JP3230040B2 - Toner for developing electrostatic images - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to electrophotography, electrostatic printing,
The present invention relates to a toner for visualizing an electrostatic latent image in an image forming method such as magnetic 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.
Many methods are known as described in Japanese Patent Application Laid-Open Publication No. Sho. 43-24748, and the like. Generally, a photoconductive substance is used to form an electric latent image on a photoreceptor by various means. The latent image is developed with toner to form a visible image, and the toner image is transferred to a transfer material such as paper as necessary, and then the toner image is fixed on the transfer material by heat and pressure. To obtain a copy, and the remaining toner that has not been transferred onto the photoreceptor is cleaned by various methods, and the above-described steps are repeated.

In recent years, devices using electrophotography have begun to be used not only for simply copying original documents, but also for copying high-resolution images such as digital printers or graphic designs as computer outputs.

As for printer devices, LED and LBP printers have become the mainstream in the recent market, and the direction of technology has been increased to higher resolution, that is, from 240, 300 dpi to 400, 600, 800 dpi. There is a demand for the development of devices with higher image quality and higher definition.

[0005] In addition, as the networking of computers inside and outside the office progresses, the amount of power required to operate the computers and computer peripherals is increasing.
It is desired to develop a device with low power consumption that solves this.

For this reason, higher reliability has been strictly pursued, and the required performance has become higher. Accordingly, it has been impossible to achieve improvements in the performance of an image forming method including toner and a method of reducing power consumption. Better machines are no longer feasible.

The most important performance required for toner in digital printers and copying of high-definition images is fixing performance.

In order to improve the fixing performance of the toner,
Generally, the thermal properties of the binder, the thermal properties of the wax, and the like are improved to control the melt viscoelasticity of the toner to increase the viscosity.

On the other hand, various methods and apparatuses have been developed for the fixing step, but the most common method at present is a pressure heating method using a heat roller.

In the pressure heating method using a heating roller, fixing is performed by allowing the toner image surface of the sheet to be fixed to pass through the surface of a heat roller having a surface formed of a material having a releasing property with respect to the toner, while contacting the surface under pressure. It is what you do. In this method, since the surface of the heat roller and the toner image of the sheet to be fixed come into contact with each other under pressure, the thermal efficiency at the time of fusing the toner image onto the sheet to be fixed is extremely good, and the fixing can be performed quickly. And is very effective in high speed electrophotographic copiers. However, in the above method, since the surface of the heat roller and the toner image come into contact with each other under pressure in a molten state, a part of the toner image adheres to and transfers to the surface of the fixing roller, thereby fouling the next sheet to be fixed ( Offset phenomenon). Preventing toner from adhering to the surface of the heat fixing roller is one of the essential conditions of the heat roller fixing method.

In recent years, a fixing device has been put into practical use, which comprises a pressing member which is opposed to a heating roller and is in pressure contact with a heating member, and in which a recording material is brought into close contact with the heating member via a film, instead of a heat roller. However, since the toner surface is melted, the offset phenomenon is more likely to occur, and it is necessary to prevent the offset phenomenon.

On the other hand, in the latent image portion of the fine image, the lines of electric force are concentrated at the boundary between the exposed portion and the non-exposed portion, and the surface potential of the photosensitive member apparently increases. In particular, in a digital printer, since the latent image is constituted by ON-OFF binary basic pixels, the concentration of lines of electric force at the boundary between the exposed portion and the non-exposed portion is large. The toner amount per unit area developed into the constituted line latent image is larger than the toner amount on a normal analog image. Therefore, in the fixing of such an image, at present, there is a demand for a toner having better fixing property and offset resistance.

In addition, the printer is required to have a copy amount three to five times that of a copier of the same level, and is also required to have high durability in development and high image stability.

As described above, in recent years, the performance required for a printer has become more sophisticated, and improvements in toner fixing property, offset resistance, high image quality stability, and the like have become indispensable. ing.

Many studies have been made to improve toner performance.

For example, as disclosed in JP-A-56-16144, a method has been proposed in which a binder resin having two peaks in molecular weight distribution is used as a binder resin for a toner. However, by merely using a binder resin having two peaks, although some improvement in fixability and anti-offset property can be seen, not only does the binder resin component in the toner cause non-uniformity, but also other And disperse the toner constituent materials.

Thus, for example, the compatibility of the toner constituent materials,
In order to improve the dispersibility, when the kneading conditions at the time of melt kneading during the production of the toner are strengthened, the molecular weight at the time of the toner decreases due to the molecular chain breakage of the binder resin in the toner due to the kneading, so that the offset resistance is improved. Are worsened.

Further, JP-A-2-168264, JP-A-2-23569, JP-A-5-173363,
In JP-A-5-173366 and JP-A-5-241371, the molecular weight, the mixing ratio, the acid value and the ratio of the low molecular weight component and the high molecular weight component in the binder resin are controlled, and the fixing property, the offset resistance and the image quality are controlled. Toner binder compositions and toners having improved properties, blocking resistance, and charging start-up properties have been proposed, but are still low in perfection.

In particular, in the adjustment of the acid value disclosed in the above publication, poor dispersion of a coloring agent such as magnetic iron oxide, a charge control agent, and other additives occurs, and fog due to contamination of the surface of the developing carrier such as a carrier or a sleeve is caused. And image deterioration such as a decrease in density.

In order to solve these problems, it is necessary for the toner design to select a material having good compatibility and physical miscibility with each of the toner constituting materials, but it is still insufficient.

On the other hand, for the purpose of preventing the toner from adhering to the surface of the fixing roller, for example, the roller surface is formed of a material having excellent releasability to the toner, such as silicone rubber or a fluororesin, and the surface thereof is further prevented from being offset. Further, in order to prevent the roller surface from being fatigued, the roller surface is coated with a thin film of a liquid having good releasability such as silicone oil. However, this method is extremely effective in preventing toner offset, but has a problem that a fixing device is complicated because a device for supplying an anti-offset liquid is required. . Therefore, it is not preferable that the offset is prevented by supplying the offset preventing liquid, and the development of an offset-resistant toner having a wide fixing temperature range is desired.

Therefore, in order to increase the releasability of the toner, a method of adding a wax such as low molecular weight polyethylene or polypropylene which sufficiently melts when heated is used.

Also, JP-A-52-3304, JP-A-52-3305, JP-A-57-52574, JP-A-61-138259, and JP-A-56-8
JP-A No. 7051, JP-A-63-188158, JP-A-63-113558, and the like disclose techniques containing a wax in a toner.

However, these waxes increase the releasability of the toner, make it difficult for the toner to adhere to the surface of the fixing roller, and improve the offset resistance. However, these waxes are difficult to be uniformly dispersed in the toner and are free or unevenly distributed. The used wax tends to have an adverse effect on developability and the like after repeated use. Further, there is a concern that the elasticity of the toner is reduced due to the plasticizing effect of the wax, the toner strength is reduced, and the photoreceptor and each of the developing members are contaminated with the toner. Notably, there is still room for improvement.

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

[0026]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to significantly improve the disadvantages of the prior art, realize high-quality images, exhibit high developability, and exhibit high image quality stability. Another object of the present invention is to provide a toner for developing an electrostatic charge image which is highly adaptable to an electrophotographic process which does not adversely affect a photosensitive member or a developer carrier.

