JPH06289645A - Electrostatic charge image developing toner and production of resin composition for the same - Google Patents

Abstract

PURPOSE:To improve dispersibility of wax in a toner and to obtain high picture quality while satisfying fixing property and antioffset property by controlling the state of the wax in a toner resin compsn. CONSTITUTION:At least a binder resin and wax 52 are molten or dissolved and mixed to obtain a resin compsn. 51 for a toner. This compsn. and at least a coloring agent are kneaded and pulverized to obtain an electrostatic charge image developer. In the resin compsn. 51 for the toner, the wax 52 is dispersed to form rod-like or acicular (linear) domains. By forming rod-like or acicular (linear) domains of the wax, namely by deforming domains while the volume distribution of domains is not much changed, domains of the wax can be easily sheared in the process of neadding with the toner as the next process. It is preferable that the diameter of domains (spherical) of the wax before deformed into rod-like or acicular (linear) domains is fine and uniform.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a resin composition for an electrophotographic toner and a developer for developing an electrostatic image using the resin composition for a toner.

[0002]

2. Description of the Related Art Conventionally, as an electrophotographic method, US Pat. No. 2,297,691 and JP-B-42-23910 are known.
Although many methods are known as described in JP-B No. 43-24748 and Japanese Patent Publication No. 43-24748, generally, a photoconductive substance is used and an electric latent image is formed on a photoreceptor by various means. And then developing the latent image with toner,
After transferring the toner image to a transfer material such as paper, if necessary,
The toner is fixed by heat, pressure, heat and pressure, or solvent vapor to obtain a copy, and the toner remaining on the photoreceptor without being transferred is cleaned by various methods, and the above steps are repeated.

In recent years, such a copying apparatus has begun to be used not only as a general-purpose copying machine for copying original documents but also as a printer as an output of a computer or a personal copy for individuals. .

[0004] Therefore, smaller size, lighter weight, higher speed, and higher reliability have been rigorously pursued, and machines have come to be composed of simpler elements in various respects. As a result, the performance required for the toner has become higher, and if the improvement in the performance of the toner cannot be achieved, a better machine cannot be established.

For example, various methods and apparatuses have been developed for fixing a toner image on a sheet such as paper. For example, there are a pressure heating method using a heat roller and a heat fixing method in which a heating member is brought into close contact with a heating member via a film.

In the heating method using a heating roller or a film, fixing is carried out by passing the toner image surface of the sheet to be fixed in contact with the surface of the heating roller or the film whose surface is formed of a material having releasability for toner. Is to do. In this method, since the surface of the heat roller or the film comes into contact with the toner image on the sheet to be fixed, the thermal efficiency at the time of fusing the toner image on the sheet to be fixed is extremely good, and the fixing can be performed quickly. , Very effective in electrophotographic copying machines. However, in the above method, since the toner image is in contact with the heat roller or the film surface in a molten state, a part of the toner image adheres to and is transferred to the fixing roller or the film surface, and is retransferred to the next sheet to be fixed. A so-called offset phenomenon may occur and the sheet to be fixed may be soiled. It is one of the essential conditions of the heat fixing method to prevent the toner from adhering to the heat fixing roller or the film surface.

Conventionally, for the purpose of preventing the toner from adhering to the surface of the fixing roller, for example, the roller surface is formed of a material excellent in releasability from the toner, such as silicone rubber or fluorine resin, and the surface is prevented from offsetting and In order to prevent fatigue of the roller surface, the roller surface is coated with a thin film of a liquid having a good releasing property such as silicone oil. However, this method is extremely effective in preventing toner offset, but has a problem that the fixing device becomes complicated because an apparatus for supplying the offset preventing liquid is required.

This is in the opposite direction to the reduction in size and weight, and moreover, silicone oil or the like may evaporate due to heat and pollute the inside of the machine. Therefore, instead of using a silicone oil supply device, instead of supplying an offset prevention liquid from the toner during heating, we proposed a method of adding a release agent such as low molecular weight polyethylene or low molecular weight polypropylene to the toner. Has been done. If a large amount of such an additive is added in order to obtain a sufficient effect, filming on the photoreceptor or the surface of a toner carrier such as a carrier or a sleeve is contaminated, and an image is deteriorated, which is a practical problem. Therefore, a device in which a small amount of a releasing agent is added to the toner to such an extent that the image is not deteriorated and a small amount of releasing oil is supplied or the offset toner is cleaned by a winding type device using a member such as a web. Are used in combination.

However, considering recent demands for size reduction, weight reduction, and high reliability, it is necessary to remove even these auxiliary devices, which is preferable. Therefore, if there is no further performance improvement such as toner fixing, offset, etc.
It is difficult to realize it without further improvement of the binder resin and release agent of the toner.

It is known to include a wax as a releasing agent in the toner. For example, JP-A-52-330
4, JP-A-52-3305, JP-A-57-
Techniques such as Japanese Patent No. 52574 are disclosed.

Further, JP-A-3-50559, JP-A-2-79860, JP-A-1-109359, JP-A-62-14166, and JP-A-61-27.
3554, JP 61-94062, JP 61-138259, JP 60-25236.
1, JP-A-60-252360, JP-A-6
A technique for containing waxes is disclosed in, for example, 0-217366.

Waxes are used for improving the offset resistance of the toner at low temperature and high temperature, and for improving the fixing property at low temperature. However, many of these are insufficient in terms of sufficiently dispersing the wax, and their development is required.

On the other hand, for example, as a method for producing a resin composition for a toner, in JP-A-64-15754, a polyolefin polymer is dispersed and mixed in a vinyl polymer solution, heated and then flushed to a vacuum system. However, according to this method, the process becomes complicated, and the wax dispersibility in the resin when the toner is produced by using this resin and kneading and pulverizing is still insufficient. .

That is, a binder having a low melt viscosity characteristic and a wax having a low melting point have been used in accordance with the low temperature fixing property of a toner which has been recently demanded. In this case, it is necessary to highly disperse the wax. In the prior art, it is difficult to maintain a high image quality while satisfying the high fixability and anti-offset property, and further, the storage stability is deteriorated. If the dispersibility of the wax is insufficient as the toner becomes finer, the fluidity of the toner is significantly deteriorated, which causes a problem that high image quality (dot reproducibility) cannot be achieved.

Further, Japanese Patent Application Laid-Open No. 56-87051 discloses a method of polymerizing a resin for toner in the presence of an offset preventive agent. However, the wax affects the degree of polymerization of the resin, the molecular weight, etc. In addition, there are drawbacks such as reduced releasability.

Further, as a method of adding waxes to the binder resin in advance, for example, JP-A-62-1
95683, JP-A-3-185458, JP-A-56.
-87051, JP-A-2-2578, JP-A2-1
It is disclosed in Japanese Patent No. 2160.

