JPH1073950A - Toner for electrostatic charge image development - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a toner for electrostatic charge image development excellent in a low temperature fixing property and an offset resistance property and preventing production of blotches due to toner coating uniformity failure on a toner carrier. SOLUTION: A toner for electrostatic charge image development including at least biding resin, wax and a magnetic body has at least one maximal value or shoulder in each of the regions of a region of molecular weight 300-800 and a region of 800-7,000 and the magnetic body is magnetic iron oxide including at least one or more than one of elements selected from the elements of lithium, beryllium, boron, magnesium, aluminium, silicon, phosphorus, germanium, titanium, zirconium, tin and zinc in a chromatogram measured by a GPC(jell permeation chromatography) of wax.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrostatic image developing toner used in electrophotography, electrostatic recording, and 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 Publication No. JP-A-Heisei, 43-24878 and Japanese Patent Publication No. 43-24748. Generally, a photoconductive substance is used to form an electric latent image on a photoreceptor by various means. Forming and then developing the latent image with toner,
After transferring the toner image to a transfer material such as paper as necessary,
The toner is fixed by heating, 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 copying apparatuses have begun to be used not only as office work copying machines for simply copying original documents, but also as printers as personal computer outputs or personal copying machines for individuals. .

[0004] For this reason, smaller, lighter, faster, more energy-saving, and higher reliability have been strictly pursued, and machines have been constructed with simpler elements in various points. As a result, the performance required of the toner has become higher, and if the performance of the toner cannot be improved, a better machine cannot be realized.

For example, various methods and apparatuses have been developed for fixing a toner image to a sheet such as paper. For example, there are a compression 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, the toner is fixed by allowing the toner image surface of the sheet to be fixed to pass through the surface of the heat roller or the film formed of a material having a releasable property to the toner. Is performed. In this method, since the surface of the heat roller or the film comes into contact with the toner image of the sheet to be fixed, 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. Very good in electrophotographic copiers. However, in the above method, a part of the toner image adheres to and transfers to the fixing roller or film surface because the heat roller or the film surface and the toner image come into contact in a molten state, and the toner image re-transfers to the next sheet to be fixed. A so-called offset phenomenon occurs, and the sheet to be fixed may be stained. Preventing toner from adhering to the heat fixing roller or the film surface is one of the essential conditions of the heat fixing method.

Conventionally, for the purpose of preventing toner from adhering to the surface of a fixing roller, for example, the surface of the roller is formed of a material having excellent releasability with respect to the toner, such as silicone rubber or a fluorine-based resin, and the surface of the roller is further prevented from offsetting. 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. Although this method is extremely effective in preventing toner offset, it has a problem that a fixing device is required because a device for supplying an anti-offset liquid is required.

[0008] This is in the opposite direction of miniaturization and weight reduction, and moreover, silicone oil and the like may evaporate due to heat and contaminate the inside of the machine. Therefore, instead of using a silicone oil supply device, instead of supplying the anti-offset liquid during heating from the toner, a method of adding a release agent such as low molecular weight polyethylene or low molecular weight polypropylene to the toner is proposed. Have been. If a large amount of such an additive is added in order to obtain a sufficient effect, the developability is deteriorated and the surface of the toner carrier such as a carrier or a sleeve is contaminated, and the image is deteriorated, which is a practical problem. Therefore, a small amount of release agent is added to the toner to such an extent that the image is not deteriorated, and a small amount of release oil is supplied or the offset toner is cleaned by a roll-up type device using a member such as a web. It has been used together.

However, in view of recent demands for miniaturization, weight reduction, energy saving, and high reliability, it is necessary and preferable to remove even these auxiliary devices. Therefore, it is not possible to cope without further improvement in performance such as toner fixing property and anti-offset property.
It is difficult to realize without further improvement of the release agent.

In order to improve the fixability of the toner, GPC
In a chromatogram measured by the method described in JP-A-5-19531 and JP-A-5-241370, a toner having two or more peaks having different molecular weights and using a binder resin having specific rheological properties can be used. Japanese Unexamined Patent Publication, JP-A-6-27722 and the like are disclosed.

However, even with these toners, the fixing temperature range corresponding to the high speed and energy saving of the copying apparatus, particularly the low temperature fixing property, is insufficient, and further improvement is required.

It is known to include wax as a release agent in a toner. For example, JP-A-52-330
No. 4, JP-A-52-3305, JP-A-57-3305.
Japanese Patent Laid-Open Nos. 52574, 6-324513, and 7-36210 disclose techniques.

[0013] These waxes are used to improve the offset resistance of the toner at low and high temperatures. However, these properties could not be improved at the same time, the blocking resistance deteriorated, and the developability deteriorated.

A toner containing two or more types of wax in order to exert the effect of adding wax from a low temperature region to a high temperature region is disclosed in, for example, Japanese Patent Publication No.
3305, JP-A-58-215659, JP-A-62-100775, JP-A-4-12467.
No. 6, JP-A-4-299357, JP-A-4-299357
JP-A-358159, JP-A-4-362953,
JP-A-6-130714, JP-A-6-33224
A technology such as Japanese Patent Publication No. 4 is disclosed.

[0015] However, none of these toners can satisfy all the performances, and some problems have arisen. For example, the high-temperature offset resistance is excellent, but the low-temperature fixing property is one step away, or the low-temperature offset resistance and the low-temperature fixing property are excellent, but the blocking resistance is slightly inferior and the developing property is deteriorated. There have been adverse effects, inadequate offset resistance at low and high temperatures, and non-uniform toner coating due to free wax components, causing blotches and image defects.

[0016] The wax contained in these toners satisfies the above-mentioned performance because the wax component exists only in a wide or deviated molecular weight distribution region with respect to a chromatogram measured by GPC. This is because they contained many components that were insufficient or deteriorated or had little effect.

[0017]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the above problems.

That is, an object of the present invention is to provide a toner for developing an electrostatic image having a wide fixing temperature range, which is excellent in low-temperature fixing property and offset resistance.

It is a further object of the present invention to provide a toner for developing electrostatic images which has excellent blocking resistance and does not deteriorate developability.

It is a further object of the present invention to provide a toner for developing an electrostatic image in which a free wax component is reduced and no blotch occurs due to poor uniformity of toner coat on a toner carrier of a developing device.

[0021]

According to the present invention, there is provided a toner for developing an electrostatic image containing at least a binder resin, a wax and a magnetic substance, wherein a chromatogram of the wax measured by GPC (gel permeation chromatography) is used. Having at least one maximum or shoulder in each of a region having a molecular weight of 300 to 800 and a region having a molecular weight of 800 to 7,000, wherein the magnetic substance is lithium, beryllium, boron, magnesium, aluminum, silicon, phosphorus, germanium. And a magnetic iron oxide containing at least one element selected from the group consisting of titanium, zirconium, tin and zinc.

Further, in the chromatogram measured by GPC of the wax, the wax may have at least one maximum value or shoulder in each of the region having a molecular weight of 350 to 750 and the region having a molecular weight of 900 to 5,000. preferable.