It is a further object of the present invention to provide a toner for developing electrostatic images which exhibits high performance in terms of fixability and offset resistance.

It is a further object of the present invention to provide a toner for developing an electrostatic image, which exhibits high storage stability.

It is a further object of the present invention to provide a toner for developing an electrostatic charge image which does not cause charging unevenness even when a large number of images are formed in an image forming method having a contact charging step.

It is a further object of the present invention to use a developing method for charging an electrostatic latent image carrier using a contact charging member without contaminating the contact charging member and thus increasing the surface resistance without increasing the surface resistance. An object of the present invention is to provide a toner for developing an electrostatic image without causing defects.

[0031]

Means and Action for Solving the Problems The present inventors have
The following inventions have been achieved in the course of intensive research to solve the various problems described above and to develop a toner for developing an electrostatic image that meets the object of the present invention.

That is, the present invention relates to a toner having at least a binder resin, a low molecular weight wax and a colorant, wherein the binder resin has a low molecular weight component and a high molecular weight component, and is used for GPC (gel permeation chromatography). The GPC chart of the binder resin has at least two maximum values in the chart, and the GPC chart of the binder resin is divided into four sections of A, B, C and D from the smaller molecular weight using the maximum value and the minimum value as division points. When the acid values of the components are a, b, c and d,
The present invention relates to a toner for developing an electrostatic image, which satisfies the following conditions.

B <a <d <c (Equation 1)

The present inventors consider the reason why the toner according to the present invention exerts the effects of the present invention as follows.

By controlling the state and total amount of the acid contained in the binder resin according to the present invention, the π-electron conjugate system of the binder resin derived from the styrene species is activated, and the chargeability of the binder resin is improved. Guess is improving. This is considered to contribute to the improvement of the developability.

Further, by controlling the state and the total amount of the acid contained in the binder resin, the interaction between the binder resin and the low molecular weight wax is appropriately regulated, and the low molecular weight wax is It is presumed that the resin plays a role of sufficiently extracting the performance without impairing the performance of the resin. It is considered that this has the effect of simultaneously improving low-temperature fixability, offset resistance and storage stability while maintaining high developability.

Further, by controlling the state and the total amount of the acid contained in the binder resin, not only can the compatibility with the low molecular weight wax be improved, but also other toner raw materials,
For example, it is presumed that they play a role of increasing the dispersion of a magnetic substance, a charge control agent, and the like in a binder resin. This prevents the charge control agent and the low molecular weight wax from agglomerating during the production of the toner, suppresses the non-uniform charging state between the toner particles, suppresses the occurrence of selective development, and further reduces the charge control agent in the toner particles. Preventing agglomeration / uneven distribution is useful for showing a high developing property and eliminating a decrease in the strength of the toner particles.

Further, by combining the binder resin according to the present invention with the low molecular weight wax, the toner elasticity derived from the binder resin is appropriately maintained and the releasability of the toner surface derived from the low molecular weight wax is improved. It is estimated to fulfill.
This is considered to contribute to the fact that uneven charging does not occur when a large number of images are output, and no contamination occurs to the contact charging member and the like.

Further, the toner containing the low-molecular weight wax according to the present invention has good fixing properties as well as offset resistance due to the plasticizing effect of the low-molecular weight wax. The reason for this effect is considered as follows. Since the terminal functional group of the low molecular weight wax has polarity, it interacts with the functional group in the toner binder resin, so that the low molecular weight wax can stay on the toner surface for a relatively long time near the fixing temperature. It is presumed that the anti-offset property is improved because the releasability of the toner is improved. Further, it is considered that the toner containing the low-molecular-weight wax has improved fixability because the low-molecular-weight wax has a low molecular weight.

Further, the present invention will be described in detail.

In a toner having at least a binder resin, a low molecular weight wax and a colorant, the binder resin has a low molecular weight component and a high molecular weight component, and has at least two maxima in a GPC (gel permeation chromatograph) chart. The GPC chart of the binder resin has a maximum value and a minimum value as dividing points.
It is necessary to satisfy the following conditions when dividing into four sections of B, C and D and the acid values of the components in each section are a, b, c and d.

B <a <d <c (Equation 1)

In the above formula, since improving the dispersion of the wax in the portion A contributes to the improvement of the fixability, a is an acid value mainly related to the fixability. Further, since the optimal amount of the wax dispersed in the B and C portions contributes to the blending property of the low molecular weight polymer and the high molecular weight polymer of the binder resin, b and c are mainly used for the binder resin. Is an acid value related to the blendability of the low molecular weight polymer and the high molecular weight polymer. Further, since improving the dispersion of the wax in the portion D contributes to the improvement of the developing property and the anti-offset property, d is an acid value related to the developing property and the anti-offset property.

It is preferable that the binder resin of the present invention satisfies the following conditions.

0.05 ≦ a + b ≦ 2 (Equation 2) 5 ≦ c + d ≦ 15

In the above formula, since the dispersion of the toner constituent material depends on the amount of the acid and wax contained in the binder resin, etc., if the amount of the acid contained in A + B or C + D and the amount of the wax are not balanced, the toner constituent material is not balanced. A + b or c + d is an acid value for controlling the performance balance, because the dispersion of the particles becomes insufficient and the balance of performance such as fixability, anti-offset property and developability cannot be maintained.

If the acid value contained in each part of the binder resin does not satisfy the above formula, the following adverse effects occur.

If a + b is less than 0.05, the wax dispersibility in the low molecular weight polymer becomes poor, so that the fixability deteriorates. On the other hand, when a + b is larger than 2, the interaction between the low molecular weight component and the wax becomes larger than the interaction between the high molecular weight component and the wax, so that the chargeability of the resin becomes unstable and the developability deteriorates.

In the case of a <b, the solution viscosity increases during the production of the low-molecular-weight component, the blending property between the low-molecular-weight component and the high-molecular-weight component becomes insufficient, and the developability and the like deteriorate.

When c + d is less than 5, the chargeability of the resin becomes insufficient, and the developability deteriorates. On the other hand, when it is larger than 15, the fixability deteriorates. This is because the interaction between the high molecular weight component and the wax is greater than the interaction between the low molecular weight component and the wax, so that the wax is trapped in the high molecular weight component matrix, making it difficult for the low molecular weight component matrix to migrate to the low molecular weight component. It is considered that the plasticization effect derived from the material is not sufficiently exhibited, and the fixing property is deteriorated.

In the case of c <d, the high molecular weight polymer is gelled, and the gel component remarkably increases the elasticity of the binder resin.

When d <a, the charging property becomes unstable,
Developability deteriorates.

As described above, when the amount and the state of the acid change, the balance between the low molecular weight component, the high molecular weight component and the interaction with the low molecular weight wax is lost, and the developing property, the anti-offset property, the fixing property, etc. Performance cannot be obtained sufficiently. In addition, the dispersion of the toner constituent materials becomes insufficient, which causes image defects such as fog and scattering.

Therefore, in the present invention, it is preferable to satisfy the above expression.

