JP2001154405A - Electrostatic charge image developing toner, method for producing same, electrostatic charge image developer and image forming method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce an electrostatic charge image developing toner having good cleanability, less liable to fuse on a carrier and a developing sleeve and capable of attaining high image quality and to provide an electrostatic charge image developer and an electrophotographic image forming method using the toner. SOLUTION: At least resin particles and colorant particles are subjected to salting-out and fusion from a dispersion containing the resin particles and the colorant particles to obtain the objective electrostatic charge image developing toner. The molecular weight distribution of the resin component of the toner has peaks or shoulders in at least the ranges of 1,500-20,000 and 50,000-500,000, the Mw to Mn ratio on the low molecular weight side is 1.2-4.0 and that on the high molecular weight side is 2.0-3.0.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toner for developing an electrostatic image for visualizing an electrostatic latent image in an image forming method such as an electrophotographic method, an electrostatic printing method and an electrostatic recording method. More particularly, the present invention relates to an electrostatic image developer using the toner and an image forming method using the developer.

[0002]

2. Description of the Related Art As a toner for copying machines and printers utilizing electrostatic latent image development, a toner obtained by a pulverizing method is currently the mainstream. When the pulverized toner is improved, fine powder of the toner is generated at the time of pulverization, and it is difficult to remove the fine powder by classification, and the fine powder toner finally remains in the toner. When a toner containing such a fine powder toner is used, since the fine powder toner has a strong adhesive property, it is difficult to transfer from the photoreceptor to the transfer member after development, and the fine powder toner is liable to cause a cleaning failure. Fine powder toner is easily fused to a carrier or the like, causing a so-called spent phenomenon, further causing a fusion to a developing sleeve, etc., and as a result, the charge imparting ability of the carrier and the like is reduced,
There has been a difficult problem to be solved, such as a decrease in the charge amount of the toner and an increase in the charge amount distribution (such as an increase in the amount of the weakly chargeable toner), and it is easy to eventually cause fogging and the like. or,
In recent years, there has been an increasing demand for higher image quality from the market, and there has been a demand for a toner having a sharp particle size distribution and a small particle size. However, it is extremely difficult to manufacture a pulverized toner capable of satisfying this problem. It is.

[0003] As a method of solving the above problems,
In recent years, there has been an increasing demand for higher image quality from the market, and as a method of producing small-sized particles having a sharp particle size distribution at low cost, polymerization toners using emulsion polymerization, suspension polymerization, dispersion polymerization, etc. Manufacturing methods have been actively proposed (for example,
As a method for producing a toner by an emulsion polymerization method, Japanese Patent Application Laid-Open
186253, JP-A-6-329947, JP-A-9-96919, etc.).

[0004] Among the above-mentioned polymerized toners, a so-called emulsion-association type polymerized toner manufacturing method of using an emulsion polymerized particle, forming an aggregate of the emulsion polymerized particle and a colorant, and then fusing the same, is described in US Pat. Due to the characteristics of (1), since non-spherical particles can be produced, there is an advantage that a small particle size toner having a sharp particle size distribution with excellent cleaning properties can be produced as compared with a suspension polymerization toner having a spherical toner shape. Have.

[0005] However, in the emulsion-association type polymerization toner,
Because the toner particles are composed of resin particles and colored particles,
Colored particles may be unevenly distributed inside the toner. In a toner in which such particles are unevenly distributed, when shear stress or the like is applied to the toner, the toner is crushed and fine particles are generated.

As a result, there is a problem that the fine particles adhere to a charge-imparting agent such as a carrier, thereby lowering the chargeability, and a problem that fine particles adhere to a photoreceptor to cause poor cleaning.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a toner for developing an electrostatic image, which has good cleaning properties, does not easily fuse to a carrier or a developing sleeve, and can achieve high image quality. And an electrostatic image developer, and an electrophotographic image forming method using the toner.

[0008]

The above object is achieved by the following constitution.

1. Salting out at least the resin particles and the colorant particles from a dispersion solution containing the resin particles and the colorant particles;
In the fused toner, the molecular weight distribution of the resin component measured by GPC of the toner is at least 1,500.
20,000 and 50,000-500,000, and the molecular weight distribution (ML) derived from the peak or shoulder on the lower molecular weight side is Mw / M.
n = 1.2 to 4.0, and the molecular weight distribution (MH) derived from one peak or shoulder on the high molecular weight side is M
A toner for developing an electrostatic image, wherein w / Mn is 2.0 to 30.0.

[0010] 2. 2. The electrostatic image developing toner according to claim 1, wherein the molecular weight distribution ML on the low molecular weight side and the molecular weight distribution MH on the high molecular weight side satisfy MH ≧ ML.

3. In a method for producing a toner by salting out / fusing the resin particles and the colorant particles from a dispersion solution containing the resin particles and the colorant particles, two or more resin particles are used as the resin particles, One of them has a peak or shoulder at 1,500 to 20,000 in the molecular weight distribution measured by GPC, and Mw / Mn = 1.2.
~ 4.0 low molecular weight resin particles, the other one being 5
A method for producing a toner for developing an electrostatic image, comprising high molecular weight resin particles having a peak or shoulder at 000 to 500,000 and having Mw / Mn = 2.0 to 30.0.

4. Molecular weight distribution M of the low molecular weight resin particles
The w / Mn and ML _P, when the molecular weight distribution Mw / Mn of the high molecular weight resin particles have a MH _P, the third manufacturing method of the electrostatic image developing toner, wherein the a MH _P ≧ ML _P .

5. 3. An electrostatic image developer comprising: the electrostatic image developing toner according to 1 or 2; and a carrier in which magnetic particles are coated with a resin.

6. Using an electrophotographic photosensitive member, charging, exposure,
An image forming method for transferring a toner image produced through a development process to a recording material and cleaning the toner remaining on the photoreceptor, the developer comprising the electrostatic image developing toner described in 1 or 2 above An image forming method, wherein the image is formed using

The present invention will be described in detail below. The toner for developing an electrostatic image of the present invention is a toner obtained by salting out / fusing at least the resin particles and the colorant particles from a dispersion solution containing the resin particles and the colorant particles. The resin particles before the salting-out / fusion are 50 to 2000 n in weight average particle diameter.
m is preferred.

On the other hand, the colorant particles include organic pigments,
Inorganic pigments and the like can be used, but in order to ensure dispersion stability in the dispersion solution, the weight average particle size of these colorant particles is preferably 5 to 500 nm.

The toner for developing an electrostatic image of the present invention is obtained by salting out and fusing at least the resin particles and the colorant particles. This salting-out, and fusion, the salting-out agent is added to water in which the resin particles and the colorant particles are dispersed, an organic solvent that dissolves infinitely as necessary is added, and then salting out is performed by heating. At the same time, the fusion is advanced to adjust the toner particles. In this method, unlike the method of fusing after forming the aggregated primary particles of the resin particles and the colorant particles, the method is capable of fusing without passing through an intermediate stage and adjusting the toner particles. The uniformity of the toner particles formed by salting out and fusing is not impaired, the distribution of the colorant particles in the toner becomes uniform, and as a result, a toner having a uniform chargeability can be stably obtained. You can do it.

