JP2001117269A - Method of forming image - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of forming an image by which an image having excellent smoothness, transparency, color mixing property and color developing property can be formed when an image is to be formed on a transparent transfer body, excellent peeling property of a nonfixing sheet and hot offset resistance are obtained and an image with high picture quality and reliability is obtained. SOLUTION: In the method of forming an image by developing and fixing an electrostatic latent image with a developer, the transparent transfer body used has a resin layer on its surface, and a toner containing at least a binder resin and a coloring agent is used as the developer. The crosslink density Me of the toner obtained by temperature dispersion measurement in the dynamic viscoelasticity ranges 1.6×10-8 to 3.5×10-6/kmol. The gloss degree Gs of a fixed surface when the image is molten and fixed on the transparent transfer body is >=80%.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming an image by developing an electrostatic latent image by electrophotography using an electrostatic image developing toner.

[0002]

2. Description of the Related Art Methods of visualizing image information via an electrostatic image, such as electrophotography, are currently widely used in various fields. In the electrophotographic method, an electrostatic image is formed on a photoreceptor through a charging step, an exposure step, and the like, and is developed with a developer, transferred, and fixed to visualize the electrostatic image.

[0003] As the developer used here, a two-component developer containing a toner and a carrier and a one-component developer containing a magnetic toner or a non-magnetic toner are known. The toner is usually manufactured by a melt-kneading pulverization method. This kneading and pulverization method is to melt-knead a thermoplastic resin or the like together with a pigment, a charge controlling agent, a release agent such as wax, and the like, and after cooling, pulverize the melt-kneaded product and classify it to produce desired toner particles. It is. The toner produced by the melt-kneading pulverization method is used by adding inorganic fine particles or organic fine particles to the surface thereof for the purpose of improving fluidity, cleaning property and the like.

[0004] Toner particles produced by the melt-kneading and pulverizing method are usually irregular in shape and not uniform in surface composition. Since the shape and surface composition of the toner particles are delicately changed depending on the pulverizability and the pulverization conditions of the materials used, it is difficult to intentionally control these. In particular, toner particles manufactured by a melt-kneading pulverization method using a material having high pulverizability are subjected to mechanical forces such as various shearing forces inside the developing machine, and are further pulverized and pulverized, or the shape thereof is changed. Or As a result, in a two-component developer, the finely-divided toner particles adhere to the carrier surface, accelerating the deterioration of the charge of the developer, and in a one-component developer, the particle size distribution increases, and There is a problem that the toner particles are scattered or the developability is deteriorated due to a change in the shape of the toner, thereby deteriorating the image quality.

If the shape of the toner particles is irregular, sufficient fluidity cannot be ensured even when the fluidity aid is added, and the fine particles of the fluidity aid are depressed by the mechanical force during use. And buried in the inside thereof, and there is a problem that the fluidity decreases over time, and the developing property, transfer property, cleaning property and the like deteriorate. Further, if such a toner is collected by the cleaning process, returned to the developing device, and reused, there is a problem that the image quality is easily deteriorated. In order to prevent these problems, it is conceivable to further increase the amount of the flow aid. However, black spots are generated on the photoconductor and the flow aid particles are scattered.

[0006] On the other hand, a toner obtained by internally adding a release agent such as wax may be used in combination with a thermoplastic resin.
The release agent may be exposed on the surface of the toner particles. In particular, in the case of a toner formed by combining a resin which is imparted with elasticity by a high molecular weight component and is hardly pulverized, and a brittle wax such as polyethylene, polyethylene is often exposed on the surface. Such a toner is advantageous for the releasability at the time of fixing and cleaning of the untransferred toner from the photoreceptor, but the polyethylene on the surface of the toner particles is hardened by mechanical force such as shearing force in a developing machine. From the developer, easily migrate to the developing roll, the photoconductor, the carrier, etc., and contaminate them, and thus the reliability of the developer is reduced.

[0007] For example, a suspension polymerization method is proposed in JP-A-8-44111 and JP-A-8-286416. The suspension polymerization method is a method in which a polymerizable monomer is dispersed and suspended in an aqueous medium together with a coloring agent, a release agent, and the like, and the polymerizable monomer is polymerized to obtain toner particles. According to this suspension polymerization method, for example, toner particles having a multilayer structure in which wax as a release agent is coated with a binder resin can be obtained.

However, in this suspension polymerization method, it is necessary to adjust particles to an appropriate size in a suspension state. For that purpose, it is necessary to stir the dispersion liquid strongly and at high speed. Generally, it is extremely difficult to stir uniformly a liquid having a viscosity such as water at a high speed. Non-uniform mixing liberates the release agent and generates a large amount of toner having a significantly low or no release agent content, resulting in a large uneven distribution of the composition between toner particles, and the required fixing of the toner. There is a problem that various properties such as charging property and charging property cannot be sufficiently satisfied.

In recent years, an emulsion polymerization aggregation fusion method has been proposed as a method for producing a toner capable of intentionally controlling the shape and surface composition of particles. In this emulsion polymerization coagulation fusion method, a resin dispersion is prepared by emulsion polymerization, a colorant dispersion in which a colorant is dispersed in a solvent, and a dispersion in which a release agent is dispersed are prepared. This is a method in which agglomerated particles corresponding to the particle size of the toner are formed by mixing and then fused by heating to obtain toner particles. In this emulsion polymerization aggregation fusion method, the shape can be arbitrarily controlled by selecting the heating temperature conditions, and the charging property and durability can be improved.

[0010] In such an electrophotographic process, in order to maintain stable performance of the toner even under various mechanical stresses, the exposure of the release agent to the toner surface is suppressed or the fixing property is not impaired. While increasing the surface hardness,
It is necessary to improve the mechanical strength of the toner itself and to achieve both sufficient chargeability and fixability.

Particularly, with the progress of color images in recent years, there is a remarkable tendency to reduce the diameter of toner in order to realize high-precision images. However, in the case of a simple size reduction with the conventional particle size distribution, the problem of contamination of the carrier and the photoconductor and scattering of the toner becomes remarkable due to the presence of the fine powder side toner, and it is not possible to realize high image quality and high reliability at the same time. Have difficulty. Therefore, it is necessary to sharpen the particle size distribution and reduce the particle size. The agglomeration / fusion coalescence method can provide a toner excellent in these points.

In a full-color machine, since a desired color is reproduced by laminating color toners, the amount of toner used increases, and it is necessary to mix the toners sufficiently. When mixing colors, it is essential to improve color reproducibility and OHP transparency. Generally, a polyolefin wax is internally added to the release agent component for the purpose of preventing low-temperature offset during fixing.
In addition, a small amount of silicone oil is evenly applied to the fixing roller to improve the high-temperature offset property. For this reason, it is not preferable because silicone oil adheres to the output transfer body, causing sticky discomfort.

For this reason, there has been proposed an oilless fixing toner in which a large amount of a release agent component is included in the toner.
However, the addition of a large amount of release agent helps to improve the releasability to some extent, but the binder component and the release agent component are compatible,
The release agent cannot be uniformly and stably exuded, and it is difficult to obtain peeling stability. In addition, the free component of the release agent may cause charging inhibition. Further, when the dispersibility of the pigment in the toner decreases, the pigment interacts with the release agent to form a pigment aggregate, which causes problems such as OHP transparency inhibition and color development inhibition.

In order to improve the releasability of the sheet to be fixed,
A method has been proposed in which a crosslinking component is added to a binder resin to improve cohesion. However, since the melt viscosity of the binder resin increases, the smoothness of the fixed image surface is impaired, and the gloss and OHP of the fixed image are reduced. Transparency is reduced, and sufficient color mixing may not be obtained in a full-color image.

Further, a method has been proposed to improve the apparent cohesive strength of the binder resin by adding a high molecular weight component, but the entanglement density of the binder resin was not controlled by adjusting the amount of the crosslinking agent. It has been difficult to stably achieve both releasability and OHP transparency.