According to this method, a toner composed of a binder resin having a narrow molecular weight distribution is expected to have good dispersion and improved offset resistance. However, in order to apply it to low temperature fixability and offset resistance at high temperature, the binder is highly applicable. It is necessary to widen the molecular weight distribution of the resin, the worse the compatibility of the low molecular weight component and the high molecular weight component, the worse the dispersibility of the wax component, and it is not enough to disperse the wax in the binder resin in advance. Becomes

[0018]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for producing a resin composition for a toner and a developer for developing an electrostatic image, which solves the above problems.

That is, an object of the present invention is to provide a resin for toner which has excellent anti-offset property and enables high speed copying machines and LBPs (laser beam printers), low temperature fixing, and high image quality maintenance. It is intended to provide a method for producing a composition and a developer for developing an electrostatic image.

Further, an object of the present invention is to provide a method for producing a resin composition for a toner capable of producing a toner having excellent storage stability and fluidity of the toner and excellent reproducibility of image quality (dot reproducibility), and an electrostatic charge image. To provide a developer for development.

[0021]

Means and Actions for Solving the Problems The present inventors have
The present invention has been completed by finding that the performance of the toner kneaded and pulverized using this resin is changed by controlling the presence state of wax in the toner resin composition.

That is, the present invention relates to a developer for electrostatic charge image development obtained by kneading and pulverizing at least a colorant and a resin composition for toner obtained by melting or dissolving and mixing at least a binder resin and a wax. The present invention relates to a developer for developing an electrostatic charge image, wherein a wax domain shape in the toner resin composition is dispersed in a rod shape or a needle shape (linear shape).

Furthermore, the present invention is a method for producing a resin composition for a toner containing at least a binder resin and a wax, wherein at least the binder resin and the wax are melted or melt mixed, and then the domain shape of the wax is substantially spherical. The present invention relates to a method for producing a resin composition for toner, which comprises a step of deforming the resin composition into a rod shape or a needle shape (linear shape).

The present invention will be further described in detail.

The wax domain in the resin composition of the present invention is made into a rod shape or a needle shape (linear shape), and then mixed with other toner constituents and kneaded to improve the dispersibility of the wax. The reason why the toner characteristics are improved is presumed as follows.

Usually, the domain shape of the wax obtained by mixing the wax in the resin is substantially spherical or elliptical. Furthermore, when the resin component has a poor compatibility with the wax, or when the resin has a wide molecular weight distribution, the particle size distribution of the wax domain particle tends to be broad and coarse.

In order to uniformly disperse the wax in the poorly compatible resin, it is effective to control the volume of the domain, that is, the particle size in the case of a spherical shape, but the second additive is required. However, the process is complicated, and many restrictions are imposed, and the resin and the wax itself are limited.

The inventors of the present invention have a step of forming the wax domain shape into a rod shape or a needle shape (linear shape), that is, by changing the shape of the wax domain volume distribution without changing so much that the next step is performed. It was found that the wax domain is easily sheared in the toner kneading step.

That is, first, when the shape of the wax domain is changed from spherical to rod-like or needle-like (linear), the particle size as the diameter (minor diameter) is remarkably reduced, and the distribution thereof is also narrowed. , Secondly, it becomes more finer than the shearing property when the shearing force of the same shear is applied to the spherical domain of the same volume by being rod-shaped or needle-shaped (linear) Is presumed to allow more uniform wax dispersion.

The preferred wax domain size in the present invention is such that the minor axis of the wax is 20 μm or less, more preferably 10 μm or less, and even more preferably 5 μm or less.

Further, the relationship between the minor axis and the major axis of the rod-shaped or needle-shaped (linear) domain is such that the major axis is 5 times or more, preferably 10 times or more, more preferably 20 times or more the minor axis. It is desirable to deform it.

When the minor axis of the wax domain exceeds 20 μm, the dispersibility at the time of kneading is slightly inferior even if the shape is a rod (however, the dispersibility is better than that of a spherical wax domain having the same volume).

That is, in order to meet the recent demand for finer toner particles (toner weight average particle diameter of 7 μm or less),
It becomes insufficient to secure the fluidity of the toner and achieve high image quality.

If the major axis is less than 5 times the minor axis due to the relationship between the minor axis of the wax domain and the major axis, the shearing property at the time of melt kneading at the time of toner production becomes insufficient.

Further, in the present invention, it is preferable that the diameter (spherical shape) of the domain before being deformed into a rod shape or a needle shape (linear shape) is fine and uniform. It is easy to exert the effect of.

The production method of the present invention is characterized by including a step of melting or melting and mixing a binder resin and wax, and then changing the domain shape of the wax from spherical to rod-like or needle-like (linear). The method for deforming the domain shape in the resin can be achieved by stretching a mixture of the binder resin and wax in a molten state into a plate shape, a film shape, or a transition shape. Preferably, it is a plate or film and is preferably stretched and formed to a thickness of 5 mm or less, preferably 3 mm or less. At this time, the shape and the size thereof are controlled by the melt viscosity, the temperature, the drawing pressure, and the speed.

FIG. 5 shows an observation example B of the dispersed state (shape) of the wax in the resin composition of the present invention obtained by the above method. It can be seen that the wax 52 exists in the resin 51 in a state of being deformed into a rod shape or a needle shape (linear shape).

The binder resin and the wax of the present invention can be mixed by dissolving and mixing in the presence of an organic solvent, or by dry-mixing and then melting and kneading. In the case of a resin obtained by a polymerization method using a solvent, a method may be mentioned in which a wax is mixed at the end of the polymerization and then the solvent is removed.

The binder resin used in the present invention is preferably one having both a low molecular weight component and a high molecular weight component from the viewpoint of achieving both low temperature fixability and offset resistance. Examples of the production method include a method of obtaining by a two-step polymerization method, a method of separately producing resins of a low molecular weight component and a high molecular weight component, and blending the same.

The binder resin contains substantially no tetrahydrofuran (THF) insoluble matter (5 wt% or less), and
GP of high molecular weight and low molecular weight components measured by F soluble content
A combination in which the molecular weight peak in the molecular weight distribution by C has a peak of the high molecular weight component in a molecular weight region 50 times or more that of the low molecular weight component is preferable. When the peak ratio of the low molecular weight polymer and the high molecular weight polymer is less than 50 times, the offset resistance is deteriorated and the non-offset area is reduced.

Further, as a preferable molecular weight distribution of the binder resin used in the present invention, the molecular weight distribution by GPC is 3 × 10.
^{3 to} 5 × 10 ⁴ , more preferably 3 × 10 ^{3 to} 3 × 10
There are at least one peak in the region of ⁴ and 3 × 10
Another peak is present at ⁵ or more (more preferably 5 × 10 ⁵ or more), and a component of 3 × 10 ⁵ or less is preferably 50% or more, more preferably 60% or more. More preferably, the high molecular weight component has a weight average molecular weight of 1.0 × 10 ⁶ or more and a low molecular weight component. When the binder resin is constituted in the above-mentioned molecular weight distribution range, it becomes possible to highly attain low-temperature fixability and offset resistance. Further, the weight average molecular weight (Mw) / number average molecular weight (Mn) is preferably 30 or more.