Further, in the chromatogram of the toner measured by GPC, at least one maximum value or shoulder is present in each of a region having a molecular weight of 300 to 3,000 and a region having a molecular weight of 3,500 to 50,000. However, it is preferable to have at least one maximum value or shoulder in a region having a molecular weight of 100,000 or more.

Further, the present invention relates to a toner for developing an electrostatic charge image, characterized in that a binder resin is dissolved in a solvent, the wax is added and mixed, the solvent is removed, and the wax is dried. It is.

More preferably, the wax has a molecular weight of 300 to 8 in a chromatogram measured by GPC.
The maximum peak height (H ₁ ) of the low molecular weight side region has at least one maximum value or shoulder in each of the region of 00 and the region of 800 to 7,000.
And H ₁ > H ₃ , H ₃ between the height of the maximum peak (H ₃ ) in the high molecular weight region and the height of the minimum value (H ₂ ) between the two peaks.
By satisfying the relationship of ≧ H ₂ , H ₁ > H ₂ , the object can be achieved.

[0026]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, the reasons for achieving the above object can be understood by analyzing the data of chromatograms measured by GPC of the wax and the toner.

In the chromatogram of the wax contained in the toner of the present invention measured by GPC, a region having a molecular weight of 300 to 800 (preferably a molecular weight of 350 to 7) is used.
50 region), the component constituting the maximum value in the low molecular weight side region of the wax component is melted at a relatively low temperature, and the low molecular weight component of the binder resin is resistant to the low molecular weight component. A remarkable plasticizing effect is provided without deteriorating the blocking property, and the low-temperature offset resistance and the low-temperature fixability are dramatically improved.

Here, in the chromatogram measured by GPC, when the position of the maximum value in the low molecular weight side region of the wax is less than 300 in molecular weight, the blocking resistance is deteriorated and the image density becomes unstable. .

In the chromatogram measured by GPC, when the position of the maximum value in the low molecular weight region of the wax exceeds 800, the sufficient plasticizing effect on the binder resin cannot be obtained, Does not improve fixability.

In the chromatogram of the wax contained in the toner of the present invention measured by GPC, a region having a molecular weight of 800 to 7000 (preferably a molecular weight of 900 to 7000) is used.
By having at least one maximum value or shoulder in the region (5000 region), the high molecular weight component of the binder resin secures a certain degree of offset resistance, and the component constituting the maximum value in the high molecular weight side region of the wax is compared. Since it melts at a very high temperature to exhibit a releasing effect, it compensates for insufficient performance of high-temperature offset resistance due to a decrease in toner melt viscosity due to a plastic effect, and provides good high-temperature offset resistance.

Further, in the chromatogram measured by GPC, when the position of the local maximum value in the high molecular weight side region of the wax is less than 800, the components constituting the local maximum value in the high molecular weight side region of the wax are compared. Since the resin melts before reaching a very high temperature, a sufficient release effect cannot be obtained, and good offset resistance cannot be maintained.

Further, in the chromatogram measured by GPC, when the position of the maximum value in the high molecular weight region of the wax exceeds the molecular weight of 7000, the melt viscosity becomes too high, and the melt viscosity of the toner due to the plastic effect is too high. Since a sufficient releasing effect cannot be exhibited in accordance with the occurrence of the high-temperature offset accompanying the decrease, the high-temperature offset resistance deteriorates as a result.

Also, since the free wax component increases,
The uniformity of the toner coat on the toner carrier of the developing device is impaired, and the phenomenon of so-called blotching, which results in a partially non-uniform coat, is likely to occur, resulting in image defects.

In the chromatogram of the toner of the present invention measured by GPC, the molecular weight is 300 to 3,000.
Area, 3,500 to 50,000 area and 100,
Having at least one maximum or shoulder in each of the 000 or more regions provides a molecular weight of 100,
The components in the region of 000 or more ensure high-temperature offset resistance and blocking resistance, and have a molecular weight of 3,500 to 50,000.
After obtaining a certain degree of low-temperature fixability with the components in the region, the components having a molecular weight of 300 to 3,000 appearing by the addition of the wax or the low-molecular-weight polyester resin can further improve the low-temperature fixability without impairing the blocking resistance. Can be improved.

The preferred ranges of the respective ranges are molecular weights of 500 to 2,000, 4,500 to 30,000, 10
It is in the range of 000 to 1,000,000, so that better fixing properties, offset resistance and blocking resistance can be obtained.

Here, in the chromatogram measured by GPC, the position of the maximum value of the toner is the molecular weight of 30.
There is no maximum in the range of 0 to 3,000, and the molecular weight is 30.
When it is less than 0, the blocking resistance is significantly deteriorated, and when it is not in the molecular weight region of 300 to 3,000, the low-temperature fixability is not improved.

Further, in the chromatogram measured by GPC, the position of the maximum value of the toner is the molecular weight of 3,5.
When the maximum value does not exist in the region of 00 to 50,000 and exists only in the region having a molecular weight of 3,500 or less, the anti-blocking property and the high-temperature offset resistance deteriorate, and it exists only in the region of 50,000 or more. In this case, the low-temperature fixability deteriorates.

Further, in the chromatogram measured by GPC, the position of the maximum value of the toner is the molecular weight of 10
When there is no maximum value or shoulder in the region of 000 or more and only in the region having a molecular weight of less than 100,000, high-temperature offset resistance and blocking resistance are deteriorated, and the compound is present in the region of molecular weight of 1,000,000 or more. In this case, the low-temperature fixability may be poor.

Preferably, the binder resin dissolved in a solvent is used. The wax is added to the solvent, mixed with the solvent, and the solvent is removed and dried.

In order to incorporate the wax into the toner according to the present invention, the wax, the binder resin and other additives are thoroughly mixed by a mixer such as a ball mill and then heated by a heat roll, kneader, extruder or the like. Melting using a kneader,
After kneading and kneading, the resins are mutually dissolved, and after cooling and solidification, pulverization is performed.

When two or more kinds of waxes are contained, the waxes are melted and mixed in advance with stirring at a temperature not lower than the wax melting temperature, cooled, solidified, and then pulverized.

The binder resin is dissolved in a solvent, the temperature of the resin solution is raised, wax is added and mixed with stirring, the solvent is removed, dried, and then pulverized. And the like. Preferably, the method is good in terms of the dispersibility of the wax in the toner. In the method, the effect on the fixing property can be more exhibited, the developing property is stable, and the change in the image density is small.

Particularly preferably, the chromatogram measured by GPC of the wax has a molecular weight of 300 to 300.
The maximum peak height (H ₁ ) of the low molecular weight region having at least one maximum or shoulder in each of the region of 800 and the region of 800 to 7,000.
And H ₁ > H ₃ , H ₃ between the height of the maximum peak (H ₃ ) in the high molecular weight region and the height of the minimum value (H ₂ ) between the two peaks.
The relationship of ≧ H ₂ , H ₁ > H ₂ is preferably satisfied, more preferably H ₁ : H ₂ : H ₃ = 1.5 to 50: 1: 1 to 20, and further H ₁ : H ₂ : H ₃ = 2 to 50: 1: 1.5 to
15 is preferred. Here, when H ₁ = H ₂ , the low molecular weight side becomes a shoulder, and when H ₃ = H ₂ , the high molecular weight side becomes a shoulder.

