publication (Kokai) No. 62-9256 proposes a binder composition for toner in which two kinds of vinyl resins having different molecular weights and acid values are blended. However, when such a binder resin is used, it is necessary to strengthen the kneading conditions in order to improve the compatibility or dispersibility of the toner constituent components. The binder resin is easily affected by the breakage of polymer molecules, and particularly, the offset resistance is likely to decrease. When kneading is performed to such an extent that polymer molecules are not cleaved, poor dispersion of the additive is likely to occur and contamination of the carrier or the surface of the developer bearing member is likely to occur. In particular, when a polymer having a weight average molecular weight of 1,000,000 or more is used, these phenomena are likely to become apparent.

JP-A-3-72505 proposes a vinyl resin having a molecular weight of 300,000 or more using a polyfunctional initiator. When such a resin is used, the fixing property can be satisfied to some extent, but the performance of the toner tends to be deteriorated when left standing in a high humidity environment. The cause of this phenomenon is not clear, but because the molecular cleavage of the binder resin is promoted during the production of the toner, the proportion of the high molecular weight resin component in the toner composition is lowered, and the heat resistance is lowered. It is speculated that there is.

On the other hand, it is known that the toner contains a low-softening point release agent (wax) such as polyolefin in order to improve low-temperature fixability and offset resistance of the toner.

Japanese Patent Laid-Open Nos. 51-14333 and 5
7-148752, JP-A-58-97056, JP-A-60-247250, and JP-A-4-36.
2953 and JP-A-6-230600 describe solid silicone varnishes, higher fatty acid waxes, higher alcohol waxes, vegetable natural waxes (carnauba, rice), montan ester waxes as release agents. There is. However, it is necessary to further improve the low temperature fixability and offset resistance of the toner, and
It is also necessary to improve the developability (chargeability) and durability of these toners.

In general, when such a low-softening point release agent is contained in the toner, the fluidity of the toner is lowered, so that the developability and transferability are lowered. In addition, the charging property, durability, and storability are likely to be adversely affected.

To solve these problems, modified waxes grafted or block-copolymerized with various monomers have been proposed.

In Japanese Patent Laid-Open No. 59-121052, α
It has been proposed to use a polyolefin graft / block copolymerized with a methylene aliphatic monocarboxylic acid ester monomer, which is disclosed in JP-A-56-15470, JP-A-59-121053, and JP-A-60-9.
In Japanese Patent No. 3456 and Japanese Patent Laid-Open No. 34550/1988, it is proposed to use a polyolefin graft / block copolymerized with an aromatic vinyl monomer. Although these toners are improved in fluidity, they are inferior in offset resistance, and it is necessary to further improve developability (chargeability) and durability.

In JP-A-62-226260, JP-A-63-139365, JP-A-3-50559 and JP-A-6-208244, a polypropylene modified with carboxylic acid or maleic acid is contained. Toners or resin compositions for toners have been proposed.
In these toners, there is no regulation on the relationship between the release agent and the resin composition, and it is further desired to maintain the fluidity and improve the hot offset resistance.

In order to expand the fixing area (non-offset area), it is necessary to add two or more releasing agents to the toner in JP-A-60-93457, JP-A-4-274247 and JP-A-4-27447. No. 299357, JP-A-4-33
7737, JP-A-6-208244, and JP-A-7-281478. In these toners, there is no regulation on the relationship between the release agent and the resin composition, and there is still a problem in uniformly dispersing the release agent in the toner particles.

For the purpose of improving the fluidity of the toner, it is possible to use a mixture of a silica fine powder which has been subjected to a hydrophobizing treatment and then a silicone oil treatment, and a silica fine powder having a trimethylsiloxyl group, which is used in combination. Japanese Patent Laid-Open No. 4-50861. However, the effect is insufficient in a toner system containing a wax component having an acid group for low-temperature fixability and high durability, and charging stability, toner contact member contamination, etc. must be solved. There are challenges that need to be addressed.

[0033]

As described above, the performance improvement of the toner is still insufficient and there are many points to be improved.

The object of the present invention is to solve the problems of the prior art, to realize a uniform image without fading in any environment, and to be applied to an electrophotographic process exhibiting high developability. Another object is to provide a toner for developing an electrostatic charge image that enables the above.

A further object of the present invention is to supply an electrostatic charge image developing toner exhibiting high performance in fixing property and offset resistance.

A further object of the present invention is to develop a highly durable electrostatic image which can prevent toner from sticking to or fusing to a developer contact member such as a light-sensitive material, and can prevent damage from occurring. To provide toner for use.

[0037]

The present invention provides a toner for developing an electrostatic charge image, comprising toner particles containing at least a resin composition containing a polymer component, a colorant and a wax, and an external additive. Ingredients are 1-30 mg KO
The external additive contains a wax having an acid value of H / g,
Non-silicone oil-treated hydrophobic hydrophobicity as measured by methanol aqueous solution (60:40) is 5 to 20%
A silica fine powder A and a silicone oil-treated hydrophobic silica fine powder B having a hydrophobicity of 5 to 30% , and
The content is A: B = 10: 90 to 60:40 in weight ratio.
The toner for developing an electrostatic image, characterized in that it.

[0038]

The reason why the toner according to the present invention exhibits the effects of the present invention is considered as follows.

