JP2003316064A - Toner for developing electrostatic charge image, its production method and image forming method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide toner for developing an electrostatic charge image using resin in which residual monomers are restrained to be few and whose molecular weight distribution is broad by finding out the excellent ratio relation of the chain transfer constant of a chain transfer agent in the case of using a plurality of chain transfer agents at the time of composing resin for toner in order to extend the non-offset area of the toner, and to provide the manufacture method of the toner and an image forming method. <P>SOLUTION: In polymerization method toner consisting of a colorant and resin constituted by polymerizing polymerized monomer incorporating the chain transfer agent in a water medium, two or more kinds of chain transfer agents are used and the ratio of the constant (TA) of the agent having the larger chain transfer constant to the constant (TB) of the agent having the smaller one has following relation: 2≤TA/TB≤500. TA means the chain transfer constant of the chain transfer agent A, and TB means the chain transfer constant of the chain transfer agent B. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrostatic charge image developing toner (sometimes referred to simply as toner) and a method for producing the same.
And an image forming method using the same.

[0002]

2. Description of the Related Art At present, in an image forming apparatus which is required to have high speed and high image quality, a dry type electrostatic charge image developing method using almost all powdered toner (electrophotographic method is used as a typical method). Sometimes called a method) is used.

Recently, the biggest improvement problem in the electrostatic image developing method is to further improve the image quality, and therefore, a toner having a small particle size and a uniform particle distribution has been used. It is difficult to produce a toner having a small particle diameter and a uniform particle distribution by a pulverization method which is a widely used toner manufacturing method, and a so-called polymerization method toner is used.

However, the polymerization toner can relatively easily obtain a toner having a small particle size and a uniform particle distribution.
The degree of polymerization (molecular weight) of the resin tends to be uniform, and the problem in that case is the problem of toner offset during contact heat fixing.

In order to develop a toner that is firmly fixed and does not cause an offset even if the fixing temperature of the image forming apparatus varies to some extent, it is essential to expand the non-offset area of the toner. For that purpose, the toner resin is preferably designed to have a broad molecular weight distribution.

[0006]

The main substance for controlling the molecular weight of the toner resin is a chain transfer agent. However, one type tends to have a single molecular weight distribution and is not suitable for the chain transfer constant. In the case of no molecular weight design, the residual monomer also increases. Further, even if there are two or more kinds, those having a similar chain transfer constant have a single distribution, and those having a chain transfer constant that is too far apart increase the residual monomer.

An object of the present invention is to find a good ratio relationship of the chain transfer constants of the chain transfer agents when a plurality of chain transfer agents are used in the synthesis of the resin for toner in order to expand the non-offset area of the toner. It is in. Another object of the present invention is to provide a toner for developing an electrostatic image using a resin having a small residual monomer content and a broad molecular weight distribution, a method for producing the same, and an image forming method.

[0008]

Means for Solving the Problems As a result of intensive studies, the present inventors have found that the object of the present invention can be achieved by adopting any one of the following constitutions.

[1] In a toner for developing an electrostatic charge image, which comprises a resin obtained by polymerizing a polymerizable monomer (monomer) containing a chain transfer agent in an aqueous medium and a colorant, the chain transfer agent is 2 A toner for developing an electrostatic charge image, characterized in that the ratio of the constant (TA) having a larger chain transfer constant and the constant (TB) having a smaller chain transfer constant has the following relationship.

2 ≦ TA / TB ≦ 500 TA: chain transfer constant of chain transfer agent A TB: chain transfer constant of chain transfer agent B [2] [1] characterized in that the residual monomer amount is 200 ppm or less. The toner for developing an electrostatic image as described above.

[3] The toner for developing an electrostatic image according to [1], wherein the ratio of the amount of the chain transfer agent A to the amount of the chain transfer agent B used is 1: 9 to 9: 1.

[4] In the method for producing the toner for developing an electrostatic image according to any one of [1] to [3], a polymerizable monomer is polymerized in an aqueous medium to prepare resin fine particles. Then, a method for producing a toner for developing an electrostatic charge image is characterized in that the toner particles are obtained by mixing with colorant particles and salting out, aggregating, and fusing.

[5] A step of forming an electrostatic charge image on an electrostatic charge image carrier, a step of developing the electrostatic charge image with a developer containing a toner for developing an electrostatic charge image to form a toner image, and a toner image An electrostatic charge image developing method according to any one of [1] to [3], which is used as an electrostatic charge image developing toner in an image forming method including a step of transferring onto a transfer body and a step of contact heating and fixing after transfer. An image forming method using a toner for use.

As described above, the chain transfer constant ratio of the chain transfer agent used in the present invention is 2 or more and 500 or less, more preferably 50 or more and 200 or less. When the chain transfer constant ratios are less than 2 and the chain transfer constants are close to each other, the molecular weight distribution becomes too simple. on the other hand,
If the chain transfer constant ratio is far from 500, the residual monomer will increase.

Further, the amount ratio (mol ratio) of the chain transfer agents used in combination is preferably in the range of 1: 9 to 9: 1. In this range, the effect of changing the chain transfer constant is sufficiently exhibited. It However, the more preferable range is 3: 7 to 7: 3. Further, the total amount of the chain transfer agent used is preferably 0.1 to 3.0 mol% of the polymerizable monomer.

The definition of the chain transfer constant is as follows.

[0017]

[Equation 1]

The chain transfer constant in the present invention is a chain transfer constant when the polymerizable monomer is styrene (60 ° C.).

In practice, as the chain transfer constant, a literature value (for example, "POLYMER HANDBOOK") or a value provided by the manufacturer who sells the chain transfer agent can be used.

However, if there is no literature value, it can be calculated by experiment. As a method, the concentration of the chain transfer agent including 0 point is 4 points or more, and AIBN (azobisisobutyronitrile) is used as an initiator in the presence of each concentration of the chain transfer agent, and the bulk of styrene is added at 60 ° C. Polymerize.

The amount of decrease in the chain transfer agent at this time is determined by using a capillary column: HR-1, the monomer conversion rate and the molecular weight of the polymer are determined by GPC, and the chain transfer constant is calculated.

Further, the residual monomer can be measured by a head space type gas chromatograph using a detection method used in a normal gas chromatograph such as an internal standard method. This method encloses the toner in an open / close container, heats it at the time of heat fixing of a copying machine, etc., and quickly injects the gas in the container into the gas chromatograph when the container is filled with volatile components and volatilizes. In addition to measuring the component amounts, the headspace method of the present invention uses M
S (mass spectrometry) is also performed.

In the headspace method of the present invention, it is possible to observe all peaks of volatile components by gas chromatography, and to quantify the residual components by using an analytical method utilizing electromagnetic interaction. It can be achieved with a high degree of accuracy.

The measuring method according to this method will be described below. <Headspace gas chromatograph measurement method> 1. Sample Collection 0.8 g sample is collected in a 20 ml headspace vial. The sample amount is weighed up to 0.01 g (necessary to calculate the area per unit mass). Seal the vial with a septum using a dedicated crimper.

2. Heating of sample The sample is put in a thermostat bath at 130 ° C in an upright state and heated for 30 minutes.

3. Silicone oil SE-3 so that the set mass ratio of gas chromatographic separation conditions is 15%
A carrier coated with 0 in a column having an inner diameter of 3 mm and a length of 3 m is used as a separation column. The separation column is attached to a gas chromatograph, and He is used as a carrier to flow at 50 ml / min. The temperature of the separation column is 40
C., and the temperature is raised to 260.degree. C. at 15.degree. After reaching 260 ° C, hold for 5 minutes.

