JP5515213B2 - Method for producing colored polymer particles - Google Patents

Description

  The present invention relates to colored polymer particles suitable as a toner for use in electrophotography, electrostatic recording method, electrostatic printing method and the like, an efficient production method thereof, and a toner and a developer using the colored polymer particles The present invention relates to a process cartridge, an image forming apparatus, and an image forming method.

  A number of methods are known as electrophotographic methods (see Patent Documents 1 and 2). Generally, an electric latent image is formed on a photosensitive layer using a photoconductive substance by using various means. An electrostatic latent image forming process to be formed, a developing process in which toner is developed to form a toner image, a transfer process in which the toner image is transferred to a recording material such as paper, and the toner image transferred to the recording material is heated. , A fixing process for fixing to a recording material by pressure, thermal pressure, solvent vapor or the like, a cleaning process for removing toner remaining on the photoreceptor layer, and the like.

  The toner used in the electrophotographic method is required to be manufactured by a method that saves energy and has little influence on the environment. As a current toner production method, a melt kneading and pulverizing method is conventionally known, but in recent years, a chemical method in a liquid solvent (eg, emulsion polymerization method, suspension polymerization method, dispersion polymerization method, dissolution suspension method). Polymerization methods such as turbidity methods and dissolution suspension elongation methods) are becoming mainstream. The chemical toner produced by such a chemical method (polymerization method) effectively expresses the desired function as expressed by the names of capsule toner and core-shell toner from the viewpoint of environmental issues in recent years. What has a possible form is provided.

  In the toner production method by the melt kneading and pulverizing method, in order to ensure the uniformity of the shape of the obtained toner, it is important how to uniformly disperse and pulverize each constituent material. Basically, the shape of the pulverized toner is indeterminate, and the pulverized cross section is random. Therefore, it is very difficult to control the shape and structure. In addition, when many coloring materials, release agents, charge control agents, and the like are added, during the pulverization process, these added materials are easily exposed on the surface side by cleaving at the crystal plane, and within each particle. There is a problem that quality deterioration is likely to occur, such as toner characteristics such as fluidity and charging performance, such as uneven charging property.

  In addition, the selection range for toner materials is limited. That is, the resin colorant dispersion must be sufficiently brittle and pulverizable. However, when the resin colorant dispersion is sufficiently brittle, a particle group having a wide particle size range is likely to be formed when the dispersion is actually finely pulverized at a high speed. A new problem arises that finely pulverized particles are included in this particle group. Further, such a highly brittle material is not preferable because it is more susceptible to pulverization when actually used in a copying machine or the like.

On the other hand, in order to overcome the problems of the toner due to these pulverization methods, a suspension polymerization method (one of chemical toner production methods) such as that disclosed in Patent Document 3 has been proposed. In this suspension polymerization method, a polymerizable monomer, a colorant, a polymerization initiator, a charge control agent, etc. are dissolved or dispersed to form a monomer composition, which is further dispersed in water containing a dispersion stabilizer. By simultaneously performing polymerization, a toner having a desired particle size can be obtained.
However, the toner obtained by this method has a very wide particle size distribution and requires a classification step, so that the yield is drastically reduced. It is remarkable.

In order to remedy this problem, non-aqueous dispersion polymerization in which the vinyl monomer is soluble in the dispersion medium in which the vinyl monomer is soluble and the polymerized particles are insoluble in the presence of the pigment as in Patent Document 4 and Patent Document 5. The method by is proposed.
However, in this method, there is no contrivance for finely dispersing the pigment and compositing it into the polymerized particles, and the pigment aggregates in the polymerization system or is free from the polymerized particles. It was extremely difficult and impractical to encapsulate the pigment in the polymer particles. In order to solve this problem, in Patent Document 6, a pigment dispersion paste is prepared using a pigment and a pigment dispersant in a polymerizable monomer, and colored particles are obtained by dispersion polymerization of the pigment dispersion paste. Since a hydrophilic solvent is used, the colored particle surface becomes hydrophilic, and in the case of toner, there is a problem that charging rise, charge decrease under high temperature and high humidity, and charge fluctuation with time increase. There are also problems such as uneven coloring, low coloring power, the presence of free pigments, and a wide particle size distribution. Furthermore, it is difficult to obtain a desired toner polarity (plus or minus) by the pigment dispersant, and the actual situation is that a satisfactory toner has not been obtained so far.

Furthermore, although the chemical toner production method can produce a toner having a small particle size and a narrow particle size distribution as compared with the pulverization method, a large amount of waste liquid generated during production, a filtration step, and a drying step In addition to high costs, there are many issues that need to be solved in terms of environmental impact and resource saving.
In particular, conventional chemical toners are often granulated in water or in a hydrophilic solvent, so the toner surface is likely to be hydrophilic, resulting in deterioration of charging performance and destabilization of time and environmental characteristics. Serious problems such as transfer defects, toner scattering and image quality degradation are also induced.

As a method to solve these problems, supercritical fluids and subcritical fluids are dispersed instead of conventional water and organic solvents as a method that does not use organic solvents, does not generate waste water and waste liquid, and does not require drying energy. Patent Document 7 describes use as a solvent. By using a supercritical fluid or subcritical fluid as a dispersion solvent, the toner characteristics such as charging property, environmental property and stability over time are good, low cost, no waste liquid, and no drying process is required. In addition, it is possible to produce a toner that does not contain residual monomers and has a small environmental load.
In the conventional dispersion polymerization, when a colorant is added to the monomer in advance and reacted, there is a problem that a reaction failure occurs or polymer particles cannot be formed. Therefore, the polymer particles have been dyed later. Even when the above-mentioned supercritical fluid or subcritical fluid is used as a dispersion solvent, a colorant is added after the polymer particles are prepared. As a result, it is easy to obtain a toner with low coloring power (low image density) or a toner with poor weather resistance.

Therefore, compared to chemical toners manufactured by the conventional methods, toners having good basic toner characteristics such as image density, charging, aging and the like, and having no waste liquid, no drying process, low cost, and manufacturing methods thereof are still provided. The current situation is not.
US Pat. No. 2,297,691 Japanese Patent Publication No.42-23910 Japanese Patent Laid-Open No. 36-10231 JP-A 61-273552 JP-A-62-73276 Japanese Patent No. 2633383 JP 2007-047752 A

  An object of the present invention is to solve the above-described problems and achieve the following objects. That is, the present invention granulates colored polymer particles in a supercritical fluid or subcritical fluid with good yield, and manufactures colored polymer particles having excellent basic properties such as charging performance at low cost and low environmental impact. It is an object of the present invention to provide a toner, a developer, a process cartridge, an image forming apparatus, and an image forming method capable of improving the image quality using the colored polymer particles.

As a result of intensive studies in view of the above problems, the present inventors have obtained the following knowledge.
That is, colored polymer particles obtained by polymerizing a polymerizable monomer in a supercritical fluid or a subcritical fluid, or colored polymer particles obtained by dissolving or dispersing a toner binder resin and a pigment in the fluid. It has been found that chemical toner (polymerized toner) using particles can provide a toner production method having good toner characteristics such as charging performance, low cost, and low environmental load.
This time, by further conducting dispersion polymerization in a supercritical fluid or subcritical fluid, the pigment can be taken into the polymer particles without using a pigment dispersant as in Patent Document 6 (Patent No. 2633383). I also understood. As a result, the material cost and the manufacturing process can be shortened, and the toner chargeability, aging and environmental characteristics are good, and a low-cost manufacturing method can be provided. It was also found that in this method, the pigment can be uniformly colored at a high concentration without inhibiting the polymerization reaction.

  Among the supercritical fluids and subcritical fluids, supercritical carbon dioxide and subcritical carbon dioxide are nonflammable and highly safe, and behave as a hydrophobic solvent, so that the surface of the colored polymer particles becomes hydrophobic. Supercritical carbon dioxide and subcritical carbon dioxide are vaporized at normal temperature and normal pressure, so that they can be easily separated and recovered from colored polymer particles and reused. Furthermore, since the colored polymer particles are suddenly obtained in a dry state, there is no need for a drying step, a waste liquid treatment step, and no generation of waste liquid. It has been found that all the problems so far can be solved by using carbon.

The present invention is based on the above findings of the present inventors, and means for solving the above problems are as follows.
(1) A supercritical fluid or subcritical fluid that dissolves at least a radical polymerizable monomer but does not dissolve polymer particles obtained by polymerizing the radical polymerizable monomer, the radical polymerizable monomer, and a pigment. A method for producing colored polymer particles, wherein the radical polymerizable monomer is polymerized by a dispersion polymerization method in a pigment dispersion to obtain colored polymer particles insoluble in the supercritical fluid or subcritical fluid.
(2) The method for producing colored polymer particles according to (1), wherein the supercritical fluid or subcritical fluid is supercritical carbon dioxide or subcritical carbon dioxide.

(3) The pigment dispersion further contains a surfactant that functions as both a supercritical fluid or subcritical fluid and a radical polymerizable monomer, as described in (1) or (2) above Of producing colored polymer particles.

( 4 ) The coloring according to any one of (1) to ( 3 ), wherein the pigment dispersion further contains a releasing agent to obtain colored polymer particles containing the releasing agent. A method for producing polymer particles.

（式中、Ｒ₁は、水素原子もしくはメチル基、Ｒ₂はメチレン基もしくはエチレン基、Ｒfは、炭素数が７〜１０であるパーフルオロアルキル基を表す。） ( 5 ) The method for producing colored polymer particles according to (3) or (4) , wherein the surfactant has a partial structural formula represented by the following general formula (1).

(In the formula, R ₁ represents a hydrogen atom or a methyl group, R ₂ represents a methylene group or an ethylene group, and R f represents a perfluoroalkyl group having 7 to 10 carbon atoms.)

  According to the present invention, a supercritical fluid or subcritical fluid that dissolves at least a radical polymerizable monomer but does not dissolve polymer particles obtained by polymerizing the radical polymerizable monomer, the radical polymerizable monomer, and a pigment By polymerizing the radical polymerizable monomer in a pigment dispersion containing, polymer particles uniformly colored at a high concentration can be obtained without inhibiting the polymerization reaction. As a result, it is possible to provide a method for producing colored polymer particles at a low cost by reducing the material cost, shortening the production process, etc., and improving the chargeability, time-lapse and environmental characteristics.

  Among supercritical fluids and subcritical fluids, supercritical carbon dioxide and subcritical carbon dioxide are nonflammable and highly safe, and behave as a hydrophobic solvent, so that the surface of the colored polymer particles becomes hydrophobic. Supercritical carbon dioxide and subcritical carbon dioxide are vaporized at normal temperature and normal pressure, so that they can be easily separated and recovered from colored polymer particles and reused. Furthermore, since colored polymer particles are suddenly obtained in a dry state, there is no need for a drying step or a waste liquid treatment step. By using supercritical carbon dioxide or subcritical carbon dioxide, all the problems up to now can be solved at once. Can do. The toner using the colored polymer particles can provide a developer, a process cartridge, an image forming apparatus, and an image forming method that have good toner characteristics and can improve the image quality using the toner.

(Colored polymer particles and production method thereof)
The colored polymer particles of the present invention are obtained by the method for producing colored polymer particles of the present invention.
The method for producing colored polymer particles of the present invention includes at least polymerization of a radically polymerizable monomer and production of particles in a supercritical fluid or subcritical fluid, and other steps appropriately selected as necessary. including.
Hereinafter, details of the colored polymer particles and toner of the present invention will be clarified through the description of the method for producing colored polymer particles of the present invention.

<Polymerization process in supercritical fluid>
A pigment dispersion containing a supercritical fluid or subcritical fluid that dissolves at least a radical polymerizable monomer but does not dissolve polymer particles obtained by polymerizing the radical polymerizable monomer, the radical polymerizable monomer, and a pigment A process for producing colored polymer particles by dispersing and polymerizing the radical polymerizable monomer therein will be described. As a method of producing colored polymer particles using a supercritical fluid or subcritical fluid, dispersion polymerization can take advantage of the advantage of using a supercritical fluid or subcritical fluid. It is superior to suspension polymerization and emulsion polymerization in terms of narrow distribution.

In the dispersion polymerization method in a supercritical fluid, a supercritical fluid that dissolves in the supercritical fluid or a surfactant that functions as both a subcritical fluid and a radical polymerizable monomer is used. Is dissolved, but the resulting polymer is swollen or hardly dissolved in the supercritical fluid, and is insoluble in one or more radically polymerizable monomers such as vinyl monomers and the supercritical fluid. The pigment is used. Further, it includes a reaction in which a radical polymerizable monomer is reacted and grown in the above-mentioned system using a polymer having a particle size distribution narrower than the target particle diameter in advance. The radical polymerizable monomer used for the growth reaction may be the same radical polymerizable monomer as that used to produce the seed particles or another radical polymerizable monomer, but the polymer is dissolved in the supercritical fluid. should not be done. By returning the polymer supercritical dispersion obtained by this method to normal temperature and pressure, dried colored polymer particles can be obtained.
As a method of polymerizing a pigment dispersion comprising at least the supercritical fluid or subcritical fluid, a pigment and a radical polymerizable monomer, a dispersion in which the pigment is dispersed in the supercritical fluid or subcritical fluid is prepared. A radically polymerizable monomer is added to form a pigment dispersion and polymerized, and a radically polymerizable monomer composition containing a pigment and a radically polymerizable monomer is prepared, and this is supercritical. Examples thereof include a method of polymerizing by dispersing in a fluid or subcritical fluid to obtain a pigment dispersion.
The surfactant may be added to the supercritical fluid or subcritical fluid, but may be added to the radical polymerizable monomer composition.

A surfactant that functions as both a supercritical fluid or subcritical fluid and a radical polymerizable monomer is a surfactant that has affinity for both the supercritical fluid or subcritical fluid and the radical polymerizable monomer. For example, when supercritical carbon dioxide is used as the supercritical fluid, it means a surfactant having a parent CO ₂ group and a parent monomer group in one molecule. In this case, the parent CO ₂ group is not particularly limited, and examples thereof include a perfluoroalkyl group, a polydimethylsiloxane group, an ether group, and a carbonyl group. The parent monomer group is not particularly limited as long as it is a group having affinity for the radical polymerizable monomer to be used, but is preferably synthesized from the monomer to be used (radical polymerizable monomer). Polymer chain.

  Surfactants that function as both supercritical fluids or subcritical fluids and radical polymerizable monomers are used to produce supercritical fluids or subcritical fluids to be used, target polymer particles and seed particles, or grown particles. However, it has a high affinity and adsorbability to the surface of the polymer particles, especially in the sense of sterically preventing the coalescence of the polymer particles, and also has an affinity and solubility in the supercritical fluid. The higher one is chosen. Further, in order to enhance the repulsion between particles in a three-dimensional manner, a molecular chain having a certain length, preferably a molecular weight of 10,000 or more is selected. However, if the molecular weight is too high, the viscosity of the liquid is remarkably increased, the operability and the stirrability are deteriorated, and the precipitation probability of the produced polymer on the particle surface varies. In addition, the presence of the surfactants listed above in advance in the radical polymerizable monomer is also effective for stabilization.

