JP2013029638A - Toner for electrostatic charge image development - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide toner that allows a charge control agent remained on the surface of toner base particles even after application of heat or a mechanical hazard, has excellent low-temperature fixability and charge stability, and forms high-quality images without causing scumming or toner scattering and with less energy consumption.SOLUTION: Toner for electrostatic charge image development has toner base particles granulated from an oil-phase aqueous-medium dispersion or emulsion containing a toner material, and is formed by externally adding fine particles to the toner base particles having a charge control agent on the surface thereof. The charge control agent is a fluorine-modified ammonium salt; and the fine particle has the surface treated with a fluorine-based silane coupling agent, and the average particle diameter of 80 nm or more and 150 nm or less.

Description

  The present invention relates to a developer used for image formation using an electrophotographic process.

  In recent years, an electrophotographic image forming method is required to have a low-temperature fixing of a toner used in the image forming method from the viewpoint of energy saving. However, low-temperature-fixed toners tend to have low storage stability, and polyester resins that are advantageous for low-temperature fixing are often used.

Further, the recent demand for higher image quality is met by using so-called chemical toners such as a polymerization method in which the particle diameter is uniform and the particle diameter can be reduced.

However, in the chemical toner, it is difficult to cause the charge control agent for controlling the charging characteristics of the toner to be present at the interface between the oil phase and the aqueous medium and adhere to the toner particle surface. Then, a charge control material is attached.
However, toner that has improved low-temperature fixability by using a polyester resin having a low glass transition temperature has almost no charge control agent attached to the surface of the toner particles due to heat received at the developing section or mechanical hazard. It turned out to be gone.

Since the external additive also has a function as a spacer, the hazard received by the toner base particles can be mitigated.However, in a toner using a polyester resin having a low glass transition temperature, the external additive is easily embedded in the toner base particles. The external additive does not function effectively as a spacer, and the charge control function of the mother particles is lost.

Japanese Patent No. 3744829 of Patent Document 1 uses a rutile / anatase mixed crystal titanium oxide and hydrophobic silica that are difficult to embed in toner base particles, and the rutile / anatase mixed crystal titanium oxide adheres to the hydrophobic silica. In US Pat. No. 5,637, the toner is adhered to toner base particles to prevent burying of hydrophobic silica.

In addition, in Japanese Patent Application No. 2010-165259, silica particles are added to mother particles containing microcrystalline wax having an endothermic start temperature in DSC of 45 to 60 ° C. and a carbon number distribution in the range of 25 to 55. It is described that the silica particles can be prevented from adhering to the photoreceptor when fixed.

However, in these methods, a polyester resin having a low glass transition temperature and a toner having improved low-temperature fixability, the external additive is easily embedded in the toner base particles, and does not function effectively as a spacer. In the developing unit, toner particles having the charge control agent on the surface and toner particles having the charge control agent lost from the surface are mixed, resulting in variations in the toner charge amount in the developing device. An abnormal image occurs due to development on the image portion, toner scattering around the developing device, and the like.

The present invention has been made in order to solve the above-described problem. Even when subjected to heat or mechanical hazard, the charge control agent exists on the surface of the toner base particles, and both low-temperature fixability and charge stability are achieved. An object of the present invention is to provide a toner capable of forming a high-quality image that is energy-saving and free from background contamination and toner scattering.

As a result of diligent investigations by the present inventors to solve the above problems, a toner in which a fluorine-modified ammonium salt and fine particles having an average particle diameter of 80 nm or more and 150 nm or less that are surface-treated with a fluorine-based silane coupling agent are attached. In addition, the toner in which the fine particles are difficult to embed and desorb, has a spacer function, does not lose the charge control agent from the surface of the toner base particles even when subjected to heat or mechanical hazard, and does not vary in the amount of charged charge over a long period of time. It was found that can be obtained. The present invention has been completed based on such knowledge.

The said subject is solved by following (1)-(6) of this invention.
(1) “An electrostatic charge image developing toner having toner base particles granulated from an aqueous medium dispersion or emulsion of an oil phase containing a toner material, wherein the charge control agent is present on the surface of the toner base particles. Fine particles are externally added, the charge control agent is a fluorine-modified ammonium salt, and the fine particles are fine particles having an average particle diameter of 80 nm or more and 150 nm or less that are surface-treated with a fluorine-based silane coupling agent. Characterized toner for developing electrostatic image ",
(2) “Containing 0.5 to 5 parts by weight of fine particles having an average particle diameter of 80 to 150 nm and surface-treated with the fluorine-based silane coupling agent with respect to 100 parts by weight of toner base particles. The electrostatic charge image developing toner according to item (1), wherein:
(3) The binder resin of the toner base particles includes a polyester resin having a glass transition temperature of 30 ° C. or higher and 70 ° C. or lower, according to the item (1) or (2), Toner for developing electrostatic image ",
(4) "The electrostatic image developing toner according to any one of (1) to (3) above, wherein the fine particles are silica",
(5) “Developer comprising the electrostatic image developing toner according to the items (1) to (4) and a carrier”,
(6) “An image forming apparatus comprising the electrostatic image developing toner according to any one of (1) to (4)”.

  As will be understood from the following detailed and specific description, according to the present invention, the charge control agent exists on the surface of the toner base particles even when subjected to heat or mechanical hazard, and low temperature fixability and charge stability In addition, it is possible to provide a toner that can form a high-quality image that is energy-saving and has no background contamination and toner scattering.

It is a figure which shows an example of the image forming apparatus of this invention. It is a figure which shows the other example of the image forming apparatus of this invention. FIG. 3 is a diagram showing a tandem developing device of FIG. 2.

The toner of the present invention will be described in detail.
The toner of the present invention is a toner for developing an electrostatic charge image having toner base particles granulated from an aqueous medium dispersion or emulsion of an oil phase containing a toner material, and a toner base having a charge control agent on the surface. The particles are externally added to the particles, the charge control agent is a fluorine-modified ammonium salt, and the particles are particles having an average particle size of 80 nm or more and 150 nm or less surface-treated with a fluorine-based silane coupling agent. .

<Charge control agent>
The toner charge control agent of the present invention comprises a fluorine-modified quaternary ammonium salt.
As the quaternary ammonium salt modified with fluorine, any conventionally known quaternary ammonium salt can be used as long as it is modified with fluorine. Particularly, those having a perfluoroalkenyl group are preferable because even a small amount shows a sufficient effect. Can be used. Examples of those having a perfluoroalkenyl group include fluoroalkenyltrimethylammonium iodide (manufactured by Neos;

As the charge control agent, in addition to the fluorine-modified quaternary ammonium salt, other charge control agents can be used.
For example, nigrosine dye, triphenylmethane dye, chromium-containing metal complex dye, molybdate chelate pigment, rhodamine dye, alkoxy amine, alkylamide, phosphorus simple substance or compound, tungsten simple substance or compound, fluorine-based surface activity Agents, metal salts of salicylic acid, metal salts of salicylic acid derivatives, etc., and the content of the fluorine-modified quaternary ammonium salt in the charge control agent is preferably 70% or more.

  The content of the charge control agent in the toner is not particularly limited and may be appropriately selected depending on the intended purpose. For example, the content is preferably 0.01 to 5% by weight with respect to the binder resin, 0.05-2 weight% is still more preferable. When the content is less than 0.01% by weight, the charge controllability may not be obtained. When the content exceeds 5% by weight, the chargeability of the toner becomes too large, and the effect of the main charge control agent is reduced. As a result, the electrostatic attraction force with the developing roller increases, which may lead to a decrease in toner fluidity and a decrease in image density.