Further, in the present invention, 0.06 or more and 1
It is preferable to use a vinyl binder resin having an acid value of 4 or less (more preferably 0.5 or more and 8 or less, and still more preferably 1 or more and 4 or less), and a combination of the charge control agent of the present invention and a low molecular weight wax. In this case, the dispersion of the charge control agent and the low-molecular-weight wax becomes good through the mediation of the acid component in the binder resin, and it is possible to obtain a toner that satisfies low-temperature fixability and developability at the same time and satisfies environmental stability. It becomes possible.

If the acid value of the binder resin is less than 0.06, the mediating effect of the acid component in the binder resin is reduced, so that the charge control agent and the low molecular weight wax cannot be sufficiently dispersed.
It causes fogging and scattering. On the other hand, if it exceeds 14, the amount of moisture absorbed by the acid component in the toner increases, so that charging of the toner under high temperature and high humidity becomes unstable and a sufficient image density cannot be obtained.

Further, the peak molecular weights of the two maximum values and one minimum value in the GPC chart of the binder resin are respectively represented by P
It is preferred that ₁ , P ₂ and P ₃ satisfy the following conditions.

3000 ≦ P ₁ ≦ 20,000 300,000 ≦ P ₂ ≦ 1.3 million 40,000 ≦ P ₃ ≦ 150,000 (formula 3)

If the above conditions are not satisfied, the balance between the fixing characteristics and the developing characteristics is deteriorated, which results in poor fixing, poor anti-offset properties, and fog and scattering.

Examples of the type of the binder resin used in the present invention include a homopolymer of styrene such as polystyrene and polyvinyltoluene and a substituted product thereof; a styrene-propylene copolymer, a styrene-vinyltoluene copolymer, and a styrene-
Vinyl naphthalene copolymer, styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-dimethylaminoethyl acrylate Polymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, styrene-dimethylaminoethyl methacrylate copolymer, styrene-vinyl methyl ether copolymer Polymer, styrene-vinyl ethyl ether copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-maleic acid copolymer, styrene-maleic acid ester copolymer Styrene-based copolymers such as Methyl methacrylate, polybutyl methacrylate, polyvinyl acetate, can be used alone or in combination. Among them, styrene copolymers,
In particular, a styrene-acrylic copolymer, a styrene-acrylic copolymer having a carboxyl group, and a mixture thereof are preferable in view of development characteristics, fixability, and the like.

The comonomer for the styrene monomer of the styrene copolymer used in the present invention includes, for example, acrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate, dodecyl acrylate, octyl acrylate, acrylic acid- Monocarboxylic acid having a double bond such as 2-ethylhexyl, phenyl acrylate, methacrylic acid, methyl methacrylate, ethyl methacrylate, butyl methacrylate, octyl methacrylate, acrylamide or the like; Dicarboxylic acids having a double bond such as butyl maleate, methyl maleate, dimethyl maleate and the like, and substituted products thereof; for example, vinyl esters such as vinyl chloride, vinyl acetate, and vinyl benzoate; Propylene, spot Vinyl olefins such as vinyl methyl ketone, vinyl hexyl ketone, etc .; vinyl ethers such as vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether, etc .; The monomers are used alone or in combination.

The carboxyl group-containing monomer or carboxyl group-derived monomer used in the present invention includes, for example, maleic acid, citraconic acid, dimethylmaleic acid,
Itaconic acid, alkenyl succinic acid, and anhydrides thereof; for example, unsaturated dibasic acids such as fumaric acid, methaconic acid, and dimethyl fumaric acid; and monoesters of unsaturated dibasic acids; for example, acrylic acid, methacrylic acid, crotone acid,
Cinnamic acids and anhydrides thereof; for example, α, β such as anhydrides between the above α, β-unsaturated acids and anhydrides with lower fatty acids.
-Unsaturated acids and their anhydride monomers; for example, alkenyl malonic acid, alkenyl glutanic acid, alkenyl adipic acid and anhydrides thereof, and monoesters thereof are used alone or in combination.

Among these, maleic acid, fumaric acid,
Monoesters of α, β-unsaturated dibasic acids having a structure such as succinic acid are particularly preferably used as monomers for obtaining the binder resin of the present invention.

Examples of such a monomer include monomethyl maleate, monoethyl maleate, monobutyl maleate, monooctyl maleate, monoallyl maleate, monophenyl maleate, monomethyl fumarate, monoethyl fumarate, monobutyl fumarate, Monophenyl fumarate; monobutyl n-butenylsuccinate, n
-Monomethyl octenylsuccinate, monoethyl n-butenylmalonate, monomethyl n-dodecenylglutarate,
Monobutyl n-butenyl adipate and the like can be mentioned.

As the crosslinking agent used in the present invention, a compound having two or more polymerizable double bonds is mainly used, for example, an aromatic divinyl compound such as divinylbenzene, divinylnaphthalene or the like; Carboxylic acid esters having two double bonds such as ethylene glycol diacrylate, ethylene glycol dimethacrylate, 1,3-butanediol dimethacrylate and the like;
Divinyl compounds such as divinylaniline, divinylether, divinylsulfide, divinylsulfone, and the like; and compounds having three or more vinyl groups can be used alone or as a mixture.

In the present invention, a solution polymerization method is mainly used. In the solution polymerization method, a low molecular weight polymer can be easily obtained under mild conditions by utilizing the difference in the chain transfer of radicals depending on the solvent and by adjusting the amount of the initiator and the reaction temperature, and is used in the present invention. It is preferable to obtain a low molecular weight compound in the resin composition. On the other hand, in the bulk polymerization method, a low molecular weight polymer can be obtained by polymerizing at a high temperature to increase the termination reaction rate, but there is a problem that the reaction is difficult to control.

As the solvent used in the solution polymerization, xylene, toluene, cumene, cellosolve acetate, isopropyl alcohol, benzene and the like are used. In the case of a styrene monomer mixture, xylene, toluene or cumene is preferred. These solvents are appropriately selected depending on the polymer to be polymerized.

The polymerization method of the high molecular weight component of the resin composition according to the present invention includes a solution polymerization method, an emulsion polymerization method and a suspension polymerization method.

Among these, 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 carried out using a water-soluble polymerization initiator. . In this method, the reaction heat can be easily adjusted, and the phase in which the polymerization is performed (oil phase composed of a polymer and a monomer)
And the aqueous phase are separate, so that the termination reaction rate is low, resulting in a high polymerization rate and a high degree of polymerization. Further, due to the relatively simple polymerization process and the fact that the polymerization product is fine particles, in the production of toner,
There is an advantage as a method for producing a binder resin for a toner because it is easy to mix with a colorant, a charge control agent and other additives.

However, the resulting polymer tends to be impure due to the added emulsifier, and it is necessary to perform an operation such as salting out to remove the polymer. To avoid this inconvenience, suspension polymerization is advantageous.

In the suspension polymerization, 100 parts by weight or less of the monomer (preferably 1 part by weight) is
(0 to 90 parts by weight). Examples of usable dispersants include polyvinyl alcohol, partially saponified polyvinyl alcohol, calcium phosphate, and the like. There is an appropriate amount in terms of the amount of a monomer relative to an aqueous solvent, and generally 0.05 to 1 based on 100 parts by weight of an aqueous solvent. Used in parts by weight. The polymerization temperature is suitably from 50 to 95 ° C, but should be appropriately selected depending on the initiator used and the intended polymer.