That is, toner particles designed to have both low-temperature fixability and hot offset resistance by a wax having a certain acid value are impaired by continuing high durability in a high temperature and high humidity environment. By having the above-mentioned external additive inorganic fine powder, it becomes possible to have excellent fluidity and uniform charging property, and it becomes possible to transfer it evenly onto a transfer material such as paper, which is caused by aggregation of toner. It was possible to prevent electrostatic offset due to offset and non-uniform charging, and expand the range of fixing and offset resistance.

Further, the toner of the present invention is caused by the high durability of the toner particles designed to have both low temperature fixing property and anti-offset property by the wax having a certain acid value in a high temperature and high humidity environment. By including contamination of the photoconductor and the developer carrier as external additives, it becomes possible to obtain the charging stability enhanced by the acid-modified wax under any environment, and to aggregate the toner. It is possible to prevent adhesion, fusion, contamination, and damage to the photosensitive drum, which is the toner contact member, and the developer carrier.

This is because the external additive has a hydrophobicity measured by a specific method, so that the influence of humidity of the external environment can be reduced, and at the same time, the inorganic fine powder treated with silicone oil can be reduced. This is because the toner fluidity obtained by holding both the body and the inorganic fine powder that has not been treated with silicone oil makes it easier for the toner to obtain a uniform charge, and is also a non-silicone oil treated inorganic fine powder that does not adhere easily. By simultaneously holding the body and the silicone oil-treated inorganic fine powder capable of preventing damage to the toner contact member, it has become possible to create a toner that can be durable for a long period of time.

Each material will be described below.

The wax used in the toner for developing an electrostatic image of the present invention is characterized by having an acid value of 1 to 30 mgKOH / g. Since the wax used in the present invention has the above specific acid value, other toner components,
Particularly, good dispersibility / compatibility with the resin binder component is realized, which contributes to low temperature melting of the toner, and high offset resistance is achieved because wax can exist in the toner with a certain dispersion diameter. You can do it.

The acid value of the wax used in the present invention is 1 to
30 mgKOH / g, preferably 1-15 mgK
OH / g. If the acid value is less than 1 mg KOH / g,
The effect of acid is not fully exerted. Also, the acid value is 30 mg
When it exceeds KOH / g, it is not preferable because it is easily affected by environmental humidity and it becomes difficult to obtain stable charging performance.

As the type of wax, various wax components such as paraffin wax derivative, microcrystalline wax derivative, Fischer-Tropsch wax derivative, polyolefin wax derivative and carnauba wax derivative can be used.

The wax used in the present invention is preferably a polyolefin wax acid-modified product, particularly preferably an acid-modified polypropylene wax, from the viewpoint of compatibility / dispersibility with a resin binder.

The wax is an acid monomer selected from at least one of maleic acid, maleic acid half ester and maleic anhydride in view of the relationship with the constituent monomers that are preferably contained in the resin polymer component described later. Therefore, the modified polyolefin wax (more preferably polypropylene wax) is preferable.

Examples of the polypropylene wax include homopolymers of propylene and copolymers of propylene and other olefins (especially ethylene is preferable).
The propylene copolymer preferably has a propylene component of 60% by weight or more.

As the acid monomer used for modifying the wax, the same ones as those used for adjusting the acid value of the polymer component can be used.

In the present invention, a wax having no acid group may be used together.

As specific examples, various wax components such as polyolefin wax such as polyethylene and polypropylene, paraffin wax, microcrystalline wax, Fischer-Tropsch wax, carnauba wax can be used.

These waxes are preferably used in an amount of 0.5 parts by weight or more and 20 parts by weight or less with respect to 100 parts by weight of the binder resin.

The type of the binder resin used in the present invention is, for example, a homopolymer of styrene such as polystyrene, poly-p-chlorostyrene, polyvinyltoluene and the like or a substitution product thereof; styrene-p-chlorostyrene copolymerization. Coal, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-acrylic acid ester copolymer, styrene-methacrylic acid ester copolymer, styrene-α-chloromethyl methacrylate copolymer, styrene- Acrylonitrile copolymer, styrene-vinyl methyl ether copolymer, styrene-vinyl ethyl ether copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile- Styrene-based copolymers such as indene copolymers Combined; polyvinyl chloride, phenol resin, natural modified phenol resin, natural resin modified maleic acid resin, acrylic resin, methacrylic resin, polyvinyl acetate, silicone resin, polyester resin, polyurethane resin, polyamide resin, furan resin, epoxy resin, xylene Resin, polyvinyl butyral, terpene resin, coumarone indene resin, petroleum resin, etc. can be used. A crosslinked styrene resin is also a preferable binder resin.

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

The polymer component used in the present invention is 1 to 1
It preferably has an acid value of 00 mg KOH / g. This is because the wax having an acid value used in the present invention can be effectively dispersed.

When the acid value is less than 1 mgKOH / g, this effect becomes difficult to obtain, and when it exceeds 100 mgKOH / g,
It is not preferable because it is easily affected by environmental humidity.

The polymer component used to obtain the above acid value is most preferably a polymer containing at least one of a carboxyl group, a carboxylic acid anhydride group and a carboxylate group. For example, acrylic acid, acrylic acid such as methacrylic acid, α-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 There are maleic anhydride, etc.,
A desired polymer is obtained by copolymerizing such a monomer alone or in a mixture with another monomer.

Among these, maleic acid, maleic acid-half ester and maleic anhydride are particularly preferable monomer components. This is because the monomer has excellent compatibility with the acid-modified wax.