When there is a considerable difference in the molecular weight between the low molecular weight component and the high molecular weight component, the conventional wax dispersion technique is likely to cause a problem, but by introducing the present invention, the effect of the present invention is most excellent. Reflected.

Regarding the binder containing such a high molecular weight component, it is more preferable to premix the high molecular weight component and the wax in advance and then mix the low molecular weight component in order to improve the mixing property.

As the binder resin used in the toner resin composition of the present invention, the following binder resins can be used.

For example, polystyrene, a homopolymer of styrene such as polystyrene, poly-p-chlorostyrene, polyvinyltoluene, and the like, and a substitution product thereof; styrene-p-chlorostyrene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene. Copolymer, styrene-acrylic acid ester copolymer, styrene-methacrylic acid ester copolymer, styrene-α-chloromethyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-
Styrene such as vinyl methyl ether copolymer, styrene-vinyl ethyl ether copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile-indene copolymer -Based copolymer; polyvinyl chloride, phenol resin, natural modified phenol resin, natural resin modified maleic acid resin, acrylic resin, methacrylic resin, polyvinyl acetate, silicone resin, polyester resin, polyurethane, polyamide resin, furan resin, epoxy resin , Xylene resin, polyvinyl butyral, terpene resin, coumarone indene resin, petroleum resin and the like can be used. Preferred binder materials include styrene copolymers and polyester resins.

Examples of the comonomer for the styrene monomer of the styrene copolymer include acrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate,
Dodecyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, phenyl acrylate, methacrylic acid, methyl methacrylate, ethyl methacrylate, butyl methacrylate, octyl methacrylate, octyl methacrylate, acrylonitrile, methacrylonitrile, acrylamide, etc. Dicarboxylic acids having a heavy bond and substituted compounds thereof; vinyl esters such as vinyl chloride, vinyl acetate, vinyl benzoate and the like; for example ethylene, propylene,
Ethylenic olefins such as butylene; vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone; vinyl ethers such as vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether; vinyl monomers such as Are used alone or in combination of two or more.

The styrene polymer or styrene copolymer may be crosslinked or may be a mixed resin.

As the cross-linking agent for the binder resin, a compound mainly having two or more polymerizable double bonds may be used. For example, aromatic divinyl compounds such as divinylbenzene and divinylnaphthalene; carboxylic acid esters having two double bonds such as ethylene glycol diacrylate, ethylene glycol dimethacrylate and 1,3-butanediol dimethacrylate; Divinyl compounds such as divinylaniline, divinyl ether, divinyl sulfide, divinyl sulfone; and 3
A compound having at least one vinyl group; is used alone or as a mixture.

In the bulk polymerization method, a low molecular weight polymer can be obtained by increasing the termination reaction rate by polymerizing at a high temperature, but there is a problem that the reaction is difficult to control.
In the solution polymerization method, a low molecular weight polymer can be easily obtained under mild conditions by utilizing the difference in radical chain transfer depending on the solvent, and by adjusting the amount of the initiator and the reaction temperature. It is preferred when low molecular weight products are obtained in the composition.

As the solvent used in the solution polymerization, xylene, toluene, cumene, cellosolve acetate, isopropyl alcohol, benzene and the like can be used. In the case of a styrene monomer mixture, xylene, toluene or cumene are preferred. It is appropriately selected depending on the polymer to be polymerized.
The reaction temperature varies depending on the solvent used, the initiator, and the polymer to be polymerized, but is preferably 70 ° C to 230 ° C. The solution polymerization is preferably carried out with 30 parts by weight to 400 parts by weight of the monomer per 100 parts by weight of the solvent.
Furthermore, it is also preferable to mix another polymer in a solvent at the end of the polymerization, and several polymers can be mixed well.

As a polymerization method for obtaining a high molecular weight component or a gel component, an emulsion polymerization method or a suspension polymerization method is preferable.

Among them, the emulsion polymerization method is a method in which a monomer (monomer) almost insoluble in water is dispersed as small particles in an aqueous phase with an emulsifier, and polymerization is performed using a water-soluble polymerization initiator. . In this method, it is easy to control the heat of reaction, and the phase in which the polymerization takes place (oil phase consisting of polymer and monomer)
And the aqueous phase are different, the termination reaction rate is low, and as a result, the polymerization rate is high and the polymerization degree is high. Further, in the production of toner, due to the relatively simple polymerization process and the fine particles of the polymerization product,
It is advantageous as compared with other methods as a method for producing a binder resin for a toner, because it can be easily mixed with a colorant, a charge control agent and other additives.

However, the suspension polymerization is a simple method because the produced polymer is apt to become impure due to the added emulsifier and an operation such as salting out is required to take out the polymer.

In suspension polymerization, 100 parts by weight or less of the monomer (preferably 1 part by weight) is added to 100 parts by weight of the aqueous solvent.
0 to 90 parts by weight) is preferable. As the dispersant that can be used, polyvinyl alcohol, partially saponified polyvinyl alcohol, calcium phosphate, etc. are used, and there is an appropriate amount such as the amount of monomers in the aqueous solvent, but generally 0.05 to 1 per 100 parts by weight of the aqueous solvent. Used in parts by weight. The polymerization temperature is suitably 50 to 95 ° C., but it should be appropriately selected depending on the initiator used and the target polymer. As the initiator type, any initiator that is insoluble or sparingly soluble in water can be used.

As the initiator to be used, t-butylperoxy-2-ethylhexanoate, cumin perpivalate, t-butylperoxylaurate, benzoyl peroxide, lauroyl peroxide, octanoyl peroxide, di- -T-butyl peroxide, t
-Butyl cumyl peroxide, dicumyl peroxide, 2,2'-azobisisobutyronitrile, 2,2 '
-Azobis (2-methylbutyronitrile), 2,2'-
Azobis (2,4-dimethylvaleronitrile), 2,
2'-azobis (4-methoxy-2,4-dimethylvaleronitrile), 1,1-bis (t-butylperoxy)
3,3,5-Trimethylcyclohexane, 1,1-bis (t-butylperoxy) cyclohexane, 1,4-bis (t-butylperoxycarbonyl) cyclohexane, 2,2-bis (t-butylperoxy) Octane,
n-butyl 4,4-bis (t-butylperoxy) valerate, 2,2-bis (t-butylperoxy) butane, 1,3-bis (t-butylperoxy-isopropyl) benzene, 2,5 -Dimethyl-2,5-di (t-butylperoxy) hexane, 2,5-dimethyl-2,5
-Di (t-butylperoxy) hexane, 2,5-dimethyl-2,5-di (benzoylperoxy) hexane,
Di-t-butyldiperoxyisophthalate, 2,2-
Bis (4,4-di-t-butylperoxycyclohexyl) propane, di-t-butylperoxy α-methylsuccinate, di-t-butylperoxydimethyl glutarate, di-t-butylperoxyazelate , 2, 5
-Dimethyl-2,5-di (t-butylperoxy) hexane, diethylene glycol-bis (t-butylperoxycarbonate), di-t-butylperoxytrimethyl adipate, tris (t-butylperoxy) triazine, vinyl tris Examples thereof include (t-butylperoxy) silane, and these can be used alone or in combination. The amount used is 100 parts by weight of the monomer,
0.05 parts by weight or more (preferably 0.1 to 15 parts by weight)
Used at a concentration of.