The resin component of the toner for developing an electrostatic image of the present invention has a molecular weight distribution measured by GPC of at least 1,5.
It has peaks or shoulders at 00 to 20,000 and 50,000 to 500,000, and the molecular weight distribution (ML) derived from the low molecular weight side peak or shoulder is Mw.
/Mn=1.2 to 4.0 and molecular weight distribution (MH) derived from one peak or shoulder on the high molecular weight side
Is characterized by Mw / Mn = 2.0 to 30.0. In order to achieve such a resin component, a plurality of resin particles having different molecular weight distributions are mixed with the resin particles, and The most preferred method is to prepare a toner by the above-described method of salting out and fusing. That is, by using two or more kinds of resin particles having a uniform molecular weight distribution, the toner for developing an electrostatic charge image having a molecular weight distribution of the present invention can be achieved after the colorant particles are uniformly dispersed in the toner as described above. Can be. Here, Mw represents a weight average molecular weight, and Mn represents a number average molecular weight.

The above molecular weight distribution indicates a molecular weight distribution in terms of styrene measured by GPC. That is, the method of measuring the molecular weight of a resin by GPC is a measurement by GPC (gel permeation chromatography) using THF as a solvent. That is, 1 cc of THF is added to 0.5 to 5 mg, more specifically, 1 mg of a measurement sample, and the mixture is stirred at room temperature using a magnetic stirrer or the like to be sufficiently dissolved. Then, after treating with a membrane filter having a pore size of 0.45 to 0.50 μm, the mixture is injected into GPC. The GPC measurement conditions are as follows: stabilize the column at 40 ° C., flow THF at a flow rate of 1 cc per minute, and inject about 100 μl of a 1 mg / cc concentration sample for measurement. The column is preferably used in combination with a commercially available polystyrene gel column. For example, Showa Denko Sho
dex GPC KF-801,802,803,80
4,805,806,807 and TSKgel G1000H, G2000H, G3000 manufactured by Tosoh Corporation
H, G4000H, G5000H, G6000H, G7
000H, TSK guard column and the like. Further, a refractive index detector (IR detector) or a UV detector may be used as the detector. In measuring the molecular weight of a sample, the molecular weight distribution of the sample is calculated using a calibration curve created using monodispersed polystyrene standard particles. It is preferable to use about 10 polystyrenes for preparing a calibration curve.

By uniformly dispersing the pigment in the toner, the charge distribution of the toner becomes sharp, and the toner is less likely to be crushed even when shearing stress is applied to the toner. In addition, the toner has a stable chargeability, and has an effect of improving characteristics such that poor cleaning hardly occurs.

Further, by designing the molecular weight distribution in the toner within the above range, the high molecular weight component is oriented near the surface when the resin particles are fused, so that the strength of the toner itself is increased and the toner is crushed. An effect of improving characteristics such as hardly occurring is obtained.

Further, the molecular weight distribution (Mw
/ Mn) is ML, the molecular weight distribution (Mw / Mn) derived from one peak or shoulder on the high molecular weight side is MH,
When MH ≧ ML, the high molecular weight component is oriented in the vicinity of the surface, and the tendency of the toner itself to increase becomes stronger, so that the property that the toner is hardly crushed is remarkably improved.

Other means for controlling the molecular weight distribution of the resin particles include conditions for preparing the resin particles, ie, the amount of the chain transfer agent added, the amount of the water-soluble radical polymerization initiator added, and the temperature control of the polymerization reaction. Is to adjust.

Each technical item will be described below in detail. The resin particles used in the production of the toner of the present invention preferably have a weight average particle size of 50 to 2,000 nm, and the most preferred production method of these resin particles is an emulsion polymerization method. Less than,
An example of a material and a production method of resin particles by an emulsion polymerization method will be described. Incidentally, the emulsion polymerization method is a method in which the following monomers are added to water containing a surfactant, and the mixture is emulsified and then polymerized.

<< Materials >> [Monomer] As the polymerizable monomer, a radical polymerizable monomer is an essential component, and a crosslinking agent can be used if necessary. Further, it is preferable to contain at least one radical polymerizable monomer having an acidic group or a radical polymerizable monomer having a basic group described below. (1) Radical polymerizable monomer The radical polymerizable monomer component is not particularly limited, and a conventionally known radical polymerizable monomer can be used. Also, to satisfy the required characteristics,
Species or a combination of two or more can be used.

Specifically, aromatic vinyl monomers, (meth) acrylate monomers, vinyl ester monomers, vinyl ether monomers, monoolefin monomers, diolefin monomers Monomers, halogenated olefin monomers and the like can be used.

As the aromatic vinyl monomer, for example,
Styrene, o-methylstyrene, m-methylstyrene,
p-methylstyrene, p-methoxystyrene, p-phenylstyrene, p-chlorostyrene, p-ethylstyrene, p-n-butylstyrene, p-tert-butylstyrene, p-n-hexylstyrene, p-n- Styrene-based monomers such as octylstyrene, pn-nonylstyrene, pn-decylstyrene, pn-dodecylstyrene, 2,4-dimethylstyrene, and 3,4-dichlorostyrene, and derivatives thereof. .

Examples of the (meth) acrylate monomers include methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, phenyl acrylate, methyl methacrylate, and ethyl methacrylate. Butyl methacrylate, hexyl methacrylate, 2-ethylhexyl methacrylate, ethyl β-hydroxyacrylate, propyl γ-aminoacrylate, stearyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, and the like.

Examples of the vinyl ester monomer include vinyl acetate, vinyl propionate, vinyl benzoate and the like.

Examples of the vinyl ether monomer include vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether, vinyl phenyl ether and the like.

Examples of the monoolefin-based monomer include ethylene, propylene, isobutylene, 1-butene, 1-pentene and 4-methyl-1-pentene.

Examples of the diolefin-based monomer include butadiene, isoprene, chloroprene and the like.

As the halogenated olefin-based monomer,
Vinyl chloride, vinylidene chloride, vinyl bromide and the like. (2) Crosslinking Agent As the crosslinking agent, a radical polymerizable crosslinking agent may be added to improve the properties of the toner. Examples of the radical polymerizable crosslinking agent include divinylbenzene, divinylnaphthalene,
Examples thereof include those having two or more unsaturated bonds such as divinyl ether, diethylene glycol methacrylate, ethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, and diallyl phthalate. (3) Radical polymerizable monomer having an acidic group or radical polymerizable monomer having a basic group As the radical polymerizable monomer having an acidic group or the radical polymerizable monomer having a basic group, For example, amine compounds such as carboxyl group-containing monomers, sulfonic acid group-containing monomers, primary amines, secondary amines, tertiary amines, and quaternary ammonium salts can be used.

As the radical polymerizable monomer having an acidic group, acrylic acid, methacrylic acid, fumaric acid, maleic acid, itaconic acid, cinnamic acid, monobutyl maleate, And monooctyl maleate.

Examples of the sulfonic acid group-containing monomer include styrene sulfonic acid, allyl sulfosuccinic acid, octyl allyl sulfosuccinate and the like.

These may have a structure of an alkali metal salt such as sodium or potassium or an alkaline earth metal salt such as calcium.

