JPH09296051A - Production of polymer particle, toner for developing electrostatic latent image, and method for forming image - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a process for producing polymer particles having a chargeability which is independent of the environmental conditions, not by the conventional method of adding a charge regulator but by the so-called polymer toner production method such as emulsion polymn. or suspension polymn. wherein a toner having a charge-regulation group on the surface thereof and also having a stable charging characteristics is used, a toner for developing an electrostatic latent image, and a method for forming images. SOLUTION: Polymer particles are produced by associating two or more fine particles of a polymer emulsion dispersed in water. In the association, an organic solvent which is unlimitedly soluble in water and in which the fine polymer particles are insoluble is added and the association temp. is rapidly elevated from room temperature to a temperature 1 to 30 deg.C lower than the boiling point of the mixed solvent comprising the organic solvent and water and then elevated to near the boiling point of the mixed solvent at a rate lower than that in the preceding step.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for producing polymer particles, a toner for developing an electrostatic latent image and an image forming method.

[0002]

2. Description of the Related Art Conventionally, toners used for electrostatic latent image development such as electrophotography are generally composed of a thermoplastic resin containing a coloring agent (carbon black, magnetic powder, pigment, etc.), a charge control agent,
And other additives are melt-kneaded, and then pulverized and classified.

However, the above-described method of producing a toner by pulverization has various disadvantages. Firstly, a polymerization apparatus for resin production, an apparatus for kneading, an apparatus associated with many steps such as a crusher, a classifier, etc. are required, and the number of steps is large and the energy consumption is large, which increases the cost. It is the cause. Particularly in recent years, due to the improvement in image quality, the tendency of smaller particle diameter and sharper particle size distribution has been strengthened, resulting in higher cost. Secondly, it is extremely difficult to uniformly disperse the colorant and other additives in the resin in the kneading step, and therefore the toner produced by this method has poor dispersion of the colorant, the charge control agent and the like. In addition, the charging characteristics of each particle are different, which leads to a decrease in resolution.

In order to improve various drawbacks of the toner obtained by the pulverization method, a method for producing a so-called polymerized toner such as an emulsion polymerization method or a suspension polymerization method has been proposed (Japanese Patent Publication No. 36-10231). Japanese Patent Publication 47-5183
No. 05, Japanese Patent Publication No. 51-14895).

However, polymerized toner also has various problems. For example, the so-called suspension polymerization method has a problem that the particles become spherical particles, the adhesion to the photoconductor increases, and cleaning becomes difficult. Therefore, JP-A-5-11
As disclosed in Japanese Patent No. 5572, there is proposed a method of forming amorphous toner particles by associative fusion. However, when amorphization is performed, there is a problem in that the degree of irregularity is distributed depending on the manufacturing conditions, and as a result, it becomes difficult to make the particle size distribution uniform.

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to propose a method for producing a polymer toner having a uniform particle size distribution and a uniform charge amount in an associative polymer toner. is there. Still another object is to provide a toner prepared by these manufacturing methods and an image forming method.

[0007]

The object of the present invention can be achieved by adopting any of the following constitutions.

(1) In a method for producing polymer particles by associating a plurality of polymer particles obtained by emulsifying and dispersing in water, the polymer particles are infinitely dissolved in the association, and the polymer particles are not dissolved. The step of adding an organic solvent, the step of rapidly raising the association temperature from room temperature to a temperature 1 to 30 ° C. lower than the boiling point of the mixed solvent of the organic solvent and water, and then until near the boiling point of the mixed solvent, A method for producing polymer particles, comprising the step of raising the temperature at a slower rate than the step.

(2) A step of washing, filtering and drying the polymer particles is included after the step of raising the temperature to a temperature near the boiling point of the mixed solvent at a slower rate than the previous step. Method for producing polymer particles.

(3) The method for producing polymer particles as described in (1) or (2), wherein the polymer particles are a toner for developing an electrostatic latent image.

(4) A toner for developing an electrostatic latent image, which is produced by the method for producing a toner for developing an electrostatic latent image according to (2).

(5) The toner has a BET specific surface area of 5
The toner for developing an electrostatic latent image according to (4), characterized in that the toner has a content of -100 m ² / g.

(6) In an image forming method for exposing a latent electrostatic image formed on a photoreceptor to a toner image,
An image forming method using the electrostatic latent image developing toner of (4) or (5).

(7) In an image forming method for transferring a toner image formed on a photosensitive member to a transfer material, the electrostatic latent image developing toner of (4) or (5) is used to form an image. Method.

(8) In the image forming method, in which the toner image formed on the photoconductor is transferred onto a transfer material, and then the residual toner on the photoconductor is cleaned and removed.
Alternatively, an image forming method comprising using the electrostatic latent image developing toner of (5).

The present invention will be described in more detail by taking an electrostatic latent image developing toner as an example.