As a result, the molecular weight of the wax component, which does not contribute to both the low-temperature fixability and the offset resistance, is reduced, and the molecular weight distribution is such that more wax components can exist in an appropriate amount for the molecular weight at which each function is exhibited. Since the effect of the wax component is small or the excess wax component is reduced as a free wax component, the phenomenon of blotching is less likely to occur.

The chromatogram of the toner of the present invention measured by GPC shows a molecular weight of 3,500 to 50,
Although there is no particular limitation on the method for having at least one maximum or shoulder in each of the 000 region and the 100,000 or more region, for example, in the GPC chromatogram, the region having a molecular weight of 3,500 to 50,000 is used. A low molecular weight polymer having a maximum value of molecular weight, a high molecular weight polymer having a maximum value of molecular weight in a region having a molecular weight of 100,000 or more, or a cross-linked polymer, and two or more kinds thereof are previously prepared. After adjusting the amount of coalescence, dissolving or swelling in a solvent capable of dissolving the polymer or a solvent capable of swelling and mixing, the binder resin obtained by removing the solvent is used in melt kneading during toner production. The chromatogram may be adjusted so as to fall within the range of the present invention, or the amount of each of the polymers may be adjusted so that the chromatogram may be adjusted in melt kneading during the production of toner. It may be adjusted so as to be in the range.

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

For example, homopolymers of styrene such as polystyrene, poly-p-chlorostyrene and polyvinyltoluene and their substituted products; styrene-p-chlorostyrene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene Copolymer, styrene-acrylate copolymer, styrene-methacrylate copolymer, styrene-α-chloromethyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-
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, phenolic resin, natural modified phenolic resin, natural resin modified maleic acid resin, acrylic resin, methacrylic resin, polyvinyl acetate, silicone resin, polyester resin, polyurethane, polyamide resin, furan resin, epoxy resin , Xylene resin, polyvinyl butyral, terpene resin, coumarone indene resin, petroleum resin and the like can be used. Preferred binder resins include styrene copolymers and polyester resins.

The comonomer for the styrene monomer of the styrene copolymer is, 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, acrylonitrile, methacrylonitrile, acrylamide, and the like;
For example, dicarboxylic acids having a double bond such as maleic acid, butyl maleate, methyl maleate, dimethyl maleate and the like;
Vinyl esters such as vinyl acetate and vinyl benzoate; ethylene-based olefins such as ethylene, propylene, butylene; vinyl ketones such as vinyl methyl ketone and vinyl hexyl ketone; vinyl methyl ether and vinyl Vinyl monomers such as ethyl ether, vinyl isobutyl ether and the like; and vinyl monomers such as one or two or more are used.

The styrene-based polymer or styrene-based copolymer may be cross-linked, or may be a mixed resin.

As the crosslinking agent for the binder resin, a compound having two or more polymerizable double bonds may be mainly used. For example, aromatic divinyl compounds such as divinylbenzene, divinylnaphthalene and 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, divinyl ether, divinyl sulfide and divinyl sulfone; and 3
Compounds having at least two vinyl groups are used alone or as a mixture.

The method for synthesizing the styrenic copolymer may be any of bulk polymerization, solution polymerization, suspension polymerization and emulsion polymerization.

In the bulk polymerization method, a polymer having a low molecular weight 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 preferable to obtain a low molecular weight polymer having a maximum molecular weight in a molecular weight range of 5,000 to 100,000 in the chromatogram of C.

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. It is appropriately selected depending on the polymer to be polymerized.

The reaction temperature depends on the solvent used, the initiator and the polymer to be polymerized.
It is better to carry out at 0 ° C. In solution polymerization, solvent 100
It is preferable to carry out with 30 parts by weight to 400 parts by weight of the monomer based on parts by weight.

Further, it is preferable to mix another polymer in the solution at the end of the polymerization, and several kinds of polymers can be mixed well.

Further, as a polymerization method for obtaining a high molecular weight polymer or a crosslinked polymer having a maximum molecular weight in a region having a molecular weight of 100,000 or more in a GPC chromatogram,
Emulsion polymerization and suspension polymerization are preferred.

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 carried out using a water-soluble polymerization initiator. . In this method, it is easy to control the heat of reaction, and since the phase in which the polymerization is carried out (the oil phase composed of the polymer and the monomer) and the aqueous phase are different, the termination reaction rate is small, and as a result, the polymerization rate is large. , With a high degree of polymerization.
Further, the reason is that the polymerization process is relatively simple, and that the polymerization product is fine particles, so that it is easy to mix with a colorant, a charge control agent, and other additives in the production of a toner. This is advantageous as compared with other methods as a method for producing a binder resin for a toner.

However, the resulting polymer tends to be impure due to the added emulsifier, and an operation such as salting out is required to take out the polymer. Therefore, suspension polymerization is a simple method.

In the 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). 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 type of initiator, any initiator that is insoluble or hardly soluble in water can be used.

The initiators used in these polymerization methods include t-butyl peroxy-2-ethylhexanoate, cumin perpivalate, t-butyl peroxy laurate, benzoyl peroxide, lauroyl peroxide, octa-peroxy. Noyl peroxide, di-t-butyl peroxide, t-butylcumyl 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-butyl4,4-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-butylperoxydimethylglutarate, di-t-butylperoxyhexa Hydroterephthalate, di-t-butylperoxyazelate, 2,5-dimethyl-2,5-di (t-
Butyl peroxy) hexane, diethylene glycol
Bis (t-butylperoxycarbonate), di-t-
Butyl peroxytrimethyl adipate, tris (t-
(Butylperoxy) triazine, vinyltris (t-butylperoxy) silane, etc., which can be used alone or in combination.

The amount used is 0.05 parts by weight or more (preferably 0.1 to 15 parts by weight) with respect to 100 parts by weight of the monomer.

The composition of the polyester resin used in the present invention is as follows.

Examples of the dihydric alcohol component include ethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, diethylene glycol, triethylene glycol and 1,5-pentanediol. , 1,6-hexanediol, neopentyl glycol, 2-ethyl-1,3-
Hexanediol, hydrogenated bisphenol A, and bisphenol represented by formula (A) and derivatives thereof;

[0064]

Embedded image

(Wherein R is an ethylene or propylene group, x and y are each an integer of 0 or more, and
The average value of x + y is 0-10. )

Diols represented by the formula (B):

[0067]

Embedded image

(Wherein R ′ is —CH ₂ CH ₂ — or

[0069]

Embedded image X 'and y' are integers of 0 or more, and x '
The average value of + y 'is 0 to 10. ).

Examples of the divalent acid component include phthalic acid,
Benzenedicarboxylic acids such as terephthalic acid, isophthalic acid and phthalic anhydride or their anhydrides and lower alkyl esters; alkyl dicarboxylic acids such as succinic acid, adipic acid, sebacic acid and azelaic acid or their anhydrides and lower alkyl esters; n- Alkenyl succinic acids or alkyl succinic acids such as dodecenyl succinic acid, n-dodecyl succinic acid, or anhydrides and lower alkyl esters thereof; fumaric acid, maleic acid, citraconic acid, unsaturated dicarboxylic acids such as itaconic acid or anhydrides, lower acids And dicarboxylic acids such as alkyl esters; and derivatives thereof.