Examples of the radical polymerizable monomer having a basic group include amine compounds, such as dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, diethylaminoethyl acrylate, diethylaminoethyl methacrylate, and the above four compounds. Quaternary ammonium salt, 3-dimethylaminophenyl acrylate, 2-hydroxy-3-methacryloxypropyltrimethylammonium salt, acrylamide, N-
Butylacrylamide, N, N-dibutylacrylamide, piperidylacrylamide, methacrylamide, N
-Butylmethacrylamide, N-octadecylacrylamide; vinylpyridine, vinylpyrrolidone; vinyl N
-Methylpyridinium chloride, vinyl N-ethylpyridinium chloride, N, N-diallylmethylammonium chloride, N, N-diallylethylammonium chloride and the like.

As the radical polymerizable monomer used in the present invention, a radical polymerizable monomer having an acidic group or a radical polymerizable monomer having a basic group is used in an amount of 0.1 to 15% of the whole monomer. The radical polymerizable cross-linking agent is preferably used in an amount of 0.1 to 10% by mass with respect to the total radical polymerizable monomer, although it depends on its properties.

[Chain transfer agent] For the purpose of adjusting the molecular weight, a commonly used chain transfer agent can be used.

The chain transfer agent is not particularly restricted but includes, for example, mercaptans such as octyl mercaptan, dodecyl mercaptan and tert-dodecyl mercaptan, and styrene dimers.

[Polymerization Initiator] The radical polymerization initiator used in the present invention can be appropriately used as long as it is water-soluble.
For example, persulfates (potassium persulfate, ammonium persulfate, etc.), azo compounds (4,4'-azobis-4-cyanovaleric acid and its salts, 2,2'-azobis (2-amidinopropane) salts, etc.), peroxides And the like.

Further, the above radical polymerization initiator can be used as a redox initiator in combination with a reducing agent, if necessary. By using a redox-based initiator, the polymerization activity is increased, the polymerization temperature can be reduced, and a further reduction in the polymerization time can be expected.

As the polymerization temperature, any temperature may be selected as long as it is equal to or higher than the minimum radical generation temperature of the polymerization initiator, but for example, a range of 50 ° C. to 90 ° C. is used. However, it is also possible to polymerize at room temperature or higher by using a combination of a polymerization initiator started at room temperature, for example, a hydrogen peroxide-reducing agent (such as ascorbic acid).

[Surfactant] In order to carry out emulsion polymerization using the above-mentioned radically polymerizable monomer, it is necessary to carry out emulsion polymerization using a surfactant. The surfactant that can be used at this time is not particularly limited, but the following ionic surfactants can be mentioned as preferred examples.

Examples of the ionic surfactant include sulfonates (sodium dodecylbenzenesulfonate, sodium arylalkyl polyethersulfonate, 3,3-
Sodium disulfonediphenylurea-4,4-diazo-bis-amino-8-naphthol-6-sulfonate, ortho-carboxybenzene-azo-dimethylaniline,
2,2,5,5-tetramethyl-triphenylmethane-
Sodium 4,4-diazo-bis-β-naphthol-6-sulfonate), sulfate (sodium dodecyl sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate, etc.), fatty acid salt (sodium oleate, laurin) Sodium acid,
Sodium caprate, sodium caprylate, sodium caproate, potassium stearate, calcium oleate, etc.).

Further, nonionic surfactants can also be used. Specifically, polyethylene oxide, polypropylene oxide, a combination of polypropylene oxide and polyethylene oxide, an ester of polyethylene glycol and higher fatty acid, an alkylphenol polyethylene oxide, an ester of higher fatty acid and polyethylene glycol, an ester of higher fatty acid and polypropylene oxide, a sorbitan ester Etc. can be given.

In the present invention, these are mainly used as emulsifiers at the time of emulsion polymerization, but they may be used for other steps or purpose.

[Colorant] Examples of the colorant include inorganic pigments and organic pigments.

Conventionally known inorganic pigments can be used. Although any pigment can be used, specific inorganic pigments are exemplified below.

Examples of black pigments include furnace black, channel black, acetylene black,
Carbon black such as thermal black and lamp black, and magnetic powder such as magnetite and ferrite are also used.

These inorganic pigments can be used alone or in combination of two or more as desired. The amount of the pigment to be added is 2 to 20 parts by mass, preferably 3 to 15 parts by mass, based on the polymer.

When used as a magnetic toner, the above-mentioned magnetite can be added. In this case, from the viewpoint of imparting predetermined magnetic characteristics, 20 to 60
It is preferable to add by mass%.

As the organic pigment, conventionally known organic pigments can be used. Although any pigment can be used, specific organic pigments are exemplified below.

As pigments for magenta or red,
C. I. Pigment Red 2, C.I. I. Pigment Red 3, C.I. I. Pigment Red 5, C.I. I. Pigment Red 6, C.I. I. Pigment Red 7, C.I. I. Pigment Red 15, C.I. I. Pigment Red 16,
C. I. Pigment Red 48: 1, C.I. I. Pigment Red 53: 1, C.I. I. Pigment Red 57:
1, C.I. I. Pigment Red 122, C.I. I. Pigment Red 123, C.I. I. Pigment Red 139,
C. I. Pigment red 144, C.I. I. Pigment Red 149, C.I. I. Pigment Red 166, C.I.
I. Pigment Red 177, C.I. I. Pigment Red 178, C.I. I. Pigment Red 222 and the like.

Examples of orange or yellow pigments include C.I. I. Pigment Orange 31, C.I. I. Pigment Orange 43, C.I. I. Pigment Yellow 12,
C. I. Pigment Yellow 13, C.I. I. Pigment Yellow 14, C.I. I. Pigment Yellow 15, C.I.
I. Pigment Yellow 17, C.I. I. Pigment Yellow 93, C.I. I. Pigment Yellow 94, C.I. I.
Pigment Yellow 138 and the like.

The pigments for green or cyan include:
C. I. Pigment Blue 15, C.I. I. Pigment Blue 15: 2, C.I. I. Pigment Blue 15: 3,
C. I. Pigment Blue 16, C.I. I. Pigment Blue 60, C.I. I. Pigment Green 7 and the like.

These organic pigments can be used alone or in combination of two or more as desired. The amount of the pigment to be added is 2 to 20 parts by mass, preferably 3 to 15 parts by mass, based on the polymer.

The colorant can be used after surface modification. As the surface modifier, a conventionally known one can be used, and specifically, a silane coupling agent, a titanium coupling agent, an aluminum coupling agent and the like can be preferably used.

The toner obtained by the present invention is used by adding a so-called external additive for the purpose of improving fluidity and cleaning property in order to impart suitability as a recycled toner. These external additives are not particularly limited, and various inorganic fine particles, organic fine particles, and lubricants can be used.