The polymerization method used in the present invention can be carried out by suspension polymerization or emulsion polymerization in the presence of additives such as colorants and release agents required for toners for developing electrostatic latent images. Is a method for producing polymer particles containing the colorant and the release agent. Particularly preferably, a method of synthesizing polymer fine particles by an emulsion polymerization method in an aqueous dispersion medium and then associating a plurality of them to obtain polymer particles having a desired particle diameter as a toner is a particle size distribution of the obtained toner and The controllability of the shape is easy, and according to the present invention, the aggregation of the individual polymer particles can be disintegrated without breaking them.

The details of the manufacturing method are as follows. First, in a polymerization step, a colorant treated with a surface modifier, if necessary, is dispersed in an aqueous solution having a surfactant dispersion concentration of CMC or more, and then the dispersion is performed. The liquid is diluted until the concentration of the surfactant becomes CMC or less, then the water-soluble radical polymerization initiator is dissolved in the dispersion, and a monomer is added to carry out aqueous precipitation polymerization to contain the colorant. This is a method for obtaining polymer fine particles. Then, as a meeting step, JP-A-5-11557
No. 2 method, that is, an aggregating agent having a concentration higher than the critical aggregation concentration of the polymer fine particle dispersion and an organic solvent that is infinitely soluble in water and does not dissolve the polymer fine particles are added, and a plurality of the polymer fine particles are added. Align and produce associated colored particles.

Incidentally, as a meeting method, various methods, for example, JP-A-60-220358 and JP-A-4-28446.
No. 1 etc. However, it is difficult to control the desired particle size and particle size distribution only with these methods. Therefore, the inventors of the present invention have completed the present invention as a result of intensive studies.

That is, the particles themselves can be sufficiently associated with each other only by adding an infinitely soluble solvent and heating, but the particle size distribution of the associated particles cannot be controlled and the particle size distribution is stabilized. Cannot be made uniform. As a factor that governs this distribution, we have found that the heat transfer rate is an important factor, and completed the present invention.

The present invention will be described below.

Specific examples of the organic solvent insoluble in water and insoluble in polymer fine particles include alcohol solvents such as methanol, ethanol, isopropanol, butanol, allyl alcohol, ethylene chlorohydrin, ethylene glycol, and the like. Glycerin can be mentioned. Isopropanol is particularly preferable.

In the step of adding the organic solvent, it is preferable to add the organic solvent at room temperature, that is, about 0 to 40 ° C. after forming the polymer fine particles. The ratio of the organic solvent to water in the mixed solvent is 1: 1 to 1: 1000, preferably 1: 4 to 1: 100.

In the step of rapidly raising the temperature, it is necessary to raise the temperature to 1 to 30 ° C. lower than the boiling point of the mixed solvent of the organic solvent and water, and more preferable to raise the temperature to 5 to 10 ° C. lower. In the step of rapidly raising the temperature, the rate of temperature increase is preferably 1.0 ° C./min or more, more preferably 1.5 ° C./min or more. It is considered that the upper limit of the temperature rising rate is not particularly limited from the viewpoint of achieving the object of the present invention, but from a practical viewpoint, it is 5.0 ° C./min or less, particularly preferably 4.0 ° C.
/ Min or less is preferable.

In the step of raising the temperature to near the boiling point at a slow rate, the temperature is raised at a rate of less than 1.0 ° C./min, preferably less than 0.5 ° C./min. It is considered that the lower limit of the temperature rising rate is not particularly limited in order to achieve the object of the present invention, but from the practical viewpoint, it is 0.05 ° C / mi.
n or more, preferably 0.1 ° C./min or more.

Further, the BET of the present invention is prepared by heat fusion at a temperature not lower than the glass transition temperature of the polymer itself formed.
It is possible to form a toner having a specific surface area.

The production apparatus used in the production method used in the production method of the present invention, the raw materials used, etc. will be described with reference to specific representative examples.

[Production Apparatus] (1) Stirring Kettle The shape of the reaction kettle at the time of association is not particularly limited, but an ordinary cylindrical or spherical reaction kettle is preferable.

(2) Stirring blade The shape of the stirring blade at the time of meeting is not particularly limited. Examples thereof include anchor blades, turbine blades, Faudler blades, Maxblend blades, paddle blades, helical ribbon blades, and bull margin blades.

[Monomer] As the polymerizable monomer, a hydrophobic monomer is used as an essential constituent component, and if necessary, a hydrophilic monomer and a crosslinkable monomer are used.

(1) Hydrophobic Monomer The hydrophobic monomer constituting the monomer component is not particularly limited, and conventionally known monomers can be used. In addition, one kind or a combination of two or more kinds can be used so as to satisfy required characteristics.

Specifically, α-methylene aliphatic carboxylic acid ester monomers such as vinyl aromatic monomers, acrylic acid ester monomers, and methacrylic acid ester monomers, and vinyl ester monomers. Monomer, vinyl ether monomer, monoolefin monomer, diolefin monomer,
Halogenated olefin monomers and the like can be used.

Examples of vinyl aromatic monomers include:
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 α-methylene aliphatic carboxylic acid ester type monomer include methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, phenyl acrylate,
Methyl methacrylate, ethyl methacrylate, butyl methacrylate, hexyl methacrylate, methacrylic acid-2-
Ethylhexyl, β-ethyl ethyl acrylate, γ
-Propyl aminoacrylate, stearyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate and the like.

