JP3086994B2 - 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 a toner for developing an electrostatic image for visualizing an electrostatic latent image in an image forming method such as electrophotography and electrostatic recording.

[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.
Various methods are described in Japanese Patent Publication No. JP-B-43-24748 and Japanese Patent Publication No. 43-24748.

The developing methods applied to the electrophotographic method and the like are roughly classified into a dry developing method and a wet developing method. The former is further classified into a method using a two-component developer and a method using a one-component developer.

[0004] As a toner applied to these dry development methods, fine powders in which dyes and pigments are dispersed in a natural or synthetic resin are conventionally used. For example, a colorant dispersed in a binder resin such as polystyrene is 1 to 30 μm.
Particles pulverized to about m are used as toner. As the magnetic toner, a toner containing magnetic particles such as magnetite is used. In the case of using a two-component developer, the toner is usually used by being mixed with carrier particles such as glass beads and iron powder.

[0005] Any toner must have a positive or negative charge depending on the polarity of the electrostatic latent image to be developed.

In order to cause the toner to retain electric charge, it is possible to use the frictional charging property of a resin which is a component of the toner. However, in this method, since the charging property of the toner is small, an image obtained by development is easily fogged. , Will be blurred. Accordingly, in order to impart a desired triboelectric charging property to the toner, a dye, a pigment for imparting the charging property, and a charge controlling agent have been added. Today, as charge control agents known in the art, nigrosine dyes, azine dyes, triphenylmethane dyes and pigments, quaternary ammonium salts or quaternary ammonium salts are added to the side chain as positive triboelectric charging properties. Polymers having the same are known.

[0007] Each of these charge control agents requires a certain period of time before they have an appropriate charge amount. For this reason, when copying immediately after installing a copying machine,
In the case where copying is performed after being stopped for a long period of time, or when copying is performed after being left in a high humidity environment, the charge amount tends to be insufficient. As a result, fogging occurs, or several to several tens of copies are required to obtain an appropriate image density.

Further, when these charge control agents are applied to one-component developers (magnetic and non-magnetic), such a delay in the rise of the charge causes a ghost (the history of the previous image remains on the developing sleeve or the like). This is considered to be the cause of the phenomenon that the same shade as the previous image appears (positive ghost) or the inverted shade appears (negative ghost) in the cycle of the phenomenon / sleeve.

[0009] Each of the above charge control agents has a specific disadvantage. Nigrosine dyes are colored and cannot be applied to color toners, and the charge amount tends to decrease as the number of copies increases. The quaternary ammonium salt has a low charge amount when applied to a magnetic toner, and a sufficient image density cannot be obtained particularly in a high humidity environment. In addition, the charge control agent causes a problem in dispersibility in a resin and a problem in storage stability. At present, there is a strong demand for the development of charge control agents that satisfy all of these.

[0010]

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

That is, an object of the present invention is to provide a toner for developing an electrostatic image capable of obtaining an image having a high image density, no fog, and no ghost.

It is another object of the present invention to provide a toner for developing an electrostatic image, which has a proper charge amount very quickly.

Another object of the present invention is to provide a toner for developing an electrostatic charge image which can provide a high image density from the beginning, does not gradually increase the image density, and does not cause a decrease in density for long-term durability. It is in.

Another object of the present invention is to provide a toner for developing an electrostatic charge image which can stably obtain a high image density even under high temperature and high humidity and does not damage a copying machine main body.

Another object of the present invention is to provide a toner for developing an electrostatic charge image which has good environmental dependency and can obtain a good image without change from low temperature and low humidity to high temperature and high humidity.

Means and Action for Solving the Problems The above object is achieved by the following constitutions. That is, a first aspect of the present invention is a toner for developing an electrostatic charge image, characterized in that a compound in which at least two or more imidazole derivatives are linked by a linking group having a conjugate system is contained in a binder resin. A second aspect of the present invention includes an imidazole derivative having a water content of 500 to 3000 PPM at normal temperature and normal humidity and a change rate of water content between normal temperature and normal humidity conditions and high temperature and high humidity conditions of 250% or less. A third aspect of the present invention is a toner for developing an electrostatic image, comprising: a compound represented by the following general formula (II):

[0017]

Embedded image

[Wherein R ₁ , R ₂ , R ₃ and R ₄ represent a hydrogen atom, an alkyl group, an aralkyl group or an aryl group, which may be the same or different,
Each may have a substituent. X represents a saturated linking group having 2 or more carbon atoms. The fourth aspect of the present invention is a compound represented by the following general formula (III):

[0019]

Embedded image

[Wherein R ₁ , R ₂ , R ₃ and R ₄ represent a hydrogen atom, an alkyl group, an aralkyl group or an aryl group, which may be the same or different,
Each may have a substituent. ] And a magnetic fine powder, wherein the variation coefficient of the particle size of the magnetic fine powder is 30% or less.

The use of an imidazole derivative as a charge control agent in an electrophotographic developer is disclosed in JP-A-62-287262, JP-A-61-217055, and JP-A-62-17055.
It is known in, for example, JP-A-9-187350. However, some imidazole derivatives have an insufficient charge amount, and many of them do not show a sufficient charge amount even in a high-temperature and high-humidity environment.

Further, in addition to the above, Japanese Patent Application Laid-Open No. 1-262555
JP, JP-A-2-18570, JP-A-2-87
The compounds of the imidazole derivatives disclosed in JP-A-164, JP-A-2-176762 and JP-A-3-71150 are preferable because the charge rises quickly and is preferred. When a large amount of wax or the like is contained, a sufficient charge amount may not be obtained. Especially in high humidity environments
This causes a reduction in image density. Furthermore, when the number of copies advances in a high-temperature, high-humidity environment, the image density gradually decreases. In severe cases, film-like deposits are formed on the photosensitive drum, and the amount of offset toner to the fixing roller increases. There is also a phenomenon that the web becomes dirty.

The compound of the imidazole derivative according to the first aspect of the present invention is novel and different from the above-mentioned compounds. Specifically, the above-mentioned compound is obtained by dimerizing an imidazole derivative using a methine group as a linking group, and the compound according to the present invention in which two or more imidazole derivatives are linked by a linking group having a conjugated system has a structure Are different.
Further, the present inventors have examined these known imidazole derivatives, and have confirmed that toners using these imidazole derivatives as charge control agents have indeed good developability. However, although an extremely good image can be obtained in an ideal environment, as described above, for example, when the copy environment becomes poor such as high humidity or an increase in the number of times of copying, the image quality such as a decrease in image density is deteriorated. Some degradation occurs. The present inventors further examined this toner, and found that the triboelectric charge amount was almost at the lower limit, and that there was no room to absorb the change in the developing property due to such deterioration of the copying environment. Based on these findings, when imidazole derivatives are linked by conjugated groups instead of methine groups, the imidazole derivatives have excellent properties such as dispersibility, thermal stability, and triboelectric charging speed with respect to the inherent resin. Was found that the amount of positive triboelectric charge was increased without deteriorating the first aspect of the present invention.

The performance of the first imidazole derivative multimerized product of the present invention is particularly preferably linked with phenylene or propenylene.

Hereinafter, specific examples of the above-mentioned charge control agents according to the first aspect of the present invention will be shown, but these are also taken into consideration in terms of ease of synthesis and the like, and do not limit the first aspect of the present invention at all.

[0026]

Embedded image

[0027]

Embedded image

Further, the present inventors have found that by controlling the water content of the imidazole compound, a sufficient charge amount can be obtained and that it can be maintained even in a high-temperature and high-humidity environment. It was done. Methods for controlling the water content include, but are not limited to, a sufficient heat treatment, washing with a solvent, recrystallization, improvement of raw material purity, and the like. In the case of an imidazole compound, by lowering the water content under normal temperature and normal humidity conditions to 3000 PPM or less, image density is reduced in long-term durability, film-like deposits on the photosensitive drum (filming), and offset are increased. Can be prevented. More preferably 2000P
It is preferably at most PM, more preferably at most 1500 PPM. All of the above-mentioned obstacles are phenomena as if a viscous substance is mixed in the toner, and an imidazole compound having a high water content seems to behave in a high temperature and high humidity environment.

On the other hand, the water content under the condition of normal temperature and normal humidity is 500 P
When the particle diameter is lower than PM, blotching (a phenomenon in which extremely highly charged fine particles adhere to the surface of the developer carrying sleeve and hinder the charging of other toners, and as a result, the carrying state of the developer is disturbed) is likely to occur.

In addition to controlling the water content under normal temperature and normal humidity conditions, the above function is enhanced and effective by suppressing the change rate of the water content between normal temperature and normal humidity conditions and high temperature and high humidity conditions. In addition, the environmental dependency of the charge amount is improved. In the second aspect of the present invention, the rate of change of the water content between the normal temperature and normal humidity condition and the high temperature and high humidity condition is set to 250% or less. More preferably 200%
The following is good.

In the second aspect of the present invention, the composition preferably contains a compound represented by the following general formula (I).

[0032]

Embedded image

[Wherein R ₁ , R ₂ , R ₃ and R ₄ represent a hydrogen atom, an alkyl group, an aralkyl group or an aryl group, which may be the same or different,
Each may have a substituent. X represents a linking group. By containing the compound represented by the general formula (I), an appropriate charge amount can be obtained very quickly. As a result, a high image density can be obtained from the beginning even when copying is performed immediately after the toner is put into the developing device. Further, even when the toner is left under high temperature and high humidity, although the charge amount temporarily decreases, the charge amount returns to an appropriate amount quickly, so that a high image density can be obtained substantially immediately after the resumption.