In the present invention, the polymer component of the toner preferably contains substantially no tetrahydrofuran (THF) insoluble component. Specifically, it is 5% by weight or less, preferably 3% by weight or less, based on the polymer component.

The THF-insoluble matter in the present invention means the weight ratio of the polymer component (substantially crosslinked polymer) which becomes insoluble in the THF solvent of the polymer component of the toner, and the resin composition containing the crosslinking component. It can be used as a parameter indicating the degree of cross-linking. The THF-insoluble matter is defined as a value measured as follows.

That is, 0.5 to 1.0 g of a toner sample is weighed (w ₁ g), and a cylindrical filter paper (for example, No.
86R), put on a Soxhlet extractor, and extracted with 100 to 200 ml of THF as a solvent for 6 hours. After evaporating the soluble component extracted by the solvent,
Vacuum-dry at 100 ° C. for several hours, and weigh the amount of the THF-soluble resin component (w ₂ g). The weight of the components other than the resin component such as the magnetic substance, pigment and wax in the toner is (w ₃ g). The THF insoluble content is calculated from the following formula.

THF insoluble matter (%) = [{w ₁ − (w ₃ + w
₂ )} / (w ₁ −w ₃ )] × 100

If the THF insoluble content exceeds 5% by weight, the low temperature fixability is deteriorated.

T of the polymer component in the toner composition of the present invention
The GPC chromatogram measured by the HF-soluble matter has a main peak in a region of at least a molecular weight of 3 × 10 ^{3 to} 3 × 10 ⁴ (more preferably 5 × 10 ³ to 2 × 10 ⁴ ), and It is preferable to have a subpeak or a shoulder in a region having a molecular weight of 1 × 10 ^{5 to} 3 × 10 ⁶ (more preferably 5 × 10 ⁵ to 1 × 10 ⁶ ).

In the GPC chromatogram, the area ratio of the polymer component having a molecular weight of 1,000,000 or more is 1 to
It is preferably 20% (more preferably 3 to 10%). The molecular weight is 1,000,000 or more and the soluble component in THF is 1
By the presence of -20%, the offset resistance can be improved without hindering the low temperature fixing, and at the same time, the storage stability of the toner when it is left at a high temperature can be improved.

In the present invention, the molecular weight distribution of the polymer component of the resin composition of the toner is measured by GPC (gel permeation chromatography) under the following conditions.

<GPC measurement conditions for resin composition and polymer> Device: GPC-150C (manufactured by Waters) Column: KF801-7 (manufactured by Showdex) 7 consecutive temperatures: 40 ° C Solvent: THF (tetrahydrofuran) Flow rate : 1.0 ml / min. Sample: 0.1 m of a sample having a concentration of 0.05 to 0.6% by weight
l injection

The polymer component used is a low molecular weight polymer component (molecular weight 5 × 10 ⁴ in GPC chromatogram).
Acid value (A _VL ) and high molecular weight polymer (GPC)
(A region with a molecular weight of 5 × 10 ⁴ or more in the chromatogram)
Acid value (A _VH ) of the wax satisfies the following condition A _VL > A _VH , and the wax has an acid value (A _VWAX ) satisfying the following condition.

A _VL > A _VWAX , A _VWAX > 0 (mgKOH / g)

As a result of intensive studies by the present inventors, in the combination of the above polymer component and wax, both have an acid value, the acid value of the polymer component is A _VL > A _VH , and the wax acid It has been found that it is preferable for the toner that the relationship between the valency and the acid value of the low molecular weight polymer also satisfies the above conditions.

By controlling the compatibility between the wax and the polymer component, especially the low molecular weight polymer, the low temperature fixing property and the offset resistance can be dramatically improved.

Since the acid value of the polymer component is A _VL > A _VH , the acid value having an acid value acts more on the low molecular weight polymer component than on the high molecular weight polymer component, and at a low temperature due to its plasticizing effect. Demonstrate fixability.

Further, in the polymer component, when the acid value (A _VWAX ) of the wax component is in the range of A _VL > A _VWAX with respect to the acid value of the low molecular weight polymer, the fluidity and charge stability of the toner are further improved. It became clear that it stabilizes for a long time.

When the acid value of the polymer component is A _VL ≦ A _VH , the toner charging stability is lowered, and even if a wax having an acid value is contained, the low temperature fixability and the offset resistance are effectively improved. Is difficult.

The acid value of the polymer component is A _VL > A _VH , and the acid value of the wax is A _VL ≤A with respect to the acid value of the low molecular weight polymer.
_In the case of _VWAX , offset resistance and toner chargeability under high humidity are deteriorated.

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

0.5 × A _VL > A _VWAX > 0.05 × A _VL

Further, according to the present invention, the acid value (A
_VWAX ) is 1 to 15 mgKOH / g, and the acid value (A _VL ) of the low molecular weight polymer component is 21 to 35 mgKOH / g.
And the acid value (A _VH ) of the high molecular weight polymer is 0.5 to
It is preferably 11 mgKOH / g.

Further, the polymer component preferably used in the present invention has a low molecular weight polymer having an acid value (A _VL ) of 21 to 35 m.
gKOH / g, the acid value (A _VH ) of the high molecular weight polymer is 0.5 to 11 mg KOH / g, and the difference is within the range of 10 ≦ (A _VL −A _VH ) ≦ 27. Is preferred.