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

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

Examples of the monoolefin type 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 and chloroprene.

(2) Hydrophilic monomer The hydrophilic monomer constituting the monomer component is not particularly limited, and conventionally known monomers can be used. In addition, one kind or a combination of two or more kinds can be used so as to satisfy required characteristics.

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, or a quaternary ammonium salt can be used. it can.

Examples of the carboxylic acid group-containing monomer include acrylic acid, methacrylic acid, fumaric acid, maleic acid, itaconic acid, cinnamic acid, maleic acid monobutyl ester, maleic acid monooctyl ester and the like.

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

Examples of amine compounds include dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, diethylaminoethyl acrylate, diethylaminoethyl methacrylate, 3-dimethylaminophenyl acrylate, 2-hydroxy-3-methacryloxypropyltrimethylammonium salt and the like. Is mentioned.

(3) Crosslinkable Monomer A crosslinkable monomer may be added to improve the characteristics of polymer particles. As crosslinkable monomers, divinylbenzene,
Divinylnaphthalene, divinyl ether, diethylene glycol methacrylate, ethylene glycol dimethacrylate, polyethylene glycol dimethacrylate,
Examples thereof include those having two or more unsaturated bonds such as diallyl phthalate.

The monomer according to the present invention comprises 8 hydrophobic monomers.
The hydrophilic monomer is appropriately selected in the range of 5 to 99.9% by weight and the hydrophilic monomer in the range of 0.1 to 15% by weight.

[Chain Transfer Agent] A commonly used chain transfer agent can be used for the purpose of adjusting the molecular weight.

The chain transfer agent is not particularly limited and, for example, mercaptans such as octyl mercaptan, dodecyl mercaptan and tert-dodecyl mercaptan are used.

[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) salt, etc.), Examples thereof include peroxide compounds.

Further, the above radical polymerization initiator can be used as a redox type 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 at least the minimum radical generation temperature of the polymerization initiator, but for example, a range of 50 ° C. to 80 ° 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] The surfactant is a sulfonate (sodium dodecylbenzenesulfonate, sodium arylalkyl polyethersulfonate, 3,3-).
Disulfone diphenyl urea-4,4-diazo-bis-amino-8-naphthol-6-sulfonate sodium, ortho-carboxybenzene-azo-dimethianiline,
2,2,5,5-tetramethyl-triphenylmethane-
4,4-diazo-bis-β-naphthol-6-sulfonate, etc.), sulfate ester salts (sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate, etc.), fatty acid salts (sodium oleate, sodium laurate, caprin) Acid sodium salt, sodium caprylate, sodium caproate, potassium stearate, calcium oleate, etc.) and the like.

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

(1) Inorganic Pigment As the inorganic pigment, conventionally known ones 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 pigment added is about 2 to about 20 parts, preferably about 3 to 15 parts, relative to the polymer.

(2) Organic Pigment As the organic pigment, conventionally known ones 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 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.

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 may be used alone or in combination of two or more as desired. The addition amount of the pigment is 2 to 20 parts with respect to the polymer, preferably 3 to 20 parts.
15 copies are selected.

(3) Surface Modifying Agent When a surface modifying agent for a colorant is used, a conventionally known one can be used. Specifically, a silane compound,
Titanium compounds and aluminum compounds can be preferably used.

As the silane compound, alkoxysilane such as methyltrimethoxysilane, phenyltrimethoxysilane, methylphenyldimethoxysilane, diphenyldimethoxysilane, silizane such as hexamethyldisilazane, γ-chloropropyltrimethoxysilane, vinyltrichlorosilane. , Vinyltrimethoxysilane, vinyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane,
γ-aminopropyltriethoxysilane, γ-ureidopropyltriethoxysilane, and the like.

As the titanium compound, for example, TTS, 9S, 38S, 41B, 46B, 55, 138, which is commercially available under the trade name "Planeact" manufactured by Ajinomoto Co., Inc.
S-1, 238S, etc., commercial products A-1 and B-
1, TOT, TST, TAA, TAT, TLA, TO
G, TBSTA, A-10, TBT, B-2, B-4,
B-7, B-10, TBSTA-400, TTS, TO
A-30, TSDMA, TTAB, TTOP and the like.

Examples of the aluminum compound include "Planeact AL-M" manufactured by Ajinomoto Co., Inc.

The concentration of these surface modifiers is 0.01 to 20% by weight, preferably 1 to 15% by weight, based on the colorant.

In addition, additives necessary when the polymer particles are used as a toner are contained, and typical examples thereof include a fixing improver and a charge control agent.

(4) Fixing Improver Known fixing improvers are used. Generally, a polyolefin type is used. For example, low molecular weight polyethylene, low molecular weight polypropylene, oxidized polyethylene and polypropylene, acid modified polyethylene and polypropylene, and the like are used.

