JPH04291358A - Production of toner - Google Patents

Abstract

PURPOSE:To easily produce the toner forming images which are sharp regardless of a relatively small content of coloring agents and have good transparency particularly with a fewer production stages and further to produce the toner having excellent functions and multilayered structures at a low cost. CONSTITUTION:Resin fine particles 2 are added into a solvent which does not dissolve the resin fine particles 2 to execute solvent dispersion 6 and a particle mixture consisting of the coloring agents 3, etc., is added thereto to produce the resin fine particles 8 stuck with the coloring agents. The internal nucleus particles 5 are then produced by using raw materials consisting of a binder resin 1, etc. The internal nucleus particles 5 are then subjected to an external addition treatment 6 to stick the resin fine particles 3 stuck with the coloring agents, etc., to the surfaces thereof, by which the internal nucleus particles 7 externally added with the resin fine particles are produced. The internal nucleus particles 7 externally added with the resin fine particles are subjected to a film forming treatment 8 by bringing a solvent 4 dissolving the resin fine particles into contact therewith to form the resin film layers 12, by which the final toner 13 formed with the resin films contg. the coloring agents is produced.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a dry developing toner used in electrophotography, and more particularly to a method for producing a toner having a multilayer structure.

0002

2. Description of the Related Art Many conventional electrophotographic methods have been proposed based on the Carlson process shown in US Pat. No. 2,297,691. Generally, an electrostatic latent image is formed on a photoreceptor using a photoconductive substance, and then a fine powder called "toner" is selectively attached to the electrostatic latent image and development is performed. The image is visualized, transferred to a transfer material such as paper as necessary, and then fixed by heat and pressure, solvent vapor, etc. to obtain an image-formed product.

[0003] Development methods can be broadly classified into dry development methods and liquid development methods. Further, as dry development methods, two-component development methods using a carrier such as a magnetic brush development method and a cascade development method are known. Further, as one-component development methods, there are known jumping development methods, FEED development methods, magnetic brush development methods, and the like. The toners used in these development methods are further classified into insulating and conductive toners. Generally, the toner used in these development methods is made by dispersing colorants such as dyes and pigments and charge control agents in resin, and having various substances adhered to the surface of fine particles of approximately 10 μm. has been done.

[0004] Generally known methods for producing toner include a kneading and pulverizing method, a spray drying method, and a polymerization method. In addition, various methods for attaching various substances to the toner surface include methods such as applying heat using a fluidized drying oven, applying mechanical force using a mixer such as a ball mill, and polymerization methods. There are known methods to do this. For details, refer to the resin melt-coated toner (Japanese Patent Application Laid-Open No. 1-22
7163), interfacial polymerization microencapsulated toner (JP-A-1-167850), colorant-containing resin externally added toner (
JP-A-64-10263), etc.

[0005]

[Problems to be Solved by the Invention] However, as a prior art toner and toner manufacturing method,
In the toner shown in JP-A-1-167850, the external additives easily peel off, resulting in poor image quality of the image formed product and staining the inside of the image forming apparatus.In addition, the toner manufacturing method shown in JP-A-1-167850 uses interfacial polymerization. There are restrictions on the raw materials used in the toner, and the toner shown in JP-A-1-227163 and the toners used conventionally contain a colorant in the inner core particles, but the colorant is hidden by a binder resin etc. The amount of coloring agent must be increased because the color cannot be clearly seen. In this case, light is blocked by the colorant, so when a colorant other than black is used, the transparency required as a color toner characteristic is poor, and the image becomes unclear. Furthermore, if the amount of colorant is large, when used as a two-component developing toner, the colorant is likely to elute onto the magnetic carrier surface during continuous image formation, so-called bleed-out, which may cause deterioration of toner properties and defects during transfer. It has the following drawbacks.

SUMMARY OF THE INVENTION The object of the present invention is to solve the above-mentioned problems, and to provide a clear and transparent image with a small amount of colorant, toner properties that do not deteriorate during toner transportation or storage, and to prevent the inside of the device from being damaged. Toner that has the property of not staining
This provides an easy manufacturing method with fewer steps.

[0007]

[Means for Solving the Problems] The toner manufacturing method of the present invention provides a toner that is used in a dry development method and has a resin coating layer formed on the surface of core particles made of at least a binder resin using at least a colorant and fine resin particles. In this step, a resin coating layer containing at least a coloring agent is formed by attaching resin fine particles having at least a coloring agent on the surface thereof and then treating with a solvent that dissolves the resin fine particles. Features.

Further, the toner manufacturing method of the present invention is characterized in that at least the coloring agent is attached to the surface of the resin fine particles in a wet manner.