Further, it is preferable to use a trivalent or higher valent alcohol component and a trivalent or higher valent acid component which also function as a crosslinking component.

The polyhydric alcohol component having three or more valences includes
For example, sorbitol, 1,2,3,6-hexanetetrol, 1,4-sorbitan, pentaerythritol, dipentaerythritol, tripentaerythritol,
1,2,4-butanetriol, 1,2,5-pentanetriol, glycerol, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane, 1,
3,5-trihydroxybenzene and the like.

The trivalent or higher valent polycarboxylic acid component in the present invention includes, for example, trimellitic acid, pyromellitic acid, 1,2,4-benzenetricarboxylic acid,
2,5-benzenetricarboxylic acid, 2,5,7-naphthalenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, 1,2,4-butanetricarboxylic acid, 1,2,2
5-hexanetricarboxylic acid, 1,3-dicarboxyl-2-methyl-2-methylenecarboxypropane, tetra (methylenecarboxyl) methane, 1,2,7,8-
Octanetetracarboxylic acid, empol trimer acid, and anhydrides and lower alkyl esters thereof;

[0074]

Embedded image

(Wherein X is an alkylene or alkenylene group having 5 to 30 carbon atoms having at least one side chain having 3 or more carbon atoms), and their anhydrides and lower alkyl esters And polyvalent carboxylic acids and derivatives thereof.

The alcohol component used in the present invention is 40 to 60 mol%, preferably 45 to 55 mol%.
%, 60 to 40 mol% as an acid component, preferably 5%
It is preferably from 5 to 45 mol%.

The content of the trivalent or higher polyvalent component is preferably 1 to 60 mol% of all components.

The polyester resin can also be obtained by generally known condensation polymerization.

In the toner according to the present invention, in addition to the above-mentioned binder resin component, the following compounds may be contained at a ratio smaller than the content of the binder resin component. For example, silicone resin, polyester, polyurethane, polyamide, epoxy resin, polyvinyl butyral, rosin, modified rosin,
Examples include terpene resins, phenolic resins, and copolymers of two or more α-olefins.

The glass transition point (Tg) of the binder resin used in the toner of the present invention is preferably 45 to 80 ° C., more preferably 50 to 70 ° C.

In the present invention, the binder resin and the toner G
The molecular weight distribution of the chromatogram by PC is measured under the following conditions (as an example, FIG. 3 shows an example of a GPC chromatogram of the toner of Example 7 of the present invention measured under the following conditions).

That is, the column was stabilized in a heat chamber at 40 ° C., THF (tetrahydrofuran) as a solvent was flowed through the column at this temperature at a flow rate of 1 ml / min, and about 100 μl of a THF sample solution was injected. Measure. In measuring the molecular weight of the sample, the molecular weight distribution of the sample was calculated from the relationship between the logarithmic value of a calibration curve prepared from several kinds of monodisperse polystyrene standard samples and the count number. As a standard polystyrene sample for preparing a calibration curve, for example, one having a molecular weight of about 10 ² to 10 ⁷ manufactured by Tosoh Corporation or Showa Denko KK is used.
It is appropriate to use about a few standard polystyrene samples. An RI (refractive index) detector is used as the detector.
As the column, a plurality of commercially available polystyrene gel columns are preferably combined, and for example, showex GPC KF-801, 802, 80 manufactured by Showa Denko KK
3,804,805,806,807,800P or TSKgelG1000H (H
_{XL), G2000H (H XL)} , G3000H (H XL),
_{G4000H (H XL), G5000H (} H XL), G60
00H (H _XL ), G7000H (H _XL ), TSKgua
rdcolumn can be mentioned.

A sample is prepared as follows.

After placing the sample in THF and leaving it to stand for several hours, it is shaken well, mixed well with THF (until the sample is no longer united), and left still for 12 hours or more. Then T
The time of leaving in HF is set to 24 hours or more.
After that, the sample processing filter (pore size 0.45
0.5 μm, for example, Myshoridisk H-25
-5 (manufactured by Tosoh Corporation, Exiclodisk 25CR manufactured by Germanic Science Japan) can be used as a GPC sample. The sample concentration is adjusted so that the resin component is 0.5 to 5 mg / ml.

In the chromatogram of the toner of the present invention measured by GPC, the molecular weight was 300 to 3,
Although there is no particular limitation on the method for having at least one maximum value in the region of 000, for example, polyvinyl chloride, a phenolic resin which is a wax or a low molecular weight resin,
Naturally modified phenolic resin, naturally 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, etc., preferably using waxes, particularly preferably using a hydrocarbon wax which may have a functional group, such that the chromatogram is in the range. It may be adjusted.

The wax contained in the toner of the present invention is:
Low-molecular-weight polyethylene, low-molecular-weight polypropylene, copolymers of olefins, microcrystalline wax, paraffin wax, aliphatic hydrocarbon-based waxes such as Sasol wax; oxides of aliphatic hydrocarbon-based waxes such as oxidized polyethylene wax; or Examples thereof include block copolymers thereof; waxes mainly containing a fatty acid ester such as carnauba wax and montanic acid ester wax; and those obtained by partially or entirely deoxidizing fatty acid esters such as deoxidized carnauba wax. Further, saturated straight-chain fatty acids such as palmitic acid, stearic acid, montanic acid, and long-chain alkyl carboxylic acids having a longer-chain alkyl group; unsaturated fatty acids such as brandinic acid, eleostearic acid, and barinaric acid Saturated alcohols such as stearin alcohol, aralkyl alcohol, behenyl alcohol, carnaubyl alcohol, seryl alcohol, melisyl alcohol, or long-chain alkyl alcohols having a longer-chain alkyl group; polyhydric alcohols such as sorbitol; Fatty acid amides such as acid amide, oleic acid amide and lauric acid amide; methylene bisstearic acid amide;
Saturated fatty acid bisamides such as ethylenebiscapric acid amide, ethylenebislauric acid amide, hexamethylenebisstearic acid amide, ethylenebisoleic acid amide, hexamethylenebisoleic acid amide, N, N '
Unsaturated fatty acid amides such as dioleyl adipamide, N, N'-dioleyl sebacic amide; m-
Aromatic bisamides such as xylene bisstearic acid amide and N, N'-distearyl isophthalic acid amide;
Fatty acid metal salts such as calcium stearate, calcium laurate, zinc stearate and magnesium stearate (commonly referred to as metallic soaps); grafted onto aliphatic hydrocarbon waxes with vinyl monomers such as styrene and acrylic acid Waxes;
Examples include partial esterified products of fatty acids such as behenic acid monoglyceride and polyhydric alcohols; and methyl ester compounds having a hydroxyl group obtained by hydrogenation of vegetable oils and the like.