[0016]

DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned problems and, when forming an image on a transparent transfer member, forms an image having excellent smoothness, transparency, color mixing and coloring. It is an object of the present invention to provide a method for forming a high-quality and highly-reliable image with excellent non-fixing sheet releasability and HOT resistance (hot offset property).

[0017]

Means for Solving the Problems The inventors of the present invention have made intensive studies to solve the above-mentioned problems, and as a result, the following means have been adopted to achieve the solution. (1) a step of forming a latent image on an electrostatic latent image holding member, a step of developing the latent image with a developer, and a step of fixing the developed image on a transparent transfer member, wherein the transparent The transfer body has a resin layer on the surface, and the developer uses a toner containing at least a binder resin and a colorant, and a crosslink density M of the toner obtained by a temperature dispersion measurement method in dynamic viscoelasticity.
e is 1.6 × 10 ^{−8 to} 3.5 × 10 ⁻⁶ / Kmol, and the gloss Gs of the fixing surface when fused and fixed on the transparent transfer member is 80% or more. Image forming method.

(2) The colorant is at least one of yellow, magenta, and cyan.
(1) The method for forming an image according to the above. (3) The method for forming an image according to (1) or (2), wherein the colorant in the toner has an average particle size of 0.5 μm or less. (4) The image forming method as described in any one of (1) to (3) above, wherein the toner is manufactured by a coagulation / fusion / coalescence method. (5) The image forming method as described in any one of (1) to (4) above, wherein the toner contains at least one or more release agents.

(6) The transparent transfer member is a transparent film containing a polyester polymer, a styrene / acrylic polymer, a polyamide polymer, a polyimide polymer, or the like. (5) The method for forming an image according to any one of the above (5). (7) The resin layer of the transparent transfer member has a weight average molecular weight of 30,000 or more, preferably 30,000 to 1,000,000, such as a styrene / acrylic copolymer, a polyester copolymer, or a vinyl chloride copolymer. The method for forming an image according to any one of the above (1) to (6), comprising a polymer, a vinyl acetate copolymer or the like. (8) The image forming method according to any one of (1) to (7), wherein the fixing is oil-less fixing. (9) In the fixing step, the fixing temperature is set to 80 to 200 ° C.
The method for forming an image according to any one of (1) to (8), wherein the image is adjusted to the range described in (1).

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention comprises a step of forming a latent image on an electrostatic latent image holding member, a step of developing the latent image with a developer, and a step of fixing the developed image on a transparent transfer member. In the image forming method, the crosslink density Me of the toner determined by the temperature dispersion measurement method in dynamic viscoelasticity is 1.6 × 10 ^{−8 to} 3.5 ×
An appropriate cross-linking (entanglement) structure of the resin of the fixed image is formed by forming a fixed image with a gloss Gs of 80% or more on a transparent transfer member having a resin layer on the surface using a toner of 10 ⁻⁶ / Kmol. It is possible to maintain the hot offset property, and to maintain the mobility of the molecular chains of the resin, and to improve the smoothness of the image surface. Have been improved, and high image quality can be obtained. In particular, it was effective in a full-color image. Crosslink density Me is 3.5 ×
If it exceeds 10 ^-6 / Kmol, low-temperature fixing tends to be difficult, and gloss cannot be obtained.

The toner used in the present invention can be produced, for example, by the following method. That is, an inorganic metal having a charge of at least divalent dissolved in a dispersion medium of a mixture of a resin particle dispersion obtained by dispersing at least resin particles and a colorant dispersion obtained by dispersing a colorant is mixed. A coagulant containing a salt is added to coagulate the resin particles and the colorant to prepare a coagulated particle dispersion for dispersing the coagulated particles. Thereafter, a release agent particle dispersion obtained by dispersing the release agent particles as necessary, and a release agent particles on the surface of the aggregated particles by adding a fine particle dispersion of other components alone or by mixing and adding Fine particles are adhered, and then heated to a temperature equal to or higher than the glass transition point of the resin particles and fused to form toner particles.

In the above-mentioned production method, before the heat fusion step, a resin particle dispersion is further added as necessary, and the resin particles are adhered to the surface of the aggregated particles to prepare the adhered particle dispersion. It is preferred to fuse to form toner particles.

In the aggregation step, the mixed resin particles and the colorant are aggregated by hetero-aggregation or the like to form aggregated particles. In the fusing step, toner particles are formed including colorant particles, resin particles, release agent particles, and the like. In the attaching step, the core-shell structure can be formed by using the aggregated particles as the base particles and uniformly adhering the resin particles to the surface thereof in the dispersion.

In the production of the toner of the present invention, examples of the resin used in the resin particle dispersion include thermoplastic resins. Specific examples thereof include styrene such as styrene, parachlorostyrene, and α-methylstyrene. Homo- or copolymers (styrene resins); methyl acrylate, ethyl acrylate, n-propyl acrylate, n-butyl acrylate, lauryl acrylate, acrylic acid 2
Homopolymers or copolymers (vinyl resins) of esters having a vinyl group such as -ethylhexyl, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, lauryl methacrylate, 2-ethylhexyl methacrylate; acrylonitrile, Homopolymers or copolymers of vinyl nitriles such as methacrylonitrile (vinyl resins); Homopolymers or copolymers of vinyl ethers such as vinyl methyl ether and vinyl isobutyl ether (vinyl resins); vinyl methyl ketone , Vinyl ethyl ketone, vinyl isopropenyl ketone homopolymer or copolymer (vinyl resin); ethylene, propylene, butadiene, isoprene and other olefin homopolymer or copolymer (olefin resin); epoxy Resin, polyester resin, poly Urethane resins, polyamide resins, cellulose resins, non-vinyl condensation resin of polyether resin and the like, and the like graft polymer of these non-vinyl condensation resin and a vinyl monomer and the like. These resins may be used alone or in combination of two or more.

The average particle size of the resin particles in the resin particle dispersion is usually 1 μm or less, preferably 0.01 to 1 μm.
Is appropriate. If the average particle size exceeds 1 μm, the particle size distribution of the finally obtained toner for developing an electrostatic charge image is widened, or free particles are generated, and the performance and reliability of the toner are likely to be reduced. When the average particle size is in the above range, the above disadvantages are eliminated, uneven distribution between toners is reduced, dispersion in the toner is improved, and variations in performance and reliability are advantageously reduced. The average particle diameter can be measured using, for example, a Coulter counter.

The toner used in the present invention is preferably added with a crosslinking agent component in order to impart flexibility to the resin. Specifically, a bifunctional monomer represented by the following general formula is preferred. _{H 2 C = CR-CO-} O-Xn-CO-CR = CH 2 ( wherein, n 3-15 integer, X is CH ₂ or CH ₂ C
H ₂ O and R represent H or CH ₃ . _{) H 2 C = CR-CO} -O-Xn-CH 2 CH 2 O-CO
(Wherein, n an integer of 4 to 14, X is CH _2, R represents H or CH _3.) -CR = CH ₂ The amount of the crosslinking agent component, relative to the weight of the resin 0.1
The range is preferably 1.5 to 1.5% by weight. When the amount is less than 0.1% by weight, although the chargeability is improved, a crosslinked structure is hardly obtained, and the hot offset property may be deteriorated. On the other hand, if it exceeds 1.5% by weight, the fixing property is greatly impaired, which is not preferable.

The crosslinking agent (bifunctional monomer) that can be used in the present invention is not particularly limited as long as it is represented by the above general formula. Examples thereof include ethylene diacrylate, ethylene dimethacrylate, and diacrylic acid. Diethylene glycol, diethylene glycol dimethacrylate, triethylene glycol diacrylate, triethylene glycol dimethacrylate, decaethylene glycol diacrylate,
Decaethylene glycol dimethacrylate, pentaethylene glycol diacrylate, pentaethylene glycol dimethacrylate, pentacontactor diacrylate,
Examples include pentacontactor dimethacrylate, decanediol diacrylate, and decanediol dimethacrylate.