4. Introducing the sample The vial bottle is taken out of the thermostat, 1 ml of the gas generated from the sample is immediately collected with a gas tight syringe, and this is injected into the separation column.

5. A calibration curve is prepared in advance using xylene as an internal reference substance, and the concentration of each component is determined.

6. Equipment (1) Headspace condition Headspace device HP7694 “Head manufactured by Hewlett-Packard Company
Space sampler "Temperature condition Transfer line: 200 ° C Loop temperature: 200 ° C Sample amount: 0.8 g / 20 ml vial (2) GC / MS condition GC Hewlett Packard HP5890 MS Hewlett Packard HP5971 column: HP-624 30 m x 0 0.25 mm oven temperature: 40 ° C (3 min) -15 ° C / min-
260 ° C. Measurement mode: SIM Here, the range of the residual monomer amount is preferably 200 ppm or less, and more preferably 0.1 to 100 ppm.

[0030]

BEST MODE FOR CARRYING OUT THE INVENTION The toner according to the present invention, the manufacturing method thereof, the image forming method, and other matters relating to the present invention will be further described.

[Toner Manufacturing Method] The toner manufacturing method is not particularly limited, and any known so-called polymerization method can be used.

However, preferably, the toner of the present invention is a suspension polymerization method or an emulsion polymerization method, and in particular, a polymerizable monomer is polymerized in a liquid (in an aqueous medium) to which an emulsion is added to form resin fine particles. It is preferable that the resin particles are prepared and then added with an aggregating agent such as an organic solvent or a salt to aggregate and fuse the resin particles.

(Suspension Polymerization Method) Various constituent materials such as a coloring agent and, if necessary, a release agent, and a polymerization initiator are added to the polymerizable monomer, and a homogenizer, a sand mill, a sand grinder and an ultrasonic wave are used. Various constituent materials are dissolved or dispersed in the polymerizable monomer using a disperser or the like.

The polymerizable monomer in which the various constituent materials are dissolved or dispersed is formed into an oil droplet having a desired size as a toner by using a homomixer or a homogenizer in an aqueous medium containing a dispersion stabilizer. Disperse. The "aqueous medium" in the present invention means that at least 50
It indicates that the content is at least mass%.

After that, the reaction mixture is transferred to a reactor having a stirring mechanism and heated to advance the polymerization reaction. After completion of the reaction, the dispersion stabilizer is removed, filtered, washed, and dried to prepare the toner of the present invention.

(Emulsion Polymerization Method) As a method for producing the toner of the present invention, resin fine particles prepared by emulsion polymerization are used.
A method of preparing by salting out, aggregating, and fusing in an aqueous medium is particularly preferable. This method is not particularly limited, but for example, the methods described in JP-A-5-265252, JP-A-6-329947, and JP-A-9-15904 can be mentioned.

That is, resin particles and dispersed particles of a constituent material such as a colorant, or a method of salting out, aggregating and fusing a plurality of fine particles composed of a resin and a colorant in advance, especially in water. After dispersing using an emulsifier, at the same time salting out by adding a coagulant having a critical coagulation concentration or higher, gradually forming a fused particle by heat fusion above the glass transition temperature of the formed polymer itself. When the particle size is grown and the target particle size is reached, a large amount of water is added to stop the particle size growth, and the particle surface is smoothed while heating and stirring to control the shape, The toner of the present invention can be formed by heating and drying as it is in a fluid state. Here, a solvent such as alcohol, which is infinitely soluble in water, may be added together with the coagulant.

(Specific Manufacturing Method) Next, a specific manufacturing example by the polymerization method will be described. Actually, the step of polymerizing the polymerizable monomer may be divided into multiple steps instead of one step.

Composite Resin Particles Obtained by Multi-Stage Polymerization Method An example in which the release agent is contained in the region other than the outermost layer of the composite resin particles is shown.

The toner manufacturing process mainly includes the following steps. 1: Area where the release agent is other than the outermost layer (central part or middle layer)
Multi-stage polymerization step (I) for obtaining composite resin particles contained in: 2: salting out / fusion step (II) 3 for salting out / fusing composite resin particles and colorant particles to obtain colored particles : Filtering / washing step of filtering the colored particles from a dispersion of the colored particles to remove a surfactant and the like from the colored particles 4: Drying step 5 of drying the washed colored particles: Dryed colored particles To a toner by adding an external additive to the toner.

Hereinafter, each step will be described in detail. Multistage Polymerization Step (I) The multistage polymerization step (I) is a step of producing composite resin particles by a multistage polymerization method in which a coating layer made of a polymer of a monomer is formed on the surface of the resin particles.

In the present invention, it is preferable to employ a multi-step polymerization method of three or more steps from the viewpoint of stability of production and crushing strength of the obtained toner.

The two-step polymerization method and the three-step polymerization method, which are typical examples of the multi-step polymerization method, will be described below.

<Two-step polymerization method> The two-step polymerization method is composed of a central portion (nucleus) formed of a high molecular weight resin containing a release agent and an outer layer (shell) formed of a low molecular weight resin. Is a method for producing composite resin particles.

This method will be described in detail. First, a releasing agent is dissolved in a monomer K to prepare a monomer solution, and the monomer solution is added to an aqueous medium (for example, an aqueous surfactant solution). After the oil droplets are dispersed in the system, the system is polymerized (first stage polymerization).
By doing so, a dispersion liquid of high molecular weight resin particles containing a release agent is prepared.

Then, a polymerization initiator and a monomer K for obtaining a low molecular weight resin are added to the dispersion liquid of the resin particles,
Polymerization of monomer K in the presence of resin particles (second stage polymerization)
Is a method of forming a coating layer made of a low molecular weight resin (polymer of monomer K) on the surface of the resin particles.

<Three-step polymerization method> The three-step polymerization method comprises a central portion (nucleus) formed of a high molecular weight resin, an intermediate layer containing a release agent, and an outer layer (shell) formed of a low molecular weight resin. It is a method for producing composite resin particles.

To explain this method in detail, first, a dispersion of resin particles obtained by a polymerization treatment (first-stage polymerization) according to a conventional method is added to an aqueous medium (for example, an aqueous solution of a surfactant). In addition to the addition, a monomer solution obtained by dissolving the release agent in the monomer M is dispersed in the aqueous medium as an oil droplet, and then the system is subjected to a polymerization treatment (second-stage polymerization).
On the surface of the resin particles (core particles), a coating layer (intermediate layer) made of a resin (polymer of the monomer M) containing a release agent is formed to form composite resin particles (high molecular weight resin-intermediate molecular weight resin). )
A dispersion liquid is prepared.

Next, a polymerization initiator and a monomer K for obtaining a low molecular weight resin are added to the obtained dispersion liquid of the composite resin particles, and the monomer K is polymerized in the presence of the composite resin particles. By performing (third stage polymerization), a coating layer made of a low molecular weight resin (polymer of monomer K) is formed on the surface of the composite resin particles. In the above method, by incorporating the second stage polymerization, the release agent can be finely and uniformly dispersed, which is preferable.

The aqueous medium referred to in the present invention is, for example, water 50.
A medium consisting of -100% by mass and a water-soluble organic solvent 0-50% by mass. Examples of the water-soluble organic solvent include methanol, ethanol, isopropanol, butanol, acetone, methyl ethyl ketone, tetrahydrofuran, and the like, and alcohol-based organic solvents that do not dissolve the obtained resin are preferable.