The wax preferably used is a low-molecular-weight alkylene polymer obtained by radical polymerization of alkylene under high pressure or a low-pressure polymerization using a Ziegler catalyst or another catalyst, or an alkylene obtained by thermally decomposing a high-molecular alkylene polymer. Polymers, low-molecular-weight alkylene polymers produced as by-products when polymerizing alkylene polymers are separated and purified, from the distillation residue of hydrocarbons obtained by the Atage method from synthesis gas consisting of carbon monoxide and hydrogen, or hydrogenated from these A wax obtained by extracting and separating a specific component from a synthetic hydrocarbon or the like obtained by the above method may be used, and an antioxidant may be added. Alternatively, it is a linear alcohol, fatty acid, acid amide, ester or montan derivative. It is also preferable that impurities such as fatty acids have been removed in advance.

Among them, preferred are those obtained by polymerizing olefins such as ethylene, and by-products at this time, such as Fischer-Tropsch wax, whose bases are hydrocarbons having up to about several thousands of carbon atoms. Further, a long-chain alkyl alcohol having a hydroxyl group at a terminal having a carbon number of up to about several hundreds is also preferable. Further, those obtained by adding an alkylene oxide to an alcohol are also preferably used.

Then, from these waxes, the waxes are subjected to a press sweating method, a solvent method, a vacuum distillation, a supercritical gas extraction method, a fractional crystallization (for example, melt liquid crystal precipitation and crystal filtration), and the like to obtain a wax having a molecular weight. A wax that has been fractionated and has a sharp molecular weight distribution is more preferable because the proportion of components in the necessary melting behavior range increases. Above all, the use of two or more kinds of waxes separated in this way is difficult for low-temperature fixing property, blocking resistance and high-temperature offset resistance.
It is particularly preferable in that a wax component having a melting behavior range necessary for improving these properties in a well-balanced manner can be contained in the toner without waste.

In the case where the toner of the present invention contains two or more kinds of the wax, the maximum value of the chromatogram measured by GPC of the wax is compared, and at least one kind of the wax has, for example, a molecular weight. 100
0.5 to 1,200 maximum wax in the region
20 parts by weight (preferably 1 to 10 parts by weight), and at least one kind is, for example, 0.5 to 15 parts by weight (preferably 1 to 8 parts by weight) of a wax having a maximum value in a molecular weight range of 800 to 10,000. It is good to contain.

Further, 0.1 to 10 parts by weight (preferably 0.5 to 5 parts by weight) of a wax having another molecular weight region may be contained.

As a result, the low-temperature fixability and the offset resistance performance can be effectively improved without impairing the blocking resistance.

In the toner of the present invention, the total content of these waxes is 1 to 2 with respect to 100 parts by weight of the binder resin.
It is used in an amount of 5 parts by weight, preferably 2 to 10 parts by weight.

The wax contained in the toner of the present invention is:
With respect to the chromatogram measured by GPC of the wax, Mw is 200 to 10,000 (preferably 40 to
0 to 4,000) and Mw / Mn of 10 or less (preferably 6 or less), the molecular weight distribution of each wax component is sharper, so that low-temperature fixability, blocking resistance and offset resistance are effected. It does not contain unnecessary components for improving the quality of the product, and can satisfy the object of the present invention.

In the present invention, the molecular weight distribution of the wax is G
It is measured under the following conditions by PC (as specific examples, GPC chromatograms of the wax compositions used in Examples 1 and 7 of the present invention measured under the following conditions are shown in FIGS. 1 and 2).

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

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

The toner of the present invention preferably contains a charge control agent.

The following substances control the toner to be positively charged.

Modified products such as nigrosine and fatty acid metal salts; quaternary ammonium salts such as tributylbenzylammonium-1-hydroxy-4-naphthosulfonate and tetrabutylammonium tetrafluoroborate;
And onium salts thereof such as phosphonium salts, which are analogs thereof, and lake pigments thereof, triphenylmethane dyes and these lake pigments (as the lake-forming agent, phosphotungstic acid, phosphomolybdic acid, phosphotungsten molybdic acid, tannin Acid, lauric acid, gallic acid, ferricyanide, ferrocyanide, etc.) metal salts of higher fatty acids; diorganotin oxides such as dibutyltin oxide, dioctyltin oxide, dicyclohexyltin oxide; dibutyltin borate, dioctyltin borate, dicyclohexyltin borate Diorganotin borates; guanidine compounds, imidazole compounds; These can be used alone or in combination of two or more. Among these, a triphenylmethane compound and a quaternary ammonium salt whose counter ion is not halogen are preferably used. The general formula (1)

[0101]

Embedded image Monomer of a monomer represented by: styrene described above,
Copolymers with polymerizable monomers such as acrylates and methacrylates can be used as positive charge control agents. In this case, these charge control agents also act as (all or part of) the binder resin.

In particular, compounds represented by the following general formula (2) are preferable in the constitution of the present invention.

[0103]

Embedded image

[Wherein R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R
⁶ represents a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group, which may be the same or different from each other. R ⁷ , R ⁸ and R ⁹ are
It represents a hydrogen atom, a halogen atom, an alkyl group or an alkoxy group, which may be the same or different from each other. A
^- is sulfate ion, nitrate ion, borate ion, phosphate ion, hydroxyl ion, organic sulfate ion, organic sulfonate ion, organic phosphate ion, carboxylate ion, organic borate ion, an anion such as tetrafluoroborate Show. The following substances control the toner to be negatively charged.

For example, organic metal complexes and chelate compounds are effective, and examples thereof include monoazo metal complexes, acetylacetone metal complexes, aromatic hydroxycarboxylic acids, and aromatic dicarboxylic acid-based 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.

Further, an azo metal complex represented by the following general formula (3) is preferred.

[0107]

Embedded image

In particular, the central metal is preferably Fe or Cr, the substituent is preferably a halogen, an alkyl group or an anilide group, and the counter ion is preferably hydrogen, an alkali metal, ammonium or aliphatic ammonium.
Also, a mixture of complex salts having different counter ions is preferably used.

Alternatively, a basic organic acid metal complex represented by the following general formula (4) also gives negative chargeability and can be used in the present invention.

[0110]

Embedded image

In particular, Fe, Cr, Si,
Zn and Al are preferred, and the substituent is preferably an alkyl group, an anilide group, an aryl group or a halogen, and the counter ion is preferably hydrogen, ammonium or aliphatic ammonium.

As a method for incorporating the charge control agent into the toner, there are a method of adding it inside the toner and a method of adding it externally. The use amount of these charge control agents is determined by the type of the binder resin, the presence or absence of other additives, the toner manufacturing method including the dispersion method, and is not limited to a specific one. Preferably, it is used in the range of 0.1 to 10 parts by weight, more preferably 0.1 to 5 parts by weight, based on 100 parts by weight of the binder resin.

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

The fine silica powder used in the present invention is BE
The specific surface area by nitrogen adsorption measured by the T method is 20 m ² / g
Those within the above range (particularly 30 to 400 m ² / g) give good results. It is preferable to use 0.01 to 8 parts by weight, preferably 0.1 to 5 parts by weight of silica fine powder with respect to 100 parts by weight of the toner.