<Fine particles>
The fine particles of the present invention are those having an average particle size of 80 nm or more and 150 nm or less of primary particles surface-treated with a fluorine-based silane coupling agent. As the fluorine-based silane coupling agent, conventionally known ones can be used, but those having a fluorine-containing alkyl group are preferable. In particular, fine particles surface-treated with a silane coupling agent having a fluorine-containing alkyl group have very high repellency, and in combination with the particle size of 80 nm to 150 nm, the toner can be subjected to heat and mechanical hazards. It is difficult to be buried in the mother particle and has a spacer function for a long time.
When the average particle size of the fine particles is less than 80 nm, the spacer function is small and the charge control agent may be lost.
The content of the fine particles surface-treated with the fluorine-based silane coupling agent is preferably 0.5 parts by weight or more and 5 parts by weight or less with respect to 100 parts by weight of the toner base particles.

  Examples of the fine particles having an average particle diameter of 80 nm or more and 150 nm or less that have been surface-treated with the fluorine-based silane coupling agent in the toner of the present invention include silica, alumina, titanium oxide, barium titanate, magnesium titanate, calcium titanate, and titanium. Strontium acid, zinc oxide, tin oxide, silica sand, clay, mica, wollastonite, diatomaceous earth, chromium oxide, cerium oxide, bengara, antimony trioxide, magnesium oxide, zirconium oxide, barium sulfate, barium carbonate, calcium carbonate, Silicon carbide, silicon nitride, or the like can be used, but silica is preferable from the viewpoint of charge control.

  The average particle size of the fine particles in the present invention is a volume average particle size unless otherwise specified, and is determined by an ultracentrifugal automatic particle size distribution analyzer: LA-700 (manufactured by Horiba Seisakusho). At this time, the particle diameter (Median diameter) corresponding to 50% of the cumulative distribution was calculated.

<Binder resin>
As the binder resin for the toner of the present invention, a conventionally known resin can be used as the toner resin, and it can be appropriately selected according to the purpose. However, it is preferable to contain a polyester resin from the viewpoint of low-temperature fixability.

-Polyester resin-
The polyester resin can be obtained by dehydration condensation of a polyhydric alcohol and a polyvalent carboxylic acid.

Examples of the polyhydric alcohol include ethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, diethylene glycol, triethylene glycol, 1,5-pentanediol, , 6-hexanediol, neopentyl glycol, 2-ethyl-1,3-hexanediol, hydrogenated bisphenol A, divalent alcohols obtained by adding cyclic ethers such as ethylene oxide and propylene oxide to bisphenol A, etc. Is mentioned.
In order to crosslink the polyester resin, sorbitol, 1,2,3,6-hexanetetrol, 1,4-sorbitan, pentaerythritol, dipentaerythritol, tripentaerythritol, 1,2,4-butanetriol 1,2,5-pentatriol, glycerol, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane, 1,3,5-trihydroxybenzene, etc. It is preferable to use a trivalent or higher alcohol together.

  Examples of the polyvalent carboxylic acid include benzene dicarboxylic acids such as phthalic acid, isophthalic acid, and terephthalic acid or anhydrides thereof, and alkyldicarboxylic acids such as succinic acid, adipic acid, sebacic acid, and azelaic acid, or anhydrides thereof. Unsaturated dibasic acids such as maleic acid, citraconic acid, itaconic acid, alkenyl succinic acid, fumaric acid, mesaconic acid, etc., unsaturated maleic anhydride, citraconic anhydride, itaconic anhydride, alkenyl succinic anhydride, etc. Dibasic acid anhydride, trimet acid, pyrometic acid, 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, 2,5,7-naphthalenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid Acid, 1,2,4-butanetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, 1,3-dicar Xyl-2-methyl-2-methylenecarboxypropane, tetrakis (methylenecarboxy) methane, 1,2,7,8-octanetetracarboxylic acid, emporic trimer acid, anhydrides thereof, partial lower alkyl esters, etc. It is done.

There is no restriction | limiting in particular as an acid value of the said polyester resin, Although it can select suitably according to the objective, 5-40 mgKOH / g is preferable and 10-30 mgKOH / g is still more preferable. When the acid value is less than 5 mgKOH / g, the affinity with paper as a main recording medium is lowered, so that the low-temperature fixability of the toner may be lowered, and it is difficult to obtain a negative chargeability. The image may deteriorate.
On the other hand, when the acid value exceeds 40 mgKOH / g, the image is likely to be deteriorated under an environment such as high temperature and high humidity, low temperature and low humidity, and the like.

  There is no restriction | limiting in particular as a hydroxyl value of the said polyester resin, Although it can select suitably according to the objective, 5-100 mgKOH / g is preferable and 20-60 mgKOH / g is still more preferable. When the hydroxyl value is less than 5 mgKOH / g, the affinity with paper as the main recording medium is lowered, so that the low-temperature fixability of the toner may be lowered, and the negative chargeability is hardly obtained. The image may be deteriorated. On the other hand, when the hydroxyl value exceeds 100 mgKOH / g, the image may be deteriorated because it is easily affected by the environment in an environment such as high temperature and high humidity or low temperature and low humidity.

In addition, the polyester resin has at least one peak in a molecular weight range of 3,000 to 50,000 in the molecular weight distribution of components soluble in THF from the viewpoint of toner fixing property and offset resistance. Preferably, it has at least one peak in a region having a molecular weight of 5,000 to 20,000. Furthermore, the component of the polyester resin soluble in THF preferably has a content of a component having a molecular weight of 100,000 or less of 60 to 100% by weight.
Here, the molecular weight distribution of the polyester resin can be measured, for example, by gel permeation chromatography (GPC) using THF as a solvent.

  The glass transition temperature (Tg) of the polyester resin is preferably 55 to 80 ° C., and more preferably 60 to 75 ° C. from the viewpoint of toner storage stability. When the Tg is 55 to 80 ° C., the toner has excellent stability during high-temperature storage, and the effect of softening the binder resin by the fixing auxiliary component can be obtained sufficiently. Excellent.

  The binder resin may further contain a resin other than the polyester resin. Examples of the resin other than the polyester resin include homopolymers or copolymers such as styrene monomers, acrylic monomers, and methacrylic monomers, polyol resins, phenol resins, silicone resins, polyurethane resins, Examples thereof include polyamide resin, furan resin, epoxy resin, xylene resin, terpene resin, coumarone indene resin, polycarbonate resin, and petroleum resin. Resins other than the polyester resin may be used alone or in combination of two or more.

<External additive>

As the external additive, inorganic fine particles can be used, for example, silica, alumina, titanium oxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate, zinc oxide, tin oxide, silica sand, clay, mica, Wollastonite, diatomaceous earth, chromium oxide, cerium oxide, bengara, antimony trioxide, magnesium oxide, zirconium oxide, barium sulfate, barium carbonate, calcium carbonate, silicon carbide, silicon nitride, etc. can be used. The primary particle size is preferably 5 to 100 nm.
Moreover, it is preferable that it is the hydrophobic silica and / or hydrophobic titanium oxide surface-treated with the fluidity improver from the viewpoint of charge imparting property.
When the surface is treated with a fluidity improver, the hydrophobicity of the inorganic fine particles is improved, and a decrease in fluidity and chargeability can be suppressed even under high humidity.

  Examples of the fluidity improver include silane coupling agents, silylating agents, organic titanate coupling agents, aluminum coupling agents, silicone oils, and modified silicone oils.

<Release agent>
As the mold release agent, an appropriate one can be selected from microcrystalline wax, paraffin wax, and ester wax.
The content of the release agent is not uniquely determined because the heat loss characteristic of the toner changes depending on the type of the release agent used, but is preferably not less than 1 part by weight and less than 30 parts by weight. If it is 1 part by weight or less, the hot offset resistance may be inferior. If it is 30 parts by weight or more, filming properties may be deteriorated and image fogging may occur.