Further, according to the method of forming oil droplets mechanically (miniemulsion method), unlike the usual emulsion polymerization method, the release agent dissolved in the oil phase is not released and is formed. A sufficient amount of release agent can be introduced into the resin particles or coating layer to be used.

Here, the disperser for dispersing the oil droplets by mechanical energy is not particularly limited, and for example, a stirrer "CLEARMIX" (M -Technique Co., Ltd.), ultrasonic disperser, mechanical homogenizer,
Menton Gorin, a pressure type homogenizer, etc. can be mentioned. Further, as the dispersed particle size, 10 to
1000 nm, preferably 50-1000 nm,
More preferably, it is 30 to 300 nm.

As another polymerization method for forming resin particles or a coating layer containing a release agent, an emulsion polymerization method,
Known methods such as a suspension polymerization method and a seed polymerization method can also be adopted. In addition, these polymerization methods include resin particles (core particles) or a coating layer that form composite resin particles,
It can also be employed to obtain a release agent-free product.

The particle size of the composite resin particles obtained in this polymerization step (I) is determined by the electrophoresis light scattering photometer "ELS-80".
0 "(manufactured by Otsuka Electronics Co., Ltd.) is preferably in the range of 10 to 1000 nm as the weight average particle diameter.

Further, the glass transition temperature (T
g) is preferably in the range of 48 to 74 ° C, more preferably 52 to 64 ° C.

The softening point of the composite resin particles is 95-14.
It is preferably in the range of 0 ° C. Salting-out / fusion step (II) In this salting-out / fusion step (II), the composite resin particles obtained in the above-mentioned polymerization step (I) and the colorant particles are salted out / fused (with salting out). This is a process of obtaining amorphous (non-spherical) toner particles by simultaneously causing fusion and fusion.

The term "salting out / fusion" used in the present invention means that salting out (aggregation of particles) and fusion (disappearance of the interface between particles) occur simultaneously, or salting out and fusion occur simultaneously. Refers to an act. In order to perform salting out and fusion at the same time, particles (composite resin particles, colorant particles) are formed under the temperature condition of the glass transition temperature (Tg) of the resin constituting the composite resin particles or higher.
Need to be aggregated.

In this salting-out / fusion step (II), internal additive particles (fine particles having a number average primary particle diameter of about 10 to 1000 nm) such as a charge control agent are salted out together with the composite resin particles and the colorant particles. / May be fused. Further, the colorant particles may be surface-modified, and as the surface-modifying agent,
Conventionally known ones can be used.

The colorant particles are subjected to salting-out / fusion treatment in a state of being dispersed in an aqueous medium. The aqueous medium in which the colorant particles are dispersed is preferably an aqueous solution in which the surfactant is dissolved at a concentration equal to or higher than the critical micelle concentration (CMC).

The disperser used for the dispersion treatment of the colorant particles is not particularly limited, but preferably a stirring device "CLEARMIX (CLEAR) equipped with a rotor rotating at high speed.
MIX) "(manufactured by M-Technique Co., Ltd.), ultrasonic disperser,
Examples thereof include a pressure homogenizer such as a mechanical homogenizer, Manton-Gaulin, a pressure homogenizer, and a medium type homogenizer such as a Getzman mill and a diamond fine mill.

In order to salt out / fuse the composite resin particles and the colorant particles, the salting agent (aggregating agent) having a critical coagulation concentration or more is added to the dispersion liquid in which the composite resin particles and the colorant particles are dispersed. ) Is added and the dispersion is heated to the glass transition temperature (Tg) or higher of the composite resin particles.

A suitable temperature range for salting out / fusing is (Tg + 10 ° C.) to (Tg + 50 ° C.),
Particularly preferably, it is (Tg + 15 ° C.) to (Tg + 40 ° C.). In addition, an organic solvent infinitely soluble in water may be added in order to effectively carry out the fusion.

Filtration / Washing Step In this filtration / washing step, a filtering treatment for filtering the toner particles from the dispersion system of the toner particles obtained in the above step, and the filtered toner particles (cake-like aggregates) ) Is subjected to a cleaning treatment for removing deposits such as surfactants and salting-out agents.

Here, the filtration method is not particularly limited, such as a centrifugal separation method, a vacuum filtration method using a Nutsche or the like, or a filtration method using a filter press or the like.

Drying Step This step is a step of drying the washed toner particles.

Examples of the dryer used in this step include a spray dryer, a vacuum freeze dryer, a vacuum dryer, a stationary shelf dryer, a mobile shelf dryer, a fluidized bed dryer, and a rotary dryer. It is preferable to use a dryer or a stirring dryer.

The water content of the dried toner particles is preferably 5% by mass or less, more preferably 2% by mass or less.

The dried toner particles are
When the aggregates are aggregated by the weak attraction between particles, the aggregates may be crushed. Here, as the disintegration processing device,
A mechanical crushing device such as a jet mill, a Henschel mixer, a coffee mill or a food processor can be used.

The toner of the present invention forms the composite resin particles in the absence of the colorant as described above, and the dispersion liquid of the colorant particles is added to the dispersion liquid of the composite resin particles to obtain the composite resin particles and the colorant. It is preferably prepared by salting out / fusing with particles. Thus, by carrying out the preparation of the composite resin particles in a system in which no colorant is present, the polymerization reaction for obtaining the composite resin particles is not hindered.

Further, as a result of the polymerization reaction being surely carried out to obtain the composite resin particles, no monomer or oligomer remains in the obtained toner particles, and the image forming method using the toner can be used. No offensive odor is generated in the heat fixing step.

Next, each constituent factor used in the toner manufacturing process will be described in detail. [Polymerizable Monomer] As the polymerizable monomer (sometimes simply referred to as a monomer) for producing the binder resin used in the present invention, a hydrophobic monomer is used as an essential constituent component, and necessary. A crosslinkable monomer is used according to the above. Further, as described below, it is desirable to contain at least one kind of monomer having an acidic polar group or monomer having a basic polar group.

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

Specifically, a monovinyl aromatic monomer,
(Meth) acrylic acid ester-based monomer, vinyl ester-based monomer, vinyl ether-based monomer, monoolefin-based monomer, diolefin-based monomer, halogenated olefin-based monomer, etc. may be used. it can.

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- Examples thereof include styrene-based monomers such as octylstyrene, pn-nonylstyrene, pn-decylstyrene, pn-dodecylstyrene, 2,4-dimethylstyrene, and 3,4-dichlorostyrene, and derivatives thereof. .

As the acrylic monomer, acrylic acid,
Methacrylic acid, 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, γ-aminoacrylate propyl, stearyl methacrylate, methacrylic Examples thereof include dimethylaminoethyl acid salt and diethylaminoethyl methacrylate.

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-based 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) Crosslinkable Monomer A crosslinkable monomer may be added to improve the properties of the resin particles. Examples of the crosslinkable monomer include those having two or more unsaturated bonds such as divinylbenzene, divinylnaphthalene, divinyl ether, diethylene glycol methacrylate, ethylene glycol dimethacrylate, polyethylene glycol dimethacrylate and diallyl phthalate.

(3) Monomer having acidic polar group As the monomer having an acidic polar group, (a) an α, β-ethylenically unsaturated compound having a carboxyl group (—COOH) and (b) sulfone An α, β-ethylenically unsaturated compound having a group (—SO ₃ H) can be mentioned.

Α, β- having a carboxyl group (a)
Examples of ethylenically unsaturated compounds include acrylic acid, methacrylic acid, fumaric acid, maleic acid, itaconic acid,
Examples thereof include cinnamic acid, maleic acid monobutyl ester, maleic acid monooctyl ester, and metal salts thereof such as Na and Zn.