In the present invention, the initiator used in the synthesis of the high molecular weight polymer may be any one which is insoluble or hardly soluble in water. For example, benzoyl peroxide or tert-butyl. Peroxyhexanoate or the like is used alone or in combination in an amount of 0.05 to 0.5 parts by weight with respect to 100 parts by weight of the monomer.

In the present invention, a polyfunctional polymerization initiator having a polyfunctional structure is particularly preferable.

Specific examples of the polyfunctional polymerization initiator include:
1,1-di-t-butylperoxy-3,3,5-trimethylcyclohexane, 1,3-bis- (t-butylperoxyisopropyl) benzene, 2,5-dimethyl-
2,5- (t-butylperoxy) hexane, 2,5-
Dimethyl-2,5-di- (t-butylperoxy) hexyne-3, tris- (t-butylperoxy) triazine, 1,1-di-t-butylperoxycyclohexane, 2,2-di-t -Butyl peroxybutane, 4,4
-Di-t-butylperoxyvaleric acid-n-
Butyl ester, di-t-butyl peroxyhexahydroterephthalate, di-t-butyl peroxyazelate, di-t-butyl peroxytrimethyl adipate, 2,2-bis- (4,4-di-t-butyl) Peroxycyclohexyl) propane, 2,2-t-butylperoxyoctane, and various polymer oxides, etc. A polyfunctional polymerization initiator having a functional group having a polymerization initiation function such as two or more peroxide groups in one molecule. , And diallyl peroxy dicarbonate, t-butyl peroxy maleic acid, t-butyl peroxy allyl carbonate and t-butyl peroxy isopropyl fumarate.
It is selected from polyfunctional polymerization initiators having both a functional group having a polymerization initiation function such as a peroxide group and a polymerizable unsaturated group in the molecule.

Of these, preferred are 1,1-di-t-butylperoxy-3,3,5-trimethylcyclohexane, 1,1-di-t-butylperoxycyclohexane and di-t-butyl. Peroxyhexahydroterephthalate, di-t-butylperoxyazelate and 2,2-bis- (4,4-di-t-butylperoxycyclohexyl) propane, and t-butylperoxyallyl carbonate.

These polyfunctional polymerization initiators can be used alone or in combination, but in order to satisfy various performances required as a binder for toner, they are used in combination with a monofunctional polymerization initiator. Preferably. In this case, the monofunctional polymerization initiator is selected from those having a decomposition temperature lower than the decomposition temperature for obtaining the half-life of 10 hours of the polyfunctional polymerization initiator used in combination.

Specifically, benzoyl peroxide,
1,1-di (t-butylperoxy) -3,3,5-trimethylcyclohexane, n-butyl-4,4-di (t
-Butylperoxy) valerate, dicumyl peroxide, α, α'-bis (t-butylperoxydiisopropyl) benzene, t-butylperoxycumene, di-t
Organic peroxides such as butyl peroxide, azo and diazo compounds such as azobisisobutyronitrile and diazoaminoazobenzene can be used.

These monofunctional polymerization initiators may be added to the monomer at the same time as the polyfunctional polymerization initiator, but in order to keep the initiator efficiency of the polyfunctional polymerization initiator proper. It is preferably added after the polymerization time has passed the half-life indicated by the polyfunctional polymerization initiator under arbitrary polymerization conditions.

Further, it is preferable to add a crosslinkable monomer to the peak component on the polymer side.

As the crosslinkable monomer, a monomer having two or more polymerizable double bonds is mainly used.

The binder resin used in the present invention must be a polymer crosslinked with a crosslinking monomer as exemplified below in order to achieve the object of the present invention to a higher degree.

Aromatic divinyl compounds such as divinylbenzene, divinylnaphthalene and the like; diacrylate compounds linked by an alkyl chain; for example, ethylene glycol diacrylate, 1,3-butylene glycol diacrylate, 1,4-butanediol. Diacrylate,
1,5-Pentanediol diacrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, and compounds obtained by replacing the acrylates of the above compounds with methacrylates; diacrylate compounds linked by an alkyl chain containing an ether bond. , Such as diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol # 400 diacrylate, polyethylene glycol # 600 diacrylate, dipropylene glycol diacrylate, and the acrylates of the above compounds replaced with methacrylate Diacrylate compounds linked by a chain containing an aromatic group and an ether bond, for example, polyoxyethylene (2) -2,2-bis ( - hydroxyphenyl) propane diacrylate, polyoxyethylene (4) -2,
2-bis (4-hydroxyphenyl) propane diacrylate, and those obtained by replacing the acrylate of the above compounds with methacrylates; further, polyester type diacrylate compounds, for example, trade name MANDA (Nippon Kayaku) . As the polyfunctional crosslinking agent, pentaerythritol acrylate, trimethylolethane triacrylate, trimethylolpropane triacrylate, tetramethylolpropane triacrylate, tetramethylolmethane tetraacrylate, oligoester acrylate, and acrylates of the above compounds into methacrylate. And the like; triallyl cyanurate, triallyl trimellitate; and the like.

These cross-linking agents are based on other monomer components 10
1% by weight or less with respect to 0% by weight, preferably 0.00
It is preferably used in the range of 1 to 0.5% by weight.

Among these crosslinkable monomers, aromatic divinyl compounds (particularly divinylbenzene), aromatic groups and ether bonds are preferably used for the resin for developers from the viewpoints of fixing property and anti-offset property. Examples include chain-containing diacrylate compounds.

The toner of the present invention may contain a charge control agent.

The following substances control the toner to be negatively charged.

Organic metal complexes and chelate compounds are effective, for example, monoazo metal complexes, acetylacetone metal complexes, aromatic hydroxycarboxylic acids, and aromatic dicarboxylic acid type metal complexes. Other examples include aromatic hydroxycarboxylic acids, aromatic mono- and polycarboxylic acids and their metal salts, anhydrides, esters, and phenol derivatives such as bisphenol.

There are the following substances for controlling the toner to have a positive charge property.