<Colorant>
As a coloring agent, it can select suitably from well-known dyes and pigments according to the objective.
For example, 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, Pangdan, Pepper Red, Cadmium Red, Cadmium Mercury Red, Antimony Zhu, Permanent Red 4R, Para Red, Faise Red, Parachloro Ortho Nitroaniline Red, Resol Fast Scarlet G, Brilli 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 3 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 Examples include lead flower and lithopone.

The said colorant may be used individually by 1 type, and may use 2 or more types together.
The content of the colorant in the toner can be appropriately selected according to the purpose, but is usually 1 to 15% by weight, and preferably 5 to 12% by weight. This requires a certain amount of colorant adhesion when a low adhesion amount is formed with toner having a particle diameter of 3 to 6 μm. On the other hand, when the content of the colorant in the toner is less than 3% by weight, the coloring power of the toner is lowered. Insufficient spreadability may occur, and conversely, the concealment rate may be lowered and the electrical characteristics of the toner may be lowered.

  The colorant may be used as a master batch combined with a resin. Examples of such resins include polyesters, styrene or substituted polymers thereof, styrene copolymers, polymethyl methacrylate, polybutyl methacrylate, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, and epoxy resins. , Epoxy polyol resin, polyurethane, polyamide, polyvinyl butyral, polyacrylic acid resin, rosin, modified rosin, terpene resin, aliphatic hydrocarbon resin, alicyclic hydrocarbon resin, aromatic petroleum resin, chlorinated paraffin, paraffin wax Etc., and may be used alone or in combination of two or more.

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

  The masterbatch can be produced by applying a high shear force and mixing or kneading the resin and the colorant. At this time, it is preferable to add an organic solvent in order to enhance the interaction between the colorant and the resin. A so-called flushing method is also preferable in that the wet cake of the colorant can be used as it is, and it does not need to be dried. The flushing method is a method in which an aqueous paste containing water of a colorant is mixed or kneaded together with a resin and an organic solvent, and the colorant is transferred to the resin side to remove water and the organic solvent. For the mixing or kneading, for example, a high shear dispersion device such as a three-roll mill can be used.

-Polymerization method (aqueous granulation method)-
As a method for producing a toner by the polymerization method, for example, a toner material including a modified polyester resin capable of at least urea or urethane bond, a colorant, a release agent, and a fixing aid is dissolved or dispersed in an organic solvent. Let Then, the solution or dispersion is dispersed in an aqueous medium, subjected to a polyaddition reaction, the solvent of this dispersion is removed and washed.

The organic solvent can be appropriately selected according to the purpose, but preferably has a boiling point of less than 150 ° C. because it is easy to remove. Specifically, 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, And methyl isobutyl ketone. Of these, toluene, xylene, benzene, methylene chloride, 1,2-dichloroethane, chloroform, carbon tetrachloride and the like are preferable, and ethyl acetate is particularly preferable. These may be used alone or in combination of two or more.
The amount of the organic solvent used can be appropriately selected according to the purpose, but is preferably 40 to 300 parts by weight, more preferably 60 to 140 parts by weight, and more preferably 80 to 140 parts by weight with respect to 100 parts by weight of the toner material. More preferably, 120 parts by weight.

  Examples of the modified polyester resin capable of being bonded with urea or urethane include, for example, a polyester prepolymer having an isocyanate group (A) obtained by reacting a terminal carboxyl group or hydroxyl group of a polyester with a polyvalent isocyanate compound (PIC) (A). ) And the like. The modified polyester resin obtained by cross-linking and / or extending the molecular chain by the reaction of this polyester prepolymer and amines (B) improves the hot offset property while maintaining the low-temperature fixability of the toner. Can do.

  Examples of the polyvalent isocyanate compound (PIC) include aliphatic polyisocyanates (tetramethylene diisocyanate, hexamethylene diisocyanate, 2,6-diisocyanatomethylcaproate, etc.); alicyclic polyisocyanates (isophorone diisocyanate, cyclohexylmethane). Aromatic diisocyanates (tolylene diisocyanate, diphenylmethane diisocyanate, etc.); araliphatic diisocyanates (α, α, α ′, α′-tetramethylxylylene diisocyanate, etc.); isocyanates; And those blocked with oxime, caprolactam, and the like. These may be used individually by 1 type and may use 2 or more types together.

  The ratio of the polyvalent isocyanate compound (PIC) is preferably 5/1 to 1/1 as an equivalent ratio [NCO] / [OH] of the isocyanate group [NCO] and the hydroxyl group [OH] of the polyester having a hydroxyl group, 4/1 to 1.2 / 1 is more preferable, and 2.5 / 1 to 1.5 / 1 is still more preferable.

  As an isocyanate group contained per molecule in the polyester prepolymer (A) having the isocyanate group, one or more is preferable, an average of 1.5 to 3 is more preferable, and an average of 1.8 to 2.5 is preferable. More preferably.

Examples of amines (B) to be reacted with the polyester prepolymer include a divalent amine compound (B1), a trivalent or higher polyvalent amine compound (B2), an amino alcohol (B3), an amino mercaptan (B4), an amino acid (B5). ), B1 to B5 amino groups blocked (B6), and the like.
Examples of the divalent amine compound (B1) include aromatic diamines (phenylenediamine, diethyltoluenediamine, 4,4′-diaminodiphenylmethane, etc.); alicyclic diamines (4,4′-diamino-3,3′-). Dimethyl dicyclohexyl methane, diamine cyclohexane, isophorone diamine, etc.); aliphatic diamines (ethylene diamine, tetramethylene diamine, hexamethylene diamine, etc.) and the like.
Examples of the trivalent or higher polyvalent amine compound (B2) include diethylenetriamine and triethylenetetramine.
Examples of the amino alcohol (B3) include ethanolamine and hydroxyethylaniline.
Examples of the amino mercaptan (B4) include aminoethyl mercaptan and aminopropyl mercaptan.
Examples of the amino acid (B5) include aminopropionic acid and aminocaproic acid.
Examples of the block (B6) obtained by blocking the amino group (B1) to (B5) include ketimines obtained from the amines (B1) to (B5) and ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.). Compounds, oxazolidine compounds and the like. Among these amines (B), (B1) and a mixture of (B1) and a small amount of (B2) are particularly preferable.

The ratio of the amines (B) is equivalent to the equivalent ratio [NCO] / [NHx of the isocyanate group [NCO] in the polyester prepolymer (A) having an isocyanate group and the amino group [NHx] in the amine (B). ] Is preferably 1/2 to 2/1, more preferably 1.5 / 1 to 1 / 1.5, and still more preferably 1.2 / 1 to 1 / 1.2.
According to the method for producing a toner by the polymerization method as described above, a toner having a small particle diameter and a spherical shape can be produced at low cost with little environmental load.

  In addition to the modified polyester, an unmodified polyester resin is also used for securing low-temperature fixability and storage stability. The weight average molecular weight of the unmodified polyester resin used is preferably 1000 to 30000, and more preferably 1500 to 15000. When the weight average molecular weight is less than 1000, the heat resistant storage stability may be lowered. For this reason, it is preferable that content of the component whose weight average molecular weight is less than 1000 is 8-28 weight%. On the other hand, if the weight average molecular weight exceeds 30000, the low-temperature fixability may be lowered.

The glass transition temperature of the unmodified polyester resin is usually 30 to 70 ° C, more preferably 35 to 60 ° C, and still more preferably 35 to 55 ° C. When the glass transition temperature is less than 30 ° C., the heat-resistant storage stability of the toner may be lowered, and when it exceeds 70 ° C., the low-temperature fixability may be lowered.
The hydroxyl value of the unmodified polyester resin is preferably 5 mgKOH / g or more, more preferably 10 to 120 mgKOH / g, and still more preferably 20 to 80 mgKOH / g. When the hydroxyl value is less than 5 mgKOH / g, it may be difficult to achieve both heat-resistant storage stability and low-temperature fixability.
The acid value of the unmodified polyester resin is preferably 1.0 to 50.0 mgKOH / g, and more preferably 1.0 to 30.0 mgKOH / g. Thereby, the toner is easily negatively charged.

