JP2013037206A - Toner, production method of the toner, developer using the toner, process cartridge and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a toner, which causes no filming on a contact member such as a developer carrier and a photoreceptor even in long-term use, can output an image with stabilized picture quality and is applicable to an image forming apparatus employing an electrophotographic system.SOLUTION: The toner comprises a binder resin, a colorant, wax and an external additive, and is obtained by depositing the external additive on toner base particles and then subjecting the particles to a mixing and stirring treatment with beads. The mixing and stirring treatment is carried out under the condition of a weight ratio (toner/beads) of the toner to beads of 0.35 or more and 0.75 or less. The beads have an average particle diameter of 3 mm or more and 20 mm or less and surface roughness Ra of 1 μm or more and 50 μm or less, and are wholly coated with a resin.

Description

  The present invention relates to a toner, a toner manufacturing method, a developer using the toner, a process cartridge, and an image forming apparatus.

In an image forming apparatus using an electrophotographic system, demands for higher image quality and energy saving are increasing. These demands are met by reducing the particle size of toner particles and improving fixability.
However, as the toner has a smaller particle size, the cohesiveness of the toner becomes stronger, thereby reducing the fluidity, and inorganic / organic fine particles imparting fluidity are externally added to supplement the transportability and mixing properties. In order to save energy, it is necessary to lower the fixing temperature of the toner, and a resin having a low softening temperature or a resin having a low viscosity upon melting is often used.

Inorganic particles externally added to the toner, the resin having a low softening temperature, and an aged product of a resin having a low viscosity at the time of melting are released from the toner due to stress with a member in contact with the toner, and the developer is supported. There is a problem that filming occurs because the toner adheres to a contact member such as a photosensitive member or a photosensitive member and becomes a starting point for toner to adhere.
This is a phenomenon in which the external additive previously attached to the toner particles, the wax contained in the toner, etc. migrates to the surface of the contact member such as the developer carrying member or the photosensitive member and adheres to the film. Along with this, image quality such as image blanking is adversely affected.

As a means for preventing such filming, a configuration for preventing filming has been studied from the electrostatic latent image carrier side. For example, Japanese Patent Application Laid-Open No. 2002-207397 of Patent Document 1 discloses an electrostatic latent image. It is disclosed that the upper limit of the surface friction coefficient of the image carrier is 0.5, and Japanese Patent Application Laid-Open No. 2000-330310 discloses a contact angle, hardness, and friction coefficient of the surface of the electrostatic latent image carrier. It is disclosed to define the surface roughness.

However, in these structures, filming cannot be sufficiently prevented when a toner having a low softening temperature or a resin having a low viscosity at the time of melting is used.
Further, in order to remove such filming, there is a means for improving the polishing function by a blade or the like, but in this case, the wear of the electrostatic latent image carrier increases, which is not preferable.

On the other hand, as for prevention of filming from the toner side, for example, Japanese Patent Application Laid-Open No. 7-311474 of Patent Document 3 discloses that the particle size distribution of the toner base and the physical property value of the additive are defined.
However, these methods cannot sufficiently prevent filming because the ease of filming varies depending on the surface state of the electrostatic latent image carrier.

In addition, as a method for removing the filming-causing substance contained in the toner, for example, in JP-A-7-271090 of Patent Document 4, the toner base is dispersed and sprayed in a hot air stream to melt the toner particle surface. And fixing the additive to the toner base particles.
Japanese Patent Application Laid-Open No. 2007-86812 of Patent Document 5 adds an external additive to coarsely pulverized developer main body particles, finely pulverizes and classifies the developer main body particles to which the external additive is added. Thus, it is disclosed that an external additive causing filming is fixed and a free external additive is removed.
Japanese Patent Application Laid-Open No. 2010-160234 of Patent Document 6 discloses that after toner base particles and silica are mixed, only the toner base particles are added and mixed, and the added toner base particles absorb free silica. It is disclosed.

However, the filming-causing substance is not only an external additive. In particular, in the case of pulverized toner, the pulverized toner is pulverized at the interface between the binder resin and the wax, and the wax is exposed on the toner surface.
Furthermore, in recent years, in order to realize particularly high-definition color image formation, a polymerization method produced by suspension polymerization, emulsion polymerization, dispersion polymerization, etc., for the purpose of reducing the toner particle size and spheroidizing. Many methods for producing toner particles by granulating toner particles in a liquid have been studied.
In the polymerization method, it is possible to obtain toner particles containing wax, but filming cannot be completely prevented even with a polymerized toner.

The reason for this is not clarified, but the toner is caused by the presence of fine powder such as toner fine powder, free additive of shell agent (resin fine particles) contained in the toner, and stress due to frictional charging in the developing device. The exudation of low melting point substances such as wax and unreacted monomer contained in the particles can be considered.

To provide a toner that can be applied to an electrophotographic image forming apparatus capable of outputting an image having a stable image quality without filming on a contact member such as a developer carrier or a photoreceptor even when used for a long time. To do.

The inventors of the present invention can effectively remove the filming-causing substances contained in the toner by mixing and stirring the toner to which the external additive is added and the resin-coated specific beads under a specific range of conditions. It has been found that filming on contact members such as a developer carrying member and a photosensitive member can be prevented over a period of time.
That is, the said subject is solved by following (1)-(6) of this invention.
(1) “A toner containing a binder resin, a colorant, a wax, and an external additive, which is obtained by adhering an external additive to the toner base particles and further mixing and stirring with beads. The mixing and stirring treatment is performed at a toner to bead weight ratio (toner / bead) of 0.35 to 0.75, and the beads have an average particle diameter of 3 mm to 20 mm and a surface roughness. Toner characterized in that Ra is 1 μm or more and 50 μm or less, and the entire surface is resin-coated ”
(2) “The toner according to item (1), wherein the toner has an external additive adhesion strength of 75% or more and 85% or less”,
(3) "The toner according to (1) or (2) above, wherein the beads have a specific gravity of 3.0 or more and 6.5 or less and a Vickers hardness of 10 or more",
(4) "The toner according to any one of (1) to (3) above, wherein the beads are urethane resin coated",
(5) “The toner according to any one of items (1) to (4), wherein the external additive includes inorganic fine particles having an average primary particle size of 10 nm to 50 nm” ,
(6) A “developer comprising the toner according to any one of (1) to (5)” and a carrier.

  As will be understood from the following detailed and specific description, a toner capable of outputting an image with stable image quality without filming on a contact member such as a developer carrying member and a photosensitive member even when used for a long period of time. Can be provided.

3 is a flowchart illustrating a toner manufacturing method. It is a figure which shows an example of the image forming apparatus of this invention. It is the schematic of a developing device. 1 is a schematic diagram of an image forming apparatus provided with a toner replenishing mechanism. It is a figure which shows an example of the process cartridge of this invention.

The toner of the present invention is a toner containing a binder resin, a colorant, a wax, and an external additive. After the external additive is attached to the toner base particles, the mixture is further stirred with specific beads under specific conditions. Is obtained.
By mixing the toner to which the external additive has adhered with specific beads coated with resin under specific conditions, the filming causative substance adheres to the surface of the beads, and the filming causative substance present in the toner particle surface and / or in the particles is removed. In addition to being able to be removed, the external additive can be firmly fixed to the base particles to prevent the occurrence of filming. In particular, in the case of pulverized toner, the degree of unevenness on the surface of the toner particles is alleviated and the fluidity is improved.

<Beads>
The beads have an average particle size of 3 mm to 20 mm, a surface roughness Ra of 1 μm to 50 μm, and are resin-coated.
If the average particle size of the beads is less than 3 mm, the toner particles are often cracked and chipped, and fine powder is likely to be generated. If the average particle size exceeds 20 mm, it is difficult to fix the external additive. Further, if the surface roughness Ra is 1 μm or less, the surface area of the beads is small and it is difficult to sufficiently remove the filming cause substance, and if it exceeds 50 μm, the ability to remove the filming cause substance is lowered.
The beads having Ra of 1 μm or more and 50 μm or less can be obtained by sandblasting or the like.