The amount of the surfactant used varies depending on the type of the radically polymerizable monomer for forming the target polymer particles, but is more preferably 0.1 to 10% by mass with respect to the supercritical fluid and subcritical fluid. 1-5 mass% is preferable. When the concentration of the surfactant is low, the polymer particles produced have a relatively large diameter, and when the concentration is high, small particles are obtained. There is little effect on.
In addition, even if inorganic compound fine powder is used in combination with these surfactants, the stabilization of the produced polymer particles and the improvement of the particle size distribution can be further enhanced. Polymerization may be carried out in the presence of a radically polymerizable monomer composition or seed particle dispersion added for the purpose of preventing the above.

Initially generated particles are stabilized in the supercritical fluid or subcritical fluid by the distributed surfactant that is equilibrated to the polymer particle surface, but the unreacted radical polymerizable monomer is supercritical fluid. If it is present in a considerable amount, it is somewhat swollen and sticky, and the steric repulsive force of the surfactant is overcome and agglomerates.
Furthermore, when the amount of the radical polymerizable monomer is extremely large relative to the supercritical fluid or subcritical fluid, the produced polymer is completely dissolved, and does not precipitate unless the polymerization proceeds to some extent. The state of precipitation in this case takes the form of forming a highly sticky lump. Therefore, the amount of the monomer to the supercritical fluid or subcritical fluid when the particles are produced is naturally limited, and varies slightly depending on the type of the supercritical fluid or subcritical fluid, but is approximately 100% by mass or less, preferably Is suitably 80% by mass or less.

  In the present invention, a polymerization initiator can be used. As the polymerization initiator to be used, a normal radical initiator is used. For example, azo series such as 2,2'-azobisisobutyronitrile (AIBN), 2,2'-azobis (2,4-dimethylvaleronitrile), 1,1'-azobis (cyclohexane-1-carbonitrile) Polymerization initiators such as lauryl peroxide, benzoyl peroxide, tert-butyl peroxide, methyl ethyl ketone peroxide, isopropyl peroxycarbonate, cumene hydroperoxide, 2,4-dichlorobenzoyl peroxide, potassium persulfate, etc. An oxide initiator or a system in which sodium thiosulfate, amine, or the like is used in combination is used. The polymerization initiator concentration is preferably 0.1 to 10 parts by mass with respect to 100 parts by mass of the radical polymerizable monomer.

For polymerization, for example, a surfactant is completely dissolved in a supercritical fluid or subcritical fluid, and then a radical polymerizable monomer containing a pigment, one or more radical polymerizable monomers, a polymerization initiator, and the like. The body composition is added, a pigment dispersion is prepared, and the mixture is heated at a temperature corresponding to the decomposition rate of the used polymerization initiator while stirring at a speed that makes the flow in the reaction vessel uniform. Generally, 40 to 100 ° C. is preferable. 50 to 85 degreeC is especially good.
In addition, since the temperature at the initial stage of polymerization has a large effect on the particle size to be generated, it is better to raise the temperature to the polymerization temperature after adding the radical polymerizable monomer and dissolve the initiator in a small amount of supercritical fluid. desirable. In the polymerization, it is necessary to sufficiently expel oxygen in the reaction vessel with an inert gas such as nitrogen gas, argon gas or oxygen dioxide gas. If the oxygen purge is insufficient, fine particles are likely to be generated.

In order to carry out the polymerization in a high polymerization rate region, a polymerization time of 5 to 72 hours is required. However, the polymerization is stopped in a desired particle size and particle size distribution state, or a polymerization initiator is sequentially added. Alternatively, the polymerization rate can be increased by carrying out the reaction under high pressure.
Alternatively, the polymerization may be carried out in the presence of a compound having a large chain transfer constant for the purpose of adjusting the average molecular weight. For example, a low molecular compound having a mercapto group, carbon tetrachloride, carbon tetrabromide and the like. Other preferably used are halogenated hydrocarbons such as ethyl dibromide acetate ethyl tribromide acetate, ethyl dibromide benzene, ethane dibromide, ethane dichloride, diazothioether, benzene, ethylbenzene, isopropylbenzene, etc. Hydrocarbon, tertiary dodecyl mercaptan; mercaptans such as n-dodecyl mercaptan, disulfides such as diisopropyl xanthogen disulfide, thioglycolic acid, 2-ethylhexyl thioglycolate, butyl thioglycolate, methoxybutyl thioglycolate, trimethylol Examples thereof include propanetris- (thioglycolate), thioglycolic acid derivatives such as ammonium thioglycolate, thioglycerol, and the like.

The amount of the chain transfer agent used can be 10 ⁻³ to 10 mass% with respect to the radical polymerizable monomer. In particular, when a chain transfer agent is present before the start of the polymer, the size of the precipitated core particles can be controlled by adjusting the molecular weight of the polymer that is initially formed.
Moreover, when adding after depositing the core particles, the molecular weight of the polymer particles to be produced can be adjusted, and the flow characteristics when melted by the desired heat can be obtained.

  Further, in the dispersion polymerization of the present invention, in order to control the melt viscosity of the toner that has come out, the following crosslinking agent may be added to carry out dispersion polymerization to produce a crosslinked polymer. Examples of such crosslinking agents include divinylbenzene, divinylnaphthalene, divinyl ether, divinyl sulfone, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, ethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, diethylene glycol diacrylate, and triethylene glycol diacrylate. 1,3-butylene glycol dimethacrylate, 1,6-hexane glycol dimethacrylate, neopentyl glycol dimethacrylate, dipropylene glycol dimethacrylate, polypropylene glycol dimethacrylate, 2,2'-bis (4-methacryloxydiethoxyphenyl) Propane, 2,2'-bis (4-acryloxydiethoxyphenyl) propa , Trimethylolpropane trimethacrylate, trimethylol propane triacrylate, tetra methylol methane tetraacrylate, dibromo neopentyl glycol dimethacrylate, etc. diallyl phthalate, a general crosslinking agent can be used Tekisen.

The generated colored polymer particles can be used as toner base particles. For example, an external additive can be added to the colored polymer particles to obtain a toner.
Further, in order to use the colored polymer particles as a magnetic toner, magnetic powder may be added as an additive. As such magnetic powder, a substance that is magnetized by being placed in a magnetic field is used, and examples thereof include powders of ferromagnetic metals such as iron, cobalt, and nickel, and compounds such as magnetite, hematite, and ferrite.
Other components that can be contained in the toner are not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include inorganic fine particles, a charge control agent, a fluidity improver, and a cleaning property improver. .

  The weight average molecular weight of the generated colored polymer particles (toner base particles) is not particularly limited and may be appropriately selected depending on the intended purpose. For example, it is preferably 1,000 or more, and 2,000 to 10,000. Is more preferable, and 3,000 to 1,000,000 is particularly preferable. When the weight average molecular weight is less than 1,000, the hot offset resistance may be deteriorated.

  The glass transition temperature (Tg) of the colored polymer particles (toner base particles) to be produced is not particularly limited and may be appropriately selected depending on the intended purpose. For example, 30 to 70 ° C. is preferable, and 40 to 65 ° C. Is more preferable. When the glass transition temperature (Tg) is less than 30 ° C., the heat-resistant storage stability of the toner may deteriorate, and when it exceeds 70 ° C., the low-temperature fixability may not be sufficient.

-Supercritical fluid and subcritical fluid-
The supercritical fluid exists as a non-condensable high-density fluid in a temperature / pressure region that exceeds the limit (critical point) where gas and liquid can coexist, does not cause condensation even when compressed, and exceeds the critical temperature. And, it is a fluid that is in a state of a critical pressure or higher, at least the radical polymerizable monomer is dissolved, but there is no particular limitation as long as the polymerized particles obtained by polymerizing the radical polymerizable monomer are not dissolved, Although it can be appropriately selected according to the purpose, one having a low critical temperature is preferable, and the subcritical fluid exists as a high-pressure liquid in a temperature / pressure region near the critical point, and is at least a radically polymerizable monomer. The polymer is dissolved, but there is no particular limitation as long as the polymerized particles obtained by polymerizing the radical polymerizable monomer are not dissolved, and can be appropriately selected according to the purpose. Preferred examples of the supercritical fluid and subcritical fluid include carbon monoxide, carbon dioxide, dinitrogen monoxide, nitrogen, methane, ethane, propane, 2,3-dimethylbutane, and ethylene. It selects suitably according to a polymerizable monomer. Among these, carbon dioxide can easily create a supercritical state with a critical pressure of 7.3 MPa and a critical temperature of 31 ° C., does not generate waste liquid, does not require a drying process, is nonflammable and easy to handle, and has hydrophobic toner characteristics. Is particularly preferable in that it is good.
What was mentioned as said supercritical fluid can be used conveniently also as said subcritical fluid. The supercritical fluid and the subcritical fluid may be used singly or in combination of two or more.

  The critical temperature and critical pressure of the supercritical fluid and subcritical fluid are not particularly limited and may be appropriately selected according to the purpose. The critical temperature is −200 to 200 ° C., preferably -100-150 degreeC, More preferably, it is 0-100 degreeC.

  Furthermore, in addition to the supercritical fluid and the subcritical fluid, an organic solvent can also be used as an entrainer. By adding an entrainer, it is possible to control the solubility and the degree of plasticization of the colored polymer particle constituent material in the supercritical fluid. The organic solvent is not particularly limited as long as it does not dissolve the toner resin under normal temperature and normal pressure (25 ° C., 0.1 MPa), and can be appropriately selected according to the purpose. For example, methanol, ethanol, propanol Ammonia, melamine, urea, thioethylene glycol and the like. The addition amount of the entrainer is 0.1 mass% to 10 mass%, preferably 0.5 mass% to 5 mass%.

-Radically polymerizable monomer-
The radical polymerizable monomer is not particularly limited as long as the polymer component obtained by polymerization is a resin used for forming an image as a binder resin for toner, and is appropriately selected according to the purpose. For example, radically polymerizable monomers having an unsaturated double bond represented by vinyl monomers can be mentioned, and a wide variety of them are commercially available.
For example, styrene compounds such as styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, p-methoxystyrene, p-ethylstyrene; methyl acrylate, ethyl acrylate, propyl acrylate, n-butyl acrylate, isobutyl acrylate, n-octyl acrylate, dodecyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, phenyl acrylate, dimethylaminoethyl acrylate, diethylaminoethyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, Dodecyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate Over DOO, phenyl methacrylate, dimethylaminoethyl methacrylate, methacrylic acid esters such as diethylaminoethyl methacrylate; acrylonitrile; methacrylonitrile; acrylamide and the like.

-Surfactant-
Surfactants that function as both supercritical fluids or subcritical fluids and radical polymerizable monomers include fluorine group-containing vinyl monomers, homopolymers obtained by polymerizing fluorine group-containing vinyl monomers, fluorine group-containing vinyl monomers, and other monomers. Examples thereof include a copolymer with a vinyl monomer. Examples of the fluorine group-containing vinyl monomer include acrylate monomers and methacrylate monomers having a perfluoroalkyl group. Many of these fluorine group-containing vinyl monomers are commercially available (for example, fluorine compound catalogs from AMAX Co., etc.) and can be used as appropriate according to the purpose.

As the surfactant, those having a partial structural formula represented by the general formula (1) are preferable, but R ₁ in the general formula (1) is not limited to a hydrogen atom and a methyl group, but also a carbon atom. number 2-4 lower alkyl groups (e.g. ethyl, propyl, isopropyl, n- butyl group, sec- butyl group, tert- and butyl group), for R ₂ include a methylene group, other ethylene group In addition, an alkylene group (for example, a propylene group, an isopropylene group, a 2-hydroxypropyl group, a butylene group, a 2-hydroxybutylene group, etc.), and the Rf group has a carbon number of 1 to Examples thereof include 6 and perfluoroalkyl groups having 11 to 20 carbon atoms.
As a general method for producing a fluorine-containing surfactant, it is synthesized by polymerizing a fluorine-containing vinyl monomer in a fluorinated solvent such as HCFC225. Instead of HCFC225, supercritical carbon dioxide is used as a reaction solvent. It is desirable to use what is synthesized by using as a point that environmental load can be reduced.

In addition, bulk polymerization and living radical polymerization can be given as examples of other methods for synthesizing a fluorine-containing surfactant. The bulk polymerization and living radical polymerization will be described below.
Bulk polymerization is a thermal radical generated by heating a monomer composition comprising a polymerizable monomer in a reaction vessel in an inert gas atmosphere such as nitrogen under reduced pressure, or normal pressure or increased pressure, and / or A known radical polymerization initiator such as 2,2′-azobisisobutyronitrile (hereinafter abbreviated as AIBN), benzoyl peroxide or the like is added to the monomer composition, and the polymerization initiator is used. Initiated by the generated radical. Examples of the radical polymerization initiator include benzoyl peroxide, 2,4-dichlorobenzoyl peroxide, p-chlorobenzoyl peroxide, o-methylbenzoyl peroxide, bis-3,5,5-trimethylcyclohexanol peroxide, and the like. Diacyl peroxide, dicumyl peroxide, 2,5-dimethyl-2,5-di- (t-butylperoxy) hexane, t-butylcumyl peroxide, di-t-butyl peroxide, 1,3- Dialkyl peroxides such as bis- (t-butylperoxyisopropyl) benzene, peroxyketals such as 1,1-di- (t-butylperoxy) cyclohexane, alkyl peresters such as t-butylperoxybenzoate, diisopropyl Peroxy dicarbo Organic peroxides such as carbonates such as carbonates, 2,2′-azobis-isobutyronitrile, 2,2′-azobis-2,4-dimethylvaleronitrile, 2,2′-azobiscyclohexylnitrile, Examples thereof include azo compounds such as 1,1′-azobis (cyclohexane-1-carbonitrile) and 2-phenylazo-4-methoxy-2,4-dimethylvaleronitrile. These may be used alone or in combination of two or more. If the amount of the radical polymerization initiator added is small, it is hardly used in the initial stage of polymerization and the polymerization is difficult to complete.If the amount is increased, the amount of radical generation increases and it becomes difficult to obtain a polymer having a sufficient molecular weight. Preferably it is 0.01-2 mass parts with respect to 100 mass parts of monomers, More preferably, it is 0.01-1.5 mass parts. Moreover, the polymerization temperature in this case is 50-220 degreeC normally, Preferably it is 80-150 degreeC.