As the inorganic fine particles used in the present invention, those having a particle diameter of 5 to 500 nm can be preferably used. This particle diameter is observed by a transmission electron microscope, and indicates a number average primary particle diameter measured by image analysis. As a material constituting the inorganic fine particles, various inorganic oxides, nitrides, borides and the like are suitably used. For example, silica,
Alumina, titania, zirconia, barium titanate,
Aluminum titanate, strontium titanate, magnesium titanate, zinc oxide, chromium oxide, cerium oxide, antimony oxide, tungsten oxide, tin oxide, tellurium oxide, manganese oxide, boron oxide, silicon carbide, boron carbide, titanium carbide, silicon nitride , Titanium nitride, boron nitride and the like. Further, the inorganic fine particles may be subjected to a hydrophobic treatment. When performing the hydrophobizing treatment, it is preferable to perform hydrophobizing treatment with a so-called coupling agent such as various titanium coupling agents and silane coupling agents, and silicone oil, and further, aluminum stearate, zinc stearate, and calcium stearate. It is also preferable to perform a hydrophobic treatment with a higher fatty acid metal salt such as

Hereinafter, the hydrophobizing agent for performing the hydrophobizing treatment and the treatment method will be described below. That is, examples of the titanium coupling agent include tetrabutyl titanate, tetraoctyl titanate, isopropyl triisostearoyl titanate, isopropyl tridecylbenzenesulfonyl titanate, and bis (dioctyl pyrophosphate) oxyacetate titanate. Further, as the silane coupling agent, γ- (2-aminoethyl) aminopropyltrimethoxysilane, γ- (2-aminoethyl) aminopropylmethyldimethoxysilane, γ-methacryloxypropyltrimethoxysilane, N-β- (N
-Vinylbenzylaminoethyl) γ-aminopropyltrimethoxysilane hydrochloride, hexamethyldisilazane, methyltrimethoxysilane, butyltrimethoxysilane,
Isobutyltrimethoxysilane, hexyltrimethoxysilane, octyltrimethoxysilane, decyltrimethoxysilane, dodecyltrimethoxysilane, phenyltrimethoxysilane, o-methylphenyltrimethoxysilane, p-methylphenyltrimethoxysilane, and the like.

Examples of fatty acids and metal salts thereof include undecylic acid, lauric acid, tridecylic acid, dodecylic acid, myristic acid, palmitic acid, pentadecylic acid, stearic acid, heptadecylic acid, arachiic acid, montanic acid, oleic acid, linoleic acid, Long-chain fatty acids such as arachidonic acid are mentioned, and as metal salts thereof, zinc, iron, magnesium,
Salts with metals such as aluminum, calcium, sodium, lithium and the like can be mentioned.

Examples of the silicone oil include dimethyl silicone oil, methylphenyl silicone oil, amino-modified silicone oil and the like.

These compounds are preferably added and coated in an amount of 1 to 10% by mass with respect to the inorganic fine particles.
It is 3 to 7% by mass. Further, these materials can be used in combination.

The surface may be treated with a polysiloxane having an ammonium salt as a functional group.

Further, as the inorganic fine particles, 5 to 50
Those having different particle diameters within the range of the number average primary particle diameter of 0 nm may be used in combination. Specifically, it is preferable to use a combination of a small particle size and a large particle size. A particle having a small particle diameter is about 5 to 50 nm, and a particle having a large particle diameter is one having a diameter exceeding 50 nm to 500 nm.

In addition to the above-mentioned inorganic fine particles, organic fine particles may be added. Examples of the organic fine particles include styrene resin fine particles, styrene acrylic resin fine particles, polyester resin fine particles, and urethane resin fine particles.

The composition of the resin fine particles is not particularly limited. Generally, vinyl-based organic fine particles are preferable. The reason for this is that it can be easily produced by a production method such as an emulsion polymerization method or a suspension polymerization method. Specifically, styrene, α-methylstyrene, p-chlorostyrene, 3,4-dichlorostyrene, p-phenylstyrene, p-ethylstyrene, 2,
Styrene or a styrene derivative such as 4-dimethylstyrene or pt-butylstyrene, a methacrylate derivative such as methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, isopropyl methacrylate, or 2-ethylhexyl methacrylate; Methyl acrylate, ethyl acrylate, isopropyl acrylate, n-butyl acrylate, t-butyl acrylate, isobutyl acrylate, n-octyl acrylate, 2-acrylate
Acrylic ester derivatives such as ethylhexyl, ethylene, propylene, olefins such as isobutylene, vinyl chloride, vinylidene chloride, vinyl bromide, vinyl fluoride,
Halogenated vinyls such as vinylidene fluoride, vinyl esters such as vinyl propionate and vinyl acetate, vinyl ethers such as vinyl methyl ether and vinyl ethyl ether, vinyl ketones such as vinyl methyl ketone, vinyl ethyl ketone and vinyl hexyl ketone; N-vinyl compounds such as N-vinylcarbazole, N-vinylindole and N-vinylpyrrolidone; vinyl compounds such as vinylnaphthalene and vinylpyridine; acrylonitrile, methacrylonitrile, acrylamide, N-butylacrylamide, N, N-dibutyl There are acrylic acid or methacrylic acid derivatives such as acrylamide, methacrylamide, N-butylmethacrylamide, and N-octadecylacrylamide. These vinyl monomers can be used alone or in combination.

The resin fine particles can be produced by an emulsion polymerization method or a suspension polymerization method. The emulsion polymerization method is a method in which the above-mentioned monomer is added to water containing a surfactant and emulsified, followed by polymerization. As the surfactant, sodium dodecylbenzenesulfonate, polyvinyl alcohol, an ethylene oxide adduct, Any substance that is used as a surfactant such as alcohol sodium sulfate can be used and is not particularly limited. In addition, the use of reactive emulsifiers, hydrophilic monomers,
For example, polymerization with a persulfate initiator such as vinyl acetate or methyl acrylate, or a method of copolymerizing a water-soluble monomer,
So-called non-emulsion polymerization methods such as a method using a water-soluble resin or oligomer, a method using a decomposable emulsifier, and a method using a cross-linkable emulsifier are also suitable. Examples of the reactive emulsifier include sulfonic acid salts of acrylic acid amide and salts of maleic acid derivatives. The non-emulsion polymerization method is not affected by the residual emulsifier, and is suitable when organic fine particles are used alone.

Polymerization initiators necessary for synthesizing resin fine particles include peroxides such as benzoyl peroxide and lauryl peroxide, and azo-based polymerization initiators such as azobisisobutyronitrile and azobisisovaleronitrile. Agents. The addition amount of these is preferably 0.1 to 2% by mass based on the monomer. If the amount is less than this, the polymerization reaction becomes insufficient, and the problem of residual monomer itself occurs. Further, when the amount is too large, a decomposition product of the polymerization initiator remains and affects the chargeability, and furthermore, the polymerization reaction is too early to cause a problem that the molecular weight becomes small. Further, in an emulsion polymerization method or the like, potassium persulfate, sodium thiosulfate, or the like can be used as a polymerization initiator.

Examples of the lubricant include salts of zinc, aluminum, copper, magnesium, calcium and the like of stearic acid, salts of zinc, manganese, iron, copper, magnesium and the like of oleic acid, zinc, copper, magnesium and the like of palmitic acid. Metal salts of higher fatty acids such as salts of calcium and the like, salts of zinc and linoleic acid such as calcium, salts of ricinoleic acid such as zinc and calcium and the like.

The addition amount of these external additives is preferably about 0.1 to 5% by mass based on the toner. << Manufacturing Step >> The manufacturing step of the toner of the present invention is a polymerization step of preparing resin particles by performing polymerization, the resin particles and the colorant particles in an aqueous medium using the resin particle dispersion and the colorant particle dispersion. A step of salting out and fusing (association step), a washing step of filtering the obtained associated particles from an aqueous medium to remove a surfactant and the like, a step of drying the obtained particles, and a further drying step. It comprises an external additive adding step of adding an external additive and the like to the particles.

Here, the aqueous medium is composed of water as a main component and has a water content of 50% by mass or more. Examples of the solvent other than water include an organic solvent soluble in water, such as methanol, ethanol, isopropanol, butanol, acetone, methyl ethyl ketone, and tetrahydrofuran. Preferred are alcoholic organic solvents such as methanol, ethanol, isopropanol and butanol.