The resin is preferably the same type of resin as that on the surface of the developer carrying member. Here, the resin of the same type as the resin on the surface of the developer carrying member only needs to have the same structure in the repeating unit, and the side chain portion, the copolymerization component, and the like may be different. Since the surface of the developer carrying member is often a urethane resin, it is preferably coated with urethane. For example, isocyanates such as tolylene diisocyanate and hexamethylene diisocyanate, xylylene diisocyanate, and urethane polyols are used. The resin coating can be performed by a known method such as a spray method or a dipping method.
The resin layer of the bead coats the entire surface of the bead uniformly, and the film thickness is preferably 0.1 μm or more and 50 μm or less. If it is less than 0.1 μm, the filming-causing substance cannot be sufficiently removed, and if it exceeds 50 μm, it is difficult to fix the external additive.

The bead core preferably has a specific gravity of 3.0 or more and 6.5 or less and a Vickers hardness of 10 or more and 20 or less. If the specific gravity is less than 3.0, it is too light to fix the external additive, and if it exceeds 6.5, it is too heavy and the toner particles may be cracked or chipped. If the Vickers hardness is less than 10, the durability is inferior.
Examples of such a bead core material include alumina, zirconia, silicon nitride, silicon carbide and the like, and alumina is preferable.

<Bead mixing process>
The mixing process is performed until the external additive adhesion strength is 75% or more and 85% or less. If the external additive adhesion strength is less than 75%, there are many free external additives and filming cannot be sufficiently prevented. If it exceeds 85%, the external additive is buried in the toner particles, and the fluidity imparting effect is lowered. is there.
The external additive adhesion strength can be adjusted by the rotational speed, mixing time, and the like.
The mixing process is performed at a toner / bead weight ratio (toner / bead) of 0.35 to 0.75. If it is less than 0.35, the external additive is not sufficiently fixed, and if it exceeds 0.75, the toner is cracked or chipped.
Moreover, as a mixing processing apparatus, mixing apparatuses, such as a ball mill and a V-type mixer, can be used.

Next, the toner will be described.
The toner of the present invention contains a binder resin, a colorant, a wax and an external additive, and may be a so-called pulverized toner or polymerized toner.
First, the pulverized toner will be described.

(Binder resin)
The type of the binder resin is not particularly limited, and is known in the toner field, for example, a polyester resin, a (meth) acrylic resin, a styrene- (meth) acrylic copolymer resin, an epoxy resin, Although it may be COC (cyclic olefin resin (for example, TOPAS-COC (manufactured by Ticona))) or the like, it is preferable to use a polyester resin from the viewpoint of oilless fixing.

As the polyester resin preferably used in the present invention, a polyester resin obtained by polycondensation of a polyhydric alcohol component and a polyvalent carboxylic acid component can be used.
Among the polyhydric alcohol components, examples of the dihydric alcohol component include polyoxypropylene (2,2) -2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene (3,3) -2,2- Bis (4-hydroxyphenyl) propane, polyoxypropylene (6) -2,2-bis (4-hydroxyphenyl) propane, polyoxyethylene (2,0) -2,2-bis (4-hydroxyphenyl) propane Bisphenol A alkylene oxide adducts such as ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, neopentyl glycol, 1,4-butenediol, 1,5-pentanediol, 1,6-hexanedio , 1,4-cyclohexanedimethanol, dipropylene glycol, polyethylene glycol, polytetramethylene glycol, bisphenol A, hydrogenated bisphenol A, and the like.
Examples of the trivalent or higher alcohol component include sorbitol, 1,2,3,6-hexanetetrol, 1,4-sorbitan, pentaerythritol, dipentaerythritol, tripentaerythritol, 1,2,4-butanetriol. 1,2,5-pentanetriol, glycerol, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane, 1,3,5-trihydroxymethylbenzene, etc. Is mentioned.

Among the polyvalent carboxylic acid components, examples of the divalent carboxylic acid component include maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, phthalic acid, isophthalic acid, terephthalic acid, cyclohexanedicarboxylic acid, and succinic acid. , Adipic acid, sebacic acid, azelaic acid, malonic acid, n-dodecenyl succinic acid, isododecenyl succinic acid, n-dodecyl succinic acid, isododecyl succinic acid, n-octenyl succinic acid, isooctenyl succinic acid, n-octyl succinic acid , Isooctyl succinic acid, anhydrides or lower alkyl esters of these acids.
Examples of the trivalent or higher carboxylic acid component include 1,2,4-benzenetricarboxylic acid (trimellitic acid), 1,2,5-benzenetricarboxylic acid, 2,5,7-naphthalenetricarboxylic acid, 1,2 , 4-Naphthalenetricarboxylic acid, 1,2,4-butanetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, 1,3-dicarboxyl-2-methyl-2-methylenecarboxypropane, 1,2,4- Examples include cyclohexanetricarboxylic acid, tetra (methylenecarboxyl) methane, 1,2,7,8-octanetetracarboxylic acid, pyromellitic acid, empole trimer acid, anhydrides of these acids, and lower alkyl esters.

  In the present invention, as a polyester resin, a polyester resin raw material monomer, a vinyl resin raw material monomer, and a mixture of monomers that react with both resin raw material monomers are used to obtain a polyester resin in the same container. A resin obtained by performing a condensation polymerization reaction and a radical polymerization reaction for obtaining a vinyl resin in parallel (hereinafter, simply referred to as “vinyl polyester resin”) can also be suitably used. In addition, the monomer which reacts with the raw material monomers of both resins is, in other words, a monomer that can be used for both the condensation polymerization reaction and the radical polymerization reaction. That is, it is a monomer having a carboxy group that can undergo a condensation polymerization reaction and a vinyl group that can undergo a radical polymerization reaction, and examples thereof include fumaric acid, maleic acid, acrylic acid, and methacrylic acid.

  Examples of the raw material monomer for the polyester resin include the aforementioned polyhydric alcohol component and polyvalent carboxylic acid component. Examples of the raw material monomer for the vinyl resin include styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, α-methylstyrene, p-ethylstyrene, 2,4-dimethylstyrene, p-tert- Styrene or styrene derivatives such as butylstyrene and p-chlorostyrene; Ethylene unsaturated monoolefins such as ethylene, propylene, butylene and isobutylene; methyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate , Isobutyl methacrylate, t-butyl methacrylate, n-pentyl methacrylate, isopentyl methacrylate, neopentyl methacrylate, 3- (methyl) butyl methacrylate, hexyl methacrylate, octyl methacrylate, nonyl methacrylate Methacrylic acid alkyl esters such as decyl methacrylate, undecyl methacrylate, dodecyl methacrylate; methyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, t-butyl acrylate, acrylic Alkyl acrylates such as n-pentyl acid, isopentyl acrylate, neopentyl acrylate, 3- (methyl) butyl acrylate, hexyl acrylate, octyl acrylate, nonyl acrylate, decyl acrylate, undecyl acrylate, and dodecyl acrylate Esters; unsaturated carboxylic acids such as acrylic acid, methacrylic acid, itaconic acid, maleic acid; acrylonitrile, maleic acid ester, itaconic acid ester, vinyl chloride, vinyl acetate, vinyl benzoate, vinylmethyl Examples include ethyl ketone, vinyl hexyl ketone, vinyl methyl ether, vinyl ethyl ether, and vinyl isobutyl ether.

As a polymerization initiator when polymerizing the raw material monomer of the vinyl resin, for example, 2,2′-azobis (2,4-dimethylvaleronitrile), 2,2′-azobisisobutyronitrile, 1,1 Azo or diazo polymerization initiators such as' -azobis (cyclohexane-1-carbonitrile), 2,2'-azobis-4-methoxy-2,4-dimethylvaleronitrile, benzoyl peroxide, dicumyl peroxide, And peroxide polymerization initiators such as methyl ethyl ketone peroxide, isopropyl peroxycarbonate, lauroyl peroxide, and the like.

A single binder resin may be used, or two kinds of low molecular weight substances and high molecular weight substances, or a combination of plural kinds thereof may be used. From the viewpoint of further improving the offset resistance, it is more preferable to use at least one low molecular weight substance and high molecular weight substance.
A more preferable resin is a polyester resin obtained by polycondensation of the above-described polyhydric alcohol component and polyhydric carboxylic acid component, and in particular, a bisphenol A alkylene oxide adduct is used as the polyhydric alcohol component, and terephthalate is used as the polyhydric carboxylic acid component. It is a polyester resin obtained using acid and fumaric acid.

