JP2000250263A - Electrostatic latent image developing toner, its production developer using same and image forming method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve transferability to an image support and to maintain high image quality over a long period of time. SOLUTION: At least resin particles and colorant particles are salted out and fused to obtain the objective toner. The resin particles are obtained by adding a polymerizable monomer to an aqueous solution containing a dissolved polymerization initiator at an average addition rate of 0.1-5.0 wt.% of the entire polymerizable monomer per 1 min and polymerizing the monomer.

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 latent image (hereinafter also referred to simply as "toner"), a method for producing the same,
The present invention relates to a developer using the toner and an image forming method.

[0002]

2. Description of the Related Art As a toner for copiers and printers utilizing electrostatic latent image development, toner by a pulverization method is currently the mainstream, but in recent years, the demand for higher image quality from the market has increased, and the cost has been reduced. Since small-sized particles having a sharp particle size distribution can be produced, a method for producing a polymerized toner using an emulsion polymerization method, a suspension polymerization method, a dispersion polymerization method, or the like has been actively proposed (for example, an emulsion polymerization method). Are disclosed in JP-A-63-186253 and JP-A-6-329.
947, JP-A-9-96919, etc.).

[0003] Among them, a so-called emulsion-association-type polymerized toner production method in which emulsion polymerized particles are used to form an aggregate with a colorant or the like and then fused to produce non-spherical particles due to the characteristics of the method. For this reason, there is an advantage that a toner having a small particle diameter and excellent cleaning properties can be produced as compared with a suspension polymerization toner that can obtain a spherical toner.
However, in the conventional method for producing an emulsion-association type polymerized toner, when the toner is mounted on an actual copier / printer, problems such as repelling of characters may occur at the time of transfer to an image support. Although the reason for this is not clear, it is presumed that there is a problem in the uniformity of assembling the particles, and cissing is likely to occur due to the presence of a low-charge toner at the time of transfer to the image support. You.

[0004]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a toner for developing an electrostatic latent image which has good transferability to an image support and can maintain high image quality for a long period of time. An object of the present invention is to provide a toner for developing a latent electrostatic image and a method for producing the same, and a developer and an image forming method using the toner for developing a latent electrostatic image of the present invention.

[0005]

The above object of the present invention is achieved by the following constitution.

[0006] 1. In an electrostatic latent image developing toner in which at least resin particles and colorant particles are salted out and fused, the average addition rate of the polymerizable monomer in an aqueous solution in which the resin particles dissolve a polymerization initiator is increased. 0.1% of all polymerizable monomers per minute
A toner for developing an electrostatic latent image, wherein the resin particles are polymerized by being added at a weight percentage of 5.0 to 5.0 weight%.

[0007] 2. The average rate of addition of the polymerizable monomer is from 0.3% by weight to 3.0% by weight of the total polymerizable monomer per minute.
2. The toner for developing an electrostatic latent image according to item 1, wherein

[0008] 3. In a method for producing a toner for developing an electrostatic latent image having at least resin particles and colorant particles, an average addition rate of a polymerizable monomer in an aqueous solution in which a polymerization initiator is dissolved is set at a rate of every polymerizable monomer per minute. 0.1% to 5% by weight of the monomer
A method for producing a toner for developing an electrostatic latent image, wherein salting out and fusing the resin particles and the colorant particles added at 0% by weight and polymerized.

4. 4. The method for producing a toner for developing an electrostatic latent image according to the above item 3, wherein the average addition rate is from 0.3% by weight to 3.0% by weight of all polymerizable monomers per minute.

[0010] 5. In a developer having magnetic particles and a toner for developing an electrostatic latent image obtained by salting out and fusing at least resin particles and colorant particles, the resin particles are polymerized in an aqueous solution in which a polymerization initiator is dissolved. A developer characterized in that the resin particles are polymerized by adding a monomer at an average addition rate of 0.1% by weight to 5.0% by weight of all polymerizable monomers per minute.

6. 6. The developer according to the above item 5, wherein the average addition rate is from 0.3% by weight to 3.0% by weight of the total polymerizable monomer per minute.

7. The latent image formed on the electrostatic latent image forming body is developed with a developer having at least a toner for developing an electrostatic latent image, and then transferred to an image support and thermally fixed to obtain an image forming method. Wherein the toner is a toner for developing an electrostatic latent image in which at least resin particles and colorant particles are salted out and fused, and the resin particles are polymerizable monomers in an aqueous solution in which a polymerization initiator is dissolved. Particles added at an average addition rate of 0.1% by weight to 5.0% by weight of the total polymerizable monomer per minute and polymerized, and the particles remaining on the electrostatic latent image forming body are polymerized. An image forming method comprising cleaning a toner for developing a latent charge image.

8. 8. The image forming method according to the item 7, wherein the average addition rate is from 0.3% by weight to 3.0% by weight of the total polymerizable monomer per minute.

That is, the present inventors have made intensive studies and as a result,
The present inventors have found that the object of the present invention can be achieved by paying attention to the properties of the particles during the emulsion polymerization, and have completed the present invention.

In the present invention, a specific method is used to add the polymerizable monomer during the emulsion polymerization, so that the surface properties of the emulsion polymer particles produced in the emulsion polymerization can be made uniform. As a result, the toner particles themselves formed by associating using the particles can also have uniform properties, have a uniform charge amount, and have problems such as repelling during transfer to the image support. Can be obtained.

The toner of the present invention is obtained by salting out and fusing at least resin particles and colorant particles prepared by emulsion polymerization. This salting-out, and fusion, the salting-out agent is added to water in which the emulsion polymerization particles and the colorant particles are dispersed,
If necessary, an infinitely soluble organic solvent is added, followed by heating for salting out and simultaneously fusing to prepare 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 to prepare toner particles. Salting out,
The uniformity of the toner particles formed by fusing is not impaired, and a toner having a uniform chargeability can be stably obtained.

Hereinafter, the present invention will be described in detail.

<< Material >> [Monomer] As the polymerizable monomer, a radical polymerizable monomer is used as 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. .

(Meth) acrylic ester monomers include methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, phenyl acrylate, methyl methacrylate, 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 monomer include ethylene, propylene, isobutylene, 1-butene, 1-pentene, 4-methyl-1-pentene and the like.

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

The halogenated olefin monomers include:
Vinyl chloride, vinylidene chloride, vinyl bromide and the like.

(2) Crosslinking Agent As the crosslinking agent, a radical polymerizable crosslinking agent may be added in order 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 Radical polymerizable monomer having an acidic group or radical polymerizable monomer having a basic group For example, an amine compound such as a carboxyl group-containing monomer, a sulfonic acid group-containing monomer, a primary amine, a secondary amine, a tertiary amine, and a quaternary ammonium salt may be used. it can.

Examples of the radical polymerizable monomer having an acidic group include carboxylic acid group-containing monomers such as 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 quaternary of the above four compounds. 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 can be mentioned.

In the present invention, the above-mentioned radical polymerizable monomers can be used in combination, and are preferably an aromatic vinyl monomer, a (meth) acrylate monomer, and a radical polymerizable monomer having an acidic group. It is preferable to use a monomer or a radical polymerizable monomer having a basic group.