Crosslinked structure (entangled structure) in the present invention
Is determined by measuring a storage elastic modulus G ′, a loss elastic modulus G ″, and a loss tangent tan δ by dynamic viscoelasticity measurement (temperature dispersion measurement) by a sinusoidal vibration method. Specifically, the toner is formed into a tablet. And set it on a parallel plate with a diameter of 8 mm, set the normal force to 0, and set it to 1 rad / sec.
Vibration is given at a vibration frequency of. The measurement starts at 40 ° C and lasts up to 200 ° C. Measurement time interval is 1
For 20 seconds, the rate of temperature rise after the start of measurement is 1 ° C./min. During the measurement, at each measurement temperature, the amount of strain is appropriately maintained and adjusted appropriately so as to obtain an appropriate measurement value.

When a rubber-like flat area (plateau area) is observed, the apparent crosslink density is calculated from the following equation using the value of the storage elastic modulus G 'at the center temperature, and the apparent crosslink density is calculated according to the present invention. Me. Me = G ′ / 3φRT (where, φ: front factor, e: crosslinking reaction rate, M
e: apparent crosslink density, R: gas constant, T: temperature, G '
e: storage elastic modulus of rubbery area

In general, the crosslinking (entanglement) of the molecular chains of the binder resin inside the toner affects the magnitude of the cohesive force of the binder resin itself. That is, since the formation of cross-links (entanglement) restricts the freedom of movement of the molecular chains of the binder itself, the rigidity of the binder resin itself is increased and the meltability of the binder resin itself is reduced. This increase in cross-linking (entanglement) improves the hot offset resistance during fixing, but greatly reduces the glossiness of an image on an OHP sheet or the like.

The toner used in the present invention has a crosslinking density in the range of 1.6 × 10 ^{−8 to} 3.5 × 10 ⁻⁶ / Kmol, preferably 2.0 × 10 ^{−8 to} 3.2 × 10 ^−. The range of ⁶ / Kmol is appropriate, and the crosslink density is 1.6 × 10 ⁻⁸ / Kmo.
If it is less than 1, the hot offset property is reduced because a substantial crosslinked structure is not formed, and 3.5 × 10 ⁻⁶ / Kmol
When the value exceeds, the mobility of the molecular chain of the binder resin itself is inhibited, so that the meltability of the binder resin is reduced, and the smoothness and gloss of the fixed image are deteriorated, or the transparency of the OHP sheet is reduced. There is.

Examples of the colorant for the toner used in the present invention include carbon black, chrome yellow, Hansa yellow, benzidine yellow, slen yellow, quinoline yellow, permanent orange GTR, pyrazolone orange, vulcan orange, watch young red, and permanent. Red, Brilliant Carmine 3B,
Brilliant Carmine 6B, Dupont Oil Red, Pyrazolone Red, Risor Red, Rhodamine B Lake, Lake Red C, Rose Bengal, Aniline Blue, Ultramarine Blue, Calco Oil Blue, Methylene Blue Chloride, Phthalocyanine Blue, Phthalocyanine Green, Malachite Green Oxalate, etc. Pigments: acridine, xanthene, azo, benzoquinone, azine, anthraquinone, dioxazine, thiazine, azomethine, indigo, thioindigo, phthalocyanine, aniline black, polymethine, triphenylmethane And diphenylmethane, thiazole and xanthene dyes. These colorants may be used alone or in combination of two or more.

The average particle size of the colorant particles in the colorant particle dispersion is 1.0 μm or less, preferably 0.01 to 0.5 μm.
A range of 5 μm is appropriate. If the average particle size exceeds 1.0 μm, the particle size distribution of the toner becomes too wide, and free particles are generated, which tends to lower the performance and reliability. When the average particle size is within the above range, the above disadvantages are eliminated, uneven distribution between toners is reduced, dispersion in the toner is improved, and variations in performance and reliability are advantageously reduced. The average particle size can be measured using, for example, a laser diffraction type particle size distribution analyzer. The average particle size of the colorant in the toner is 0.5 μm or less, preferably 0.01 to 0.4 μm.
Is appropriate. Exceeding this range causes problems in the color developability, color reproducibility, OHP transparency and the like of the fixed image. This average particle size can be measured by, for example, a transmission electron microscope (TEM).

The release agent of the toner used in the present invention preferably has poor compatibility with the binder resin. When rich in compatibility, the binder resin is easily plasticized by the release agent,
At the time of high-temperature fixing, the viscosity of the toner is reduced, so that the offset is likely to occur, or the resin particles existing on the surface of the toner are plasticized to lower the glass transition point on the surface of the toner and deteriorate the fluidity of the toner.

Examples of the release agent include low molecular weight polyolefins such as polyethylene, polypropylene and polybutene; silicones having a softening point upon heating; fatty acid amides such as oleamide, erucamide, ricinoleamide and stearamide. And carnauba wax, rice wax, candelilla wax, wood wax,
Vegetable waxes such as jojoba oil; animal waxes such as beeswax; mineral and petroleum waxes such as montan wax, ozokerite, ceresin, paraffin wax, microcrystalline wax, Fischer-Tropsch wax; higher grades such as stearyl stearate and behenyl behenate Ester waxes of fatty acids and higher alcohols; ester waxes of higher fatty acids such as butyl stearate, propyl oleate, glyceride monostearate, glyceride distearate, pentaerythritol tetrabehenate and unit prices or polyhydric lower alcohols; Higher fatty acids such as diethylene glycol monostearate, dipropylene glycol distearate, distearic acid diglyceride, tetrastearic acid triglyceride and polyhydric alcohol multimers Higher fatty acid ester waxes such as sorbitan monostearate; cholesterol higher fatty acid ester waxes such as cholesteryl stearate; these may be used alone or in combination of two or more You may use it.

The average particle size of the release agent particles in the release agent particle dispersion is 1.0 μm or less, preferably 0.01 to 1.0 μm.
The range of m is appropriate. If the average particle size exceeds 1.0 μm, the particle size distribution of the toner becomes too wide, and free particles are generated, which tends to cause deterioration in performance and reliability. When the average particle size is within the above range, the above disadvantages are eliminated, uneven distribution between toners is reduced, dispersion in the toner is improved, and variations in performance and reliability are advantageously reduced. The average particle size can be measured using, for example, a laser diffraction type particle size distribution measuring device, a centrifugal type particle size distribution measuring device, or the like.

The release agent particles are dispersed together with a polymer electrolyte such as an ionic surfactant, a polymer acid, or a polymer base in an aqueous medium such as water, and heated to a temperature equal to or higher than the melting point to generate a strong shearing force. When processing is performed using a homogenizer or a pressure discharge type disperser that can be applied, fine particles of 1.0 μm or less can be easily adjusted. The binder resin constituting the resin particles of the toner is not particularly limited in combination with the colorant and the release agent, and can be appropriately selected depending on the purpose.

The toner according to the present invention may be used in a dispersion of a resin particle, a dispersion of a colorant, a dispersion of a release agent, and / or a mixed dispersion thereof according to the purpose. It is possible to disperse other components (particles) such as an organic powder, a lubricant, and an abrasive. Examples of the internal additive include metals such as ferrite, magnetite, reduced iron, cobalt, manganese, and nickel, alloys, and magnetic substances such as compounds containing these metals.

As the charge controlling agent, for example, a quaternary ammonium salt compound, a nigrosine compound, a dye comprising a complex of aluminum, iron, chromium and the like, a triphenylmethane pigment and the like can be used. In addition, as the charge control agent in the present invention, a material which is hardly dissolved in water is preferable in order to control ionic strength which affects stability at the time of aggregation and fusion and to suppress contamination of wastewater.