  In addition, the high molecular weight material is a vinyl polyester resin, in particular, bisphenol A alkylene oxide adduct, terephthalic acid, trimellitic acid and succinic acid are used as raw material monomers for polyester resin, and styrene and butyl acrylate are used as raw material monomers for vinyl resin. It is also possible to use a vinyl-based polyester resin obtained using fumaric acid as a bireactive monomer.

(Release agent)
Although it does not specifically limit as a mold release agent of this invention, A hydrocarbon paraffin is mentioned.
Examples of hydrocarbon paraffin include low molecular weight polyalkene obtained by polymerizing alkenes under high pressure using radical polymerization or low pressure using Ziegler catalyst; polyalkene obtained by thermally decomposing high molecular weight polyalkene; carbon monoxide and hydrogen And hydrocarbons obtained by synthesizing a synthesis gas using the age method, and hydrocarbons obtained by hydrogenation. By using such a release agent, the release agent sufficiently oozes out from the developer during fixing, and excellent fixing characteristics can be exhibited.

  As a method for adding to the toner, in addition to adding at the time of toner production, it may be added at the time of synthesizing the binder resin. In this case, when using the above-mentioned polyester resin as a binder resin, it is preferable to use a hydrocarbon-based release agent. In order to add the hydrocarbon-based release agent to the binder resin in advance, when synthesizing the binder resin, the hydrocarbon-based release agent is added in the monomer for synthesizing the binder resin. A synthetic resin may be synthesized. For example, the polycondensation reaction may be performed in a state in which a hydrocarbon-based release agent is added to an acid monomer and an alcohol monomer constituting a polyester resin as a binder resin. When the binder resin is a vinyl-based polyester resin, with the hydrocarbon-based release agent added to the polyester resin raw material monomer, the vinyl resin raw material monomer is added dropwise to the monomer while stirring and heating the monomer. Then, a polycondensation reaction and a radical polymerization reaction may be performed.

(Release agent dispersant)
The toner of the present invention may contain a release agent dispersant that helps disperse the release agent. There is no particular limitation on the release agent dispersant, and a known one can be used, and a polymer or oligomer in which a highly compatible unit with the release agent and a highly compatible unit with the resin exist as a block body. Polymers or oligomers that are grafted on one of the highly compatible units with the release agent and the resin, and unsaturated carbonization such as ethylene, propylene, butene, styrene, α-styrene Copolymers of hydrogen and α, β-unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, maleic anhydride, itaconic acid, itaconic anhydride, their esters or their anhydrides, vinyl resins and polyesters And a block or graft body.
Examples of the unit having high compatibility with the release agent include long chain alkyl groups having 12 or more carbon atoms, polyethylene, polypropylene, polybutene, polybutadiene and copolymers thereof, and high compatibility with the resin. Examples of the unit include polyester and vinyl resin.

(Charge control agent)
Known charge control agents for controlling the charge amount of the toner particles can be used. For example, nigrosine dyes, triphenylmethane dyes, chromium-containing metal complex dyes, molybdate chelate pigments, rhodamine dyes, alkoxy amines, Quaternary ammonium salts (including fluorine-modified quaternary ammonium salts), alkylamides, phosphorus simple substances or compounds, tungsten simple substances or compounds, fluorine-based activators, salicylic acid metal salts, and metal salts of salicylic acid derivatives. Specifically, Bontron 03 of a nigrosine dye, Bontron P-51 of a quaternary ammonium salt, Bontron S-34 of a metal-containing azo dye, E-82 of an oxynaphthoic acid metal complex, E-84 of a salicylic acid metal complex , Phenolic condensate E-89 (above, Orient Chemical Industries, Ltd.), quaternary ammonium salt molybdenum complex TP-302, TP-415 (above, Hodogaya Chemical Co., Ltd.), quaternary ammonium salt copy Charge PSY VP2038, copy blue PR of triphenylmethane derivative, copy charge of quaternary ammonium salt NEG VP2036, copy charge NX VP434 (manufactured by Hoechst), LRA-901, LR-147 which is a boron complex (Nippon Carlit) Manufactured), copper phthalocyanine, perylene, quinacridone, azo series Fee, a sulfonic acid group, a carboxyl group, and polymer compounds having a functional group such as quaternary ammonium salts. Of these, substances that control the negative polarity of the toner are particularly preferably used.
The amount of charge control agent used is determined by the toner production method including the type of binder resin, the presence or absence of additives used as necessary, and the dispersion method, and is not limited uniquely. However, it is normally used in the range of 0.1 to 10 parts by mass with respect to 100 parts by mass of the binder resin. Preferably, the range of 0.2-5 mass parts is good. When the amount exceeds 10 parts by mass, the chargeability of the toner is too high, the effect of the charge control agent is reduced, the electrostatic attractive force with the developing roller is increased, the developer fluidity is lowered, and the image density is lowered. May be invited.

(Coloring agent)
As the colorant, the following known ones can be used. Carbon black, Nigrosine dye, Iron black, Naphthol yellow S, Hansa yellow (10G, 5G, G), Cadmium yellow, Yellow iron oxide, Ocher, Yellow lead, Titanium yellow, Polyazo yellow, Oil yellow, Hansa yellow ( GR, A, RN, R), Pigment Yellow L, Benzidine Yellow (G, GR), Permanent Yellow (NCG), Vulcan Fast Yellow (5G, R), Tartrazine Lake, Quinoline Yellow Lake, Anthrazan Yellow BGL, Iso Indolinone Yellow, Bengala, Pangtan, Pepper Red, Cadmium Red, Cadmium Mercury Red, Antimony Zhu, Permanent Red 4R, Para Red, Faise Red, Parachlor Ortho Nitroaniline Red, Resol Fast Scarlet G, Brillia Fast Scarlet, Brilliant Carmine BS, Permanent Red (F2R, F4R, FRL, FRLL, F4RH), Fast Scarlet VD, Belkan Fast Rubin B, Brilliant Scarlet G, Resol Rubin GX, Permanent Red F5R, Brilliant Carmine 6B, Pigment Scarlet 3B Bordeaux 5B, Toluidine Maroon, Permanent Bordeaux F2K, Helio Bordeaux BL, Bordeaux 10B, Bon Maroon Light, Bon Maroon Medium, Eosin Lake, Rhodamine Lake B, Rhodamine Lake Y, Alizarin Lake, Thioindigo Red B, Thioindigo Maroon, Oil red, quinacridone red, pyrazolone red, polyazo red, chrome vermilion, benzidine orange Perinone Orange, Oil Orange, Cobalt Blue, Cerulean Blue, Alkaline Blue Lake, Peacock Blue Lake, Victoria Blue Lake, Metal Free Phthalocyanine Blue, Phthalocyanine Blue, Fast Sky Blue, Indanthrene Blue (RS, BC), Indigo, Ultramarine Blue , Bitumen, anthraquinone blue, fast violet B, methyl violet lake, cobalt purple, manganese purple, dioxane violet, anthraquinone violet, chrome green, zinc green, chromium oxide, pyridian, emerald green, pigment green B, naphthol green B, green gold , Acid green lake, malachite green lake, phthalocyanine green, anthraquinone green, titanium oxide, sub Lead flower, lithopone and mixtures thereof can be used.
The content of the colorant is usually 1 to 15% by mass, preferably 3 to 10% by mass with respect to the toner.

(Colorant masterbatch)
The colorant used in the present invention may be a master batch combined with a resin.
As the binder resin kneaded together with the production of the master batch or the master batch, in addition to the above-mentioned polyester and vinyl resins, rosin, modified rosin, terpene resin, aliphatic or alicyclic hydrocarbon resin, Aromatic petroleum resins, chlorinated paraffins, paraffin release agents and the like can be mentioned, and these can be used alone or in combination.

<Polymerized toner>
[Toner Production Method]
As a method for producing the polymerized toner, a suspension polymerization method, an emulsion polymerization method, a dispersion polymerization method, and the like can be used. The ester elongation method will be described as an example.
In the ester elongation method, at least a polyester resin, a polymer having a site capable of reacting with a compound having an active hydrogen group, a colorant and a release agent are dissolved or dispersed in an organic solvent, and then the dissolved or dispersed material is dissolved. At least a step of dispersing and granulating in an aqueous medium is included.
More specifically, it is as follows.