Examples of the α, β-ethylenically unsaturated compound having a sulfone group (b) include sulfonated styrene,
Examples thereof include Na salts thereof, allylsulfosuccinic acid, octyl allylsulfosuccinate, and Na salts thereof.

(4) Monomer having a basic polar group The monomer having a basic polar group includes (i) an amine group or a quaternary ammonium group having 1 to 1 carbon atoms.
2, preferably 2 to 8, particularly preferably 2 (meth) acrylic acid ester of an aliphatic alcohol, (ii) (meth)
Acrylic amide or optionally 1 to 18 carbon atoms on N
(Meth) acrylic acid amide mono- or di-substituted with an alkyl group of, (iii) a vinyl compound substituted with a heterocyclic group having N as a ring member, and (iv) N, N-diallyl-alkylamine or a compound thereof. A quaternary ammonium salt can be illustrated. Among them, (meth) of aliphatic alcohol having an amine group or a quaternary ammonium group of (i)
Acrylic acid esters are preferred as the monomer having a basic polar group.

Examples of the (meth) acrylic acid ester of an aliphatic alcohol having an amine group or a quaternary ammonium group (i) include dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, diethylaminoethyl acrylate, diethylaminoethyl methacrylate, and Quaternary ammonium salt of 4 compounds, 3-dimethylaminophenyl acrylate, 2-hydroxy-
3-methacryloxypropyl trimethyl ammonium salt etc. can be mentioned.

The (meth) acrylic acid amide of (ii) or the (meth) acrylic acid amide optionally substituted with mono- or dialkyl on N includes acrylamide, N-butyl acrylamide, N, N-dibutyl acrylamide, piperidyl acrylamide, Methacrylamide, N-butylmethacrylamide, N, N-dimethylacrylamide,
N-octadecyl acrylamide etc. can be mentioned.

Examples of the vinyl compound (iii) substituted with a heterocyclic group having N as a ring member include vinyl pyridine and
Examples thereof include vinylpyrrolidone, vinyl-N-methylpyridinium chloride and vinyl-N-ethylpyridinium chloride.

Examples of the N, N-diallyl-alkylamine of (iv) include N, N-diallylmethylammonium chloride and N, N-diallylethylammonium chloride.

[Polymerization Initiator] The radical polymerization initiator used in the present invention can be appropriately used if it is water-soluble. For example, persulfates (eg, potassium persulfate, ammonium persulfate, etc.), azo compounds (eg, 4,4 ′)
-Azobis-4-cyanovaleric acid and its salts, 2,2'-azobis (2-amidinopropane) salt, etc.), peroxide compounds and the like. Furthermore, the above radical polymerization initiator can be used as a redox initiator in combination with a reducing agent, if necessary. The use of a redox type initiator is preferable because the polymerization activity can be increased, the polymerization temperature can be lowered, and the polymerization time can be further shortened.

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 to 90 ° C. is used. However, it is also possible to carry out the polymerization at room temperature or at a temperature slightly higher than that by using a combination of a polymerization initiator which starts at room temperature, for example, a hydrogen peroxide-reducing agent (ascorbic acid etc.).

[Chain Transfer Agent] In the present invention, a plurality of chain transfer agents having different chain transfer constants within the above ranges are used for the purpose of adjusting the molecular weight.

The chain transfer agent is not particularly limited, but for example, a compound having a mercapto group such as octyl mercaptan, dodecyl mercaptan, tert-dodecyl mercaptan is used. In particular, the compound having a mercapto group suppresses the odor during heat fixing,
A toner having a sharp molecular weight distribution can be obtained, and the storability,
It is preferably used because of its excellent fixing strength and anti-offset property, and preferred examples thereof include ethyl thioglycolate, propyl thioglycolate, propyl thioglycolate, butyl thioglycolate, t-butyl thioglycolate, and thioglycolic acid. 2-ethylhexyl, octyl thioglycolate, decyl thioglycolate, dodecyl thioglycolate, compounds having a mercapto group of ethylene glycol, compounds having a mercapto group of neopentyl glycol, compounds having a mercapto group of pentaerythritol You can

[Surfactant] It is preferable to use a surfactant to disperse oil droplets in an aqueous medium in order to carry out the miniemulsion polymerization using the above-mentioned polymerizable monomer. The surfactant that can be used in this case is not particularly limited, but the following ionic surfactants can be mentioned as examples of suitable compounds.

Examples of the ionic surfactant include sulfonates (sodium dodecylbenzene sulfonate,
Aryl alkyl polyether sodium sulfonate,
3,3-disulfone diphenylurea-4,4-diazo-
Sodium bis-amino-8-naphthol-6-sulfonate, ortho-carboxybenzene-azo-dimethylaniline, 2,2,5,5-tetramethyl-triphenylmethane-4,4-diazo-bis-β-naphthol -6-
Sodium sulfonate, etc.), sulfate ester salts (sodium dodecyl sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate, etc.),
Examples thereof include fatty acid salts (sodium oleate, sodium laurate, sodium caprate, sodium caprylate, sodium caproate, potassium stearate, calcium oleate, etc.).

Further, nonionic surfactants can also be used. Specifically, for example, polyethylene oxide, polypropylene oxide, a combination of polypropylene oxide and polyethylene oxide, ester of polyethylene glycol and higher fatty acid, alkylphenol polyethylene oxide, ester of higher fatty acid and polyethylene glycol, ester of higher fatty acid and polypropylene oxide, Examples thereof include sorbitan ester.

In the present invention, these surfactants are mainly used as an emulsifier during emulsion polymerization, but may be used for other steps or for other purposes.

[Molecular Weight Distribution of Resin Particles and Toner] The toner of the present invention has a peak or shoulder of 100,000 to 1.0.
It is preferably present at 0,000, and 1,000 to 50,000, with 100 or more peaks or shoulders.
000 to 1,000,000, 25,000 to 150,
It is even more preferred that it is present at 000 and 1,000 to 50,000.

The molecular weight of the resin particles is 100,000 to
A resin containing at least both a high molecular weight component having a peak or shoulder in the region of 1,000,000 and a low molecular weight component having a peak or shoulder in the region of 1,000 to less than 50,000 is preferable. More preferably, it is preferable to use an intermediate molecular weight resin having a peak or a shoulder at the peak molecular weight of 15,000 to 100,000.

The method for measuring the molecular weight of toner or resin is as follows:
Measurement by GPC (gel permeation chromatography) using THF (tetrahydrofuran) as a solvent is good. That is, 1.0 ml of THF is added to 0.5 to 5 mg of the measurement sample, more specifically 1 mg, and stirred at room temperature using a magnetic stirrer or the like to sufficiently dissolve the sample. Then, pore size 0.45-0.50
After processing with a μm membrane filter, it is injected into GPC. The measurement conditions of GPC are as follows: stabilize the column at 40 ° C., flow THF at a flow rate of 1.0 ml per minute, and
About 100 μl of a sample having a concentration of g / ml is injected and measured. The column is preferably used in combination with a commercially available polystyrene gel column. For example, Shodex GPC KF-801, 802, 8 manufactured by Showa Denko KK
03, 804, 805, 806, 807 combinations, Tosoh TSKgel G1000H, G2000H,
G3000H, G4000H, G5000H, G600
0H, G7000H, TSKguard column
And the like. A refractive index detector (IR detector) or a UV detector may be used as the detector. In measuring the molecular weight of a sample, the molecular weight distribution of the sample is calculated using a calibration curve prepared using monodisperse polystyrene standard particles. About 10 points may be used as polystyrene for preparing the calibration curve.