The low temperature fixability is determined by the Tg of the low molecular weight polymer component.
And, the same Tg and the same molecular weight distribution can be obtained by including an acid component in this component and further increasing the acid value of the high molecular weight polymer component by 10 mgKOH / g or more, though it is affected by the molecular weight distribution. The viscosity can be made lower than that of the resin composition having an acid value outside the above range.

This is because by setting the acid value of the high molecular weight polymer component to be 10 mgKOH / g or more lower than the acid value of the low molecular weight polymer component (acid value 0.5 to 11 mgKOH / g), the low molecular weight polymer component To some extent to suppress the entanglement of the high molecular weight polymer component and the molecular chain of the wax, and
It is considered that the viscosity is reduced on the low temperature side, the elastic property is maintained on the high temperature side, and the wax has a certain domain diameter in the toner particles, so that a sufficient releasing effect can be obtained. As a result, low-temperature fixing in high-speed machines,
This leads to improvement in development characteristics.

On the other hand, the difference in acid value is 27 mgKOH / g
If it exceeds the range, problems occur in the mixing property of the low molecular weight polymer component and the high molecular weight polymer component and the dispersibility of the wax component in the toner, and the offset resistance and the developability tend to be deteriorated.

Further, the acid value of the low molecular weight polymer component is 21.
When it is more than mgKOH / g, the rising property of charging becomes good.

On the other hand, the acid value of the low molecular weight polymer component is 35 m.
If it exceeds gKOH / g, the developability under high humidity tends to decrease.

The acid value of the high molecular weight polymer component is 0.5 mgK
If it is less than OH / g, the low molecular weight polymer component (acid value 2
(1 to 35 mgKOH / g) and the wax are not compatible, the offset resistance is lowered, and fog is likely to occur.

In the present invention, the acid value (JIS acid value) of the low molecular weight polymer component and the high molecular weight polymer component of the toner polymer component
Is calculated by the following method.

<Preparation of each component> [Device configuration] LC-908 (Nippon Analytical Industry Co., Ltd.) JRS-86 (Company; repeat injector) JAR-2 (Company; Autosampler) FC-201 (Gilson Company; Hula cushion collector)

[Column configuration] JAIGEL-1H to 5H diameter (20 mm × 600 m)
m: Preparative column)

[Measurement conditions] Temperature: 40 ° C Solvent: THF Flow rate: 5 ml / min. Detector: RI

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

<Measurement of acid value> 1) 0.1 to 0.2 g of a ground product of a sample 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) Titrate the solution in the flask with a burette using an alcohol solution of 0.1N KOH. The amount of the KOH solution at this time is S (ml). A blank test is performed at the same time, and the amount of KOH solution at this time is set to B
(Ml).

5) The acid value is calculated by the following formula.

[0096]

[Equation 1]

The acid value of the wax in the present invention was measured by the following measuring method.

<Preparation of wax> Toner sample 0.5
~ 1.0 g is weighed, and a cylindrical filter paper (for example, Toyo Filter Paper N
O. 86R) and toluene 100 to 2 as a solvent.
Soxhlet extraction was carried out for 20 hours with 00 ml, and the soluble components extracted with the solvent were evaporated, and then 10
Vacuum dry at 0 ° C. for several hours. After adding 20 ml of chloroform to the obtained extract and allowing it to stand for 1 hour, it is filtered through a membrane filter having a pore size of 0.45 μm and dried to obtain a wax component.

<Measurement of acid value> -Equipment and instruments Direct balance balance Erlenmeyer flask (200 ml) Measuring cylinder (100 ml) Micro burette (10 ml) Electric heater / reagent Xylene dioxane N / 10 potassium hydroxide standard methanol solution 1% phenol lid Rain solution (indicator) -Measuring method 1-1.5 g of wax is precisely weighed in an Erlenmeyer flask, 20 ml of xylene is added thereto, and the mixture is heated and dissolved. After dissolution, 20 ml of dioxane was added, and while the solution did not become cloudy or haze, add 1 with N / 10 potassium hydroxide standard methanol solution.
Titrate as quickly as possible with a% phenolphthalein solution. A blank test is conducted at the same time. Calculation formula Acid value = [5.61 × (A−B) × f] / S where A: N / 10 required for the main test and the number of ml of standard methanol solution of potassium hydroxide B: N required for the blank test Number of ml of / 10 potassium hydroxide standard methanol solution f: N / 10 Factor of potassium hydroxide standard methanol solution S: Sample (g)

The electrostatic image developing toner of the present invention preferably uses an organometallic compound as a charge control agent,
Particularly, those containing an organic compound rich in vaporizability and sublimability as a ligand or a counter ion are useful. As such a metal complex, a metal complex type monoazo compound is preferably used from the viewpoint of chargeability. As the metal complex type monoazo compound, Japanese Patent Publications No. 41-20153 and No. 42-2.
No. 7596, No. 44-6397, No. 45-2.
There are metal complexes of monoazo dyes described in Japanese Patent No. 6478 and the like. Especially in terms of dispersibility and chargeability,
The metal complex type monoazo compound represented by the following general formula (I) is preferable, and among them, the metal complex type monoazo iron complex in which the central metal is iron is preferably used. More preferably, a monoazo iron complex represented by the following general formula (II) is used.