[Granulation process]
(Organic solvent)
As an organic solvent for dissolving or dispersing a polyester resin, a polymer having a site capable of reacting with a compound having an active hydrogen group, a colorant and a release agent, “POLYMER HANDBOOK” 4th Edition, WILEY-INTERSCIENCE Volume 2, Section A Hansen solubility parameter described in VII is preferably 19.5 or less, and volatile with a boiling point of less than 100 ° C. is preferable from the viewpoint of easy removal of the solvent later.
Examples of such organic solvents include toluene, xylene, benzene, carbon tetrachloride, methylene chloride, 1,2-dichloroethane, 1,1,2-trichloroethane, trichloroethylene, chloroform, monochlorobenzene, dichloroethylidene, methyl acetate, Ethyl acetate, methyl ethyl ketone, methyl isobutyl ketone and the like can be used alone or in combination of two or more. Particularly preferred are ester solvents such as methyl acetate and ethyl acetate, aromatic solvents such as toluene and xylene, and halogenated hydrocarbons such as methylene chloride, 1,2-dichloroethane, chloroform and carbon tetrachloride.
The polyester resin, the colorant and the release agent may be dissolved or dispersed at the same time. Usually, each of them is dissolved or dispersed alone, and the organic solvents used at that time may be different or the same. It is preferable that the same is taken into consideration.

(Dissolution or dispersion of polyester resin)
The dissolved or dispersed polyester resin preferably has a resin concentration of about 40% to 80%. If the concentration is too high, it will be difficult to dissolve or disperse, and the viscosity will be too high to handle. On the other hand, if the density is too low, the amount of toner produced decreases.
When a modified polyester resin having an isocyanate group at the terminal is mixed with a binder resin having an aromatic group-containing polyester skeleton, it may be mixed in the same solution or dispersion, or separately prepared in a solution or dispersion. However, considering the respective solubility and viscosity, it is preferable to prepare separate solutions or dispersions.

(Dissolution or dispersion of colorant)
The colorant may be dissolved or dispersed alone, or may be mixed in the solution or dispersion of the polyester resin. If necessary, a dispersion aid or a polyester resin may be added, or the master batch may be used.

(Dissolution or dispersion of release agent)
When dissolving or dispersing wax as a release agent, when using an organic solvent in which wax does not dissolve, it is used as a dispersion, but the dispersion is prepared by a general method. That is, an organic solvent and wax may be mixed and dispersed with a disperser such as a bead mill. Further, after mixing the organic solvent and the wax, it is sometimes possible to shorten the dispersion time by once heating to the melting point of the wax, cooling with stirring and then dispersing with a disperser such as a bead mill.
In addition, a plurality of waxes may be mixed and used, or a dispersion aid or a polyester resin may be added.

(Aqueous medium)
As an aqueous medium to be used, water alone may be used, but a solvent miscible with water may be used in combination. Furthermore, an organic solvent having a Hansen solubility parameter of 19.5 or less used in the oil phase may be mixed, and preferably the addition amount in the vicinity of the saturation amount with respect to water increases the emulsification or dispersion stability of the oil phase. it can. Examples of the miscible solvent include alcohol (methanol, isopropanol, ethylene glycol, etc.), dimethylformamide, tetrahydrofuran, cellosolves (methylcellosolve, etc.), lower ketones (acetone, methyl ethyl ketone, etc.) and the like.
The amount of the aqueous medium used relative to 100 parts by mass of the toner composition is usually 50 to 2000 parts by mass, preferably 100 to 1000 parts by mass. If the amount is less than 50 parts by mass, the dispersion state of the toner composition is poor and toner particles having a predetermined particle diameter cannot be obtained. Moreover, when it exceeds 2000 mass parts, it is not economical.

(Inorganic dispersant and organic resin fine particles)
When the dissolved or dispersed toner composition is dispersed in the aqueous medium, by dispersing the inorganic dispersant or the organic resin fine particles in the aqueous medium in advance, the particle size distribution is sharpened and the dispersion is reduced. It is preferable in terms of stability. As the inorganic dispersant, tricalcium phosphate, calcium carbonate, titanium oxide, colloidal silica, hydroxyapatite and the like are used. As the resin forming the organic resin fine particles, any resin can be used as long as it can form an aqueous dispersion, and it may be a thermoplastic resin or a thermosetting resin. Includes vinyl resins, polyurethane resins, epoxy resins, polyester resins, polyamide resins, polyimide resins, silicon resins, phenol resins, melamine resins, urea resins, aniline resins, ionomer resins, polycarbonate resins, and the like. These resins may be used in combination of two or more. Of these, vinyl resins, polyurethane resins, epoxy resins, polyester resins, and combinations thereof are preferable from the viewpoint that an aqueous dispersion of fine spherical resin particles is easily obtained.

(Method for dispersing organic resin fine particles in water)
The method of making the resin into an aqueous dispersion of fine organic resin particles is not particularly limited, and examples thereof include the following (a) to (h).
(A) In the case of a vinyl resin, a method of directly producing an aqueous dispersion of resin fine particles by a polymerization reaction such as a suspension polymerization method, an emulsion polymerization method, a seed polymerization method or a dispersion polymerization method using a monomer as a starting material .
(B) In the case of polyaddition or condensation resin such as polyester resin, polyurethane resin, epoxy resin, etc., a precursor (monomer, oligomer, etc.) or a solvent solution thereof is dispersed in an aqueous medium in the presence of a suitable dispersant, A method of producing an aqueous dispersion of resin fine particles by heating and then adding a curing agent to cure.
(C) In the case of polyaddition or condensation resin such as polyester resin, polyurethane resin, and epoxy resin, a precursor (monomer, oligomer, etc.) or a solvent solution thereof (preferably liquid) may be liquefied by heating. .) A method in which a suitable emulsifier is dissolved therein, and then water is added to perform phase inversion emulsification.
(D) A resin prepared in advance by a polymerization reaction (any polymerization reaction mode such as addition polymerization, ring-opening polymerization, polyaddition, addition condensation, condensation polymerization, etc.) can be used as a mechanical rotary type or jet type resin. A method in which resin fine particles are obtained by pulverization using a fine pulverizer and then classification, and then dispersed in water in the presence of an appropriate dispersant.
(E) A resin solution obtained by dissolving a resin prepared in advance by a polymerization reaction (any polymerization reaction mode such as addition polymerization, ring-opening polymerization, polyaddition, addition condensation, condensation polymerization, etc.) in a solvent, A method in which resin fine particles are obtained by spraying in the form of a mist and then dispersed in water in the presence of an appropriate dispersant.
(F) A solvent is added to a resin solution obtained by dissolving a resin prepared in advance by a polymerization reaction (any polymerization reaction mode such as addition polymerization, ring-opening polymerization, polyaddition, addition condensation, condensation polymerization, etc.) in a solvent. The resin fine particles are precipitated by cooling the resin solution previously dissolved in a solvent by heating, and then the solvent is removed to obtain resin fine particles, which are then dispersed in water in the presence of a suitable dispersant. Method.
(G) A resin solution obtained by dissolving a resin prepared in advance by a polymerization reaction (any polymerization reaction mode such as addition polymerization, ring-opening polymerization, polyaddition, addition condensation, condensation polymerization, etc.) in a solvent, A method of dispersing in an aqueous medium in the presence of an appropriate dispersant and removing the solvent by heating or decompression.
(H) In a resin solution in which a resin prepared in advance by a polymerization reaction (any polymerization reaction mode such as addition polymerization, ring-opening polymerization, polyaddition, addition condensation, condensation polymerization, etc.) is dissolved in a solvent. A method of phase inversion emulsification by adding water after dissolving an appropriate emulsifier.