[Aggregating Agent] The aggregating agent used in the present invention is
Those selected from among the metal salts are preferred.

The metal salt may be a monovalent metal salt such as an alkali metal salt such as sodium, potassium or lithium, a divalent metal salt such as an alkaline earth metal salt such as calcium or magnesium, or a divalent metal such as manganese or copper. Valuable metal salt, iron,
Examples thereof include trivalent metal salts such as aluminum, polyaluminum hydroxide, polyaluminum chloride and the like.

Specific examples of these metal salts are shown below.
Specific examples of metal salts of monovalent metals include sodium chloride,
Examples of potassium chloride, lithium chloride, and metal salts of divalent metals include calcium chloride, zinc chloride, copper sulfate, magnesium sulfate, and manganese sulfate. Examples of the trivalent metal salt include aluminum chloride and iron chloride. These are appropriately selected according to the purpose. Generally, the divalent metal salt has a smaller critical aggregation concentration (coagulation value or coagulation point) than the monovalent metal salt, and the trivalent metal salt has a smaller critical aggregation concentration.

The critical aggregation concentration referred to in the present invention is an index relating to the stability of the dispersion in the aqueous dispersion, and indicates the concentration at the point where aggregation occurs when a flocculant is added. This critical coagulation concentration greatly changes depending on the latex itself and the dispersant. For example, Seizo Okamura et al., Polymer Chemistry 17,601
(1960) and the like, and the value can be known by following these descriptions. Also, as another method,
It is also possible to add a desired salt to the target particle dispersion liquid while changing the concentration, measure the ζ potential of the dispersion liquid, and set the salt concentration at the point where the ζ potential starts to change to the critical aggregation concentration.

In the present invention, the polymer fine particle dispersion is treated with a metal salt so as to have a concentration higher than the critical aggregation concentration. At this time, of course, directly add the metal salt,
Whether to add as an aqueous solution is arbitrarily selected according to the purpose. When it is added as an aqueous solution, the added metal salt needs to have a critical coagulation concentration of the polymer particles or more with respect to the volume of the polymer particle dispersion and the total volume of the metal salt aqueous solution.

The concentration of the metal salt as the aggregating agent in the present invention may be the critical coagulation concentration or more, but is preferably 1.2 times or more, more preferably 1.5 times or more the critical coagulation concentration.

[Colorant] Examples of the colorant (colorant particles to be salted out / fused with the composite resin particles) constituting the toner of the present invention include various inorganic pigments, organic pigments and dyes. You can As the inorganic pigment, conventionally known ones 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 2 to 20% by mass, preferably 3 to 15% by mass, based on the polymer.

When used as a magnetic toner, the above magnetite can be added. In this case, from the viewpoint of imparting a predetermined magnetic characteristic, 20 to 6 is contained in the toner.
It is preferable to add 0% by mass.

Known organic pigments and dyes can be used. Specific organic pigments and dyes are exemplified below.

As the pigment for magenta or red,
For example, C.I. 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. Pigment Red 15, C.I. I. Pigment Red 16, C.I. 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. I. Pigment Red 144, C.I. I.
Pigment Red 149, C.I. I. Pigment Red 1
66, C.I. I. Pigment Red 177, C.I. I. Pigment Red 178, C.I. I. Pigment Red 222
Etc.

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. 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 9
4, C.I. I. Pigment Yellow 138, C.I. I. Pigment Yellow 180, C.I. I. Pigment Yellow 1
85, C.I. I. Pigment Yellow 155, C.I. I. Pigment Yellow 156 and the like.

As the pigment for green or cyan,
For example, C.I. I. Pigment Blue 15, C.I. I. Pigment Blue 15: 2, C.I. I. Pigment Blue 1
5: 3, C.I. I. Pigment Blue 16, C.I. I. Pigment Blue 60, C.I. I. Pigment Green 7 and the like.

Examples of dyes include C.I. I. Solvent Red 1, 49, 52, 58, 63,
111, 122, C.I. I. Solvent yellow 1
9, the same 44, the same 77, the same 79, the same 81, the same 82, the same 9
3, ibid 98, ibid 103, ibid 104, ibid 112, ibid 16
2, C.I. I. Solvent Blue 25, 36, 60,
No. 70, No. 93, No. 95 and the like can be used, and a mixture thereof can also be used.

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

The colorant (colorant particles) constituting the toner of the present invention may be surface-modified. As the surface modifier, conventionally known ones 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 and vinyltrisilane. Chlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane,
γ-ureidopropyltriethoxysilane and the like can be mentioned. As the titanium coupling agent, for example, TTS, 9S, 38S, 41B, 46B, 55, 138, which is commercially available under the trade name "Planeact" manufactured by Ajinomoto Co., Inc.
Commercial products A-1, B- manufactured by Nippon Soda Co., Ltd. such as S, 238S.
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 can be mentioned. As the aluminum coupling agent, for example,
Examples include "Planeact AL-M" manufactured by Ajinomoto Co., Inc.

The amount of these surface modifiers added is preferably 0.01 to 20% by mass, more preferably 0.1 to 5% by mass, based on the colorant.

Examples of the method for modifying the surface of the colorant particles include a method in which a surface modifier is added to a dispersion liquid of the colorant particles and the system is heated to react.

The surface-modified colorant particles are collected by filtration, washed with the same solvent and filtered, and then dried.

[Release Agent] The toner used in the present invention is
It is preferable that the toner is obtained by fusing resin particles containing a release agent in an aqueous medium. Thus, by salting out / fusing the resin particles in which the release agent is included in the resin particles with the colorant particles in the aqueous medium, a toner in which the release agent is finely dispersed can be obtained.

In the toner of the present invention, a low molecular weight polypropylene (number average molecular weight of 1500 to 900) is used as a release agent.
0) and low molecular weight polyethylene and the like are preferable, and ester compounds represented by the following formulas are particularly preferable.

In the formula R ^1- (OCO-R ² ) _n , n is an integer of 1 to 4, preferably 2 to 4, more preferably 3 to 4, and particularly preferably 4. R ¹ , R
² represents a hydrocarbon group which may have a substituent. R ¹
Has 1 to 40 carbon atoms, preferably 1 to 20 carbon atoms, and more preferably 2 to 5 carbon atoms. R ² has 1 to 40 carbon atoms, preferably 16 to 30 carbon atoms, and more preferably 18 to 26 carbon atoms.

Next, examples of typical compounds are shown below.

[0124]

[Chemical 1]

[0125]

[Chemical 2]

The amount of the above compound added is 1 to 30% by mass, preferably 2 to 20% by mass, and more preferably 3 to 15% by mass, based on the whole toner.

The toner of the present invention is preferably prepared by encapsulating the above-mentioned releasing agent in resin particles by a mini-emulsion method and salting out and fusing with the colored particles.

[Step of Adding External Additive] This step is a step of adding the external additive to the dried toner particles.

The external additive particles are, in terms of composition, metal oxides such as silica, alumina and titanium oxide, or fine particles of methylmethacrylate, etc., and when mixed with colored particles which are the toner base, they have a fluidizing effect. I have what I have.

The equipment used for adding the external additive includes a Turbuler mixer, a Henschel mixer,
Various known mixing devices such as a Nauta mixer and a V-type mixer can be mentioned.

The addition amount of the external additive is preferably about 0.1 to 5 mass% with respect to the toner.

In the present invention, the surface of the treatment layer treated with the silane coupling agent may be further coated with the coupling agent and / or silicone oil.