Although the detailed mechanism is unknown, it is considered that the good level of the ghost phenomenon is related to the quick charging. That is, in the second aspect of the present invention, the charge is quickly charged, so that the charge amount distribution becomes sharp. For this reason, since the toner on the sleeve, which is the toner carrier, is occupied by the toner having an appropriate charge, the amount of the toner remaining on the sleeve without being developed is reduced, and ghost is considered to be reduced. In addition, it is considered that the generation of toner that strongly adheres to the surface of the sleeve due to a reflection force or the like is one cause of the ghost. In other words, the second toner of the present invention is charged quickly, which means that saturation is reached quickly, and it is considered that the saturation value of the charge amount is not too large. In other words, by fully utilizing the potential of charging,
Toner with an excessively high charge amount is not generated, and toner that strongly adheres to the sleeve is hardly generated. This is also considered as a ghost reduction mechanism.

However, the compound represented by the above general formula (I) is liable to be damaged by the influence of the water content. The feature of fast charging reaching saturation appears to be related to the tendency to contaminate the material carrying the developer. In addition, it was difficult to produce the above compounds at a constant moisture content at normal temperature and normal humidity. Therefore, the second effect of the present invention is particularly remarkable in the case of the above compound.

Hereinafter, specific examples of the imidazole derivative according to the second aspect of the present invention will be shown, but these examples are given in consideration of easiness of synthesis and the like, and do not limit the second aspect of the present invention at all.

[0037]

Embedded image

[0038]

Embedded image

The present inventors also have the above formula (II)
It has been found that the imidazole compound represented by the formula (1) has a higher charge amount than the conventionally known imidazole compounds and has a wider selection range of materials such as magnetic fine powder, binder resin, and wax. It was done.

The third toner of the present invention, similarly to the above-described second toner of the present invention, can obtain an appropriate charge amount very quickly, and can be copied immediately after the toner is put into the developing device.
A high image density is obtained from the beginning. Even when the toner is left in a high-temperature and high-humidity state, the charge amount temporarily decreases, but quickly returns to an appropriate charge amount, so that a high image density can be obtained substantially immediately after the restart.

Hereinafter, the above-mentioned general formula (I) according to the third aspect of the present invention will be described.
Specific examples of the charge control agent of I) are shown below, taking into consideration the ease of synthesis and the like, and do not limit the third aspect of the present invention.

[0042]

Embedded image

Further, the above-mentioned general formula (II)
When the imidazole compound represented by I) contains a substance having an effect of lowering the charge amount such as magnetic fine powder or wax, a sufficient charge amount may not be obtained. Or
In order to obtain a sufficient charge amount, the compound must be contained in a large amount. The present inventors have found that by using a magnetic fine powder having a variation coefficient of particle size of 30% or less, a sufficient charge amount can be obtained even when the compound represented by the general formula (III) is used as a charge control agent. As a result, the present invention was completed. In the fourth invention, the coefficient of variation is more preferably 25% or less.

Although the mechanism is not clear, it is considered as follows. When the particle size distribution is broad, a magnetic fine powder having a large particle size is exposed on the toner surface, and the ratio of the charge control agent to the surface area is reduced. As a result, it is considered that the charge control agent cannot come into contact with the charging member such as a metal, and the charge amount does not increase. On the other hand, a magnetic fine powder having a too small particle diameter has a strong cohesive property, and therefore may have the same effect as one lump. On the other hand, by using a magnetic fine powder having a sharp particle size distribution with a coefficient of variation of 30% or less, the exposed state of the magnetic fine powder on the toner surface becomes uniform, and even if the magnetic fine powder is sufficiently contained, the charging is prevented. Hard to inhibit.

Further, since the particle size distribution is sharp, a large amount of fine magnetic powder can be contained so that the cohesiveness is not too strong. Since such a magnetic fine powder is fine and well-dispersed, the surface area of the magnetic substance becomes large inside the toner particles. Since the magnetic material has a difference in dielectric constant with resin,
In the vicinity of the surface of the magnetic material (from the viewpoint of a capacitor), there is a possibility that the magnetic material becomes a site for charging, and a large number of such sites are present. Such a mechanism is considered that the charge amount is increased by the magnetic fine powder according to the fourth aspect of the present invention. Further, in the case of the compound represented by the general formula (III), the effect of increasing the charge amount is particularly large. this is,
The concept that the compound has a large dependence on the dielectric constant is effective, and the concept that the compound has an influence on the dispersion state can be considered.

Hereinafter, the compound represented by the above general formula (II) according to the fourth aspect of the present invention will be described.
Specific examples of the charge control agent of I) are shown below, taking into consideration the ease of synthesis and the like, and do not limit the fourth aspect of the present invention at all.

[0047]

Embedded image

As a method for incorporating the above-mentioned charge control agent according to the present invention into the toner, there are a method of adding the charge control agent inside the toner and a method of externally adding the same. The amount of these compounds used is determined by the type and presence or absence of wax, the type of binder resin, the presence or absence of additives used as necessary, the toner production method including the dispersion method, and the like. It is not limited, but is preferably used in an amount of 0.1 to 10 parts by weight, more preferably 0.1 to 5 parts by weight, based on 100 parts by weight of the binder resin. When adding externally, use resin 1
The amount is preferably 0.01 to 10 parts by weight with respect to 00 parts by weight, and particularly preferably it is mechanochemically fixed to the surface of the toner particles.

The imidazole compound used in the present invention can be used in combination with a conventionally known charge control agent.

When the toner of the present invention is used as a magnetic toner, the average particle size of the magnetic fine powder contained in the toner is preferably 0.05 to 1.0 μm, more preferably 0.1 to 0.5 μm. good. The amount contained in the magnetic toner is preferably 40 to 150 parts by weight, more preferably 60 to 100 parts by weight, per 100 parts by weight of the resin component.
１２０120 parts by weight.

Examples of the magnetic material used in the present invention include iron oxides such as magnetite, γ-iron oxide, ferrite, and iron-rich ferrite; metals such as iron, cobalt, and nickel; or metals such as aluminum, cobalt, and the like.
Examples include alloys with metals such as copper, lead, magnesium, tin, zinc, antimony, beryllium, bismuth, cadmium, calcium, manganese, selenium, titanium, tungsten, and vanadium, and mixtures thereof.

The wax used as the release agent in the present invention includes, for example, an alkylene polymer obtained by radical polymerization of alkylene under high pressure, an alkylene polymer polymerized by Ziegler catalyst under low pressure, and a high molecular weight alkylene polymer obtained by thermal decomposition. Synthetic hydrocarbons obtained by hydrogenating the distillation residue of hydrocarbons obtained by the Age method from the obtained alkylene polymer, carbon monoxide, and hydrogen-containing synthesis gas can be used. Among these hydrocarbon waxes, hydrocarbon waxes obtained by extracting and fractionating specific components are particularly suitable. Preferred are those obtained by removing the low molecular weight, extraction of the low molecular weight component, and further removing the low molecular weight component therefrom by a method such as a press sweating method, a solvent method, or a fractional crystallization method utilizing vacuum distillation.

In addition, microcrystalline wax,
Carnauba wax, sasol wax, paraffin wax and the like can also be used.

The preferred range of the molecular weight of these waxes is such that the number average molecular weight (Mn) is 500 to 1200.
And a weight average molecular weight (Mw) of 800 to 8000,
Those having w / Mn of 10 or less are preferred. When the molecular weight is smaller than the above range, blocking resistance and developability will be poor, and when the molecular weight is larger than the above range, it will be difficult to obtain good fixing properties and offset resistance.

The content of these waxes depends on the binder resin 10
It is effective to use 0.5 to 10 parts by weight with respect to 0 parts by weight.

When the above-mentioned wax is contained,
In particular, the compound represented by the general formula (III) may not be able to obtain a sufficient charge amount. For this reason, in the present invention, in the DSC curve of the toner, regarding the (1) endothermic peak at the time of temperature rise, the onset temperature at the endothermic peak is 120 ° C. or less and the endothermic peak temperature is 100 to 13 ° C.
(2) Exothermic peak at the time of temperature decrease
It is preferable that the wax is contained so that the exothermic peak temperature is in the range of 62 to 80 ° C.

By analyzing the toner data measured by the differential scanning calorimeter, the relationship between heat and toner can be known. For example, it is possible to know how much heat can be used to fix the toner, and whether the toner is strong against blocking.

In the DSC curve at the time of temperature rise, an endothermic peak accompanying the transition, melting, and dissolution of the wax component is observed. When the rise of the endothermic peak is 70 ° C. or higher, the blocking resistance is excellent, which is preferable. When the temperature is lower than 70 ° C., the storage stability is poor, and the developing property is liable to be deteriorated due to the temperature rise in the machine. Further, when the onset temperature of the endothermic peak is 120 ° C. or lower, the low-temperature fixability is excellent. When the temperature exceeds 120 ° C., the low-temperature offset resistance and the fixability become poor.

Further, the endothermic peak temperature is 100 to 130 ° C.
Within this range, good fixing properties and high-temperature offset resistance can be obtained. If the temperature is lower than 100 ° C., the wax component is dissolved in the binder resin before the temperature becomes high,
It becomes difficult to obtain sufficient offset resistance at high temperatures. On the other hand, when the temperature exceeds 130 ° C., it is difficult to obtain a sufficient fixing property.

In the DSC curve at the time of temperature decrease, an exothermic peak accompanying the transition, coagulation and crystallization of the wax component is observed. When the exothermic peak temperature is in the range of 62 to 80 ° C., good fixing properties and blocking resistance are exhibited. If the temperature is higher than 80 ° C., the temperature range in which the wax is in a molten state is narrowed, and the fixability is poor. When the temperature is lower than 62 ° C., blocking and fusing are apt to occur, and the plasticizing effect on the binder resin is maintained until a low temperature, and a nail mark may be formed on the image at the paper discharge portion. Further, when the peak intensity ratio is 10 × 1
0 is preferably at ^-3. As a result, the crystallinity of the wax component increases, the hardness at room temperature increases, and blocking hardly occurs. If less than 10 × 10 ^-3 ,
Not only does blocking resistance deteriorate, but also fusing to the photoreceptor tends to occur.