The colorant itself may be used after surface modification. The colorant surface modification method is to disperse the colorant in a solvent,
After the addition of the surface modifier, the temperature is raised and the reaction is carried out. After completion of the reaction, the mixture is filtered, washed and filtered repeatedly with the same solvent, and dried to obtain a pigment treated with a surface modifier.

The colorant particles may be prepared by dispersing the colorant in an aqueous medium. This dispersion is performed in a state where the surfactant concentration in water is equal to or higher than the critical micelle concentration (CMC). The critical micelle concentration is associated with the concentration of the surfactant in the aqueous solution to form a thermodynamically stable aggregate-micelle (m
the concentration of the surfactant forming the icell.

The disperser for dispersing the pigment is not particularly limited, but is preferably an ultrasonic disperser, a mechanical homogenizer, a pressure disperser such as Manton-Gaulin or a pressure homogenizer, a sand grinder, a Getzman mill, a diamond fine mill, or the like. A medium type dispersing machine may be used.

As the surfactant used here, the above-mentioned surfactants can be used. In the salting-out / fusion step, a salting-out agent composed of an alkali metal salt or an alkaline earth metal salt is added as a coagulant having a critical coagulation concentration or more in water in which resin particles and colorant particles are present. Then, the step of heating the resin particles to a temperature equal to or higher than the glass transition point to promote salting out and simultaneously perform fusion. In this step, a method may be used in which an organic solvent that is infinitely soluble in water is added, and the glass transition temperature of the resin particles is substantially lowered to effectively perform fusion.

The alkali metal salt and alkaline earth metal salt as salting-out agents include lithium, potassium, sodium and the like as alkali metals, and magnesium, calcium, strontium, barium and the like as alkaline earth metals. And preferably potassium, sodium, magnesium, calcium and barium. Examples of the salt include chloride, bromide, iodine, carbonate, sulfate and the like.

Further, the organic solvent infinitely soluble in water includes methanol, ethanol, 1-propanol,
2-propanol, ethylene glycol, glycerin,
Acetone and the like are mentioned, and alcohols of methanol, ethanol, 1-propanol and 2-propanol having 3 or less carbon atoms are preferable, and 2-propanol is particularly preferable.

When the fusion in the present invention is carried out by salting out / fusion,
It is preferable to minimize the time of standing after adding the salting-out agent. Although the reason for this is not clear, there is a problem that the aggregation state of the particles fluctuates due to the standing time after salting out, the particle size distribution becomes unstable, and the surface properties of the fused toner fluctuate. appear. The temperature at which the salting-out agent is added must be at least equal to or lower than the glass transition temperature of the resin particles. The reason for this is that if the temperature at which the salting-out agent is added is higher than the glass transition temperature of the resin particles, the salting-out / fusion of the resin particles proceeds rapidly, but the particle size cannot be controlled, and There is a problem that particles having a particle size are generated. The range of the addition temperature may be lower than the glass transition temperature of the resin, but is generally 5 ° C to 55 ° C, preferably 10 ° C to 45 ° C.

In the present invention, it is preferable to use a method in which a salting-out agent is added at a temperature lower than the glass transition temperature of the resin particles, and thereafter, the temperature is raised as quickly as possible, and the temperature is raised to a temperature higher than the glass transition temperature of the resin particles. The time until the temperature rise is preferably less than 1 hour. Further, it is necessary to raise the temperature promptly, but the rate of temperature increase is preferably 0.25 ° C./min or more. The upper limit is not particularly clear, but when the temperature is raised instantaneously, salting out proceeds rapidly, and there is a problem that the particle size cannot be controlled. Thus, the upper limit is preferably 5 ° C./min or less.

Here, the particle diameter of the toner obtained by fusing the resin particles in the present invention is preferably 3 to 9 μm in volume average particle diameter. The volume average particle size of the toner is determined by using Coulter Counter TAII, Coulter Multisizer, SALD
1100 (Shimadzu laser diffraction particle size analyzer)
And the like. In the Coulter Counter TAII and the Coulter Multisizer, an aperture having an aperture diameter of 100 μm is used and 2.0 to 40 μm is used.
It shows what was measured using the particle size distribution in the range of μm.

The shape of the toner obtained by fusing has a shape factor represented by the following equation in the range of 1.3 to 2.2 and a shape factor in the range of 1.5 to 2.0. Is preferably 80% by number or more.

Shape factor = ((maximum diameter / 2) ² × π) / projected area This shape factor is obtained by taking a photograph in which the toner particles are magnified 500 times by a scanning electron microscope, and SCANNING IMAGE ANALYZ
Analyze the photographic image using "ER" (manufactured by JEOL Ltd.). At this time, the shape factor is measured by using the above formula using 500 toner particles.

When the arithmetic average value of the shape coefficient is less than 1.3, the shape becomes spherical, so that the external additive is easily buried in the toner surface during recycling, and the developing property and the transfer rate of the recycled toner are reduced. It deteriorates, the adhesion to the photoreceptor increases, and cleaning failure easily occurs.

On the other hand, when the shape factor exceeds 2.1, the irregular shape becomes high, and when mechanical stress is applied during recycling, the toner is crushed and fine powder is easily generated. Also in this case, the developability and the transfer rate are deteriorated, the adhesion to the photoreceptor is increased, and cleaning failure is apt to occur.

Further, when the number of toner particles having a shape coefficient in the range of 1.5 to 2.0 is 80% by number or more, the distribution of the shape can be made uniform. Since the amount of the irregular toner can be reduced, the above-described problem can be suppressed for a long period of time.

[Tonerization Step] In the tonerization step, the toner particles obtained above may be used as they are, but for the purpose of improving fluidity, chargeability and cleaning properties, for example, the above-mentioned external additive may be used. An agent may be added. As a method of adding the external additive, various known mixing devices such as a Turbula mixer, a Henschel mixer, a Nauter mixer, and a V-type mixer can be used.

The toner of the present invention may be used alone, or may be used as a magnetic or non-magnetic one-component toner, or may be used as a two-component developer by mixing with magnetic particles such as a carrier. .

The toner may contain a material capable of imparting various functions as a toner material in addition to the colorant. Specific examples include a fixing property improving agent and a charge control agent. These components are added at the stage of emulsion polymerization of the resin particles, the dispersion is added, the resin particles and the colorant particles are added at the same time in the salting-out / fusion step, and the toner particles are included in the toner. It can be added by various methods such as a method of adding it to an aqueous solution. As a preferred method, the charge control agent particles and / or
Or a method in which fixability improver particles are added in the form of a dispersion and the charge control agent particles and / or fixability improver particles in the state of the dispersion together with the resin particles and the colorant particles in the salting-out / fusion step described above And salting out / fusing.

As the fixability improving agent, various known ones which can be dispersed in water can be used. Specific examples include olefin waxes such as polypropylene and polyethylene, modified products thereof, natural waxes such as carnauba wax and rice wax, and amide waxes such as fatty acid bisamide.

The charge control agents are also various known ones.
What can be dispersed in water can also be used. Specifically, nigrosine dyes, metal salts of naphthenic acid or higher fatty acids, alkoxylated amines,
Quaternary ammonium salt compounds, azo-based metal complexes, salicylic acid metal salts or metal complexes thereof.