  Furthermore, in the above bulk polymerization, the molecular weight of the resulting polymer can be adjusted by adding a chain transfer agent. Any chain transfer agent may be used as long as it is usually used for polymerization or copolymerization of radical polymerizable monomers. For example, mercaptans such as methyl mercaptan, t-butyl mercaptan, decyl mercaptan, benzyl mercaptan, lauryl mercaptan, stearyl mercaptan, n-dodecyl mercaptan, t-dodecyl mercaptan, mercaptoacetic acid, mercaptopropionic acid, etc .; methanol, propanol, butanol, iso Examples include alcohols such as butanol, t-butanol, hexanol, benzyl alcohol, and allyl alcohol; halogenated hydrocarbons such as chloroethane, fluoroethane, trichloroethylene, and carbon tetrachloride. Among them, mercaptans are preferable, and n-dodecyl mercaptan (hereinafter abbreviated as n-DM) is more preferable. This chain transfer agent may be charged all at once into the reaction vessel before polymerization, or may be added continuously or sequentially during the polymerization.

The amount of the chain transfer agent in the present invention is usually 0.01 to 1 part by mass, preferably 0.05 to 0.5 part by mass with respect to 100 parts by mass of the polymerizable monomer. If this amount is less than 0.01 parts by mass, the viscosity of the polymerization system becomes high, which makes it difficult to produce. On the other hand, when this amount exceeds 1 part by mass, the molecular weight of the resulting polymer is lowered.
As a method for stopping the polymerization, any known method may be used as long as the chain transfer of the growing radical stops and disappears. For this purpose, 50 to 5,000 ppm of a polymerization terminator is added to the polymerization solution, oxygen or air is blown into the polymerization solution, the polymerization solution is cooled to 40 ° C. or less, and these may be used alone or in combination. They can be combined.

  A polymerization terminator is a chemical that reacts quickly with radicals generated from polymerizable monomers and / or polymerization initiators and converts them into stable radicals or neutral substances that do not subsequently cause polymerization. . Specific examples thereof include quinones such as p-benzoquinone, naphthoquinone, phenanthraquinone, 2,5-diphenyl-p-benzoquinone; hydroquinone, pt-butylcatechol, 2,5-di-t-butylhydroquinone. Hydroquinones such as mono-t-butylhydroquinone and 2,5-di-t-butylhydroquinone; phenols such as di-t-butyl paracresol hydroquinone monomethyl ether and α-naphthol; organics such as copper naphthenate Inorganic copper salts; Amidines such as acetamidine acetate and acetamidine sulfate; Hydrazine salts such as phenylhydrazine hydrochloride and hydrazine hydrochloride; Trimethylbenzylammonium chloride, Laurylpyridinium chloride, Cetyltrimethylammonium chloride, Phenyltrimethyla Quaternary ammonium salts such as Moniumukurorido; pyrogallol, tannic acid, polyhydric phenols resorcinol and the like; nitro compounds, oximes and the like.

  The living radical polymerization method preferably uses two living radical polymerization methods, a TEMPO (2,2,6,6-tetramethylpiperidinyl-1-oxy) method and an iodine transfer polymerization method. For the TEMPO (2,2,6,6-tetramethylpiperidinyl-1-oxy) method, see M.M. K. Trends Polym. By Georges et al. Sci. Vol. 2, page 66 (1994); Reference can be made to the report of Tatemoto, 49, 765 (1992).

  In the TEMPO (2,2,6,6-tetramethylpiperidinyl-1-oxy) method, a stable nitroxy free radical (= N—O.) Is generally used as a radical capping agent. Such compounds are not particularly limited, but 2,2,6,6-substituted-1-piperidinyloxy radical and 2,2,5,5-substituted-1-pyrrolidinyloxy radical Nitroxy free radicals from cyclic hydroxyamines are preferred. As the substituent, an alkyl group having 4 or less carbon atoms such as a methyl group or an ethyl group is suitable.

  Specific examples of nitroxy free radical compounds include 2,2,6,6-tetramethyl-1-piperidinyloxy radical (TEMPO), 2,2,6,6-tetraethyl-1-piperidinyloxy radical, 2,2,6,6-tetramethyl-4-oxo-1-piperidinyloxy radical, 2,2,5,5-tetramethyl-1-pyrrolidinyloxy radical, 1,1,3,3- Examples thereof include tetramethyl-2-isoindolinyloxy radical and N, N-di-t-butylamineoxy radical. Moreover, stable free radicals, such as a galvinoxyl free radical, can also be used instead of a nitroxy free radical.

  These radical capping agents are used in combination with a thermal radical generator. It is considered that the reaction product of the radical capping agent and the thermal radical generator serves as a polymerization initiator to proceed the polymerization of the addition polymerizable monomer, and the combination ratio of both is not particularly limited, but radical capping A suitable amount of the thermal radical generator is 0.1 to 10 moles per mole of the agent.

  As the thermal radical generator, various compounds can be used, but peroxides and azo compounds capable of generating radicals under polymerization temperature conditions are preferred. Examples of the peroxide include, but are not limited to, diacyl peroxides such as benzoyl peroxide and lauroyl peroxide; dialkyl peroxides such as dicumyl peroxide and di-t-butyl peroxide; diisopropyl peroxydicarbonate, bis Peroxycarbonates such as (4-t-butylcyclohexyl) peroxydicarbonate; alkyl peresters such as t-butylperoxyoctate and t-butylperoxybenzoate. Benzoyl peroxide is particularly preferable. As the azo compound, 2,2'-azobisisobutyronitrile, 2,2'-azobis- (2,4-dimethylvaleronitrile), 2,2'-azobis- (4-methoxy-2,4- Dimethyl valeronitrile), dimethyl azobisisobutyrate and the like, and dimethyl azobisisobutyrate is particularly preferable.

Examples of the solvent used in the living radical polymerization include cycloalkanes such as cyclohexane and cycloheptane; saturated carboxylic acids such as ethyl acetate, n-butyl acetate, i-butyl acetate, methyl propionate, and propylene glycol monomethyl ether acetate. Esters; alkyl lactones such as γ-butyrolactone; airs such as tetrahydrofuran, dimethoxyethanes and diethoxyethanes; alkyl ketones such as 2-butanone, 2-heptanone and methyl isobutyl ketone; cycloalkyl ketones such as cyclohexanone Alcohols such as 2-propanol and propylene glycol monomethyl ether; aromatics such as toluene, xylene and chlorobenzene; dimethylformamide, dimethyl sulfoxide, dimethylacetamide , It may be mentioned aprotic polar solvent or without a solvent, such as N- methyl-2-pyrrolidone.
These solvents can be used alone or in admixture of two or more.
Moreover, the reaction temperature in the said superposition | polymerization is 40-150 degreeC normally, Preferably it is 50-130 degreeC, and reaction time is 1 to 96 hours normally, Preferably it is 1 to 72 hours.

There is no restriction | limiting in particular as a pigment, According to the objective, it can select suitably from well-known pigments, The following are illustrated.
Examples of yellow pigments include cadmium yellow, mineral fast yellow, nickel titanium yellow, navel yellow, naphthol yellow S, hansa yellow G, hansa yellow 10G, benzidine yellow GR, quinoline yellow lake, permanent yellow NCG, and tartrazine lake. .
Examples of the orange pigment include molybdenum orange, permanent orange GTR, pyrazolone orange, vulcan orange, indanthrene brilliant orange RK, benzidine orange G, and indanthrene brilliant orange GK.
Examples of red pigments include Bengala, Cadmium Red, Permanent Red 4R, Resol Red, Pyrazolone Red, Watching Red Calcium Salt, Lake Red D, Brilliant Carmine 6B, Eosin Lake, Rhodamine Lake B, Alizarin Lake, Brilliant Carmine 3B.

Examples of purple pigments include fast violet B and methyl violet lake.
Examples of blue pigments include cobalt blue, alkali blue, Victoria blue lake, phthalocyanine blue, metal-free phthalocyanine blue, phthalocyanine blue partially chlorinated, first sky blue, and indanthrene blue BC.
Examples of green pigments include chrome green, chromium oxide, pigment green B, and malachite green lake.
Examples of black pigments include azine dyes such as carbon black, oil furnace black, channel black, lamp black, acetylene black, and aniline black, metal salt azo dyes, metal oxides, and composite metal oxides.
These can use 1 type (s) or 2 or more types.

  In particular, Pigment Yellow PY93, PY128, PY155, PY180, PY74, Pigment Blue PB15: 3, Pigment Red PR122, PR269, PR184, PR57: 1, PR238, PR146, PR185, Pigment Blue PB15: 3, Carbon Black, etc. are suitable. is there.

  The pigment may be used as a master batch combined with a resin. The resin is not particularly limited and may be appropriately selected from known ones according to the purpose. For example, styrene or a substituted polymer thereof, a styrene copolymer, polymethyl methacrylate, polybutyl methacrylate , Polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, polyester, epoxy resin, epoxy polyol resin, polyurethane, polyamide, polyvinyl butyral, polyacrylic acid resin, rosin, modified rosin, terpene resin, aliphatic hydrocarbon resin, alicyclic ring Aromatic hydrocarbon resin, aromatic petroleum resin, chlorinated paraffin, paraffin wax, and the like. These may be used individually by 1 type and may use 2 or more types together.

  Examples of the polymer of styrene or a substituted product thereof include polyester resin, polystyrene, poly p-chlorostyrene, polyvinyl toluene, and the like. Examples of the styrene copolymer include a styrene-p-chlorostyrene copolymer, a styrene-propylene copolymer, a styrene-vinyltoluene copolymer, a styrene-vinylnaphthalene copolymer, and a styrene-methyl acrylate copolymer. Polymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene- Butyl methacrylate copolymer, styrene-α-chloromethyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene An acrylonitrile-indene copolymer, Styrene - maleic acid copolymer, styrene - maleic acid ester copolymer, and the like.

  The masterbatch can be produced by mixing or kneading the masterbatch resin and the pigment with high shearing force. At this time, it is preferable to add an organic solvent in order to enhance the interaction between the pigment and the resin. The so-called flushing method is also preferable in that the wet cake of the pigment can be used as it is, and there is no need to dry it. This flushing method is a method in which an aqueous paste containing pigment water is mixed or kneaded together with a resin and an organic solvent, and the pigment is transferred to the resin side to remove moisture and organic solvent components. For the mixing or kneading, for example, a high shear dispersion device such as a three-roll mill is preferably used.

  The content of the pigment in the colored polymer particles is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 0.1 to 20% by mass, more preferably 1 to 15% by mass, and particularly 3 -10 mass% is preferable. When the content is less than 0.1% by weight, when used as a toner, a reduction in the coloring power of the toner is observed. When the content exceeds 20% by weight, poor dispersion of the pigment in the toner occurs, and the coloring power is reduced. This may lead to a decrease in the electrical characteristics of the toner.

Method for Producing Pigment Dispersion The pigment dispersion of the present invention comprises a mixture of at least the radical polymerizable monomer and the pigment in the presence of media such as glass beads, zirconia beads, alumina beads, iron balls, side grinders, paint shoes. After the pigment is pulverized and mixed or dissolved uniformly in a car, ball milling device, sand mill device, etc., the radical polymerizable monomer composition from which the media has been removed is further filled with supercritical fluid (or subcritical fluid). Pigments used in the present invention containing pigments, radical polymerizable monomers, and supercritical fluids (or subcritical fluids) by introducing into a high pressure cell and dispersing and mixing with sufficient shearing force using a stirrer A dispersion is obtained.
Regarding the method of mixing and dispersing with a supercritical fluid (or subcritical fluid), in addition, a method of introducing a supercritical fluid (or subcritical fluid) into a radical polymerizable monomer composition, a radical polymerizable monomer Examples of the method include introducing a liquid into the composition and heating to bring the liquid into a supercritical state. Any method can be used as long as it is a method used for the purpose of the present invention.
Further, a pigment may be dispersed in a supercritical fluid (or subcritical fluid), and a radical polymerizable monomer may be added thereto.

  In the composition of the pigment dispersion, the pigment is 0.1 to 50 parts by weight, preferably 0.5 to 30 parts by weight, more preferably 1 to 20 parts by weight with respect to 100 parts by weight of the radical polymerizable monomer. It is. If the composition is less than 0.1 part by mass, sufficient coloring power cannot be obtained, and if it exceeds 50 parts by mass, it is not preferable in terms of aggregation, sedimentation, or thickening of the pigment.

In the present invention, a pigment dispersant may be used in combination, and known ones can be used.
Examples of pigment dispersants include basic polymer copolymer dispersants, modified polyurethane dispersants, acidic polymer copolymer dispersants, polyester dispersants, acrylic acid, methacrylic acid and polymers of these esters. And colorant derivatives. Specific examples of the modified polyurethane-based dispersants include “Ajisper PB711”, “Azisper PB821”, and “Azisper PB822” (manufactured by Ajinomoto Fine Techno Co., Ltd.) as the basic polymer copolymer dispersant, and “EFKA- 4060 "," EFKA-4080 "," EFKA-7462 "," EFKA-4015 "," EFKA-4046 "," EFKA-4047 "," EFKA-4055 "," EFKA-4050 "(manufactured by EFKA CHEMICALS) Examples of the colorant derivative include Solsperse 22000 (manufactured by Avicia). Of course, the pigment dispersant is not limited to these, and other dispersants can also be used.
Moreover, although the addition amount of a pigment dispersant changes with surface areas of a pigment, it is good to add 1-30% of mass ratio with respect to a pigment.

In the present invention, 0 to 20 parts by weight, preferably 0 to 15 parts by weight, more preferably 0 to 10 parts by weight of a release agent is blended in the pigment dispersion with respect to 100 parts by weight of the radical polymerizable monomer. May be. Examples of the release agent include those shown below.
As a mold release agent, it can select suitably from well-known things according to the objective, For example, waxes, silicone oils, etc. are mentioned suitably.
Examples of the waxes include low molecular weight polyolefin waxes, synthetic hydrocarbon waxes, silicone waxes, natural waxes, petroleum waxes, higher fatty acids and metal salts thereof, higher fatty acid amides, and various modified waxes thereof. Can be mentioned. These may be used individually by 1 type and may use 2 or more types together.

Examples of the low molecular weight polyolefin wax include low molecular weight polyethylene wax and low molecular weight polypropylene wax.
Examples of the synthetic hydrocarbon wax include Fischer-Tropsch wax.
Examples of the natural waxes include beeswax, carnauba wax, candelilla wax, rice wax, and montan wax.
Examples of the petroleum wax include paraffin wax and microcrystalline wax. Examples of the higher fatty acid include stearic acid, palmitic acid, myristic acid, and the like.

  Silicone oils include dimethyl silicone oil, methyl phenyl silicone oil, methyl hydrogen silicone oil, polyether modified silicone oil, epoxy modified silicone oil, amino modified silicone oil, carboxyl modified silicone oil, mercapto modified silicone oil, carbinol modified. Silicone oil, methacrylic modified silicone oil, alkyl modified silicone oil, phenol modified silicone oil, fatty acid ester modified silicone oil, vinyl modified silicone oil, alkoxy modified silicone oil, heterogeneous functional group modified silicone oil, etc. One or more can be appropriately selected.