The wax component, when present on the toner surface, reduces the ratio of the charge control agent to the surface area, as in the case of the magnetic fine powder, and thus has the function of suppressing charging. Therefore, in order to obtain a sufficient charge amount even when using the compound represented by the general formula (III), it is desired to reduce the content of the wax as much as possible. In the present invention, by setting the DSC curve of the toner as described above, the wax content can be suppressed without lowering the effect of the wax, and as a result, the charge amount can be maintained at a high level.

As described above, the action of the wax occurs only when the temperature passes the fixing roller. At normal temperature, the wax is harder than the conventional wax, so that the developability is improved.

Further, in order to make the DSC curve of the toner sharp as described above, a wax component having sharp characteristics is used. Thus, the wax is easily dispersed and hardly aggregated during kneading in the toner production process. When the wax is well dispersed, the proportion of the wax in the toner surface area does not increase, which is preferable for charging the toner.

Examples of the type of the binder resin used in the present invention include a homopolymer of styrene such as polystyrene, poly-p-chlorostyrene and polyvinyltoluene and a substituted product thereof; styrene-p-chlorostyrene copolymer. 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-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile- Styrene copolymers such as indene copolymers Coalescence; polyvinyl chloride, phenolic resin, natural modified phenolic resin, natural resin modified maleic acid resin, acrylic resin, methacrylic resin, polyvinyl acetate, silicone resin, polyester resin, polyurethane, polyamide resin, furan resin, epoxy resin, xylene resin , Polyvinyl butyral, terpene resin, cumarone indene resin, petroleum resin and the like can be used.

A crosslinked styrene copolymer is also a preferred binder resin.

Examples of comonomers for the styrene monomer of the styrene copolymer include acrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate, and the like.
Such as dodecyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, phenyl acrylate, methacrylic acid, methyl methacrylate, ethyl methacrylate, butyl methacrylate, octyl methacrylate, acrylonitrile, methacrylonitrile, acrylamide, etc. A monocarboxylic acid having a heavy bond or a substituted product thereof;
For example, dicarboxylic acids having a double bond such as maleic acid, butyl maleate, methyl maleate, dimethyl maleate and the like, and substituted products thereof; vinyl esters such as vinyl chloride, vinyl acetate and vinyl benzoate;
For example, ethylene-based olefins such as ethylene, propylene, butylene and the like;
Vinyl ketones such as vinyl hexyl ketone; vinyl ethers such as vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether and the like;
And the like, alone or in combination of two or more.

As the crosslinking agent, compounds having two or more polymerizable double bonds are mainly used, for example, aromatic divinyl compounds such as divinylbenzene and divinylnaphthalene; ethylene glycol diacrylate; Ethylene glycol dimethacrylate,
Carboxylic acid esters having two double bonds such as 1,3-butanediol dimethacrylate; divinyl compounds such as divinylaniline, divinyl ether, divinyl sulfide and divinyl sulfone; and compounds having three or more vinyl groups; Are used alone or as a mixture.

As the binder resin used in the present invention, the molecular weight distribution of the toner is a molecular weight distribution by GPC of a THF-soluble component, and has at least one peak in a molecular weight region of 3,000 to 50,000, At least 1 in more than 100,000 areas
And a component having a molecular weight of 100,000 or less is 50 to 9
It is preferable to use a binder resin having a concentration of 0%.

When the above-mentioned binder resin is used, even when the compound represented by the general formula (III) is used as a charge controlling agent, a satisfactory charge amount can be easily obtained.

Although this mechanism is not clear, it is considered as follows. In order that at least one peak exists in the region of 3,000 to 50,000 in the molecular weight distribution of the toner and the component having a molecular weight of 100,000 or less is 50 to 90%, the molecular weight distribution as the binder resin is also very small. Need something.
In order to reduce the molecular weight distribution, it is necessary to use a large amount of a polymerization initiator. This large amount of polymerization initiator may affect the charging of the toner. Further, since it contains a large amount of low molecular weight components, it is difficult for shear stress to be applied during kneading in the toner production process. In general, it is not preferable that the dispersion state of the charge control agent deteriorates, but the general formula (III)
In the compound represented by, the shear stress is weak,
Rather, it is considered that a dispersion state in which the charge amount tends to increase is created. If the peak does not exist in the region of 50,000 or less, not only good fixability is not obtained, but also the charge amount tends to decrease. If there is a peak of the low molecular weight component in a region smaller than 3,000, the shear stress becomes too weak, and the dispersion of the pigment or the like becomes worse. Molecular weight 1
When the weight fraction of less than or equal to 100,000 is less than 50%, the fixing property is deteriorated, the shear stress is increased, and the charge amount tends to be reduced. On the other hand, when the weight fraction of the molecular weight of 100,000 or less exceeds 90%, fixing offset tends to occur.

Since at least one peak exists in a region having a molecular weight of 100,000 or less, a fixing offset can be prevented even if a large amount of a low molecular weight component is contained as described above.

As a method of polymerizing the binder resin, it is preferable that the resin by solution polymerization accounts for 40% or more, and it is not preferable that the resin by suspension polymerization or emulsion polymerization be the main component in terms of the charge amount of the toner.

The coloring agents used in the present invention include carbon black, lamp black, iron black, ultramarine blue, nigrosine dye, aniline blue, phthalocyanine blue, phthalocyanine green, Hansa Yellow G and rhodamine 6
Conventionally known dyes and pigments such as G, chaco oil blue, chrome yellow, quinacridone, benzidine yellow, rose bengal, triarylmethane dyes, monoazo dyes and disazo dyes can be used alone or in combination.

Further, the toner of the present invention can be used as a two-component toner by mixing with a carrier. As the carrier, known carriers can be used, and examples thereof include iron powder, ferrite powder, powder having magnetic properties such as nickel powder, glass beads, and the like, and those obtained by treating the surfaces thereof with a resin or the like. . Further, as the resin for coating the carrier surface, styrene-acrylate copolymer, styrene-methacrylate copolymer, acrylate copolymer, methacrylate copolymer, silicone resin, fluorine-containing resin, A polyamide resin, an ionomer resin, a polyphenylene sulfide resin, or the like, or a mixture thereof can be used.

As the additives for imparting various properties used in the present invention, for example, the following are used.

1) Fluidity-imparting agent: metal oxide (silica,
Alumina, titania, etc.), carbon black, carbon fluoride, etc. Each of them has been subjected to hydrophobic treatment,
More preferred.

2) Abrasives: metal oxides (strontium titanate, cerium oxide, aluminum oxide, magnesium oxide, chromium oxide, etc.), nitrides (silicon nitride, etc.), carbides (silicon carbide, etc.), metal salts (calcium sulfate, etc.) , Barium sulfate, calcium carbonate).

3) Lubricants: fluororesin powder (vinylidene fluoride, polytetrafluoroethylene, etc.), fatty acid metal salt (zinc stearate, calcium stearate, etc.).

4) Charge controllable particles: metal oxides (such as tin oxide, titanium oxide, zinc oxide, silicon oxide, and aluminum oxide), carbon black, and spherical resin fine particles (average particle diameter 0.05 to 3 μm).

These additives are used in an amount of 0.05 to 10 parts by weight, preferably 0.1 to 5 parts by weight, based on 100 parts by weight of the toner particles. These additives are
They may be used alone or in combination.

Among the above additives, metal oxides for imparting fluidity will be described. In the present invention, in order to obtain proper positive chargeability and good developability, silica, alumina, or titania fine powder treated with a silane coupling agent and / or a silicone oil having a side chain containing a nitrogen atom is used. Preferably, the body is externally added.

The base silica fine powder to be treated includes anhydrous silicon dioxide (silica) as well as silicates such as aluminum silicate, sodium silicate, potassium silicate, magnesium silicate and zinc silicate. Applicable. Further, any of the production methods of the dry method and the wet method can be used.

In the toner of the present invention, it is more preferable to use positively-charged silica fine powder than negatively-charged silica fine powder as a silica fine powder to be added for preventing abrasion of the toner and preventing contamination of the sleeve surface. It is preferable without impairing the charging stability. In addition, the positively-charged silica refers to a silica having a positive triboelectric charging property when measured by a blow-off method.

As a method for obtaining the positively chargeable silica fine powder, the above-mentioned untreated silica fine powder is treated with a silicon oil having an organo group having at least one nitrogen atom in a side chain, or a nitrogen-containing silane. There is a method of treating with a coupling agent or a method of treating with both.

As the silicone oil having a nitrogen atom in the side chain, those having a structure represented by the formula (IV) can be generally used.

[0086]

Embedded image

(Wherein R ₁ and R ₆ are hydrogen, an alkyl group,
Represents an aryl group or an alkoxy group, R ₂ represents an alkylene group or a phenylene group, R ₃ represents a compound having a nitrogen-containing heterocyclic ring in its structure, R ₄ and R ₅ represent hydrogen,
Represents an alkyl group or an aryl group. Also, R ₂ may not be present. However, the above-mentioned alkyl group, aryl group, alkylene group and phenylene group may contain an amine, or may have a substituent such as halogen as long as the chargeability is not impaired. K is a number of 1 or more;
l, m, and n are positive numbers including 0. l + m + n is a positive number of 1 or more. The applied amount of these treated silica fine powders is effective when the amount is 0.01 to 20% based on the weight of the developer, and is particularly preferable when 0.03 to 5% is added. Shows positive chargeability having positive property. In a preferred embodiment of the addition form, 0.01 to 3% by weight of the treated silica fine powder based on the weight of the developer is preferably attached to the surface of the toner particles.

The silica fine powder used in the present invention may be treated with a silane coupling agent or a treating agent such as an organosilicon compound for the purpose of imparting hydrophobicity, if necessary. And treated with the above treating agent that reacts or physically adsorbs with the silica fine powder.

As the silane coupling agent used in the present invention, conventionally known silane coupling agents can be used.