  When the toner contains an unmodified polyester resin, the weight ratio of the polyester prepolymer having an isocyanate group to the unmodified polyester resin is preferably 5/95 to 25/75, more preferably 10/90 to 25/75. preferable. When the weight ratio is less than 5/95, the hot offset resistance may be lowered, and when it exceeds 25/75, the low-temperature fixability and the glossiness of the image may be lowered.

  In the present invention, the aqueous medium preferably contains a polymer dispersant. The polymer dispersant is preferably a water-soluble polymer. The water-soluble polymer can be appropriately selected from known ones, and examples thereof include sodium carboxymethyl cellulose, hydroxyethyl cellulose, and polyvinyl alcohol. These may be used alone or in combination of two or more.

  When the toner material is emulsified or dispersed in the aqueous medium using the liquid containing the toner material, the liquid containing the toner material is preferably dispersed in the aqueous medium while stirring.

  A known disperser or the like can be appropriately used for the dispersion. Specific examples of the disperser include a low speed shear disperser, a high speed shear disperser, a friction disperser, a high pressure jet disperser, and an ultrasonic disperser. Especially, since the particle diameter of a dispersion (oil droplet) can be controlled to 2-20 micrometers, a high-speed shearing disperser is preferable.

  When a high-speed shearing disperser is used, conditions such as the number of rotations, dispersion time, dispersion temperature and the like can be appropriately selected according to the purpose. The rotation speed is preferably 1000 to 30000 rpm, more preferably 5000 to 20000 rpm. In the case of a batch system, the dispersion time is preferably 0.1 to 5 minutes, and the dispersion temperature is preferably 0 to 150 ° C. and more preferably 40 to 98 ° C. under pressure. In general, the dispersion is easier when the dispersion temperature is higher.

<Career>
The carrier can be appropriately selected according to the purpose, but a carrier having a core material and a resin layer covering the core material is preferable.
The material of the core material can be appropriately selected from known materials, and examples thereof include 50 to 90 emu / g manganese-strontium-based material, manganese-magnesium-based material, and the like. In order to ensure the image density, it is preferable to use a highly magnetized material such as iron powder of 100 emu / g or more and magnetite of 75 to 120 emu / g. In addition, it is preferable to use a low-magnetization material such as 30-80 emu / g of copper-zinc system because it can reduce the impact of the developer in a spiked state on the photoconductor and is advantageous for high image quality. . These may be used alone or in combination of two or more.

  The volume average particle diameter of the core material is preferably 10 to 150 μm, and more preferably 40 to 100 μm. If the volume average particle size is less than 10 μm, fine particles are increased in the carrier, and magnetization per particle may be reduced to cause carrier scattering. If it exceeds 150 μm, the specific surface area is decreased, and In the case of a full color with many solid portions, the reproduction of the solid portions may be deteriorated.

The material of the resin layer can be appropriately selected from known resins according to the purpose, but amino resin, polyvinyl resin, polystyrene resin, polyhalogenated olefin, polyester resin, polycarbonate resin, polyethylene , Polyvinyl fluoride, polyvinylidene fluoride, polytrifluoroethylene, polyhexafluoropropylene, copolymer of vinylidene fluoride and acrylic monomer, copolymer of vinylidene fluoride and vinyl fluoride, tetrafluoroethylene and vinylidene fluoride Examples include fluoroterpolymers such as copolymers of monomers having no fluoro group, silicone resins, and the like. These may be used alone or in combination of two or more.

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

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

The resin layer can be formed by preparing a coating solution by dissolving a silicone resin or the like in a solvent, and then applying and drying the coating solution on the surface of the core using a known coating method, followed by baking. it can. As a coating method, a dip coating method, a spray method, a brush coating method, or the like can be used. The solvent can be appropriately selected depending on the purpose, and examples thereof include toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, and butyl cellosolve. The baking may be an external heating method or an internal heating method, a method using a fixed electric furnace, a fluid electric furnace, a rotary electric furnace, a burner furnace, a method using a microwave, or the like. Is mentioned.

The content of the resin layer in the carrier is preferably 0.01 to 5.0% by weight. When this content is less than 0.01% by weight, a uniform resin layer may not be formed on the surface of the core material. May occur, and the uniformity of the carrier may be reduced.
The content of the carrier in the two-component developer is preferably 90 to 98% by weight, and more preferably 93 to 97% by weight.

(Image forming method, image forming apparatus)
The image forming method of the present invention preferably has at least an electrostatic latent image forming step, a developing step, a transfer step, and a fixing step, more preferably a cleaning step. You may have a process, a recycling process, a control process, etc.
The image forming apparatus of the present invention preferably includes at least an electrostatic latent image carrier, an electrostatic latent image forming unit, a developing unit, a transfer unit, and a fixing unit, and further includes a cleaning unit. Preferably, it may have, for example, a static elimination means, a recycling means, a control means, etc. as necessary.

  The image forming method of the present invention can be carried out using the image forming apparatus of the present invention, the electrostatic latent image forming step using an electrostatic latent image forming unit, and the developing step using a developing unit. The transfer step can be performed using a transfer unit, the fixing step can be performed using a fixing unit, and the other steps can be performed using other units.

  The electrostatic latent image forming step is a step of forming an electrostatic latent image on an electrostatic latent image carrier such as a photoconductive insulator or a photoconductor. The material, shape, structure, size and the like of the electrostatic latent image carrier are not particularly limited and can be appropriately selected from known ones, but the shape is preferably a drum shape. Examples of the photoreceptor include inorganic photoreceptors such as amorphous silicon and selenium, and organic photoreceptors such as polysilane and phthalopolymethine. Among these, an amorphous silicon photoconductor is preferable because of its long life.

  The electrostatic latent image is formed, for example, by uniformly charging the surface of the electrostatic latent image carrier and then exposing it like an image, and can be formed using electrostatic latent image forming means. . The electrostatic latent image forming means includes, for example, a charger that applies a voltage to the surface of the electrostatic latent image carrier and uniformly charges it, and an exposure device that exposes the surface of the electrostatic latent image carrier imagewise At least.

  The charger is not particularly limited. For example, a known contact charger provided with a conductive or semiconductive roll, brush, film, rubber blade, etc., non-contact using corona discharge such as corotron, scorotron, etc. Examples include a charger.

  The exposure device is not particularly limited as long as it can be exposed like an image to be formed on the surface of the electrostatic latent image carrier charged by the charger. For example, a copying optical system, a rod lens array system, a laser Various exposure devices such as an optical system and a liquid crystal shutter optical system may be mentioned. In addition, you may employ | adopt the light back system which performs imagewise exposure from the back surface side of an electrostatic latent image carrier.

  The developing step is a step of developing an electrostatic latent image with the toner of the present invention to form a visible image, and the visible image can be formed using a developing unit. The developing unit is not particularly limited as long as it can be developed with the toner of the present invention. For example, a developing device that stores the developer of the present invention and can apply toner to a latent electrostatic image in a contact or non-contact manner. A developing device equipped with the developer container of the present invention is preferable. Examples include a stirrer that charges the developer of the present invention by frictional stirring and a rotatable magnet roller. In the developing device, for example, the toner and the carrier are mixed and stirred, and the toner is charged by friction at that time, and held on the surface of the rotating magnet roller in a raised state to form a magnetic brush. The magnet roller is disposed in the vicinity of the electrostatic latent image carrier, and a part of the toner constituting the magnetic brush formed on the surface of the magnet roller is electrically attracted by the electrostatic latent image carrier. Move to the surface. As a result, the electrostatic latent image is developed with toner, and a toner image is formed on the surface of the electrostatic latent image carrier.