There is no restriction | limiting in particular as melting | fusing point of the said mold release agent (waxes), Although it can select suitably according to the objective, 40-160 degreeC is preferable, 50-120 degreeC is more preferable, 60-90 degreeC Is particularly preferred.
When the melting point is less than 40 ° C., the wax may adversely affect the heat-resistant storage stability. When the melting point exceeds 160 ° C., it may easily cause a cold offset when fixing at a low temperature. Paper wrapping may occur.

There is no restriction | limiting in particular as content in the said toner of the said mold release agent, Although it can select suitably according to the objective, 0-40 mass parts is preferable and 3-30 mass parts is more preferable.
When the content exceeds 40 parts by mass, the low-temperature fixability may be hindered or the image quality may be deteriorated (the glossiness is too high).

  By containing a release agent in the pigment dispersion, colored polymer particles containing the release agent can be obtained. In the dispersion polymerization in a supercritical fluid, the mechanism by which the release agent is included is not clear at present, but the following two mechanisms are conceivable. One is that the release agent dissolves due to heat and plastic effect in the supercritical fluid, and is taken in along with the dispersion polymerization. The other is considered that the release agent dissolved in some supercritical fluids is taken (injected) into the polymer particles according to the distribution coefficient. From the TEM photograph of the obtained colored polymer particles, it can be confirmed that the release agent is included because lamella can be observed inside the particles.

  The release agent may be mixed with a pigment or a radical polymerizable monomer and dispersed in the radical polymerizable monomer composition. However, in order to finely disperse the release agent, It is preferable to prepare a release agent dispersion prepared from the mold agent and the radical polymerizable monomer, and to mix and disperse the pigment and the radical polymerizable monomer using this.

The inorganic fine particles are not particularly limited and can be appropriately selected from known ones according to the purpose. For example, silica, alumina, titanium oxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate , Zinc oxide, tin oxide, silica sand, clay, mica, wollastonite, diatomaceous earth, chromium oxide, cerium oxide, pengala, antimony trioxide, magnesium oxide, zirconium oxide, barium sulfate, barium carbonate, calcium carbonate, silicon carbide , Silicon nitride, and the like. These may be used individually by 1 type and may use 2 or more types together.
The primary particle diameter of the inorganic fine particles is preferably 5 nm to 2 μm, and more preferably 5 nm to 500 nm. The specific surface area of the inorganic fine particles by BET method is preferably 20 to 500 m ² / g.
The content of the inorganic fine particles in the toner is preferably 0.01 to 5.0% by mass, and more preferably 0.01 to 2.0% by mass.

  The charge control agent can be appropriately selected from known ones according to the purpose. However, since a color tone may change when a colored material is used, a colorless or nearly white material is preferable. Dye, triphenylmethane dye, chromium-containing metal complex dye, molybdate chelate pigment, rhodamine dye, alkoxy amine, quaternary ammonium salt (including fluorine-modified quaternary ammonium salt), alkylamide, phosphorus alone or its Examples thereof include a compound, a simple substance of tungsten or a compound thereof, a fluorine-based activator, a metal salt of salicylic acid, and a metal salt of a salicylic acid derivative. There is no restriction | limiting in particular as said metal, According to the objective, it can select suitably, For example, aluminum, zinc, titanium, strontium, boron, silicon, nickel, iron, chromium, zirconium etc. are mentioned.

The charge control agent may be a commercially available product. Examples of the commercially available product include quaternary ammonium salt Bontron P-51, oxynaphthoic acid metal complex E-82, and salicylic acid metal complex. E-84, phenolic condensate E-89 (above, manufactured by Orient Chemical Co., Ltd.), quaternary ammonium salt molybdenum complex TP-302, TP-415 (above, manufactured by Hodogaya Chemical Co., Ltd.), No. Quaternary ammonium salt copy charge PSY VP2038, triphenylmethane derivative copy blue PR, quaternary ammonium salt copy charge NEG VP2036, copy charge NX VP434 (manufactured by Hoechst), LRA-901, boron complex LR-147 (Nippon Carlit), quinacridone, azo pigment, other sulfonic acid groups, cal Hexyl group, polymer compounds having a functional group such as quaternary ammonium salts, and the like.
The charge control agent may be melted and kneaded with the master batch and then dissolved or dispersed.

  The content of the charge control agent in the toner varies depending on the type of the binder resin, the presence or absence of the additive, and the like, and cannot be defined generally. 1-10 mass parts is preferable and 1-5 mass parts is more preferable. When the content is less than 0.1 parts by mass, the charging characteristics of the toner may be deteriorated. When the content exceeds 10 parts by mass, the chargeability of the toner becomes too large, and the effect of the main charge control agent is increased. , And the electrostatic attraction force with the developing roller increases, which may lead to a decrease in developer fluidity and a decrease in image density.

  The fluidity improver means a material that can be surface treated to increase hydrophobicity and prevent deterioration of flow characteristics and charging characteristics even under high humidity. For example, silane coupling agents, silylating agents And silane coupling agents having an alkyl fluoride group, organic titanate coupling agents, aluminum coupling agents, silicone oils, modified silicone oils, and the like.

  The cleaning property improver is added to the toner in order to remove the developer after transfer remaining on the photoreceptor or the primary transfer medium, for example, a fatty acid metal salt such as zinc stearate, calcium stearate, stearic acid, Examples include polymer fine particles produced by soap-free emulsion polymerization such as polymethyl methacrylate fine particles and polystyrene fine particles. The polymer fine particles preferably have a relatively narrow particle size distribution, and those having a volume average particle size of 0.01 to 1 μm are suitable.

  The shape, size, etc. of the toner is not particularly limited and can be appropriately selected according to the purpose. However, the following thermal characteristics, image density, average circularity, volume average particle diameter are as follows. It is preferable to have a ratio of volume average particle diameter to number average particle diameter (volume average particle diameter / number average particle diameter).

The thermal characteristics are also called flow tester characteristics, and are evaluated as, for example, softening temperature (Ts), outflow start temperature (Tfb), 1/2 method softening point (T1 / 2), and the like.
These thermal characteristics can be measured by an appropriately selected method. For example, the thermal characteristics can be obtained from a flow curve measured using an elevated flow tester CFT500 type (manufactured by Shimadzu Corporation). There is no restriction | limiting in particular as said softening temperature (Ts), According to the objective, it can select suitably, For example, 50 degreeC or more is preferable and 80-120 degreeC is more preferable. When the softening temperature (Ts) is less than 50 ° C., at least one of heat resistant storage stability and low temperature storage stability may deteriorate.
There is no restriction | limiting in particular as said outflow start temperature (Tfb), According to the objective, it can select suitably, For example, 60 degreeC or more is preferable and 70-150 degreeC is more preferable. If the outflow start temperature (Tfb) is less than 60 ° C., at least one of heat resistant storage stability and low temperature storage stability may deteriorate.
The 1/2 method softening point (T1 / 2) is not particularly limited and may be appropriately selected depending on the intended purpose. For example, 60 ° C. or higher is preferable, and 80 to 170 ° C. is more preferable. If the 1/2 method softening point (T1 / 2) is less than 60 ° C., at least one of heat resistant storage stability and low temperature storage stability may be deteriorated.

The image density is preferably 1.90 or more, more preferably 2.00 or more, and 2.10 or more, as measured by a spectrometer (X-Light, 938 Spectrodensitometer). Particularly preferred.
If the image density is less than 1.90, the image density may be low and high image quality may not be obtained. The image density, for example, imagio Neo 450 using (KK manufactured by Ricoh), a copy sheet; deposition amount of the developer (TYPE 6000 <70 W> Co. manufactured by Ricoh) is 1.00 ± 0.05mg / cm ² A solid image is formed at a surface temperature of the fixing roller of 160 ± 2 ° C., and the image density at any six locations in the obtained solid image is measured using a spectrometer (938 Spectrodensitometer manufactured by X-Light). It can be measured by measuring and calculating the average value.
Further, as the image density at a low adhesion amount, for example, after outputting a solid image at an adhesion amount of 0.3 ± 0.1 mg / cm ² , which is a low adhesion amount on plain paper transfer paper (Ricoh Co., Ltd., type 6200), The image density can be measured by measuring the image density at any six locations with X-Rite (manufactured by X-Rite) and calculating the average value. The image density at this time is preferably 1.3 or more, more preferably 1.35 or more, and further preferably 1.4 or more.

The average circularity is a value obtained by dividing the circumference of an equivalent circle having the same projected area as the shape of the toner by the circumference of the actual particles, and may be, for example, 0.850 to 1.000. However, 0.900 to 0.980 is preferable, and 0.950 to 0.975 is more preferable. The particles having a circularity of less than 0.94 are preferably 15% or less.
If the average circularity is less than 0.900, a satisfactory transferability and a high-quality image free from dust may not be obtained. If it exceeds 0.980, an image employing blade cleaning or the like is used. In the forming system, a defective cleaning occurs on the photosensitive member and the transfer belt, and in the case of image formation with a high image area ratio such as a photographic image, an image that has not been transferred due to a defective paper feed or the like is formed. The formed toner may become a transfer residual toner on the photoconductor, resulting in background smearing of the image, or it may contaminate the charging roller etc. that charges the photoconductor in contact with the original charging ability. May not be able to demonstrate.
The average circularity is measured by, for example, an optical detection band method in which a suspension containing toner is passed through an imaging unit detection band on a flat plate, and a particle image is optically detected and analyzed by a CCD camera. For example, it can be measured using a flow type particle image analyzer FPIA-2100 (manufactured by Toa Medical Electronics Co., Ltd.).

The volume average particle diameter of the toner is not particularly limited and may be appropriately selected depending on the intended purpose. For example, it is preferably 3 to 8 μm.
When the volume average particle size is less than 3 μm, in the case of a two-component developer, the toner may be fused to the surface of the carrier during a long period of stirring in the developing device, and the charging ability of the carrier may be reduced. In component developers, toner filming to the developing roller and toner fusion to the blade or other member are likely to occur because the toner is thinned. When the thickness exceeds 8 μm, the resolution is high. It becomes difficult to obtain a high-quality image, and when the balance of the toner in the developer is performed, the fluctuation of the toner particle size may increase.

  The ratio of the volume average particle diameter to the number average particle diameter (volume average particle diameter / number average particle diameter) in the toner is preferably 1.00 to 1.20, more preferably 1.00 to 1.15. Furthermore, 1.00 to 1.10 is more preferable for obtaining a high-definition image. When the ratio of the volume average particle diameter to the number average particle diameter (volume average particle diameter / number average particle diameter) exceeds 1.20, the two-component developer has a carrier surface in a long period of stirring in the developing device. In the case of a one-component developer, the toner filming on the developing roller or the toner is thinned so that the toner is melted onto a member such as a blade. In some cases, it is difficult to obtain a high-resolution and high-quality image, and the toner particle size fluctuates greatly when the balance of the toner in the developer is performed. There is.

  The volume average particle diameter and the ratio of the volume average particle diameter to the number average particle diameter (volume average particle diameter / number average particle diameter) are, for example, a particle size measuring instrument “Coulter Counter TAII” manufactured by Coulter Electronics Co., Ltd. Or “Coulter Multisizer II”.

(Developer)
The developer of the present invention contains at least the toner of the present invention and other components appropriately selected such as a carrier. The developer may be a one-component developer or a two-component developer. However, when it is used for a high-speed printer or the like corresponding to the recent improvement in information processing speed, the life is improved. In view of the above, the two-component developer is preferable.
In the case of the one-component developer using the toner of the present invention, even if the balance of the toner is performed, there is little fluctuation in the particle diameter of the toner, and the filming of the toner on the developing roller or the toner is made thin. Therefore, the toner is not fused to a member such as a blade, and good and stable developability and image can be obtained even when the developing device is used (stirred) for a long time. In addition, in the case of the two-component developer using the toner of the present invention, even if the toner balance for a long time is performed, the fluctuation of the toner diameter in the developer is small, and it is good even for long-term stirring in the developing device. And stable developability can be obtained.

-Career-
There is no restriction | limiting in particular as said carrier, Although it can select suitably according to the objective, What has a core material and the resin layer which coat | covers this core material is preferable.

  The core material is not particularly limited and may be appropriately selected from known materials. For example, 50 to 90 emu / g manganese-strontium (Mn—Sr) -based material, manganese-magnesium (Mn -Mg) -based materials and the like are preferable, and high magnetization materials such as iron powder (100 emu / g or more) and magnetite (75 to 120 emu / g) are preferable in terms of securing image density. In addition, a weakly magnetized material such as a copper-zinc (Cu—Zn) -based (30 to 80 emu / g) is advantageous in that it can weaken the contact with the photoconductor in which the toner is in a spiked state and is advantageous in improving the image quality. Is preferred. These may be used individually by 1 type and may use 2 or more types together.

The particle diameter of the core material is preferably a volume average particle diameter of 10 to 150 μm, and more preferably 40 to 100 μm.
If the average particle size (volume average particle size (D50)) is less than 10 μm, the distribution of carrier particles may increase the number of fine powders, lowering the magnetization per particle and causing carrier scattering. If the thickness exceeds 150 μm, the specific surface area may decrease and toner scattering may occur. In the case of a full color having a large solid portion, the reproduction of the solid portion may be deteriorated.

  The material of the resin layer is not particularly limited and may be appropriately selected from known resins according to the purpose. For example, amino resins, polyvinyl resins, polystyrene resins, halogenated olefin resins Polyester resin, polycarbonate resin, polyethylene resin, polyvinyl fluoride resin, polyvinylidene fluoride resin, polytrifluoroethylene resin, polyhexafluoropropylene resin, copolymer of vinylidene fluoride and acrylic monomer, fluoride Examples thereof include a copolymer of vinylidene and vinyl fluoride, a fluoroterpolymer such as a terpolymer of tetrafluoroethylene, vinylidene fluoride, and a non-fluorinated monomer, and a silicone resin. These may be used individually by 1 type and may use 2 or more types together.

  Examples of the amino resins include urea-formaldehyde resins, melamine resins, benzoguanamine resins, urea resins, polyamide resins, and epoxy resins. Examples of the polyvinyl resins include acrylic resins, polymethyl methacrylate resins, Examples include polyacrylonitrile resin, polyvinyl acetate resin, polyvinyl alcohol resin, polyvinyl butyral resin, and the like. Examples of the polystyrene resin include polystyrene resin and styrene acrylic copolymer resin. Examples of the halogenated olefin resin include polyvinyl chloride. Examples of the polyester resin include polyethylene terephthalate resin and polybutylene terephthalate resin.