For example, dimethyldichlorosilane, trimethylchlorosilane, allyldimethylchlorosilane, hexamethyldisilazane, allylphenyldichlorosilane,
Negatively charged ones such as benzyldimethylchlorosilane, vinyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, vinyltriacetoxysilane, divinylchlorosilane, dimethylvinylchlorosilane, and aminopropyltrimethoxysilane, aminopropyltrisilane Ethoxysilane, dimethylaminopropyltrimethoxysilane, diethylaminopropyltrimethoxysilane, dipropylaminopropyltrimethoxysilane,
Dibutylaminopropyltrimethoxysilane, monobutylaminopropyltrimethoxysilane, dioctylaminopropyltrimethoxysilane, dibutylaminopropyldimethoxysilane, dibutylaminopropylmonomethoxysilane, dimethylaminophenyltriethoxysilane, trimethoxysilyl gamma propylphenylamine, Such as trimethoxysilyl γ-propylbenzylamine, and further trimethoxysilyl γ-propylpiperidine;
A nitrogen-containing heterocyclic ring such as trimethoxysilyl γ-propylimidazole can be used.

It is also one of the preferable constitutions to use two kinds of treating agents, silicone oil (A) and silane coupling agent (B). These two types may be mixed in advance and treated at the same time, or may be treated with the treating agent (B) and then treated in the order of the treating agent (A). It is not preferable to treat the treating agent (B). Further, the treating agent (A) and the treating agent (B)
It is preferable that at least one of the above contains a nitrogen atom.

In the case where the silica particles are previously treated with the silicone oil, the silica fine powder agglomerates, and the treated silica particles are hard to be fine, so that the toner utilization may decrease.

Further, as the metal oxide fine powder used in the present invention, fine powders of titania and alumina are also preferable, and these may be used together, including silica fine powder.

Generally, when surface treatment is performed on silica fine powder, it is necessary to use a treating agent such as amino-modified silicone oil in order to achieve both hydrophobicity and positive chargeability.
However, oil-based treatment agents are difficult to treat uniformly,
"Dama" is formed and it is difficult to loosen fine particles. On the other hand, fine powders of titania and alumina are
Negative chargeability is not strong like silica fine powder. For this reason,
It is possible to achieve both hydrophobicity and chargeability without using an oil-based treating agent. Therefore, the fine powder of titania and alumina as the metal oxide fine powder can be easily disintegrated into fine particles, and can be obtained with less "dama". By using such titania fine powder in the present invention, the toner utilization rate is improved. Among the above metal oxide fine powders, BET
Preferably the base fine powder within the scope of the specific surface area by the measured nitrogen adsorption is 40 m ² / g or more (especially 50 to 400 m ² / g) by law, the treated fine powder, 3
Within the scope of 0 m ² / g or more (especially 70~350m ² / g) it is preferable.

When the amount of the metal oxide fine powder applied is 0.03 to 5% based on the weight of the developer, it exhibits excellent fluidity and stable chargeability.

Finally, when the treated metal oxide fine powder is hydrophobized to show a value of 30 or more as the degree of hydrophobicity measured by a methanol titration test, the friction of the toner is reduced. This is preferable because the charge amount becomes sharp and uniform and exhibits positive chargeability.

The “methanol titration test” defined in this specification for evaluating the degree of hydrophobicity of the metal oxide fine powder is performed as follows. 0.2 g of the test metal oxide fine powder is added to 50 ml of water in a 250 ml Erlenmeyer flask. Methanol is titrated from the buret until the entire amount of the metal oxide fine powder is wetted. At this time, the solution in the flask is constantly stirred with a magnetic stirrer. The end point is observed by the suspension of the entire amount of the metal oxide fine powder in the liquid, and the degree of hydrophobicity is expressed as the percentage of methanol in the liquid mixture of methanol and water at the end point.

In producing the toner according to the present invention, the above-mentioned toner constituting materials are sufficiently mixed by a ball mill or other mixer, and then kneaded well using a heat kneader such as a hot roll kneader or an extruder. A method of obtaining the toner by mechanical pulverization and classification after cooling and solidifying is preferable. Alternatively, a method of dispersing the constituent materials in a binder resin solution and then spray-drying to obtain the toner; A polymerized toner manufacturing method in which a predetermined material is mixed with a monomer to be constituted to form an emulsified suspension and then polymerized to obtain a toner; or a core material in a so-called microcapsule toner comprising a core material and a shell material. Alternatively, a method of including a predetermined material in the shell material or both of them can be applied. Further, if necessary, the desired additive is sufficiently mixed with a mixer such as a Henschel mixer to produce the toner according to the present invention.

In the measurement of the water content of the imidazole compound in the present invention, a sample of 0.5 ± 0.1 g is measured by a trace moisture measuring device (AQ-6 Hiranuma Sangyo Co., Ltd.).
The normal temperature and normal humidity environment is an environment controlled at 23 ° C./60±5% RH, and the high temperature and high humidity environment is 32.5 ° C./85±3% RH.
It is a controlled environment, and it is left in each environment for 3 days or more for measurement. Hydranal Aqualite RS was used as a titration reagent. The sample is heated by an automatic moisture vaporizer (SE-24 Hiranuma Sangyo Co., Ltd./110° C. setting, N ₂ gas 0.25 liter / min setting) connected to the AQ-6 through an interface.

In the present invention, the molecular weight distribution of the THF-soluble portion of the toner by GPC is measured under the following conditions. 40
The column is stabilized in a heat chamber at a temperature of ° C., and THF (tetrahydrofuran) as a solvent is flowed through the column at this temperature at a flow rate of 1 ml per minute, and about 100 μl of a THF sample solution is injected for measurement. In measuring the molecular weight of the sample, the molecular weight distribution of the sample was calculated from a calibration curve (the relationship between the logarithmic value of the molecular weight and the count number) prepared from several types of monodisperse polystyrene standard samples. As a standard polystyrene sample for preparing a calibration curve, for example, Tosoh Corporation or Showa Denko KK having a molecular weight of about 10 ² to 10 ⁷ , and it is appropriate to use at least about 10 standard polystyrene samples. . Also, the detector uses RI
A (refractive index) detector is used. As the column, it is preferable to combine a plurality of commercially available polystyrene gel columns. For example, a Shodex GPC KF manufactured by Showa Denko KK
-801, 802, 803, 804, 805, 806,
807,800P combination and TSK manufactured by Tosoh Corporation
gel G1000H (H _XL ), G2000H
(H _XL ), G3000H (H _XL ), G4000H
(H _XL ), G5000H (H _XL ), G6000H
(H _XL ), G7000H (H _XL ), TSKguardc
column can be mentioned.

The sample is prepared as follows.

After placing the sample in THF and leaving it to stand for several hours, it is shaken sufficiently, mixed well with THF (until the sample is no longer united), and left still for 12 hours or more. At this time TH
F is allowed to stand for at least 24 hours, and then the sample processing filter (pore size 0.45
0.5 μm, for example, Myshoridisk H-25-5
A sample passed through Tosoh, Exiclodisc 25CR (German Science Japan) can be used as a GPC sample. Further, the sample concentration is adjusted so that the resin component is 0.5 to 5 mg / ml.

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

Apparatus: GPC-150C (Waters) Column: GMH-HT 30 cm 2 columns (manufactured by Tosoh Corporation) Temperature: 135 ° C. Solvent: o-dichlorobenzene (addition of 0.1% ionol) Flow rate: 1.0 ml / min Sample: 0.4 ml of about 0.15% sample is injected

Measurement is performed under the above conditions, and the molecular weight of the sample is calculated using a molecular weight calibration curve prepared from a monodisperse polystyrene standard sample. In addition, Mark-Hou
It is calculated by converting to polyethylene using a conversion formula derived from the wink viscosity formula.

In the DSC measurement in the present invention, the measurement is performed by a differential scanning calorimeter of a high-precision internal heating type input correction type. For example, DSC-7 manufactured by PerkinElmer can be used.

The measurement is performed according to ASTM D3418-82. As the DSC curve used in the present invention, a DSC curve measured when the temperature is raised once, a pre-history is taken, and then the temperature is decreased and raised at a temperature rate of 10 ° C./min. The definition of each temperature is as follows.

Endothermic peak (positive direction is endothermic)

Peak rise temperature (LP): Temperature at which the peak curve is clearly deviated from the baseline. That is, the temperature at which the differential value of the peak curve is positive and the differential value starts to increase, or the temperature at which the differential value changes from negative to positive (a specific example is shown in FIG. 1).

Peak temperature (PP): Peak top temperature (maximum peak in a region of 120 ° C. or less)

Peak onset temperature (OP): P
At the point where the differential value of the peak curve of the peak that can be attributed to P becomes the maximum, a tangent to the curve is drawn, and the temperature at the intersection of the tangent and the baseline is shown (a specific example is shown in FIG. 1).

Heat generation peak (heat generation is in the minus direction)

Exothermic peak temperature: Peak top temperature

Intensity ratio of exothermic peaks: At the points where the differential value of the curve before and after the peak top of the above peak becomes a local maximum and a local minimum, draw a tangent to each curve, and let ΔT be the temperature difference between each tangent and the base line intersection. ΔH / ΔT when the height from the baseline to the peak top per weight is ΔH (the value of the measured peak height divided by the weight of the measurement sample, mW / mg) (a specific example in FIG. 2) That is, a larger value indicates that the peak is sharper.

In the present invention, the coefficient of variation of the particle size of the magnetic fine powder is measured as follows. The magnetic fine powder is well dispersed so that the overlap between the magnetic fine powders is reduced as much as possible, and a 30,000-fold photograph of a transmission electron microscope is taken in several fields without bias.

From here, 1,000 or more magnetic fine powders are randomly selected, and the diameter in the horizontal direction is measured. The coefficient of variation is the ratio of the standard deviation to the average diameter expressed in%.

In the present invention, the toner utilization rate is measured as follows. Before the copy test, the masses of the toner hopper, the developing device, and the cleaning unit are measured in advance. After the copy test, the mass is measured again, and the amount of consumed toner and the amount of toner collected in the cleaning unit are obtained, and are calculated by the following equation.