  The transfer step is a step of transferring the toner image to a recording medium by charging the electrostatic latent image carrier on which the toner image is formed using, for example, a transfer charger. can do. At this time, the transfer step preferably includes a primary transfer step of transferring the toner image onto the intermediate transfer member, and a secondary transfer step of transferring the toner image transferred onto the intermediate transfer member onto the recording medium. Further, the transfer step includes a primary transfer step in which a toner image of two or more colors, preferably a full color toner, is used to transfer a toner image of each color onto an intermediate transfer member to form a composite toner image; It is more preferable to have a secondary transfer step of transferring the composite toner image formed on the recording medium.

The transfer means includes a primary transfer means for transferring a toner image onto an intermediate transfer member to form a composite toner image, and a secondary transfer means for transferring the composite toner image formed on the intermediate transfer member onto a recording medium. It is preferable to have. The intermediate transfer member is not particularly limited, and examples thereof include an endless transfer belt. The transfer means (primary transfer means and secondary transfer means) preferably has at least a transfer device that charges and separates the toner image formed on the electrostatic latent image carrier on the recording medium side. The transfer means can have one or more transfer devices.

Examples of the transfer device include a corona transfer device using corona discharge, a transfer belt, a transfer roller, a pressure transfer roller, and an adhesive transfer device.
The recording medium is not particularly limited, and can be appropriately selected from known recording media (recording paper).

The fixing step is a step of fixing the toner image transferred to the recording medium, and can be fixed using a fixing unit. When two or more color toners are used, the toner may be fixed each time the toner of each color is transferred to the recording medium, or the toner of all colors may be transferred to the recording medium and fixed in a stacked state. Also good. The fixing unit is not particularly limited, and a known heating and pressing unit can be used. Examples of the heating and pressing means include a combination of a heating roller and a pressing roller, a combination of a heating roller, a pressing roller, and an endless belt. At this time, heating temperature is 80-200 degreeC normally. If necessary, for example, a known optical fixing device may be used together with the fixing unit or instead of the fixing unit.

  The neutralization step is a step of neutralizing by applying a neutralization bias to the electrostatic latent image carrier, and can be neutralized using a neutralization unit. The neutralization means is not particularly limited as long as a neutralization bias can be applied to the electrostatic latent image carrier. For example, a neutralization lamp can be used.

  The cleaning step is a step of removing toner remaining on the electrostatic latent image carrier and can be cleaned using a cleaning unit. The cleaning means is not particularly limited as long as the toner remaining on the electrostatic latent image carrier can be removed. For example, a magnetic brush cleaner, electrostatic brush cleaner, magnetic roller cleaner, blade cleaner, brush cleaner, A web cleaner or the like can be used.

  The recycling step is a step of recycling the toner removed in the cleaning step to the developing means, and can be recycled using the recycling means. The recycling unit is not particularly limited, and a known conveyance unit or the like can be used.

  The said control process is a process of controlling each process, and can be controlled using a control means. The control means is not particularly limited as long as the operation of each means can be controlled. For example, a sequencer, a computer, or the like can be used. In practice, it is important to set the developer temperature to 50 ° C. or lower while feeding back temperature sensor information for monitoring the temperature inside the apparatus.

  FIG. 1 shows an example of an image forming apparatus of the present invention. The image forming apparatus (100) includes a photosensitive drum (10) as an electrostatic latent image carrier, a charging roller (20) as a charging unit, an exposure device (not shown) as an exposure unit, and a developing unit. The developing device (45), the intermediate transfer member (50), a cleaning device (60) having a cleaning blade as a cleaning means, and a static elimination lamp (70) as a static elimination means.

  The intermediate transfer member (50) is an endless belt, is stretched by three rollers (51) arranged on the inner side thereof, and can move in the direction of the arrow. A part of the three rollers (51) also functions as a transfer bias roller capable of applying a predetermined transfer bias (primary transfer bias) to the intermediate transfer member (50).

  Further, a cleaning device (90) having a cleaning blade is disposed in the vicinity of the intermediate transfer member (50). Further, a transfer roller (80) as a transfer means capable of applying a transfer bias for transferring (secondary transfer) the toner image to the recording paper (95) is disposed to face the intermediate transfer body (50). Has been.

Further, around the intermediate transfer member (50), a corona charger (52) for applying a charge to the toner image on the intermediate transfer member (50) includes a photosensitive drum (10) and the intermediate transfer member (50). ) And the contact portion between the intermediate transfer member (50) and the recording paper (95).
A developing device (45) for each color of black (K), yellow (Y), magenta (M), and cyan (C) includes a developer container (42), a developer supply roller (43), a developing roller ( 44).

  In the image forming apparatus (100), after the photosensitive drum (10) is uniformly charged by the charging roller (20), the exposure light L is imaged on the photosensitive drum (10) by the exposure apparatus (not shown). Exposure is performed to form an electrostatic latent image. Next, the electrostatic latent image formed on the photosensitive drum (10) was developed by supplying a developer from the developing device (45) to form a toner image, and then applied from the roller (51). The toner image is transferred (primary transfer) onto the intermediate transfer member (50) by the transfer bias. Further, the toner image on the intermediate transfer member (50) is given a charge by the corona charger (52) and then transferred (secondary transfer) onto the recording paper (95). The toner remaining on the photosensitive drum (10) is removed by the cleaning device (60), and the photosensitive drum (10) is once discharged by the discharging lamp (70).

FIG. 2 shows another example of the image forming apparatus of the present invention. The image forming apparatus shown in FIG. 2 is a tandem color image forming apparatus, and includes a copying apparatus main body (150), a paper feed table (200), a scanner (300), and an automatic document feeder (ADF) (400). Have
The copying machine main body (150) is provided with an endless belt-like intermediate transfer member (50) at the center. The intermediate transfer member (50) is stretched around the support rollers (14), (15) and (16), and can rotate in the direction of the arrow.
A cleaning device (17) for removing toner remaining on the intermediate transfer member (50) is disposed in the vicinity of the support roller (15). The intermediate transfer member (50) stretched by the support roller (14) and the support roller (15) is provided with four image forming units (18, yellow, cyan, magenta, and black) along the transport direction. ) Are arranged in parallel with each other, and a tandem developing device (120) is arranged. As shown in FIG. 3, the image forming means (18) for each color includes a photosensitive drum (10), a charging roller (20) for uniformly charging the photosensitive drum (10), and a photosensitive drum (10). A developing device (45) for developing a toner image by developing the electrostatic latent image formed on the toner with a developer of each color of black (K), yellow (Y), magenta (M), and cyan (C); A transfer roller (62) for transferring the toner image onto the intermediate transfer member (50), a cleaning device (60), and a static elimination lamp (70).
An exposure device (30) is disposed in the vicinity of the tandem developing device (120). The exposure device (30) exposes the exposure light L on the photosensitive drum (10) to form an electrostatic latent image.
Further, a secondary transfer device (22) is arranged on the opposite side of the intermediate transfer member (50) from the side where the tandem developing device (120) is arranged. The secondary transfer device (22) includes a secondary transfer belt (24), which is an endless belt stretched between a pair of rollers (23), and a recording sheet conveyed on the secondary transfer belt (24). The intermediate transfer members (50) can contact each other.
A fixing device (25) is arranged in the vicinity of the secondary transfer device (22). The fixing device (25) includes a fixing belt (26) that is an endless belt, and a pressure roller (27) that is arranged to be pressed against the fixing belt (26).
In addition, a reversing device (28) for reversing the recording paper in order to form images on both sides of the recording paper is disposed in the vicinity of the secondary transfer device (22) and the fixing device (25).