  The resin layer may contain conductive powder or the like as necessary. Examples of the conductive powder include metal powder, carbon black, titanium oxide, tin oxide, and zinc oxide. The average particle diameter of these conductive powders is preferably 1 μm or less. When the average particle diameter exceeds 1 μm, it may be difficult to control electric resistance.

For example, the resin layer is prepared by dissolving the silicone resin or the like in a solvent to prepare a coating solution, and then uniformly coating the coating solution on the surface of the core material by a known coating method, drying, and baking. Can be formed. Examples of the application method include an immersion method, a spray method, and a brush coating method.
There is no restriction | limiting in particular as said solvent, Although it can select suitably according to the objective, For example, toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, cersol butyl acetate, etc. are mentioned.
The baking is not particularly limited, and may be an external heating method or an internal heating method. For example, a stationary electric furnace, a fluid electric furnace, a rotary electric furnace, a burner furnace, etc. The method of using, the method of using a microwave, etc. are mentioned.

  The amount of the resin layer in the carrier is preferably 0.01 to 5.0% by mass. When the amount is less than 0.01% by mass, the uniform resin layer may not be formed on the surface of the core material. When the amount exceeds 5.0% by mass, the resin layer becomes thick. In some cases, granulation of carriers occurs, and uniform carrier particles may not be obtained.

  When the developer is the two-component developer, the content of the carrier in the two-component developer is not particularly limited and may be appropriately selected depending on the intended purpose. For example, 90 to 98% by mass Is preferable, and 93-97 mass% is more preferable.

Since the developer of the present invention contains the toner, it is excellent in charging performance and can stably form a high-quality image during image formation.
The developer of the present invention can be suitably used for image formation by various known electrophotographic methods such as a magnetic one-component development method, a non-magnetic one-component development method, and a two-component development method. It can be particularly suitably used for containers, process cartridges, image forming apparatuses and image forming methods.

(Toner container)
The toner-containing container of the present invention comprises the toner or the developer of the present invention contained in a container. There is no restriction | limiting in particular as said container, It can select suitably from well-known things, For example, what has a container main body and a cap containing a toner etc. are mentioned suitably.
The size, shape, structure, material and the like of the container body containing toner are not particularly limited and can be appropriately selected according to the purpose. For example, the shape is preferably cylindrical. A spiral irregularity is formed on the peripheral surface, and the toner as the contents can be transferred to the discharge port side by rotating, and part or all of the spiral part has a bellows function, etc. Is particularly preferred.
The material of the toner-containing container body is not particularly limited, and those having good dimensional accuracy are preferable. For example, a resin is preferably used. Among them, for example, polyester resin, polyethylene resin, polypropylene resin, polystyrene resin, Preferable examples include vinyl chloride resin, polyacrylic acid, polycarbonate resin, ABS resin, polyacetal resin, and the like. The toner-containing container of the present invention is easy to store and transport, has excellent handleability, and is preferably used for replenishing toner by being detachably attached to the process cartridge and image forming apparatus of the present invention described later. Can do.

(Process cartridge)
The process cartridge of the present invention develops an electrostatic latent image carrier carrying an electrostatic latent image and the electrostatic latent image carried on the electrostatic latent image carrier using a developer to form a visible image. And at least developing means for forming the film, and other means appropriately selected as necessary.
The developing means includes a developer container that contains the toner or developer of the present invention, and a developer carrier that carries and transports the toner or developer contained in the developer container. And a layer thickness regulating member for regulating the thickness of the toner layer to be carried.
The process cartridge of the present invention can be detachably provided in various electrophotographic apparatuses, and is preferably provided detachably in the electrophotographic apparatus of the present invention described later.
An example of the process cartridge of the present invention is shown in FIG. In FIG. 1, 101 denotes an image carrier, 102 denotes a charging unit, 104 denotes a developing unit, and 107 denotes a cleaning unit.

(Image forming method and image forming apparatus)
The image forming method of the present invention includes at least an electrostatic latent image forming step, a developing step, a transfer step, and a fixing step, and other steps appropriately selected as necessary, for example, a static elimination step, a cleaning step, Includes recycling and control processes.
The image forming apparatus of the present invention includes at least an electrostatic latent image carrier, an electrostatic latent image forming unit, a developing unit, a transfer unit, and a fixing unit, and further appropriately selected as necessary. It has other means, for example, static elimination means, cleaning means, recycling means, control means and the like.

The electrostatic latent image forming step is a step of forming an electrostatic latent image on the electrostatic latent image carrier.
There are no particular restrictions on the material, shape, structure, size, etc. of the electrostatic latent image carrier (sometimes referred to as “photoconductive insulator” or “photoconductor”), and among the known ones The shape is preferably a drum shape, and examples of the material include inorganic photoconductors such as amorphous silicon and selenium, and organic photoconductors such as polysilane and phthalopolymethine. It is done. Among these, amorphous silicon or the like is preferable in terms of long life.

  The formation of the electrostatic latent image can be performed, for example, by uniformly charging the surface of the electrostatic latent image carrier and then performing imagewise exposure, and is performed by the electrostatic latent image forming unit. be able to. The electrostatic latent image forming means includes, for example, at least a charger that uniformly charges the surface of the electrostatic latent image carrier and an exposure device that exposes the surface of the electrostatic latent image carrier imagewise. Prepare.

The charging can be performed, for example, by applying a voltage to the surface of the electrostatic latent image carrier using the charger.
The charger is not particularly limited and may be appropriately selected depending on the purpose. For example, a known contact charging device including a conductive or semiconductive roll, brush, film, rubber blade, etc. And non-contact chargers using corona discharge such as corotrons and corotrons.

The exposure can be performed, for example, by exposing the surface of the latent electrostatic image bearing member imagewise using the exposure device.
The exposure device is not particularly limited as long as it can expose the surface of the electrostatic latent image carrier charged by the charger so as to form an image to be formed, and is appropriately selected according to the purpose. For example, various exposure devices such as a copying optical system, a rod lens array system, a laser optical system, and a liquid crystal shutter optical system can be used.
In the present invention, a back light system in which imagewise exposure is performed from the back side of the electrostatic latent image carrier may be employed.

-Development process and development means-
The developing step is a step of developing the electrostatic latent image using the toner or the developer of the present invention to form a visible image.
The visible image can be formed, for example, by developing the electrostatic latent image using the toner or the developer of the present invention, and can be performed by the developing unit.
The developing unit is not particularly limited as long as it can be developed using, for example, the toner or the developer of the present invention, and can be appropriately selected from known ones. For example, the toner of the present invention Preferred examples include a developer containing at least a developer, and at least a developing device capable of contacting or non-contacting the toner or the developer with the electrostatic latent image. More preferred is a developing device.

  The developing unit may be a dry developing type, a wet developing type, a single color developing unit, or a multi-color developing unit. For example, a toner having a stirrer for charging the toner or the developer by frictional stirring and a rotatable magnet roller is preferable.

  In the developing device, for example, the toner and the carrier are mixed and agitated, and the toner is charged by friction at that time, and held on the surface of the rotating magnet roller in a raised state to form a magnetic brush. . Since the magnet roller is disposed in the vicinity of the electrostatic latent image carrier (photoconductor), a part of the toner constituting the magnetic brush formed on the surface of the magnet roller is electrically attracted. It moves to the surface of the electrostatic latent image carrier (photoconductor) by force. As a result, the electrostatic latent image is developed with the toner, and a visible image is formed with the toner on the surface of the electrostatic latent image carrier (photoconductor).

  The developer accommodated in the developing device is a developer containing the toner of the present invention, but the developer may be a one-component developer or a two-component developer. The toner contained in the developer is the toner of the present invention.

In addition, it is preferable to apply an alternating electric field during the development step.
FIG. 6 is a diagram for explaining means for applying an alternating electric field during the development process. In the developing device 600 shown in FIG. 6, during development, a vibration bias voltage in which an AC voltage is superimposed on a DC voltage is applied to the developing sleeve 601 as a developing bias by the power source 602. The background portion potential and the image portion potential are located between the maximum value and the minimum value of the vibration bias potential. As a result, an alternating electric field whose direction changes alternately is formed in the developing unit 603. In this alternating electric field, the developer toner and the carrier vibrate vigorously, and the toner flies off the photosensitive drum 604 by shaking off the electrostatic binding force to the developing sleeve 601 and the carrier. And adhere.
The difference (the peak-to-peak voltage) between the maximum value and the minimum value of the vibration bias voltage is preferably 0.5 to 5 KV, and the frequency is preferably 1 to 10 KHz. As the waveform of the vibration bias voltage, a rectangular wave, a sine wave, a triangular wave, or the like can be used. As described above, the DC voltage component of the vibration bias is a value between the background part potential and the image part potential, but the value closer to the background part potential than the image part potential is more likely to cover the background part potential region. This is preferable for preventing toner adhesion.

  When the vibration bias voltage waveform is a rectangular wave, the duty ratio is preferably 50% or less. Here, the duty ratio is a ratio of time during which the toner is directed to the photosensitive member during one period of the vibration bias. By doing so, the difference between the peak value at which the toner is directed to the photoreceptor and the time average value of the bias can be increased, so that the movement of the toner is further activated and the potential of the latent image surface is increased. It can adhere to the distribution and improve the roughness and resolution. In addition, since the difference between the peak value of the carrier having a charge opposite to that of the toner and the time average value of the bias toward the photosensitive member can be reduced, the movement of the carrier is reduced, and the background portion of the latent image is reduced. The probability of carriers adhering to the substrate can be greatly reduced.

-Transfer process and transfer means-
The transfer step is a step of transferring the visible image onto a recording medium. After the primary transfer of the visible image onto the intermediate transfer member using an intermediate transfer member, the visible image is transferred onto the recording medium. A primary transfer step of forming a composite transfer image by transferring a visible image onto an intermediate transfer body using two or more colors, preferably full color toner as the toner, and a composite transfer image; A mode including a secondary transfer step of transferring the transfer image onto the recording medium is more preferable.
The transfer can be performed, for example, by charging the electrostatic latent image carrier (photoconductor) with the transfer charger using the visible image, and can be performed by the transfer unit. The transfer means includes a primary transfer means for transferring a visible image onto an intermediate transfer member to form a composite transfer image, and a secondary transfer means for transferring the composite transfer image onto a recording medium. Embodiments are preferred.
The intermediate transfer member is not particularly limited and may be appropriately selected from known transfer members according to the purpose. For example, a transfer belt and the like are preferable.

The transfer means (the primary transfer means and the secondary transfer means) is a transfer for peeling and charging the visible image formed on the electrostatic latent image carrier (photoconductor) to the recording medium side. It is preferable to have at least a vessel. There may be one transfer means or two or more transfer means.
Examples of the transfer device include a corona transfer device using corona discharge, a transfer belt, a transfer roller, a pressure transfer roller, and an adhesive transfer device.
The recording medium is not particularly limited and can be appropriately selected from known recording media (recording paper).

The fixing step is a step of fixing the visible image transferred to the recording medium using a fixing device, and may be performed each time the toner of each color is transferred to the recording medium, or for the toner of each color. You may perform this simultaneously in the state which laminated | stacked this.
There is no restriction | limiting in particular as said fixing device, Although it can select suitably according to the objective, A well-known heating-pressing means is suitable. The heating and pressing means is preferably one that is heated and pressed by a roller-shaped or belt-shaped fixing member, a combination of a heating roller and a pressure roller, a combination of a heating roller, a pressure roller, and an endless belt, Etc.
The heating in the heating and pressing means is usually preferably 80 ° C to 200 ° C.
In the present invention, for example, a known optical fixing device may be used together with or in place of the fixing step and the fixing unit depending on the purpose.

In addition to this, in the present invention, a film having a heating element provided with a heating element, a film in contact with the heating element, and a pressure member in pressure contact with the heating element through the film is used. It is preferable to pass a recording paper on which an unfixed toner image is formed between the pressure member and the pressure member to heat and fix the toner image.
FIG. 7 is a diagram for explaining the heat fixing unit as described above. As shown in FIG. 7, the fixing device used for the means is a so-called surf fixing device 700 for fixing by rotating a fixing film. More specifically, the fixing film 701 is an endless belt-like heat-resistant film, and is held by a driving roller 702 that is a supporting rotating body of the film 701, a driven roller 703, and a heater support provided below the two rollers. The heating body 704 is fixedly supported and is suspended.

The driven roller 703 also serves as a tension roller for the fixing film 701. The fixing film 701 is rotationally driven in the clockwise direction by the rotational driving of the driving roller 702 in the clockwise direction in the drawing. The rotational driving speed is adjusted to a speed at which the speeds of the transfer material 706 and the fixing film 701 are equal in the fixing nip region L where the pressure roller 705 and the fixing film 701 are in contact with each other.
Here, the pressure roller 705 is a roller having a rubber elastic layer having good releasability, such as silicon rubber, and a total pressure of 4 to 10 kg against the fixing nip region L while rotating counterclockwise. It is pressed with pressure.

  The fixing film 701 is preferably one having excellent heat resistance, releasability, and durability, and a thin film having a total thickness of 100 μm or less, preferably 40 μm or less is used. For example, at least an image of a single layer film of a heat-resistant resin such as polyimide, polyetherimide, PES (polyether sulfide), PFA (tetrafluoroethylene bar fluoroalkyl vinyl ether copolymer resin), or a composite layer film, for example, a 20 μm thick film The contact surface is coated with a release coating layer of PTFE (tetrafluoroethylene resin), PFA or other fluororesin added with a conductive material to a thickness of 10 μm, or an elastic layer such as fluororubber or silicon rubber. It is a thing.

In FIG. 7, the heating body 704 includes a flat substrate 707 and a fixing heater 708, and the flat substrate 707 is made of a material having high thermal conductivity and high electrical resistivity such as alumina and is in contact with the fixing film 701. On the surface, a fixing heater 708 made of a resistance heating element is installed in the longitudinal direction. The fixing heater 708 is obtained by coating an electric resistance material such as Ag / Pd or Ta ₂ N in a linear or belt shape by screen printing or the like. In addition, electrodes (not shown) are formed at both ends of the fixing heater, and the resistance heating element generates heat when energized between the electrodes. Further, a fixing temperature sensor 709 constituted by a thermistor is provided on the surface of the substrate opposite to the surface provided with the fixing heater 708.
The substrate temperature information detected by the fixing temperature sensor 709 is sent to a control unit (not shown), and the amount of electric power supplied to the fixing heater is controlled by the control unit, so that the heating body 704 is controlled to a predetermined temperature.
Such a fixing device is efficient and can shorten the rise time.

The neutralization step is a step of performing neutralization by applying a neutralization bias to the electrostatic latent image carrier, and can be suitably performed by a neutralization unit.
The neutralization means is not particularly limited, and may be appropriately selected from known neutralizers as long as it can apply a neutralization bias to the electrostatic latent image carrier. Preferably mentioned.