[0009]

[Operation] In the toner manufacturing method of the present invention, mixed particles such as a coloring agent are attached to the surface of fine resin particles by a wet method. The principle of this method is to use electrical adsorption force, chemical adsorption force, physical adsorption force, etc. to attach the material. When the adhesion is carried out using the above method, mixed particles such as a colorant are uniformly dispersed on the surface of the resin fine particles, and the particles are adhered to the resin fine particles without any local deviation. At this time, by appropriately selecting raw materials, conditions, methods, etc., it is possible to control the amount of the coloring agent, etc. attached to the surface of the resin fine particles. Next, mixed particles such as fine resin particles are attached to the surface of the inner core particles using a dry method or a wet method. The principle of this method is
In the dry method, mutual collision motion is repeated between each particle, and the energy given at the time of collision forms a local active region, and the physical adsorption force or chemical adsorption force generated there causes fine resin particles etc. to be formed on the surface of the inner core particle. This method involves attaching mixed particles of . In addition, the wet method is similar to the method in which a coloring agent or the like is attached to the surface of the resin fine particles. When the adhesion is carried out by the above method, mixed particles such as fine resin particles are uniformly dispersed on the surface of the inner core particles, and the particles are attached to the inner core particles without any local deviation. Next, by dissolving the resin fine particles with a solvent, a resin coating layer containing various fine particles is formed on the surface of the inner core particle. Therefore, the adhesion and uniformity of the resin coating layer to the inner core particles are improved,
Furthermore, it fixes additives such as colorants and prevents them from peeling off. At this time, by controlling the dissolution time of the resin particles by selecting the type of solvent and the contact time between the particles and the solvent,
It is possible to prevent the solvent from penetrating into the inner core particles. Therefore, even if, for example, the inner core particles have a lower softening point and are softer than the fine resin particles, the resin coating layer can be reliably formed, and aggregation and granulation of toner particles can be suppressed.

Further, in the toner obtained by the toner manufacturing method of the present invention, a resin coating layer is formed using at least a coloring agent and fine resin particles on the surface of the inner core particles made of at least a binder resin. That is, since the colorant is present near the surface of the toner, the colorant is also present near the surface of the image when an image is formed. Therefore, since the colorant is hardly hidden by the binder resin or the like, a clear image is formed despite the small amount of colorant. Furthermore, in a color toner using something other than black as a colorant, the less the colorant, the less the transmitted light will be blocked, so an image with good transparency, which is an important characteristic of color toners, can be obtained.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1(a) is a flowchart of the toner manufacturing method of the present invention, and FIG. 1(b) is a schematic diagram of the toner of the present invention. In the toner manufacturing method, first, the resin particles 2 are added to a solvent that does not dissolve the resin particles 2, and solvent dispersion 6 is performed, and mixed particles consisting of the colorant 3, etc. are added thereto, and an adhesion treatment 7 is performed to form the colorant-attached resin. Fine particles 8 are produced. Next, inner core particles 5 are prepared by a kneading and pulverizing method, a spray drying method, a polymerization method, etc. using raw materials consisting of a binder resin 1, etc., and external additives such as colorant-attached resin fine particles 8 are attached to the surface of the inner core particles 5. Processing 9 is performed to produce inner core particles 10 treated with external addition of resin fine particles. Next, a coating treatment 11 is performed by bringing the resin fine particle externally added inner core particles 10 into contact with a solvent 4 that dissolves the resin fine particles, thereby forming a resin coating layer 12 on the surface of the inner core particles 5, thereby forming a colorant-containing resin. In this process, a coated toner 13 is manufactured.

The inner core particles 5 used in the present invention are composed of at least a binder resin 1, and toner components can be added thereto as required. As the toner component, one or more types can be selected from inorganic agents, charge control agents, magnetic powders, conductive agents, mold release agents, dispersants, etc., as required. Moreover, these can be attached to the surface of the resin fine particles 2 together with the coloring agent 3 as needed, and incorporated into the resin coating layer 12. Methods for producing the inner core particles 5 include commonly used kneading and pulverization methods, spray drying methods, polymerization methods, and the like. The shape may be either spherical or amorphous, and the particle size is generally 1 to 1.
A 40 μm one is used.

Wet methods for attaching the coloring agent 3 and the like to the surface of the resin microparticles 2 include a heterocoagulation method that utilizes electrostatic adhesion due to the zeta potential difference between the surface of the resin microparticles 2 and the surface of the colorant 3 and other microparticles; A wet milling method in which a mixed dispersion in which the resin particles 2 and the colorant 3 are dispersed in a solvent that does not dissolve the resin particles 2 is milled using a ball mill, sand mill, etc., and the resin particles 2 are treated with a coupling agent and then colored. A coupling agent method or the like in which the adhesion treatment 7 is performed by mixing with agent 3 or the like can be used. Specifically, the solvent used at this time includes petroleum solvents such as hexane, heptane, Isopar, and kerosene, and water. Furthermore, anionic, cationic, nonionic surfactants, etc. may be added to improve dispersibility.