Modified products of nigrosine and fatty acid metal salts. Tributylbenzylammonium-1-hydroxy-4-naphthosulfonate, quaternary ammonium salts such as tetrabutylammonium tetrafluoroborate,
And onium salts such as phosphonium salts and the like, lake pigments thereof, triphenylmethane dyes and lake pigments thereof (as the laker, phosphotungstic acid, phosphomolybdic acid, phosphotungsten molybdic acid, tannin Acid, lauric acid, gallic acid, ferricyanide, ferrocyanide, etc.) metal salt of higher fatty acid; dibutyltin oxide, dioctyltin oxide, diorganotin oxide such as dicyclohexyltin oxide; dibutyltin borate, dioctyltin borate, dicyclohexyltin borate Such as diorgano tin borate; these can be used alone or in combination of two or more kinds. Among these, charge control agents such as nigrosine and quaternary ammonium salts are particularly preferably used.

When an organic solvent is used when mixing the binder resin of the present invention and the wax, the organic solvent is xylene,
Toluene or cumene is used.

The organic solvent is removed by heating the organic solvent solution of the polymer, removing 10 to 80% by weight of the organic solvent under normal pressure, and then removing the residual solvent under reduced pressure. At this time, the organic solvent solution has a boiling point of 20% or more of the organic solvent used.
It is necessary to keep the temperature below 0 ° C. If the boiling point of the organic solvent is lower than the efficiency of solvent distillation, the polymer in the organic solvent is subjected to unnecessary shearing force, redispersion of each constituent polymer is promoted, and in a micro state. Cause phase separation.
Further, when the temperature exceeds 200 ° C., depolymerization of the polymer proceeds, and not only oligomer formation by molecular cleavage but mixing of residual monomer into the product resin due to monomer formation leads to unsuitable toner binder for electrophotography. Becomes

The final form of the resin composition of the present invention is:
The coarsely pulverized particles are more efficient when mixed with other toner materials. The particle size is preferably 0.2 mm or less, and more preferably 0.1 mm or less before use.

The wax used in the present invention is a low molecular weight alkylene polymer obtained by radical polymerization of alkylene under a high pressure or a Ziegler catalyst under a low pressure, an alkylene polymer obtained by thermally decomposing a high molecular weight alkylene polymer, and monoxide. An antioxidant may be added by using a wax such as a synthetic hydrocarbon obtained by hydrogenating a hydrocarbon distillation residue obtained by an Arge process from a synthetic gas consisting of carbon and hydrogen.
Further, those obtained by fractionating the hydrocarbon wax by the use of press sweating method, solvent method, vacuum distillation or fractional crystallization method are preferably used. The hydrocarbon as a matrix is one synthesized by a reaction of carbon monoxide and hydrogen using a metal oxide catalyst (often two or more multi-component system), for example, gintol method, hydrocoal method (fluidized catalyst bed). Or a hydrocarbon with up to several hundred carbon atoms obtained by the Arge process (using a fixed catalyst bed) that produces a large amount of waxy hydrocarbons, or a hydrocarbon obtained by polymerizing alkylene such as ethylene with a Ziegler catalyst. It is preferable because it is a linear hydrocarbon having a small number of branches, a small branch, and a long saturation. A wax synthesized by a method that does not rely on the polymerization of alkylene is particularly preferable because of its molecular weight distribution. Also, a hydroxyl group, a carboxyl group, an amino group, an ester group,
It may have a functional group such as an amide group.

In the molecular weight distribution, the molecular weight is 400 to 1
It is preferable that the peak exists in the region of 5,000, preferably in the region of 450 to 7,000, and particularly preferably in the region of 500 to 4000. By having such a molecular weight distribution, it is possible to give the toner favorable thermal characteristics.

As other physical properties, the density at 25 ° C. is 0.92 (g / cm ³ ) or more and the penetration is 5.0 (10 ^−1).
mm) or less, preferably 4.0 (10 ^-1 mm) or less. If it deviates from these ranges, it tends to change at low temperatures and the storage stability and developability tend to deteriorate. 140 ° C again
Has a melt viscosity of 500 cP or less, preferably 25
It is 0 cP or less, particularly preferably 100 cP or less. 5
When it exceeds 00 cP, the plasticity and the releasability are deteriorated, and the excellent fixability and offset resistance are affected. The softening point is preferably 140 ° C. or lower (more preferably 120 ° C. or lower). 140 ° C
If it exceeds, the temperature at which the releasability works particularly effectively becomes high,
The excellent offset resistance is affected.

The content of the wax is 20 parts by weight or less with respect to 100 parts by weight of the binder resin, and it is effective to use 0.5 to 10 parts by weight. Even when used in combination with other waxes. I do not care.

Specific examples of waxes applicable to the present invention include polypropylene, polyethylene, microcrystalline wax, carnauba wax, sazol wax, paraffin wax and the like, and oxides and graft modified products thereof.

In the present invention, the molecular weight distributions of the resin and wax are measured by GPC (gel permeation chromatography) under the following conditions.

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

<GPC Measurement Conditions for Wax> Apparatus: GPC-150C (manufactured by Waters) Column: GMH-HT (manufactured by Tosoh Corporation) Dual temperature: 135 ° C. Solvent: o-dichlorobenzene (addition of 0.1% ionol) ) Flow rate: 1.0 ml / min. Sample: Inject 0.4 ml of a sample with a concentration of 0.15% by weight

The molecular weight calibration curve prepared from the monodisperse polystyrene standard sample is used for the measurement of the molecular weight of the sample measured under the above conditions. Furthermore, the molecular weight of the wax is calculated by converting it with a conversion formula derived from the Mark-Houwink viscosity formula.

In the toner of the present invention, the charging stability,
In order to improve developability, fluidity and durability, it is preferable to add an inorganic fine powder.

The inorganic fine powder used in the present invention includes:
Examples thereof include fine silica powder, titanium oxide, and alumina. Specific surface area by nitrogen adsorption measured by BET method Among these is 30 m ² / g or more (especially 50 to 400 m ² /
Those in the range of g) give good results. Toner 10
It is preferable to use 0.01 to 8 parts by weight, preferably 0.1 to 5 parts by weight, of inorganic fine powder with respect to 0 part by weight.

The inorganic fine powder used in the present invention is
Silicone varnishes, various modified silicone varnishes, silicone oils, various modified silicone oils, silane coupling agents, silane coupling agents having a functional group, and other organosilicon compounds for the purpose of hydrophobizing, controlling electrostatic properties, etc. It is also preferable that the treatment is carried out with a treating agent such as the above, or in combination with various treating agents.

As other additives, lubricants such as Teflon, zinc stearate, polyvinylidene fluoride, and polyvinylidene fluoride are preferable. Alternatively, an abrasive such as cerium oxide, silicon carbide, or strontium titanate,
Of these, strontium titanate is preferable. Alternatively, for example, a fluidity-imparting agent such as titanium oxide or aluminum oxide, among which a hydrophobic agent is particularly preferable. Anti-caking agent,
Alternatively, for example, a conductivity-imparting agent such as carbon black, zinc oxide, antimony oxide, or tin oxide, or white particles and black particles having opposite polarities can be used in a small amount as a developing property improver.