(5) Charge Control Agent As the charge control agent, a known charge control agent is also used. However, when a monomer having a polar group on the polymer particle surface is copolymerized, it may not be necessary in some cases. As used herein, the polar group refers to a carboxyl group, a sulfonic acid group, an amino group, an ammonium base, or the like, which has a positive or negative charge.

Examples of the charge control agent include a nigrosine-based electron-donating dye having a positive charge, a metal salt of naphthenic acid or a higher fatty acid, an alkoxylated amine, a quaternary ammonium salt, an alkylamide, a metal complex, a pigment, and a fluorine-treated material. Examples include an activator and the like, an organic complex having an electron accepting property as a negative charge, chlorinated paraffin, chlorinated polyester, sulfonylamine of copper phthalocyanine, and the like.

[External Additive] In the present invention, when the polymer particles are washed and dried to prepare a toner for developing an electrostatic image, a fluidizing agent and a charge control agent are added in order to improve the fluidity and cohesiveness of the toner. In addition, it is usual to add various additives such as a lubricant.

(1) Inorganic Fine Particles As the inorganic fine particles, conventionally known ones can be used. Specifically, silica, titanium, alumina fine particles and the like can be preferably used.

As the silica fine particles, for example, commercially available products manufactured by Nippon Aerosil Co., Ltd. R-805, R-976, R-805
974, R-972, R-812, R-809, HVK-2150 and H-200 manufactured by Hoechst Co., Ltd., and commercial products TS-720, TS-530, TS manufactured by Cabot Co., Ltd.
-610, H-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.

(2) Organic Fine Particles For example, examples of the charge control agent include polyvinylidene fluoride, polystyrene powder, polymethylmethacrylate powder, and polyethylene fine particles.

(3) Lubricants Lubricants include, for example, cadmium, barium, nickel, cobalt, strontium, copper, magnesium, calcium salts of stearic acid, zinc oleate, zinc palmitate, zinc linoleate, zinc ricinoleate, capryl. Examples thereof include metal salts of higher fatty acids such as lead acid salt and lead caproate. These are added as needed.

Although the particle size of the toner of the present invention itself is arbitrary, a toner having a small particle size tends to exhibit the effect of the present invention. The volume average particle diameter is preferably 2 to 10 μm, particularly 3 to 9 μm.
m is preferable. This particle size can be controlled by the concentration of the flocculant, the amount of the organic solvent added, and the composition of the polymer itself.

The toner of the present invention is used as a one-component magnetic toner containing a magnetic substance, used as a two-component developer by mixing with a so-called carrier, and used as a non-magnetic toner alone. Are considered and any of them can be preferably used. In the present invention, this is preferably used as a two-component developer which is used as a mixture with a carrier.

As the carrier constituting the two-component developer, either an uncoated carrier composed only of magnetic material particles such as iron or ferrite, or a resin coated carrier in which the surface of the magnetic material particles is coated with resin or the like is used. Good. The average particle size of this carrier is 30 to 1 in terms of volume average particle size.
50 μm is preferred. The resin for coating is not particularly limited, and examples thereof include styrene-acrylic resin.

[Image Forming Method] The developing method in which the toner of the present invention can be used is not particularly limited. It can be suitably used in a contact development system or a non-contact development system. In particular, the toner of the present invention has a high charge rising property and is useful for a non-contact developing method. That is, in the non-contact developing method, since the change in the developing electric field is large, the minute change in the charge amount of the toner is large and affects the developing itself. However, since the toner of the present invention has a high charge rising property, the change in charge is small and a stable charge amount can be secured, so that a stable image can be formed over a long period even by the non-contact developing method. it can.

For contact type development, the layer thickness of the developer containing the toner of the present invention is 0.1 to 8 m in the developing area.
m, particularly preferably 0.4 to 5 mm. Also,
The gap between the photoconductor and the developer carrier is 0.15 to 7 mm,
In particular, it is preferably 0.2 to 4 mm.

In the non-contact type developing system, the developer layer formed on the developer carrying member does not come into contact with the photoconductor, and the developer layer is a thin layer in order to constitute this developing system. Is preferably formed. In this method, a developer layer having a thickness of 20 to 500 μm is formed in a development region on the surface of the developer carrier, and a gap between the photoconductor and the developer carrier has a larger gap than the developer layer. This thin layer is formed by a magnetic blade that uses magnetic force or a method of pressing a developer layer regulating rod against the surface of the developer carrier. further,
There is also 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 preferably from 1 to 15 gf / mm. When the pressing force is small, the conveyance is likely to be unstable because the regulating force is insufficient. On the other hand, when the pressing force is large, the stress on the developer is increased, and the durability of the developer is likely to be reduced. Particularly preferred range is 3 to 10 gf / mm
It is.

Further, when a developing bias is applied during development, either a system of applying only a DC component or a system of applying an AC bias may be used.

The size of the developer carrying member is 10 in diameter.
Those having a size of ４０40 mm are preferred. If the diameter is small, the mixing ability of the developer is insufficient, and it becomes difficult to give sufficient charge to the toner. If the diameter is large, the centrifugal force against the developer becomes large, and the problem of toner scattering occurs. Is likely to occur.