Examples of the inorganic powder include silica,
All particles usually used as an external additive on the surface of a toner, such as titania, calcium carbonate, magnesium carbonate, tricalcium phosphate, and cerium oxide, can be used. As the organic powder, for example, all particles usually used as an external additive on the surface of a toner, such as a vinyl resin, a polyester resin, and a silicone resin, can be used. In addition, these inorganic powders and organic powders can also be used as a flow aid, a cleaning aid, and the like.

Examples of the lubricant include fatty acid amides such as ethylenebisstearic acid amide and oleic acid amide, and fatty acid metal salts such as zinc stearate and calcium stearate. Examples of the abrasive include the above-mentioned silica, alumina, cerium oxide and the like.

The average particle size of the other components is 1.0 μm.
m, preferably in the range of 0.01 to 1.0 μm. When the average particle size exceeds 1.0 μm, the particle size distribution of the toner is too wide to generate free particles, which tends to cause deterioration in performance and reliability. When the average particle size is within the above range, the above disadvantages are eliminated, uneven distribution between toners is reduced, dispersion in the toner is improved, and variations in performance and reliability are advantageously reduced. The average particle size can be measured using, for example, a laser diffraction type particle size distribution measuring device, a centrifugal type particle size distribution measuring device, or the like.

When the resin particle dispersion, the colorant dispersion and the release agent dispersion are mixed, the content of the colorant is 50% by weight.
The following are suitable, preferably in the range of 2 to 40% by weight. Also, the content of the release agent is 50% by weight or less,
Preferably, the range of 2 to 40% by weight is appropriate. Further, the content of other components may be such that the object of the present invention is not impaired, and is generally extremely small, specifically in the range of 0.01 to 5% by weight, preferably 0.1 to 5% by weight. 5-2
A weight percent range is appropriate.

Examples of the dispersion medium of the resin particle dispersion, the colorant dispersion, the release agent dispersion, and the dispersion of other component particles include an aqueous medium. Examples of the aqueous medium include water such as distilled water and ion-exchanged water, and alcohol. These may be used alone or in combination of two or more.

It is preferable that a surfactant is added to and mixed with the aqueous medium. This surfactant is advantageous in ensuring the dispersion stability of the particles and the storage stability of the dispersion. And it is also effective for the stability of the aggregated particles in the aggregation step. As the surfactant, for example, anionic surfactants such as sulfate, sulfonate, phosphate, and soap;
Amine surfactants such as amine salt type and quaternary ammonium salt type; and nonionic surfactants such as polyethylene glycol-based, alkylphenol ethylene oxide adduct-based and polyhydric alcohol-based surfactants. Of these, ionic surfactants are preferred, and anionic surfactants and cationic surfactants are more preferred. The nonionic surfactant is preferably used in combination with an anionic surfactant or a cationic surfactant. The surfactants may be used alone or in combination of two or more.

Specific examples of the anionic surfactant include:
Fatty acid soaps such as potassium laurate, sodium oleate, castor oil sodium; sulfates such as octyl sulfate, lauryl sulfate, lauryl ether sulfate, nonylphenyl ether sulfate; lauryl sulfonate, dodecylbenzene sulfonate, triisopropylpyrnaphthalene sulfonate;
Sulfonates such as sodium alkylnaphthalene sulfonate such as dibutylnaphthalene sulfonate, naphthalene sulfonate formalin condensate, monooctyl sulfosuccinate, dioctyl sulfosuccinate, lauric amide sulfonate, oleic amide sulfonate; lauryl phosphate, isopropyl phosphate, nonyl Phosphate esters such as phenyl ether phosphate; dialkyl sulfosuccinates such as dioctyl sodium sulfosuccinate; and sulfosuccinates such as disodium lauryl sulfosuccinate.

Specific examples of the cationic surfactant include:
Amine salts such as laurylamine hydrochloride, stearylamine hydrochloride, oleylamine acetate, stearylamine acetate, stearylaminopropylamine acetate; lauryl trimethyl ammonium chloride, dilauryl dimethyl ammonium chloride, distearyl ammonium chloride, distearyl dimethyl ammonium Quaternary such as chloride, lauryldihydroxyethylmethylammonium chloride, oleylbispolyoxyethylenemethylammonium chloride, lauroylaminopropyldimethylethylammonium ethosulfate, lauroylaminopropyldimethylhydroxyethylammonium perchlorate, alkylbenzenedimethylammonium chloride, alkyltrimethylammonium chloride A Such as Moniumu salts and the like.

Specific examples of the nonionic surfactant include:
Alkyl ethers such as polyoxyethylene octyl ether, polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, and polyoxyethylene oleyl ether; alkyl phenyl ethers such as polyoxyethylene octyl phenyl ether and polyoxyethylene nonyl phenyl ether; poly Alkyl esters such as oxyethylene laurate, polyoxyethylene stearate, and polyoxyethylene oleate; polyoxyethylene lauryl amino ether, polyoxyethylene stearyl amino ether, polyoxyethylene oleyl amino ether, polyoxyethylene soy amino ether, polyoxyethylene Alkyl amines such as oxyethylene tallow amino ether; polyoxyethylene lauric amide, polyoxy Chirensutearin acid amides, alkyl amides such as polyoxyethylene oleic acid amide;
Vegetable oil ethers such as polyoxyethylene castor oil ether and polyoxyethylene rapeseed oil ether; alkanolamides such as lauric acid diethanolamide, stearic acid diethanolamide and oleic acid diethanolamide; polyoxyethylene sorbitan monolaurate and polyoxyethylene Sorbitan monopalmiate,
And sorbitan ester ethers such as polyoxyethylene sorbitan monostearate and polyoxyethylene sorbitan monooleate.

Further, in order to improve the dispersion stability of the colorant in an aqueous medium, as a dispersion aid for lowering the energy of the colorant in the toner, titanate coupling agents, rosin, water-soluble polymers, etc. Can be used.

The coagulant used in the coagulation step is 2
Inorganic metal salts having a charge of at least valence are mentioned. A general inorganic metal compound or a polymer thereof is used by dissolving it in a fine resin particle dispersion, and the metal element constituting the inorganic metal salt is 2A, 3A, 4A, 5A in the periodic table (long period table).
It has two or more valence charges belonging to the groups A, 6A, 7A, 8, 1B, 2B, and 3B, and is dissolved in the form of ions in an aggregation system of resin fine particles. Specific examples include calcium chloride, calcium nitrate, barium chloride,
Metal salts such as magnesium chloride, zinc chloride, aluminum chloride, and aluminum sulfate; and inorganic metal salt polymers such as polyaluminum chloride, polyaluminum hydroxide, and calcium polysulfide. Among them, an aluminum salt and a polymer thereof are particularly preferable. Generally, in order to obtain a sharper particle size distribution, even if the valence of the inorganic metal salt is monovalent to divalent, divalent to trivalent, trivalent to tetravalent, and the same valence, the polymerization type is Inorganic metal salt polymers are more suitable.

The content of the surfactant in the dispersion is as follows:
It is sufficient if it does not inhibit the present invention, and generally a small amount is sufficient. Specifically, the range is 0.01 to 10% by weight, preferably 0.05 to 5% by weight, more preferably 0.1 to 2% by weight. If the content is less than 0.01% by weight, dispersions such as resin particle dispersions, colorant dispersions, and release agent dispersions become unstable, causing agglomeration, and the stability between the particles during aggregation. Therefore, there are problems such as release of specific particles. If it exceeds 10% by weight,
It is not preferable because the particle size distribution of the particles becomes too wide and the control of the particle size becomes difficult.

The method for preparing the resin particle dispersion is not particularly limited and may be appropriately selected depending on the intended purpose. For example, it can be adjusted as follows. The resin constituting the resin particles is a homopolymer or copolymer (vinyl-based resin) of vinyl monomers such as esters, vinyl nitriles, vinyl ethers, and vinyl ketones having a vinyl group.
In the case of, a vinyl monomer is subjected to emulsion polymerization or seed polymerization in an ionic surfactant to obtain a dispersion of homopolymer or copolymer (vinyl resin) particles of the vinyl monomer. Adjustment is preferred.