[0014] As a method for attaching the resin fine particles 2 to the surface of the inner core particles 5, either a dry method or a wet method can be used. As a dry type, a conventional mixer such as a ball mill or a V-type mixer can be used, but it is preferable to use a so-called high-speed fluidized mixer. As the high-speed fluidized stirrer, a so-called Henschel mixer, Mechano Fusion System (Hosokawa Micron), Nara Hybridization System (Nara Kikai Seisakusho), Mechano Mill (Okada Seiko), etc. are used. However, the apparatus for attaching the resin fine particles 2 to the surface of the inner core particles 5 is not limited to these. As a wet method, the above-mentioned method can be used.

Methods for carrying out the coating treatment 11 with the solvent 4 include a spray drying method and a liquid immersion method, but any method may be used as long as the contact time can be controlled. Preferably, a powder coating device such as Dispercoat (Nissin Seifun) or Coatmizer (Freund Sangyo) is used.

The raw material for the binder resin 1 is not particularly limited, and commonly used materials can be used. In detail, polystyrene and its copolymers include hydrogenated styrene resin, ABS resin, ASA resin,
AS resin, AAS resin, ACS resin, AES resin, styrene-p-chlorostyrene copolymer, styrene-propylene copolymer, styrene-butadiene crosslinked polymer, styrene-butadiene-chlorinated paraffin copolymer, styrene-allyl Alcohol copolymers, styrene-butadiene rubber emulsions, styrene-maleic acid ester copolymers, styrene-isobutylene copolymers, styrene-maleic anhydride copolymers, etc., acrylate resins or methacrylate resins, and their copolymers. In addition, styrene-acrylic resins and their copolymers include styrene-acrylic copolymers, styrene-diethylaminoethyl methacrylate copolymers, styrene-butadiene-acrylic acid ester copolymers, and styrene-methyl methacrylate copolymers. Coalescence, styrene-n-butyl methacrylate copolymer, styrene-methyl methacrylate-n-butyl acrylate copolymer, styrene-methyl methacrylate-butyl arylate-N-(ethoxymethyl)acrylamide copolymer, styrene-glycidyl Methacrylate copolymer, styrene-butadiene-
Dimethylaminoethyl methacrylate copolymer, styrene-acrylic acid ester-maleic ester copolymer, styrene-methyl methacrylate-acrylic acid-2
- ethylhexyl copolymer, styrene-n-butyl arylate-ethyl glycol methacrylate copolymer,
Styrene-n-butyl methacrylate-acrylic acid copolymer, styrene-n-butyl methacrylate-maleic anhydride copolymer, styrene-butyl acrylate-
Isobutyl maleic acid half ester-divinylbenzene copolymer, etc., polyester and its copolymers, polyethylene and its copolymers, epoxy resins, silicone resins, polypropylene and its copolymers, fluororesins, polyamide resins, polyvinyl alcohol resins , polyurethane resin, polyvinyl butyral resin, etc., and if necessary, one type or a mixture of two or more types of these can be used. Moreover, wax etc. can also be used as a substance other than resin. For more information, please see plant-based natural waxes such as candelilla wax, carnauba wax, and rice wax, animal-based natural waxes such as beeswax and lanolin, mineral-based natural waxes such as montan wax and ozokerite, and natural natural waxes such as paraffin wax, microcrystalline wax, and petrolatum. Petroleum waxes, polyethylene waxes, synthetic hydrocarbon waxes such as Fischer-Tropsch waxes, modified waxes such as montan wax derivatives and paraffin wax derivatives, hydrogenated waxes such as hydrogenated castor oil and hydrogenated castor oil derivatives, waxes such as synthetic waxes, and stearin. acids, higher fatty acids such as palmitic acid, polyolefins such as low molecular weight polyethylene, polyethylene oxide, and polypropylene, olefin copolymers such as ethylene-acrylic acid copolymers, ethylene-acrylic acid ester copolymers, and ethylene-vinyl acetate copolymers. There are polymers, etc., and one type or two or more types of these can be used as necessary.