An example of the non-contact developing method will be described below with reference to FIG.

FIG. 1 is a schematic view of a developing section of a non-contact developing system which can be suitably used in the image forming method of the present invention. 1 is a photoconductor, 2 is a developer carrier, 3 is the toner of the present invention. The contained two-component developer, 4 is a developer layer regulating member, 5 is a developing region, 6 is a developer layer, and 7 is a power source for forming an alternating electric field.

The two-component developer containing the toner of the present invention is carried by the magnetic force on the developer carrier 2 having the magnet 2B therein, and is conveyed to the developing area 5 by the movement of the developing sleeve 2A. At the time of this conveyance, the developer layer 6 is regulated by the developer layer regulating member 4 in the developing region 5 to a layer of that thickness so as not to come into contact with the photoreceptor 1.

The minimum gap (Dsd) of the developing area 5 is the thickness of the developer layer 6 conveyed to that area (preferably 20 to 5).
00 μm), for example, about 100 to 1000 μm. The power source 7 for forming the alternating electric field is preferably an alternating current having a frequency of 1 to 10 kHz and a voltage of 1 to 3 kVp-p. The power supply 7 may have a configuration in which direct current is added in series to alternating current as necessary. 300 when adding DC voltage
~ 800V is preferred.

When the toner of the present invention is applied to a color image forming system, a system in which a monochromatic image is formed on a photosensitive member and sequentially transferred to an image support (this system is referred to as a sequential transfer system and is shown in FIG. 2). Alternatively, a method of developing a single color image on a photoconductor a plurality of times to form a color image and then collectively transferring the image to an image support (this is referred to as a batch transfer method and is shown in FIG. 3).
And the like.

The image forming method shown in FIGS. 2 and 3 will be described in detail below.

As the developer carrying member used in the present invention, as shown in FIG. 1, a developing device having a magnet 2B incorporated therein is used, and a developing sleeve 2A constituting the surface of the developer carrying member is used. As the material, aluminum, aluminum whose surface is oxidized, or stainless steel is used.

An example of the sequential transfer system shown in FIG. 2 will be described below.

11 is a charging electrode, 12 is yellow,
A developing unit including a developing device in which magenta, cyan, and black toners are respectively loaded, and is divided into four devices corresponding to four color toners. The basic configuration of these developing devices is shown in FIG.
It is the same as the schematic view of the developing unit shown in FIG. Reference numeral 14 is a photoconductor drum, 13 is a cleaning unit, 15 is a temporary holding toner image of a monochromatic color formed on the photoconductor drum, and a toner image of the next color is held thereon, and finally a desired toner image is finally held. A transfer drum that forms a multicolor image, 16 is a transport unit that transports a transfer material onto which the toner image on the transfer drum is transferred, 17 is provided inside the transfer drum 15, and corona discharge from inside causes transfer material. Is electrostatically adsorbed on the drum, 18 is a transfer electrode for sequentially transferring the toner image formed on the photoconductor 14 to the transfer drum, and 19 is for peeling the transfer material electrostatically adsorbed on the transfer drum 15. The peeling electrode 20 is a removing electrode for removing the electric charge remaining on the transfer drum after the transfer material is peeled off.

Electric charges are uniformly formed on the photosensitive drum 14 by the charging electrode 11, and thereafter, imagewise exposure (means not shown) is performed to form an electrostatic latent image. This electrostatic latent image is developed by a developing device that holds one color toner (for example, black toner) of the developing unit 12, and a one color toner image is formed on the photosensitive drum 14. On the other hand, the transfer material transferred onto the transfer drum 15 by the transfer unit 16 is the adsorption electrode 1
It is electrostatically adsorbed on the transfer drum by 7 and conveyed to the transfer section.

At the transfer portion, the toner image formed on the photosensitive drum 14 is transferred onto the conveyed transfer material. The toner remains on the photosensitive drum 14 after the transfer of the transfer image, and the remaining toner is cleaned by the cleaning unit 13 and used for the next process. When forming a multicolor image, toner images of other colors are formed by development according to a similar process and transferred one by one to the transfer drum 15. Eventually, a desired toner image is formed on the transfer material adsorbed on the transfer drum 15. The transfer material on which a desired toner image is formed is peeled off by the peeling electrode 19 and is conveyed to the fixing section to obtain the final fixed multicolor toner image. On the other hand, the transfer drum 15 removes the remaining charges from the electrode 20.
And used for the next process.

Next, the batch transfer method will be described with reference to FIG.

Since each part of the apparatus is the same as the example of FIG. Here, reference numeral 21 denotes a transport unit that transfers the toner image while transporting the transported transfer material. Photoconductor drum 1
Electric charges are uniformly formed on the surface 4 by a charging electrode, and then an electrostatic latent image is formed by a latent image forming means (means not shown).
This electrostatic latent image is developed by a developing device having a toner (for example, black toner) of one color of the developing unit 12, and a toner image of one color is formed on the photosensitive drum. In the illustrated example, this toner image is not transferred, and the charge electrode 11 uniformly forms an electric charge again on the photosensitive drum having the toner image as it is, and further an electrostatic latent image is formed. Then, it is developed by a developing device having a toner of a color different from the above, and a toner image of another color is formed by being superposed on the previous toner image. During this time, cleaning unit 1
3, the transfer electrode 18, and the transport unit 21 do not operate, and are retracted from the photoconductor drum 14 so as not to disturb the toner image on the photoconductor drum 14.