The particles of the charge control agent and the fixability improving agent have a number average primary particle diameter of 10 to 50 in a dispersed state.
Preferably, the thickness is about 0 nm.

<< Developer >> The developer used in the present invention includes:
Although it may be a one-component developer or a two-component developer, it is preferably a two-component developer. When used as a one-component developer, there is a method in which the toner is used as it is as a non-magnetic one-component developer.
It is used as a magnetic one-component developer by containing magnetic particles of about 5 μm. As a method of containing the same, it is common to make the non-spherical particles contain the same as the coloring agent.

Further, it can be used as a two-component developer by mixing with a carrier. In this case, as the magnetic particles, conventionally known materials such as metals such as iron, ferrite and magnetite, and alloys of these metals with metals such as aluminum and lead can be used. Particularly, ferrite particles are preferable. The magnetic particles preferably have a volume average particle size of 15 to 100 μm, more preferably 25 to 60 μm. The volume average particle size of the carrier is typically measured by a laser diffraction type particle size distribution analyzer “HELOS” equipped with a wet disperser (SYMPATIC (SYMPIC)
(ATEC)).

The carrier is preferably a carrier further coated with a resin or a so-called resin-dispersed carrier in which magnetic particles are dispersed in a resin. Although there is no particular limitation on the resin composition for coating, for example, an olefin resin, a styrene resin, a styrene / acrylic resin, a silicone resin, an ester resin, a fluorine-containing polymer resin, or the like is used. The resin for forming the resin dispersion type carrier is not particularly limited, and known resins can be used.For example, styrene acrylic resin, polyester resin, fluorine resin, phenol resin, and the like can be used. it can.

The toner for developing an electrostatic image of the present invention can be applied to general electrophotographic devices such as copiers, laser printers, LED printers, and liquid crystal shutter printers. It can be widely applied to devices such as recording, light printing, plate making, and facsimile.

FIG. 1 is a cross-sectional view showing one example of an image forming method having a toner for developing an electrostatic image and a developer according to the present invention.

In the present invention, reference numeral 4 denotes a photosensitive drum.
An organic photoconductor (OPC) layer, which is a photosensitive layer, is formed on the outer peripheral surface of an aluminum drum base, and rotates at a predetermined speed in the direction of the arrow. In the embodiment, the photosensitive drum 4 has an outer diameter of 60 mm.

In FIG. 1, exposure light is emitted from the semiconductor laser light source 1 based on information read by a document reading device (not shown). This is distributed by a polygon mirror 2 in the direction perpendicular to the plane of the paper of FIG. 1, and is radiated on the photoreceptor surface via an fθ lens 3 for correcting image distortion to form an electrostatic latent image. The photoreceptor is uniformly charged in advance by the charger 5 and starts rotating clockwise in synchronization with the timing of image exposure.

The electrostatic latent image on the surface of the photoreceptor is developed by a developing unit 6 and the formed toner image is transferred to an image support (recording material) 8 conveyed in a timely manner by a transfer unit 7. Is done. Further, the photosensitive drum 4 and the recording material 8
Are separated by a separator (separation pole) 9, and the toner image is transferred and carried on the recording material 8, guided to a fixing device 10 and fixed.

The untransferred toner and the like remaining on the photosensitive member surface are
It is cleaned by a cleaning device 11 of a cleaning blade type, and the remaining charge is removed by a pre-charging exposure (PCL) 12, and is uniformly charged again by the charger 5 for the next image formation.

The recording material is typically plain paper.
There is no particular limitation as long as an unfixed image after development can be transferred, and a PET base for OHP and the like are of course included.

The cleaning blade 13 has a thickness of 1 mm.
A rubber-like elastic body of about 30 mm is used, and urethane rubber is most often used as a material. Since this is used while being pressed against the photoconductor, heat is easily transmitted, and it is desirable to keep the photoconductor away from the photoconductor when the image forming operation is not performed.

In recent years, in the field of electrophotography and the like in which an electrostatic latent image is formed on a photoreceptor and this latent image is developed to obtain a visible image, it is easy to improve the image quality, convert, edit, etc., and obtain a high quality image. Research and development of an image forming method employing a digital method capable of forming are being actively conducted.

As a scanning optical system that modulates light with a digital image signal from a computer or a copy original used in the image forming method and apparatus, an acousto-optic modulator is interposed in a laser optical system, and the acousto-optic modulator uses the acousto-optic modulator. There are devices for modulation and devices for directly converting laser intensity using a semiconductor laser. A spot image is formed on a uniformly charged photoconductor from these scanning optical systems to form a dot-shaped image.

The beam emitted from the above-described scanning optical system has a round or elliptical luminance distribution approximating a normal distribution with a skirt spread left and right. One or both of the scanning direction and the sub-scanning direction has a very small circular or elliptical shape of 20 to 100 μm.

An electrophotographic image forming apparatus is constructed by integrally combining the above-described photoreceptor, a developing device, a cleaning device, and other components as a process cartridge, and this unit is configured to be detachable from the apparatus main body. You may.
Also, a process cartridge is formed by integrally supporting at least one of a charger, an image exposing unit, a developing unit, a transfer or separating unit, and a cleaning unit together with a photoreceptor. It may be configured to be detachable using a guide means such as a rail of the apparatus body.

When the image forming apparatus is used as a copying machine or a printer, the image exposure is performed by irradiating the photosensitive member with reflected light or transmitted light from the original, or by reading the original with a sensor and converting it into a signal. Scanning of a laser beam, driving of an LED array, or driving of a liquid crystal shutter array is performed by irradiating the photosensitive member with light.

Although the above-described electrophotographic image forming apparatus is an apparatus for forming a monochrome image, it goes without saying that the present invention can be similarly applied to a color image forming apparatus.

[0111]

EXAMPLES The present invention will be described below in detail with reference to examples, but embodiments of the present invention are not limited thereto. Production of Toner and Developer [Preparation of Colorant Particle Dispersion] In a resin container having an internal volume of 20 l, 0.90 kg of Adeka Hope LS-90 (sodium n-dodecyl sulfate manufactured by Asahi Denka Co., Ltd.) and 10.0 l of pure water were added. Stir and dissolve. To this solution, stir the legal 330
1.20 kg of R (carbon black manufactured by Cabot Corporation) is gradually added, and the mixture is stirred well for 1 hour after the addition. Next, continuous dispersion was performed for 18 hours using a sand grinder (medium type dispersion machine).

After dispersion, the particle diameter of the dispersion was measured using an electrophoretic light scattering photometer ELS-800 manufactured by Otsuka Electronics Co., Ltd., and as a result, the weight average diameter was 122 nm. The solid content concentration of the dispersion was 16.6% by mass as measured by a mass method based on standing drying. This dispersion is referred to as “colorant dispersion 1”. [Preparation of Low Molecular Weight Resin Particle Dispersion] 0.55 kg of sodium dodecylbenzenesulfonate (manufactured by Kanto Chemical Co., Ltd.) was placed in a 10 l stainless steel pot, and 4.0 l of ion-exchanged water was added.
And dissolve with stirring at room temperature. This is designated as an anionic surfactant solution A.

In a 10 l stainless steel pot, 0.14 kg of Newcol 565C (manufactured by Nippon Emulsifier) is added, 4.0 l of ion-exchanged water is added, and the mixture is stirred and dissolved at room temperature. This is designated as nonionic surfactant solution B.