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 0.1 to 15% of the whole monomer. Preferably, the radical polymerizable cross-linking agent is used in the range of 0.1 to 10% by weight, based on the total radical polymerizable monomer, depending 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 lowest 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 (such as sodium dodecylbenzenesulfonate and sodium polyoxyethylenebenzenesulfonate) and sulfate salts (sodium dodecyl sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate). And the like, and fatty acid salts (such as sodium oleate, sodium laurate, sodium caprate, sodium caprylate, sodium caproate, potassium stearate, and calcium oleate).

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.

Further, a fluorine-based surfactant can also be used.

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 added is about 2 to about 20 parts, preferably about 3 to 15 parts, 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 weight.

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

The pigments for magenta or red include:
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 pigments for orange or yellow 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.

Examples of green or cyan pigments 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 added is about 2 to about 20 parts, preferably about 3 to 15 parts, 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.

Examples of the silane coupling agent include alkoxysilanes such as methyltrimethoxysilane, phenyltrimethoxysilane, methylphenyldimethoxysilane and diphenyldimethoxysilane, siloxanes such as hexamethyldisiloxane, γ-chloropropyltrimethoxysilane, vinyl Trichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane,
γ-ureidopropyltriethoxysilane and the like.

As the titanium coupling agent, for example,
TTS, 9S, 38S, 41B, 46B, 5B, which are commercially available under the trade name "Plenact" manufactured by Ajinomoto Co.
5, 138S, 238S, etc., commercial products A-
1, B-1, TOT, TST, TAA, TAT, TL
A, TOG, TBSTA, A-10, TBT, B-2,
B-4, B-7, B-10, TBSTA-400, TT
S, TOA-30, TSDMA, TTAB, TTOP and the like.

As the aluminum coupling agent, for example, "Plenact AL-M" manufactured by Ajinomoto Co., etc. may be mentioned.

These surface modifiers are added to the colorant in an amount of 0.1%.
It is preferably added in an amount of from 0.1 to 20% by weight, more preferably about 0.1 to 5% by weight.

A so-called external additive can be added to the toner obtained in the present invention for the purpose of improving fluidity and cleaning property. These external additives are not particularly limited, and various inorganic fine particles,
Organic particulates and lubricants can be used.

Conventionally known inorganic fine particles can be used. Specifically, silica, titanium, alumina fine particles and the like can be preferably used. These inorganic fine particles are preferably hydrophobic. Specifically, as silica fine particles, for example, Nippon Aerosil Co., Ltd.
Commercially available products R-805, R-976, R-974, R-
972, R-812, R-809, HVK-2150, H-200 manufactured by Hoechst Co., Ltd., and commercial products TS-720, TS-530, TS-610, H manufactured by Cabot Co., Ltd.
-5, MS-5 and the like.

Examples of the titanium fine particles include commercially available products T-805 and T-604 manufactured by Nippon Aerosil Co., Ltd., and commercially available products MT-100S and MT-100B manufactured by Teika Co., Ltd.
MT-500BS, MT-600, MT-600SS,
JA-1, commercial product TA-300S manufactured by Fuji Titanium Co., Ltd.
I, TA-500, TAF-130, TAF-510,
TAF-510T, commercial product IT- manufactured by Idemitsu Kosan Co., Ltd.
S, IT-OA, IT-OB, IT-OC and the like.

Examples of the alumina fine particles include commercial products RFY-C and C-604 manufactured by Nippon Aerosil Co., Ltd., and commercial products TTO-55 manufactured by Ishihara Sangyo Co., Ltd.

As the organic fine particles, spherical organic fine particles having a number average primary particle diameter of about 10 to 2000 nm can be used. As this, a homopolymer such as styrene or methyl methacrylate or a copolymer thereof can be used.

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

The addition amount of these external additives is preferably about 0.1 to 5% by weight based on the toner.

<< Production Step >> The production step of the polymerized toner of the present invention is an emulsion polymerization step of preparing resin particles by emulsion polymerization, and salting out and melting after adding a colorant particle dispersion to the resin particle dispersion. Salting-out / fusing step of applying toner particles, washing step of filtering the obtained toner particles from water to remove a surfactant and the like, drying step of drying the obtained toner particles, and further drying. An external additive adding step (toner forming step) in which the obtained toner is subjected to a crushing treatment as necessary (crushing step) and an external additive is added.

Hereinafter, each step will be described.

[Emulsion Polymerization Step] The emulsion polymerization step of the present invention is basically an emulsion polymerization conventionally generally known, except for the rate of addition of the polymerizable multimer limited in the present invention. Although not particularly limited, for example, the following method can be used.

First, a required amount of a radical polymerization initiator is dissolved in water. Then, after degassing with a nitrogen stream,
After heating and reaching a predetermined polymerization temperature, the radical polymerizable monomer is added under the addition conditions of the present invention. In the present invention, the addition rate is such that the average addition rate of the polymerizable monomer to be added is from 0.1% by weight to 5.0% of all the polymerizable monomers per minute.
%, Preferably from 0.3% to 3.0% by weight of the total polymerizable monomer per minute.

When the average addition rate is lower than 0.1% by weight or less of the polymerizable monomer, the conversion is often 98% or less, and the unreacted monomer remains or oligomers are generated. Or It is considered that the transferability is deteriorated because the distribution of the surface properties of the toner particles is widened by the influence of these molecules.

On the other hand, the average rate of addition was 5.
When the amount is larger than 0% by weight, aggregates are often generated during polymerization, and it is considered that particles different from polymer fine particles obtained at an appropriate rate of addition are generated. It is considered that the transferability is deteriorated because the polymer fine particles thus produced have an adverse effect on the transferability.

The apparatus for adding the polymerizable monomer into the reaction phase is not particularly limited, but for example, a fixed-rate liquid sending pump, a dropping funnel and the like can be used.

When a plurality of radically polymerizable monomers are used, it is preferable to dissolve them and add them as a uniform solution. Incidentally, the average addition rate of the present invention is defined by a percentage based on all the radical polymerizable monomers used.

When a chain transfer agent is used for controlling the molecular weight, it is added by mixing with a radical polymerizable monomer.

The polymerization temperature and time may be set as long as the emulsion polymerization occurs. Usually, the polymerization is carried out under a nitrogen stream.

This emulsion polymerization step may be performed a plurality of times under different conditions depending on the desired physical properties of the toner.
Additional polymerization can also be performed where the previous polymerization liquid is present.

Further, a plurality of resin particles having different molecular weights or different compositions may be separately prepared, and the plurality of resin particles may be subjected to salting-out / fusion as described below to form a toner. In this case, it is particularly preferable to use resin particles having different molecular weights from the viewpoint of improving the fixability of the toner.
In this case, it is preferable that all of the plurality of resin particles satisfy the configuration of the present invention. The reason for this is that, when a plurality of resin particles having different addition rates of the polymerizable monomer are used, uniform salting-out / fusion cannot be performed, and the shape of the formed toner particles is not good. This is because the problem of uniformity is likely to occur. That is, when all of the plurality of resin particles satisfy the configuration of the present invention, a uniform toner can be prepared.