After the desired image formation is completed and the multicolor toner image is formed, the toner image on the photosensitive drum is transferred onto the transfer material carried by the carrying unit 16 while being carried by the carrying section 21. The toner image is transferred by the electrode 18. The transfer material carrying the transferred toner image is transported to a fixing unit, where it is fixed, and a final multicolor toner image is formed on the transfer material. After the toner image is transferred, the toner remains on the photosensitive drum 14, so that the cleaning unit 13 cleans the toner and the toner is used in the next process.

The toner image formed on the photoconductor by the various methods described above is transferred to a transfer material such as paper in a transfer process. The transfer method is not particularly limited, and various methods such as a so-called corona transfer method and a roller transfer method can be adopted.

Since the toner of the present invention has a high transfer efficiency and a small amount of toner remains on the photosensitive member, the pressing force of the blade to the photosensitive member can be reduced when used in, for example, a blade cleaning system. It also has an effect that it can contribute to a longer life.

After the toner image is transferred to the transfer material, the toner remaining on the photoconductor is removed by cleaning, and the photoconductor is repeatedly used in the next process.

In the present invention, the cleaning mechanism is not particularly limited, and any known cleaning mechanism such as a blade cleaning system, a magnetic brush cleaning system, a fur brush cleaning system or the like can be arbitrarily used. A preferable cleaning mechanism is a blade cleaning method using a so-called cleaning blade for the above-described reason.

[0103]

The present invention will be described in detail below with reference to examples, but the embodiments of the present invention are not limited thereto.

Example 1 Production Example 1 [ Preparation of Colorant Dispersion Liquid] As a colorant, 25.6 kg of carbon black (Regal R330, manufactured by Cabot) was added with 11.98 kg of sodium dodecyl sulfate and 265 l of ion-exchanged water. After mixing, a pressure-dispersion homogenizer (NPH-70) manufactured by Nippon Seiki Seisakusho Co., Ltd. was used to prepare a colorant dispersion liquid having a dispersed particle diameter of 10 times or less the primary particle diameter of carbon black. The dispersed particle diameter of the colorant was measured by using a laser diffraction particle size distribution analyzer SALD-1100 (manufactured by Shimadzu Corporation), and as a result, the number average particle diameter was 0.22 μm.

[Synthesis of Colored Polymer Particles] 500 l of G equipped with a stirrer, a temperature sensor, a cooling pipe, and a nitrogen introducing device
Into an L reactor, add 16 l of the above colorant dispersion to 250 l of degassed ion-exchange distilled water, and further add 27.86 k of styrene.
g, normal butyl acrylate 5.22 kg, methacrylic acid 1.74 kg, t-dodecyl mercaptan 0.3 k
g was added and the internal temperature was raised to 75 ° C. while stirring at a stirring speed of 500 rpm under a nitrogen stream. When the internal temperature reached 75 ° C., an aqueous polymerization initiator solution obtained by dissolving 0.82 kg of potassium persulfate in 60 l of degassed ion-exchange distilled water was added, and the mixture was polymerized for 7 hours and then cooled to room temperature. The generated particles were measured using an electrophoretic light scattering photometer ELS-800 (manufactured by Otsuka Electronics Co., Ltd.). By the above method, a colorant composite polymer particle dispersion liquid 1 having a number average particle diameter of 170 nm was obtained.

[Generation of Non-Spherical Particles] A cross-sectional view of a stainless reaction vessel 31 equipped with a 500 l thermometer 32 equipped with a stirring device, a temperature sensor, a cooling pipe, and a nitrogen introducing device, an anchor stirring blade 33, and a baffle 34 (FIG. Into 4), 150 l of the above colorant composite polymer particle dispersion liquid 1 was put and 100 rp at room temperature.
Stir at m. Here, 7.56 kg of potassium chloride is added.
An aqueous solution of potassium chloride dissolved in 0 l of distilled water was added,
Then 37 l of isopropanol were added. The liquid temperature at the end of the addition was 29.0 ° C. This mixture was heated to 85 ° C. The temperature rise of the association liquid measured at this time by the temperature monitor was 29 to 75 ° C. at an average heating rate of 1.5 ° C./min.
The average heating rate from 0 ° C to 85 ° C was 0.14 ° C / min.
(FIG. 5: Temperature rising profile) After that, association was performed at a liquid temperature of 85 ° C. (change was ± 3 ° C. or less) for 6 hours, and then cooled to room temperature (40 ° C. or less).