That is, after the silane coupling agent is treated in an aqueous medium, the silane coupling agent or an organosilicon compound such as silicone oil is treated in the gas phase in order to improve the hydrophobicity and adjust the charge amount. You can

As the silane coupling agent that can be used in this case, fluorosilane, aminosilane, polydimethylsiloxane, methylhydrogenpolysiloxane and the like can be used in addition to those mentioned above.

[Particle Diameter of Toner Particles] The toner of the present invention preferably has a number average particle diameter of 2 to 8 μm, more preferably 3 to 6 μm. This particle size is
In the toner production method, it can be controlled by the concentration of the aggregating agent (salting out agent), the addition amount of the organic solvent, the fusing time, and the composition of the polymer.

The toner particles are particles obtained by adding an external additive to colored particles consisting of at least a binder resin and a colorant. The particle size and shape of the toner particles before and after the external additive are added. ,
No difference appears in the measured values. Therefore, what is called a colored particle to be exact may be called a toner particle.

By having the number average particle diameter of 2 to 8 μm, the number of toner fine particles having a large adhesive force which flies and adheres to the heating member to cause offset in the fixing step is reduced, and the transfer efficiency is increased. The image quality of halftone is improved, and the image quality of thin lines and dots is improved.

The number average particle size of the toner is as follows: Coulter Counter TA-II, Coulter Multisizer, SLAD
1100 (a laser diffraction particle size measuring device manufactured by Shimadzu Corporation) can be used for the measurement.

In the present invention, a Coulter Multisizer was used, and an interface (manufactured by Nikkaki Co., Ltd.) for outputting the particle size distribution and a personal computer were connected and used. As the aperture in the Coulter Multisizer, a 100 μm aperture was used, and the volume distribution of the toner of 2 μm or more (for example, 2 to 40 μm) was measured to calculate the particle size distribution and the average particle size.

[Image Forming Method] Next, an image forming apparatus used in the image forming method of the present invention will be described.

FIG. 1 is a sectional view showing an example of the image forming apparatus according to the present invention. Reference numeral 4 denotes a photosensitive drum which is a member to be charged, which is formed by forming an organic photoconductor (OPC) which is a photosensitive layer on an outer peripheral surface of a drum base made of aluminum, and rotates at a predetermined speed in an arrow direction. .

In FIG. 1, exposure light is emitted from the semiconductor laser light source 1 based on information read by a document reading device (not shown). This is distributed by the polygon mirror 2 in the direction perpendicular to the paper surface of FIG. 1, and is irradiated onto the surface of the photoconductor through the fθ lens 3 that corrects the image distortion to form an electrostatic latent image. The photoconductor drum 4 has a charger 5 in advance.
Are uniformly charged by and are rotated clockwise in accordance with the timing of image exposure.

The electrostatic latent image on the surface of the photosensitive drum is the developing device 6
The developed image formed by is transferred by the action of the transfer device 7 to the transfer paper 8 which has been conveyed at a timing. Further, the photosensitive drum 4 and the transfer paper 8 are separated by a separator (separation pole) 9, but the developed image is transferred and carried on the transfer paper 8 and guided to a fixing device 10 to be fixed.

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

The image forming apparatus according to the present invention may have a form in which a photosensitive drum and a process cartridge including at least one of a charging device, a developing device, a cleaning device, a recycling member and the like are mounted.

Next, the transfer paper is typically plain paper, but is not particularly limited as long as it can transfer the unfixed image after development, and of course, a PET base for OHP and the like are also included.

The cleaning blade 13 has a thickness of 1
A rubber-like elastic body of about 30 mm is used, and urethane rubber is most often used as the material. Since this is used in pressure contact with the photoconductor, it is easy to transfer heat. In the present invention, it is desirable to provide a releasing mechanism and keep it away from the photoconductor when the image forming operation is not performed.

The present invention can also be used in an image forming apparatus by electrophotography, particularly in an apparatus for forming an electrostatic latent image on a photosensitive member by a modulated beam modulated with digital image data from a computer or the like.

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

As a scanning optical system optically modulated by a digital image signal from a computer or a copy manuscript employed in this image forming method and apparatus, an acousto-optic modulator is interposed in a laser optical system, and the acousto-optic modulator is used to perform optical modulation. There is a device for modulating and a device for directly modulating the laser intensity by using a semiconductor laser. These scanning optical systems perform spot exposure on a uniformly charged photoconductor to form a dot-shaped image.

The beam emitted from the above-mentioned scanning optical system has a circular or elliptical luminance distribution which has a skirt spreading to the left and right and approximates a normal distribution. For example, in the case of a laser beam, it is usually the main beam on the photoconductor. One or both of the scanning direction and the sub-scanning direction is an extremely narrow round or elliptical shape of 20 to 100 μm.

(Fixing Device) The toner of the present invention passes a transfer paper (image forming support) on which a toner image is formed between a heating roller and a pressure roller which constitute a fixing device (fixing device). It is preferably used for an image forming method including a step of fixing the toner. The fixing device may be of a contact heating type, that is, a heating belt type or the like other than the type using a heating roller as long as the heating source directly contacts the transfer paper carrying the toner.

FIG. 2 is a schematic sectional view showing an example of a fixing device used in the image forming method using the toner of the present invention. The fixing device shown in FIG. 2 includes a heating roller 70 and a pressure roller 72 that is in contact with the heating roller 70. In addition,
In FIG. 2, T is a toner image formed on the transfer paper.

The heating roller 70 has a coating layer 82 made of a fluororesin or an elastic material formed on the surface of a cored bar 81, and includes a heating member 75 made of a linear heater.

The core metal 81 is made of metal and has an inner diameter of 10 to 70 mm. The metal forming the core metal 81 is not particularly limited, but examples thereof include metals such as iron, aluminum and copper, and alloys thereof.

The core metal 81 has a wall thickness of 0.1 to 15 mm, and is determined in consideration of a balance between energy saving requirements (thinning) and strength (depending on constituent materials). For example,
In order for the core metal made of aluminum to maintain the same strength as the core metal made of iron of 0.57 mm, it is necessary to make the wall thickness 0.8 mm.

The fluororesin constituting the coating layer 82 includes PTFE (polytetrafluoroethylene) and P.
FA (tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer) etc. can be illustrated.

The thickness of the coating layer 82 made of fluororesin is 1
The thickness is 0 to 500 μm, and preferably 20 to 400 μm.

The coating layer 82 made of fluororesin has a thickness of 1
When the thickness is less than 0 μm, the function as the coating layer cannot be sufficiently exhibited, and the durability as the fixing device cannot be ensured. On the other hand, there is a problem in that the surface of the coating layer having a thickness of more than 500 μm is easily scratched by paper dust, and toner or the like adheres to the scratched portion, resulting in image stain.

As the elastic body forming the coating layer 82, it is preferable to use silicone rubber such as LTV, RTV, HTV, etc. having good heat resistance and silicone sponge rubber.

Asker C, which is an elastic material constituting the coating layer 82
The hardness is less than 80 °, preferably less than 60 °.

The thickness of the cover layer 82 made of an elastic material is 0.1 to 30 mm, preferably 0.1 to 20 mm.
It is said that

Asker C, which is an elastic material constituting the coating layer 82
When the hardness exceeds 80 ° and the thickness of the coating layer 82 is less than 0.1 mm, the fixing nip cannot be increased, and the effect of soft fixing (for example, smoothed interface Effect of improving color reproducibility by toner layer)
Can't exert.