The resin particles according to the present invention may have a glass transition temperature (abbreviated as Tg) in the range of 10 to 75 ° C., more preferably 40 to 65 ° C. The softening point of the resin particles is preferably in the range of 80 to 220C. As the composition of the resin particles, those containing a radical polymerizable monomer having an acidic group or a radical polymerizable monomer having a basic group are particularly preferable. This content is preferably about 0.1 to 20% by weight based on the whole polymer.

The molecular weight of the resin particles according to the present invention is not particularly limited, but is usually from 2,000 to 2,000 in weight average molecular weight.
1,000,000, preferably 8,000-500,
000. The particle diameter of the resin particles prepared by emulsion polymerization is about 20 to 500 nm in weight average diameter.

Here, the softening point of the resin particles indicates a value measured using a Koka type flow tester (manufactured by Shimadzu Corporation). Specifically, the Koka type flow tester “CF
Using a T-500 "(manufactured by Shimadzu Corporation), a sample of 1 cm ³ was melted and flown out under the conditions of a pore diameter of a die of 1 mm, a length of 1 mm, a load of 20 kg / cm ² and a heating rate of 6 ° C./min. The temperature corresponding to 1/2 of the height from the outflow start point to the outflow end point is shown as the softening point.

The glass transition point of the resin particles is defined by DSC
The intersection between the baseline and the slope of the endothermic peak is defined as the glass transition point. Specifically, using a differential scanning calorimeter, the temperature was raised to 100 ° C., and at that temperature, 3 mi
After being left for n minutes, it is cooled to room temperature at a temperature drop of 10 ° C./min. Next, the sample was heated at a rate of 10 ° C./mi.
When measured at n, the intersection of the extension of the baseline below the glass transition point and the tangent that indicates the maximum slope from the peak rising portion to the peak apex is indicated as the glass transition point.

As a measuring device, DSC-7 manufactured by Perkin Elmer, etc. can be used.

The molecular weight distribution of the resin particles indicates the molecular weight in terms of styrene measured by GPC.

The method for measuring the molecular weight of a resin by GPC is described in US Pat.
It is a measurement by GPC (gel permeation chromatography) using HF as a solvent. That is, the measurement sample is 0.5 to 5 mg, more specifically, 1 mg for THF.
, And stirred at room temperature using a magnetic stirrer or the like to sufficiently dissolve. Then, after treating with a membrane filter having a pore size of 0.45 to 0.50 μm, the mixture is injected into GPC. GPC measurement conditions were as follows: stabilize the column at 40 ° C., and set the THF to 1 c / min.
c at a flow rate of 1 mg / cc,
Inject μl and measure. The column is preferably used in combination with a commercially available polystyrene gel column.
For example, Shodex GPC KF-
801,802,803,804,805,806,8
07 combination or TSKgelG1000 manufactured by Tosoh Corporation
H, G2000H, G3000H, G4000H, G5
000H, G6000H, G7000H, TSK gu
and ard column combinations. As the detector, a refractive index detector (IR detector) or a UV detector may be used. In measuring the molecular weight of a sample, the molecular weight distribution of the sample is calculated using a calibration curve created using monodisperse polystyrene standard particles. As polystyrene for preparing a calibration curve, about 10 points may be used.

The particle diameter of the resin particles is a weight average particle diameter measured using the above-mentioned dispersion liquid with an electrophoretic light scattering photometer ELS-800 manufactured by Otsuka Electronics Co., Ltd.

[Salt Salting Out / Fusing Step] A non-spherical toner is produced by salting out using the resin particles produced in the polymerization step and fusing.

In this case, the resin particles and the colorant particles are salted out in water and fused.

In addition to the colorant, a releasing agent and a charge controlling agent, which are constituents of the toner, can be added in this step.

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 are prepared by dispersing a colorant in water. 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 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 type homogenizer, a sand grinder, a Getzman mill, a diamond fine mill, or the like. The medium type disperser is fried.

As the surfactant used here, the above-mentioned surfactants can be used.

In the step of salting out / fusing, a salting-out agent comprising an alkali metal salt, an alkaline earth metal salt or the like is dissolved in water in which resin particles and colorant particles are present. And then heating to above the glass transition point of the resin particles to promote salting out and simultaneously fuse. 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.

Here, 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, as the organic solvent infinitely soluble in water, methanol, ethanol, 1-propanol,
2-propanol, ethylene glycol, glycerin,
Acetone and the like can be 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.

In the case of performing the salting-out / fusing of the present invention, it is preferable to minimize the time for which the salting-out agent is allowed to stand after addition. 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 necessary to use a method in which the 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 the glass transition temperature of the resin particles. is there. The time until the temperature rise is preferably less than 4 hours. Further, it is necessary to raise the temperature promptly, but the rate of temperature increase is preferably 0.10 ° 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 size of the toner obtained by salting out / fusing is preferably 3 to 10 μm in terms of volume average particle size. The volume average particle size of this toner is determined by the Coulter Counter TA.
-II, Coulter Multisizer, SLAD1100 (Shimadzu Corporation laser diffraction particle size analyzer) or the like. Aperture diameter = 10 for Coulter Counter TA-II and Coulter Multisizer
The figure shows a value measured using a particle size distribution in the range of 2.0 to 40 μm using an aperture of 0 μm.

[Filtration / Washing Step] The toner particles obtained in the salting-out / fusion step are filtered and washed to remove impurities such as a surfactant and a salting-out agent attached to the toner particles. . As this method, filtration is performed by centrifugation, Nutsche, filter press, or the like, and then washing is performed with washing water.

[Drying Step] The toner after washing and filtration is dried and used. The drier used at this time is not particularly limited, but a spray drier, a vacuum freeze drier, a reduced pressure drier and the like are used, and preferably, a stationary shelf drier, a mobile shelf drier, a fluidized bed drier, A rotary dryer, a stirring dryer and the like are used. At the time of drying, the water content is preferably 5% by weight or less, more preferably 2% by weight or less.

[Crushing Step] This step is not particularly necessary in some cases, but may be in a weakly aggregated state after drying. In this case, a jet mill, a Henschel mixer,
The crushing may be performed by using a mechanical crushing device such as a coffee mill or a food processor.

[Tonerization Step] In the tonerization step, the toner particles obtained as described above may be used as they are. 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 mixed with magnetic particles such as a carrier and used as a two-component developer.

The toner may contain, in addition to the colorant, a material capable of imparting various functions as a toner material. 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 controlling 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 a one-component developer or a two-component developer may be used, a two-component developer is preferable. When used as a one-component developer, there is a method of using the toner as it is as a non-magnetic one-component developer, but usually 0.1 to 5 μm
About m of magnetic particles are contained and used as a magnetic one-component developer. 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 mixed with a carrier and used as a two-component developer. 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.

<< Image Forming Method >> Next, the image forming method of the present invention will be described.