[0017] In detail, the colorant 3 includes carbon black, spirit black, copper oxide, manganese dioxide, aniline black, activated carbon, nigrosine, yellow lead, zinc yellow,
Cadmium yellow, yellow iron oxide, mineral fast yellow, nickel titanium yellow, navels yellow, naphthol yellow S, banzer yellow G, banzer yellow 10G, benzidine yellow G, benzidine yellow GR, quinoline yellow lake, tartrazine lake, permanent yellow NCG , red yellow lead, molybdenum orange, pyrazolone orange, permanent orange GTR, Vulcan orange, industhrene brilliant orange RK, industhrene brilliant orange GK, benzidine orange G, red iron, cadmium red, red lead, mercury sulfide, cadmium, permanent red 4R , Lysol Red, Pyrazolone Red, Lake Red D, Brilliant Carmine 6B, Brilliant Carmine 3B, Eosin Lake, Rhodamine Lake B, Alizarin Lake, Manganese Purple, Fast Violet B
, Methyl Violet Lake, Cobalt Blue, Alkali Blue Lake, Victoria Blue Lake, Phthalocyanine Blue, Fast Sky Blue, Industhrene Blue BC, Pigment Green B, Malachite Green Lake, Final Yellow Green G, Zinc White, Titanium Oxide, Zinc Sulfide , phthalocyanine, rhodamine B lake, Solar Pure Yellow 8G, quinacridone, polytungstophosphoric acid, methylene blue, rose bengal, sulfonamide derivative, C.I. I. Direct black 19,
22, 28, 154, 168, C. I. Direct Yellow 12, 26, 86, 87, 130, 142, C. I
．． Direct Red 9, 13, 17, 23, C. I. Direct Blue 78, 86, 199, C. I. Assid Black 52, 172, 208, C. I. Ashido Yellow 23, 25, C. I. Ashido Red 52, 254
, 289, C. I. Ashido Blue 9, 254, C. I
．． Food Black 2, C. I. Solvent yellow 2,
6, 14, 15, 16, 19, 21, 33, 56, 61
, 80, C. I. Solvent Orange 1, 2, 5, 6,
14, 37, 40, 44, 45, C. I. Solvent red 1, 3, 8, 23, 24, 25, 27, 30, 49
, 81, 82, 83, 84, 100, 109, 121,
C. I. Disperse Red 9, C. I. Solvent Violet 8, 13, 14, 21, 27, C. I. Disperse Violet 1, C. I. Solvent blue 2
, 11, 12, 25, 35, 36, 55, 73, C. I
．． Solvent Green 3, C. I. Solvent Brown 3, 5, 20, 37, C. I. Solvent black 3,
5, 22, 23, etc., and these can be used singly or in a mixture of two or more, if necessary.

Further, as a dispersing agent, metal soap, polyethylene glycol, etc. are added, and as a charge control agent, an electron-accepting organic complex, chlorinated polyester, nitrofnic acid, quaternary ammonium salt, pyridinyl salt, etc. are added as necessary. can do.

In addition, magnetic powders such as Fe3O4, Fe2O3, Fe, Cr, Ni, etc. can be used as the magnetic toner.

[0020] As the inorganic fine particles, Si02, TiO
2 (rutile, anatase), Zn0, Al2O3 (α type, β type), TiON, TiBaO3, MgO, ZrO2
, CaCO3, NiO, SnO, clay, talc, silica sand, mica, SiN, SiC, Ba2SO4, carbon black, and other fine particles can be used.

As the resin fine particles 2, polymethyl methacrylate (PM) prepared by emulsion polymerization method, emulsion polymerization method without adding emulsifier, seed polymerization method, dispersion polymerization method, suspension polymerization method, etc.
MA), polyethyl methacrylate (PEMA), poly-n-butyl methacrylate (PBMA), polyester, styrene-butadiene copolymer, polyvinyl chloride (PVC), polyvinyl alcohol (PVA), polyvinyl acetate (PVAc) , poly-γ-methylglutamate, fluororesin, vinylidene fluoride resin, benzoquanamine resin, silicone resin, epoxy resin, nylon 6
Fine particles of 6/6, nylon 11, nylon 12, polystyrene resin, crosslinked polystyrene resin, phenol resin, melamine resin, polyolefin resin, polyethylene resin, cellulose resin, etc. can be used.

The solvent 4 used in coating the surface of the inner core particle 5 is not particularly limited as long as it dissolves the fine resin particles 2 attached to the surface of the inner core particle 5 by the method described above. For details, see n-hexane, heptane, cyclohexane, benzene, toluene, xylene, dichloromethane, chloroform, tetrachloromethane, dichloroethane, chlorobenzene, nitromethane, acetonitrile, acrylonitrile, tetrahydrofuran, dioxane, methylcellosolve, ethyl acetate, butyl acetate, acetone. , methyl ethyl ketone, methanol,
Examples include ethanol, propanol, benzyl alcohol, pyridine, diethylformamide, dimethylformamide, etc., and these can be used singly or in combination of two or more as required.