Next, full color image formation (color copying) in the image forming apparatus shown in FIG. 2 will be described. First, a document is set on the document table (130) of the automatic document feeder (ADF) (400) or the automatic document feeder (400) is opened and the document is placed on the contact glass (32) of the scanner (300). Is set and the automatic document feeder (400) is closed. Next, when a start switch (not shown) is pressed, when the document is set on the automatic document feeder (400), the document is transported and moved onto the contact glass (32), and then the contact glass ( 32) When an original is set on the scanner (300), the scanner (300) is immediately driven, and the first traveling body (33) and the second traveling body (34) travel. At this time, light from the light source is irradiated by the first traveling body (33), and reflected light from the document surface is reflected by the mirror in the second traveling body (34) and read through the imaging lens (35). Light is received by the sensor (36). Thus, a color original (color image) is read, and image information of each color of black, yellow, magenta, and cyan is obtained.
Furthermore, after the electrostatic latent image of each color is formed on the photosensitive drum (10) based on the obtained image information of each color by the exposure device (30), the electrostatic latent image of each color is developed for each color. Development is performed with the developer supplied from the container (40), and a toner image of each color is formed. The formed toner images of the respective colors are sequentially transferred (primary transfer) on the intermediate transfer body (50) that is rotated and moved by the support rollers (14), (15), and (16). ) To form a composite toner image.
In the paper feed table (200), one of the paper feed rollers (142) is selectively rotated to feed the recording paper from one of the paper feed cassettes (144) provided in multiple stages in the paper bank (143) for separation. Each sheet is separated by a roller (145), sent to a paper feed path (146), transported by a transport roller (147), guided to a paper feed path (148) in the copier body (150), and a registration roller (49 ) And stop. Alternatively, the recording paper on the manual feed tray (54) is fed out, separated one by one by the separation roller (58), put into the manual feed path (53), and abutted against the registration roller (49) and stopped. The registration roller (49) is generally used while being grounded, but may be used in a state where a bias is applied in order to remove paper dust from the recording paper.
Then, the registration roller (49) is rotated in time with the composite toner image formed on the intermediate transfer member (50), and the recording paper is placed between the intermediate transfer member (50) and the secondary transfer device (22). The composite toner image is transferred (secondary transfer) onto the recording paper.
The recording paper on which the composite toner image has been transferred is conveyed by the secondary transfer device (22) and sent out to the fixing device (25). In the fixing device (25), the composite toner image is fixed on the recording paper by being heated and pressed by the fixing belt (26) and the pressure roller (27). Thereafter, the recording paper is switched by the switching claw (55), discharged by the discharge roller (56), and stacked on the discharge tray (57). Alternatively, it is switched by the switching claw (55), reversed by the reversing device (28) and guided again to the transfer position, and after the image is formed on the back surface, it is ejected by the ejection roller (56) and ejected by the ejection tray ( 57) Stacked on top.
The toner remaining on the intermediate transfer member (50) after the composite toner image is transferred is removed by the cleaning device (17).

EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to this.
In the following, “part” means part by weight, and “%” means weight%.

-Preparation of resin fine particle dispersion-
In a reaction vessel equipped with a stirring bar and a thermometer, 683 parts of water, 11 parts of reactive emulsifier (sodium salt of sulfuric acid ester of methacrylic acid ethylene oxide adduct), Eleminol RS-30 (manufactured by Sanyo Chemical Industries), styrene 83 Parts, 83 parts of methacrylic acid, 110 parts of butyl acrylate and 1 part of ammonium persulfate were stirred at 400 rpm for 15 minutes to obtain an emulsion. The emulsion was heated, heated to 75 ° C. and reacted for 5 hours. Next, 30 parts of a 1% by weight aqueous ammonium persulfate solution was added and aged at 75 ° C. for 5 hours to prepare a resin particle dispersion.
The volume average particle size of the resin particles contained in the obtained resin particle dispersion was measured using a particle size distribution measuring apparatus Microtrac Ultra Fine Particle Size Distribution Meter UPA-EX150 (manufactured by Nikkiso Co., Ltd.) using a laser Doppler method. However, it was 45 nm. Further, a part of the resin particle dispersion was dried to isolate the resin, and the glass transition temperature of the resin was measured. As a result, it was 59 ° C. and the weight average molecular weight was 150,000.

-Unmodified polyester resin A-
Into a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen introduction tube, 67 parts of a 2-mole adduct of bisphenol A, 84 parts of a 3-mole adduct of bisphenol A, 274 parts of terephthalic acid and 2 parts of dibutyltin oxide are added. And allowed to react at 230 ° C. for 10 hours under normal pressure. Next, an unmodified polyester resin A was synthesized by reacting for 6 hours under a reduced pressure of 10 to 15 mmHg. The resulting unmodified polyester resin A has a number average molecular weight (Mn) of 2300, a weight average molecular weight (Mw) of 7,000, a glass transition temperature (Tg) of 65 ° C., an acid value of 20 mgKOH / g, and a hydroxyl value of It was 40 mgKOH / g.

-Unmodified polyester resin B-
In a reaction vessel equipped with a cooling tube, a stirrer, and a nitrogen introduction tube, 77 parts of 2-molar addition product of ethylene oxide of bisphenol A, 74 parts of 3-mole addition product of propion oxide of bisphenol A, 289 parts of terephthalic acid and 2 parts of dibutyltin oxide And allowed to react at 230 ° C. for 8 hours under normal pressure. Next, the unmodified polyester resin B was synthesized by reacting under reduced pressure of 10 to 15 mmHg for 5 hours. The resulting unmodified polyester resin B has a number average molecular weight (Mn) of 2100, a weight average molecular weight (Mw) of 5600, a glass transition temperature (Tg) of 62 ° C., an acid value of 35 mgKOH / g, and a hydroxyl value of 95 mgKOH / g.

As a measuring method of an acid value, it measured on condition of the following based on the measuring method as described in JIS K0070-1992.
Sample preparation: 0.5 g of polyester (0.3 g for ethyl acetate-soluble component) was added to 120 ml of toluene and dissolved by stirring for about 10 hours at room temperature (23 ° C.). Further, 30 ml of ethanol was added to prepare a sample solution.
The measurement can be calculated by the apparatus described above, but specifically, the calculation was performed as follows. Titration was carried out with N / 10 caustic potash-alcohol solution standardized in advance, and the acid value was determined from the consumption of alcohol potash solution by the following calculation.
Acid value = KOH (ml) x N x 56.1 / sample weight (where N is a factor of N / 10 KOH)

As a method for measuring the hydroxyl value, 0.5 g of a sample was precisely weighed into a 100 ml volumetric flask, and 5 ml of an acetylating reagent was correctly added thereto. Then, it was heated by being immersed in a bath at 100 ° C. ± 5 ° C. After 1 to 2 hours, the flask was taken out of the bath, allowed to cool, then added with water and shaken to decompose acetic anhydride. Further, in order to complete the decomposition, the flask was again heated in a bath for 10 minutes or more and allowed to cool, and then the wall of the flask was thoroughly washed with an organic solvent. This solution was subjected to potentiometric titration with an N / 2 potassium hydroxide ethyl alcohol solution using the electrode to determine the OH value (according to JISK0070-1966).

As a measuring method of the glass transition point, Rigaku THRMOFLEX TG8110 manufactured by Rigaku Denki Co., Ltd. was used. A method for measuring Tg will be outlined. As an apparatus for measuring Tg, a TG-DSC system TAS-100 manufactured by Rigaku Corporation was used. First, about 10 mg of a sample was placed in an aluminum sample container, placed on a holder unit, and set in an electric furnace. First, after heating from room temperature to 150 ° C. at a temperature rising rate of 10 ° C./min, the sample was allowed to stand at 150 ° C. for 10 min, the sample was cooled to room temperature and left for 10 min, and the temperature rising rate was again increased to 150 ° C. under a nitrogen atmosphere. DSC measurement was performed by heating at min. Tg was calculated from the contact point between the tangent line of the endothermic curve near the Tg and the base line using the analysis system in the TAS-100 system.