FIG. 1 is a sectional view showing an example of a developing device (developing device) used in the image forming method of the present invention. In this figure, reference numeral 41 denotes a developing sleeve which is a developer carrying body having a fixed magnet 42 therein, 46 denotes a regulating rod which is a developer carrying amount regulating member, 47 denotes a scraper which is a developer scraping member, and 48 denotes a scraper which is a developer scraping member. A stirring roller as a developer stirring member, 4
Reference numeral 9 denotes a casing of a developing device, 50 denotes a two-component developer including a toner T and a carrier C, 51 denotes a power supply as bias applying means, and 10 denotes an image forming body in which a photosensitive layer 12 is formed on a conductive substrate 11. body drum, D ₁ is the closest distance of the developing sleeve 41 and the photosensitive drum 10, also arrow of the photosensitive drum 10 and the developing sleeve 41 shows the direction of rotation.

The developing sleeve 41 is made of, for example, aluminum,
It is a cylinder of 0.5 to 3 cm in diameter made of non-magnetic and conductive metal such as stainless steel, and has a surface roughness (Rz) of 1 to 3.
It is processed to be 30 μm. Inside the developing sleeve 41, 4 to 12 magnetized to the N pole or the S pole
A magnet body 42 such as a columnar or split chopstick-shaped (column-shaped) aggregate having magnetic poles is fixedly provided, and the developing sleeve 41 is rotatable with respect to the magnet body 42.

The casing 49 is a casing made of, for example, an insulating resin such as acryl or polycarbonate. Inside the casing 49, the developing sleeve 41 including the fixed magnet body 42, the supply roller 45, and the scraper 4 are provided.
7 and the stirring roller 48 are disposed,
A regulating rod 46 is disposed at the outlet of the control rod.

A two-component developer 50 composed of toner T and carrier C is stored inside the casing 49. The two-component developer 50 is stirred and mixed by the stirring roller 48 and is supplied by the supply roller 45 and adheres to the developing sleeve 41 to form a magnetic brush. The magnetic brush is transported while the transport amount is regulated by the regulating rod 46 as the developing sleeve 41 rotates.

An AC voltage having a DC component from the power supply 51 is applied to the developing sleeve 41.
A strong oscillating electric field is formed in the gap between the photosensitive drum 10 and the photosensitive drum 10. Due to the strong oscillating electric field, the toner T flies away from the carrier C, and a toner cloud is generated. As a result, a flight toward the latent image on the photosensitive drum 10 occurs, and a toner image is formed on the photosensitive drum 10.

Incidentally, in the contact type development, the layer thickness of the developer having the toner of the present invention is 0.1 to 0.1 in the development area.
It is preferably 8 mm, particularly preferably 0.4 to 5 mm.
The gap between the photosensitive drum and the developer sleeve is 0.1 mm.
It is preferably from 15 to 7 mm, particularly preferably from 0.2 to 4 mm.

In the non-contact developing system, the developer layer formed on the developer sleeve does not come into contact with the surface of the photosensitive drum. In order to constitute this developing system, the developer layer is thin. It is preferably formed of a layer. According to this method, a developer layer having a thickness of 20 to 500 μm is formed in a development area on a developing sleeve surface, and a gap between the photoconductor and the developer sleeve surface is larger than the developer layer.

This thin layer is formed by a magnetic blade using a magnetic force or a method of pressing a developer layer regulating rod against the surface of a developer carrier. Furthermore, there is a method in which a urethane blade, a phosphor bronze plate or the like is brought into contact with the surface of the developer carrier to regulate the developer layer. The pressing force of the pressing regulating member is 1 to 15
gf / mm is preferred. If the pressing force is small, the conveyance is likely to be unstable due to insufficient regulation force.
When the pressing force is large, the stress on the developer becomes large, so that the durability of the developer tends to decrease. A preferred range is 3 to 10 gf / mm. The gap between the developer carrier and the surface of the photoconductor needs to be larger than the developer layer. Further, when a developing bias is applied at the time of development, either a method of applying only a DC component or a method of applying an AC bias may be used.

The diameter of the developer sleeve is 1
Those having a thickness of 0 to 40 mm are preferred. When the diameter is small, the mixing of the developer is insufficient, and it is difficult to ensure sufficient mixing to give sufficient charge to the toner. When the diameter is large, the centrifugal force on the developer becomes large. , The problem of toner scattering is likely to occur.

FIG. 2 is a sectional view showing an example of an image forming apparatus used in the image forming method of the present invention. In this figure, 10 is a photosensitive drum as an image forming body, 20 is a scorotron charger as charging means, 25 is an image reading unit,
30 is an image writing unit using a laser beam as an exposure unit, 40A, 40B, 40C and 40D are developing devices shown in FIG. 1 containing two-component developers of different colors, respectively, and 60 is a first paper feed roller 61 and Second paper feed roller 62
, A transfer corona charger 70 as a transfer unit, 75 a corona charger for separation as a separation unit, 80
Denotes a conveying unit, 85 denotes a fixing unit, 90 denotes a cleaning device having a cleaning blade 91, and 95 denotes a pre-charging exposure lamp. Arrows in the drawing indicate the rotation direction of the photosensitive drum 10.

The image forming method according to the present invention will be described with reference to FIG. This is a multicolor image forming process. The basic operation is as follows. First, a copy start command is sent from an operation unit (not shown) to a control unit (not shown), and the photosensitive drum 10 starts rotating. As the photosensitive drum 10 rotates, its peripheral surface is uniformly charged by the scorotron charger 20. In the image reading section 25, optical information from the document is converted into an electric signal, and the electric signal is subjected to image processing,
It is input to the image writing unit 30. The charged photosensitive drum 10 is irradiated with a laser beam from the image writing unit 30 to form a latent image on the photosensitive drum 10. The latent image on the photosensitive drum 10 is developed by any of the developing devices 40A, 40B, 40C and 40D, and a toner image is formed on the photosensitive drum 10.

Photosensitive drum 1 on which toner image is formed
0 is uniformly charged again by the scorotron charger 20 and is irradiated with a laser beam by the image writing section 30 to form the next latent image. The latent images on the photosensitive drum 10 are stored in the developing devices 40A, 40B, 40C.
Or 40D, and the next toner image is superimposed on the photosensitive drum 10.

In this embodiment, the above-described latent image forming process
The development process is repeated four times, and four color toner images are superimposed on the photosensitive drum 10.

The paper feed unit 60 stores recording paper as a transfer material, and includes a first paper feed roller 61 and a second paper feed roller 6.
2, the toner image is sent to the transfer corona charger 70 in synchronization with the toner image superimposed on the photosensitive drum 10.
The toner image superimposed on the photosensitive drum 10 is transferred onto recording paper (recording material) by the corona charger 70 for transfer, and the recording paper is separated from the photosensitive drum 10 by a corona charger 75 for separation. Is done. The recording paper on which the toner image has been transferred is conveyed to a fixing unit 85 via a conveying unit 80,
After being fused and pressurized and fixed, it is discharged out of the apparatus.

On the other hand, the toner remaining on the photosensitive drum 10 without being transferred onto the recording paper is cleaned by a cleaning blade 9 which is pressed onto the photosensitive drum 10 in a timely manner.
1 is scraped off by a cleaning device 90 having
After the residual potential is removed by the pre-charging exposure lamp 95,
Enter the next image forming process.