As the binder resin used in the present invention, the following polyfunctional polymerization initiators can be used.

Specific examples of the polyfunctional polymerization initiator having a polyfunctional structure 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-Di-tert-butylperoxybutane, 4,4-di-tert-butylperoxyvaleric acid-n-butyl ester, di-tert-butylperoxyhexahydroterephthalate, di-tert-butylperoxy Azelate, di-t-butylperoxytrimethyl adipate, 2,2-bis- (4,4-di-t-
Butylperoxycyclohexyl) propane, 2,2-
a polyfunctional polymerization initiator having a functional group having a polymerization initiation function such as two or more peroxide groups in one molecule such as t-butylperoxyoctane and various polymer oxides, and diallyl peroxydicarbonate; In one molecule such as butylperoxymaleic acid, t-butylperoxyallyl carbonate and t-butylperoxyisopropyl fumarate, both a functional group having a polymerization initiation function such as a peroxide group and a polymerizable unsaturated group are contained. Selected from polyfunctional polymerization initiators having

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

These initiators are used in 0.05 to 2 parts by weight per 100 parts by weight of the monomer.

In the present invention, each partial acid value of the binder resin is determined by the following method.

<Preparation of Components of Binder Resin> [Apparatus Configuration] LC-908 (manufactured by Nippon Kagaku Kogyo Co., Ltd.) JRS-86 (company; repeat injector) JAR-2 (company; autosampler) FC-201 (Gilson; fraction collector)

[Column Configuration] JAI GEL-1H-5
H (20φ × 600mm: preparative column)

[Measurement Conditions] Temperature: 40 ° C. Solvent: THF (tetrahydrofuran) Flow rate: 5 ml / min. Detector: RI Test concentration: A sample from which toner components other than the binder resin have been removed is used.

[Separation method] Separation is performed by dividing the elution time.
In the GPC chart of the sample, the molecular weight was 3000.
The maximum value among the maximal values in the GPC charts not less than 20,000 or less is P ₁ , the maximum value among the maximal values in the GPC charts having a molecular weight of 300,000 to 1.3 million or less is P ₂ , and the molecular weight is 4 If the minimum value of the minimum value in the GPC chart in more than 10,000 150,000 was P _3, to obtain each sample below. FIG. 5 shows a schematic diagram of a GPC chart of the sample.

Area from P ₁ to low molecular weight: a component Area from P ₁ to P ₃ : b component Area from P ₃ to P ₂ : c component Area from P ₂ to high molecular weight: d component

<Measurement of Acid Value of Each Separated Component> THF is distilled off from the separated sample using an evaporator. The THF is completely removed by drying under reduced pressure.

The acid value of this sample was determined according to JIS K-067.
Measure according to 0.

A 0.2-1 g sample was weighed into a 20-30 ml Erlenmeyer flask, and ethanol: toluene = 1: 2.
About 5 ml of a mixed solvent is added to dissolve the resin. If the solubility is poor, a small amount of acetone may be added. Using a phenolphthalein indicator, titration is performed with a 0.1N caustic potassium ethanol solution previously specified, and the acid value is calculated from the consumed amount of the alcoholic potassium solution by the following formula.

Acid value = KOH (ml number) × f × 56.1 /
Sample weight (where f is a factor of N / 10 KOH) In the present invention, the molecular weight distribution of the resin and the wax is measured by GPC (gel permeation chromatography) under the following conditions.

<GPC measurement conditions for resin> Apparatus: GPC-150C (manufactured by Waters) Column: KF801 to 7 (manufactured by Shodex) Temperature: 40 ° C Solvent: THF 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 condition of wax> Apparatus: GPC-150C (manufactured by Waters) Column: Duplex of GMH-HT (manufactured by Tosoh Corporation) Temperature: 135 ° C Solvent: o-dichlorobenzene (0.1% ionol added) Flow rate: 1.0 ml / min. Sample: 0.4 ml of 0.15% by weight 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. Further, the molecular weight of the wax is calculated by conversion using a conversion formula derived from the Mark-Houwink viscosity formula.

Glass transition point (Tg) of the binder resin of the present invention
Is preferably 55 ° C. or higher and 65 ° C. or lower. Tg of the binder resin
Is less than 55 ° C., the offset resistance, the storage stability and the like deteriorate. On the other hand, if it is higher than 65 ° C., the fixability deteriorates.

In the present invention, Tg was measured using a differential thermal analyzer (DSC analyzer) and DSC-7 (manufactured by PerkinElmer).

The measurement sample is 5 to 20 mg, preferably 10
Weigh the mg precisely.

This was put in an aluminum pan, and an empty aluminum pan was used as a reference.
The measurement is performed at a temperature rising rate of 10 ° C./min under normal humidity between 00 ° C.

During the heating process, an endothermic peak of the main peak in the temperature range of 40 to 100 ° C. is obtained.

The intersection of the line of the midpoint of the baseline before and after the endothermic peak appeared and the differential heat curve was defined as Tg.

The THF-insoluble content of the binder resin of the present invention is preferably 5% by weight or less. 5% by weight of THF insoluble matter
If it is contained in excess of, not only will the fixability deteriorate,
There is a problem in matching with the charging member and the cleaning member.

The THF-insoluble content of the binder resin of the present invention indicates the polymerization ratio of the polymer component (substantially cross-linked polymer) insoluble in the THF solvent in the resin composition in the toner. Can be used as a parameter indicating the degree of crosslinking of the resin component containing The THF-insoluble matter is defined by a value measured as follows.

That is, 0.5 to 1.0 g of a resin sample was weighed (w ₁ g), and a cylindrical filter paper (for example, No. 8 made by Toyo Filter Paper) was used.
6R) and subjected to a Soxhlet extractor, extracted with 100 to 200 ml of THF as a solvent for 6 hours, and evaporated a soluble component extracted with the solvent.
Vacuum dried at 00 ° C for several hours, and the THF soluble resin component amount (w
₂ g) is weighed, and the THF-insoluble content is determined by the following equation.

THF insoluble matter (% by weight) = 100 (w ₁ −w ₂ ) / w ₁

Further, the MI ₁₂₅ of the toner of the present invention is 20 or more and 80 or less, and the MI _{125 of} the toner and the MI ₁₂₅ of the binder resin are different.
₁₂₅ is greater than 2 and less than 5, the toner MI ₁₂₅
It is preferable that the difference ΔMI (= toner MI ₁₂₅ −binder resin MI ₁₂₅ ) between the binder resin MI ₁₂₅ and the binder resin MI ₁₂₅ is 7 or more and 50 or less.

The reason why the MI value of the toner falls within this range is as follows.
If the I value is less than 20, the fluidity at the time of heat fixing is not sufficient, and the toner is present in a granular form, and a clear image cannot be obtained. This is because troubles such as toner adhesion to the fixing roller occur. Also, if the ratio of the MI of the toner to the MI of the resin is smaller than 2, the dispersibility of the toner constituent material is deteriorated, and if it is larger than 5, the offset resistance is deteriorated. Also, the difference ΔM between the MI of the toner and the MI of the binder resin
If I is less than 7, the fixability deteriorates, and if I is more than 50, the storage stability deteriorates.