When the resin constituting the resin particles is a resin other than the homopolymer or copolymer of the vinyl monomer,
If the resin is soluble in an oily solvent having relatively low solubility in water, the resin is dissolved in the oily solvent, and then added to the water together with the ionic surfactant or polymer electrolyte, and a homogenizer or the like is added. It is preferable that the dispersion is adjusted by heating or reducing the pressure to evaporate the oily solvent after dispersing the fine particles into fine particles using the dispersing device.

The colorant dispersion can be adjusted, for example, by dispersing the colorant in an aqueous medium such as a surfactant. The release agent dispersion is, for example, dispersing the release agent in water together with a polymer electrolyte such as an ionic surfactant, a polymer acid, or a polymer base, and then heating the mixture to a temperature equal to or higher than its melting point, using a homogenizer or a pressure discharger. By applying a strong shearing force using a mold disperser, the release agent can be made finer and adjusted.

The particle dispersion of other components can be adjusted, for example, by dispersing in a water-based medium such as a surfactant together with a colorant. The dispersing means is not particularly limited. For example, a dispersing device known per se, such as a rotary shearing homogenizer or a ball mill having a medium, a sand mill, or a dyno mill can be used.

In the toner of the present invention, the color image density can be increased by increasing the amount of the pigment added to the toner, and a toner having a desired color tone can be obtained. In addition, the dispersibility of the pigment in the toner is important for improving the smoothness, transparency, color mixing, and coloring of a transparent film image. The above-described toner manufacturing method can obtain a toner having a small average particle size and a sharp particle size distribution, unlike the case of manufacturing by a kneading and pulverizing method.

The developer used in the present invention is not particularly limited except that it contains the above-mentioned toner, and may contain appropriate components according to the purpose. That is, the toner may be used alone to prepare a one-component electrostatic image developer, or may be used in combination with a carrier to prepare a two-component electrostatic image developer. The carrier is not particularly limited. For example, JP-A-62-39879 and JP-A-56-11
A known carrier such as a resin-coated carrier described in JP-A-461 or the like can be used.

Specific examples of the carrier include the following resin-coated carriers. That is, examples of the core particles of the carrier include ordinary iron powder, ferrite, and a molded product of magnetite, and the average particle size is suitably in the range of 30 to 200 μm. Examples of the carrier coating resin include styrenes such as styrene, parachlorostyrene and α-methylstyrene, methyl acrylate, ethyl acrylate, n-propyl acrylate, lauryl acrylate, 2-ethylhexyl acrylate, methacrylic acid Α-methylene fatty acid monocarboxylic acids such as methyl, n-propyl methacrylate, lauryl methacrylate, 2-ethylhexyl methacrylate; nitrogen-containing acrylics such as dimethylaminoethyl methacrylate; vinyl nitriles such as acrylonitrile and methacrylonitrile; -Vinyl pyridine,
Vinyl pyridines such as 4-vinyl pyridine; vinyl ethers such as vinyl methyl ether and vinyl isobutyl ether; vinyl ketones such as vinyl methyl ketone, vinyl ethyl ketone and vinyl isopropenyl ketone; olefins such as ethylene and propylene; Vinylidene, tetrafluoroethylene, homopolymers such as vinyl fluorine-containing monomers such as hexafluoroethylene, or copolymers of two or more monomers, and silicones such as methyl silicone and methyl phenyl silicone;
Examples include polyesters containing bisphenol, glycol, and the like, epoxy resins, polyurethane resins, polyamide resins, cellulose resins, polyether resins, polycarbonate resins, and the like. These resins may be used alone or in combination of two or more. The coating resin amount is
The range is 0.1 to 10 parts by weight, preferably 0.5 to 3.0 parts by weight, per 100 parts by weight of the core particles.

For the production of the carrier, a heating type kneader, a heating type Henschel mixer, a UM mixer, or the like can be used. Depending on the amount of the coating resin, a heating type fluidized bed, a heating type kiln, or the like may be used. Can be. The mixing ratio of the toner and the carrier in the developer is not particularly limited, and can be appropriately selected according to the purpose.

The transparent transfer member used in the present invention is styrene.
A film such as an acrylic copolymer or a polyester copolymer can be used. The thickness of this film is suitably in the range of 0.1 to 0.2 mm. Further, the transparent transfer member of the present invention has a resin coating layer containing a resin having a weight average molecular weight of 30,000 or more, preferably 30,000 to 1,000,000. If the weight-average molecular weight is less than 30,000, the resin coating layer will be remarkably melted at the time of fixing, resulting in a poor fixed image. Specific examples of the resin of the resin coating layer include styrene
There are acrylic polymers, polyester polymers, vinyl chloride polymers, vinyl acetate polymers and the like. These are excellent in light transmittance, workability, and the like. The thickness of this resin coating layer is in the range of 0.1 to 0.3 μm, preferably 0.1 to 0.3 μm.
A range of 2 μm is appropriate.

The image forming method of the present invention includes an electrostatic latent image forming step, a toner image forming step, a transfer step, and a cleaning step. Each of the steps is a general step per se, for example, as described in JP-A-56-40868 and JP-A-49-91.
231 and the like. The image forming method of the present invention can be carried out by using a known image forming apparatus such as a copying machine or a facsimile machine.

The step of forming an electrostatic latent image is a step of forming an electrostatic latent image on an electrostatic latent image carrier, and the step of forming a toner image is a step of developing the electrostatic latent image with a developer layer on a developer carrier. To form a toner image. The developer layer is not particularly limited as long as it contains the toner according to the present invention. The transfer step is a step of transferring the toner image onto the transfer member, and the cleaning step is a step of removing the electrostatic image developer remaining on the electrostatic latent image carrier.

The fixing temperature at the time of fixing in the image forming step is preferably in the range of 80 to 200 ° C. If the temperature is too low, the toner does not melt sufficiently and a good fixed image cannot be obtained.
On the other hand, if it is too high, problems such as offset to the heat roll occur.

[0064]

EXAMPLES The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples. In the following, “parts” means parts by weight. The glossiness of the transparent film on which the toner was melt-fixed was measured using a gloss meter manufactured by Murakami Color Materials Co., Ltd. Average particle size and average volume particle distribution of toner GSDv
Is a Coulter Counter (TA2
(Type). The average particle size of the resin particles, colorant particles, and release agent particles was measured using a laser diffraction type particle size distribution analyzer (LA-700, manufactured by Horiba, Ltd.).

The evaluation of the electrostatic image developer was carried out by oilless fixing using a modified machine of VIVACE400 manufactured by Fuji Xerox Co., Ltd., image formation at a fixing temperature of 160 ° C., and smoothness and transparency of the obtained image. , Color development, and color mixing were visually evaluated. The smoothness was determined to be poor if it was rough due to irregularities or the like, and good if no such condition was observed. Transparency was determined to be poor if the transmitted light was turbid, and good if no such condition was observed.
The color developability was determined to be poor when the intermediate color was light, and good when clear. The color mixing property was determined to be bad if there was turbidity in the color overlapped portion of two or more colors, and good if clear. For hot offset properties, an image was formed at a fixing temperature of 200 ° C. in the same manner as described above, and the offset state of the obtained image was examined.