By using the raw materials described above and forming the resin coating layer 11 containing the colorant 3 by the method described above, there is no need for operations such as classification after treatment, and the storage stability is excellent. 3 is located near the surface of the toner, it is possible to produce a colorant-containing resin-coated toner 13 with a clear image and good transparency despite the small amount of colorant.

This embodiment will be explained in more detail below. The numbers in the following Examples and Comparative Examples indicate parts by weight unless otherwise specified.

[Example 1] <Preparation of inner core particles> A styrene-acrylic copolymer was used as the binder resin. This was melt-kneaded using a screw extruder, cooled, and then coarsely ground. Next, it is finely pulverized with a jet pulverizer and classified to have an average particle size of 9 μm and a particle size distribution of 5 to 20.
A μm-sized inner core particle was prepared.

<Adhesion of colorant to the surface of resin fine particles> Resin fine particles...PBMA (particle size 0.4 μm)/9.5
Colorant: Nables Yellow/0.5 Solvent: Water/1,000.0 The above composition was stirred and mixed in a ball mill. Then, particles were obtained by spray drying using a spray drying method. When the obtained particles were observed under an electron microscope, it was confirmed that Nabel's Yellow was attached to the surface of the PBMA fine particles without peeling off.

<Attachment of colorant-attached resin particles to inner core particles> Colorant-attached PBMA particles...15.0 Inner core particles...85.
0 Using the mixture having the above composition, colorant-attached PBMA fine particles were attached to the surface of the inner core particles using a mechanofusion system (manufactured by Hosokawa Micron). Attachment speed is 1500 rpm
The treatment was carried out under the following conditions: m, treatment time 30 minutes. When the obtained particles were observed using an electron microscope, it was confirmed that the colorant-attached PBMA fine particles adhered to the surface of the inner core particles without peeling off. In addition, when cross-sectional observation was performed using an electron microscope, it was found that the colorant adhered to the surface of the inner core particle.
It was confirmed that the MA fine particles remained embedded in a spherical shape.

<Coating treatment> The inner core particles added to the outside of the fine particles prepared by the above method were subjected to a coating treatment. Xylene was used as the solvent. The xylene dispersion air stream and the particle dispersion air stream were brought into contact for a contact time of 1.0 seconds, and then spray-dried at a drying temperature of 60°C to evaporate the xylene. The particles obtained by this coating treatment had no binding between particles, and each particle was an aggregate in an independent state. Further, when the cross section of the particles produced in this example was observed using an electron microscope, a resin coating layer with a thickness of 0.2 μm was formed on the surface of the inner core particle, and Nables Yellow was uniformly dispersed in the resin coating layer. was confirmed.

When the toner produced by the above method was loaded into a laser printer equipped with a one-component non-contact developing machine and an OPC photoreceptor, and an image was formed using paper as the toner transfer material, a clear image was obtained. was able to form. Furthermore, when a similar test was conducted using an OHP transparent sheet as a toner transfer material, clear images with good transparency were formed. Furthermore, after conducting a durability test of 30,000 sheets,
I was able to obtain clear images just like in the beginning. In addition, the toner produced in this example was sealed in a container and stored for three months in an environment with a temperature of 30°C and a humidity of 80%, and then a similar test was conducted, but there was no aggregation, and a clear image similar to the initial image was obtained. I was able to do that.

[Comparative Example 1] <Preparation of colorant-containing inner core particles> Binder resin: styrene-acrylic copolymer/98.0
Colorant: Nables Yellow/2.0 The above composition was treated in the same manner as in Example 1 to obtain particles. When the cross section of the obtained particles was observed using an electron microscope, it was observed that Nables Yellow was uniformly dispersed in the resin.

<Adhesion of fine resin particles> Fine resin particles...PBMA (particle size 0.4 μm)/15.
0 Colorant-containing inner core particles...85.0 A mixture having the above composition was deposited in the same manner as in Example 1. The obtained particles were in the same state as in Example 1.

<Coating treatment> The inner core particles added to the outer part of the fine particles prepared by the above method were subjected to a coating treatment. The treatment method was the same as in Example 1. When the obtained particles were observed with an electron microscope, it was confirmed that a resin coating layer with a thickness of 0.2 μm was uniformly formed on the surface of the inner core particle.