[0101]

[Chemical 2]

[0102]

[Chemical 3]

The content of the metal complex type monoazo compound is preferably 0.5 to 5 parts by weight, particularly preferably 0.2 to 3 parts by weight, based on 100 parts by weight of the toner binder resin. If the content of the metal complex type monoazo compound is too large, the fluidity of the toner is deteriorated and fogging easily occurs, 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 magnetic toner containing a magnetic material. Magnetic materials that can be used include metal oxides containing elements such as iron, cobalt, nickel, copper, magnesium, manganese, aluminum and silicon. These magnetic materials are preferably magnetic powders having a BET specific surface area by the nitrogen adsorption method of preferably 1 to 20 m ² / g, particularly 2.5 to 12 m ² / g, and a Mohs hardness of 5 to 7. The shape of the magnetic material includes octahedron, hexahedron, sphere, needle and scaly shape, but octahedron, hexahedron, sphere and the like with less anisotropy are preferable. This is because those having an isotropic shape can achieve good dispersion with respect to the binder resin and wax used in the present invention. The average particle size of the magnetic material is
The thickness 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.

The above 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.
It is particularly preferably 70 to 150 parts by weight. If the amount is less than 60 parts by weight, the toner transporting property is insufficient and the developer layer on the developer carrying member becomes uneven so that image unevenness tends to occur, and further, the image density due to the excessive increase in the charge of the developer may increase. It tended to occur. On the other hand, if the amount exceeds 200 parts by weight, the developer cannot be sufficiently charged, so that the image density tends to decrease.

The external additive used in the toner of the present invention is a non-silicone oil-treated hydrophobic inorganic fine powder A having a hydrophobicity of 5 to 40% measured with a methanol-water solution (60:40). The silicone oil-treated hydrophobic inorganic fine powder B having the same degree of hydrophobicity of 5 to 30% is also included.

Further, when the hydrophobic inorganic fine powder A and the silicone oil-treated inorganic fine powder B are mixed and used, the weight ratio is within the range of [A]: [B] = 10: 90 to 60:40. is there.

If the proportion of the fine powder A is less than 10%, it is difficult to obtain preferable toner fluidity and it is difficult to obtain stable developability for a long period of time, and if it exceeds 60%, the toner contact member is damaged or melted. Wearing is easy.

Examples of the inorganic fine powder include silica fine powder, titanium oxide fine powder, aluminum oxide fine powder, and the like, but silica fine powder is preferable for charge stability and developability.

As the silica fine powder, it is possible to use both a so-called dry method produced by vapor phase oxidation of a silicon halide or a dry silica called fumed silica, and a so-called wet silica produced from water glass or the like. But,
There are few silanol groups on the surface and inside, and Na ₂
Dry silica having less production residues such as O and SO ₃ ²⁻ is preferable. In the case of dry silica, it is also possible to obtain a composite fine powder of silica and another metal oxide by using another metal halogen compound such as aluminum chloride and titanium chloride together with a silicon halogen compound in the manufacturing process. , Including those.

Both the inorganic fine powders A and B have been hydrophobized by chemically treating them with an organic silicon compound or the like that reacts with the inorganic fine powders. A preferred method is a method of treating a dry silica fine powder produced by vapor phase oxidation of a silicon halogen compound with a silane coupling agent. Examples of the silane coupling agent used in the hydrophobic treatment include hexamethyldisilazane, trimethylsilane, trimethylchlorosilane, trimethylethoxysilane, dimethyldichlorosilane, methyltrichlorosilane, allyldimethylchlorosilane, allylphenyldichlorosilane. , Benzyldimethylchlorosilane, bromomethyldimethylchlorosilane, α-chloroethyltrichlorosilane, β-chloroethyltrichlorosilane, chloromethyldimethylchlorosilane, triorganosilylmercaptan, trimethylsilylmercaptan, triorganosilylacrylate, vinyldimethylacetoxysilane, Dimethyldiethoxysilane, dimethyldimethoxysilane, diphenyldiethoxysilane, hexamethyldisiloxane, 1,3-divinyl Rutetramethyldisiloxane, 1,3-diphenyltetramethyldisiloxane, and dimethyl having 2 to 12 siloxane units per molecule and having a hydroxyl group bonded to a silicon atom directed to each terminal unit Examples include polysiloxane and the like.

The inorganic fine powder B is treated with a silicone oil such as dimethyl silicone oil after being chemically hydrophobized with the silane coupling agent or the like as described above, or simultaneously with the silane coupling agent. .

25 is a preferable silicone oil.
Those having a viscosity at 30 ° C. of 30 to 1000 centistokes are used, and for example, dimethyl silicone oil, methylphenyl silicone oil, α-methylstyrene modified silicone oil, chromium phenyl silicone oil, fluorine modified silicone oil and the like are particularly preferable.

As the method for treating silicone oil, for example, silica fine powder treated with a silane coupling agent and silicone oil may be directly mixed by using a mixer such as a Henschel mixer, or fine powder as a base. You may use the method of spraying silicone oil on. Alternatively, a method may be used in which silicone oil is dissolved or dispersed in a suitable solvent, and then silica fine powder is added and mixed to remove the solvent.

The inorganic fine powder A is a methanol-water solution (6
0:40) has a hydrophobicity of 5 to 20%, and the inorganic fine powder B has a hydrophobicity of 5 to 30%.