The silica fine powder has a silicone varnish, various modified silicone varnishes, silicone oil, various modified silicone oils, a silane coupling agent, and a functional group, if necessary, for the purpose of hydrophobization, charge control, and the like. It is also preferable that the treatment is performed with a treating agent such as a silane coupling agent or another organosilicon compound, or in combination with various treating agents.

It is also preferable to add the following inorganic powder in order to improve developability and durability. Magnesium, zinc, aluminum, cerium, cobalt, iron, zirconium, chromium, manganese, strontium, tin,
Metal oxides such as antimony; composite metal oxides such as calcium titanate, magnesium titanate and strontium titanate; metal salts such as calcium carbonate, magnesium carbonate and aluminum carbonate; clay minerals such as kaolin;
Phosphate compounds such as apatite; silicon compounds such as silicon carbide and silicon nitride; and carbon powders such as carbon black and graphite. Among them, zinc oxide, aluminum oxide, cobalt oxide, manganese dioxide, strontium titanate, magnesium titanate and the like are preferable.

Further, the following lubricant powder can be added. Fluorine resins such as Teflon and polyvinylidene fluoride; fluorine compounds such as carbon fluoride; fatty acid metal salts such as zinc stearate; fatty acid derivatives such as fatty acids and fatty acid esters; molybdenum sulfide, amino acids and amino acid derivatives.

The toner of the present invention can be used as a two-component developer in combination with a carrier. When the toner is used in the two-component developing method, any known carrier can be used. Specifically, particles having an average particle size of 20 to 300 [mu] m, such as metals such as iron, nickel, cobalt, manganese, chromium, and rare earths, and their alloys and oxides, whose surface is oxidized or not oxidized, are used.

Further, those obtained by attaching or coating a substance such as a styrene resin, an acrylic resin, a silicone resin, a fluorine resin, or a polyester resin on the surface of the carrier particles are preferably used.

The magnetic material used in the present invention is lithium,
Beryllium, boron, magnesium, aluminum, silicon, phosphorus, germanium, titanium, zirconium,
It is a magnetic iron oxide containing at least one element selected from tin and zinc. These elements may be taken into the iron oxide crystal lattice, may be taken into the iron oxide as an oxide, or may exist as oxides or hydroxides on the surface.

These elements can be incorporated into the particles by adjusting the pH by mixing the salts of the respective elements during the formation of the magnetic material. After the magnetic particles are formed, the pH can be adjusted, or a salt of each element is added to adjust the pH, whereby the particles can be precipitated on the particle surface.

The magnetic material containing these elements is well compatible with the binder resin and has very good dispersibility. Further, this good dispersibility can improve the dispersibility of the wax used in the present invention, and the effect of the wax of the present invention can be sufficiently exhibited. That is, the magnetic material acts as a dispersion medium, and the dispersion of the wax is assisted by the good dispersibility of the magnetic material, and the dispersibility of the wax is improved.

These magnetic materials have a uniform particle size distribution.
In combination with the dispersibility in the binder resin, the chargeability of the toner can be stabilized. In recent years, the toner particle diameter has been reduced, and even when the average particle diameter is 10 μm or less, charging uniformity is promoted, toner cohesion is reduced, image density is improved, and fog is improved. Developability is improved. On the other hand, as the particle size of the toner decreases, wax is likely to be released. However, the toner of the present invention is excellent in charging uniformity, so that even if some free wax is present, blotching or the like is unlikely to occur.

The content of these elements is preferably 0.05 to 10% by weight based on the iron element of the magnetic iron oxide. It is more preferably 0.1 to 7% by weight, particularly preferably 0.2 to 5% by weight. If it is less than 0.05% by weight, the effect of containing these elements cannot be obtained, and good dispersibility and uniform charging cannot be obtained. If the content is more than 10% by weight, the release of electric charge increases, causing insufficient charging,
The image density may be low or fog may increase.

These magnetic materials preferably have an average particle size of 1.0 μm or less, more preferably 0.1 to 0.5 μm. Those having a BET specific surface area of ² to 40 mm ² / g are used. The shape is not particularly limited, and an arbitrary shape is used. As magnetic properties, a magnetic field of 795.8 kA /
m, the saturation magnetization is 10 to 200 Am ² / kg, the residual magnetization is 1 to 100 Am ² / kg, and the coercive force is 1 to 30 kA / m.
Is used. These magnetic materials are binder resin 1
It is used in an amount of 20 to 200 parts by weight based on 00 parts by weight.

The amount of the element in the magnetic iron oxide of the present invention is determined by the fluorescent X
The measurement was performed by performing X-ray fluorescence analysis using a line analyzer SYSTEM3080 (manufactured by Rigaku Denki Kogyo Co., Ltd.) in accordance with JIS K0119 X-ray fluorescence analysis rules. The number average diameter can be determined by measuring a photograph enlarged and taken with a transmission electron microscope using a digitizer or the like.

As the colorant that can be used in the toner of the present invention, any suitable pigment or dye can be used. As a colorant of the toner, for example, carbon black as a pigment,
Examples include aniline black, acetylene black, naphthol yellow, hansa yellow, rhodamine lake, alizarin lake, bengalara, phthalocyanine blue, and indanthrene blue. These are used in an amount necessary and sufficient to maintain the optical density of the fixed image, and 0.1 to 20 parts by weight, preferably 0.2 to 10 parts by weight, per 100 parts by weight of the resin.
Good addition amount by weight. A dye is further used for the same purpose. For example, there are azo dyes, anthraquinone dyes, xanthene dyes, and methine dyes.
0.1 to 20 parts by weight, preferably 0.3 to parts by weight
The addition amount of 10 to 10 parts by weight is good.

To prepare the toner for developing an electrostatic image according to the present invention, a binder resin, a wax, a metal salt or a metal complex, a pigment or dye as a colorant, a magnetic substance, a charge control agent if necessary, While the other additives, etc. were thoroughly mixed by a mixer such as a Henschel mixer, a ball mill, and then melt-kneaded using a heat kneader such as a heating roll, a kneader, or an extruder to make the resins compatible with each other. A toner according to the present invention can be obtained by dispersing or dissolving a metal compound, a pigment, a dye, and a magnetic substance, and solidifying by cooling, followed by pulverization and classification.

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

The particle size distribution can be measured by various methods. In the present invention, the particle size distribution was measured using a Coulter counter multisizer.

That is, a Coulter counter Multisizer II (manufactured by Coulter) was used as a measuring device, and an interface (manufactured by Nikkaki) for outputting the number distribution and volume distribution and a personal computer were connected.
The electrolyte is 1% N using special grade or first grade sodium chloride.
An aqueous aCl solution is prepared. As a measuring method, a surfactant, preferably an alkylbenzene sulfonate, of 0.1 to 5 m is used as a dispersant in 100 to 150 ml of the electrolytic aqueous solution.
1 to 2 mg of the measurement sample. The electrolyte in which the sample was suspended was subjected to dispersion treatment for about 1 to 3 minutes using an ultrasonic disperser.
When the toner particle size is measured as an aperture by the I-type, the measurement is performed using a 100 μm aperture.
The volume distribution and the number distribution were calculated by measuring the volume and the number of the toner. Then, the weight-based weight average diameter according to the present invention is determined from the volume distribution.