As the heating member 75, a halogen heater can be preferably used. The pressure roller 72 is
A coating layer 84 made of an elastic body is formed on the surface of the cored bar 83. The elastic body forming the coating layer 84 is not particularly limited, and various soft rubbers such as urethane rubber and silicone rubber and sponge rubber can be exemplified. The silicone rubber exemplified as the material forming the coating layer 82 and It is preferable to use silicone sponge rubber.

Asker C, which is an elastic material forming the coating layer 84
The hardness is less than 80 °, preferably less than 70 °, and more preferably less than 60 °.

The thickness of the coating layer 84 is 0.1 to 30 m.
m, preferably 0.1 to 20 mm.

Asker C, which is an elastic material constituting the coating layer 84
If the hardness exceeds 80 ° and the thickness of the coating layer 84 is less than 0.1 mm, the fixing nip cannot be increased and the soft fixing effect cannot be exhibited.

The material constituting the cored bar 83 is not particularly limited, but a metal such as aluminum, iron, copper or an alloy thereof can be used.

The contact load (total load) between the heating roller 70 and the pressure roller 72 is usually 40 to 350 N, preferably 50 to 300 N, and more preferably 50.
~ 250N. This contact load is applied to the heating roller 7
The strength is defined as 0 (thickness of the core metal 81), and for a heating roller having a core metal of, for example, 0.3 mm iron, it is preferably 250 N or less.

From the viewpoint of offset resistance and fixing property, the nip width is preferably 4 to 10 mm, and the surface pressure of the nip is 0.6 × 10 ^{5 to} 1.5 × 1.
It is preferably 0 ⁵ Pa.

As an example of the fixing conditions by the fixing device shown in FIG. 2, the fixing temperature (the surface temperature of the heating roller 70) is 150 to 210 ° C., and the fixing linear velocity is 80 to 640 mm.
/ Sec.

The fixing device used in the present invention may not be provided with a cleaning mechanism. That is, it is not necessary to use a pad, roller, web or the like impregnated with silicone oil for supplying the silicone oil to the upper roller (heating roller) of the fixing unit.

[0173]

EXAMPLES Examples of typical embodiments of the present invention are shown below,
The relationship between the configuration and the effect will be described. However, of course, the present invention is not limited to this.

Example 1 Production Example of Colored Particles 1 (Polymerization) In a flask equipped with a stirrer, 249 g of styrene, 88.2 g of n-butyl acrylate,
Methacrylic acid 19.4 g, n-octyl-3-mercaptopropionic acid ester (NOMP Mw: 218.3)
5) 3.61 g, α-methylstyrene dimer (Mw:
236.34) To a monomer mixed solution consisting of 3.91 g, 77 g of a compound represented by the above exemplified compound 19) (hereinafter, referred to as “exemplified compound (19)”) was added as a release agent, and 90 A monomer solution was prepared by heating at 0 ° C. and dissolving.

On the other hand, an anionic surfactant (the following formula (1
01)) 1 g of ion-exchanged water dissolved in 1560 ml of a surfactant solution is heated to 98 ° C., and a mechanical dispersing machine “CLEARMIX” having a circulation path is provided.
(Manufactured by M-Technique Co., Ltd.), the exemplified compound (1
The monomer solution of 9) was mixed and dispersed for 8 hours to prepare a dispersion liquid (emulsion liquid) containing emulsified particles (oil droplets) having a dispersed particle diameter (284 nm).

Then, to this dispersion (emulsion) was added an initiator solution prepared by dissolving 6.8 g of a polymerization initiator (KPS) in 265 ml of ion-exchanged water, and the system was heated at 98 ° C. for 12 hours.
Polymerization was performed by heating and stirring over time to obtain a latex.

(101) C ₁₀ H ₂₁ (OCH ₂ CH ₂ ) ₂
OSO ₃ Na (dispersion of colorant) 90 g of anio surfactant (101)
Was dissolved in 1600 ml of ion-exchanged water with stirring. While stirring this solution, carbon black (Regal 330
R: made by Cabot Co., Ltd.) (400.0 g) is gradually added, and a dispersion liquid of colorant particles (hereinafter, referred to as “colored” Agent Dispersion Liquid 1 ") was prepared. The particle size of the colorant particles in this colorant dispersion 1 was measured by using an electrophoretic light scattering photometer “ELS-800” (manufactured by Otsuka Electronics Co., Ltd.) and found to be 110 nm.

(Coagulation / fusion) 300 g of latex (in terms of solid content), 640 g of ion-exchanged water and 142 g of "colorant dispersion 1" were attached to a temperature sensor, a cooling pipe, a nitrogen introducing device, and a stirring device. Container (four-necked flask)
And stirred. After adjusting the temperature in the container to 30 ℃,
A 5 mol / L sodium hydroxide aqueous solution was added to this solution to adjust the pH to 8 to 11.0.

Then, magnesium chloride hexahydrate 8.
An aqueous solution prepared by dissolving 6 g in 1000 ml of ion-exchanged water,
With stirring, the mixture was added at 30 ° C. for 10 minutes. After standing for 3 minutes, the temperature starts to increase and the system is heated for 90 minutes to 90
The temperature was raised to ° C. In that state, the particle size of the associated particles was measured with "Coulter Counter TA-II", and when the number average particle size reached 4 to 7 µm, sodium chloride 28.5
An aqueous solution obtained by dissolving g in ion-exchanged water (1000 ml) was added to stop grain growth, and as a maturing treatment, heating and stirring were continued for 6 hours at a liquid temperature of 98 ° C. to continue fusion. The produced particles were filtered, washed repeatedly with ion-exchanged water at 45 ° C., and then dried with warm air at 40 ° C. to obtain colored particles 1.

Production Example of Colored Particle 2 In the production example of Colored Particle 1, 1-dodecanethiol (Mw: 202.4) 3.35 was used as the chain transfer agent in the polymerization step.
g, and colored particles 2 were obtained in the same manner except that the amount of α-methylstyrene dimer was changed to 3.91 g.

Production Example of Colored Particle 3 In the same manner as in the production example of Colored Particle 1, the chain transfer agent in the polymerization step was changed to 2.01 g of 1-dodecanethiol and the amount of α-methylstyrene dimer was changed to 5.48 g. The colored particles 3 were obtained.

Production Example of Colored Particle 4 In the same manner as in Production Example of Colored Particle 1, except that the chain transfer agent in the polymerization step was changed to 4.69 g of 1-dodecanethiol and the amount of α-methylstyrene dimer was changed to 2.35 g, the same procedure was performed. The colored particles 4 were obtained.

Production Example of Colored Particle 5 In the same manner as in Production Example of Colored Particle 1, except that the chain transfer agent in the polymerization step was changed to 0.67 g of 1-dodecanethiol and the amount of α-methylstyrene dimer was changed to 7.04 g, the same procedure was carried out. Thus, colored particles 5 were obtained.

Production Example of Colored Particle 6 In the same manner as in the production example of Colored Particle 1, the chain transfer agent in the polymerization step was changed to 6.03 g of 1-dodecanethiol and the amount of α-methylstyrene dimer was changed to 0.78 g. Thus, colored particles 6 were obtained.

Production Example of Colored Particle 7 In the production example of Colored Particle 1, 1.49 g of 1-butanethiol (Mw: 90.19) was used as the chain transfer agent in the polymerization step.
1.26 g of 2-propanethiol (Mw: 76.16)
Colored particles 7 were obtained in the same manner except that the above was changed to.

Production Example of Colored Particle 8 Colored particle 8 was produced in the same manner as in Production Example of colored particle 1 except that the chain transfer agent in the polymerization step was changed to 3.35 g of 1-dodecanethiol and 1.26 g of 2-propanethiol. Got 8.