When the degree of hydrophobicity is less than 5%, the inorganic fine powder is liable to aggregate and it is difficult to effectively disperse it on the toner, which is not preferable. On the other hand, if the degree of hydrophobicity exceeds this range, it will be unduly affected by environmental humidity, making it difficult to obtain stable charging.

The degree of hydrophobicity of the inorganic fine powder used in the present invention is as follows: methanol-water solution (60: 4)
The degree of hydrophobicity measured by 0) is used.

<Hydrophobicity measurement method> 1) Take 1.0 g of a sample in a 200 ml separating funnel,
100 ml of methanol-water solution (60:40) is added.

2) A separatory funnel is set in a Turbula shaker mixer type T2C (manufactured by Shinmaru Enterprises Co., Ltd.).

3) 90r. p. dispersion for 10 minutes.

4) The separating funnel is taken out from the Turbula shaker mixer type T2C and allowed to stand for 10 minutes.

5) After leaving still for 10 minutes, 20 to 30 ml is extracted, and then it is collected in a 10 mm cell.

6) Using a methanol-water solution (60:40) as a blank, the turbidity is measured (wavelength 500 nm) with a colorimeter (digital double beam spectrophotometer UV-210 type (manufactured by Shimadzu Corporation). The value (transmittance) is taken as the hydrophobicity.

If necessary, an external additive other than silica fine powder or titanium oxide fine powder may be added to the toner for developing an electrostatic image of the present invention. For example, resin fine particles or inorganic fine particles that act as a charging aid, a conductivity-imparting agent, a fluidity-imparting agent, an anti-caking agent, a release agent at the time of heat roll fixing, a lubricant, an abrasive, etc. For example, lubricants such as Teflon, zinc stearate, polyvinylidene fluoride, and polyvinylidene fluoride are preferable. Alternatively, abrasives such as cerium oxide, silicon carbide, and strontium titanate are preferable, and strontium titanate is particularly preferable. Alternatively, for example, a fluidity-imparting agent such as titanium oxide or aluminum oxide, among which a hydrophobic agent is particularly preferable. A small amount of anti-caking agent or conductivity-imparting agent such as carbon black, zinc oxide, antimony oxide, tin oxide, etc., and white particles and black particles of opposite polarity can be used as a developing property improver. The resin fine particles, inorganic fine powder, hydrophobic inorganic fine powder, or the like mixed with the toner is 0.1 to 5 parts by weight (preferably 0.1 to 3 parts by weight) with respect to 100 parts by weight of the magnetic toner.
(Parts by weight) should be used.

The toner for developing an electrostatic image of the present invention is prepared by thoroughly mixing the toner constituent materials with a mixer such as a ball mill, and then melting, kneading and kneading with a heat kneader such as a heating roll, a kneader or an extruder. It can be produced by slaughtering, cooling and solidifying, crushing and strict classification.

[0126]

EXAMPLES The present invention will be described below with reference to specific examples, but the present invention is not limited thereto.
"Parts" means "parts by weight".

Example 1 As a low molecular weight polymer, a styrene-butyl acrylate-monobutyl maleate copolymer (peak molecular weight 10500, acid value 27 mgKOH /
g) 70 parts, and 30 parts of a styrene-butyl acrylate-monobutyl maleate copolymer (peak molecular weight 980,000, acid value 5 mgKOH / g) as a high molecular weight polymer,
After dissolving in 100 parts of reflux xylene, the organic solvent was distilled off, the obtained resin was cooled and solidified, and then pulverized to obtain a resin composition (I) for toner.

100 parts of the above-mentioned toner resin composition (I)
Parts, 100 parts of spherical magnetic iron oxide, 2 parts of a metal complex type monoazo compound represented by the following formula (III), and a maleic anhydride-modified propylene-ethylene copolymer (acid value 3.5 mg
6 parts of KOH / g and a weight average molecular weight of 9500) were uniformly mixed in advance, and this was melt-kneaded with a twin-screw extruder heated to 130 ° C. The kneaded product was cooled, coarsely pulverized with a hammer mill, and further finely pulverized with a jet mill. The obtained pulverized product was classified by wind to obtain classified powder having a weight average diameter D ₄ of 6.8 μm.

[0129]

[Chemical 4]

The following external additives were added to 100 parts of these classified powders.

As the non-silicone oil-treated hydrophobic inorganic fine powder A, silica fine powder hydrophobized with hexamethyldisilazane (HMDS) (BET specific surface area 130 m ² /
g, hydrophobicity measured by methanol-water solution (60:40) 15%) 0.6 part; as a silicone oil-treated hydrophobic inorganic fine powder B, after hydrophobizing with HMDS, 150 mm ² / s Dimethyl silicone oil 10
Silica fine powder (BET
Specific surface area 110 m ² / g, methanol-water solution (60:
A hydrophobicity of 20% measured according to 40) was used together with 0.6 parts as an external additive.

Toner (T1) was obtained by dry-mixing these external additives with the classified powder.

Example 2 A low molecular weight polymer was added to styrene-
A toner resin composition (II) was obtained in the same manner as the resin composition (I) except that the butyl acrylate-monobutyl maleate copolymer (peak molecular weight 10900, acid value 33 mgKOH / g) was used.