The measuring method of the MI value of the present invention is carried out according to the method A of JIS K7210. However, the measurement conditions of the binder resin and the toner were as follows: temperature 125 ° C., load 10 kg
And the measured value is converted to a 10-minute value.

The specific low molecular weight wax used in the present invention is a hydrocarbon wax having a polar group. The low molecular weight wax preferably used is represented by the following general formula.

R-Y

(R: hydrocarbon group, Y: hydroxyl group, carboxyl group, alkyl ether group, ester group, sulfonyl group) The weight average molecular weight (Mw) of RY by gel permeation chromatography is 3000 or less. Examples of specific compounds include: (A) CH ₃ (CH ₂ ) _n CH ₂ OH (n = about 20 to about 30)
0) (B) CH ₃ (CH ₂ ) _n CH ₂ COOH (n = about 20 to about 300) (C) CH ₃ (CH ₂ ) _n CH ₂ OCH ₂ (CH ₂ ) _m CH ₃ (n = about 20) To about 200, m = 0 to about 100). These compounds are derivatives of the compound (A), and the main chain is a linear saturated hydrocarbon. As long as the compound is derived from the compound (A), those other than those shown in the above examples can be used. By using the above wax, the toner of the present invention can highly satisfy the fixing property at low temperature and the anti-offset property at high temperature.

Among the above-mentioned compounds, (A) Formula (A) CH ₃ (CH ₂ ) _n OH (n = about 20 to about 3)
(00) is preferably used as the main component. The above-mentioned wax has good slip properties and is particularly excellent in offset resistance.

Furthermore, the wax used in the present invention is:
The weight average molecular weight (Mw) is preferably 3000 or less, and preferably, the number average molecular weight (Mn) is 200 or more and 2 or less.
000 or less (preferably 300 or more and 1200 or less), a weight average molecular weight (Mw) of 400 or more and 3000 or less (preferably 800 or more and 2500 or less), and Mw / M
n is preferably 3 or less.

By providing such a molecular weight distribution, it is possible to impart favorable thermal characteristics to the toner.
If the molecular weight is smaller than the above range, thermal effects are excessively likely to occur, and offset, blocking, and the like are likely to occur. When the molecular weight is larger than the above range, the fixability tends to deteriorate.

For the same reason, equations (A), (B),
The number n of (C) is 20 to 300 (more preferably 20 to 2).
00).

By combining the low-molecular-weight wax according to the present invention with the binder resin, the acid component in the binder resin controls the dispersion state of the low-molecular-weight wax. It is presumed that the performance of the low-molecular weight wax itself is exhibited without any loss, and plays a role in improving the performance such as fixing property, offset resistance and developing property and maintaining the performance balance.

These waxes are preferably used in an amount of 0.5 to 20 parts by weight based on 100 parts by weight of the binder resin.

Further, the low molecular weight wax of the present invention
₁₀₀ is 76 or more and 128 or less, and the ratio of MI ₁₀₀ of the low molecular weight wax to MI ₁₂₅ of the binder resin is greater than 8 and 19
It is preferable that the difference ΔMI between MI _{100 of the} smaller and low molecular weight wax and MI ₁₂₅ of the binder resin is 68 or more and 118 or less.

The reason why the MI ₁₀₀ value of the low molecular weight wax is within this range is that if the MI ₁₀₀ value is smaller than 76, a sufficient plasticizing effect cannot be exhibited, and it becomes difficult to fix at a low temperature.
If it is larger, the plasticizing effect becomes too large, and the offset resistance deteriorates. If the ratio of the MI between the low molecular weight wax and the binder resin is less than 8, fixing becomes difficult at low temperatures, and if it is more than 19, the offset resistance deteriorates.
When the difference ΔMI between the low molecular weight wax and the binder resin is smaller than 68, the fixing property is deteriorated, and when it is larger than 118, the storage property is deteriorated.

The MI value is measured according to JIS K721.
The measurement is carried out in accordance with Method A of 0, but the measurement conditions of the low molecular weight wax are a temperature of 100 ° C. and a load of 5 kg, and the measured value is converted into a value for 10 minutes.

When the toner of the present invention has a negative triboelectric charge, an organic metal complex such as a metal salt of a salicylic acid, a metal complex of an alkyl salicylic acid, a metal salt of a dialkyl salicylic acid, or a metal complex of naphthoic acid; Dye; preferably contains a monoazo dye derivative such as a metal complex salt of a monoazo dye.

Examples of the negative charge control agent for the dye compound include, for example, an azo metal complex represented by the following general formula (I).

[0115]

Embedded image

In particular, the charge control agents usable in the present invention are more effective.

[0117]

Embedded image Can be mentioned.

As the negative charge control agent, for example, a basic organometallic complex represented by the following general formula (III) can also be used.

[0119]

Embedded image

In particular, the charge control agents that can be used in the present invention are more effective.

[0121]

Embedded image And a naphthoic acid iron complex represented by

The content of the charge control agent is preferably from 0.1 to 5 parts by weight, particularly preferably from 0.2 to 3 parts by weight, based on 100 parts by weight of the binder resin of the toner. If the proportion of the charge control agent is too large, the fluidity of the toner deteriorates and fogging tends to occur. On the other hand, if the proportion is too small, it is difficult to obtain a sufficient charge amount.

The toner of the present invention preferably contains a magnetic material. Examples of magnetic materials that can be used include magnetite, γ-iron oxide, ferrite, iron oxides such as iron-rich ferrite; metals such as iron, cobalt, and nickel; or these metals and aluminum, cobalt, copper, lead,
Magnesium, tin, zinc, antimony, beryllium,
Examples include alloys with metals such as bismuth, cadmium, manganese, selenium, titanium, tungsten, and vanadium, and mixtures thereof.

The content of the above magnetic material is preferably about 20 to 200 parts by weight, particularly preferably 40 to 150 parts by weight, based on 100 parts by weight of the binder resin of the toner.

As the coloring agent used in the present invention, conventionally known pigments or dyes such as carbon black and copper phthalocyanine are used. Further, even if the magnetic material is a coloring agent, there is no problem.

It is preferable that an inorganic fine powder or a hydrophobic inorganic fine powder is mixed with the toner of the present invention. For example, it is preferable to use silica fine powder or titanium oxide fine powder alone or in combination.

The silica fine powder used in the present invention includes both a so-called dry method produced by a vapor phase oxidation of a silicon halide and a so-called wet silica produced from water glass or the like and a dry silica called a fumed silica. Although it can be used, fumed silica having few silanol groups on the surface and inside and having no production residue is preferable.

Further, the silica fine powder used in the present invention is preferably subjected to a hydrophobic treatment. The hydrophobizing treatment is applied by chemically treating with an organic silicon compound or the like which reacts or physically adsorbs with the silica fine powder. A preferred method is to treat the dry silica fine powder produced by the vapor phase oxidation of the silicon halide compound with a silane coupling agent or simultaneously with the silane coupling agent and an organic silicon compound such as silicone oil. Is mentioned.