When the toner produced by the above method was loaded into the laser printer used in Example 1 and an image was formed using paper as a toner transfer material, there was no aggregation of the toner, but the amount of colorant was Even though the amount was larger than that in Example 1, a pale and unclear image was formed. Furthermore, when a similar test was conducted using an OHP transparent sheet as a toner transfer material, the transparency was poor, and a blurred image with pale colors was formed. [Example 2] <Preparation of inner core particles> Binder resin 1...paraffin wax/50.0 Binder resin 2...polyethylene wax/50.0 The above composition was kneaded using a batch kneader and cooled. After that, it is coarsely pulverized, then finely pulverized with a jet pulverizer, and then classified to have an average particle size of 10 μm.
, inner core particles with a particle size distribution of 5 to 25 μm were prepared.

<Attachment of colorant to resin fine particles> Example 1
The same composition and method were used. However, Lysol Red was used as the coloring agent. When the obtained particles were observed with an electron microscope, they were found to be in the same state as in Example 1.

<Attachment of colorant-attached resin particles to inner core particles> Inner core particles...85.0 Colorant-attached PBMA particles...15.0 Solvent...Water/1,000.0 The above composition After stirring and mixing at room temperature for 10 hours and adhering by a heteroaggregation method, the mixture was dried by a spray drying method to obtain particles. The obtained particles were in the same state as in Example 1.

<Coating treatment> Xylene was used as the solvent. The conditions for coating and spray drying were the same as in Example 1. As in Example 1, the obtained particles had no binding between the particles and were an aggregate of independent particles. Furthermore, when the obtained particles were cross-sectionally observed using an electron microscope, it was confirmed that a resin coating layer with a thickness of 0.3 μm was formed on the surface of the inner core particle, and Lysol Red was uniformly dispersed therein.

When the toner produced by the above method was loaded into the laser printer used in Example 1 and an image was formed using paper as the toner transfer material, a clear image was formed at a low fixing temperature of 120°C. I was able to do that. Furthermore, when a similar test was conducted using an OHP transparent sheet as a toner transfer material, clear images with good transparency were formed at a fixing temperature of 120°C. Furthermore, when we conducted a durability test of 30,000 sheets, we were able to obtain clear images just like the initial one. Furthermore, the toner produced in this example was sealed in a container and stored for three months in an environment with a temperature of 30°C and a humidity of 80%, and a similar test was conducted, but there was no aggregation, and the image was as clear as the initial one. I was able to get it.

[Example 3] <Preparation of inner core particles> Binder resin 1... Candelilla wax/60.0 Binder resin 2... Polyethylene wax/40.0 Using the above composition, Example Inner core particles were obtained in the same manner as in 1. The inner core particles after classification have an average particle size of 9 μm and a particle size distribution of 5 to 2
It was 0 μm.

<Adhesion of colorant to resin particles> Resin particles...Styrene-butadiene copolymer (particle size 0.2 μm)
m)/10.0 Colorant: Cobalt blue/0.2 Coupling agent: Amine-based silane coupling agent/
4.0 Solvent: Water/1,000.0 The above composition was mixed and stirred at 60° C. for 10 hours to perform attachment by a coupling method, and then dried by a spray drying method to obtain particles. When the obtained particles were observed under an electron microscope, it was confirmed that cobalt blue was uniformly adhered to the surface of the resin fine particles.

<Attachment of colorant-adhered resin particles to inner core particles> Inner core particles...8.0 Colorant-adhered resin particles...2.0 Solvent...Water/500.0 The above composition was milled in a ball mill. After mixing and stirring for 10 hours, the mixture was spray dried by a spray drying method to obtain particles. The obtained particles were in the same state as in Example 1.

<Coating treatment> Tetrahydrofuran was used as a solvent. The conditions for coating treatment and spray drying are as in Example 1.
I did the same thing. As in Example 1, the obtained particles had no binding between the particles and were an aggregate of independent particles. Furthermore, when the obtained particles were cross-sectionally observed using an electron microscope, it was confirmed that a resin coating layer with a thickness of 0.1 μm was formed on the surface of the inner core particle, and cobalt blue was uniformly dispersed therein.

When the toner produced by the above method was loaded into the laser printer used in Example 1 and an image was formed using paper as the toner transfer material, a clear image was formed at a low fixing temperature of 110°C. I was able to do that. Furthermore, when a similar test was conducted using an OHP transparent sheet as a toner transfer material, clear images with good transparency were formed at a fixing temperature of 110°C. Furthermore, when we conducted a durability test of 30,000 sheets, we were able to obtain clear images just like the initial one. Furthermore, the toner produced in this example was sealed in a container and stored for three months in an environment with a temperature of 30°C and a humidity of 80%, and a similar test was conducted, but there was no aggregation, and the image was as clear as the initial one. I was able to get it.