—Preparation of Resin Particle Dispersion (1) — Styrene 350 parts Butyl acrylate・ 50 parts Acrylic acid 8 parts Carbon tetrabromide 4 parts (all , Wako Pure chemical Industries, Ltd.) crosslinking agent (manufactured by Shin-Nakamura chemical Co.,; NK ester) ... 2 parts of _{H 2 C = CR-CO-} O- (CH 2) 9 -OCH 2 -C
O-CH = CH _{2 A} solution is prepared by mixing and dissolving the above-mentioned components. On the other hand, 8 parts of a nonionic surfactant (Nonipol 8.5, manufactured by Sanyo Chemical Co., Ltd.) and an anionic surfactant (Daiichi Kogyo Seiyaku) 3 parts of ammonium persulfate (manufactured by Wako Pure Chemical Industries, Ltd.) was dissolved in 585 parts of ion-exchanged water, dispersed and emulsified in a flask, and slowly mixed for 10 minutes. After dissolving 50 parts of ion-exchanged water and purging with nitrogen, the contents in the flask were heated in an oil bath until the contents reached 70 ° C. while stirring, and emulsion polymerization was continued for 6 hours. Thereafter, the reaction solution was cooled to room temperature to prepare a resin particle dispersion. Next, a part of the resin particle dispersion was left on an oven at 80 ° C. to remove water, and the properties of the residue were measured. The average particle diameter of the resin particles was 150 nm, the glass transition point was 57 ° C., The weight average molecular weight was 45,000.

-Preparation of Resin Particle Dispersion (2)-Styrene ... 350 parts Butyl acrylate ...・ 50 parts Acrylic acid 8 parts Carbon tetrabromide 4 parts (all , Wako Pure chemical Industries, Ltd.) crosslinking agent (manufactured by Shin-Nakamura chemical Co.,; NK ester) ... 10 parts of _{H 2 C = CR-CO-} O- (CH 2) 9 -OCH 2 -C
O-CH = CH _{2 A} solution is prepared by mixing and dissolving the above-mentioned components. On the other hand, 8 parts of a nonionic surfactant (Nonipol 8.5, manufactured by Sanyo Chemical Co., Ltd.) and an anionic surfactant (Daiichi Kogyo Seiyaku) 3 parts of ammonium persulfate (manufactured by Wako Pure Chemical Industries, Ltd.) was dissolved in 585 parts of ion-exchanged water, dispersed and emulsified in a flask, and slowly mixed for 10 minutes. After dissolving 50 parts of ion-exchanged water and purging with nitrogen, the contents in the flask were heated in an oil bath until the contents reached 70 ° C. while stirring, and emulsion polymerization was continued for 6 hours. Thereafter, the reaction solution was cooled to room temperature to prepare a resin particle dispersion. Next, a part of the resin particle dispersion was left on an oven at 80 ° C. to remove water, and the characteristics of the residue were measured. The average particle size of the resin particles was 145 nm, the glass transition point was 57 ° C., The weight average molecular weight was 47,000.

—Preparation of Resin Particle Dispersion (3) — Styrene 350 parts Butyl acrylate・ 50 parts Acrylic acid 8 parts Carbon tetrabromide 4 parts (all , Wako Pure chemical Industries, Ltd.) crosslinking agent (manufactured by Shin-Nakamura chemical Co.,; NK ester) ... 0.3 parts of _{H 2 C = CR-CO-} O- (CH 2) 9 -OCH 2 -C
O-CH = CH _{2 A} solution is prepared by mixing and dissolving the above-mentioned components. On the other hand, 8 parts of a nonionic surfactant (Nonipol 8.5, manufactured by Sanyo Chemical Co., Ltd.) and an anionic surfactant (Daiichi Kogyo Seiyaku) 3 parts of ammonium persulfate (manufactured by Wako Pure Chemical Industries, Ltd.) was dissolved in 585 parts of ion-exchanged water, dispersed and emulsified in a flask, and slowly mixed for 10 minutes. After dissolving 50 parts of ion-exchanged water and purging with nitrogen, the contents in the flask were heated in an oil bath until the contents reached 70 ° C. while stirring, and emulsion polymerization was continued for 6 hours. Thereafter, the reaction solution was cooled to room temperature to prepare a resin particle dispersion. Then, a part of the resin particle dispersion was left on an oven at 80 ° C. to remove water, and the properties of the residue were measured. The average particle diameter of the resin particles was 140 nm, the glass transition point was 57 ° C., The weight average molecular weight was 43,000.

—Preparation of Colorant Dispersion (1) — Phthalocyanine Pigment 70 parts (PVFASTBLUE, manufactured by Dainichi Seika Co., Ltd.) Anionic surfactant・ ・ 3 parts (manufactured by Wako Pure Chemical Industries) bis (dioctyl pyrophosphate) oxyacetate titanate (manufactured by Shin-Etsu Chemical Co., Ltd.) ・ ・ ・ ・ ・ ・ ・ 3 parts ion-exchanged water .. 300 parts The above components were mixed and dissolved, and a homogenizer (manufactured by IKA,
(Ultra Turrax) and the average particle size is 16
A cyan colorant dispersion liquid (1) having a thickness of 0 nm was prepared.

—Preparation of Colorant Dispersion (2) — Magenta Pigment 70 parts (Quinacridone R122, manufactured by Dainichi Seika Co., Ltd.) Anionic surfactant・ ・ ・ ・ ・ ・ 3 parts (Wako Pure Chemical Industries) Ion-exchanged water ・ ・ ・ ・ ・ 300 parts The above components were mixed and dissolved, and a homogenizer (IKA Corporation,
(Ultra Turrax) and the average particle size is 16
A cyan colorant dispersion (2) having a thickness of 0 nm was prepared.

—Preparation of Colorant Dispersion Solution (3) — Yellow Pigment 70 parts (Chromofine Yellow PY93, manufactured by Dainichi Seika Co., Ltd.) Anionic surfactant・ ・ ・ ・ ・ ・ 3 parts (Wako Pure Chemical Industries) Ion exchange water ・ ・ ・ ・ 300 parts The above components were mixed and dissolved, and a homogenizer (IKA Corporation,
(Ultra Turrax) and the average particle size is 16
A cyan colorant dispersion (3) having a thickness of 0 nm was prepared.

—Preparation of Release Agent Particle Dispersion— Paraffin Wax 100 parts (HNP0190, manufactured by Nippon Seiro, melting point 90 ° C.) Anionic surfactant 3.5 parts (Lipall 860K, manufactured by Lion) Ion-exchanged water 500 parts The above components were mixed and dissolved, and a homogenizer (manufactured by IKA) was used.
(Ultra Turrax), followed by dispersion treatment with a pressure discharge type homogenizer to prepare a release agent particle dispersion having an average particle diameter of 180 nm.

Example 1 (Preparation of Agglomerated Particle Dispersion) Resin Particle Dispersion (1) 300 parts Colorant Dispersion (1) 300 ... 15 parts Release agent particle dispersion liquid ... 25 parts Zinc chloride ... 1 part Ion exchange water ... -500 parts The above-mentioned components are accommodated in a round stainless steel flask, and a homogenizer (Ultra Turrax T50, manufactured by IKA) is used.
Then, the mixture was heated in an oil bath for heating while stirring to 55 ° C. After maintaining at 55 ° C. for 30 minutes, when observed with an optical microscope, the average particle size was about 4.8 μm.
It was confirmed that m aggregated particles were formed.

(Preparation of Adhered Particle Dispersion) To the aggregated particle dispersion, gently add 70 parts of the resin particle dispersion (1), and further raise the temperature of the heating oil bath to 56 ° C. and add 1 part.
Hold for hours. Observation with an optical microscope confirmed that adhered particles having an average particle size of about 5.4 μm were formed.

(Fusing of Adhered Particles) The pH of the dispersion of adhered particles at 56 ° C. was 2.5.
A 1N aqueous solution of NaOH was added to the dispersion to adjust the pH at 56 ° C. to 6.5 to stabilize the adhered particles. Then, the dispersion was heated to 95 ° C. with continuous stirring, and then maintained for 6 hours. The attached particles were fused. The reaction product was filtered, washed sufficiently with ion-exchanged water, and dried with a vacuum drier to obtain toner particles.