Here, the order of superimposing the yellow, magenta, cyan, and black color images formed on the surface of the photoreceptor may be any order, but at least the second and subsequent developments must be performed by non-contact development.

[0130]

EXAMPLES Examples of the present invention will be described below, but the present invention is not limited to these examples.

Example 1 << Production of Non-Spherical Particles >> Production Example 1 of Non-Spherical Particles "Preparation of Colorant Dispersion Liquid 1"
0.90 kg of Adeka Hope LS-90 (manufactured by Asahi Denka Co., Ltd., sodium n-dodecyl sulfate) and 10.0 l of pure water are added and dissolved by stirring. To this solution, stir the Legal 330R under stirring.
(Carbon black manufactured by Cabot Corporation) 1.20 kg is gradually added, and after the addition, the mixture is stirred well for 1 hour. Next, continuous dispersion was performed for 20 hours using a medium type disperser (sand grinder).

After the 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. Further, the solid content concentration of the above-mentioned dispersion liquid measured by a gravimetric method by standing drying was 16.6 w / w%. This dispersion is referred to as “colorant dispersion 1”.

[Preparation of Latex-A] Into a 10 l stainless steel pot, 0.55 kg of sodium dodecylbenzenesulfonate (Kanto Chemical Co., Ltd., deer grade 1) was added, and 4.0 l of ion-exchanged water was added, followed by stirring at room temperature to dissolve. . this,
This is referred to as an anionic surfactant solution A.

In a 10 l stainless steel pot, 0.14 kg of Newcol 565C (manufactured by Nippon Emulsion Co., Ltd.) 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 (Kanto Chemical Co., Ltd., special grade) is placed in a 20 l enamel pot, 12.0 l of ion-exchanged water is added, and the mixture is stirred and dissolved at room temperature. this,
Called initiator solution C.

A 100-liter GL (glass-lined) reactor equipped with a temperature sensor, a cooling pipe, and a nitrogen introducing device was charged with W.
AX emulsion (polypropylene having a number average molecular weight of 3000 is heated to a melting point or higher to be dispersed and emulsified: number average primary particle diameter = 120 nm / solid content =
(29.9%) 3.41 kg and anionic surfactant solution A
And nonionic surfactant solution B, and stirring is started. Next, 44.0 l of ion-exchanged water is added.

Heating is started, and when the liquid temperature reaches 75 ° C., an 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.
A solution obtained by previously mixing 4 kg and 548 g of t-dodecyl mercaptan was mixed with a liquid sending pump equipped with a quantitative meter for 120 minutes.
(The average addition rate of all polymerizable monomers is 0.83% by weight / minute).

Further, the liquid temperature was raised to 80 ° C. ± 1 ° C.
Heating and stirring were performed for 6 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 the latex was filtered.
A.

The glass transition temperature of the resin particles in latex-A is 57 ° C., the softening point is 121 ° C., and the molecular weight distribution is as follows: weight average molecular weight = 12.7 million, weight average particle diameter is 12
It was 0 nm.

"Preparation of Latex-B" New 10 l
In a stainless steel pot, add 0.55 kg of sodium dodecylbenzenesulfonate (Kanto Chemical Co., Ltd., deer first grade)
4.0 I 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) is placed in a 10 l stainless steel pot, 4.0 l of ion-exchanged 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 (Kanto Chemical Co., Ltd., special grade) is added, 12.0 l of ion-exchanged water is added, and the mixture is stirred and dissolved at room temperature. this,
Called initiator solution F.

A WAX emulsion (polypropylene having a number average molecular weight of 3000) was heated to a melting point or higher and dispersed in a 100-liter GL reactor (a stirring blade was a Faudler blade) equipped with a temperature sensor, a cooling pipe, a nitrogen introducing device, and a comb baffle. And emulsified: number average primary particle size = 12
(0 nm / solids concentration 29.9%), 3.41 kg, anionic surfactant solution D and nonionic surfactant solution E are added, and stirring is started. Next, 44.0 liters of ion-exchanged water
Input.

Heating is started, and when the liquid temperature reaches 70 ° C., an 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 preliminarily mixed with 0. 02 g (the average addition rate of all the polymerizable monomers: 1.67 wt).
% / Min).

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 to 80 ° C.
The temperature was raised to ± 2 ° C., and the mixture was heated and stirred for 12 hours.

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

The resin particles in Latex-B had a glass transition temperature of 58 ° C., a softening point of 132 ° C., and a molecular weight distribution of 245,000.

[Preparation of Non-Spherical Particles 1] 5.36 kg of sodium chloride (1st grade, manufactured by Wako Pure Chemical Industries, Ltd.) as a salting-out agent and 20.0 l of ion-exchanged water are put into a 35 l stainless steel pot and stirred and dissolved. This is designated as sodium chloride solution G.

1.00 g of FC-170C (Nonionic surfactant, manufactured by Sumitomo 3M) is placed in a 2 liter glass beaker, and 1.00 liter of ion-exchanged water is added to dissolve with stirring.
This is designated as nonionic surfactant solution H.

The latex-A = 2 prepared above was placed in a 100-liter SUS reaction vessel equipped with a temperature sensor, a cooling pipe, a nitrogen introduction device, and a comb baffle (the stirring blade was an anchor blade).
0.0 kg, latex-B = 5.2 kg, colorant dispersion 1 = 0.4 kg, and ion-exchanged water 20.0 kg are added and stirred. Then, the mixture was heated to 40 ° C., and sodium chloride solution G and isopropanol (Kanto Chemical Co., Ltd., deer first grade)
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 lower and the stirring is stopped. Aperture 45
The solution is filtered through a sieve of μm, and this filtrate is used as an association liquid.

Next, non-spherical particles in the form of a wet cake were filtered from the association liquid using a Nutsche. afterwards,
It 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.

The non-spherical particles obtained as described above are referred to as “non-spherical particles 1”.

The molecular weight of the resin particles was as follows: weight average molecular weight = 550,000, softening point = 125 ° C., glass transition temperature = 57.
° C.

Production Example 2 of Non-Spherical Particles In Production Example 1 of non-spherical particles, the legal 330R
(Carbon black manufactured by Cabot Corporation) instead of C.I.
I. Pigment Red 122 was used in the same manner to obtain the colored particles of the present invention. The obtained colorant dispersion is referred to as “colorant dispersion 2”, and the non-spherical particles are referred to as “non-spherical particles 2”. The dispersion diameter of the colorant particles is 16
It was 0 nm.

Production Example 3 of Non-Spherical Particles In Production Example 1 of non-spherical particles, the legal 330R
(Carbon black manufactured by Cabot Corporation) instead of C.I.
I. Pigment Yellow 17 was used in the same manner as above to obtain colored particles of the present invention. The obtained colorant dispersion is referred to as “colorant dispersion 3”, and the non-spherical particles are referred to as “non-spherical particles 3”. The dispersion diameter of the colorant particles is 13
It was 0 nm.