[0132]

The present invention will be described below with reference to specific examples.

First, the wax used in the present invention will be described.

The high molecular weight polyethylene was thermally decomposed to obtain low molecular weight wax A and further low molecular weight wax E. From these waxes, waxes B, C and D having sharp molecular weight distributions were obtained by vacuum distillation. Also, radical polymerization of ethylene was performed under high pressure to obtain wax F having a higher molecular weight than wax A, and waxes G, H, and I having a sharp molecular weight distribution by fractional crystallization were obtained. Table 1 shows the physical properties of these waxes.

Next, the magnetic material used in the present invention will be described.

Magnetite particles were produced while adding a salt of an element present therein at the time of magnetite production to adjust the pH, and magnetic materials 1 to 5 were obtained. The magnetic body 1 contains silicate,
The magnetic material 2 was prepared by adding silicate and aluminum salt, the magnetic material 3 by adding phosphate, and the magnetic material 4 by adding magnesium salt to produce magnetite particles. The magnetic material 5 was prepared by adding a zinc salt to produce magnetite particles, adding silicate to adjust the pH, and precipitating silica on the surface of the magnetite particles to obtain a magnetic material. The magnetic material 6 was prepared by adding phosphate to generate magnetite particles, then adding silicate to adjust the pH, and precipitating silica on the surface of the magnetite particles to obtain a magnetic material. In particular, magnetite particles were generated without adding a salt, and a magnetic material 8 was obtained. After the magnetic material 8 was formed, the pH was adjusted by adding a zirconium salt, and zirconia was precipitated on the surface of the magnetite particles to obtain a magnetic material 7. Table 2 shows the physical properties of these magnetic materials.

Next, the binder resin used in the present invention will be described.

(Resin Synthesis Example 1) 200 parts by weight of xylene was charged into a four-necked flask equipped with a nitrogen gas inlet tube, a condenser, a stirrer, and a thermometer, and the mixture was stirred and heated at 140 ° C. under a nitrogen gas stream. , 84 parts by weight of styrene, 16 parts by weight of n-butyl acrylate, and 2 parts by weight of di-t-butyl peroxide (DTBP) as an initiator were dropped over 4 hours using a continuous dropping apparatus to carry out polymerization. Thereafter, the solvent was removed to obtain a polymer A. When the molecular weight distribution of the polymer A was measured by GPC, it had a maximum value at a molecular weight of 0.880, and Mw / Mn was 2.32.

(Resin Synthesis Example 2) 80 parts by weight of styrene was added to 300 parts by weight of a 0.1% aqueous solution of polyvinyl alcohol.
20 parts by weight of n-butyl acrylate, 2,2
A mixture of 0.2 parts by weight of 2-bis (4,4-di-t-butylperoxycyclohexyl) propane was charged into the polymerization apparatus of Resin Synthesis Example 1, and polymerization was performed at a polymerization temperature of 90 ° C. for 24 hours. Thereafter, the mixture is cooled, washed with water, dried, and polymer B
I got When the molecular weight distribution of the polymer B was measured by GPC, it had a maximum value at a molecular weight of 720,000, and Mw / Mn was 3.
67.

The polymer A and the polymer B were mixed in a weight ratio of 75:25 to obtain a binder resin 1 of a styrene-acrylate copolymer. (Resin Synthesis Example 3) 300 parts by weight of a 0.1% aqueous solution of polyvinyl alcohol, 70 parts by weight of styrene, 30 parts by weight of n-butyl acrylate, 0.2 parts by weight of divinylbenzene, and 2,2′-azobis as an initiator A mixture of 1 part by weight of isobutyronitrile was charged into the polymerization apparatus of Resin Synthesis Example 1 and polymerized at a polymerization temperature of 90 ° C. for 10 hours. Thereafter, the resultant was cooled, washed with water, and dried to obtain a binder resin 2. The molecular weight distribution of the binder resin 2 was measured by GPC. As a result, the molecular weight had a maximum value of 124,000, Mw / Mn was 10.4, and the gel content was 20% by weight.

<Example 1> Binder resin 1 100 parts by weight Magnetic substance 1 80 parts by weight Triphenylmethane compound 2 parts by weight Wax B 4 parts by weight Wax G 2 parts by weight

After the above materials were premixed, they were kneaded with a twin screw extruder set at 130 ° C. After cooling the obtained kneaded material and coarsely pulverizing with a cutter mill, finely pulverizing using a fine pulverizer using a jet stream, using a multi-divided classifier using the Coanda effect to obtain the finely pulverized powder. And classified to obtain a toner 1 having a weight average particle size of 6.80 μm. 100 parts by weight of this toner and 0.9 part by weight of positively charged hydrophobic colloidal silica fine powder were mixed (externally added), and a toner having colloidal silica fine powder on the surface of toner particles was used as a developer. Table 3 shows the physical properties when the waxes B and G were mixed at a ratio of 2: 1. Table 4 shows the physical properties of the toner. Further, the toner was subjected to a fixing property test, an offset resistance test, a blocking resistance test, and an image output test.

As a result, good low-temperature fixability and low
Good offset resistance at high temperatures was obtained. There were no problems in blocking resistance, image density stability, and blotching. Table 5 shows the results.

The test method for evaluating the toner is as follows.

Low Temperature Fixability and Offset Resistance Test The above-mentioned developer was charged into a modified machine of an electrophotographic copying machine NP4080 (manufactured by Canon Inc.) from which the fixing device was removed to obtain an unfixed image. On the other hand, the fixing device removed from the NP4080 was remodeled to be a temperature-variable heat roller external fixing device,
Using this, a fixing property test and an offset resistance test of an unfixed image were performed.

The nip of the external fixing device was set to 5.0 mm, the process speed was set to 150 mm / s, and
The temperature is controlled every 5 ° C. in a temperature range of 0 ° C., and an unfixed image is fixed at each temperature.
The paper was rubbed reciprocally five times with a silbon paper with a weight of m ² , and the fixing temperature at which the image density reduction rate before and after the rubbing was 10% or less was defined as the fixing start temperature.

For the offset, the temperature at which the image was not stained by the unfixed toner visually was set as the low-temperature offset-free starting point, the temperature was raised, and the maximum temperature without offset was set as the high-temperature offset-free end point.

Image Output Test (Image Characteristics) Using an electrophotographic copying machine NP4080 (manufactured by Canon Inc.), 5,000 images were continuously output on an A4 size transfer paper using an A4 size image area ratio of 6%. The image density was evaluated from the copied image. In addition, blotting was evaluated based on the state of the toner coat on the toner carrier and the copy image during image output.

(Image Density Stability) 濃度 There is no density unevenness on the image and the density is stable and good. ○ There is no density unevenness on the image, but there is a slight decrease in density. △ Density unevenness on the image was slight, and density was reduced. C: Density unevenness and density decrease on the image are remarkable.

(Blotch) ら れ Not observed at all. ○ Slightly visible on the toner carrier, but not visible on the image. C: Appears on the toner carrier and appears faintly on the image. × Appears markedly on the image.