Toner utilization (%) = (1−recovered amount / consumed amount) × 100

The toner of the present invention can be used for development for visualizing an electrostatic image in electrophotography, electrostatic recording, electrostatic printing, and the like by a conventionally known means.

The toner containing the charge control agent according to the present invention has good triboelectric charging ability, and less contamination of the toner carrier such as the sleeve or carrier, so that the image quality does not deteriorate due to continuous copying. In addition, the color toner using the charge control agent of the present invention can provide a clear full-color image because there is no hindrance caused by the charge control agent.

[0121]

EXAMPLES The present invention will be described below in more detail with reference to Examples, which should not be construed as limiting the present invention.
All parts in the following formulations are parts by weight.

Example 1 Styrene-butyl methacrylate copolymer 100 parts Magnetite 60 parts Low molecular weight polypropylene wax 3 parts Compound example (1-1) 2 parts

After thoroughly mixing the above materials with a blender,
The mixture was kneaded with a twin-screw kneading extruder set at 150 ° C. After cooling the obtained kneaded material and coarsely pulverizing with a cutter mill,
Finely pulverize using a fine pulverizer using a jet stream, and divide the obtained fine powders simultaneously and strictly with a multi-segmentation classifier using the Coanda effect (Nippon Mining Co., Ltd. elbow jet classifier). After classification and removal, the weight average particle size is 11.3 μm.
m fine black powder was obtained.

To 100 parts of the obtained black fine powder, 0.4 part of positively charged hydrophobic silica (BET specific surface area: 200 m ^{2 /} g) treated with silicone oil having an amino group was added, and the mixture was mixed with a Henschel mixer. This was a chargeable one-component magnetic toner.

The obtained magnetic toner was transferred to a commercially available electrophotographic copying machine NP-3525 (manufactured by Canon Inc.) at 20,000 to 2,000.
A copy test of 00 sheets was performed. As a result, a clear image having an image density of 1.32 was obtained from the beginning. 20,000
The image after copying was also clear with a density of 1.35.
Further, when a copy test was conducted under a low temperature and a low humidity (15 ° C./10% RH), a clear image having an image density of 1.35 was obtained from the beginning, and a clear image having a density of 1.39 even after copying 20,000 sheets. And no deterioration in image quality was observed. Further, when a similar test was conducted in a severe environment of 35 ° C./80% RH, a good image having a density of 1.30 was obtained from the beginning, and the density was always 1.30 until after 20,000 sheets were copied.
33 or more clear images were obtained.

Example 2 Styrene-butyl acrylate-divinylbenzene copolymer 100 parts Magnetite 80 parts Low molecular weight polypropylene wax 4 parts Compound example (1-2) 5 parts

After mixing the above materials well in a blender,
The mixture was kneaded with a twin-screw kneading extruder set at 130 ° C. After cooling the obtained kneaded material and coarsely pulverizing with a cutter mill,
Finely pulverize using a fine pulverizer using a jet stream, and divide the obtained finely pulverized powder into fine powder and coarse powder at the same time using a multi-division classifier (elbow jet classifier manufactured by Nittetsu Mining Co., Ltd.) utilizing the Coanda effect. And the weight average particle size is 8.3 μm
Was obtained. Positively charged hydrophobic silica (BET specific surface area: 200 m ² / g) treated with dimethylaminopropyltrimethoxysilane on 100 parts of the obtained black fine powder
0.5 part was added and mixed with a Henschel mixer to obtain a positively chargeable one-component magnetic toner.

Using a commercially available electrophotographic copying machine NP-1215 (manufactured by Canon Inc.), a copy test of the obtained magnetic toner was performed.

As a result, a clear image having an image density of 1.34 was obtained from the beginning. The image after copying 20,000 sheets was also good with a density of 1.37. 35 ° C / 80
% RH, a clear image with a fog density of 1.31 was obtained from the beginning.
No deterioration in image quality was observed even after copying 000 sheets. Further, when a copy test was performed in an environment of 15 ° C./10% RH, a good image having a density of 1.36 was obtained from the beginning.
No deterioration in image quality was observed even after copying 20,000 sheets.

Comparative Example 1 A magnetic toner having a weight average diameter of 8.2 μm was obtained in the same manner as in Example 2 except that 3 parts of the following imidazole derivative was used instead of 3 parts of Compound Example (1-2). went.

[0131]

Embedded image

As a result, a clear image having a density of 1.34 was obtained from the beginning, and no deterioration of the image quality was recognized even after copying 20,000 sheets. However, when a copy test was performed in an environment of 35 ° C./80% RH, the image density was as low as 1.18. Further, a copying test was conducted up to 20,000 sheets, but the image density remained at around 1.1, and no increase in the image density was observed.

Comparative Example 2 A magnetic material having a weight average diameter of 8.1 μm was obtained in the same manner as in Example 2 except that 3 parts of a quaternary ammonium salt were used instead of 3 parts of the compound (1-2) used in Example 2. A toner was obtained and a copying test was performed.

As a result, the concentration was as low as 1.11 from the beginning,
After continuous copying of 20,000 sheets, an image having a sufficient density was not obtained.

Example 3 Styrene / butyl methacrylate copolymer 100 parts Copper phthalocyanine blue pigment 5 parts Low molecular weight polypropylene wax 2 parts Compound example (1-4) 4 parts

After thoroughly mixing the above materials with a blender,
The mixture was kneaded with a twin-screw kneading extruder set at 130 ° C. After cooling the obtained kneaded material and coarsely pulverizing with a cutter mill,
Finely pulverize using a fine pulverizer using a jet stream, and divide the obtained finely pulverized powder into fine powder and coarse powder at the same time using a multi-division classifier (elbow jet classifier manufactured by Nittetsu Mining Co., Ltd.) utilizing the Coanda effect. And a fine blue powder having a weight average particle size of 8.8 μm was obtained.

To 100 parts of the obtained fine blue powder, 0.6 part of dry silica (210 m ^{2 /} g) treated with N-diethylaminopropyltrimethoxysilane was mixed to obtain a toner.

Next, 5 parts of the obtained toner was mixed with 100 parts of a fluorine-acryl-coated ferrite carrier having an average particle diameter of 65 μm to prepare a developer.

This developer was used in a commercially available copying machine (trade name: NP-
5540, manufactured by Canon Inc.).

As a result, a bright blue image having a density of 1.35 was obtained. A vivid blue image having a density of 1.33 was obtained even after copying 10,000 sheets, and no deterioration in image quality was observed. Further, the uniformity of density in the solid image was also excellent.

Further, when an image was obtained in an environment of 35 ° C./80% RH, a clear image without fog having a density of 1.31 was obtained from the beginning, and deterioration of the image quality was observed even after copying 10,000 sheets. I couldn't. Further, when a copy test was performed in an environment of 15 ° C./10% RH, the density was 1.3 at the beginning.
3 good images were obtained, and no deterioration in image quality was observed even after copying 10,000 sheets.

Example 4 100 parts of a styrene / butyl methacrylate copolymer I. Pigment Red No. 22 4 parts Low molecular weight polypropylene wax 2 parts Compound example (1-5) 3 parts

Using the above materials, a red fine powder having a weight average particle size of 8.7 μm was obtained in the same manner as in Example 3.

Example 3 was added to 100 parts of the obtained red fine powder.
0.6 part of the dry silica used in the above was mixed to obtain a toner.

Next, a developer was obtained in the same manner as in Example 3, and a copy test was performed.

As a result, a bright red image having a density of 1.36 was obtained. A vivid red image with a density of 1.32 was obtained even after copying 10,000 sheets, and no deterioration in image quality was observed. Further, the uniformity of density in the solid image was also excellent.

When an image was obtained in an environment of 35 ° C./80% RH, a clear image without fog having a density of 1.32 was obtained from the initial stage, and deterioration of the image quality was observed even after copying 10,000 sheets. I couldn't. Further, when a copy test was performed in an environment of 15 ° C./10% RH, the density was 1.3 at the beginning.
5 good images were obtained, and no deterioration in image quality was observed even after copying 10,000 sheets.

Example 5 Styrene / butyl methacrylate copolymer 100 parts Copper phthalocyanine blue pigment 3 parts C.I. I. Pigment Yellow No. 81 1 part Low molecular weight polypropylene wax 3 parts Compound example (1-6) 5 parts

Using the above materials, a green fine powder having a weight average particle size of 8.1 μm was obtained in the same manner as in Example 3.

100 parts of the obtained green fine powder was mixed with 0.5 part of the dry silica used in Example 3 to obtain a toner.

Next, a developer was obtained in the same manner as in Example 3, and a copy test was performed.

As a result, a bright green image having a density of 1.36 was obtained. A vivid green image with a density of 1.32 was obtained even after copying 10,000 sheets, and no deterioration in image quality was observed. Further, the uniformity of density in the solid image was also excellent.

Further, when an image was obtained in an environment of 35 ° C./80% RH, a clear image without fog having a density of 1.31 was obtained from the beginning, and deterioration of the image quality was observed even after copying 10,000 sheets. I couldn't. When a copy test was performed in an environment of 15 ° C./10% RH, a good image having a density of 1.33 was obtained from the beginning, and no deterioration in image quality was observed even after copying 10,000 sheets.

Example 6 Styrene-acrylic copolymer 100 parts Copper phthalocyanine pigment 5 parts (CI pigment blue 15: 3) Compound example (1-1) 3 parts

After thoroughly mixing the above materials with a blender,
The mixture was kneaded with a twin-screw kneading extruder set at 130 ° C. The obtained kneaded material is cooled, coarsely pulverized, then finely pulverized using a fine pulverizer using a jet stream, and the obtained finely pulverized powder is subjected to a multi-segment classification apparatus utilizing the Coanda effect (Nippon Steel Mining Co., Ltd.) The ultrafine powder was strictly classified and removed at the same time by an elbow jet classifier (manufactured by EIZO Corporation) to obtain a fine powder having a weight average particle size of 8.3 μm.