-Preparation of master batch-
1,000 parts of water, DBP oil absorption 42 ml / 100 g, pH 9.5 carbon black Printex 35 (Degussa) 540 parts, and 1200 parts of unmodified polyester resin A, Henschel mixer (Mitsui Mining) And mixed. Next, the obtained mixture was kneaded at 150 ° C. for 30 minutes using two rolls, then rolled and cooled, and pulverized with a pulverizer (manufactured by Hosokawa Micron Corporation) to prepare a master batch.

-Preparation of polyester prepolymer-
In a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen introduction tube, 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, 22 parts of trimellitic anhydride And 2 parts of dibutyltin oxide were added and reacted at 230 ° C. for 8 hours under normal pressure. Next, it was made to react under reduced pressure of 10-15mHg for 5 hours, and the intermediate polyester resin was synthesize | combined.
The obtained intermediate polyester resin had a number average molecular weight of 2,100, a weight average molecular weight of 9,500, a glass transition temperature of 55 ° C., an acid value of 0.5 mgKOH / g, and a hydroxyl value of 51 mgKOH / g.

Next, 410 parts of the intermediate polyester resin, 89 parts of isophorone diisocyanate, and 500 parts of ethyl acetate are charged into a reaction vessel equipped with a cooling pipe, a stirrer, and a nitrogen introduction pipe, and reacted at 100 ° C. for 5 hours. Was synthesized. The free isocyanate content of the obtained prepolymer was 1.53% by weight.

-Synthesis of ketimine-
In a reaction vessel equipped with a stir bar and a thermometer, 170 parts of isophoronediamine and 75 parts of methyl ethyl ketone were charged and reacted at 50 ° C. for 5 hours to synthesize a ketimine compound. The amine value of the obtained ketimine compound was 418 mgKOH / g.

Example 1
-Toner A1-
(Preparation of raw material solution)
In a reaction vessel equipped with a stir bar and a thermometer, 364 parts of unmodified polyester resin B, wax D (Nippon Seiwa microcrystalline wax endothermic start temperature 60 ° C., peak temperature 79 ° C.) 124 parts, and ethyl acetate 947 parts Was heated to 80 ° C. with stirring, held at 80 ° C. for 5 hours, and then cooled to 30 ° C. over 1 hour. Next, 500 parts of a master batch and 500 parts of ethyl acetate were charged into the reaction vessel and mixed for 1 hour to obtain a raw material solution.

(Preparation of wax dispersion)
1324 parts of the obtained raw material solution was transferred to a reaction vessel, and filled with 80% by volume of 0.5 mm zirconia beads using a bead mill Ultra Visco Mill (manufactured by Imex Co., Ltd.). The wax D was dispersed by passing 3 passes under the condition of a speed of 6 m / sec to obtain a wax dispersion.

(Preparation of toner material dispersion)
Next, 1324 parts of a 65 wt% ethyl acetate solution of unmodified polyester resin B was added to the wax dispersion. To 200 parts of the dispersion obtained by one pass using Ultraviscomil under the same conditions as described above, 1.5 parts of Clayton APA (manufactured by Southern Clay Products) as an organically modified layered inorganic mineral is added. . K. Using a homodisper (manufactured by Koki Kogyo Co., Ltd.), the mixture was stirred at 7000 rpm for 60 minutes to obtain a toner material dispersion.

(Production of oil phase)
In a reaction vessel, 749 parts of a toner material dispersion, 115 parts of a prepolymer and 2.9 parts of a ketimine compound are charged and mixed at 5,000 rpm for 1 minute using a TK homomixer (made by Tokushu Kika) to mix the oil phase. A liquid was obtained.

(Adjustment of aqueous medium)
990 parts of water, 83 parts of resin particle dispersion, 37 parts of 48.5% by weight aqueous solution of sodium dodecyl diphenyl ether disulfonate, Eleminol MON-7 (manufactured by Sanyo Chemical Industries), 1% by weight aqueous solution of sodium carboxymethylcellulose polymer dispersant 135 parts of BS-H-3 (Daiichi Kogyo Seiyaku Co., Ltd.) and 90 parts of ethyl acetate were mixed and stirred to obtain an aqueous medium.

(Preparation of emulsion / dispersion)
To 1200 parts of the aqueous medium, 867 parts of the oil phase mixed liquid was added and mixed for 20 minutes at 13000 rpm using a TK homomixer to prepare a dispersion (emulsified slurry).

(Solvent removal)
Next, the emulsified slurry was charged into a reaction vessel in which a stirrer and a thermometer were set, and after removing the solvent at 30 ° C. for 8 hours, aging was performed at 45 ° C. for 4 hours to obtain a dispersed slurry.
The obtained dispersion slurry was measured using Multisizer III (manufactured by Beckman Coulter, Inc.). The volume average particle size was 5.1 μm and the number average particle size was 4.9 μm.
The volume average particle size and the number average particle size were measured with a particle size measuring device (“Multisizer III”, manufactured by Beckman Coulter, Inc.) with an aperture diameter of 100 μm, and analyzed software (Beckman Coulter Multisizer 3 Version 3.51). ). Specifically, 0.5 ml of 10% by weight surfactant (alkylbenzene sulfonate, Neogen SC-A, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) is added to a 100 ml beaker made of glass, and 0.5 g of each toner is added. The mixture was stirred with a micropartel, and then 80 ml of ion-exchanged water was added. The obtained dispersion was subjected to a dispersion treatment for 10 minutes with an ultrasonic disperser (W-113MK-II, manufactured by Honda Electronics Co., Ltd.). The dispersion was measured using the Multisizer III and Isoton III (manufactured by Beckman Coulter, Inc.) as the measurement solution. In the measurement, the toner sample dispersion was dropped so that the concentration indicated by the apparatus was 8 ± 2%. In this measurement method, it is important that the concentration is 8 ± 2% from the viewpoint of the reproducibility of the particle size. Within this concentration range, no error occurs in the particle size.

(Washing)
After 100 parts by weight of the dispersion slurry was filtered under reduced pressure, 100 parts of ion-exchanged water was added to the filter cake, mixed at 12000 rpm for 10 minutes using a TK homomixer, and then filtered.
The obtained filter cake was added with 10% by weight phosphoric acid to adjust the pH to 3.7, mixed at 12000 rpm for 10 minutes using a TK homomixer, and then filtered.

(surface treatment)
Further, 300 parts of ion-exchanged water was added to the obtained filter cake, mixed for 10 minutes at 12000 rpm using a TK homomixer, and then filtered to obtain a fluorine-modified ammonium salt (manufactured by Neos; The final filter cake was obtained by adding 0.1 parts of cake to the solid content of the cake, adhering to the surface and filtering.
The obtained final filter cake was dried at 45 ° C. for 48 hours using a circulating dryer, and sieved with a mesh having a mesh size of 75 μm to obtain toner mother particles.

(Preparation of fine particles)
300 g of silica (NHM-3N manufactured by Tokuyama) having a specific surface area of 25 m ² / g and an average primary particle size of 130 nm was placed in a Henschel mixer, and stirred at about 100 ° C. at a rotation speed of 1500 rpm. 30 g of a mixed solution of propyltrimethoxysilane and toluene in a mass ratio of 1: 1 was sprayed onto the large particle size silica while atomizing with an air spray, and the surface was treated to obtain fine particles.

(External processing)
After fixing 1 part of the above-mentioned large particle size silica (average particle size 130 nm) as an external additive to 100 parts of the obtained toner base particles with a Q-type mixer (Mitsui Mining Co., Ltd.) at a processing temperature of 35 ° C., 1.0 part of hydrophobic silica (average particle size 20 nm HDK-2000) and 0.7 part of hydrophobized titanium oxide were added and mixed using a Henschel mixer (manufactured by Mitsui Mining Co., Ltd.) to obtain toner A1. .