100 parts of the above-mentioned toner resin composition (II)
Parts, 100 parts of spherical magnetic iron oxide, 2 parts of the metal complex type monoazo compound represented by the above formula (III), maleic anhydride-modified propylene-ethylene copolymer (acid value 3.5 mg KO
H / g, 3 parts by weight average molecular weight 9500) and 3 parts by weight of linear polypropylene (weight average molecular weight 9000) were uniformly mixed in advance, and the toner (T1) was prepared in the same manner as the toner (T1).
2) was obtained.

<Example 3> In Example 1, the wax component was changed to maleic anhydride-modified polypropylene (acid value: 12 mg KO).
Toner (T3) was obtained in the same manner except that H / g and weight average molecular weight of 10,000 were 5 parts.

Example 4 In Example 1, the wax component was changed to methacrylic acid-modified polypropylene (acid value 5 mgKOH /
g, weight average molecular weight 9,000) Toner (T4) was obtained in the same manner except that 3 parts were used.

Example 5 In Example 1, the wax component was changed to acrylic acid-modified polyethylene (acid value 21 mgKOH /
g, weight average molecular weight 8000) 4 parts were obtained in the same manner as Toner (T5).

Example 6 A low molecular weight polymer was added to styrene-
A resin composition (III) for toner was obtained in the same manner as the resin composition (I) except that the butyl acrylate-monobutyl maleate copolymer (peak molecular weight 12000, acid value 0.8 mgKOH / g) was used. .

A toner (T6) was obtained in the same manner as in Example 1, except that the resin composition for toner (III) was used as the resin composition.

Example 7 A low molecular weight polymer was added to styrene-
Butyl acrylate copolymer (peak molecular weight 9800, acid value 0 mgKOH / g), high molecular weight polymer styrene-butyl acrylate copolymer (peak molecular weight 600,000, acid value 0
A resin composition for toner (IV) was obtained in the same manner as the resin composition (I) except that the composition (mgKOH / g) was used.

A toner (T) was obtained in the same manner as in Example 1 except that the resin composition (IV) for toner was used as the resin composition.
7) was obtained.

Reference Example 1 In Example 1, as the external additive, hexamethyldisilazane (H) was used as the non-silicone oil-treated hydrophobic inorganic fine powder A.
Silica fine powder hydrophobized with MDS (BET specific surface area 130 m ² / g, methanol-water solution (60:40)
Hydrophobicity measured by 15%) is 0.9 part; Silicone oil-treated hydrophobic inorganic fine powder B is hydrophobized with HMDS, and then treated with 10 parts of dimethyl silicone oil of 150 mm ² / s. Obtained silica fine powder (BET specific surface area 110 m ² / g, methanol-
Hydrophobicity of 20 as measured by aqueous solution (60:40)
%) Is the same as the toner (T
8) was obtained.

Reference Example 2 In Example 1, as an external additive, a non-silicone oil-treated hydrophobic inorganic fine powder A was used, and hexamethyldisilazane (H
Silica fine powder hydrophobized with MDS (BET specific surface area 122 m ² / g, methanol-water solution (60:40)
Hydrophobicity 35%) measured by means of 0.9 parts; Silicone oil-treated hydrophobic inorganic fine powder B is hydrophobized with HMDS, and then treated with 5 parts of 100 mm ² / s dimethyl silicone oil. Fine silica powder obtained (BET specific surface area 113 m ² / g, hydrophobicity 22% measured by methanol-water solution (60:40))
Toner (T9) was obtained in the same manner except that the amount was 0.3 part.

Reference Example 3 In Example 1, as the external additive, hexamethyldisilazane (H) was used as the non-silicone oil-treated hydrophobic inorganic fine powder A.
Titanium oxide fine powder hydrophobized with MDS (BET specific surface area 130 m ² / g, methanol-water solution (60: 4)
Hydrophobicity 18%) measured by 0) is 0.9 part; as a silicone oil-treated hydrophobic inorganic fine powder B, HMD
A silica fine powder (BET specific surface area of 110 m ² / g, measured with a methanol-water solution (60:40) was obtained by treating with 10 parts of 150 mm ² / s of dimethyl silicone oil after hydrophobic treatment with S. Hydrophobicity 2
The toner (T
10) was obtained.

<Comparative Example 1> A low molecular weight polymer was used as styrene-
Butyl acrylate copolymer (peak molecular weight 10,000,
Acid value 0 mgKOH / g) and the high molecular weight polymer except that it was a styrene-acrylic acid-monobutyl maleate copolymer (peak molecular weight 720,000, acid value 3.5 mgKOH / g), and the resin composition (I). Similarly, a resin composition for toner (III) was obtained.

In Example 1, the wax component was 3 parts by weight of linear polypropylene (weight average molecular weight 9000), and the external additive was a dry silica fine powder (BET) which had not been subjected to hydrophobic treatment.
Specific surface area 180 m ² / g, methanol-water solution (60:
Toner (T11) was obtained in the same manner except that the hydrophobicity measured by 40) was 90%).

<Comparative Example 2> In Comparative Example 1, the titanium oxide fine powder (BET specific surface area 200 m ² / g, methanol-aqueous solution (60:40), which was not subjected to the hydrophobic treatment of the external additive, was used. A toner (T12) was obtained in the same manner except that the amount of conversion (95%) was only 1.2 parts.

Table 1 shows the physical properties of the raw materials used for the toners T1 to T12, and Table 2 shows the results of the molecular weight distribution of the THF-soluble components of the toners T1 to T12 measured by GPC.