To 100 parts of the obtained fine powder, 0.6 part of positively charged hydrophobic dry silica (BET specific surface area: 220 m ^{2 /} g) treated with dimethylaminopropyltrimethoxysilane was added, and the mixture was mixed with a Henschel mixer. The chargeable toner was used. Next, 4 parts of the obtained toner were mixed with 100 parts of a fluorine-acryl coated ferrite carrier having an average particle diameter of 65 μm to prepare a developer.

This developer was subjected to a copying test using a commercial color electrophotographic copying machine CLC-500 (manufactured by Canon Inc.) using a modified machine in which the OPC photosensitive drum was changed to an amorphous silicon drum.

As a result, a bright blue image having a density of 1.45 was obtained. A vivid blue image with a density of 1.43 was obtained even after copying 5,000 sheets, and no deterioration in image quality was observed. Further, the density uniformity of the solid image was excellent, and the reproducibility of halftone was also good. 35 ° C / 80%
When an image was obtained in an RH environment, a clear image without fog having a density of 1.48 was obtained, and no deterioration in image quality was observed even after copying 5,000 sheets. Furthermore, 15 ° C / 10%
When a copy test was performed in an environment of RH, the density was 1.4.
A good image of 0 was obtained, and no deterioration in image quality was recognized even after copying 5,000 sheets.

Example 7 The same as Example 6 except that 5 parts of the copper phthalocyanine pigment (CI Pigment Blue 15: 3) in Example 6 was changed to 1 part of a quinacridone pigment (CI Pigment Red 122). A fine powder having a weight average particle size of 8.2 μm was obtained, and the same silica as in Example 6 was mixed therewith to obtain a positively charged toner. Next, the same carrier as in Example 6 was mixed at the same ratio to obtain a developer.

This developer was subjected to a copy test in the same manner as in Example 6.

As a result, a vivid magenta image having a density of 1.45 was obtained. Even after copying 5,000 sheets, the density is 1.4.
6 bright blue images were obtained, and no deterioration in image quality was observed. Also, the density uniformity in solid images is excellent,
The halftone reproducibility was also good. 35 ° C /
When an image was obtained under an environment of 80% RH, the density was 1.49.
A clear image without fog was obtained, and no deterioration in image quality was recognized even after copying 5,000 sheets. In addition, 15 ° C /
When a copy test was performed in an environment of 10% RH, a good image having a density of 1.42 was obtained, and no deterioration in image quality was observed even after copying 5,000 sheets.

Example 8 5 parts of the copper phthalocyanine pigment (CI Pigment Blue 15: 3) in Example 6 was added to C.I. I. Pigment Yellow 17 was changed to 3.5 parts, and a fine powder having a weight average particle diameter of 8.5 μm was obtained in the same manner as in Example 6. Further, the same silica as in Example 6 was mixed to obtain a positively charged toner.

Next, the same carrier as in Example 6 was mixed at the same ratio to obtain a developer.

This developer was subjected to a copy test in the same manner as in Example 6.

As a result, a bright yellow image having a density of 1.41 was obtained. A vivid yellow image with a density of 1.43 was obtained even after copying 5,000 sheets, and no deterioration in image quality was observed. Further, the density uniformity of the solid image was excellent, and the reproducibility of halftone was also good. 35 ° C / 80%
When an image was obtained under a severe environment of RH, a clear image without fog having a density of 1.42 was obtained from the beginning, and
No deterioration in image quality was observed even after copying 0 sheets. further,
When a copy test was performed in an environment of 15 ° C./10% RH, a good image having a density of 1.36 was obtained from the beginning.
No deterioration in image quality was observed even after copying 000 sheets.

Example 9 A weight average particle diameter of 8.4 μm was obtained in the same manner as in Example 6, except that 5 parts of the copper phthalocyanine pigment (CI Pigment Blue 15: 3) in Example 6 was changed to 3 parts of carbon black.
And the same silica as in Example 6 was mixed to obtain a positively charged toner.

Next, the same carrier as in Example 6 was mixed at the same ratio to obtain a developer.

This developer was subjected to a copy test in the same manner as in Example 6.

As a result, a bright black image having a density of 1.48 was obtained. A vivid black image with a density of 1.47 was obtained even after copying 5,000 sheets, and no deterioration in image quality was observed. Further, the density uniformity of the solid image was excellent, and the reproducibility of halftone was also good. 35 ° C / 80%
When an image was obtained under a severe environment of RH, a clear image without fog having a density of 1.51 was obtained from the beginning, and
No deterioration in image quality was observed even after copying 0 sheets. further,
When a copy test was performed in an environment of 15 ° C./10% RH, a good image having a density of 1.43 was obtained from the beginning.
No deterioration in image quality was observed even after copying 000 sheets.

Example 10 When a full-color image was obtained using the toners of Examples 6 to 9, a good image having excellent color mixing properties and halftone reproducibility was obtained.

Example 11 Styrene / n-butyl methacrylate 100 parts Magnetite 80 parts Low molecular weight polypropylene wax 3 parts Compound example (2-1) 4 parts (water content at normal temperature and normal humidity: 1280 PPM / water content at high temperature and high humidity) : 2000 PPM / change rate: 156% / 180
℃, processed for 10 hours)

After mixing the above materials well in a blender,
The mixture was kneaded with a twin-screw kneading extruder set at 130 ° C. After cooling the obtained kneaded material and coarsely pulverizing with a cutter mill,
Finely pulverize using a fine pulverizer using a jet stream, and divide the obtained fine powders simultaneously and strictly with a multi-segmentation classifier using the Coanda effect (Nippon Mining Co., Ltd. elbow jet classifier). After classification and removal, the weight average particle size is 7.3 μm
Was obtained.

0.6 parts of silica fine powder treated with silicone oil having a primary amine in a side chain and the black fine powder 1
Was mixed with a Henschel mixer to obtain a positively chargeable one-component magnetic toner.

Using the above-mentioned magnetic toner, a copy test of 10,000 sheets was performed in a 32.5 ° C./85% RH environment using a modified electrophotographic copying machine NP-4835 (manufactured by Canon Inc.). As a result, a clear image without fogging was obtained at an image density of 1.37 from the beginning, and the image after copying 10,000 sheets was also a clear image having a density of 1.35. When the charge amount on the sleeve was measured after copying 10,000 sheets, it was 9.5 μC
/ G. At this time, there was no problem with filming or offset.

Next, a ghost image test was performed in an environment of 20 ° C./10% RH. As a result, a very good level of a weak ghost was observed only for one turn of the sleeve. The image density was 1.44.

Example 12 In Example 11, Compound Example (2-1) was replaced with Compound Example (2-6) (water content at normal temperature and normal humidity: 2300 PPM / water content at high temperature and high humidity: 4400 PPM / change rate: 191
%), Except that the weight average particle size is 7.6 μm.
Was obtained.

With respect to this magnetic toner, a copy test of 10,000 sheets was performed in an environment of 32.5 ° C./85% RH in the same manner as in Example 11. As a result, the image density was 1.33 from the beginning.
As a result, a clear image without fog was obtained, and the image after 10,000 copies was also clear with a density of 1.35. When the charge amount on the sleeve was measured after copying 10,000 sheets, it was 7.2.
μC / g. There was no problem with filming or offset.

Next, a ghost image test was conducted in an environment of 20 ° C./10% RH. As a result, weak ghosts were observed for three turns of the sleeve. The image density is 1.40.
Met.

Comparative Example 3 Compound Example (2-1) having a high water content was obtained (water content at normal temperature and normal humidity: 13000 PPM / water content at high temperature and high humidity: 14000 PPM / change rate: 108%). .

In Example 11, compound example (2-1)
Was replaced with the above compound to obtain a one-component magnetic toner having a weight average particle size of 7.8 μm.

With respect to this magnetic toner, a copy test of 10,000 sheets was performed in an environment of 32.5 ° C./85% RH in the same manner as in Example 11. As a result, the initial image density is 1.35.
However, the image density after 10,000 copies was as low as 1.15. Also, deposits on the photosensitive drum are generated,
Defects were seen in the image. When the charge amount on the sleeve was measured after copying 10,000 sheets, it was 5.1 μC / g. Further, when the stain of the web of the fixing unit was observed, it was larger than that in Example 11.

Comparative Example 4 In Example 11, 4 parts of Compound Example (2-1) was replaced with Compound Example (2-8) (water content at normal temperature and normal humidity: 50 PPM / water content at high temperature and high humidity: 160 PPM / change) (%: 320%) to obtain a one-component magnetic toner having a weight average particle size of 7.7 μm, except that the compound was replaced by 5 parts.

With respect to this magnetic toner, a copy test of 10,000 sheets was performed in an environment of 32.5 ° C./85% RH in the same manner as in Example 11. As a result, an image defect due to filming was found in a part of the image around the 6,000th sheet. Further, the image density after 10,000 sheets was as low as 1.15, and the charge amount on the sleeve was as low as 4.3 μC / g.

Example 13 100 parts of polyester 100 parts of carbon black 5 parts of compound example (2-5) 4 parts (water content at normal temperature and normal humidity: 1100 PPM / water content at high temperature and high humidity: 2500 PPM / change rate: 227%)

Using the above materials, a resin fine powder having a weight average diameter of 7.8 μm was obtained in the same manner as in Example 11. In addition, 2
The set temperature of the shaft kneader was 110 ° C. 10 parts of the obtained resin fine powder was mixed with 0.5 part of the silica fine powder used in Example 11.
Was mixed with 0.2 part of alumina fine powder to obtain a toner.

Next, 90 parts of an acrylic-coated ferrite carrier having an average particle diameter of 60 μm and 10 parts of the obtained toner were mixed to prepare a developer.