The cleaning step is a step of removing the electrophotographic toner remaining on the electrostatic latent image carrier, and can be suitably performed by a cleaning unit.
The cleaning means is not particularly limited as long as it can remove the electrophotographic toner remaining on the electrostatic latent image carrier, and can be appropriately selected from known cleaners. Suitable examples include brush cleaners, electrostatic brush cleaners, magnetic roller cleaners, blade cleaners, brush cleaners, web cleaners, and the like.

The recycling step is a step of recycling the electrophotographic color toner removed in the cleaning step to the developing unit, and can be suitably performed by the recycling unit.
There is no restriction | limiting in particular as said recycling means, A well-known conveyance means etc. are mentioned.

The control means is a process for controlling the respective steps, and can be suitably performed by the control means.
The control means is not particularly limited as long as the movement of each means can be controlled, and can be appropriately selected according to the purpose. Examples thereof include devices such as a sequencer and a computer.

  One mode for carrying out the image forming method of the present invention by the image forming apparatus of the present invention will be described with reference to FIG. An image forming apparatus 100 shown in FIG. 2 includes a photosensitive drum 10 as the electrostatic latent image carrier (hereinafter referred to as “photosensitive member 10”), a charging roller 20 as the charging unit, and exposure as the exposure unit. The apparatus 30 includes a developing device 40 as the developing means, an intermediate transfer member 50, a cleaning device 60 as the cleaning means having a cleaning blade, and a static elimination lamp 70 as the static elimination means.

  The intermediate transfer member 50 is an endless belt, and is designed to be movable in the direction of an arrow by three rollers 51 that are arranged inside and stretched. Part of the three rollers 51 also functions as a transfer bias roller that can apply a predetermined transfer bias (primary transfer bias) to the intermediate transfer member 50. The intermediate transfer body 50 is provided with a cleaning device 90 having a cleaning blade in the vicinity thereof, and for transferring (secondary transfer) a developed image (toner image) to a transfer sheet 95 as a final transfer material. A transfer roller 80 serving as a transfer unit to which a transfer bias can be applied is disposed to face the transfer roller 80. Around the intermediate transfer member 50, a corona charger 58 for applying a charge to the toner image on the intermediate transfer member 50 is arranged between the photosensitive member 10 and the intermediate transfer member 50 in the rotation direction of the intermediate transfer member 50. It is disposed between the contact portion and the contact portion between the intermediate transfer member 50 and the transfer paper 95.

  The developing device 40 includes a developing belt 41 as the developer carrying member, and a black developing unit 45K, a yellow developing unit 45Y, a magenta developing unit 45M, and a cyan developing unit 45C provided around the developing belt 41. . The black developing unit 45K includes a developer accommodating portion 42K, a developer supplying roller 43K, and a developing roller 44K. The yellow developing unit 45Y includes a developer accommodating portion 42Y, a developer supplying roller 43Y, and a developing roller 44Y. The magenta developing unit 45M includes a developer accommodating portion 42M, a developer supplying roller 43M, and a developing roller 44M, and the cyan developing unit 45C includes a developer accommodating portion 42C and a developer supplying roller 43C. And a developing roller 44C. The developing belt 41 is an endless belt, is rotatably stretched around a plurality of belt rollers, and a part thereof is in contact with the photoconductor 10.

  In the image forming apparatus 100 shown in FIG. 2, for example, the charging roller 20 charges the photosensitive drum 10 uniformly. The exposure device 30 performs imagewise exposure on the photosensitive drum 10 to form an electrostatic latent image. The electrostatic latent image formed on the photosensitive drum 10 is developed by supplying toner from the developing device 40 to form a visible image (toner image). The visible image (toner image) is transferred (primary transfer) onto the intermediate transfer member 50 by the voltage applied from the roller 51, and further transferred (secondary transfer) onto the transfer paper 95. As a result, a transfer image is formed on the transfer paper 95. The residual toner on the photoconductor 10 is removed by the cleaning device 60, and the charge on the photoconductor 10 is temporarily removed by the charge eliminating lamp 70.

  Another mode for carrying out the image forming method of the present invention by the image forming apparatus of the present invention will be described with reference to FIG. The image forming apparatus 100 shown in FIG. 3 does not include the developing belt 41 in the image forming apparatus 100 shown in FIG. 2, and a black developing unit 45K, a yellow developing unit 45Y, a magenta developing unit 45M, and Except for the fact that the cyan developing unit 45C is arranged directly opposite, it has the same configuration as the image forming apparatus 100 shown in FIG. In FIG. 3, the same components as those in FIG. 2 are denoted by the same reference numerals.

Another mode for carrying out the image forming method of the present invention by the image forming apparatus of the present invention will be described with reference to FIG. The tandem image forming apparatus shown in FIG. 4 is a tandem type color image forming apparatus. The tandem image forming apparatus includes a copying apparatus main body 150, a paper feed table 200, a scanner 300, and an automatic document feeder (ADF) 400.
The copying apparatus main body 150 is provided with an endless belt-like intermediate transfer member 50 at the center. The intermediate transfer member 50 is stretched around the support rollers 14, 15 and 16, and can be rotated clockwise in FIG. 4. An intermediate transfer member cleaning device 17 for removing residual toner on the intermediate transfer member 50 is disposed in the vicinity of the support roller 15. The intermediate transfer member 50 stretched between the support roller 14 and the support roller 15 is a tandem type in which four image forming units 18 of yellow, cyan, magenta, and black are arranged to face each other along the conveyance direction. A developing device 120 is disposed. An exposure device 21 is disposed in the vicinity of the tandem developing device 120. A secondary transfer device 22 is disposed on the side of the intermediate transfer member 50 opposite to the side on which the tandem developing device 120 is disposed. In the secondary transfer device 22, a secondary transfer belt 24, which is an endless belt, is stretched around a pair of rollers 23, and the transfer paper conveyed on the secondary transfer belt 24 and the intermediate transfer body 50 are in contact with each other. Is possible. A fixing device 25 is disposed in the vicinity of the secondary transfer device 22. The fixing device 25 includes a fixing belt 26 that is an endless belt, and a pressure roller 27 that is pressed against the fixing belt 26.
In the tandem image forming apparatus, a sheet reversing device 28 for reversing the transfer paper for image formation on both sides of the transfer paper is disposed in the vicinity of the secondary transfer device 22 and the fixing device 25. .

  Next, formation of a full-color image (color copy) using the tandem developing device 120 will be described. That is, first, a document is set on the document table 130 of the automatic document feeder (ADF) 400, or the automatic document feeder 400 is opened and the document is set on the contact glass 32 of the scanner 300. 400 is closed.

  When a start switch (not shown) is pressed, when the document is set on the automatic document feeder 400, the document is transported and moved onto the contact glass 32, and then the document is set on the contact glass 32. Immediately after that, the scanner 300 is driven, and the first traveling body 33 and the second traveling body 34 travel. At this time, light from the light source is irradiated by the first traveling body 33 and reflected light from the document surface is reflected by the mirror in the second traveling body 34 and is received by the reading sensor 36 through the imaging lens 35 to be color. An original (color image) is read and used as black, yellow, magenta, and cyan image information.

  Each image information of black, yellow, magenta and cyan is stored in each image forming means 18 (black image forming means, yellow image forming means, magenta image forming means and cyan image forming means in the tandem developing device 120. ) And black, yellow, magenta and cyan toner images are formed in the respective image forming means. That is, each image forming means 18 (black image forming means, yellow image forming means, magenta image forming means, and cyan image forming means) in the tandem type developing device 120 is photosensitive as shown in FIG. On the basis of the body 10 (the black photoconductor 10K, the yellow photoconductor 10Y, the magenta photoconductor 10M, and the cyan photoconductor 10C), the charger 20 that uniformly charges the photoconductor, and each color image information. The photosensitive member is exposed to each color image-corresponding image (L in FIG. 5), and an electrostatic latent image corresponding to each color image is formed on the photosensitive member. A developing device 61 that develops using color toner (black toner, yellow toner, magenta toner, and cyan toner) to form a toner image of each color toner, and the toner image is transferred to the intermediate transfer member 5. The image forming apparatus includes a transfer charger 62 for transferring the image on the surface, a photoconductor cleaning device 63, and a static eliminator 64, and each monochrome image (black image, yellow image, magenta image) based on image information of each color. And cyan images) can be formed. The black image, the yellow image, the magenta image, and the cyan image formed in this way are formed on the black photoconductor 10K on the intermediate transfer member 50 that is rotated by the support rollers 14, 15, and 16, respectively. The black image, the yellow image formed on the yellow photoconductor 10Y, the magenta image formed on the magenta photoconductor 10M, and the cyan image formed on the cyan photoconductor 10C are sequentially transferred (primary transfer). Is done. Then, the black image, the yellow image, the magenta image, and the cyan image are superimposed on the intermediate transfer member 50 to form a composite color image (color transfer image).

On the other hand, in the paper feed table 200, one of the paper feed rollers 142 is selectively rotated to feed out a sheet (recording paper) from one of the paper feed cassettes 144 provided in multiple stages in the paper bank 143. Each sheet is separated and sent to the paper feed path 146, transported by the transport roller 147, guided to the paper feed path 148 in the copying machine main body 150, and abutted against the registration roller 49 and stopped. Alternatively, the sheet feed roller is rotated to feed out sheets (recording paper) on the manual feed tray 54, separated one by one by the separation roller 52, put into the manual feed path 53, and abutted against the registration roller 49 and stopped. The registration roller 49 is generally used while being grounded, but may be used in a state where a bias is applied to remove paper dust from the sheet.
Then, the registration roller 49 is rotated in synchronization with the synthesized color image (color transfer image) synthesized on the intermediate transfer member 50, and a sheet (recording paper) is interposed between the intermediate transfer member 50 and the secondary transfer device 22. The secondary color transfer device 22 transfers the composite color image (color transfer image) onto the sheet (recording paper), thereby transferring the color image onto the sheet (recording paper). Is formed. The residual toner on the intermediate transfer member 50 after image transfer is cleaned by the intermediate transfer member cleaning device 17.

  The sheet (recording paper) on which the color image has been transferred is conveyed by the secondary transfer device 22 and sent to the fixing device 25, where the combined color image (color) is generated by heat and pressure. (Transfer image) is fixed on the sheet (recording paper). Thereafter, the sheet (recording paper) is switched by the switching claw 55 and discharged by the discharge roller 56 and stacked on the discharge tray 57, or switched by the switching claw 55 and reversed by the sheet reversing device 28 and transferred again. After being guided to the position and recording an image on the back surface, the image is discharged by the discharge roller 56 and stacked on the discharge tray 57.

  In the image forming apparatus and the image forming method of the present invention, since the toner of the present invention having excellent charging performance and surface properties is used, high image quality can be obtained efficiently.

Examples of the present invention will be described below, but the present invention is not limited to these examples.
Synthesis Example 1 Synthesis of Surfactant 1 1000 parts by mass of 1H, 1H-perfluorooctyl acrylate (manufactured by AMAX Co.) and 10 parts by mass of AIBN (2,2′-azobisisobutyronitrile by Wako Pure Chemical Industries) Into the reaction cell (50% by volume of the pressure vessel cell), carbon dioxide is selected as a supercritical fluid, the carbon dioxide is supplied into the processing cell by a supply cylinder, and 30 MPa, 65 by a pressure pump and a temperature controller. The reaction was carried out for 24 hours while adjusting the temperature. Subsequently, the temperature was lowered to 0 ° C., and the pressure was lowered to normal pressure using a back pressure valve, to obtain surfactant 1.
The weight average molecular weight (Mw) by GPC measurement (gel permeation chromatography) was 98,000.

Synthesis Example 2 Synthesis of Surfactant 2 500 parts by mass of 1H, 1H-perfluorooctyl methacrylate (manufactured by AMAX Co.), 500 parts by mass of styrene monomer and AIBN (2,2′-azobisisobutyronitrile manufactured by Wako Pure Chemical Industries) 5 parts are put into a pressure-resistant reaction cell (40% by volume of the pressure-resistant vessel cell), carbon dioxide is selected as a supercritical fluid, the carbon dioxide is supplied into the processing cell by a supply cylinder, and a pressure pump and temperature control are performed. The reactor was adjusted to 20 MPa and 65 ° C. and reacted for 48 hours. Subsequently, the temperature was lowered to 0 ° C., and the pressure was lowered to normal pressure using a back pressure valve to obtain surfactant 2.
The weight average molecular weight (Mw) by GPC measurement (gel permeation chromatography) was 85000.

Synthesis Example 3 Synthesis of Surfactant 3 1000 parts by mass of 2- (perfluorodecyl) ethyl acrylate (manufactured by AMAX Co.) and V-65 (2,2′-azobis (2,4-dimethylvaleronitrile) manufactured by Wako Pure Chemical Industries, Ltd.) 1 part by mass is put into a pressure-resistant reaction cell (30% by volume of the pressure-resistant vessel cell), carbon dioxide is selected as a supercritical fluid, the carbon dioxide is supplied into the processing cell by a supply cylinder, The reaction was carried out for 24 hours while adjusting the pressure to 35 MPa and 50 ° C. Using a regulator, the temperature was lowered to 0 ° C., and the pressure was lowered to normal pressure using a back pressure valve to obtain surfactant 3.
The weight average molecular weight (Mw) by GPC measurement (gel permeation chromatography) was 152000.

Synthesis Example 4 Synthesis of Surfactant 4 (Example of Bulk Polymerization)
100 parts by mass of 2- (perfluorooctyl) ethyl acrylate and 0.2 parts by mass of AIBN (2,2′-azobisisobutyronitrile, manufactured by Wako Pure Chemical Industries, Ltd.) were placed in a freezing ampoule (made of glass) containing a stirrer. Then, while the ampule was deaerated with a vacuum pump, (1) the sample was frozen in a dewar bottle containing liquid nitrogen and then (2) returned to room temperature and thawed. The operations from (1) to (2) were repeated about 20 times to deaerate the frozen ampoule, and then the ampoule upper part was heated and melted with a burner and sealed. This was placed in an oil bath at 120 ° C. and reacted for 72 hours while stirring in the ampoule. After completion of the reaction, the reaction mixture was cooled to room temperature, the ampoule upper part was cut, 500 parts by mass of hexafluorobenzene was added, the reaction product was dissolved, and this was added dropwise to 10000 parts by mass of methanol for reprecipitation purification. Further, this purification operation was performed three times to obtain white surfactant 4 (yield 98%). The weight average molecular weight (Mw) by GPC was 2.5 million.