The particle size of this reaction solution was measured using a laser diffraction particle size distribution analyzer SALD-1100 (manufactured by Shimadzu Corporation), and as a result, associated non-spherical particles having a particle size of 5.42 μm were obtained. Further, the non-spherical particles are filtered, suspended and dispersed in distilled water, and a 1N sodium hydroxide aqueous solution is used to adjust pH = 1.
After adjusting to 3, the carboxylic acid was completely dissociated, washing was repeated to remove impurities such as an electrolyte, and filtration and drying were performed to obtain a polymerized toner 1 (lot 1).

Using the composite polymer particle dispersion liquid 1, the same operation as above was carried out twice to obtain a polymerized toner 1 (lot 2) and a polymerized toner 1 (lot 3).

Production Example 2 In Production Example 1, carbon black (Regal R33
0, manufactured by Cabot Corporation) instead of C.I. I. Pigmen
Polymerized toner 2 lots 1 to 3 were obtained in the same manner except that t Blue 15: 3 was used.

Production Example 3 In Production Example 1, carbon black (Regal R33
0, manufactured by Cabot Corporation) instead of C.I. I. Pigmen
Polymerized Toner 3 lots 1 to 3 were obtained in the same manner except that t Red122 was used.

Production Example 4 In Production Example 1, carbon black (Regal R33
0, manufactured by Cabot Corporation) instead of C.I. I. Pigmen
Polymerization Toner 4 lots 1 to 3 were obtained in the same manner except that t Yellow 17 was used.

Production Example 5 Polymerized toner 5 lots 1 to 3 were obtained in the same manner as in Production Example 1 except that an ultrasonic homogenizer (US-150T, manufactured by Nippon Seiki Seisakusho Co., Ltd.) was used in the preparation of the colorant dispersion. It was

Production Example 6 In Production Example 2, a liquid in which 11.86 kg of potassium chloride was dissolved in 80 l of distilled water was added at the time of formation of non-spherical particles, and then 35 l of isopropanol was added.
Liquid 30 prepared by dissolving 3.3 kg of polyoxyethylene (10) octyl phenyl ether (manufactured by Wako Pure Chemical Industries, Ltd.) in distilled water.
lot 1 of polymerized toner 6 was added in the same manner except that 1 was added.
~ 3.

Production Example 7 In the same manner as in Production Example 3, except that 11.86 kg of potassium chloride dissolved in 80 l of distilled water was added when non-spherical particles were produced, and then 30 l of isopropanol was added. 7 lots 1-3 were obtained.

Production Example 8 Polymerized toner 8 lots 1 to 3 were obtained in the same manner as in Production Example 3, except that an ultrasonic homogenizer (US-150T, manufactured by Nippon Seiki Seisakusho Co., Ltd.) was used together with the colorant dispersion. It was

Comparative Production Example 1 In Production Example 1, the average rate of temperature rise of the association liquid measured by the temperature monitor was 29 ° C. to 75 ° C. and the average rate of temperature rise was 1.5 ° C. /
Min. To 0.3 ° C./min, and Comparative Polymerization Toner 1 lots 1 to 3 were obtained in the same manner except that the average heating rate from 75 ° C. to 85 ° C. was changed to 0.74 ° C./min.

Comparative Production Example 2 In Production Example 2, the average rate of temperature rise of the association liquid measured by the temperature monitor was 29 to 75 ° C. and the average rate of temperature rise was 1.5 ° C. /
From the minutes, the average temperature rising rate of 20 to 73 ° C. was changed to 0.1 ° C./minute, and the average temperature rising rate of 75 to 85 ° C. was 0.74 ° C./minute.
Comparative Polymerized Toner 2 lots 1 to 3 were obtained in the same manner except that the average temperature rising temperature of 73 to 86 ° C. was changed to 1.55 ° C./min.

Comparative Production Example 3 In Production Example 1, the average rate of temperature rise of the association liquid measured by the temperature monitor was 29 to 75 ° C. and the average rate of temperature rise was 1.5 ° C. /
Min. To 1.4 ° C./min, and the average heating rate of 75 ° C. to 85 ° C. was changed from 0.74 ° C./min to 1.4 ° C./min. Got 3.

(BET Value) The BET value was measured by using a flow soap II2300 manufactured by Shimadzu Corporation through N ₂ gas by a one-point method.

[0120]

[Table 1]

(Volume Average Particle Size and Particle Size Distribution) The volume average particle size and particle size distribution are SALD1 manufactured by Shimadzu Corporation.
It was measured using 100.

CV is a value obtained by dividing the standard deviation of the volume average particle diameter by the volume average particle diameter.

[0123]

[Table 2]

[Evaluation] The toner of the present invention and the comparative toner were mixed at a toner concentration of 5% by weight with a carrier obtained by coating ferrite particles having a volume average particle diameter of 60 μm with a styrene / methyl methacrylate copolymer at 20 ° C. and 50% RH. And 30
The charge amount was measured under the environment of ℃ and 85% RH. Result is,
The results are shown in Table 3 below.

[0125]

[Table 3]

Probably because the toner of the present invention has a charge control group on the surface of the particles, it has excellent chargeability, there is little variation between lots, and there is little change even under high temperature and high humidity.
On the other hand, the comparative toner has a large variation between lots.