Using this developer, a copy test of 10,000 sheets was performed in a 32.5 ° C./85% RH environment using a two-component developing device of a commercially available electrophotographic copying machine NP-4835 (manufactured by Canon Inc.). went. As a result, the image density was 1.40 from the beginning.
Vivid black image was obtained, and the image after 10,000 copies was 1.4.
4 was clear. After 10,000 copies, the developer on the sleeve was sampled and the charge amount was measured. As a result, it was 15.0 μC / g. There was no problem with filming or offset.

Next, a copy test was performed in an environment of 15 ° C./10% RH, and a clear image having a density of 1.38 was obtained.

First, examples of synthesizing the magnetic material, the binder resin and the wax used in Examples 14 to 24 and Comparative Examples 5 to 7 described below will be described.

Synthesis Example 1-1 20 L of an aqueous ferrous sulfate solution containing 1.75 mol / L of Fe ²⁺ , 18 L of a 4N aqueous sodium hydroxide solution, 4 L of water, and 18.9 g of sodium silicate were used. A suspension containing 42 liters of Fe (OH) ₂ was prepared at 88 ° C. and pH 13.

The suspension containing Fe (OH) ₂ was heated to a temperature of 9 ° C.
The temperature was brought to 0 ° C., and 100 liters of air per minute was passed in for 2 hours to produce a black precipitate. The resulting particles were washed with water, separated by filtration, dried and pulverized. This is magnetite A.

Synthetic Example 1-2 Magnetites B and C were obtained from Synthetic Example 1-1 by changing the conditions of Fe ²⁺ concentration, pH and oxidation temperature.

Synthesis Example 2-1 80 parts of styrene 20 parts of n-butyl acrylate 20 parts of 2,2 bis (4,4-di-t-0.2 part of butylperoxycyclohexyl) propane These are polymerized by suspension polymerization. A was obtained.

Styrene 83 parts Butyl acrylate 17 parts Di-t-butyl peroxide 1.0 part

These were subjected to solution polymerization using xylene as a solvent to obtain a polymer B. Polymer A and polymer B were mixed with 30:
The solution was mixed at a weight ratio of 70 to obtain a binder resin 1.

Synthesis Example 2-2 80 parts of styrene 20 parts of n-butyl acrylate 20 parts of 2,2 bis (4,4-di-t-0.1 part of butylperoxycyclohexyl) propane These are polymerized by suspension polymerization. C was obtained.

Styrene 84 parts Butyl acrylate 16 parts Di-t-butyl peroxide 0.8 parts

These were subjected to solution polymerization using xylene as a solvent to obtain a polymer D. Polymer C and polymer D were 65:
The solution was mixed at a weight ratio of 35 to obtain a binder resin 2.

Synthesis Example 3-1 A wax was obtained by fractional crystallization of a hydrocarbon-based wax synthesized by the Age method.

Synthesis Example 3-2 Ethylene was polymerized at a low pressure using a Ziegler catalyst to obtain waxes B and C having relatively low molecular weights.

Example 14 Binder Resin 1 100 parts Magnetite A (average particle size 0.17 μm, variation coefficient 16%) 80 parts Wax A (Mn = 780, Mw = 1280) 3 parts Compound example (3-1) 5 Department

After thoroughly mixing the above materials in a blender,
The mixture was kneaded with a twin-screw kneading extruder set at 150 ° C. After cooling the obtained kneaded material and coarsely pulverizing with a cutter mill,
Finely pulverize using a fine pulverizer using a jet stream, and divide the obtained fine powders simultaneously and strictly with a multi-segmentation classifier using the Coanda effect (Nippon Mining Co., Ltd. elbow jet classifier). After classification and removal, the weight average particle size is 8.3 μm
Was obtained.

On the other hand, the temperature is maintained at about 250 ° C. while stirring 100 parts of silica fine powder (specific surface area: about 200 m ² / g) synthesized by a dry method. Silicone oil having a primary amine in the side chain is used as a treating agent. The silicone oil contains the following structure as a structural unit.

[0204]

Embedded image

30 parts of this treating agent was sprayed on the fine silica powder and treated for 30 minutes.

0.6 part of the treated silica fine powder and 100 parts of the black fine powder were mixed with a Henschel mixer to obtain a positively chargeable one-component magnetic toner.

Table 1 shows the GPC measurement result of the toner. Table 2 shows the DSC measurement result of the toner.
FIG. 1 shows a DSC curve at the time of temperature rise, and FIG. 2 shows a DSC curve at the time of temperature fall.

Using the above-mentioned magnetic toner, a commercially available electrophotographic copying machine NP-4835 (manufactured by Canon Inc.) was used.
A copy test of 30,000 sheets was performed in an environment of ° C / 80% RH. As a result, a clear image without fogging was obtained at an image density of 1.35 from the initial stage, and the image after copying 30,000 sheets also had a density of 1.35.
36 were clear. The image density after standing overnight in the middle did not fall below 1.25, and the number of sheets required to recover to 1.30 or more did not need to be 30 or more. When the charge amount on the sleeve was measured after copying 30,000 sheets, it was 7.5 μC / g.

Similarly, when a ghost image test was performed in an environment of 20 ° C./10% RH, a weak negative ghost was found to be at a very good level only for one round of the sleeve.

Example 15 A one-component magnetic toner was obtained in the same manner as in Example 14, except that Compound Example (3-1) was replaced with Compound Example (4-1). Table 1 shows the GPC measurement results of the toner.
Table 2 shows the SC measurement results.

A copy test of 30,000 copies of this magnetic toner was performed in an environment of 30 ° C./80% RH in the same manner as in Example 14. As a result, a clear image without fog was obtained at an image density of 1.38 from the beginning, and the image after copying 30,000 sheets was also a clear image having a density of 1.35. The image density after being left overnight in the middle does not fall below 1.25.
The number of sheets required to recover to 30 or more was not required. When the charge amount on the sleeve was measured after copying 30,000 sheets, it was 7.2 μC / g. The toner utilization during this period was 82%.

Similarly, when a ghost image test was conducted in an environment of 20 ° C./10% RH, a very good level of a weak negative ghost was observed only for one round of the sleeve.

When a fixing test of this toner was performed using a fixing tester having the same fixing device configuration as NP-4835, the non-offset region was 160 to 250 ° C.

Comparative Example 5 A one-component magnetic toner was obtained in the same manner as in Example 14, except that 5 parts of Compound Example (3-1) was replaced by 2 parts of nigrosine.

A copy test of 30,000 copies of this magnetic toner was performed in an environment of 30 ° C./80% RH in the same manner as in Example 14. As a result, the density of the image after copying 30,000 sheets was 1.
39, which was sufficient, but the initial image density was 1.3.
0, which was lower than that of Example 14. In some cases, the image density after standing overnight may be 1.10 or less.
It took 200 or more sheets to recover to zero or more.

Similarly, when a ghost image test was conducted in an environment of 20 ° C./10% RH, a positive ghost was observed for seven turns of the sleeve.

Example 16 In Example 15, magnetite A was replaced with magnetite B.
(Average particle diameter: 0.20 μm, variation coefficient: 27%) A one-component magnetic toner was obtained in the same manner, except that the average particle diameter was changed to 27%. Table 1 shows the GPC measurement result of this toner, and Table 2 shows the DSC measurement result.

A copy test of 30,000 copies of this magnetic toner was performed in an environment of 30 ° C./80% RH in the same manner as in Example 14. As a result, a clear image without fog was obtained at an image density of 1.35 from the beginning, and the image after copying 30,000 sheets was also a clear image having a density of 1.30. The image density after standing overnight in the middle does not fall below 1.20.
The number of sheets required to recover to 30 or more was not required to be 50 or more. When the charge amount on the sleeve was measured after copying 30,000 sheets, it was 6.6 μC / g.

Similarly, a ghost image test in an environment of 20 ° C./10% RH showed a very good level.

Comparative Example 6 In Example 15, magnetite A was replaced with magnetite C.
(Average particle diameter: 0.22 μm, coefficient of variation: 35%) A one-component magnetic toner was obtained in the same manner, except that the average particle diameter was changed to 35%.

A copy test of 30,000 copies of this magnetic toner was conducted in an environment of 30 ° C./80% RH in the same manner as in Example 14. As a result, an image having an image density as low as 1.23 was obtained from the beginning, and after copying 30,000 sheets, the image density was further reduced to 1.17. In the image density after being left for one night on the way,
It may be less than 00. When the charge amount on the sleeve was measured after copying 30,000 sheets, it was 5.0 μC / g.

Example 17 A one-component magnetic toner was obtained in the same manner as in Example 15, except that Binder Resin 1 was replaced with Binder Resin 2. Table 1 shows the GPC measurement results of this toner, and Table 2 shows the DSC measurement results.
Shown in

With respect to this magnetic toner, a copy test of 30,000 sheets was performed in an environment of 30 ° C./80% RH in the same manner as in Example 14. As a result, a clear image without fog was obtained at an image density of 1.39 from the beginning, and the image after copying 30,000 sheets was a clear image having a density of 1.30. The image density after standing overnight in the middle does not fall below 1.20.
The number of sheets required to recover to 30 or more was not required to be 50 or more. When the charge amount on the sleeve was measured after copying 30,000 sheets, it was 6.5 μC / g.

Similarly, a ghost image test in an environment of 20 ° C./10% RH showed a very good level.

Example 18 In Example 15, 3 parts of wax A was replaced with wax B
(Mn = 470, Mw = 1120) A one-component magnetic toner was obtained in the same manner except that 4 parts were used. As a result, fixability almost equivalent to that of Example 15 was obtained. D of this toner
Table 2 shows the SC measurement results.

With respect to this magnetic toner, a copy test of 30,000 sheets was performed in an environment of 30 ° C./80% RH in the same manner as in Example 14. As a result, a clear image without fog was obtained at an image density of 1.34 from the beginning, and the image after copying 30,000 sheets was also a clear image having a density of 1.32. The image density after standing overnight in the middle does not fall below 1.20.
The number of sheets required to recover to 30 or more was not required to be 50 or more. When the charge amount on the sleeve was measured after copying 30,000 sheets, it was 7.2 μC / g.