223.8 g of potassium persulfate (manufactured by Kanto Chemical Co., Ltd.) was placed in a 20 l enamel pot, and ion-exchanged water 1 was added.
Add 2.0 l and stir and dissolve at room temperature. This is called initiator solution C.

An anionic surfactant solution A and a nonionic surfactant solution B are charged into a 100-liter GL (glass lining) reactor equipped with a temperature sensor, a cooling pipe, and a nitrogen introducing device, and stirring is started. Next, ion-exchanged water 44.
Add 0l.

The heating is started, and when the liquid temperature reaches 75 ° C., the initiator solution C is added. Thereafter, the liquid temperature is reduced to 7
While controlling the temperature at 5 ° C. ± 1 ° C., 12.1 kg of styrene, 2.88 kg of n-butyl acrylate and 1.0 methacrylic acid were added.
4 kg and 548 g of t-dodecyl mercaptan are introduced.

Further, the liquid temperature was raised to 78 ° C. ± 1 ° C.
Heating and stirring were performed for 7 hours. The liquid temperature is cooled to 40 ° C. or less, and the stirring is stopped. The mixture was filtered through a pole filter, and this was designated as “latex 1”.

The peak of the molecular weight distribution of the resin particles (hereinafter referred to as “resin particles 1”) in latex 1 measured by GPC was 12,500, and the molecular weight distribution Mw / Mn was 1.3. The weight-average particle diameter was measured using an electrophoretic light scattering photometer ELS-800 manufactured by Otsuka Electronics Co., Ltd.
It was 120 nm.

In the above reaction, latexes 2 and 3 having different molecular weight distributions were prepared by changing the reaction temperature and the amount of the chain transfer agent added. The resin particles in each latex are referred to as resin particles 2 and 3, and the peak of the molecular weight distribution and the molecular weight distribution are shown in Table 1. [Preparation of High Molecular Weight Resin Particle Dispersion] In a new 10 l stainless steel pot, 0.55 kg of sodium dodecylbenzenesulfonate (manufactured by Kanto Chemical Co., Ltd.) is added, 4.0 l of ion-exchanged pure water is added, and the mixture is stirred and dissolved at room temperature. This is referred to as an anionic surfactant solution D.

0.14 kg of Newcol 565C (manufactured by Nippon Emulsifier Co.) is placed in a 10 l stainless steel pot, 4.0 l of ion-exchange pure water is added, and the mixture is stirred and dissolved at room temperature. This is called Nonionic Surfactant Solution E.

In a 20 l enamel pot, 200.7 g of potassium persulfate (manufactured by Kanto Chemical Co., Ltd.) was added.
Add 2.0 l and stir and dissolve at room temperature. This is called initiator solution F.

In a 100-liter GL reactor (a stirring blade is a Faudler blade) equipped with a temperature sensor, a cooling pipe, a nitrogen introducing device, and a comb baffle, put the anionic surfactant solution D and the nonionic surfactant solution E, and stir. To start. Next, 44.0 l of ion-exchanged water is charged.

The heating is started, and when the liquid temperature reaches 70 ° C., the initiator solution F is added. At this time, styrene 1
1.0 kg, 4.00 kg of n-butyl acrylate, 1.04 kg of methacrylic acid, and t-dodecyl mercaptan 9.
And a solution obtained by previously mixing 02 g with the mixture.

Thereafter, the liquid temperature was controlled at 72 ° C. ± 2 ° C., and the mixture was heated and stirred for 6 hours. Further, the liquid temperature is set at 78 ° C.
The temperature was raised to ± 2 ° C., and the mixture was heated and stirred for 13 hours.

The temperature of the solution is cooled to 40 ° C. or less, and the stirring is stopped. The solution was filtered through a Pall filter, and the filtrate was used as Latex 4.

The peak of the molecular weight distribution of the resin particles (hereinafter referred to as “resin particles 4”) in the latex 4 measured by GPC was 243,000, and the molecular weight distribution Mw / Mn was 1.8.
Met. The weight average particle size was 113 nm from the electrophoretic light scattering photometer ELS-800 manufactured by Otsuka Electronics Co., Ltd.

In the above reaction, latexes 5 to 8 having different molecular weight distributions were prepared by changing the reaction temperature and the amount of the chain transfer agent added. The resin particles in each latex are referred to as resin particles 5 to 8, and the peak of the molecular weight distribution and the molecular weight distribution are shown in Table 1. [Preparation of salting-out agent solution] 5.36 kg of sodium chloride (manufactured by Wako Pure Chemical Industries) as a salting-out agent in a 35 l stainless steel pot
And 20.0 l of ion-exchanged water, and dissolve with stirring. This is designated as sodium chloride solution G. [Salt precipitation / fusion of resin particles and colorant particles] Temperature sensor,
100 l with cooling tube, nitrogen inlet, comb baffle
20. The latex 1 in which the low-molecular-weight resin particles prepared above were dispersed in a SUS reaction vessel (the stirring blade was an anchor blade).
0 kg, 5.2 kg of latex 5 in which high molecular weight resin particles are dispersed, 0.4 kg of colorant dispersion 1 and WAX emulsion (polypropylene emulsion having a number average molecular weight of 3000: number average primary particle diameter = 120 nm / solid content = (29.9%) 6.82 kg and ion exchange water 20.0 k
g and stir. Then, the mixture was heated to 40 ° C., and sodium chloride solution G and isopropanol (manufactured by Kanto Chemical Co., Ltd.)
6.00 kg of nonionic surfactant solution H are added in this order. Then, after leaving it to stand for 10 minutes, the temperature is started to rise to a liquid temperature of 85 ° C. in 60 minutes. Liquid temperature 85 ° C
Heat and stir at ± 2 ° C. for 6 hours for salting out / fusion. Thereafter, the mixture is cooled to 40 ° C. or less and the stirring is stopped. Aperture 45
The solution was filtered through a sieve of μm to obtain an association liquid. [Washing and drying of associated particles] Then, using Nutsche,
Non-spherical particles in the form of a wet cake were collected by filtration from the associated liquid. Thereafter, the substrate was washed with ion-exchanged water.

The wet cake-like non-spherical particles having been washed as described above are taken out from the nutsche, and the whole paper vat 5 is removed.
Spread them into pieces into pieces. After covering with kraft paper, it was dried with a blow dryer at 40 ° C. for 100 hours.

The dried block-shaped non-spherical particles were crushed by a Henschel pulverizer. [Preparation of Toner] Toner 1 was obtained by adding 1% by mass of hydrophobic silica (primary average particle diameter = 12 nm) to the above non-spherical particles.

In the salting out / fusing step of the resin particles and the colorant particles, the subsequent steps were the same except that the combination of the latex in which the low molecular weight resin particles were dispersed and the latex in which the high molecular weight resin particles were dispersed were changed. And toner 2-9
I got Table 2 shows this latex combination.

The peak of molecular weight distribution measured for each toner, Mw / Mn, shape factor, shape factor
Table 2 shows the ratio of 2.0 and the volume average particle diameter measured by the Coulter Multisizer. [Preparation of Developer] Toners 1 to 9 and a ferrite carrier coated with a styrene acrylic resin and having a volume average particle diameter of 45 μm were mixed to prepare Developers 1 to 9 having a toner concentration of 9% and used for print evaluation. .