<Example of carrier production>
The raw materials shown below were dispersed with a homomixer for 10 minutes to obtain a blend coating film forming solution of acrylic resin and silicon resin containing alumina particles. A fired ferrite powder [(MgO) 1.8 (MnO) 49.5 (Fe ₂ O ₃ ) 48.0: average particle size; 50 μm] was used as the core material, and the coating film forming solution was formed on the surface of the core material. It was applied with a Spira coater (manufactured by Okada Seiko Co., Ltd.) to a thickness of 0.15 μm and dried. The obtained carrier was baked by standing in an electric furnace at 150 ° C. for 1 hour. After cooling, the ferrite powder bulk was crushed using a sieve having an opening of 106 μm to obtain a carrier.
Acrylic resin solution (solid content 50 wt%) 21.0 parts Guanamin solution (solid content 70 wt%) 6.4 parts Alumina particles [0.3 μm, specific resistance 10 ¹⁴ (Ω · cm)] 7.6 parts Silicon resin solution [ Solid content 23wt%
(SR2410: manufactured by Toray Dow Corning Silicone Co., Ltd.)] 65.0 parts aminosilane [solid content: 100 wt%
(SH6020: manufactured by Toray Dow Corning Silicone Co., Ltd.)] 0.3 parts Toluene 60 parts Butyl cellosolve 60 parts

<Developer>
6 parts by weight of toner A1 and 94 parts by weight of the carrier were stirred for 5 minutes with a tumbler mixer (Willy A. Bachofen AG Machinenfabrik T2F) to prepare a developer.

<Toner scattering A>
The above developer was put in a Ricoh digital color imagio MP C7500 remodeled machine and evaluated.
Visual observation of toner stains scattered around the development area after 5 cycles of running output of 1000 images of 40% image area after running 5000 images of 1% image area in monochrome mode did.

◯: No scattering toner Δ: There is some scattering toner but does not stain the image ×: There is scattering toner and part of the image is stained.
XX: The amount of scattered toner is very large, and most of the image is stained.

<Toner scattering B>
The developer of the above example was put into a digital color imagio MP C7500 remodeled machine manufactured by Ricoh and evaluated.
The toner smeared around the developing portion after 50 million image area running output of 1000000 sheets in the single color mode was visually observed.

◯: No scattering toner Δ: There is some scattering toner but does not stain the image ×: There is scattering toner and part of the image is stained.
XX: The amount of scattered toner is very large, and most of the image is stained.

(Comparative Example 1)
-Toner A2-
A toner A2 was obtained in the same manner as the toner A1, except that the fluoroalkyl-treated silica was replaced with HMDS (hexamethyldisilazane) treated average particle size 130 nm silica (Tokuyama) as an external additive.
Evaluation was performed in the same manner as in Example 1 except that the developer was prepared using the toner A2.

(Comparative Example 2)
-Toner A3-
A toner A3 was obtained in the same manner as the toner A1, except that the fluoroalkyl-treated silica was not used and the hydrophobic silica (average particle size 20 nm HDK-2000) was 1.2 parts.
Evaluation was performed in the same manner as in Example 1 except that the developer was prepared using toner A3.

(Comparative Example 3)
-Toner A4-
A toner A4 was obtained in the same manner as the toner A1, except that the fluorine-modified ammonium salt was not attached to the surface of the toner base particles.
Evaluation was performed in the same manner as in Example 1 except that the developer was prepared using toner A4.

(Comparative Example 4)
-Toner A5-
Unmodified polyester resin B and zirconium salicylate (Hodogaya Chemical Co., Ltd .: TN-105) were dissolved and dispersed in an ethyl acetate solution at a ratio of 3: 1, and the dispersed particle size was 1 μm or more and the number of particles was 20% by number or less. The bead mill dispersion was carried out until it was, and a charge control agent dispersion was prepared. Toner A5 was prepared in the same manner as in Example 1 except that a toner material dispersion was prepared so that the zirconium salicylate content was 3 parts and the surface treatment was not performed with a fluorine-modified ammonium salt.

(Example 2)
-Toner A6-
A toner A6 was produced in the same manner as in Example 1 except that the particle size of the large particle size silica was 80 nm.

(Example 3)
-Toner A7-
A toner A7 was produced in the same manner as in Example 1 except that the particle diameter of the large particle diameter silica was changed to 150 nm.

Table 1 shows the evaluation results of the toners A1 to A7.

トナー飛散Ａの評価結果より、現像器へのトナー補給量が少なくなり、攪拌時間が長くなる画像面積が低い場合でも、本発明のトナーは、比較例のトナーに比較して、トナー飛散が少ないことから、メカニカルハザードを受けても適性な帯電量が得られることが分かる。
また、トナー飛散Ｂの評価結果より、現像器へのトナー補給量が多くなり、攪拌時間が短くなる画像面積が高い場合でも、本発明のトナーは、比較例のトナーに比較して、トナー飛散が少ないことから、帯電立上り性が優れ、適性な帯電量が得られることが分かる。

From the evaluation result of the toner scattering A, the toner of the present invention has less toner scattering compared to the toner of the comparative example even when the toner replenishment amount to the developing device is reduced and the stirring time is long and the image area is low. Thus, it can be seen that an appropriate charge amount can be obtained even when subjected to a mechanical hazard.
Further, from the evaluation result of the toner scattering B, even when the toner replenishment amount to the developing device is increased and the stirring area is shortened and the image area is high, the toner according to the present invention is compared with the toner of the comparative example. Therefore, it can be seen that the charge rising property is excellent and an appropriate charge amount can be obtained.

DESCRIPTION OF SYMBOLS 10 Photosensitive drum 14,15,16 Support roller 17 Cleaning apparatus 18 Image forming means 20 Charging roller 22 Secondary transfer apparatus 23 Roller 24 Secondary transfer belt 25 Fixing apparatus 26 Fixing belt 27 Pressure roller 28 Inversion apparatus 32 Contact glass 33 First traveling body 34 Second traveling body 35 Imaging lens 36 Reading sensor 42 Developer container 43 Developer supply roller 44 Developing roller 45 Developer 49 Registration roller 50 Intermediate transfer body 51 Roller 52 Corona charger 53 Manual paper feed path 54 Manual feed tray 55 Switching claw 56 Discharge roller 57 Discharge tray 58 Separating roller 60 Cleaning device 62 Transfer roller 70 Static elimination lamp 80 Transfer roller 90 Cleaning device 95 Recording paper 120 Tandem type developer 130 Document table 142 Paper feed roller 1 43 Paper Bank 144 Paper Feed Cassette 145 Separation Roller 146 Paper Feed Path 147 Transport Roller 148 Paper Feed Path 150 Copier Main Body 200 Paper Feed Table 300 Scanner 400 Automatic Document Feeder (ADF)

Japanese Patent No. 3744829 Japanese Patent Application No. 2010-165259

Claims (6)

An electrostatic charge image developing toner having toner mother particles granulated from an aqueous medium dispersion or emulsified liquid containing a toner material, and externally adding fine particles to the toner mother particles having a charge control agent on the surface. The charge control agent is a fluorine-modified ammonium salt, and the fine particles are fine particles having an average particle diameter of 80 nm or more and 150 nm or less that are surface-treated with a fluorine-based silane coupling agent. Toner for charge image development.   It contains fine particles having an average particle size of 80 nm or more and 150 nm or less that have been surface-treated with the fluorine-based silane coupling agent, in an amount of 0.5 parts by weight or more and 5 parts by weight or less with respect to 100 parts by weight of the toner base particles. The toner for developing an electrostatic charge image according to claim 1. The electrostatic charge image developing toner according to claim 1, wherein the binder resin of the toner base particles contains a polyester resin having a glass transition temperature of 30 ° C. or higher and 70 ° C. or lower. The electrostatic image developing toner according to claim 1, wherein the fine particles are silica.   5. A developer comprising the electrostatic image developing toner according to claim 1 and a carrier. An image forming apparatus comprising the electrostatic image developing toner according to claim 1.

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