Similarly, a ghost image test in an environment of 20 ° C./10% RH showed a very good level.

Example 19 In Example 15, 3 parts of wax A was replaced with wax C.
(Mn = 750, Mw = 3200) A one-component magnetic toner was obtained in the same manner except that the amount was changed to 4 parts. As a result, a non-offset region substantially equal to that of Example 15 was obtained. Table 2 shows the DSC measurement result of this toner.

With respect to this magnetic toner, a copy test of 30,000 sheets was performed in an environment of 30 ° C./80% RH in the same manner as in Example 14. As a result, a clear image without fog was obtained at an image density of 1.36 from the beginning, and the image after copying 30,000 sheets was also a clear image having a density of 1.36. The image density after standing overnight in the middle does not fall below 1.20.
The number of sheets required to recover to 30 or more was not required to be 50 or more. When the charge amount on the sleeve was measured after copying 30,000 sheets, it was 7.1 μC / g.

Similarly, a ghost image test in an environment of 20 ° C./10% RH showed a very good level.

Example 20 A one-component magnetic toner was obtained in the same manner as in Example 14, except that Compound Example (3-1) was replaced with Compound Example (3-3).

With respect to this magnetic toner, a copy test of 30,000 sheets was performed in an environment of 30 ° C./80% RH in the same manner as in Example 14. As a result, a clear image without fog was obtained at an image density of 1.40 from the beginning, and the image after copying 30,000 sheets was also a clear image having a density of 1.36. The image density after standing overnight in the middle does not fall below 1.20.
The number of sheets required to recover to 30 or more was not required. When the charge amount on the sleeve was measured after copying 30,000 sheets, it was 7.7 μC / g.

Similarly, a ghost image test was conducted in an environment of 20 ° C./10% RH. As a result, the level of the negative ghost was good enough to be seen only for one turn of the sleeve.

Example 21 Binder Resin 1 100 parts C.I. I. Pigment Blue 15: 3 5 parts Wax A 3 parts Compound Example (3-1) 3 parts

Using the above materials, a resin fine powder having a weight average particle diameter of 8.6 μm was obtained in the same manner as in Example 14. To 100 parts of the obtained resin fine powder, 0.6 part of the silica fine powder used in Example 14 was mixed to obtain a toner.

Next, 95 parts of an acrylic-coated ferrite carrier having an average particle size of 50 μm and 5 parts of the obtained toner were mixed to prepare a developer.

Using a commercially available electrophotographic copying machine NP-4835 (manufactured by Canon Inc.), this developer was used at 30 ° C./8
A copy test of 10,000 sheets was performed in an environment of 0% RH. As a result, a clear image without fog was obtained at an image density of 1.34 from the beginning, and the image after copying 10,000 sheets was also a clear image having a density of 1.38.

Comparative Example 7 A developer was obtained in the same manner as in Example 21 except that Compound Example (3-1) was replaced with a quaternary ammonium salt of the following formula.

[0239]

Embedded image

A copy test was performed on this developer in the same manner as in Example 21. As a result, an image having a sufficient image density of 1.42 in the initial stage was obtained, but an image with noticeable fog was obtained. Thereafter, the toner was scattered around the time when the copying of about 5,000 sheets progressed, and as the copying progressed, the test was stopped.

Example 22 A fine black powder was obtained in the same manner as in Example 15.

On the other hand, the temperature is kept at about 250 ° C. while stirring the fine silica powder (specific surface area: about 200 m ² / g) synthesized by the dry method. Hexamethyldisilazane and the same silicone oil containing a primary amine as used in Example 14 are mixed 1/1 to obtain a treating agent. 30 parts of this treating agent was sprayed on 100 parts of the above silica fine powder and treated for 30 minutes.

The treated silica fine powder (0.6 part) and the black fine powder (100 parts) were mixed with a Henschel mixer to obtain a one-component magnetic toner.

With respect to this magnetic toner, a copy test of 30,000 sheets was conducted in an environment of 30 ° C./80% RH in the same manner as in Example 14. As a result, a clear image without fog was obtained at an image density of 1.37 from the beginning, and the image after copying 30,000 sheets was also a clear image having a density of 1.34. The image density after being left overnight in the middle does not fall below 1.25.
The number of sheets required to recover to 30 or more was not required. When the charge amount on the sleeve was measured after copying 30,000 sheets, it was 7.4 μC / g. The toner utilization during this period was 84%, which was higher than that of Example 15.

Similarly, a ghost image test was conducted in an environment of 20 ° C./10% RH. As a result, a very good level of a weak negative ghost was observed only for one turn of the sleeve.

Example 23 A one-component magnetic toner was obtained in the same manner as in Example 22, except that the treating agent for the silica fine powder was changed to 20 parts of dibutylaminotrimethoxysilane.

A copy test of 30,000 copies of this magnetic toner was performed in an environment of 30 ° C./80% RH in the same manner as in Example 14. As a result, a clear image without fog was obtained at an image density of 1.39 from the beginning, and the image after copying 30,000 sheets was also a clear image having a density of 1.36. The image density after being left overnight in the middle does not fall below 1.25.
The number of sheets required to recover to 30 or more was not required. When the charge amount on the sleeve was measured after copying 30,000 sheets, it was 7.7 μC / g. The toner utilization rate during this period was 85%, which was higher than that of Example 15.

Similarly, when a ghost image test was conducted in an environment of 20 ° C./10% RH, a weak negative ghost was found to be at a very good level only for one round of the sleeve.

Example 24 In Example 22, the treated fine silica powder was treated with 100 parts of titanium oxide and 25 parts of dibutylaminotrimethoxysilane (hydrophobicity: 55, specific surface area: 90 m).
^{2 /} g) A one-component magnetic toner was obtained in the same manner except that the amount was changed to 1.0 part.

With respect to this magnetic toner, a copy test of 30,000 sheets was performed in an environment of 30 ° C./80% RH in the same manner as in Example 14. As a result, a clear image without fog was obtained at an image density of 1.38 from the beginning, and the image after copying 30,000 sheets was also a clear image having a density of 1.34. The image density after being left overnight in the middle does not fall below 1.25.
The number of sheets required to recover to 30 or more was not required. When the charge amount on the sleeve was measured after copying 30,000 sheets, it was 7.0 μC / g. The toner utilization rate during this period was 86%, which was higher than that of Example 15.

Similarly, when a ghost image test was performed in an environment of 20 ° C./10% RH, a weak negative ghost was found to be at a very good level only by one round of the sleeve.

[0252]

[Table 1]

[0253]

[Table 2]

[0254]

As described above, the toner of the present invention has an appropriate charge amount very quickly and can maintain it in a high-temperature and high-humidity environment. A good image can be obtained over a long period of time from low humidity to high temperature and high humidity, and further, there is no damage to the copying machine body.

[Brief description of the drawings]

FIG. 1 is a diagram showing a DSC curve when a temperature of a toner of the present invention is raised.

FIG. 2 is a view showing a DSC curve when the temperature of the toner of the present invention is lowered.

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-3-101749 (JP, A) JP-A-2-87164 (JP, A) JP-A-3-72375 (JP, A) JP-A-1- 262555 (JP, A) JP-A-5-197192 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G03G 9/097 CA (STN)

Claims (8)

(57) [Claims] 1. A toner for developing an electrostatic charge image, comprising a binder resin containing at least two or more imidazole derivatives linked by a linking group having a conjugated system. 2. The electrostatic image developing toner according to claim 1, wherein the linking group is phenylene or propenylene. 3. The water content at normal temperature and normal humidity is 500 to 3000.
A toner for developing an electrostatic charge image, comprising an imidazole derivative which is a PPM and has a water content change rate of 250% or less under normal temperature and normal humidity conditions and high temperature and high humidity conditions. 4. The toner for developing an electrostatic image according to claim 3, wherein the imidazole derivative is a compound represented by the following general formula (I). Embedded image [Wherein R ₁ , R ₂ , R ₃ and R ₄ represent a hydrogen atom, an alkyl group, an aralkyl group or an aryl group, which may be the same or different, and each has a substituent. May be. X represents a linking group. ] 5. An electrostatic image developing toner comprising a compound represented by the following general formula (II). Embedded image [Wherein R ₁ , R ₂ , R ₃ and R ₄ represent a hydrogen atom, an alkyl group, an aralkyl group or an aryl group, which may be the same or different, and each has a substituent. May be. X represents a saturated linking group having 2 or more carbon atoms. ] 6. A toner for developing an electrostatic image, comprising a compound represented by the following general formula (III) and a magnetic fine powder, wherein the coefficient of variation of the particle size of the magnetic fine powder is 30% or less. . Embedded image [Wherein R ₁ , R ₂ , R ₃ and R ₄ represent a hydrogen atom, an alkyl group, an aralkyl group or an aryl group, which may be the same or different, and each has a substituent. May be. ] 7. The toner for developing an electrostatic image according to claim 5, further comprising a binder resin.
In the molecular weight distribution of soluble components by GPC (gel permeation chromatography), at least one peak exists in a region of a molecular weight of 3,000 to 50,000, and at least one peak exists in a region of a molecular weight of 100,000 or more. 10
A toner for developing an electrostatic image, wherein 50 to 90% of components of 10,000 or less are contained. 8. The composition according to claim 5, which contains a hydrocarbon wax.
The electrostatic image developing toner according to any one of claims 1 to 7,
In the DSC curve of the toner, (1) With respect to the endothermic peak at the time of temperature rise, the onset temperature at the endothermic peak is 120 ° C. or less, the endothermic peak temperature is in the range of 100 to 130 ° C., and (2) Regarding the exothermic peak, the exothermic peak temperature is 6
A toner for developing an electrostatic image, which is in the range of 2 to 80 ° C.