(Surfactant)
Further, a surfactant or the like can be used as necessary in order to emulsify and disperse the oily phase containing the toner composition in the aqueous medium. As surfactants, anionic surfactants such as alkylbenzene sulfonates, α-olefin sulfonates, phosphate esters, alkylamine salts, amino alcohol fatty acid derivatives, polyamine fatty acid derivatives, amine salt types such as imidazoline, Quaternary ammonium salt type cationic surfactants such as alkyltrimethylammonium salt, dialkyldimethylammonium salt, alkyldimethylbenzylammonium salt, pyridinium salt, alkylisoquinolinium salt, benzethonium chloride, fatty acid amide derivative, polyhydric alcohol Nonionic surfactants such as derivatives, for example, amphoteric surfactants such as alanine, dodecyldi (aminoethyl) glycine, di (octylaminoethyl) glycine and N-alkyl-N, N-dimethylammonium betaine. It is.
Further, by using a surfactant having a fluoroalkyl group, the effect can be obtained in a very small amount. Examples of the anionic surfactant having a fluoroalkyl group preferably used include fluoroalkylcarboxylic acids having 2 to 10 carbon atoms, and metal salts thereof, disodium perfluorooctanesulfonyl glutamate, 3- [ω-fluoroalkyl (C6 -C11) Oxy] -1-alkyl (C3-C4) sodium sulfonate, 3- [ω-fluoroalkanoyl (C6-C8) -N-ethylamino] -1-propanesulfonic acid sodium, fluoroalkyl (C11-C20) ) Carboxylic acid and its metal salt, Perfluoroalkylcarboxylic acid (C7 to C13) and its metal salt, Perfluoroalkyl (C4 to C12) sulfonic acid and its metal salt, Perfluorooctanesulfonic acid diethanolamide, N-propyl- N- (2-hydroxyethyl) Perfluorooctanesulfonamide, perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salt, perfluoroalkyl (C6-C10) -N-ethylsulfonylglycine salt, monoperfluoroalkyl (C6-C16) ethyl phosphate, etc. Is mentioned. In addition, examples of the cationic surfactant include aliphatic quaternary ammonium salts such as aliphatic primary, secondary or secondary amine acids having a fluoroalkyl group, and perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salts. Benzalkonium salt, benzethonium chloride, pyridinium salt, imidazolinium salt and the like.

(Protective colloid)
Further, the dispersed droplets may be stabilized by a polymer protective colloid. For example, acrylic acid, methacrylic acid, α-cyanoacrylic acid, α-cyanomethacrylic acid, itaconic acid, crotonic acid, fumaric acid, maleic acid or maleic anhydride and other (meth) acrylic monomer Bodies such as β-hydroxyethyl acrylate, β-hydroxyethyl methacrylate, β-hydroxypropyl acrylate, β-hydroxypropyl methacrylate, γ-hydroxypropyl acrylate, γ-hydroxypropyl methacrylate, 3-acrylate Chloro-2-hydroxypropyl, 3-chloro-2-hydroxypropyl methacrylate, diethylene glycol monoacrylate, diethylene glycol monomethacrylate, glycerol monoacrylate, glycerol monomethacrylate, N -Of methyl alcohol acrylamide, N-methylol methacrylamide, etc., vinyl alcohol or ethers with vinyl alcohol, such as vinyl methyl ether, vinyl ethyl ether, vinyl propyl ether, or compounds containing vinyl alcohol and carboxyl group Esters such as vinyl acetate, vinyl propionate, vinyl butyrate, acrylamide, methacrylamide, diacetone acrylamide or their methylol compounds, acid chlorides such as acrylic acid chloride, methacrylic acid chloride, vinyl pyridine, vinyl pyrrolidone, vinyl imidazole , Homopolymers or copolymers such as those having a nitrogen atom such as ethyleneimine or its heterocyclic ring, polyoxyethylene, polyoxypropylene, Oxyethylene alkylamine, polyoxypropylene alkylamine, polyoxyethylene alkylamide, polyoxypropylene alkylamide, polyoxyethylene nonyl phenyl ether, polyoxyethylene lauryl phenyl ether, polyoxyethylene stearyl phenyl ester, polyoxyethylene nonylphenyl Polyoxyethylenes such as esters, celluloses such as methyl cellulose, hydroxyethyl cellulose, and hydroxypropyl cellulose can be used.
In addition, when an acid such as calcium phosphate salt or an alkali-soluble substance is used as the dispersion stabilizer, the calcium phosphate salt is removed from the fine particles by a method such as dissolving the calcium phosphate salt with an acid such as hydrochloric acid and washing with water. To do. It can also be removed by operations such as enzymatic degradation. When a dispersant is used, the dispersant can remain on the surface of the toner particles, but it is preferable to remove it by washing from the charged surface of the toner.

(Distribution method)
The dispersion method is not particularly limited, and known equipment such as a low-speed shear method, a high-speed shear method, a friction method, a high-pressure jet method, and an ultrasonic wave can be applied. In order to make the particle size of the dispersion 2 to 20 μm, a high-speed shearing type is preferable. When a high-speed shearing disperser is used, the rotational speed is not particularly limited, but is usually 1000 to 30000 rpm, preferably 5000 to 20000 rpm. The temperature during dispersion is usually 0 to 150 ° C. (under pressure), preferably 20 to 80 ° C.

(Desolation)
In order to remove the organic solvent from the obtained emulsified dispersion, a known method can be used. For example, a method can be employed in which the entire system is gradually heated under normal pressure or reduced pressure to completely evaporate and remove the organic solvent in the droplets.

<Extension or / and cross-linking reaction>
For the purpose of introducing a urea-modified polyester resin, when a modified polyester resin having an isocyanate group at the terminal and an amine capable of reacting with it are added, the amine is added in the oil phase before the toner composition is dispersed in an aqueous medium. In addition, amines may be added to the aqueous medium. The time required for the above reaction is selected depending on the reactivity between the isocyanate group structure of the polyester prepolymer and the added amines, but is usually 1 minute to 40 hours, preferably 1 to 24 hours. The reaction temperature is usually 0 to 150 ° C., preferably 20 to 98 ° C. This reaction may be performed before the fine particle adhesion step, or may be performed simultaneously during the fine particle adhesion step. Further, it may be after the fine particle adhesion step is completed. Moreover, a well-known catalyst can be used as needed.

[Washing and drying process]
A known technique is used for washing and drying the toner particles dispersed in the aqueous medium.
That is, after solid-liquid separation with a centrifuge, a filter press, etc., the obtained toner cake is redispersed in ion exchange water at about room temperature to about 40 ° C., and after adjusting the pH with acid or alkali as necessary, After removing the impurities and surfactants by repeating the process of solid-liquid separation again and again, the toner powder is obtained by drying with an air dryer, circulating dryer, vacuum dryer, vibration fluid dryer, etc. . At this time, the fine particle component of the toner may be removed by centrifugation or the like, and a desired particle size distribution can be obtained using a known classifier after drying, if necessary.
A toner can be obtained by performing the following treatment on the colored particles obtained by the above pulverization method and ester elongation method.

[Heat treatment]
The heat treatment step is preferably performed in the above-described washing and drying step, and when the toner particles after the solid-liquid separation at least once are redispersed, it is desirable to heat to a temperature equal to or higher than the glass transition temperature of the toner. A surfactant may be added in order to disperse the toner during the heat treatment.
When heat treatment is performed after the drying step, it is particularly preferable to add a surfactant to the medium in order to sufficiently disperse the toner in an aqueous system.
By this treatment, the low molecular weight component exposed on the toner surface is melted and released into the aqueous medium. The heating temperature may be equal to or higher than the glass transition temperature of the toner. However, if the heating temperature is too high, the toners may agglomerate with each other. The heating time is preferably 1 hour to 24 hours, and particularly preferably 8 hours to 16 hours. When the heating time is short, the low molecular weight component is not sufficiently melted, and since the melting amount of the low molecular weight component is almost saturated when the heating time is 24 hours, it is not necessary to heat for 24 hours or more.
Thereafter, washing and solid-liquid separation are performed as necessary, and finally dried to obtain toner particles.

[External processing]
The obtained toner powder is mixed with different particles such as charge control fine particles and fluidizing agent fine particles so that the particles are fixed and fused on the surface, and the particles of the resulting composite particles are detached from the surface. Can be prevented. Specific means include a method of applying an impact force to the mixture by blades rotating at high speed, a method of injecting and accelerating the mixture in a high-speed air stream, and causing particles or composite particles to collide with an appropriate collision plate, etc. is there. Examples of the apparatus include a Henschel mixer (manufactured by Mitsui Mining) and a super mixer (manufactured by Kawata).

(External additive)
In the present invention, one or more inorganic fine particles are preferably used as an external additive for assisting the fluidity and chargeability / developability / transferability of toner particles. The BET specific surface area of the inorganic fine particles is ^preferably from ^{30m 2 / g~300m 2 / g,} 10nm~50nm preferably as the primary particle diameter.
Specific examples of the inorganic fine particles include, for example, silicon oxide, zinc oxide, tin oxide, silica sand, titanium oxide, clay, mica, wollastonite, diatomaceous earth, chromium oxide, cerium oxide, bengara, antimony trioxide, magnesium oxide, Examples thereof include aluminum oxide, zirconium oxide, barium sulfate, barium carbonate, calcium carbonate, silicon carbide, and silicon nitride.
When the primary particle diameter of the external additive is 10 nm or less, the embedding of the external additive in the toner is deteriorated, the image quality deterioration fluctuation is increased, and the durability is deteriorated. When the primary additive has a primary particle diameter of 50 nm or more, the external additive is detached from the toner, and filming occurs on the photoreceptor.