Examples of the silane coupling agent used in the hydrophobizing treatment include hexamethyldisilazane, trimethylsilane, trimethylchlorosilane, trimethylethoxysilane, dimethyldichlorosilane, methyltrichlorosilane, allyldimethylchlorosilane, and allylphenyl. Dichlorosilane, benzyldimethylchlorosilane, bromomethyldimethylchlorosilane, α-chloroethyltrichlorosilane, β-chloroethyltrichlorosilane,
Chloromethyldimethylchlorosilane, triorganosilane mercaptan, trimethylsilyl mercaptan, triorganosilyl acrylate, vinyldimethylacetoxysilane, dimethylethoxysilane, dimethyldimethoxysilane, diphenyldiethoxysilane, hexamethyldisiloxane, 1,3-divinyltetramethyldi Siloxane and 1,3-diphenyltetramethyldisiloxane.

Examples of the organosilicon compound include silicone oil. Preferred silicone oils are those having a viscosity of about 30 to 1,000 centistokes at 25 ° C., such as dimethyl silicone oil, methylphenyl silicone oil, α-methylstyrene-modified silicone oil, chlorophenyl silicone oil, and fluorine-modified silicone oil. Silicone oil and the like are preferred.

The inorganic fine powder is preferably used in an amount of 0.1 to 3.0 parts by weight based on 100 parts by weight of the toner.

When the toner of the present invention is used as a two-component developer, non-coated carriers such as iron powder, ferrite powder, magnetite powder, glass beads, styrene-acrylic resin, silicone resin, and fluorine-modified A carrier coated with an acrylic resin or the like, a granulated carrier, or the like can be used.

To produce the toner according to the present invention, the toner constituent materials are melt-kneaded using a mixer such as a ball mill, and then cooled and solidified, and then pulverized and classified to obtain the toner according to the present invention. .

[0134]

Although the basic configuration and features of the present invention have been described above, the present invention will be specifically described below based on embodiments. However, this does not limit the embodiment of the present invention at all. Parts in the examples are parts by weight.

(Synthesis Example 1) Xylene 3 was placed in a reaction vessel equipped with a synthetic distillation column, a stirrer, and a thermometer for the low molecular weight polymer (L).
00 parts were charged. Next, nitrogen gas is introduced into the container while stirring and nitrogen replacement is performed for 90 minutes, and then the temperature is raised to reflux.

Under the reflux, 85 parts of styrene, 15 parts of n-butyl acrylate and 0.25 part of monobutyl maleate are added and stirred while flowing nitrogen gas. Next, a solution of 2 parts of di-tert-butyl peroxide dissolved in 10 parts of xylene is added dropwise over 1 hour. The rate of the addition is gradually reduced, and the amount of the added solution is reduced to about half. At the same time, add 0.05 parts of monobutyl maleate.
The polymerization was completed by holding for 5 hours to obtain a low molecular weight polymer (L) solution.

A part of the polymer solution was sampled,
It dried under reduced pressure and the acid value (Av) of the obtained low molecular weight polymer (L) was measured. As a result, Av was 0.2. The polymerization conversion at this time was 98%.

Synthesis of high molecular weight polymer (H) Degassed water 18 was added to a reaction vessel equipped with a distillation column, a stirrer, and a thermometer.
After adding 0 parts and 20 parts of a 2% by weight aqueous solution of polyvinyl alcohol, 74 parts of styrene, 25 parts of n-butyl acrylate, 5 parts of monobutyl maleate, and 0.005 part of divinylbenzene were added, and the mixture was sufficiently stirred and suspended. A suspension was obtained.

After introducing nitrogen gas into the container and performing nitrogen replacement for 90 minutes, the temperature was raised to 80 ° C. Next, 2,2-bis (4,4-di-tert) dissolved in 10 parts of xylene was used.
A solution of 0.1 part of -butylperoxycyclohexyl) propane (having a half-life of 10 hours and a temperature of 92 ° C) was added dropwise over 2 hours. The rate of the addition was gradually reduced, and the amount of the added solution was about half. When it becomes, add 1 part of monobutyl maleate. The temperature was raised to 86 ° C. to start the polymerization, and the temperature was maintained for 24 hours. After that, the temperature was further raised to 110 ° C. and the temperature was maintained for 3 hours to complete the polymerization.

A part of this polymerization solution was sampled, dried under reduced pressure, and the acid value (Av) of the obtained high molecular weight polymer (H) was measured. As a result, Av = 9.0. .

After the completion of the reaction, the suspension was mixed with an Na equivalent of twice the acid value (Av = 9.0) of the obtained high molecular weight polymer (H).
An OH aqueous solution was added, and the mixture was stirred for 2 hours.

The high molecular weight polymer (H) was separated by filtration, washed with water,
After drying and analysis, the THF insoluble content was 0.7%.
And it was substantially not included.

Resin Production Example 1 100 parts of xylene and 28 parts of the high molecular weight polymer (H) were charged into a reaction vessel equipped with a distillation column, a stirrer, and a thermometer, and the mixture was heated and stirred under reflux. And perform preliminary dissolution. After maintaining in this state for 12 hours, a uniform pre-dissolved solution (Y) of the high molecular weight polymer (H) was obtained.

A part of the pre-dissolved solution was sampled and dried under reduced pressure. The glass transition point (Tg) of the obtained solid was 61 ° C.

On the other hand, the low molecular weight polymer (L) was placed in a separate container.
300 parts of a homogeneous solution of the above is charged and refluxed.

After the pre-dissolved solution (Y) and the low molecular weight polymer (L) solution were mixed under reflux, the organic solvent was distilled off.
The obtained resin was cooled, solidified and then pulverized to obtain a resin-1 for toner shown in Table 1.

When the molecular weight of the resin-1 was measured, it had peaks at 8000 and 690,000, and the Mw of the whole resin was
= 300,000, Mw / Mn = 45, Tg60 ° C, Av
= 2.5. When a thin section of the toner resin was observed with a video microscope (Wilson),
Good dispersion was confirmed without reaggregation of the high molecular weight component.

(Synthesis Examples 2 to 7) Toner resins 2 to 7 shown in Table 1 were obtained in the same manner as in Example 1 except that the charged amount of monobutyl maleate was changed.

(Synthesis Example 8) In a reaction vessel equipped with a distillation column, a stirrer, and a thermometer, 120 parts of deionized water and 0.002 emulsifier, which is a copolymer of methyl methacrylate and 3-sodium sulfopropyl methacrylic acid, were added. Parts were charged and mixed. 17 parts of styrene, n-butyl acrylate 3
, And 0.05 parts of potassium persulfate, and nitrogen gas was introduced into the vessel with stirring to carry out nitrogen replacement for 90 minutes. The temperature was raised to 70 ° C., and emulsion polymerization was performed for about 5 hours.

Next, the reaction system was cooled to about 30 ° C., and a mixture of 100 parts of deionized water, 1 part of polyvinyl alcohol, and 0.05 part of sodium sulfate was added thereto.
12 parts of n-butyl acrylate and 7 parts of monobutyl maleate were charged and impregnated for 1 hour. Next, 5 parts of benzoyl peroxide was charged, the temperature of the reaction system was raised to 85 ° C., and suspension polymerization was performed for 3 hours.