(Evaluation of Toner Particles) The average particle diameter of the obtained toner particles was 5.4 μm, and the GSDv was 1.23. One part of colloidal silica (R972, manufactured by Nippon Aerosil Co., Ltd.) was externally added to 100 parts of the toner particles, and mixed with a Henschel mixer to obtain a toner for developing an electrostatic image. The obtained toner crosslink density was measured by a dynamic viscoelasticity temperature dispersion measurement method to be 6.5 ×.
It was 10 ^-7 / Kmol. Transmission electron microscope (TE
When the cross section of the toner particles was observed in M), the average particle size of the pigment particles was 300 nm.

(Preparation of an electrostatic image developer) 100 parts of ferrite particles (manufactured by Powder Tech, average particle size: 50 μm) and a methacrylate resin (manufactured by Mitsubishi Rayon Co., Ltd., molecular weight: 95,
000) and 1.5 parts of toluene were placed in a pressure kneader together with 500 parts of toluene, and the mixture was stirred and mixed at room temperature for 15 minutes. Thereafter, the mixture was heated to 70 ° C. while mixing under reduced pressure to distill off toluene, and then cooled, and cooled to 105 μm. And then classified using a sieve to prepare a resin-coated carrier. This resin-coated carrier and the toner were mixed to prepare a two-component electrostatic image developer having a toner concentration of 7% by weight.

(Evaluation of Image) A transparent film made of polyethylene terephthalate provided with a 0.2 μm thick resin layer of a styrene / methyl methacrylate copolymer having a weight average molecular weight of 50,000 using this electrostatic image developer. An image was formed and the image quality was evaluated. As a result, the surface gloss, smoothness, coloring, color mixing, and transparency were good, and the gloss Gs was 9
It was 0%. Also, the hot offset property was good.

Example 2 (Preparation of Aggregated Particle Dispersion) Resin Particle Dispersion (1) 300 parts Colorant Dispersion (2) ... 15 parts Release agent particle dispersion liquid ... 25 parts Zinc chloride ... 1 part Ion exchange water ... -500 parts The above-mentioned components are accommodated in a round stainless steel flask, and a homogenizer (Ultra Turrax T50, manufactured by IKA) is used.
Then, the mixture was heated in an oil bath for heating while stirring to 55 ° C. After being kept at 55 ° C. for 30 minutes, when observed with an optical microscope, the average particle size was about 5.2 μm.
It was confirmed that m aggregated particles were formed.

(Preparation of Adhered Particle Dispersion) To the agglomerated particle dispersion, gently add 150 parts of the resin particle dispersion (1), and further raise the temperature of the heating oil bath to 56 ° C.
Hold for hours. Observation with an optical microscope confirmed that adhered particles having an average particle size of about 5.7 μm were formed.

(Fusing of Adhered Particles) The pH of the adhered particle dispersion at 56 ° C. was measured to be 3.0.
A 1N aqueous solution of NaOH was added to the dispersion to adjust the pH at 56 ° C. to 8.0 to stabilize the adhered particles. Then, the dispersion was heated to 93 ° C. while stirring, and then kept for 5 hours. The attached particles were fused. The reaction product was filtered, washed sufficiently with ion-exchanged water, and dried with a vacuum drier to obtain toner particles.

(Evaluation of Toner Particles) The average particle diameter of the obtained toner particles was 5.6 μm, and the GSDv was 1.21. One part of colloidal silica (R972, manufactured by Nippon Aerosil Co., Ltd.) was externally added to 100 parts of the toner particles, and mixed with a Henschel mixer to obtain a toner for developing an electrostatic image. When the obtained toner crosslink density was measured by a dynamic viscoelasticity temperature dispersion measurement method, it was 6.0 ×.
It was 10 ^-7 / Kmol. Transmission electron microscope (TE
When the cross section of the toner particles was observed in M), the average particle size of the pigment particles was 280 nm.

(Preparation of electrostatic image developer) 100 parts of ferrite particles (manufactured by Powder Tech, average particle size: 50 μm) and methacrylate resin (manufactured by Mitsubishi Rayon Co., Ltd., molecular weight: 95,
000) and 1.5 parts of toluene were placed in a pressure kneader together with 500 parts of toluene, and the mixture was stirred and mixed at room temperature for 15 minutes. Thereafter, the mixture was heated to 70 ° C. while mixing under reduced pressure to distill off toluene, and then cooled, and cooled to 105 μm. And then classified using a sieve to prepare a resin-coated carrier. This resin-coated carrier and the toner were mixed to prepare a two-component electrostatic image developer having a toner concentration of 7% by weight.

(Evaluation of Image) A transparent film made of polyethylene terephthalate provided with a 0.2 μm thick resin layer of a styrene / methyl methacrylate copolymer having a weight average molecular weight of 50,000 using this electrostatic image developer. An image was formed and the image quality was evaluated. As a result, the surface gloss, smoothness, coloring, color mixing, and transparency were good, and the gloss Gs was 9
5%. Also, the hot offset property was good.

Example 3 Preparation of Aggregated Particle Dispersion Resin Particle Dispersion (1) 300 parts Colorant Dispersion (3) 15 parts Release agent dispersion liquid 25 parts Polyaluminum hydroxide 1 part (Paho2S, manufactured by Asada Chemical Co., Ltd.) Ion-exchanged water .. 500 parts The above components were placed in a round stainless steel flask and homogenized (Ultra Turrax T50, manufactured by IKA).
Then, the mixture was heated in an oil bath for heating while stirring to 55 ° C. After maintaining at 55 ° C. for 30 minutes, when observed with an optical microscope, the average particle size was about 5.9 μm.
It was confirmed that m aggregated particles were formed.

(Preparation of Adhered Particle Dispersion) To this aggregated particle dispersion, gently add 50 parts of the resin particle dispersion (1), and further raise the temperature of the heating oil bath to 56 ° C.
Hold for hours. Observation with an optical microscope confirmed that adhering particles having an average particle size of about 6.1 μm were formed.

(Fusion of Adhered Particles) The pH of the adhered particle dispersion at 56 ° C. was 2.7.
A 1N aqueous solution of NaOH was added to the dispersion to adjust the pH at 56 ° C. to 8.0 to stabilize the adhered particles. Then, the dispersion was heated to 93 ° C. with continuous stirring, and then kept for 7 hours. The attached particles were fused. The reaction product was filtered, washed sufficiently with ion-exchanged water, and dried with a vacuum drier to obtain toner particles.

(Evaluation of Toner Particles) The average particle size of the obtained toner particles was 5.1 μm, and the GSDv was 1.19. One part of colloidal silica (R972, manufactured by Nippon Aerosil Co., Ltd.) was externally added to 100 parts of the toner particles, and mixed with a Henschel mixer to obtain a toner for developing an electrostatic image. The crosslinking density of the obtained toner is
When measured by the temperature dispersion measurement method of dynamic viscoelasticity, it was 5.4.
× 10 ^-7 / Kmol. Transmission electron microscope (TE
When the cross section of the toner particles was observed in M), the average particle size of the pigment particles was 340 nm.

(Preparation of an electrostatic image developer) 100 parts of ferrite particles (manufactured by Powder Tech, average particle size 50 μm) and a methacrylate resin (manufactured by Mitsubishi Rayon Co., Ltd., molecular weight 95,
000) and 1.5 parts of toluene were placed in a pressure kneader together with 500 parts of toluene, and the mixture was stirred and mixed at ordinary temperature for 15 minutes. And then classified using a sieve to prepare a resin-coated carrier. This resin-coated carrier and the toner were mixed to prepare a two-component electrostatic image developer having a toner concentration of 7% by weight.

(Evaluation of Image) A transparent film made of polyethylene terephthalate provided with a 0.2 μm thick resin layer of a styrene / methyl methacrylate copolymer having a weight average molecular weight of 50,000 using this electrostatic image developer. An image was formed and the image quality was evaluated. As a result, the surface gloss, smoothness, coloring, color mixing, and transparency were good, and the gloss Gs was 8
3%. Also, the hot offset property was good.