(Developer)
As described above, the toner of the present invention can be used as a one-component developer or a two-component developer. When the toner having the base particles of the present invention is used for a two-component developer, it may be used by mixing with a magnetic carrier, and the content ratio of the carrier and the toner in the developer is 100 parts by weight of the carrier. 1 to 10 parts by weight is preferred.
As the magnetic carrier, conventionally known ones such as iron powder, ferrite powder, magnetite powder, magnetic resin carrier having a particle diameter of about 20 to 200 μm can be used.
Examples of the coating material for the magnetic carrier include amino resins such as urea-formaldehyde resin, melamine resin, benzoguanamine resin, urea resin, polyamide resin, and epoxy resin. Polyvinyl and polyvinylidene resins, for example, acrylic resins, polymethyl methacrylate resins, polyacrylonitrile resins, polyvinyl acetate resins, polyvinyl alcohol resins, polyvinyl butyral resins, polystyrene resins and styrene acrylic copolymer resins, and other polystyrene resins, Halogenated olefin resins such as polyvinyl chloride, polyester resins such as polyethylene terephthalate resin and polybutylene terephthalate resin, polycarbonate resins, polyethylene resins, polyvinyl fluoride resins, polyvinylidene fluoride resins, polytrifluoroethylene resins, poly Hexafluoropropylene resin, copolymer of vinylidene fluoride and acrylic monomer, copolymer of vinylidene fluoride and vinyl fluoride, tetrafluoroethylene and vinyl fluoride Den and non-fluoride monomers including a fluoro such as terpolymers of, and silicone resins.
Moreover, you may contain electrically conductive powder etc. in coating resin as needed. As the conductive powder, metal powder, carbon black, titanium oxide, tin oxide, zinc oxide or the like can be used. These conductive powders preferably have an average particle diameter of 1 μm or less. When the average particle diameter is larger than 1 μm, it becomes difficult to control electric resistance.

The toner of the present invention is implemented by, for example, an image forming apparatus using an electrophotographic process as shown in the schematic configuration diagram of FIG. Hereinafter, a schematic configuration of the image forming apparatus illustrated in FIG. 2 will be described.
The latent image carrier (1) is charged by the charging device (2), and a latent image is written on the latent image carrier (1). A bias is applied to the developing roller (40) and the latent image carrier (1), and the written latent image is supplied by the supply roller (41) and is regulated by the regulating blade (43) on the developing roller (40). It is developed and visualized in accordance with the latent image at the contact portion with the thinned developer (44). The developer (44) visualized and developed on the latent image is temporarily transferred to the intermediate transfer material (8), transferred to a recording medium (9) such as paper, and fixed on the recording medium (9) by a fixing device. Is done. On the other hand, a small amount of developer on the latent image remains on the latent image carrier after passing through the intermediate transfer material. This developer is collected and discarded by a blade-like cleaning member (7).

The developing unit of the image forming apparatus will be described below.
FIG. 3 is a schematic view of the developing device (process cartridge). The developer (toner) (44) in the toner replenishing portion inside the container is carried to the nip portion of the developing roller (40) while being stirred by the supply roller (41). Further, the toner amount on the developing roller is regulated by the regulating blade (43), and a thin toner layer on the developing roller is formed. In addition, the toner is rubbed between the nip portion of the supply roller and the developing roller, the regulating member, and the developing roller, and is controlled to an appropriate charge amount.
In particular, in the cleanerless process, the transfer toner is collected, so that the chargeability greatly deviates from an appropriate value. Therefore, the toner collected by the developing roller must be sufficiently scraped and removed by the supply roller.

In the present invention, a developing device that replenishes toner may be used. For example, a toner replenishing mechanism may be attached to the upper portion of the toner replenishing portion in FIG.
FIG. 4 is a schematic view of a developing device of a toner replenishment type. It is preferable that the toner container (031) is connected to the developing device, and the toner replenishing container is always stirred with a stirring paddle (030) or the like in order to maintain the fluidity of the toner. In the toner container, conveying means such as a screw or a coil toward a toner replenishing port corresponding to a connecting portion with a developing device or an image forming apparatus toner replenishing path (which will be described in the configuration in which toner is directly replenished to the developing container in the future). (032) makes it possible to transport the toner, and the conveying means is configured to be connectable to a main body driving unit (not shown), and the main body driving unit and the conveying means are connected by a known method such as a clutch, The non-connection can be controlled, and the toner replenishment drive can be freely performed. The amount of toner replenishment can be controlled by the drive time of the drive unit. For example, control such as changing the drive time in response to the change in toner fluidity in a temperature and humidity environment is also possible.
In the developing device (033), a toner transporting member (not shown) such as a screw for transporting the toner replenished from the upper toner supply container to the entire longitudinal direction, and an agitator (034) mainly stirring the toner in the device. ) And a developing roller (035) which is a toner carrier, and a supply roller (036) which is mainly made of a sponge material capable of supplying toner to the developing roller. The toner moved to the developing roller (035) by the supply roller (036) is made uniform according to the surface potential of the photosensitive drum (042) after the toner layer adhering to the developing roller surface is made uniform by the regulating blade (041). An amount of toner moves to the surface of the photosensitive drum (042) and is transferred to a transfer target by a transfer unit (not shown). As described above, the toner that has moved to the photoconductor drum (042) and remains on the photoconductor as a transfer residue is removed by the cleaning means, and is then collected by installing a waste toner container in the image forming apparatus.

The developer of the present invention can also be used in an image forming apparatus provided with a process cartridge as shown in FIG.
In the present invention, among the components such as the latent image carrier, the charging unit, the developing unit, and the cleaning unit, a plurality of components are integrally combined as a process cartridge. It is configured to be detachable from the image forming apparatus main body.
The process cartridge shown in FIG. 5 includes a latent image carrier, a charging unit, a developing unit, and a cleaning unit. In operation, the latent image carrier is driven to rotate at a predetermined peripheral speed. In the rotation process, the latent image carrier is uniformly charged with a positive or negative predetermined potential on its peripheral surface by the charging means, and then receives image exposure light from an image exposure means such as slit exposure or laser beam scanning exposure, In this way, electrostatic latent images are sequentially formed on the peripheral surface of the latent image carrier, and the formed electrostatic latent images are then developed with toner by the developing means, and the developed toner images are transferred from the paper feeding unit to the latent image carrier. And the transfer means are sequentially transferred to the transfer material fed in synchronization with the rotation of the latent image carrier. The transfer material that has received the image transfer is separated from the surface of the latent image carrier, introduced into the image fixing means, and fixed on the image, and printed out as a copy (copy) or print (print). The surface of the latent image carrier after the image transfer is cleaned by removing the transfer residual toner by the cleaning means, and after being further discharged, it is repeatedly used for image formation.

  EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited to the following Example.

Example 1
[Creation of urethane coated beads]
Sand blasting was performed on alumina beads having a diameter of 10 mm so that the surface roughness Ra after urethane coating was 5 μm.
In addition, surface roughness Ra in this invention is measured based on JISB0601 method, and Ra represents the centerline average roughness of a to-be-measured surface. The surface roughness Ra was measured using a surface roughness shape measuring device Surfcom 570A.

3 parts by weight of hexamethylene diisocyanate D170N manufactured by Mitsui Chemicals, 2.5 parts by weight of polyurethane polyol A2789 manufactured by the company, 4.8 parts by weight of carbon black manufactured by Fuji Pigment, 2.5 parts by weight of methyl ethyl ketone, 6 parts by weight of butyl acetate, 54 of ethyl acetate A coating solution was prepared by dissolving in 0.2 part by weight of a mixed solvent and adding 0.21 part by weight of dioctyltin acetate to the catalyst.
Alumina beads subjected to the sandblasting treatment are put into the mixed layer containing the prepared coating solution and sufficiently dipped, and then annealed at a temperature of 150 ° C. for 4 hours, and the coating film is cured. A urethane-coated treated bead coated uniformly on the entire surface was obtained.