Further, when the toner of the present invention is used as a two-component type developer, it is used as a mixture with carrier powder.
In this case, the mixing ratio of the toner and the carrier powder is 0.1 to 50% by weight, preferably 0.5 to 1 as the toner concentration.
0% by weight, more preferably 3 to 5% by weight is desirable.

As the carrier that can be used in the present invention, all known carriers can be used. For example, magnetic powder such as iron powder, ferrite powder, nickel powder, glass beads, etc. Examples include those treated with a resin, a vinyl resin, a silicone resin, or the like.

Further, the toner of the present invention may further contain a magnetic material to be used as a magnetic toner. In this case, the magnetic material also serves as a coloring agent. Examples of the magnetic material contained in the magnetic toner of the present invention include iron oxides such as magnetite, hematite, and ferrite; metals such as iron, cobalt, and nickel; or aluminum, cobalt, copper, lead, magnesium, and tin of these metals. Zinc, antimony,
Examples thereof include alloys of metals such as beryllium, bismuth, cadmium, calcium, manganese, selenium, titanium, tungsten and vanadium, and mixtures thereof.

These magnetic materials have an average particle size of 0.1 to 2 μm.
m, preferably about 0.1 to 0.5 μm, and the amount contained in the toner is about 20 to 200 parts by weight with respect to 100 parts by weight of the resin component, and particularly preferably 40 per 100 parts by weight of the resin component. ~ 150 parts by weight is good.

Further, the magnetic characteristics under application of 10 K oersted are coercive force of 20 to 150 oersted and saturation magnetization of 50 to 50 oersted.
It is preferably 200 emu / g and a residual magnetization of 2 to 20 emu / g.

The colorant that can be used in the toner of the present invention includes any appropriate pigment or dye. Toner colorants are well known, and examples of pigments include carbon black, aniline black, acetylene black, naphthol yellow, hansa yellow, rhodamine lake, alizarin lake, red iron oxide, phthalocyanine blue, and indanthrene blue. These are used in an amount necessary and sufficient for maintaining the optical density of the fixed image.
0.1 to 20 parts by weight, preferably 2 to 10 parts by weight
Good addition of parts by weight. Further, a dye is further used for the same purpose. For example, azo dye, anthraquinone dye,
There are xanthene dyes, methine dyes, etc., and 0.1 to 20 parts by weight, preferably 0.3 to 100 parts by weight of the resin.
A good amount is 3 parts by weight.

To prepare a toner for developing an electrostatic image using the resin composition for toner of the present invention, the resin composition for toner of the present invention, a pigment as a coloring agent, or a dye, a magnetic material,
If necessary, a charge control agent, other additives, etc. are thoroughly mixed by a mixer such as a Henschel mixer or a ball mill, and then melted, kneaded and kneaded by using a heat kneader such as a heating roll, kneader or extruder. The toner according to the present invention can be obtained by slicing and dispersing or dissolving a metal compound, a pigment, a dye, and a magnetic material in a binder resin, cooling and solidifying, and then pulverizing and classifying.

Further, if desired, desired additives may be sufficiently mixed with a mixer such as a Henschel mixer to obtain the toner for developing an electrostatic image according to the present invention.

In the present invention, it is possible to use a general kneading method in the kneading step after the pre-mixing, but in particular, the performance of the binder resin according to the present invention is not impaired and the other kneading methods described above can be used. In order to obtain good dispersibility and wettability with the additive, the extruder method using an extruder having a uniaxial or biaxial screw is preferable. In this case, the extruder kneading shaft length (L)
And the ratio (L / D) of the diameter to the diameter (D) is 10 to 60, and the mixture is melt-kneaded. This is to effectively reduce the melt viscosity of the binder resin during melt-kneading and to prevent the resin from being subjected to excessive shearing force to disperse the toner constituents, thereby reaggregating the binder constituents and the molecular chain. In particular, it is possible to prevent the molecular chain of the polymer component from being broken. When the L / D is less than 10 and kneaded, the melt viscosity of the binder resin is not sufficiently lowered, so that the wettability with the additive constituting the toner is not sufficiently obtained and a good dispersion state cannot be achieved. In addition, the shearing force may act strongly on the binder resin, and the polymer chain may be broken. Also, L / D is 6
If it is greater than 0, the melt viscosity of the binder resin may be unnecessarily lowered, resulting in poor dispersion of other additives and phase separation of the polymer component of the binder. These tendencies become more remarkable when, for example, a magnetic toner containing an additive having a large specific gravity difference with the binder resin such as a magnetic material is produced, and the L / D is limited to 15 to 55. It is more preferably 23 to 35.

As described above, by specifying the conditions during kneading, it becomes possible to keep the change in the molecular weight of the toner resin composition during toner production to a necessary minimum.

Also, the shaft in the extruder kneader,
As the paddle structure, at least one kneading portion having an effect of retaining the kneaded material is preferable, and more preferably 2 or more kneading portions.
There should be more than one place.

From the viewpoint of achieving high image quality, the toner particle size preferably has the following particle size distribution.

That is, the amount of toner having a particle size of 12.7 μm or more is preferably 2.0% by weight or less, more preferably 1.0% by weight or less, and further preferably 0.5% by weight or less. If it is more than 2.0% by weight, it will hinder the reproduction of fine lines. The toner of the present invention has a weight average diameter of 4 to 8
It is preferably μm. When the weight average diameter exceeds 8 μm, the resolution is not good, and conversely, when it is less than 4 μm, fog, transferability and the like deteriorate.

The particle size distribution of the toner can be measured by various methods, but in the present invention, it was measured using a Coulter counter.

That is, a Coulter counter TA-II type (manufactured by Coulter) is used as a measuring device, and an interface (manufactured by Nikkaki) for outputting number average distribution and volume distribution and a CX-1 personal computer (manufactured by Canon) are connected. Then, the electrolyte is 1
% NaCl aqueous solution is prepared. As a measuring method, a surfactant as a dispersant, preferably 0.1 to 5 ml of an aqueous solution of alkylbenzene sulfonate is added to 100 to 150 ml of the electrolytic aqueous solution, and 2 to 20 mg of a measurement sample is further added.
(The number of particles is about 30,000 to about 300,000). The electrolytic solution in which the sample is suspended is subjected to a dispersion treatment with an ultrasonic disperser for about 1 to 3 minutes, and is subjected to a Coulter Counter TA-II type,
Using a 100 μm aperture as an aperture, the particle size distribution of particles of 2 to 40 μm was measured based on the number, and the value according to the present invention was determined therefrom.