Production Example of Colored Particle 9 In the production example of Colored Particle 1, 0.34 g of 1-dodecanethiol (0.05 mol) was used as the chain transfer agent in the polymerization step.
%), 7.43 g of α-methylstyrene dimer (0.9
Colored particles 9 were obtained in the same manner except that the content was changed to 5 mol%).

Production Example of Colored Particle 10 In the production example of Colored Particle 1, the chain transfer agent in the polymerization step was 6.37 g (0.95 mol) of 1-dodecanethiol.
%), 0.39 g of α-methylstyrene dimer (0.0
5 mol%), except that the color particles 10
Got

Production Example of Colored Particle 11 In the production example of Colored Particle 1, the chain transfer agent in the polymerization step was 4.0 g (0.5 mol%) of ethyl dithiodiacetate, 1-
Colored particles 11 were obtained in the same manner except that the content of butanethiol was changed to 1.5 g (0.5 mol%).

Production Example of Colored Particle 12 In the production example of Colored Particle 1, 6.2 g of bis (dimethylthiocarbamoyl) disulfide was used as the chain transfer agent in the polymerization step.
(1.0 mol%), di-n-butyl disulfide 4.84 g
Colored particles 12 were obtained in the same manner except that the content was changed to (1.0 mol%).

Production Example of Comparative Colored Particle 1 In the production example of Colored Particle 1, the same procedure as in Production Example of Colored Particle 1 was performed except that the chain transfer agent in the polymerization step was changed to n-octyl-3-mercaptopropionic acid ester (NOMP) amount of 7.23 g. Thus, comparative colored particle 1 was obtained.

Production Example of Comparative Colored Particle 2 In the production example of Colored Particle 1, the chain transfer agent in the polymerization step was changed to n-octyl-3-mercaptopropionic acid ester amount of 3.61 g and 1-dodecanethiol to 3.35 g. Comparative colored particles 2 were obtained in the same manner except that they were changed.

Production Example of Comparative Colored Particle 3 In the same manner as in Production Example of Colored Particle 1, except that the chain transfer agent in the polymerization step was changed to 2.52 g of 2-propanethiol and 4.84 g of di-n-butyl disulfide. Thus, comparative colored particles 3 were obtained.

Production Example of Comparative Colored Particle 4 In the production example of Colored Particle 1, the chain transfer agent in the polymerization step was 6.8 g (1.0 mol%) of p-methyl-allylbenzenethiolsulfonate and di-n disulfide. Comparative colored particles 4 were obtained in the same manner except that the amount of butyl was changed to 4.84 g (1.0 mol%).

In this Example, the polymerization was carried out only by one-step polymerization, but there may be a two-step or three-step polymerization step or a shelling step, at which time chain transfer is carried out in each polymerization reaction. The combination of agents may be the same or different.

[0196]

[Table 1]

Next, the above-mentioned colored particles 1 to 12 and comparative colored particles 1 to 4 are each made of hydrophobic silica (number average primary particle diameter = 12 nm,
1% by mass of hydrophobicity = 68) and 0.5% by mass of hydrophobic titanium oxide (number average primary particle size = 20 nm, hydrophobicity = 63) were added and mixed by a Henschel mixer to obtain a toner. These are designated as Toners 1 to 12 and Comparative Toners 1 to 4.

A volume average particle diameter of 60 μm obtained by coating the above toners 1 to 12 and comparative toners 1 to 4 with a silicone resin.
The above ferrite carrier was mixed to prepare a developer having a toner concentration of 6%. These are referred to as developers 1 to 12 and comparative developers 1 to 4.

Performance Evaluation Commercially available digital copying machine Konica Sitios Kon
ica7075 was used as an evaluation machine, and the heat roll fixing device was modified so that the heat roll temperature could be set arbitrarily.

Each of the developers 1 to 8 and the comparative developers 1 to 3 was loaded into an evaluation machine, and the following evaluations were carried out. Examples 1 to 12 and Comparative Example 1 were made corresponding to the respective developers. The results are shown in Table 2 as ~ 4.

The evaluation was carried out by setting the surface temperature of the fixing roller (upper roller) to 110 to 23 with respect to the unfixed image in which a solid black image having a width of 30 mm is formed by providing a 5 mm margin at the leading end of the transfer paper.
Fixing was performed while changing the temperature in increments of 10 ° C. up to 0 ° C., and the lower limit temperature at which fixing wrapping did not occur and the upper limit temperature at which fixing offset did not occur were examined. The fixing device is not provided with a cleaning mechanism.

The difference between the lower limit temperature and the upper limit temperature of the fixable temperature was set as the fixable temperature range, and the following evaluation was performed.

⊚ (excellent): Fixable temperature range is 100 ° C.
When there are more than ◯ (good): less than 100 ° C, 70 ° C or more (practical) × (bad): less than 70 ° C (impractical)

[0204]

[Table 2]

As is clear from Table 2, Examples 1 to 12 in the present invention are at least at a practical level, while
In Comparative Examples 1 to 4 other than the present invention, all of the characteristics that are practically problematic can be obtained.

[0206]

According to the present invention, in order to expand the non-offset region of the toner, it is possible to find a good ratio relationship of the chain transfer constants of the chain transfer agents when a plurality of chain transfer agents are used in the synthesis of the resin for the toner. I was able to. Further, it was possible to provide a toner for developing an electrostatic image using a resin having a small residual monomer and a broad molecular weight distribution, a method for producing the same, and an image forming method.

[Brief description of drawings]

FIG. 1 is a cross-sectional configuration diagram showing an example of an image forming apparatus according to the present invention.

FIG. 2 is a schematic cross-sectional view showing an example of a fixing device.

[Explanation of symbols]

1 Semiconductor laser light source 2 polygon mirror 3 fθ lens 4 photoconductor drum 5 charger 6 developer 7 Transfer device 8 Transfer paper 9 Separator (separation pole) 10 Fixing device 11 Cleaning device 12 Pre-charge exposure (PCL) 13 Cleaning blade

Claims (5)

[Claims] 1. A toner for developing an electrostatic charge image comprising a resin obtained by polymerizing a polymerizable monomer containing a chain transfer agent in an aqueous medium and a colorant, wherein the chain transfer agent is two kinds. The electrostatic charge image developing toner according to the above, wherein the ratio of the larger constant (TA) and the smaller constant (TB) of the chain transfer constants has the following relationship. 2 ≦ TA / TB ≦ 500 TA: Chain transfer constant of chain transfer agent A TB: Chain transfer constant of chain transfer agent B 2. The toner for developing an electrostatic charge image according to claim 1, wherein the residual monomer amount is 200 ppm or less. 3. The toner for developing an electrostatic image according to claim 1, wherein the ratio of the amount of the chain transfer agent A to the amount of the chain transfer agent B used is 1: 9 to 9: 1. 4. The method for producing the toner for developing an electrostatic charge image according to claim 1, wherein the polymerizable monomer is polymerized in an aqueous medium to prepare resin fine particles and colored. 1. A method for producing a toner for developing an electrostatic charge image, which comprises mixing with agent particles and salting out, aggregating and fusing them to obtain toner particles. 5. A step of forming an electrostatic charge image on an electrostatic charge image carrier, a step of developing the electrostatic charge image with a developer containing a toner for developing an electrostatic charge image to form a toner image, and a transfer of the toner image. An electrostatic charge image developing toner according to any one of claims 1 to 3, which is used as an electrostatic charge image developing toner in an image forming method including a step of transferring onto the body and a step of contact heating and fixing after transferring. An image forming method characterized by using.