[0149]

[Table 1]

[0150]

[Table 2]

[Evaluation] The toner thus obtained was evaluated. The printout test, fixability and offset resistance test were conducted as follows.

<Printout Test> High temperature and high humidity (32.
5 ° C / 80% RH), low temperature and low humidity (10 ° C / 15% RH)
Laser beam printer L on the market under each environment
BP-830 (manufactured by Canon Inc.) was modified into the following constitution, and a printout test was conducted under the following conditions. When the toner ran out, the printout test was continued by making a notch in the toner container portion above the cartridge and replenishing the toner from there. An electrostatic latent image is formed by setting the primary charge to -690 V, a gap (290 μm) is set in a non-contact manner between the photosensitive drum and the developer layer on the developer carrying member (including magnet), and an AC bias (f = 2000 Hz; Vpp). = 160
0 V) and DC bias (Vdc = -500V) were applied to the developing drum. Printout speed is 32
It was remodeled to be one sheet (A4 horizontal) / 1 minute. The obtained image was evaluated for the following items.

Image Density The image density was evaluated by maintaining the image density at the end of printing out 20,000 sheets on ordinary plain paper for copiers (75 g / m ² ).
The image density was measured by using a "Macbeth reflection densitometer" (manufactured by Macbeth Co., Ltd.) to measure the relative density 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)
The fog was calculated by comparing the solid white after printing 5000 durable images under the environment with the whiteness of the transfer paper after printing.

Fixability The fixability was evaluated by rubbing the fixed image with a soft thin paper under a load of 50 g / cm ² , and the reduction rate (%) of the image density before and after the rubbing. As a test paper, plain paper (90 g / m ² ) for a copying machine, in which the toner was fixed, was used. ◎ (excellent): less than 5% ○ (good): 5% to 10% △ (possible): 10% to 20% × (unacceptable): 20% or more

Offset resistance The offset resistance was evaluated by printing out a sample image having an image area ratio of about 5% and measuring the degree of stain on the image. Plain paper for copiers (64 g / m ² ) was used as the test paper. ◎: Very good (no occurrence) ○: Good (almost no occurrence) △: Practical x: Not practical

Degree of fusion of toner to developer carrier 200 under high temperature and high humidity (32.5 ° C./80% RH) environment
After printing 00 sheets, the developer carrying member was visually observed and evaluated by the degree of toner fusion to the developer carrying member. ◎: Very good (not generated) ○: Good (almost no generation) △: Practical (toner fusion only on the edges) ×: Practical (toner adhered to the entire surface)

Degree of Toner Fusing to Photosensitive Drum 200 in an environment of high temperature and high humidity (32.5 ° C./80% RH)
The degree of drum fusing was evaluated by observing the solid black image after printing 00 sheets and counting the number of white spots associated with the drum fusing. ◎: Very good (not generated) ○: Good (less than 10 points) △: Practical (10 points or more and less than 50 points) ×: Practical (50 points or more, generated on the entire surface)

According to the above evaluation method, see Examples 1 to 7.
The toners of Consideration Examples 1 to 3 and Comparative Examples 1 and 2 were evaluated. The results are summarized in Table 3.

[0160]

[Table 3]

[0161]

As described above, the toner of the present invention realizes a uniform image without fading in any environment, exhibits high developability, and has high fixability and offset resistance. In addition to high performance, it can prevent toner from sticking and fusing to the developer contact member such as developer carrier / photosensitive material, and can prevent damage from occurring. Highly durable. It is a toner that is highly applicable to electrophotographic processes.

Continuation of front page (56) Reference JP 62-227159 (JP, A) JP 62-196672 (JP, A) JP 61-249059 (JP, A) JP 61-138259 (JP , A) JP 9-166884 (JP, A) JP 8-234487 (JP, A) JP 8-227171 (JP, A) JP 8-152738 (JP, A) JP 8-95298 (JP, A) JP-A-7-281478 (JP, A) JP-A-7-160039 (JP, A) JP-A-6-208244 (JP, A) JP-A-5-66601 (JP, A) A) JP 4-50861 (JP, A) JP 3-50561 (JP, A) JP 3-50559 (JP, A) JP 3-43746 (JP, A) JP 2 −287364 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) G03G 9/08

Claims (5)

(57) [Claims] 1. A toner for developing an electrostatic image, comprising toner particles containing at least a resin composition containing a polymer component, a colorant and wax, and an external additive, wherein the wax component is 1 to 30 mgKOH / g. A non-silicone oil-treated hydrophobic silica fine powder A having a hydrophobicity of 5 to 20 % as measured by an aqueous methanol solution (60:40). Hydrophobicity is 5-30
% Of the silicone oil-treated hydrophobic silica fine powder B , and the content thereof is A: B = 10: 90 by weight.
A toner for developing an electrostatic charge image, wherein the toner is about 60:40 . 2. The resin composition comprises 1 to 100 mg KOH.
The toner for developing an electrostatic charge image according to claim 1, having an acid value of / g. 3. A toner according to claim 1 or 2 is an acid-modified polyolefin wax the wax has an acid number of 1~15mgKOH / g. 4. The wax is at least one of maleic acid, maleic acid half ester or maleic anhydride.
The toner for developing an electrostatic charge image according to claim 3 , which is a polyolefin wax modified with an acid monomer selected from one or more kinds. 5. The toner for developing an electrostatic charge image according to claim 4 , wherein the polyolefin wax is a polypropylene wax.