[0105]

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

Production Example 1 of Resin Composition (Synthesis of Low Molecular Weight Polymer) Xylene 300 was placed in a polymerization kettle.
After adding a part by weight and thoroughly replacing the inside of the container with nitrogen while stirring, the temperature is raised to reflux.

Under this reflux, a mixed solution of 83 parts by weight of styrene, 17 parts by weight of -n-butyl acrylate, and 2 parts by weight of di-tert-butyl peroxide was added dropwise over 4 hours, and then the mixture was held for 2 hours. Polymerization was completed to obtain a low molecular weight polymer solution.

A portion of this polymer solution was sampled,
GPC and glass transition point (Tg) of the obtained low molecular weight polymer were measured by drying under reduced pressure, and weight average molecular weight (Mw) = 11,200, number average molecular weight (M
n) = 8,400, peak molecular weight (Mp) = 10,000
0, Tg = 60 ° C.

(Synthesis of High Molecular Weight Polymer) 250 parts by weight of degassed water and 50 parts by weight of a 1% by weight aqueous solution of polyvinyl alcohol were put into a polymerization kettle, and then 83 parts by weight of styrene and 17 parts by weight of n-butyl acrylate. Part, divinylbenzene 0.
001 parts by weight and 2,2-bis (4,4-di-tert)
-Butylperoxycyclohexyl) propane 0.1 part by weight was added and the mixture was stirred to give a suspension.

After the inside of the polymerization kettle was placed under a nitrogen atmosphere, the temperature was 85 ° C.
The temperature was raised to and polymerization was started. After maintaining at the same temperature for 20 hours, 0.1 part by weight of benzoyl peroxide was additionally added, and further maintaining for 8 hours to complete the polymerization.

Next, the polymer particles were filtered out, washed thoroughly with water, and dried. GPC and Tg of this high molecular polymer
Was measured, Mw = 1050,000, Mn
= 95,000, Mp = 650,000, Tg = 61 ° C
Met.

30 parts by weight of the high molecular weight polymer having the above physical properties was dissolved in 100 parts by weight of xylene.

Here, the peak molecular weight is 5000 and the softening point is 12
5 parts by weight of 9 ° C. low-molecular-weight polypropylene was added to 100 parts by weight of the resin, and the mixture was heated, stirred, dissolved and mixed for 10 hours under reflux.

Next, 135 parts by weight of this mixed solution and 290 parts by weight of the low molecular weight polymer solution were mixed under reflux.

After that, the organic solvent was distilled off, and the obtained resin composition was drawn, formed into a plate having a thickness of 1 mm, and cooled.

This resin composition was prepared by mixing a low molecular weight component and a high molecular weight component in a ratio of 70:30 and further adding a resin 100
5 parts by weight of wax are dispersed with respect to parts by weight.

Further, thin sections of the resin were sampled before and after the stretching of the resin composition with a pressure roller and observed with a video microscope (Wilson Co.) and an electron microscope and a transmission electron microscope. The shape of the wax domain before molding was almost spherical. However, the domain particle size was broad (maximum diameter of about 50 μm, mode diameter of 18 μm). The domain shape of the wax after stretch molding was rod-like, the minor axis was uniform, and the average diameter was about 4.5 μm.

[Production Example 2 of Resin Composition] The low molecular weight polymer and the high molecular weight polymer of Production Example 1 of the resin composition were mixed with resin solids of 7%.
The mixture was mixed in a low molecular weight polymer solution so that the ratio became 0:30.

Thereafter, a wax was mixed therein as in Production Example 1, desolvated, stretched and molded, and cooled to obtain a resin composition.
The average diameter of the minor axis of the wax in this resin is about 11
was μm.

[Production Example 3 of resin composition] A production example in which the ratio of the low molecular weight component to the high molecular weight component of the resin in Production Example 1 of the resin composition was set to 50:50, and the amount of wax was 7 parts by weight. A resin composition was obtained in the same manner as in 1. The molding conditions were changed and the sheet was stretched to a plate shape of 0.5 mm.

[0121] Further, when the resin flakes were sampled and observed before and after the stretch forming of this resin composition, the domain shape of the wax before the stretch forming was almost spherical. However, the domain particle size distribution was broad (maximum diameter 100 μm, mode diameter 25 μm
m). The domain shape of the wax after stretch molding was rod-like, the minor axis was uniform, and the average diameter was about 4 μm.

[Production Examples 4 and 5 of Resin Composition] The waxes in Production Example 1 of resin composition were changed to the waxes shown in Table 1, and Resin Compositions 4 and 5 were obtained in the same manner as in Production Example 1.

[Comparative Production Example 1 of Resin Composition] The domain shape deforming step of the resin composition in Production Example 3 of resin composition was omitted.

[Production Example 6 of resin composition] Styrene-n-butyl acrylate copolymer GPC molecular weight Peak molecular weight 40,000 Tg 61 ° C A resin having the above physical properties was prepared by solution polymerization. 5 parts by weight of low molecular weight polyethylene having a peak molecular weight of 2200 and a softening point of 115 ° C. was added to 100 parts by weight of the resin,
The temperature was raised, the mixture was stirred under reflux, and dissolved and mixed.

After that, the organic solvent of the mixed solution was distilled off, and it was taken out and stretched by a pressure roller stretching machine to form a plate having a thickness of 0.5 mm, followed by cooling to obtain a resin composition.

[Comparative Production Example 2 of Resin Composition] The domain shape deforming step of the resin composition in Production Example 4 of resin composition was omitted.

[Production Example 7 of Resin Composition] The low molecular weight polymer obtained in Production Example 1 of Resin Composition and the high molecular weight polymer having the following physical properties were produced in accordance with Production Example 1.

High molecular polymer Mw = 580,000 Mn = 55,000 Mp = 400,000 Tg = 60 ° C.

The average minor axis of the wax in the resin composition molded into a plate was 4.5 μm.

Tables 1 and 2 collectively show Production Examples 1 to 7 and Comparative Examples 1 and 2 of the above resin compositions.

[Examples 1 to 6 and 9 and Comparative Examples 1 and 2] Resin composition production example 1 100 parts by weight (coarsely pulverized product) Magnetic fine powder 100 parts by weight Negative charge control agent (azo dye-based iron complex) 2 parts by weight The above toner materials were uniformly mixed with a Henschel mixer, and then melt-kneaded with a twin-screw extruder heated to 130 ° C. Further, in the biaxial extruder, two kneading parts were provided. The L / D of the extruder at this time was 26.5.

The kneaded product was cooled, coarsely pulverized with a hammer mill, and further finely pulverized with a jet mill. The obtained pulverized product was classified by wind to obtain classified powder having a weight average diameter of 6.1 μm.
The weight% of particles having a size of 12.7 μm or more was 0%. 1.2 parts by weight of hydrophobic silica fine powder was dry mixed with 100 parts by weight of classified powder in a Henschel mixer,
The toner according to Example 1 was obtained.