Synthesis Example 5 Synthesis of Surfactant 5 (Example of Living Radical Polymerization)
300 parts by mass of 2- (perfluorooctyl) ethyl acrylate, 18 parts by mass of 4-methoxy-2,2,6,6-tetramethylpiperidine 1-oxyl and AIBN (2,2′-azobisisobuty manufactured by Wako Pure Chemical Industries, Ltd.) (Nitrile) 10 parts by mass in a freezing ampoule (made of glass) containing a stir bar, and (1) freezing in a dewar bottle containing liquid nitrogen while degassing the inside of the ampoule with (2) ) Returned to room temperature and thawed. The operations from (1) to (2) were repeated about 20 times to deaerate the frozen ampoule, and then the ampoule upper part was heated and melted with a burner and sealed. After putting this in a 90 ° C. oil bath, the bath temperature was raised to 155 ° C. over 30 minutes, and the reaction was carried out for 96 hours while stirring the inside of the ampoule.
After completion of the reaction, the reaction mixture was cooled to room temperature, the ampoule upper part was cut, 500 parts by mass of hexafluorobenzene was added, the reaction product was dissolved, and this was added dropwise to 10000 parts by mass of methanol for reprecipitation purification. Further, this purification operation was performed three times to obtain white surfactant 5 (yield 97%). The weight average molecular weight (Mw) by GPC was 95,000.

Example 1
-Preparation of polymerizable monomer composition-
C. I. Pigment Yellow PY180 (manufactured by Clariant) 50 parts by mass, styrene (800 parts by mass), n-butyl acrylate (200 parts by mass), and a polymerizable monomer and ethylene glycol dimethacrylate (5 parts by mass) and surfactant 1 (50 parts by mass) and 50 parts by mass of silicone wax (manufactured by Toray Dow Corning Co., Ltd., trade name: AMS-C30) and 3 mmφYTZ zirconia beads (10000 parts by mass) are placed in a container, and then a paint shaker (manufactured by Seiwa Giken) for 4 hours. Then, uniform dispersion was performed to prepare a polymerizable monomer composition 1.
<Supercritical polymerization process>
The polymerizable monomer composition 1 (150 parts by mass) is filled in a pressure-resistant reaction cell (30% by volume of the pressure-resistant vessel cell), carbon dioxide is selected as a supercritical fluid, and the carbon dioxide is supplied by a supply cylinder. It supplied to the processing cell and adjusted to 30 MPa and 65 degreeC with the pressurization pump and the temperature adjuster. To this was added 1.5 parts by mass of AIBN (2,2′-azobisisobutyronitrile manufactured by Wako Pure Chemical Industries) as a polymerization initiator to obtain a pigment dispersion, and a polymerization reaction was carried out for 40 hours.
After completion of the reaction, the reaction mixture was cooled to 5 ° C. and then reduced to normal pressure using a back pressure valve to obtain colored polymer particles 1 (yield 98%). In the particle size distribution measurement by Coulter Multisizer II (100 μm aperture tube), the weight average particle size (D4) was 5.3 μm, the number average particle size (Dn) was 5.0 μm, and D4 / Dn = 1.06.

Example 2
-Preparation of polymerizable monomer composition-
C. I. Pigment Red PR269 (Dainippon Ink Chemical Co., Ltd.) 100 parts by mass, styrene (493 parts by mass), methyl acrylate (403 parts by mass), divinylbenzene (4 parts by mass), and surfactant 2 (10 parts by mass) And 3 mmφYTZ zirconia beads (10000 parts by mass) were placed in a container and uniformly dispersed for 4 hours with a paint shaker (Seiwa Giken Co., Ltd.) to prepare a polymerizable monomer composition 2.
<Supercritical polymerization process>
The polymerizable monomer composition 2 (100 parts by mass) is filled in a pressure-resistant reaction cell (20% by volume of the pressure-resistant vessel cell), carbon dioxide is selected as a supercritical fluid, and the carbon dioxide is supplied by a supply cylinder. It supplied to the processing cell and adjusted to 20 MPa and 85 degreeC with the pressurization pump and the temperature adjuster. To this, 1 part by mass of AIBN (2,2′-azobisisobutyronitrile manufactured by Wako Pure Chemical Industries, Ltd.) as a polymerization initiator was added to obtain a pigment dispersion, and a polymerization reaction was performed for 40 hours.
After completion of the reaction, after cooling to 5 ° C., using the back pressure valve, adjusting the outlet side flow rate of the back pressure valve to 5.0 L / min, flowing carbon dioxide for 30 minutes to remove residual monomers, By gradually returning to normal pressure, colored polymer particles 2 (yield 97%) were obtained. In the particle size distribution measurement by Coulter Multisizer II (100 μm aperture tube), the weight average particle size (D4) was 6.4 μm, the number average particle size (Dn) was 6.0 μm, and D4 / Dn = 1.07.

Example 3
-Preparation of polymerizable monomer composition-
Pigment Blue PB15: 3 (manufactured by Dainichi Seika Co., Ltd.), 50 parts by mass, a polymerizable monomer comprising styrene (800 parts by mass), n-butyl acrylate (200 parts by mass), and ethylene glycol dimethacrylate (5 parts by mass) Surfactant 3 (100 parts by mass), 30 parts by mass of pentaerythritol tetrastearate (stearic acid: purity of about 60%) and natural gas Fischer-Tropsch wax (D Shell MS, trade name: FT &# 8722, melting point) 92 ° C.) 20 parts by mass and 3 mmφYTZ zirconia beads (10000 parts by mass) were placed in a container, and uniformly dispersed for 4 hours in a batch type sand mill apparatus (manufactured by Campehapio) to prepare polymerizable monomer composition 3.
<Supercritical polymerization process>
The pressure-resistant reaction cell containing 25 parts by mass of the polymerizable monomer composition 3 (150 parts by mass) and V-65 (2,2′-azobis (2,4-dimethylvaleronitrile) manufactured by Wako Pure Chemical Industries) as a polymerization initiator. (30% by volume of the pressure vessel cell), carbon dioxide is selected as a supercritical fluid, and the carbon dioxide is supplied to the treatment cell by a supply cylinder to obtain a pigment dispersion, and a pressure pump and a temperature regulator At 15 MPa and 50 ° C., and the polymerization reaction was carried out for 40 hours.
After completion of the reaction, after cooling to 5 ° C., using the back pressure valve, the flow rate on the outlet side of the back pressure valve is adjusted to 5.0 L / min, and after carbon dioxide is flown for 30 minutes to remove residual monomer, By gradually returning to normal pressure, colored polymer particles 3 (yield 97%) were obtained. In the particle size distribution measurement by Coulter Multisizer II (100 μm aperture tube), the weight average particle size (D4) was 7.2 μm, the number average particle size (Dn) was 6.8 μm, and D4 / Dn = 1.06.

Example 4
-Preparation of polymerizable monomer composition-
30 parts by mass of carbon black (Printex35, manufactured by Dexa), a polymerizable monomer composed of styrene (900 parts by mass) and ethylene glycol dimethacrylate (5 parts by mass), surfactant 4 (50 parts by mass), and synthetic ester wax (Nippon Yushi Co., Ltd., trade name: WEP-5) Take 65 parts by mass in a container and use a bead mill (Ultra Visco Mill, manufactured by Imex Co., Ltd.). A polymerizable monomer composition 4 was prepared by filling 80% by volume of zirconia beads and dispersing under conditions of 3 passes.
<Supercritical polymerization process>
The polymerizable monomer composition 4 (100 parts by mass) and 1 part by mass of AIBN (2,2′-azobisisobutyronitrile manufactured by Wako Pure Chemical Industries) as a polymerization initiator were added to a pressure-resistant reaction cell (pressure vessel cell). 20% by volume), carbon dioxide is selected as a supercritical fluid, and the carbon dioxide is supplied to the treatment cell by a supply cylinder to obtain a pigment dispersion, which is 35 MPa and 50 ° C. with a pressure pump and a temperature adjuster. The polymerization reaction was carried out for 40 hours.
After completion of the reaction, after cooling to 5 ° C., using the back pressure valve, the flow rate on the outlet side of the back pressure valve is adjusted to 5.0 L / min, and after carbon dioxide is flown for 30 minutes to remove residual monomer, By gradually returning to normal pressure, colored polymer particles 4 (99% yield) were obtained. In the particle size distribution measurement by Coulter Multisizer II (100 μm aperture tube), the weight average particle size (D4) was 4.3 μm, the number average particle size (Dn) was 4.0 μm, and D4 / Dn = 1.08.

Example 5
-Preparation of polymerizable monomer composition-
48 parts by mass of carbon black (manufactured by Regal 400R Cabot), 12 parts by mass of Pigment Blue PB15: 3 (manufactured by Dainichi Seika), styrene (800 parts by mass), n-butyl acrylate (200 parts by mass) and ethylene glycol dimethacrylate ( 3 parts by weight of a polymerizable monomer, surfactant 5 (5 parts by weight) and carnauba wax (product name: CWT01, manufactured by Toyo Petrolite Co., Ltd.) using a paint shaker (Seiwa Giken Co., Ltd.) Uniform dispersion was performed for 4 hours to prepare a polymerizable monomer composition 5.
<Supercritical polymerization process>
The polymerizable monomer composition 2 (250 parts by mass) is filled in a pressure-resistant reaction cell (50% by volume of the pressure-resistant vessel cell), carbon dioxide is selected as a supercritical fluid, and the carbon dioxide is supplied by a supply cylinder. It supplied to the processing cell and adjusted to 30 MPa and 65 degreeC with the pressurization pump and the temperature adjuster. 2.5 parts by mass of AIBN (2,2′-azobisisobutyronitrile manufactured by Wako Pure Chemical Industries, Ltd.) as a polymerization initiator was added thereto to obtain a pigment dispersion, and a polymerization reaction was performed for 24 hours.
After completion of the reaction, after cooling to 5 ° C., using the back pressure valve, the flow rate on the outlet side of the back pressure valve is adjusted to 5.0 L / min, and after carbon dioxide is flown for 30 minutes to remove residual monomer, By gradually returning to normal pressure, colored polymer particles 5 (yield 97%) were obtained. In the particle size distribution measurement by Coulter Multisizer II (100 μm aperture tube), the weight average particle size (D4) was 6.2 μm, the number average particle size (Dn) was 5.8 μm, and D4 / Dn = 1.07.

Examples 6-15
Colored polymer particles 6 to 15 were obtained in the same manner as in Example 1 except that the pigment used in Example 1 was changed to the pigment shown in Table 1. The results are shown in Table 1.

Example 16
-Preparation of polymerizable monomer composition-
C. I. 50 parts by weight of Pigment Yellow PY180 (manufactured by Clariant), 10 parts by basic pigment dispersant Ajisper PB821 (amine value: 10, acid value: 18 mgKOH / g, manufactured by Ajinomoto Fine Techno Co.), styrene (800 parts by weight) and n- Polymerizable monomer composed of butyl acrylate (200 parts by mass) and ethylene glycol dimethacrylate (5 parts by mass), surfactant 1 (50 parts by mass) and silicone wax (trade name: AMS-C30, manufactured by Toray Dow Corning) ) 50 parts by mass and 3 mmφYTZ zirconia beads (10000 parts by mass) were placed in a container, and uniformly dispersed for 4 hours with a paint shaker (manufactured by Seiwa Giken Co., Ltd.) to prepare a polymerizable monomer composition 6.
<Supercritical polymerization process>
The polymerizable monomer composition 1 (150 parts by mass) is filled in a pressure-resistant reaction cell (30% by volume of the pressure-resistant vessel cell), carbon dioxide is selected as a supercritical fluid, and the carbon dioxide is supplied by a supply cylinder. It supplied to the processing cell and adjusted to 30 MPa and 65 degreeC with the pressurization pump and the temperature adjuster. To this was added 1.5 parts by mass of AIBN (2,2′-azobisisobutyronitrile manufactured by Wako Pure Chemical Industries) as a polymerization initiator to obtain a pigment dispersion, and a polymerization reaction was carried out for 40 hours.
After completion of the reaction, the reaction mixture was cooled to 5 ° C. and then reduced to normal pressure using a back pressure valve to obtain colored polymer particles 16 (yield 95%). In the particle size distribution measurement by Coulter Multisizer II (100 μm aperture tube), the weight average particle size (D4) was 5.8 μm, the number average particle size (Dn) was 5.7 μm, and D4 / Dn = 1.02.

Examples 17-18
Toners 17 to 18 were obtained in the same manner as in Example 16 except that the pigments and pigment dispersants shown in Table 1 were used. The results are shown in Table 1.

Example 19
-Preparation of polymerizable monomer composition-
C. I. 50 parts by weight of Pigment Yellow PY180 (manufactured by Clariant), 10 parts of Ajisper PB821 (amine value: 10, acid value: 18 mg KOH / g, manufactured by Ajinomoto Fine Techno Co., Ltd.), 2.5 parts of “Solsperse 22000” (manufactured by Abyssia), styrene (800 parts by mass), n-butyl acrylate (200 parts by mass), a polymerizable monomer comprising ethylene glycol dimethacrylate (5 parts by mass), surfactant 1 (50 parts by mass), and silicone wax (Toray Dow Corning) Product name: AMS-C30) 50 parts by mass and 3 mmφYTZ zirconia beads (10000 parts by mass) are placed in a container, and uniformly dispersed with a paint shaker (manufactured by Seiwa Giken Co., Ltd.) for 4 hours. 6 was prepared.
<Supercritical polymerization process>
The polymerizable monomer composition 1 (150 parts by mass) is filled in a pressure-resistant reaction cell (30% by volume of the pressure-resistant vessel cell), carbon dioxide is selected as a supercritical fluid, and the carbon dioxide is supplied by a supply cylinder. It supplied to the processing cell and adjusted to 30 MPa and 65 degreeC with the pressurization pump and the temperature adjuster. To this was added 1.5 parts by mass of AIBN (2,2′-azobisisobutyronitrile manufactured by Wako Pure Chemical Industries) as a polymerization initiator to obtain a pigment dispersion, and a polymerization reaction was carried out for 40 hours.
After the completion of the reaction, the reaction mixture was cooled to 5 ° C. and then reduced to normal pressure using a back pressure valve to obtain colored polymer particles 19 (yield 95%). In the particle size distribution measurement by Coulter Multisizer II (100 μm aperture tube), the weight average particle size (D4) was 5.5 μm, the number average particle size (Dn) was 5.4 μm, and D4 / Dn = 1.02.