[0132]

[Table 1]

[0133]

[Table 2]

Evaluation [Actual Photo Test] The thus obtained developers 1 to 9 were unitized with a digital copying machine Konica 7060 (a photoconductor, a charger, a developing device, a cleaning device, and a static eliminator) by Konica Corporation. ) Was evaluated. Table 3 shows the evaluation results. [Evaluation of Copy Image Quality] The following evaluation method was used to evaluate the cleaning stability and the charging stability of the developer based on (toner scattering, image density, fog).

Evaluation was made at normal temperature and low humidity (24 ° C./60% R).
In H), a character image with a pixel rate of 1% (an original image in which a character image with a pixel rate of 7%, a portrait of a person, a solid white image, and a solid black image are each １ ／ equally divided) is A4. 100,000 copies were made in the intermittent printing mode, and a halftone, solid white image and solid black image were printed every 1000 sheets. (1) Regarding poor cleaning, the presence or absence of white spots (those having a diameter of 0.3 mmφ or more) existing on a solid black image was evaluated, and the number of white spots where 5 or more occurred was evaluated. The evaluation criteria are as follows.

Rank A: 1 or less white spots caused by poor cleaning in 100,000 copy images. Rank B: 2 to 5 white spots caused by poor cleaning in 100,000 copy images. Practically acceptable level Rank C: 6 or more white spots caused by poor cleaning in 100,000 copy images. Practically problematic level (2) Regarding toner scattering, the number of white stripes on a halftone image generated due to contamination by toner attached to the band electrode was evaluated. The evaluation criteria are as follows.

Rank A: 1 or less white streaks caused by band electrode contamination in 100,000 copy images, Rank B: 2 to 5 white streaks caused by band electrode contamination in 100,000 copy images. Practically no problem level Rank C: 6 or more white stripes caused by contamination of the band electrode in 100,000 copy images. Practically problematic level (3) The image density was measured by measuring the absolute reflection density of a solid black image using a densitometer RD-918 manufactured by Macbeth Co., and comparing the initial image and the image after 100,000 sheets. This density change is 0.10
Within this range, it can be said that there is little change in image quality and there is no problem. (4) For fog, a solid white image was used, and the relative reflection density with the reflection density of paper being "0" was measured using a density meter RD-918 manufactured by Macbeth Co., Ltd. Were compared. If the fog density is 0.010 or less,
Fog is practically acceptable. (Developing conditions) Photoconductor; laminated organic photoconductor DC bias: -500 V Dsd (distance between photoconductor and developing sleeve): 600 μm Developer layer regulation: magnetic H-Cut method Developer layer thickness: 700 μm・ Developing sleeve diameter: 40mm (Cleaning condition) Rubber hardness J for cleaning
ISA 70 °, rebound resilience 25, thickness 2mm, free length 9m
A polyurethane elastic rubber blade having a contact angle of 20 ° and a pressing force of 20 g / cm was applied in a counter direction to the rotation of the photosensitive member at a contact angle of 20 ° by a weight load method.

The rubber hardness and rebound resilience are measured as JISA hardness and rebound resilience according to JIS K6301 vulcanized rubber physical test method. (Fixing Conditions) As the fixing device, a pressure fixing type heat fixing device was employed. The configuration of the fixing device and the fixing conditions are as follows.

The upper roller is made of a column-shaped aluminum alloy having a diameter of 30 mm and a total width of 310 mm, the surface of which is coated with a tetrafluoroethylene-perfluoroalkylvinyl ether copolymer (PFA) and having a total width of 310 mm and having a heater built in the center and having a thickness of 2 mm. And a sponge-like silicone rubber whose surface is coated with a tetrafluoroethylene-perfluoroalkyl ether copolymer (PFA) (Asker C hardness = 4).
8: 8 mm in thickness). The nip pressure was 1.1 kg / cm2 (total load = 19.8 kgf) and the nip width was 5.8 mm.

As a cleaning mechanism for the fixing device, polydiphenylsilicone (having a viscosity of 10
0 cp) was used. The fixing temperature is controlled by the surface temperature of the upper roll.
The set temperature was 75 ° C. The amount of silicone oil applied was 0.8 μg / cm ² .

[0141]

[Table 3]

[0142]

According to the toner for developing an electrostatic image of the present invention, a high quality image can be formed for a long period of time with excellent cleaning properties and charge stability.

According to the method for producing a toner for developing an electrostatic image of the present invention, a high quality image can be formed over a long period of time with excellent cleaning properties and charge stability.

According to the developer for an electrostatic image of the present invention, it is possible to form a high quality image for a long period of time with excellent cleaning property and charge stability.

According to the image forming method of the present invention, a high quality image can be formed over a long period of time with excellent cleaning properties and charge stability.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating an example of an image forming method including a toner for developing an electrostatic image and a developer according to the present invention.

[Explanation of symbols]

 Reference Signs List 1 semiconductor laser light source 2 polygon mirror 3 fθ lens 4 photoreceptor drum 5 charger 6 developing device 7 transfer device 8 image support (recording material) 9 separator 10 fixing device 11 cleaning device 12 pre-charge exposure 13 cleaning blade

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Makoto Kono 2970 Ishikawacho, Hachioji-shi, Tokyo Konica Corporation F-term (reference) 2H005 AA01 AB03 BA06 CA04 DA07 EA06

Claims (6)

[Claims] 1. A toner obtained by salting out / fusing at least the resin particles and the colorant particles from a dispersion solution containing the resin particles and the colorant particles, the resin component of the toner measured by GPC. Has a molecular weight distribution of at least 1,500 to
It has peaks or shoulders at 20,000 and 50,000 to 500,000, and the molecular weight distribution (ML) derived from the peak or shoulder on the low molecular weight side is Mw / Mn.
= 1.2 to 4.0, and the molecular weight distribution (MH) derived from one peak or shoulder on the high molecular weight side is Mw
/Mn=2.0 to 30.0, the toner for developing an electrostatic image. 2. The electrostatic image developing toner according to claim 1, wherein the molecular weight distribution ML on the low molecular weight side and the molecular weight distribution MH on the high molecular weight side satisfy MH ≧ ML. 3. A method for producing a toner by salting out / fusing resin particles and colorant particles from a dispersion solution containing resin particles and colorant particles, wherein two or more types of resin particles are used as the resin particles. Using resin particles, one of them has a peak or shoulder at 1,500 to 20,000 in the molecular weight distribution measured by GPC, and Mw / Mn = 1.2 to
Low molecular weight resin particles having a molecular weight of 4.0
A method for producing a toner for developing an electrostatic image, comprising high molecular weight resin particles having a peak or shoulder at 000 to 500,000 and having Mw / Mn = 2.0 to 30.0. 4. The molecular weight distribution Mw of the low molecular weight resin particles.
/ The Mn and ML _P, the molecular weight distribution of high molecular weight resin particles M
When a w / Mn was MH _P, claim 3 manufacturing method of the electrostatic image developing toner, wherein the a MH _P ≧ ML _P. 5. An electrostatic image developer comprising: the toner for developing an electrostatic image according to claim 1; and a carrier in which magnetic particles are coated with a resin. 6. An image forming method for transferring a toner image produced through an electrification, exposure, and development process to a recording material using an electrophotographic photoreceptor and cleaning the toner remaining on the photoreceptor. An image forming method, wherein development is performed using the developer containing the toner for developing an electrostatic image described in 1 or 2.