Production Example 4 of Non-Spherical Particles In Production Example 1 of non-spherical particles, the legal 330R
(Carbon black manufactured by Cabot Corporation) instead of C.I.
I. Pigment Blue 15: 3 was used in the same manner as above to obtain the colored particles of the present invention. The obtained colorant dispersion is referred to as “colorant dispersion 4”, and the non-spherical particles are referred to as “non-spherical particles 4”. The dispersion diameter of the colorant particles is 9
It was 0 nm.

Production Example 5 of Non-Spherical Particles In Production Example 1 of non-spherical particles, the average addition rate of all polymerizable monomers in the production of latex-A was set at 1.
26% by weight (the resin in the obtained latex had a weight average molecular weight of 126,000, a softening point of 120 ° C, a glass transition temperature of 56 ° C, and a weight average particle size of 100 nm).
The average addition rate of all polymerizable monomers in Latex-B was 0.75% by weight per minute (the resin in the obtained latex had a weight average molecular weight of 305,000, a softening point of 133 ° C,
Glass transition temperature = 59 ° C and weight average particle size = 110 nm. ) To obtain colored particles of the present invention in the same manner. The non-spherical particles obtained here are referred to as “non-spherical particles 5”.

The obtained “non-spherical particles 5” had a weight average molecular weight of 59,000, a softening point of 126 ° C., and a glass transition temperature of
57 ° C.

Production Example 6 of Non-Spherical Particles In Production Example 1 of non-spherical particles, the average addition rate of all polymerizable monomers in the production of latex-A was set at 2.
73% by weight (the resin in the obtained latex had a weight-average molecular weight of 1.060,000, a softening point of 119 ° C, a glass transition temperature of 56 ° C, and a weight-average particle size of 102 nm).
The average addition rate of all polymerizable monomers in latex-B was 1.59% by weight per minute (the resin in the obtained latex had a weight average molecular weight of 301,000, a softening point of 129 ° C,
Glass transition temperature = 56 ° C., weight average particle size = 106 nm. ) To obtain colored particles of the present invention in the same manner. The non-spherical particles obtained here are referred to as “non-spherical particles 6”. The obtained “non-spherical particles 6” had a weight average molecular weight of 56,000, a softening point of 127 ° C, and a glass transition temperature of 57 ° C.

Production Example 7 of Non-Spherical Particles In Production Example 1 of non-spherical particles, the average addition rate of all polymerizable monomers in the production of latex-A was set at 1.
83% by weight (the resin in the obtained latex had a weight average molecular weight of 131,000, a softening point of 120 ° C, a glass transition temperature of 56 ° C, and a weight average particle size of 100 nm).
The average addition rate of all polymerizable monomers in Latex-B was 2.75% by weight per minute (the resin in the obtained latex had a weight average molecular weight of 296,000, a softening point of 129 ° C,
Glass transition temperature = 57 ° C., weight average particle size = 100 nm. ) To obtain colored particles of the present invention in the same manner. The non-spherical particles obtained here are referred to as “non-spherical particles 7”.

The obtained “non-spherical particles 7” had a weight average molecular weight of 56,000, a softening point of 127 ° C., and a glass transition temperature of
57 ° C.

Production Example 8 of Non-Spherical Particles In Production Example 1 of non-spherical particles, the average addition rate of all the polymerizable monomers in the production of latex-A was set at 0.1 per minute.
17% by weight (the resin in the obtained latex had a weight-average molecular weight of 261,000, a softening point of 121 ° C, a glass transition temperature of 56 ° C, and a weight-average particle size of 105 nm).
The average addition rate of all polymerizable monomers in Latex-B was 0.12% by weight per minute (the resin in the obtained latex had a weight average molecular weight of 312,000, a softening point of 133 ° C,
Glass transition temperature = 59 ° C., weight average particle size = 100 nm. ) To obtain colored particles of the present invention in the same manner. The non-spherical particles obtained here are referred to as “non-spherical particles 8”.

The obtained “non-spherical particles 8” had a weight average molecular weight of 61,000, a softening point of 129 ° C., and a glass transition temperature of
57 ° C.

Production Example 9 of Non-Spherical Particles In Production Example 1 of non-spherical particles, the average addition rate of all the polymerizable monomers in the production of latex-A was set at 4.
21% by weight (the resin in the obtained latex had a weight average molecular weight of 101,000, a softening point of 116 ° C, a glass transition temperature of 53 ° C, and a weight average particle size of 100 nm).
The average addition rate of all polymerizable monomers in Latex-B was 4.83% by weight per minute (the resin in the obtained latex had a weight average molecular weight of 262,000, a softening point of 128 ° C,
Glass transition temperature = 59 ° C., weight average particle size = 100 nm. ) To obtain colored particles of the present invention in the same manner. The non-spherical particles obtained here are referred to as “non-spherical particles 9”.

The obtained “non-spherical particles 9” had a weight average molecular weight of 59,000, a softening point of 128 ° C., and a glass transition temperature of
57 ° C.

Production Example 10 of Non-Spherical Particles In Production Example 1 of non-spherical particles, the polymerizable monomer of latex-A was styrene = 11.2 kg, butyl acrylate = 2.64 kg, and methacrylic acid = 2. Resin particles were obtained in the same manner except that the weight was changed to 50 kg. This is designated as Latex-A. In addition, the glass transition temperature of the resin particles in the latex-A was 56 ° C, the softening point was 119 ° C, the molecular weight distribution was weight average molecular weight = 131,000, and the weight average particle size was 120 nm.

Then, a latex was prepared according to Example 1.
Using A and latex-B, colored particles of the present invention were obtained. The non-spherical particles obtained here are referred to as “non-spherical particles 10”.

The obtained “non-spherical particles 10” had a weight average molecular weight of 59,000, a softening point of 127 ° C., and a glass transition temperature of 57 ° C.

Production Example 11 of Non-Spherical Particles In Production Example 1 of non-spherical particles, the polymerizable monomer of latex B was 13.25 kg of styrene, 3.21 kg of butyl acrylate, and 0.21 kg of acrylic acid. Resin particles were obtained in the same manner except that the weight was changed to 75 kg. This is designated as Latex-B. In addition, the glass transition temperature of the resin particles in the latex-B was 55 ° C, the softening point was 135 ° C, the molecular weight distribution was weight average molecular weight = 231,000, and the weight average particle size was 110 nm.

Then, a latex was prepared in the same manner as in Example 1.
Using A and latex-B, colored particles of the present invention were obtained. The non-spherical particles obtained here are referred to as “non-spherical particles 11”.

The obtained “non-spherical particles 11” had a weight average molecular weight of 56,000, a softening point of 128 ° C., and a glass transition temperature of 57 ° C.