After the temperature of the reaction system was raised to 100 ° C. and maintained for 2 hours, an alkali treatment was performed for 1 hour. Next, after cooling to room temperature, the binder resin was taken out, washed with deionized water, and then sufficiently dried with a drier to obtain a comparative resin shown in Table 1.
1 was obtained.

When the molecular weight of Comparative Resin-1 was measured, it had peaks at 9600 and 800,000, Mw of the entire resin was 320,000, Mw / Mn = 58, and Tg was 65 ° C.
Av = 2.11.

(Synthesis Examples 9 to 12) Comparative resins 2 to 5 shown in Table 1 were obtained in the same manner as in Synthesis Examples except that the amount of monobutyl maleate charged was changed.

Table 2 shows the physical properties of the wax used in the present invention.

[0155]

[Table 1]

[0156]

[Table 2]

Where CH ₃ (CH ₂ ) _n Y: n: integer Y: functional group

[Example 1] 100 parts of resin for toner-1 100 parts of magnetic iron oxide 7 parts of wax-1 (Table 2) 2 parts of charge control agent (formula II)

The mixture was melt-kneaded with a twin-screw extruder heated to 130 ° C., and the cooled kneaded material was coarsely pulverized with a hammer mill, and the coarsely pulverized material was finely pulverized with a jet mill. Was classified with a fixed wall type air classifier to produce a classified powder. Further, the obtained classified powder is strictly classified and removed by a multi-division classifier (Elbow jet classifier manufactured by Nittetsu Mining Co., Ltd.) utilizing the Coanda effect, and the ultrafine powder and coarse powder are simultaneously strictly removed to obtain a weight average diameter (D ₄ ) 6. 0.6 μm (particle size 12.7 μm
(m content of 0.1% of magnetic toner particles).

To 100 parts of the above toner, 1.2% by weight of hydrophobic silica fine powder was added and mixed with a Henschel mixer to obtain a developer shown in Table 3.

[Examples 2 to 15 and Comparative Examples 1 to 6] The toner resin, the magnetic iron oxide, the wax, the charge control agent, and the hydrophobic silica fine powder shown in Table 2 were used in the synthesis examples. By the same method as in Example 1, the developers of Examples 2 to 15 and Comparative Examples 1 to 6 shown in Table 3 were obtained.

Further, the acid values (a, b, c, d) of each part of the GPC chart of the toners of Examples 1 to 15 and Comparative Examples 1 to 6 except that the toner components other than the binder resin were removed were measured. Table 4 shows the results.

Table 5 shows the results of measuring the MI of the toners of Examples 1 to 15 and Comparative Examples 1 to 6.

[0164]

[Table 3]

[0165]

[Table 4]

[0166]

[Table 5]

Next, the image forming apparatus used in this embodiment will be described. Commercial laser beam printer LBP
-SX (manufactured by Canon) as shown in FIG.
An elastic blade made of urethane rubber and a charging roller were attached to the device unit (toner cartridge). Further, a transfer roller was attached to the main body, and the heating and fixing device was further modified into the configuration shown in FIG. 2 (exploded perspective view) and FIG. 3 (cross-sectional view), and set under the following conditions.

An electrostatic latent image is formed by setting the primary charge to -600 V, a gap (300 μm) is set without contact between the photosensitive drum 3 and the developer layer on the developer carrier 6 (including a magnet), and an AC bias ( f = 1500 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 _VL is −
The electrostatic image was developed by reversal development at 150 V to form a toner image on the OPC photoconductor. 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, in the heat fixing device, the surface temperature of the temperature measuring element 21d of the heating body 21 is 135 ° C., the total pressure between the heating body 21 and the pressure roller 23 is 7 kg, and the nip between the pressure roller and the film is 3 m.
m, and the fixing film 22 has P
A 40 μm thick heat-resistant polyimide film having a low-resistance release layer in which a conductive material was dispersed in TEF was used.

Under the above set conditions, room temperature and normal humidity (25 ° C., 6
In a 0% RH environment, a printout test was performed on 7,000 sheets continuously at a print speed of 8 sheets (A4) / min while replenishing the developer, and the obtained images were evaluated for the following items.

Similarly, under a high temperature and high humidity environment (32.5 ° C.,
90% RH) and under low temperature and low humidity environment (10 ° C, 15% R)
In H), an image-drawing test was performed.

In a high temperature and high humidity environment, 6500
After performing the image output test, under the same environment,
The sample was allowed to stand for a day, and an image printing test was further performed for 500 sheets.

(1) Image Density Evaluation was carried out by maintaining the image density at the end of printing out 7,000 sheets on ordinary plain paper for copying machines (75 g / m ² ).
The image density was measured by using a "Macbeth reflection densitometer" (manufactured by Macbeth Co., Ltd.) with respect to a printout image of a white background portion having a document density of 0.00.

(2) Fog Fog was calculated from a comparison between the whiteness of the transfer paper measured with a reflex meter (manufactured by Tokyo Denshoku Co., Ltd.) and the whiteness of the transfer paper after printing solid white.

(3) Image Quality The pattern shown in FIG. 4 was printed out and its dot reproducibility was evaluated.

A: very good (less than 2 defects / 100
○: Good (3-5 defects / 100 defects) △: Normal (6-10 defects / 100 defects) ×: Bad (11 or more defects / 100 defects)

(4) Fixing Property The fixing property was evaluated by applying a load of 50 g / cm ² , rubbing the fixed image with soft thin paper, and reducing the image density before and after rubbing (%).

◎ (excellent): 5% or less, ○
(Good): 5% or more and less than 10% △ (Normal): 10% or more and less than 20%, × (Bad): 2
0% or more

(5) Offset Resistance The offset resistance was evaluated by printing out a sample image having an image area ratio of about 5% and evaluating the degree of stain on the image after 3000 sheets.

◎: very good (not generated), ：: good (almost no occurrence) △: normal, ×: worse than △

(6) Storage Property The storage property was evaluated by visually observing the occurrence of coarse particles after the toner was left at 50 ° C. for 3 days.

◎: very good (not generated) 良好: good (almost not generated) Δ: normal (coarse grains are present, but loosened) ×: worse than Δ (many coarse grains are not loosened)

(7) Sleeve Contamination After the printout test was completed, the state of fixation of the residual toner on the developing sleeve surface and the effect on the printout image were visually evaluated.

◎: Very good (no occurrence) ：: Good (almost no occurrence) Δ: Normal (there is sticking but little influence on the image) ×: Poor (more sticking and image unevenness Arises)

At the same time, the state of the surface of the fixing film was observed to evaluate its durability.

(8) Stain on Drum The occurrence of scratches on the surface of the photosensitive drum and sticking of residual toner and the effect on printout images were visually evaluated.

◎: very good (not generated) 良好: good (slight flaws are observed, but there is no effect on the image) Δ: normal (there is adhesion or flaw, but little effect on the image) ) ×: worse than Δ (many sticking, causing vertical streak-like image defects)

At the same time, the state of the surface of the fixing film was observed to evaluate its durability.

(9) Film Staining After the printout test, the state of fixation of the residual developer on the surface of the fixing film was visually evaluated.

◎: very good (not generated), ：: good (almost no occurrence) Δ: normal, ×: worse than Δ

Table 6 summarizes the above results.