[Embodiment 2] An electrophotographic copying machine "Konica U-BIX3035" (Konica Corp.) using the above developer and equipped with a heat roller fixing device and a cleaning blade.
(Manufactured by Mfg. Co., Ltd.), an actual copying test for forming a copy image was performed, and the following items were evaluated after the initial and continuous 10,000 copies.

(1) Resolution A copy image of a thin line chart was formed and judged by the number of recognizable thin lines per 1 mm.

(2) Fogging Copy images are continuously formed in a normal temperature and normal humidity environment (temperature 20 ° C., relative humidity 50%), and the “Sakura densitometer PD
A-60 "(manufactured by Konica Corp.) was used to measure the reflection density of a white background portion to determine fogging.

[0130]

[Table 4]

The polymerized toners 1 to 8 in the invention show stable and excellent characteristics in both resolution and fog.
It can be seen that the comparative polymerized toners 1 to 3 have a problem in at least one of the properties.

[Embodiment 3] "Konica 9028"
(2 component non-contact development digital copying machine manufactured by Konica Corp.) was used, and polymerized toners 1, 2, 3 and 4 and comparative polymerized toners 1 and 2 were used, and the performance was examined with the following combinations. Ferrite particles having a volume average particle diameter of 45 μm were mixed with a carrier coated with a styrene / methyl methacrylate copolymer at a toner concentration of 10%. The resolution and fog were evaluated in the same manner as above, and the results are shown in Table 5 below. Lot No. 2 was used for each toner.

1) Polymerized toner 1, 2, 3, 4 2) The polymerized toner 1 is changed to the comparative polymerized toner 1 by the combination of 1) 3) The polymerized toner 2 is changed to the comparative polymerized toner 2 by the combination of 1).

[0134]

[Table 5]

Also in this example, it is understood that only the combination of 1) using the toner in the present invention has sufficient characteristics.

[0136]

According to the present invention, particles having a uniform particle size distribution and a uniform charge amount can be obtained with good reproducibility. This makes it possible to manufacture a toner having good resolution and less fog.

The toner of the present invention has excellent chargeability and environmental resistance and is stable. Further, it has a high resolution, a clear image with less fogging can be obtained, and it has excellent printing durability. Furthermore, there is little variation between lots during manufacturing.

[Brief description of drawings]

FIG. 1 is a schematic view showing an example of a non-contact developing system.

FIG. 2 is a schematic diagram showing an example of a sequential transfer system.

FIG. 3 is a schematic view showing an example of a batch transfer method.

FIG. 4 is a sectional view of a stainless steel reaction kettle.

FIG. 5 is a temperature rise profile diagram.

[Description of Reference Signs] 1 photoconductor 2 developer carrier 2A developing sleeve 2B magnet 3 two-component developer (containing toner of the present invention) 4 developer layer regulating member 5 developing area 6 developer layer 7 for forming an alternating electric field Power source 11 charging electrode 12 developing unit 13 cleaning unit 14 photoconductor drum 15 transfer drum 16 transport unit 17 adsorption electrode 18 transfer electrode 19 peeling electrode 20 removal electrode 21 transport section

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Mikio Kamiyama 1 Konica Stock Company, Sakura Town, Hino City, Tokyo (72) Inventor Chie Kikuchi 1 Konica Stock Company, Sakura City, Hino City, Tokyo In-house

Claims (8)

[Claims] 1. A method for producing polymer particles by associating a plurality of polymer particles, which are emulsified and dispersed in water,
At the time of the association, a step of adding an organic solvent that is infinitely soluble in water and does not dissolve the polymer fine particles, the association temperature is from room temperature to 1 to more than the boiling point of the mixed solvent of the organic solvent and water.
A method for producing polymer particles, comprising a step of rapidly raising the temperature to a temperature lower by 30 ° C., and then a step of raising the temperature to near the boiling point of the mixed solvent at a slower rate than the previous step. 2. The method according to claim 1, further comprising a step of washing, filtering and drying the polymer particles after the step of raising the temperature to near the boiling point of the mixed solvent at a slower rate than the previous step. Method for producing coalesced particles. 3. The method for producing polymer particles according to claim 1, wherein the polymer particles are toner for developing an electrostatic latent image. 4. An electrostatic latent image developing toner produced by the method for producing an electrostatic latent image developing toner according to claim 2. 5. The toner has a BET specific surface area of 5 to 10.
The toner for developing an electrostatic latent image according to claim 4, wherein the toner has an amount of 0 m ² / g. 6. An image forming method in which an electrostatic charge latent image formed on a photoconductor is visualized to form a toner image, wherein the electrostatic charge latent image developing toner according to claim 4 is used. Forming method. 7. An image forming method for transferring a toner image formed on a photoconductor to a transfer material, wherein the electrostatic latent image developing toner according to claim 4 is used. 8. An electrostatic latent image according to claim 4 or 5, wherein in the image forming method, the toner image formed on the photoconductor is transferred onto a transfer material, and then the residual toner on the photoconductor is cleaned and removed. An image forming method characterized by using a developing toner.