Production Example 12 of Non-Spherical Particles In Production Example 1 of non-spherical particles, the polymerizable monomer of latex-A was styrene = 10.20 kg, butyl acrylate = 1.21 kg, and acrylic acid = 0.21 kg. 62 kg, and the polymerizable monomer of latex-B was changed to styrene = 1.
Resin particles were obtained in the same manner except that 1.31 kg, butyl acrylate = 0.82 kg, and acrylic acid = 0.45 kg were changed. These are designated as Latex-A and Latex-B. And The glass transition temperature of the resin particles in the latex-A was 54 ° C, the softening point was 124 ° C,
The molecular weight distribution was such that the weight average molecular weight was 51,000, the weight average particle size was 110 nm, the glass transition temperature of the resin particles in latex-B was 56 ° C, the softening point was 137 ° C, and the molecular weight distribution was the weight average molecular weight. = 191,000, and the weight average particle size was 110 nm. Subsequently, the colored particles of the present invention were obtained using latex-A and latex-B according to Example 1. The non-spherical particles obtained here are referred to as “non-spherical particles 12”.

The obtained “non-spherical particles 12” had a weight average molecular weight of 53,000, a softening point of 126 ° C., and a glass transition temperature of 55 ° C.

Production Example 13 of Non-Spherical Particles Resin particles were prepared in the same manner as in Production Example 1 of non-spherical particles except that the amount of t-dodecyl mercaptan used in the production of latex-A was changed to 120 g. This is designated as Latex-C. The resin particles have a glass transition temperature of 5
6 ° C., softening point was 128 ° C., molecular weight distribution was weight average molecular weight = 1260,000, and weight average particle size was 110 nm.
Except that only this latex-C was used, non-spherical particles were obtained using the same conditions as in the salting out / association of Production Example 1 for non-spherical particles. The non-spherical particles obtained here are referred to as “non-spherical particles 13”.

The obtained “non-spherical particles 13” had a weight average molecular weight of 126,000, a softening point of 128 ° C., and a glass transition temperature of 56 ° C.

Comparative Non-Spherical Particle Production Example 1 In the non-spherical particle production example 1, the average addition rate of all the polymerizable monomers in the production of the latex-A was 0.1 minute per minute.
Colored particles for comparison were obtained in the same manner except that the average addition rate of all polymerizable monomers in Latex-B was 0.04% by weight per minute. The obtained non-spherical particles are referred to as “non-spherical particles for comparison 1”. The latex obtained in place of latex-A is referred to as “comparison latex-A”, and the latex obtained in place of latex-B is referred to as “comparison latex-B”. The glass transition temperature of the resin particles in “Comparative Latex-A” was 55 ° C., the softening point was 122 ° C., and the molecular weight distribution was
Weight average molecular weight = 14,000, weight average particle size 110n
m, the glass transition temperature of the resin particles in “Comparative Latex-B” was 57 ° C., the softening point was 132 ° C., and the molecular weight distribution was weight average molecular weight = 223,000 and weight average particle size was 1
It was 10 nm. The “non-spherical particles for comparison 1” has a glass transition temperature of 56 ° C., a softening point of 127 ° C., a molecular weight distribution of weight average molecular weight = 56,000, and a volume average particle size of 6.6.
It was 93 μm.

Comparative Non-Spherical Particle Production Example 2 In the non-spherical particle production example 1, the average addition rate of all the polymerizable monomers in the production of the latex-A was 5.
Colored particles for comparison were obtained in the same manner except that 21% by weight and the average addition rate of all polymerizable monomers in Latex-B were 5.64% by weight per minute. The obtained non-spherical particles are referred to as “non-spherical particles for comparison 2”. The latex obtained in place of latex-A is referred to as “comparison latex-A”, and the latex obtained in place of latex-B is referred to as “comparison latex-B”. The glass transition temperature of the resin particles in “Comparative Latex-A” was 56 ° C., the softening point was 123 ° C., and the molecular weight distribution was
Weight average molecular weight = 131,000, weight average particle size is 110n
m, the glass transition temperature of the resin particles in “Comparative Latex-B” was 57 ° C., the softening point was 132 ° C., and the molecular weight distribution was weight-average molecular weight = 13,000, and the weight-average particle size was 1
It was 10 nm. The “non-spherical particles for comparison 2” had a glass transition temperature of 55 ° C., a softening point of 126 ° C., a molecular weight distribution of weight average molecular weight = 275,000, and a volume average particle size of 7.82 μm.

Comparative Non-Spherical Particle Production Example 3 In Production Example 1 of non-spherical particles, the addition of all polymerizable monomers in the production of latex-A was not carried out successively but all at once (average addition). The addition rate is equivalent to 100% by weight per minute), and all the polymerizable monomers in Latex-B are not added sequentially but also collectively (the average addition rate is equivalent to 100% by weight per minute). Other than the above, colored particles for comparison were obtained in the same manner. The non-spherical particles obtained here are referred to as “non-spherical particles for comparison 3”. In addition, latex-A
And the latex obtained in place of Latex-B is referred to as "Comparative Latex-B". The glass transition temperature of the resin particles in “Comparative Latex-A” was 56 ° C., the softening point was 123 ° C., and the molecular weight distribution was weight average molecular weight = 15,000, and volume average particle diameter was 110 nm.
The glass transition temperature of the resin particles in “Comparative Latex-B” was 57 ° C., the softening point was 133 ° C., the molecular weight distribution was weight average molecular weight = 276,000, and the weight average particle size was 110 nm. The “non-spherical particles for comparison 3” had a glass transition temperature of 57 ° C., a softening point of 125 ° C., a molecular weight distribution of 53,000, and a volume average particle size of 9.51 μm.

<< Evaluation of Particle Size and Shape >> For the above “non-spherical particles 1” to “non-spherical particles 13” and “comparative non-spherical particles 1” to “comparative non-spherical particles 3”, Evaluation was performed on the particle size and shape. For the shape, using a photo magnified 1000 times with a scanning electron microscope,
The uniformity of the shape was visually evaluated.

Regarding the particle size, the volume average particle size D ₅₀ and the particle size distribution CV were measured using a laser diffraction type particle size measuring device / SLAD1100 manufactured by Shimadzu Corporation. The particle size distribution CV is the standard deviation (D ₅₀ ) / D ₅₀ , and a smaller value indicates a narrower particle size distribution.

[0184]

[Table 1]

<< Print Evaluation >> The above “non-spherical particles 1” to
"Non-spherical particles 13" and "Non-spherical particles 1 for comparison"
1% by weight of hydrophobic silica (primary average particle diameter = 12 nm) was added to “Comparative non-spherical particles 3” to obtain a toner. These toners are referred to as “toner 1” to “toner 13” and “comparative toner 1” to “comparative toner 3”, respectively.

Further, a developer having a toner concentration of 6% was prepared by mixing these toners and a ferrite carrier coated with a styrene acrylic resin and having a volume average particle diameter of 45 μm, and used for evaluation of printing. These developers are referred to as “developer 1” to “developer 13” and “comparative developer 1” to “comparative developer 3”, respectively, corresponding to the toner.

Evaluation (Non-Contact Developing Method) In the evaluation, a Konica color copier 9028 was modified and used. The conditions are as shown below. A laminated organic photoreceptor was used as the photoreceptor.

Photoreceptor surface potential = -550 V DC bias = -250 V AC bias = Vp-p: -50 to -450 V Alternating electric field frequency = 1800 Hz Dsd = 300 μm Pressing force = 10 gf / mm Pressing rod = SUS416 (magnetic stainless steel) Made) /
Diameter 3 mm Developer layer thickness = 150 μm Developing sleeve = 20 mm As a fixing method, a method of using a hot roll fixing method and cleaning the untransferred toner remaining on the photoreceptor by a blade cleaning method was adopted.