Blocking Resistance Test About 10 g of the developer was placed in a 100 cc polycup, and
After leaving it at 3 ° C. for 3 days, it was visually evaluated.

◎ No aggregate was observed. ○ Aggregates can be seen but easily collapse. △ Aggregates are seen, but collapse when shaken. X: Aggregates can be grasped and do not collapse easily.

<Example 2> The procedure of Example 1 was repeated except that 4 parts by weight of wax B and 2 parts by weight of wax G were melt-mixed with stirring, cooled, solidified, and ground, and the magnetic substance 2 was used. A toner 2 was prepared and evaluated in the same manner as in Example 1. The results are shown in Table 5, and the physical properties of the toner are shown in Table 4.

<Example 3> In Example 1, 100 parts by weight of binder resin 1 was used instead of binder resin 1 and wax.
Is dissolved in a xylene solvent, the temperature of the resin solution is increased, and 4 parts by weight of wax B and 2 parts by weight of wax G are added and mixed with stirring, and the solvent containing the dried binder resin and the magnetic substance 3 are removed. Example 1 except that
In the same manner as in the above, a toner 3 was prepared and evaluated. The results are shown in Table 5, and the physical properties of the toner are shown in Table 4.

Example 4 Toner 4 was prepared and evaluated in the same manner as in Example 1 except that 4 parts by weight of wax C, 2 parts by weight of wax H, and magnetic substance 4 were used. The results are shown in Table 5, the physical properties when waxes C and H were mixed at a ratio of 2: 1 are shown in Table 3, and the physical properties of the toner are shown in Table 4.

Example 5 Toner 5 was prepared and evaluated in the same manner as in Example 3, except that 4 parts by weight of wax C, 2 parts by weight of wax H, and magnetic substance 5 were used. The results are shown in Table 5, and the physical properties of the toner are shown in Table 4.

Example 6 Toner 6 was prepared and evaluated in the same manner as in Example 1 except that 4 parts by weight of wax D, 2 parts by weight of wax I, and magnetic substance 6 were used. The results are shown in Table 5, the physical properties when waxes D and I were mixed at a ratio of 2: 1 are shown in Table 3, and the physical properties of the toner are shown in Table 4.

<Example 7> Toner 7 was prepared and evaluated in the same manner as in Example 3, except that 4 parts by weight of wax D, 2 parts by weight of wax I, and magnetic substance 7 were used. The results are shown in Table 4, and the physical properties of the toner are shown in Table 3.

Example 8 100 parts by weight of binder resin 2 80 parts by weight of magnetic substance 1 2 parts by weight of triphenylmethane compound 4 parts by weight of wax D 2 parts by weight of wax I

Using the above materials, a toner 8 was prepared and evaluated in the same manner as in Example 1. The results are shown in Table 5, and the physical properties of the toner are shown in Table 4.

<Comparative Example 1> Toner 9 was prepared in the same manner as in Example 8 except that magnetic substance 8 was used instead of magnetic substance 1.
Was obtained and evaluated. The results are shown in Table 5, and the physical properties of the toner are shown in Table 4. The results were slightly inferior in developability, such as image density stability and blotches.

<Comparative Example 2> A toner 10 was obtained and evaluated in the same manner as in Example 8, except that 4 parts by weight of the wax B was used instead of the waxes D and I in the comparative example 1. The results are shown in Table 5, and the physical properties of the toner are shown in Table 4. The result was slightly inferior in offset resistance.

<Comparative Example 3> Toner 11 was obtained and evaluated in the same manner as in Example 8, except that wax G was used in place of waxes D and I in an amount of 4 parts by weight. The results are shown in Table 5, and the physical properties of the toner are shown in Table 4. The result was slightly inferior in low-temperature fixability.

<Comparative Example 4> A toner 12 was obtained and evaluated in the same manner as in Example 8 except that in place of waxes D and I, 4 parts by weight of wax E and 2 parts by weight of F were used. The results are shown in Table 5, and the physical properties of the toner are shown in Table 4. The results were slightly inferior to blocking resistance and blotching.

Comparative Example 5 A toner 13 was obtained and evaluated in the same manner as in Example 8, except that 4 parts by weight of the wax A was used instead of the waxes D and I in the comparative example 1. The results are shown in Table 5, and the physical properties of the toner are shown in Table 4. The result was slightly inferior in low-temperature fixability.

[0166]

[Table 1]

[0167]

[Table 2]

[0168]

[Table 3]

[0169]

[Table 4]

[0170]

[Table 5]

[0171]

According to the present invention, by using the above-mentioned wax, it is possible to provide a toner having a wide fixing temperature range and excellent low-temperature fixing property and offset resistance.

Further, the present invention can provide a toner which has excellent blocking resistance and does not deteriorate developability.

Furthermore, the present invention can provide a toner free from blotching.

[Brief description of the drawings]

FIG. 1 is a graph showing a chromatogram of GPC when waxes B and G in toner 1 (Example 1) of the present invention are mixed at a ratio of 2: 1.

FIG. 2 is a graph showing a chromatogram of GPC when the waxes D and I in the toner 6 of the present invention (Example 6) are mixed at a ratio of 2: 1.

FIG. 3 is a diagram showing a GPC chromatogram of Toner 1 (Example 1) of the present invention.

Claims (5)

[Claims] 1. A toner for developing an electrostatic image containing at least a binder resin, a wax and a magnetic material, wherein the wax has a molecular weight of 300 to 800 in a chromatogram measured by GPC (gel permeation chromatography). At least one local maximum or shoulder in each of the 800 to 7,000 regions, wherein the magnetic material is lithium, beryllium,
A toner for developing an electrostatic image, comprising magnetic iron oxide containing at least one element selected from the group consisting of boron, magnesium, aluminum, silicon, phosphorus, germanium, titanium, zirconium, tin, and zinc. 2. The chromatogram measured by GPC of the wax, wherein the wax has at least one maximum value or shoulder in each of a region having a molecular weight of 350 to 750 and a region having a molecular weight of 900 to 5,000. The toner for developing an electrostatic image according to claim 1. 3. The chromatogram of the toner measured by GPC has at least one maximum value or shoulder in each of a region having a molecular weight of 300 to 3,000 and a region having a molecular weight of 3,500 to 50,000. 3. The electrostatic image developing toner according to claim 1, wherein the toner has at least one maximum value or shoulder in a region having a molecular weight of 100,000 or more. 4. The binder resin according to claim 1, wherein the binder resin is dissolved in a solvent, the wax is added, mixed, desolvated, and dried. 3. The toner for developing an electrostatic image according to item 1. 5. A chromatogram measured by GPC of the wax, wherein the wax has at least one maximum value or shoulder in each of a region having a molecular weight of 300 to 800 and a region having a molecular weight of 800 to 7,000, and has a low molecular weight. Between the maximum peak height (H ₁ ) in the side region, the maximum peak height (H ₃ ) in the high molecular weight region, and the minimum height (H ₂ ) between both peaks, H ₁ > 5. The electrostatic image developing toner according to claim 1, wherein a relationship of H ₃ , H ₃ ≧ H ₂ , and H ₁ > H ₂ is satisfied.