Other than the above, the resin composition of Production Example 1 was replaced with those of Production Examples 2 to 6 and 9, and Comparative Production Examples 1 and 2, respectively, in the same manner as in Examples 2 to 6 and 9, toners of Comparative Examples 1 and 2 were obtained.

The following evaluations were performed on each of the toners obtained here.

That is, regarding the image forming apparatus, in this embodiment, a commercially available laser beam printer LBP-8II is used.
As shown in FIG. 1 (schematic diagram) of (Canon), an elastic blade made of urethane rubber is attached to the device unit portion (toner cartridge), and the heat fixing device is further shown in FIG. 2 (exploded perspective view) and FIG. (Fig.) Was modified and the following conditions were set.

An electrostatic latent image is formed by setting the primary charging to -600 V, a gap (300 μm) is set in a non-contact manner between the photosensitive drum 3 and the developer layer on the developer carrying member 6 (including the magnet), and an AC bias ( f = 1800 Hz Vpp = 1200 V) and a DC bias (V _DC = −400 V) are applied to the developing sleeve by the bias applying means 12, while V _L is −
The electrostatic charge image was developed at 150 V by reversal development to form a toner image on the OPC photoreceptor. The obtained toner image was transferred to plain paper at a positive transfer potential, and the plain paper having the toner image was fixed on the paper through a heat fixing device. At this time, the surface temperature of the temperature detecting element 21d of the heating body 21 of the heating fixing device is 150 ° C., the total pressure between the heating body 21 and the pressure roller 23 is 5 kg, and the nip between the pressure roller and the film is 2.
The fixing film 22 has a thickness of 5 mm, and a heat-resistant polyimide film having a thickness of 50 μm and a release layer having a low resistance in which a conductive substance is dispersed in PTEF is provided on the contact surface with the transfer material.

Under the above set conditions, normal temperature and normal humidity (25 ° C., 6
Under an environment of 5% RH, a printout test was conducted on 3000 sheets continuously at a printing speed of 4 sheets (A4) / min, and the obtained images were evaluated for the following items.

The evaluation results are shown in Table 3.

1) Fixability Using the external fixing device of the fixing device shown in FIGS.
After sec, the unfixed image (toner amount on the image is 0.6 m
g / cm ² ) and the image density is measured using a Macbeth reflection densitometer (manufactured by Macbeth).

The fixing property is such that a load of 50 g / cm ² is applied,
The fixed image was rubbed with a soft thin paper, and the reduction rate (%) of the image density before and after the rubbing was evaluated.

⊚: 5% or less O: 5 to 10% Δ: 10 to 20% ×: 20% or more

For Example 3 and Comparative Example 1, the set temperature was 160 ° C.

2) Anti-Offset Property The anti-offset property was evaluated by printing out a sample image having an image area ratio of about 5% and measuring the degree of stain on the image after 3000 sheets.

⊚: Very good (not generated) ○: Good (almost no occurrence) Δ: Practical (generally generated) ×: Not practical

3) Blocking resistance As for the blocking resistance, the toner was left in a constant temperature bath of 53 ° C. for 7 days, and its cohesiveness was visually evaluated.

⊚: Very good (no difference observed before leaving) ○: Good (slightly less fluidity than before leaving but not significantly different) Δ: Practical (slightly less fluid than before leaving (No effect on image quality) ×: Not practical (blocking)

4) High image quality dot reproducibility Dot reproducibility was evaluated by a microscope after an image formation test using a checker pattern of 80 × 50 μm shown in FIG.
Sharpness of toner image, toner splash to non-image area,
The presence or absence of a defect in the black portion was evaluated.

⊚: 2 or less defects / 100 defects ○: 3 to 5 defects / 100 defects Δ: 6 to 10 defects / 100 defects ×: 11 defects or more / 100 defects

Regarding the dot reproducibility, the initial durability test and 3
Evaluations were made after 000 sheets were run.

[Embodiment 7] In Embodiment 4, L / D is set to 14.7.
A toner was obtained in the same manner except that the toner was melted and kneaded with a shaft extruder.

Table 3 shows the results of the same evaluations as in Examples 1-6 and Comparative Examples 1-2.

[Embodiment 8] L / D of Embodiment 4 is 55.5.
A toner was obtained in the same manner except that the toner was melted and kneaded with a shaft extruder.

Table 3 shows the results of the same evaluations as in Examples 1-6 and Comparative Examples 1-2.

[0154]

[Table 1]

[0155]

[Table 2]

[0156]

[Table 3]

[0157]

According to the present invention, in a toner resin composition containing at least a binder resin and wax, the wax domain shape in the toner resin composition is dispersed in a rod shape or a needle shape (linear shape). As a result, the dispersibility of the wax in the toner is remarkably improved, and as a result, high image quality can be achieved while satisfying the high fixing property and anti-offset property.

[Brief description of drawings]

FIG. 1 is a schematic explanatory diagram of an image forming apparatus used in an embodiment of the present invention.

FIG. 2 is an exploded perspective view of a main part of a fixing device used in an embodiment of the present invention.

FIG. 3 is an enlarged cross-sectional view of a main part showing a film state of the fixing device used in the embodiment of the present invention when the fixing device is not driven.

FIG. 4 is an explanatory diagram of a checkered pattern for checking the developing characteristics of toner.

FIG. 5 is a schematic diagram of an observation example of a dispersed state of wax in the resin composition of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Developing device 2 Developer container 3 Latent image carrier 4 Transfer means 5 Laser light or analog light 6 Developing sleeve 7 Heating / pressurizing fixing means 8 Cleaning blade 9 Elastic blade 11 Charger 12 Bias applying means 13 Magnetic developer 14 Cleaning means 15 magnetic field generating means 19 erase exposure 20 stay 21 heating body 21a heater substrate 21b heating element 21c surface protection layer 21d temperature measuring element 22 fixing film 23 pressure roller 24 coil spring 25 film end regulating flange 26 power supply connector 27 power disconnecting member 28 inlet Guide 29 Exit guide (separation guide) 51 Resin 52 Wax

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Shunji Suzuki 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Akihiko Nakazawa 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Within the corporation

Claims (2)

[Claims] 1. A developer for electrostatic charge image development obtained by kneading and pulverizing at least a colorant and a resin composition for toner obtained by melting or dissolving and mixing at least a binder resin and a wax. A developer for developing an electrostatic charge image, wherein the domain shape of the wax in the resin composition is dispersed in a rod shape or a needle shape (linear shape). 2. A method for producing a resin composition for a toner containing at least a binder resin and a wax, wherein at least the binder resin and the wax are melted or dissolved and mixed, and then the domain shape of the wax is changed from spherical to rod-like (needle-like). A method for producing a resin composition for a toner, comprising a step of deforming the resin composition into a linear shape.