The transfer paper used was a paper having a continuous weight of 55 kg, and an image was formed in the vertical direction. The image formation was performed in a normal temperature and normal humidity environment (25 ° C./55% RH). As the evaluation items, the sharpness of the image due to the reproducibility of the fine line was evaluated. This evaluation is based on the number of fine lines that can be reproduced per 1 mm, and was evaluated for both vertical and horizontal thin lines. The images were compared with a 10-fold loupe, and the maximum number per 1 mm that could be determined in a state where lines were formed continuously without intermittent lines was compared. The results are shown below.

In addition, by using an image having a 5% pixel rate, 1
The printing of 100,000 sheets was performed in a normal temperature and normal humidity environment, and the same evaluation was performed for the image after 100,000 sheets. Further, as the odor evaluation, the presence or absence of odor at the fixing site was continued by sensory evaluation. With sensory evaluation, using 10 observers, perform continuous printing of 1000 sheets in a room without air flow,
The evaluation was based on how many people felt the odor. The results are shown below.

[0191]

[Table 2]

Evaluation (Contact Developing Method) A digital copying machine 7050 manufactured by Konica was remodeled and a real image evaluation was performed. The conditions are as shown below. A laminated organic photoreceptor was used as the photoreceptor.

Photoconductor surface potential = −700 V DC bias = −500 V Dsd = 600 μm Developer layer regulation = Magnetic H-Cut method Developer layer thickness = 700 μm Developing sleeve diameter = 40 mm φ As a fixing method, hot roll fixing is used. A method of cleaning the untransferred toner remaining on the photoreceptor by a blade cleaning method was employed.

The transfer paper used was a paper having a continuous weight of 55 kg, and an image was formed in the vertical direction. The image formation was performed in a normal temperature and normal humidity environment (25 ° C./55% RH). As the evaluation items, the sharpness of the image due to the reproducibility of the fine line was evaluated. This evaluation is based on the number of fine lines that can be reproduced per 1 mm, and was evaluated for both vertical and horizontal thin lines. The images were compared with a 10-fold loupe, and the maximum number per 1 mm that could be determined in a state where lines were formed continuously without intermittent lines was compared. The results are shown below.

In addition, by using an image having a 5% pixel rate, 1
The printing of 100,000 sheets was performed in a normal temperature and normal humidity environment, and the same evaluation was performed for the image after 100,000 sheets. Further, as the odor evaluation, the presence or absence of odor at the fixing site was continued by sensory evaluation. With sensory evaluation, using 10 observers, perform continuous printing of 1000 sheets in a room without air flow,
The evaluation was based on how many people felt the odor. The results are shown below.

[0196]

[Table 3]

As shown in the above results, the toner of the present invention is excellent in transferability and can maintain high image quality for a long period of time. Further, it is understood that the toner does not generate an unpleasant odor in the fixing portion and does not cause a problem in use.

According to the present invention, at the time of association, polymerized toner particles having a uniform particle size and surface state can be obtained, so that good transferability can be obtained, and as a result, high quality electrophotographic images can be obtained.

[0199]

According to the present invention, there is provided a toner for developing an electrostatic latent image, which has good transferability to an image support and can maintain high image quality for a long period of time, and a method for producing the same. And an image forming method using the above toner.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating an example of a developing device (developing device) used in the image forming method of the present invention.

FIG. 2 is a cross-sectional view illustrating an example of an image forming apparatus used in the image forming method of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 10 photoconductor drum (image forming body) 11 conductive substrate 12 photosensitive layer 20 scorotron charger 25 image reading unit 30 image writing unit 40A, 40B, 40C, 40D developing device (developing device) 41 developing sleeve (developer conveying member) 42 magnet body 45 supply roller 46 regulating rod 47 scraper 48 stirring roller 49 casing 50 two-component developer 51 power supply 60 paper supply unit 61 first paper supply roller 62 second paper supply roller 70 transfer corona charger 75 separation corona charger Container 80 Conveying Unit 85 Fixing Unit 90 Cleaning Device 91 Cleaning Blade 95 Pre-Charging Exposure Lamp

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Asao Matsushima 2970 Ishikawacho, Hachioji-shi, Tokyo Konica Corporation F-term (reference) 2H005 AA01 AB06 CA04 CA30 DA07 EA07 2H077 AA20 AB01 AD06 AD13 AD17 AD24 AD32 AD36 EA03 EA14 EA16 FA01 GA13

Claims (8)

[Claims] 1. An electrostatic latent image developing toner in which at least resin particles and colorant particles are salted out and fused, wherein the resin particles are polymerized in an aqueous solution in which a polymerization initiator is dissolved. Average addition rate of 0.1% of all polymerizable monomers per minute
A toner for developing an electrostatic latent image, wherein the resin particles are polymerized by being added at a weight percentage of 5.0 to 5.0 weight%. 2. The method according to claim 1, wherein the average rate of addition of the polymerizable monomer is from 0.3% by weight to 3.0% by weight of the total polymerizable monomer per minute. Charge latent image developing toner. 3. A method for producing a toner for developing an electrostatic latent image having at least resin particles and colorant particles, wherein an average addition rate of a polymerizable monomer to an aqueous solution in which a polymerization initiator is dissolved is increased per minute. 0.1% by weight to 5.0% by weight of the total polymerizable monomer.
A method for producing a toner for developing an electrostatic latent image, comprising salting out and fusing the resin particles and the colorant particles which have been added and polymerized by weight percent. 4. The toner for developing an electrostatic latent image according to claim 3, wherein the average addition rate is from 0.3% by weight to 3.0% by weight of the total polymerizable monomer per minute. Manufacturing method. 5. An aqueous solution in which a polymerization initiator is dissolved in a developer for electrostatic latent image development in which at least resin particles and colorant particles are salted out and fused, and a developer having magnetic particles. A resin particle obtained by adding a polymerizable monomer therein at an average addition rate of 0.1% by weight to 5.0% by weight of the total polymerizable monomer per minute and polymerizing. Agent. 6. The developer according to claim 5, wherein said average addition rate is from 0.3% by weight to 3.0% by weight of the total polymerizable monomer per minute. 7. The latent image formed on the electrostatic latent image forming body is developed with a developer having at least a toner for developing an electrostatic latent image, and then transferred to an image support and thermally fixed to form an image. In the obtained image forming method, the toner is a toner for developing an electrostatic latent image in which at least resin particles and colorant particles are salted out and fused, and the resin particles are in an aqueous solution in which a polymerization initiator is dissolved. Particles obtained by adding a polymerizable monomer at an average addition rate of 0.1% by weight to 5.0% by weight of the total polymerizable monomer per minute, and polymerizing the polymerizable monomer. An image forming method, comprising: cleaning an electrostatic latent image developing toner remaining on the toner. 8. The image forming method according to claim 7, wherein the average addition rate is from 0.3% by weight to 3.0% by weight of the total polymerizable monomer per minute.