[Example 4] <Preparation of inner core particles> Inner core particles were prepared using the same composition and method as in Example 1.

<Adhesion of colorant to resin fine particles> Resin fine particles...PMMA fine particles (particle size 0.3 μm)/10.0 Colorant...aniline black/0.2 Solvent...water/
1,000.0 The above composition was mixed and stirred for 24 hours, adhered by a heteroaggregation method, and then dried by a spray drying method to obtain particles. When the obtained particles were observed with an electron microscope, they were found to be in the same state as in Example 1.

<Adhesion to inner core particles> Inner core particles...Styrene-acrylic copolymer/50.0
Colorant-attached PMMA fine particles...10.0 Toner components...
...Fe3O4/40.0 Deposition was carried out in the same manner as in Example 1 using the above composition. When the obtained particles were observed with an electron microscope, it was found that the colorant was attached to the surface of the inner core particles.
It was confirmed that the MMA fine particles and Fe3O4 were uniformly attached.

<Coating treatment> Toluene was used as a solvent. The coating treatment and spray drying conditions were the same as in Example 1. When we observed the cross section of the obtained particles using an electron microscope, we found that
A resin coating layer with a thickness of 0.2 μm is formed on the surface of the inner core particle, and aniline black and Fe3O are further added to the resin coating layer.
It was confirmed that 4 was uniformly dispersed.

When the toner produced by the above method was loaded into a laser printer having a one-component magnetic brush developer and an OPC photoreceptor and an image was formed using paper as a toner transfer material, a clear image was formed. was completed. Furthermore, when we conducted a durability test of 30,000 sheets, we were able to obtain clear images just like the initial one. Furthermore, the toner produced in this example was sealed in a container and stored for three months in an environment with a temperature of 30°C and a humidity of 80%, and a similar test was conducted, but there was no aggregation, and the image was as clear as the initial one. I was able to get it.

[Comparative Example 2] Aniline black and PMMA fine particles with a particle size of 0.3 μm were attached to the surface of the inner core particle prepared in Example 4 using the same composition and method as in Example 1. Created. When the obtained particles were observed under an electron microscope, it was observed that PMMA and aniline black were uniformly attached to the surface of the inner core particle.

When the toner produced by the above method was directly loaded into the laser printer used in Example 1 and an image was formed using paper as the toner transfer material, the inside of the developing machine was damaged due to the poor fluidity of the toner. This caused aggregation, and the externally added particles fell off, contaminating the inside of the device. Furthermore, the obtained image had background fog and was unclear.

[Example 5] <Preparation of inner core particles> Inner core particles were prepared using the same raw materials and method as in Example 1. The average particle size and particle size distribution after classification were the same as in Example 1.

<Adhesion of colorant to resin fine particles> Resin fine particles...PMMA fine particles (particle size 0.2 μm)/10.0 Colorant...C. I. Direct Blue 78/1.5 Solvent...Water/1,500.0 The above composition was mixed and stirred at 60°C for 24 hours, adhered by a heteroaggregation method, and then dried by a spray drying method to form particles. I got it. The obtained particles were in the same state as in Example 1.

<Attachment of colorant-attached resin particles to inner core particles> Inner core particles...90.0 Colorant-attached PMMA particles...10.0 Using the above composition, the same method and conditions as in Example 1 were used. Attachment was performed using When the obtained particles were observed with an electron microscope, it was confirmed that the colorant-attached PMMA fine particles were attached to the surface of the inner core particles without being peeled off. Further, when the cross section was observed using an electron microscope, it was observed that the colorant-adhered PMMA fine particles were embedded in the surface of the inner core particles while remaining spherical.

<Coating treatment> Toluene was used as a solvent. The toluene dispersion air stream and the particle dispersion air stream were brought into contact for 1.0 seconds, and then the toluene was evaporated by spray drying at a drying temperature of 70°C. The particles obtained by this coating treatment had no binding between particles, and each particle was an aggregate in an independent state. Furthermore, when the cross section of the particles produced in this example was observed using an electron microscope, a resin coating layer with a thickness of 0.15 μm was formed on the surface of the inner core particle, and a resin coating layer with a thickness of 0.15 μm was formed on the surface of the inner core particle.
．． I. It was confirmed that Direct Blue 78 was uniformly dispersed.

When the toner produced by the above method was loaded into the laser printer used in Example 1 and an image was formed using paper as a toner transfer material, a clear image could be formed. In addition, OHP can be used as a toner transfer material.
When a similar test was conducted using a transparent sheet, clear images with good transparency were formed. Furthermore, when we conducted a durability test of 30,000 sheets, we were able to obtain clear images just like the initial one. In addition, the toner produced in this example was sealed in a container and stored for three months in an environment with a temperature of 30°C and a humidity of 80%, and then a similar test was conducted, but there was no aggregation, and a clear image similar to the initial image was obtained. I was able to do that.