Comparative Example 1 (Preparation of Aggregated Particle Dispersion) Resin Particle Dispersion (2) 300 parts Colorant Dispersion (2) 15 parts Release agent dispersion liquid 25 parts Zinc chloride 1 part Ion-exchanged water 500 parts Stored in a round stainless steel flask and homogenized (IKA Ultra Turrax T50)
Then, the mixture was heated in an oil bath for heating while stirring to 55 ° C. After maintaining at 55 ° C. for 30 minutes, when observed with an optical microscope, the average particle size was about 4.8 μm.
It was confirmed that m aggregated particles were formed.

(Preparation of Adhered Particle Dispersion) To the aggregated particle dispersion, gently add 70 parts of the resin particle dispersion (2), and further raise the temperature of the heating oil bath to 56 ° C. and add 1 part.
Hold for hours. Observation with an optical microscope confirmed that adhered particles having an average particle size of about 5.4 μm were formed.

(Fusion of Adhered Particles) The pH of the dispersion of adhering particles at 56 ° C. was 2.5.
1N NaOH aqueous solution was added to this dispersion to adjust the pH at 56 ° C. to 6.0 to stabilize the adhered particles. Then, the dispersion was heated to 93 ° C. while stirring, and then kept for 5 hours. The attached particles were fused. The reaction product was filtered, washed sufficiently with ion-exchanged water, and dried with a vacuum drier to obtain toner particles.

(Evaluation of Toner Particles) The average particle size of the obtained toner particles was 5.1 μm, and the GSDv was 1.19. One part of colloidal silica (R972, manufactured by Nippon Aerosil Co., Ltd.) was externally added to 100 parts of the toner particles, and mixed with a Henschel mixer to obtain a toner for developing an electrostatic image. The crosslinking density of the obtained toner is
When measured by the temperature dispersion measurement method of dynamic viscoelasticity, it was 7.0.
× 10 ^-5 / Kmol. Transmission electron microscope (TE
When the cross section of the toner particles was observed in M), the average particle size of the pigment particles was 360 nm.

(Preparation of electrostatic image developer) 100 parts of ferrite particles (manufactured by Powder Tech, average particle size 50 μm) and methacrylate resin (manufactured by Mitsubishi Rayon Co., Ltd., molecular weight 95,
000) and 1.5 parts of toluene were placed in a pressure kneader together with 500 parts of toluene, and the mixture was stirred and mixed at room temperature for 15 minutes. Thereafter, the mixture was heated to 70 ° C. while mixing under reduced pressure to distill off toluene, and then cooled, and cooled to 105 μm. And then classified using a sieve to prepare a resin-coated carrier. This resin-coated carrier and the toner were mixed to prepare a two-component electrostatic image developer having a toner concentration of 7% by weight.

(Evaluation of Image) A transparent film made of polyethylene terephthalate provided with a 0.2 μm thick resin layer of a styrene-methyl methacrylate copolymer having a weight average molecular weight of 50,000 using this electrostatic image developer. When an image was formed and the image quality was evaluated, the surface gloss was poor,
Smoothness is slightly rough, coloration is slightly thin, color mixing is turbid, transparency is slightly turbid, and gloss G
s was 46%. Further, the hot offset property was good.

Comparative Example 2 (Preparation of Agglomerated Particle Dispersion) Resin Particle Dispersion (3) 300 parts Colorant Dispersion (2) 15 parts Release agent dispersion liquid 25 parts Zinc chloride 1 part Ion-exchanged water 500 parts Stored in a round stainless steel flask and homogenized (IKA Ultra Turrax T50)
Then, the mixture was heated in an oil bath for heating while stirring to 55 ° C. After being kept at 55 ° C. for 30 minutes, when observed with an optical microscope, the average particle size was about 5.2 μm.
It was confirmed that m aggregated particles were formed.

(Preparation of Adhered Particle Dispersion) To this aggregated particle dispersion, gently add 150 parts of the resin particle dispersion (3), and further raise the temperature of the oil bath for heating to 2 ° C. at 56 ° C.
Hold for hours. Observation with an optical microscope confirmed that adhered particles having an average particle size of about 5.7 μm were formed.

(Fusion of Adhered Particles) The pH of the dispersion of adhered particles at 56 ° C. was 3.0.
A 1N aqueous solution of NaOH was added to the dispersion to adjust the pH at 56 ° C. to 8.0 to stabilize the adhered particles. Then, the dispersion was heated to 93 ° C. while stirring, and then kept for 5 hours. The attached particles were fused. The reaction product was filtered, washed sufficiently with ion-exchanged water, and dried with a vacuum drier to obtain toner particles.

(Evaluation of Toner Particles) The average particle diameter of the obtained toner particles was 5.1 μm, and the GSDv was 1.20. One part of colloidal silica (R972, manufactured by Nippon Aerosil Co., Ltd.) was externally added to 100 parts of the toner particles, and mixed with a Henschel mixer to obtain a toner for developing an electrostatic image. The crosslinking density of the obtained toner is
When measured by the temperature dispersion measurement method of dynamic viscoelasticity, 8.2 was obtained.
× 10 ^-9 / Kmol. Transmission electron microscope (TE
When the cross section of the toner particles was observed in M), the average particle size of the pigment particles was 310 nm.

(Preparation of an electrostatic image developer) 100 parts of ferrite particles (manufactured by Powder Tech, average particle size: 50 μm) and a methacrylate resin (manufactured by Mitsubishi Rayon Co., Ltd., molecular weight: 95,
000) and 1.5 parts of toluene were placed in a pressure kneader together with 500 parts of toluene, and the mixture was stirred and mixed at ordinary temperature for 15 minutes. And then classified using a sieve to prepare a resin-coated carrier. This resin-coated carrier and the toner were mixed to prepare a two-component electrostatic image developer having a toner concentration of 7% by weight.

(Evaluation of Image) A transparent film made of polyethylene terephthalate provided with a 0.2 μm thick resin layer of a styrene-methyl methacrylate copolymer having a weight average molecular weight of 50,000 using this electrostatic image developer. An image was formed and the image quality was evaluated. As a result, the surface gloss, smoothness, coloring, color mixing, and transparency were good, and the gloss Gs was 9
3%. However, hot offset occurred at 180 ° C.

[0103]

[Table 1]

[0104]

According to the present invention, it is possible to form a fixed image having excellent smoothness, transparency, color mixing property and coloring property by adopting the above-mentioned constitution, and to improve the releasability of a non-fixed sheet.
It has excellent HOT resistance (hot offset property) and enables highly reliable image formation. In particular, it has become possible to easily and simply form a high-quality and highly reliable image in forming a full-color image.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Manabu Serizawa 1600 Takematsu, Minamiashigara-shi, Kanagawa Prefecture Inside Fuji Xerox Co., Ltd. Inventor Shuji Sato 1600 Takematsu, Minamiashigara-shi, Kanagawa Prefecture F-term in Fuji Xerox Co., Ltd. (Reference) 2H005 AA01 AA21 CA17 CA21 DA04 DA06 EA10

Claims (2)

[Claims] 1. An image forming method comprising: forming a latent image on an electrostatic latent image holding member, developing the latent image with a developer, and fixing the developed image on a transparent transfer member.
The transparent transfer body has a resin layer on the surface, the developer,
Using a toner containing at least a binder resin and a colorant,
The crosslink density Me of the toner determined by the temperature dispersion measurement method in dynamic viscoelasticity is from 1.6 × 10 ^{−8 to} 3.5 × 10 ⁻⁶ / K.
wherein the gloss Gs of the fixing surface when melt-fixed on the transparent transfer member is 80% or more. 2. The image forming method according to claim 1, wherein said fixing is oil-less fixing.