[0191]

[Table 6]

[0192]

As described above, according to the toner for developing an electrostatic image of the present invention, in a toner having at least a binder resin, a low molecular weight wax and a colorant, the binder resin has a low molecular weight component and a high molecular weight. And at least two local maximum values in the GPC chart. The GPC chart of the binder resin is divided into four categories of A, B, C, and D in order of smaller molecular weight by using the maximum value and the minimum value as dividing points. When the acid value of each component is a, b, c and d, the following condition b <a <d <c (Equation 1) is satisfied, so that developability and high image quality stability are good. In addition, fixing at low temperature without impairing offset resistance, and
This has the effect of providing a developer having good storage stability.

[Brief description of the drawings]

FIG. 1 is a schematic explanatory view 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 the fixing device used in the embodiment of the present invention.

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

FIG. 4 is an explanatory diagram of a checker pattern for checking development characteristics of toner.

FIG. 5 is a schematic diagram in which the GPC charts of the binder resins of Production Examples 1 to 12 and Comparative Examples 1 to 4 are divided into four parts by using peaks and valleys as division points.

[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 Cleaning blade 8 Elastic blade 11 Charging means 12 Bias applying means 13 Magnetic developer 14 Cleaning means 15 Magnetic field generating means 20 Stay DESCRIPTION OF SYMBOLS 21 Heating body 21a Heater board 21b Heating body 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 Disconnecting member 28 Inlet guide 29 Exit guide (separation guide)

────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoshihiro Ogawa 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (56) References JP-A-2-5070 (JP, A) JP-A Heisei JP-A-6-348806 (JP, A) JP-A-3-294866 (JP, A) JP-A-3-294867 (JP, A) JP-A-6-273975 (JP, A) A) JP-A-6-208246 (JP, A) JP-A-5-241371 (JP, A) JP-A-5-173363 (JP, A) JP-A-6-130725 (JP, A) JP-A-59 JP-A-159173 (JP, A) JP-A-5-53377 (JP, A) JP-A-4-170557 (JP, A) JP-A-63-188158 (JP, A) JP-A-63-113558 (JP, A) (58) Fields surveyed (Int. Cl. ⁷ , DB name) G03G 9/08

Claims (20)

(57) [Claims] 1. A toner having at least a binder resin, a low molecular weight wax and a colorant, wherein the binder resin has a low molecular weight component and a high molecular weight component, and has at least two components in a GPC (gel permeation chromatograph) chart. The GPC chart of the binder resin is divided into four sections, A, B, C and D, starting from the smaller molecular weight, using the maximum value and the minimum value as dividing points. Wherein a, b, c, and d satisfy the following conditions. b <a <d <c (Equation 1) 2. The GPC chart of the binder resin is divided into A, B, and C from the smaller molecular weight by using a maximum value and a minimum value as dividing points.
And D, and the acid values of the components in each section are a,
2. The electrostatic image developing toner according to claim 1, wherein the following conditions are satisfied when b, c and d are satisfied. 0.05 ≦ a + b ≦ 2 (Equation 2) 5 ≦ c + d ≦ 15 3. The peak molecular weights of two maximum values and one minimum value of a GPC chart of the binder resin are represented by P ₁ ,
The electrostatic image developing toner according to claim 1, wherein P ₂ and P ₃ satisfy the following conditions. 3000 ≦ P ₁ ≦ 20,000 300,000 ≦ P ₂ ≦ 1.3 million 40,000 ≦ P ₃ ≦ 150,000 (formula 3) 4. The glass transition point (Tg) of the binder resin is 5
The electrostatic image developing toner according to any one of claims 1 to 3, wherein the temperature is 5 ° C or higher and 65 ° C or lower. 5. The electrostatic image developing toner according to claim 1, wherein the binder resin has a THF-insoluble content of 5% by weight or less. 6. The electrostatic charge according to claim 1, wherein the binder resin is a vinyl resin, and the acid value of the binder resin is 0.06 or more and 14 or less. Image developing toner. 7. The electrostatic charge according to claim 1, wherein the binder resin is a vinyl resin, and the acid value of the binder resin is 0.5 or more and 8 or less. Image developing toner. 8. The electrostatic image development according to claim 1, wherein the binder resin is a vinyl resin, and the acid value of the binder resin is 1 or more and 4 or less. For toner. 9. The melt index MI _{125 of the} toner.
(125 ° C., 10 kg load) is 20 to 80, and the MI _{125 of the} toner and the MI ₁₂₅ (125 ° C., 1
The toner for developing an electrostatic charge image according to any one of claims 1 to 8, wherein the ratio (0 kg load) satisfies the following condition. 2 MI ₁₂₅ ≦ of MI ₁₂₅ / binder resin of ≦ toner 5 (Equation 4) 10. The MI _{125 of the} toner and the M of the binder resin.
The difference ΔMI of I ₁₂₅ (= toner MI ₁₂₅ −binder resin M)
I ₁₂₅ ) is 7 to 50.
3. The toner for developing an electrostatic image according to item 1. 11. The low molecular weight wax contains a compound represented by the following general formula: RY (R: hydrocarbon group, Y: hydroxyl group, carboxyl group, alkyl ether group, ester group, sulfonyl group), The weight average molecular weight (Mw) of R-Y measured by GPC is 3,000 or less.
The toner for developing electrostatic images according to any one of the above. 12. The low molecular weight wax has a number average molecular weight (Mn) of 200 or more and 2000 or less, a weight average molecular weight (Mw) of 400 or more and 3000 or less, and Mw /
The electrostatic image developing toner according to claim 11, wherein Mn is 3 or less. 13. The method according to claim 11, wherein the low-molecular-weight wax contains an aliphatic alcohol represented by CH ₃ (CH ₂ ) _n OH (n = 20 to 300) as a main component. An electrostatic image developing toner. 14. The low molecular weight wax having an MI ₁₀₀ (10
(0 ° C., 5 kg load) is 76 to 128, and the low molecular weight wax MI ₁₀₀ and the binder resin MI ₁₂₅ (125
The toner for developing an electrostatic image according to any one of claims 1 to 13, wherein the ratio (C, 10 kg load) satisfies the following condition. 8 ≦ low molecular weight wax MI ₁₀₀ / binder resin MI ₁₂₅ ≦ 19 (Formula 5) 15. The difference of the MI ₁₂₅ of the low molecular weight wax MI ₁₀₀ and the binder resin ΔMI (= low molecular weight wax MI ₁₀₀
- The toner according to claim 14, wherein the binder resin MI ₁₂₅₎ is 68 to 118. 16. The toner according to claim 1, wherein the toner contains an azo-based metal complex compound represented by the following formula.
16. The electrostatic image developing toner according to any one of items 15 to 15. Embedded image 17. The toner according to claim 16, wherein the toner contains an azo-based iron complex compound represented by the following formula.
3. The toner for developing an electrostatic image according to item 1. Embedded image 18. The toner for developing an electrostatic image according to claim 1, wherein the toner contains a basic organometallic complex represented by the following formula. Embedded image 19. The toner for developing an electrostatic charge image according to claim 18, wherein the toner contains a basic organic iron complex represented by the following formula. Embedded image 20. The electrostatic image developing toner according to claim 1, wherein the toner contains a magnetic material.