[Example 6] <Preparation of inner core particles> Inner core particles were prepared using the same composition and method as in Example 1. The average particle size and particle size distribution after classification were the same as in Example 1.

<Attachment of Colorant to Resin Fine Particles> Particles of three colors were prepared using cobalt blue, navels yellow, and resol red as colorants. Its composition is shown below. The conditions for attachment were the same as in Example 1.

Resin fine particles...PBMA (particle size 0.4 μm)/9.5
Colorant...0.5 Solvent...Water/1,000.0 <Adhesion of colorant-attached resin particles to inner core particles> Colorant-attached PBMA particles...15.0 Inner core particles...85.
0 The above composition was deposited using the same method and conditions as in Example 1. All three types of obtained particles were in the same state as in Example 1.

<Coating treatment> A resin coating treatment was carried out in the same manner as in Example 1. The three types of particles obtained were aggregates in which each particle was independent, with no binding between particles. Furthermore, cross-sectional observation of the particles produced in this example using an electron microscope revealed that a resin coating layer with a thickness of 0.2 μm was formed on the surface of the three types of inner core particles, and the coloring agent was uniformly dispersed in the resin coating layer. It was confirmed that

The three color toners prepared in the above manner mixed with carriers were repeatedly developed and transferred three times using a two-component magnetic brush developing machine and a laser printer equipped with an OPC photoreceptor to form a full-color image. was formed. The mixing ratio of toner and carrier was 10.0 parts by weight of toner and 90.0 parts by weight of carrier. When a full color image was formed using paper as a toner transfer material, 3
A clear image with good color reproducibility in the color and the two-color mixed portion was formed. Further, when a full-color image was formed using an OHP transparent sheet as a toner transfer material, a clear image with good color reproducibility and transparency in the mixed color portion was formed, just like when using paper. Furthermore, when we conducted a durability test of 30,000 sheets, no bleed-out occurred and we were able to obtain clear images just like the initial one.

Although the embodiments have been described above, the present invention is not limited to these embodiments, and it is also possible to add other toner components into the resin coating layer.

[0061]

Effects of the Invention As described above, according to the toner manufacturing method of the present invention, by forming a colorant-containing resin coating layer using resin fine particles to which a colorant or the like is attached to the surface of the inner core particles, toner storage can be improved. Furthermore, since the colorant adhered to the toner surface does not come off, there is no contamination inside the device, and even though the amount of colorant is relatively small, the color is clear, especially if the colorant is anything other than black. When used, it has the outstanding effect of being able to form a highly transparent image and easily producing a toner with the property of not causing bleed-out with a small number of steps. Furthermore, regardless of the composition and structure of the inner core particles, the resin coating layer can be manufactured uniformly and easily by controlling the thickness.
This method has a great effect in that a multilayer structured toner having the above-mentioned excellent functions can be manufactured at a lower cost than conventional techniques.

Furthermore, the toner manufacturing method of the present invention and the toner obtained by the toner manufacturing method of the present invention can be used in image forming apparatuses using electrophotography, electrostatic recording, electrostatic printing, magnetic recording, etc.
In other words, it can be widely applied to copying machines, printers, facsimile machines, etc.

[Brief explanation of the drawing]

FIG. 1(a) is a diagram showing a flowchart of the toner manufacturing method of the present invention, and FIG. 1(b) is a schematic diagram of the toner obtained by the toner manufacturing method of the present invention.

[Explanation of symbols]

1 Binder resin 2. Resin fine particles 3 Coloring agent 4 Solvent 5 Inner core particle 6 Solvent dispersion 7 Adhesion treatment 8 Colorant-attached resin particles 9 External addition treatment 10　Resin fine particle external addition treatment inner core particles 11 Filming treatment 12 Resin coating layer 13 Colorant-containing resin-coated toner

Claims (2)

[Claims] Claim 1: A toner manufacturing method for forming a resin film layer using at least a colorant and fine resin particles on the surface of an inner core particle made of at least a binder resin, which is used in a dry development method, wherein at least a colorant is attached to the surface in advance. A method for producing a toner, comprising: adhering the fine resin particles to the surface of the inner core particles, and then treating the inner core particles with a solvent that dissolves the fine resin particles, thereby forming a resin coating layer containing at least a colorant. 2. Claim 1, wherein at least the coloring agent is attached to the surface of the resin fine particles by a wet method.
The toner manufacturing method described.