[Production of toner]
[Production of vinyl resin fine particle dispersion 1]
In a reaction vessel equipped with a cooling tube, a stirrer, and a nitrogen introduction tube, 0.7 part of sodium dodecyl sulfate and 498 parts of ion-exchanged water were added and dissolved by heating to 80 ° C. with stirring, and then potassium persulfate. A solution prepared by dissolving 2.6 parts in 104 parts of ion-exchanged water was added, and 15 minutes later, a monomer mixture of 200 parts of styrene monomer and 4.2 parts of n-octanethiol was added dropwise over 90 minutes, Thereafter, the polymerization reaction was carried out at 80 ° C. for another 60 minutes.
Then, it cooled and the white vinyl resin fine particle dispersion 1 was obtained. The obtained dispersion was placed in a 2 ml petri dish and the dried solid obtained by evaporating the dispersion medium was measured. The number average molecular weight was 8,300, the weight average molecular weight was 16,900, and Tg was 83 ° C.

[Synthesis of Polyester 1]
229 parts of bisphenol A ethylene oxide 2-mole adduct, 529 parts of bisphenol A propylene oxide 2-mole adduct, 208 parts of terephthalic acid, 46 parts of adipic acid, and dibutyltin in a reaction vessel equipped with a condenser and a nitrogen introducing tube 2 parts of oxide were charged and reacted at 230 ° C. for 8 hours under normal pressure. Next, after reacting under reduced pressure of 10 to 15 mmHg for 5 hours, 44 parts of trimellitic anhydride was added to the reaction vessel and reacted at 180 ° C. for 2 hours under normal pressure to synthesize [Polyester 1]. did.
[Polyester 1] obtained had a number average molecular weight of 2500, a weight average molecular weight of 6700, a glass transition temperature of 43 ° C., and an acid value of 25 mgKOH / g.

[Prepolymer synthesis]
In a reaction vessel equipped with a cooling pipe, a stirrer and a nitrogen introduction pipe, 682 parts of bisphenol A ethylene oxide 2-mole adduct, 81 parts of bisphenol A propylene oxide 2-mole adduct, 283 parts of terephthalic acid, trimellitic anhydride 22 And 2 parts of dibutyltin oxide were added, reacted at 230 ° C. under normal pressure for 8 hours, and further reacted at reduced pressure of 10 to 15 mmHg for 5 hours to obtain [Intermediate Polyester 1].
[Intermediate Polyester 1] had a number average molecular weight of 2,100, a weight average molecular weight of 9,500, Tg of 55 ° C., an acid value of 0.5, and a hydroxyl value of 49.
Next, 411 parts of [Intermediate polyester 1], 89 parts of isophorone diisocyanate, and 500 parts of ethyl acetate are placed in a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen introduction tube, and reacted at 100 ° C. for 5 hours. Polymer 1] was obtained. [Prepolymer 1] had a free isocyanate weight% of 1.53%.

[Manufacture of master batch 1]
Carbon black: 40 parts, polyester 1:60 parts, and water: 30 parts were mixed with a Henschel mixer to obtain a mixture in which water was soaked into the pigment aggregate. This was kneaded for 45 minutes with two rolls set at a roll surface temperature of 130 ° C. and pulverized to a size of 1 mm with a pulverizer to obtain [Masterbatch 1].

<Water phase creation process>
970 parts of ion-exchanged water, 40 parts of a 25 wt% aqueous dispersion of organic resin fine particles (styrene-methacrylic acid-butyl acrylate-methacrylic acid ethylene oxide adduct sulfate sodium salt copolymer) for dispersion stabilization, dodecyl diphenyl ether When 95 parts of a 48.5% aqueous solution of sodium disulfonate and 98 parts of ethyl acetate were mixed and stirred, the pH reached 6.2. A 10% aqueous sodium hydroxide solution was added dropwise thereto to adjust the pH to 9.5 to obtain [Aqueous Phase 1].

<Oil phase preparation process>
In a container equipped with a stir bar and a thermometer, 545 parts of [Polyester 1], 181 parts of [paraffin wax (melting point 74 ° C.)] and 1450 parts of ethyl acetate are charged, and the temperature is raised to 80 ° C. with stirring and remains at 80 ° C. After holding for 5 hours, it was cooled to 30 ° C. in 1 hour. Next, 500 parts of [Masterbatch 1] and 100 parts of ethyl acetate were charged in a container and mixed for 1 hour to obtain [Raw material solution 1].
[Raw material solution 1] 1500 parts are transferred to a container, and using a bead mill (Ultra Visco Mill, manufactured by Imex Co., Ltd.), liquid feeding speed is 1 kg / hr, disk peripheral speed is 6 m / sec, and 0.5 mm zirconia beads are 80% by volume. The pigment and WAX were dispersed under the conditions of filling and 3 passes. Next, 655 parts of a 66% ethyl acetate solution of [Polyester 1] was added, followed by one pass with a bead mill under the above conditions to obtain [Pigment / WAX Dispersion 1].
[Pigment / WAX Dispersion 1] 976 parts were mixed for 1 minute at 5,000 rpm with a TK homomixer (manufactured by Tokushu Kika), and then 88 parts of [Prepolymer 1] were added to a TK homomixer (tokushu Tokukai). Was mixed at 5,000 rpm for 1 minute to obtain [Oil Phase 1]. The solid content of [Oil Phase 1] obtained was measured to be 52.0% by weight, and the amount of ethyl acetate based on the solid content was 92% by weight.

<Core particle creation process>
Add 1200 parts of [Aqueous Phase 1] to the obtained [Oil Phase 1], and cool in a water bath to suppress the temperature rise due to shear heat of the mixer so that the temperature in the liquid is in the range of 20-23 ° C. , Adjusted at a rotation speed of 8,000-15,000 rpm using a TK homomixer and mixed for 2 minutes, then adjusted at a rotation speed of 130-350 rpm with a three-one motor with an anchor blade attached for 10 minutes The mixture was stirred to obtain [core particle slurry 1] in which oil phase droplets serving as core particles were dispersed in an aqueous phase.

<Resin fine particle adhesion process>
[Vinyl resin fine particle dispersion 1] 106 parts in a state where the liquid temperature is 22 ° C. while stirring [core particle slurry 1] with a three-one motor with anchor blades adjusted at a rotational speed of 130 to 350 rpm. And 71 parts of ion-exchanged water (solid content concentration 15%) were added dropwise over 3 minutes. After dropping, the number of rotations was adjusted to 200 to 450 rpm, and stirring was continued for 30 minutes to obtain [Composite Particle Slurry 1]. When 1 ml of [Composite Particle Slurry 1] was taken and diluted to 10 ml and centrifuged, the supernatant was transparent.

<Desolvation process>
[Composite particle slurry 1] was put into a container equipped with a stirrer and a thermometer, and the solvent was removed at 30 ° C. for 8 hours while stirring to obtain [Dispersion slurry 1]. When [Dispersion Slurry 1] was placed on a small amount of slide glass and observed with an optical microscope at a magnification of 200 times with a cover glass in between, uniform colored particles were observed. Further, when 1 ml of [Dispersion Slurry 1] was taken and diluted to 10 ml and centrifuged, the supernatant was transparent.

<Washing and drying process>
[Dispersion Slurry 1] After filtering 100 parts under reduced pressure,
(1): 100 parts of ion-exchanged water was added to the filter cake, mixed with a TK homomixer (10 minutes at 12,000 rpm), and then filtered.
(2): 900 parts of ion-exchanged water was added to the filter cake of (1), ultrasonic vibration was applied, and the mixture was mixed with a TK homomixer (30 minutes at 12,000 rpm), and then filtered under reduced pressure. This operation was repeated so that the electric conductivity of the reslurry liquid was 10 μC / cm or less.
(3): 10% hydrochloric acid was added so that the reslurry liquid of (2) had a pH of 4, and the mixture was filtered as it was with a three-one motor for 30 minutes.
(4): 100 parts of ion-exchanged water was added to the filter cake of (3), mixed with a TK homomixer (10 minutes at 12,000 rpm) and then filtered. This operation was repeated so that the reslurry liquid had an electric conductivity of 10 μC / cm or less to obtain [Filter Cake 1].
[Filtration cake 1] is dried at 45 ° C. for 48 hours in a circulating drier, sieved with a mesh opening of 75 μm, [Colored resin particles 1] (volume average particle diameter (Dv) is 6.1 μm, Dv / Dn is 1.14) was obtained. When the obtained [colored resin particles 1] were observed with a scanning electron microscope, the vinyl resin was uniformly attached to the surface of the core particles.