Comparative Example 1
A sealable reaction vessel equipped with a stirring blade, a cooling condenser, and a nitrogen gas introduction tube was installed in a constant temperature water tank, and the reaction vessel was charged with the following composition.
Ethanol 70 parts by weight Distilled water 30 parts by weight Polyvinylpyrrolidone 4 parts by weight The stirring blade was rotated to completely dissolve polyvinylpyrrolidone.
Next, the polymerizable monomer composition 6 (40 parts by mass) prepared in Example 6 was charged into a reaction vessel, and 0.03 parts by mass of carbon tetrachloride and 0.6 parts by mass of benzoyl peroxide were added.
Subsequently, while rotating the stirring blade, nitrogen gas was blown into the container to completely expel oxygen, and then the temperature in the water tank was raised to 50 ± 0.1 ° C. to initiate polymerization. After 2 hours, the temperature was raised to 65 ± 0.1 ° C. in the water bath to increase the reaction rate.
After 40 hours from the start of the reaction, the mixture was cooled to room temperature to obtain a dispersion. As a result of partial sampling and measurement by gas chromatography using an internal standard method, the polymerization rate was 90%. This dispersion was washed with ethanol, centrifuged and settled, the supernatant was removed, and the operation of redispersing in ethanol was performed three times, followed by filtration to obtain comparative colored polymer particles 1 (yield 90%). In the particle size distribution measurement using a Coulter counter (100 μm aperture tube), the weight average particle size (D4) was 8.3 μm, the number average particle size was 6.7 μm, and D4 / Dn = 1.24.

Comparative Examples 2-3
Comparative colored polymer particles 2 to 3 were obtained in the same manner as in Comparative Example 1 except that the pigments and pigment dispersants shown in Table 1 were changed.

To 100 parts by mass of the colored polymer particles thus obtained, 0.7 part by mass of hydrophobic silica and 0.3 part by mass of hydrophobized titanium oxide are added, and a Henschel mixer is used at a peripheral speed of 8 m / s. Mix for 5 minutes. The powder after mixing was passed through a mesh having an opening of 100 μm, and coarse powder was removed to obtain a toner. Next, 5% by mass of the toner subjected to the external additive treatment and 95% by mass of a copper-zinc ferrite carrier having an average particle diameter of 40 μm coated with a silicone resin are rolled and stirred. Two-component developers 1 to 19 were prepared by uniformly mixing and charging using a mixer. (The colored polymer particles used in the developers 1 to 19 correspond to the colored polymer particles 1 to 19 in sequence.)
One component development in which 0.7 parts by mass of hydrophobic silica and 0.3 parts by mass of hydrophobized titanium oxide were added to 100 parts of colored polymer particles and mixed for 5 minutes with a Henschel mixer at a peripheral speed of 8 m / s. Agents 20-38 were also prepared. (The colored polymer particles used in the developers 20 to 38 sequentially correspond to the colored polymer particles 1 to 19, respectively.)

As for the comparative developer, 0.7 parts by weight of hydrophobic silica and 0.3 parts by weight of hydrophobic titanium oxide were added to 100 parts by weight of the comparative colored polymer particles, and the peripheral speed was 8 m / s using a Henschel mixer. A comparative toner was obtained by mixing for 5 minutes. Next, 5% by mass of the toner subjected to the external additive treatment and 95% by mass of a copper-zinc ferrite carrier having an average particle diameter of 40 μm coated with a silicone resin are rolled and stirred. Comparative developers 1 to 3 which are two-component developers were prepared by uniformly mixing and charging using a mixer. (The colored polymer particles used in the comparative developers 1 to 3 correspond to the comparative colored polymer particles 1 to 3, respectively.)
Furthermore, 0.7 parts by mass of hydrophobic silica and 0.3 parts by mass of hydrophobized titanium oxide were added to 100 parts by mass of the comparative colored polymer particles, and the mixture was mixed with a Henschel mixer at a peripheral speed of 8 m / s for 5 minutes. Comparative developers 4 to 6, which are component developers, were prepared. (The colored polymer particles used in the comparative developers 4 to 6 correspond to the comparative colored polymer particles 1 to 3, respectively.)

For the obtained developers 1 to 38 and comparative developers 1 to 6, an image forming apparatus (Ricoh Co., Ltd., IPSio Color 8100 is used for evaluation of the two-component developer, and for evaluation of the one-component developer, Ricoh Co., Ltd., imagio Neo C200 is used), and an image is output and evaluated as follows. The results are shown in Table 2.
<Image density>
After outputting a solid image at an adhesion amount of 0.3 ± 0.1 mg / cm ² , which is a low adhesion amount on plain paper transfer paper (type 6200, manufactured by Ricoh Co., Ltd.), the image density is set to X-Rite (X-Rite Corporation). The image density is 1.4 or more, ◯, 1.35 or more and less than 1.4 is ◯, 1.3 or more and less than 1.35 is Δ, and less than 1.3 is x.

<Cleanability>
The transfer residual toner on the photosensitive member that has passed the cleaning process after outputting 1,000 sheets of a 95% image area ratio chart is transferred to white paper with Scotch tape (manufactured by Sumitomo 3M Limited), and measured with a Macbeth reflection densitometer RD514 type. The evaluation was made according to the following criteria.
〔Evaluation criteria〕
A: The difference from the blank is less than 0.005.
○: The difference from the blank is 0.005 or more and less than 0.010.
(Triangle | delta): The difference with a blank is 0.010 or more and less than 0.02.
X: The difference from the blank is 0.02 or more.

<Transferability>
After the image area ratio 20% chart is transferred from the photoconductor to the paper, the transfer residual toner on the photoconductor immediately before cleaning is transferred to a white paper with a scotch tape (manufactured by Sumitomo 3M Co., Ltd.). Measured and evaluated according to the following criteria.
〔Evaluation criteria〕
A: The difference from the blank is less than 0.005.
○: The difference from the blank is 0.005 or more and less than 0.010.
(Triangle | delta): The difference with a blank is 0.010 or more and less than 0.02.
X: The difference from the blank is 0.02 or more.

<Toner scattering>
In an environment of a temperature of 40 ° C. and a humidity of 90% RH, an image forming apparatus (Ricoh Co., Ltd., IPSiO Color 8100) was remodeled to an oil-less fixing system and tuned to an evaluation machine. The toner contamination state in the copier after the% chart continuous 100,000 sheet output durability test was visually evaluated according to the following criteria.
〔Evaluation criteria〕
A: The toner is not observed at all and is in a good state.
○: Slight dirt is observed, and there is no problem.
Δ: Slightly dirty.
X: Very dirty and out of the allowable range.

<Charging stability>
Using each toner, a continuous 100,000 sheet output durability test was conducted using a character image pattern with an image area ratio of 12%, and the change in the charge amount at that time was evaluated. A small amount of developer was collected from the sleeve, the change in charge amount was determined by the blow-off method, and evaluated according to the following criteria.
〔Evaluation criteria〕
○: Change in charge amount is less than 5 μc / g.
Δ: Change in charge amount is 5 μc / g or more and 10 μc / g or less.
X: Change in charge amount exceeds 10 μc / g.

<Filming properties>
Filming on the developing roller after outputting 1000 sheets of band charts with image area ratios of 100%, 75%, and 50% and filming on the photoreceptor were observed and evaluated according to the following criteria.
〔Evaluation criteria〕
A: Filming does not occur at all.
○: The occurrence of filming can be confirmed slightly.
Δ: Filming occurs in streaks.
X: Filming has occurred on the entire surface.

From the results shown in Table 2, the developer 1 to 38 using the polymerization method toner obtained by this method has toner scattering, transferability, charging stability, filming property, and cleaning property as compared with the comparative developers 1 to 6. It was confirmed that a high image density can be obtained.
Also, in this toner production method, no waste liquid is generated, and a dry polymerization toner can be obtained simply by returning to normal pressure. Therefore, the conventional method is used in terms of low cost, low environmental load, energy saving, and resource saving. It has also been found that it is possible to provide an innovative toner production method that is not present.

The particle diameter, molecular weight of the colored polymer particles, and the molecular weight of the surfactant were measured as follows.
Particle size measurement Examples of a measurement device for the particle size distribution of toner particles by the Coulter counter method include Coulter counter TA-II and Coulter Multisizer II (both manufactured by Coulter Co.). The measurement method is described below.
First, 0.1 to 5 ml of a surfactant (preferably polyoxyethylene alkyl ether: trade name dry well) is added as a dispersant to 100 to 150 ml of an electrolytic aqueous solution. Here, the electrolytic solution is a solution prepared by preparing a 1% NaCl aqueous solution using first grade sodium chloride. For example, ISOTON-II (manufactured by Coulter) can be used. Here, 2 to 20 mg of a measurement sample is further added. The electrolytic solution in which the sample is suspended is subjected to a dispersion treatment with an ultrasonic disperser for about 1 to 3 minutes, and the measurement device is used to measure the volume and number of toner particles or toner using a 100 μm aperture as an aperture. Volume distribution and number distribution are calculated. From the obtained distribution, the weight average particle diameter (D4) and the number average particle diameter of the toner can be obtained.
As channels, 2.00 to less than 2.52 μm; 2.52 to less than 3.17 μm; 3.17 to less than 4.00 μm; 4.00 to less than 5.04 μm; 5.04 to less than 6.35 μm; 6 Less than 35 to 8.00 μm; less than 8.00 to less than 10.08 μm; less than 10.08 to less than 12.70 μm; less than 12.70 to less than 16.00 μm; less than 16.00 to less than 20.20 μm; Uses 13 channels of less than 40 μm; 25.40 to less than 32.00 μm; 32.00 to less than 40.30 μm, and targets particles having a particle size of 2.00 μm to less than 40.30 μm.

Molecular weight measurement by GPC (in the case of colored particles)
The number average molecular weight Mn was measured by GPC (gel permeation chromatography) under the following conditions.
・ Apparatus: GPC-150C (manufactured by Waters)
Column: KF801-807 (manufactured by Shodex)
・ Temperature: 40 ℃
・ Solvent: THF (tetrahydrofuran)
・ Flow rate: 1.0 ml / min ・ Sample: 0.1 ml injection of a sample with a concentration of 0.05 to 0.6% A molecular weight calibration curve created from a monodisperse polystyrene standard sample from the molecular weight distribution of the sample measured under the above conditions The number average molecular weight Mn and the weight average molecular weight Mw of the sample were calculated.

Molecular weight measurement by GPC (in case of surfactant)
・ Equipment: HLC-8220GPC manufactured by TOSOH
-Column: TSKgel GMHHR-M (inner diameter 4.6 mm x length 15 cm) x 3-Guard column: TSK guard column HHRH (S)
Solvent: HFIP (hexafluoroisopropanol) 5 mM sodium trifluoroacetate
Solution ・ Flow rate: 0.2 ml / min
・ Injection volume: 10 μl
Column temperature: 40 ° C
Sample concentration: 0.15 wt%
Detector: UV (254 nm), RI
The molecular weight calculation was optimized with a cubic curve using standard PMMA (polymethyl methacrylate), and the number average molecular weight Mn and the weight average molecular weight Mw were calculated.

FIG. 1 is a schematic configuration diagram showing an example of a process cartridge of the present invention. FIG. 2 is a schematic configuration diagram showing an example of the image forming apparatus of the present invention. FIG. 3 is a schematic configuration diagram showing another example of the image forming apparatus of the present invention. FIG. 4 is a schematic configuration diagram showing another example of the image forming apparatus of the present invention. FIG. 5 is a schematic configuration diagram showing another example of the image forming apparatus of the present invention. FIG. 6 is a schematic configuration diagram showing an example of the developing unit of the image forming apparatus of the present invention. FIG. 7 is a schematic configuration diagram illustrating an example of a fixing unit of the image forming apparatus of the present invention.

Explanation of symbols

(Figure 1)
DESCRIPTION OF SYMBOLS 101 Image carrier 102 Charging device 104 Developing device 107 Cleaning device (FIGS. 2 to 5)
10 Photoconductor (Photoconductor drum)
10K black photoconductor 10Y yellow photoconductor 10M magenta photoconductor 10C cyan photoconductor 14 support roller 15 support roller 16 support roller 17 intermediate transfer cleaning device 18 image forming means 20 charging roller (charger)
DESCRIPTION OF SYMBOLS 21 Exposure apparatus 22 Secondary transfer apparatus 23 Roller 24 Secondary transfer belt 25 Fixing apparatus 26 Fixing belt 27 Pressure roller 28 Sheet inversion apparatus 30 Exposure apparatus 32 Contact glass 33 1st traveling body 34 2nd traveling body 35 Imaging lens 36 Reading sensor 40 Developing device 41 Developing belt 42K Developer container 42Y Developer container 42M Developer container 42C Developer container 43K Developer supply roller 43Y Developer supply roller 43M Developer supply roller 43C Developer supply roller 44K Development Roller 44Y Developing roller 44M Developing roller 44C Developing roller 45K Black developing unit 45Y Yellow developing unit 45M Magenta developing unit 45C Cyan developing unit 49 Registration roller 50 Intermediate transfer member 51 Roller 52 Separating roller 53 Manual feeding Paper feeding path 54 manual feed tray 55 switching claw 56 discharge roller 57 discharge tray 58 corona charger 60 cleaning device 61 developing device 62 transfer charger 63 photoconductor cleaning device 64 static eliminator 70 static elimination lamp 80 transfer roller 90 cleaning device 95 transfer paper DESCRIPTION OF SYMBOLS 100 Image forming apparatus 120 Tandem type developing device 130 Document base 142 Paper feed roller 143 Paper bank 144 Paper feed cassette 145 Separating roller 146 Paper feed path 147 Conveyance roller 148 Paper feed path 150 Copying device main body 152 Corona charger 153 Constant current source 200 Paper feeding table 210 Image fixing device 220 Heating roller 230 Pressure roller 300 Scanner 400 Automatic document feeder (ADF)
(Fig. 6)
600 Developing Unit 601 Developing Sleeve 602 Power Supply 603 Developing Unit 604 Photosensitive Drum (FIG. 7)
700 Surf Fixing Device 701 Fixing Film 702 Driving Roller 703 Driven Roller 704 Heating Body 705 Pressing Roller 706 Transfer Material 707 Flat Substrate 708 Fixing Heater 709 Fixing Temperature Sensor

Claims (5)

A pigment dispersion containing a supercritical fluid or subcritical fluid that dissolves at least a radical polymerizable monomer but does not dissolve polymer particles obtained by polymerizing the radical polymerizable monomer, the radical polymerizable monomer, and a pigment A method for producing colored polymer particles, wherein the radical polymerizable monomer is polymerized by a dispersion polymerization method to obtain colored polymer particles insoluble in the supercritical fluid or subcritical fluid.   The method for producing colored polymer particles according to claim 1, wherein the supercritical fluid or subcritical fluid is supercritical carbon dioxide or subcritical carbon dioxide.   The colored pigment particles according to claim 1 or 2, wherein the pigment dispersion further contains a surfactant that functions as both a supercritical fluid or subcritical fluid and a radical polymerizable monomer. Method. The method for producing colored polymer particles according to any one of claims 1 to 3 , wherein the pigment dispersion further contains a release agent to obtain colored polymer particles containing the release agent. The method for producing colored polymer particles according to claim 3 or 4 , wherein the surfactant has a partial structural formula represented by the following general formula (1).

(In the formula, R ₁ represents a hydrogen atom or a methyl group, R ₂ represents a methylene group or an ethylene group, and R f represents a perfluoroalkyl group having 7 to 10 carbon atoms.)

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