<External treatment process>
[Colored resin particles 1] 1.2 parts by mass of TS530 manufactured by Cabozil, which is inorganic fine particles, was added to 100 parts by mass, and mixed with a Henschel mixer.

<Bead mixing process>
The obtained toner was charged in a ball mill (BM-10: manufactured by Seiwa Giken Co., Ltd.) with alumina beads having a diameter of 10 mm at a weight ratio of toner / beads = 0.65, and the number of rotations and mixing time were adjusted to be predetermined. The mixture was mixed until an external additive adhesion strength was obtained to prepare a bead-treated toner, and then coarse particles such as aggregated particles were removed with a 250 mesh sieve.
The resulting toner had an external additive adhesion strength of 80%, a particle size of 6.1 μm, and a fine powder ratio of 1.4% by number.

(Example 2)
The same procedure as in Example 1 was performed except that sandblasting and urethane coating were performed so that the surface roughness Ra of the alumina beads was 1 μm.

(Example 3)
The same procedure as in Example 1 was performed except that sandblasting and urethane coating were performed so that the surface roughness Ra of the alumina beads was 20 μm.

Example 4
The same procedure as in Example 1 was performed except that sandblasting and urethane coating were performed so that the surface roughness Ra of the alumina beads was 50 μm.

(Example 5)
Example 1 was repeated except that alumina beads having a diameter of 5 mm were used.

(Example 6)
The same procedure as in Example 1 was performed except that the mixing ratio of toner and beads (toner / beads) was added at a ratio of 0.4.

(Example 7)
The same procedure as in Example 1 was performed except that the mixing ratio of toner and beads (toner / beads) was added at a ratio of 0.7.

(Comparative Example 1)
The procedure was the same as Example 1 except that the bead mixing treatment was not performed.

(Comparative Example 2)
Example 1 was repeated except that the alumina beads were not urethane coated.

(Comparative Example 3)
The same procedure as in Example 1 was performed except that the urethane coating amount of the alumina beads was adjusted to obtain beads having coating film defects.

(Comparative Example 4)
The same procedure as in Example 1 was performed except that sandblasting and urethane coating were performed so that the surface roughness Ra of the alumina beads was 60 μm.

(Comparative Example 5)
The same procedure as in Example 1 was performed except that sandblasting and urethane coating were performed so that the surface roughness Ra of the alumina beads was 0.5 μm.

(Comparative Example 6)
Example 1 was repeated except that the alumina beads were not sandblasted.

(Comparative Example 7)
Example 1 was repeated except that alumina beads having a diameter of 2 mm were used.

(Comparative Example 8)
The same procedure as in Example 1 was performed except that the mixing ratio of toner and beads (toner / beads) was added at a ratio of 0.3.

(Comparative Example 9)
The same procedure as in Example 1 was performed except that the mixing ratio of toner and beads (toner / beads) was added at a ratio of 0.8.

[Evaluation]
(Image evaluation)
Using Ricoh's Ipsio C310, the obtained toner is charged, and a predetermined print pattern with a printing rate of 6% is printed on a half-printed image after printing 1500 sheets continuously in an N / N environment (23 ° C., 45%). The white solid (white paper) printed image was visually observed and evaluated.
As evaluation items, filming on the developing roller / vertical white streaks on the solid were visually evaluated, and a level having no problem in image quality was marked with ◯, and a level having problems in actual use was marked with x.

(External additive adhesion strength measurement method)
Adhesive strength of the external additive was obtained by adding 2 g of toner to 30 mL of a 10-fold diluted surfactant solution and thoroughly mixing it, then applying energy at 40 W for 1 minute using an ultrasonic homogenizer to separate and wash the toner. Thereafter, a drying treatment is performed, and the ratio of the amount of inorganic particles attached before and after the treatment is calculated using a fluorescent X-ray analyzer.
The fluorescent X-ray analysis was performed by applying a force of 1 N / cm ² for 60 seconds to ² g each of the dry toner obtained by the above treatment and the pre-treatment toner using a wavelength dispersion type fluorescent X-ray analyzer XRF1700 manufactured by Shimadzu Corporation. By preparing pellets, quantifying the elements unique to the inorganic fine particles (for example, silicon in the case of silica) by a calibration curve method, and dividing the amount of the inorganic fine particles after the treatment by the amount of the inorganic fine particles before the treatment, The additive adhesion strength was calculated.

(Particle size, fine powder rate)
Measurement was carried out by the following measuring method, and the particle diameter was a volume average particle diameter, and the fine powder ratio was a value of number% of 4 μm or less.
(Toner particle size measurement method)
The particle size distribution of the toner particles can be measured with a Coulter Counter TA-II or Coulter Multisizer II or III (both manufactured by Coulter).
The measurement method is described below.
First, 0.1 to 5 mL of a surfactant (preferably alkylbenzene sulfonate) is added as a dispersant to 100 to 150 mL of the electrolytic aqueous solution. Here, the electrolytic solution is a solution prepared by preparing a 1% NaCl aqueous solution using first grade sodium chloride. For example, ISOTON-II (manufactured by Coulter) can be used. Here, further add 2 to 20 mg of the measurement sample as a solid content.
The electrolytic solution in which the sample is suspended is subjected to a dispersion treatment with an ultrasonic disperser for about 1 to 3 minutes, and the measurement device is used to measure the volume and number of toner particles or toner using a 100 μm aperture as the aperture. Volume distribution and number distribution are calculated. From the obtained distribution, the volume average particle diameter (Dv) and the number average particle diameter (Dp) of the toner can be obtained.
As a channel, for example, less than 2.00 to 2.52 μm; less than 2.52 to 3.17 μm; 3.17 to less than 4.00 μm; 4.00 to less than 5.04 μm; 5.04 to less than 6.35 μm; 6.35 to less than 8.00 μm; 8.00 to less than 10.08 μm; 10.08 to less than 12.70 μm; 12.70 to less than 16.00 μm; 16.00 to less than 20.20 μm; Less than .40 μm; 25.40 to less than 32.00 μm; 13 channels of 32.00 to less than 40.30 μm are used, and particles having a particle size of 2.00 μm to less than 40.30 μm can be targeted.

上記の結果より、フィルミング原因物質は微粉及び外添剤のみではなく、また、特定ビーズと特定条件下で混合攪拌処理することによりフィルミング原因物質を除去できることが分かる。

From the above results, it is understood that the filming causative substance is not limited to the fine powder and the external additive, and the filming causative substance can be removed by mixing and stirring with specific beads under specific conditions.

(About Figures 2 and 3)
DESCRIPTION OF SYMBOLS 1 Latent image carrier 2 Charging device 7 Cleaning member 8 Intermediate transfer material 9 Recording medium 40 Developing roller 41 Supply roller 43 Regulating blade 44 Developer (FIG. 4)
030 Stirring paddle 031 Toner container 032 Conveying means 033 Developing device 034 Agitator 035 Developing roller 036 Supplying roller 041 Regulating blade 042 Photosensitive drum

JP 2002-207397 A JP 2000-330310 A Japanese Patent Laid-Open No. 7-311474 JP 7-271090 A JP 2007-86812 A JP 2010-160234 A

Claims (6)

A toner containing a binder resin, a colorant, a wax, and an external additive, which is obtained by adhering an external additive to toner base particles and further mixing and stirring with beads. The stirring process is performed at a toner to bead weight ratio (toner / bead) of 0.35 to 0.75, and the beads have an average particle size of 3 mm to 20 mm and a surface roughness Ra of 1 μm or more. A toner having a thickness of 50 μm or less and a resin-coated whole surface.   The toner according to claim 1, wherein the toner has an external additive adhesion strength of 75% or more and 85% or less.   The toner according to claim 1, wherein the beads have a specific gravity of 3.0 to 6.5 and a Vickers hardness of 10 or more.   The toner according to claim 1, wherein the beads are coated with a urethane resin.   The toner according to claim 1, wherein the external additive includes inorganic fine particles having an average primary particle size of 10 nm to 50 nm.   A developer comprising the toner according to any one of claims 1 to 5 and a carrier.

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