JP4963378B2 - Two-component developer and developer for replenishment - Google Patents

Description

  The present invention relates to a two-component developer and a replenishment developer.

  In recent years, the development of full-color images has rapidly progressed in copying machines, printers, and the like, and development in the fields of photography, POD, and graphic arts is also expected. In the photographic field, it prints images taken with a digital camera. In the POD (print-on-demand) field, it prints the required number of copies when necessary, and images designed by CG creators called graphic arts on a PC. It is also used for printing purposes.

  When used in such applications, it is difficult to say that currently implemented full-color electrophotographic images have reached satisfactory image quality.

  In particular, in the photographic field and graphic arts field, a color reproduction range wider than the conventional color reproduction range (Japan Color) in the printing industry is required. Accordingly, studies have been made on toners having a color development exceeding the conventional color reproduction range. For example, a toner using Pigment Red 177 having a wide color reproduction range in the red region (Patent Documents 1 and 2).

  Photo printing is required to have no graininess. For this reason, the conventional two-component development method using a two-component developer is insufficient.

  Further, in the POD field, in order to print the same image in large quantities, higher durability of the developer is required. In the two-component development method, toner is consumed by development, and the carrier stays in the developing unit without being consumed and is repeatedly used.

  For this reason, carrier contamination occurs due to the toner and toner components adhering to the surface of the carrier particles. Further, the carrier itself may be stressed by being stirred in the developing device, and the coating layer of the carrier may be peeled off. As a result, the toner charge amount and transfer efficiency are lowered, and the image density and image uniformity are sometimes lowered.

  For this reason, the two-component developer using toner and ferrite carrier using Pigment Red 177 subjected to fine particle processing as described in Patent Documents 1 and 2 has a high color reproduction range that was initially achieved during mass printing. It cannot be achieved later.

  As one means for solving this problem, there has been proposed a developing device that replenishes a carrier together with the toner and gradually replaces the carrier in the developing device when replenishing toner consumed by development (patent) Reference 3). Thus, by changing the carrier little by little, a change in the charge amount of the toner is suppressed and the image density is kept stable, thereby achieving high durability.

However, when using a carrier having a specific gravity exceeding 4.2 g / cm ³ that has been used in the past, when printing about 100,000 sheets, which is expected in the POD field, the carriers rub or collide with each other in the developing machine. The impact of the image was great, carrier deterioration occurred, and image stability could not be ensured.

Japanese Patent Laid-Open No. 11-149183 JP-A-11-149184 JP 2001-330985 A

  Accordingly, an object of the present invention is to provide a two-component developer capable of achieving the color reproduction range required in the photographic field and graphic arts field, the graininess required in the photographic field, and the durability required in the POD field, and It is to provide a developer for replenishment.

As a result of intensive studies by the present inventors, in a two-component developer containing at least a toner and a carrier, the toner contains at least a binder resin, a colorant and a wax , and the spectral reflectance of the toner in a powder state is low. 380 nm to 500 nm in the range of 20% or less, 500 nm to 10 % or less, and 600 nm to 780 nm in the range of 60% or more, and the toner is in differential scanning calorimetry (DSC) measurement of the toner. The endothermic curve has one or a plurality of endothermic peaks at a temperature of 30 ° C. to 200 ° C., the peak temperature of the maximum endothermic peak is 55 to 140 ° C., the surface of the carrier is coated with a resin, and the true specific gravity is 2 by using the two-component developer which is a magnetic carrier .5 to 4.2 g / cm ^3, the photographic art graphics It found that it is possible to achieve color reproduction range required to over Tsu field, graininess required for the photographic art, and the durability required in the POD field.

  The above object can be achieved by the following configuration of the present invention.

(1) In a two-component developer containing at least a toner and a carrier,
The toner contains at least a binder resin, a colorant and a wax,
Spectral reflectance of the toner in the powder state, 20% or less in the range of 380 nm to 500nm, and 10% 500nm or less, is 60% or more in the range of 600nm to 780 nm,
The toner has one or more endothermic peaks at a temperature of 30 ° C. to 200 ° C. in the endothermic curve in the differential scanning calorimetry (DSC) measurement of the toner, and the peak temperature of the maximum endothermic peak is 55 to 140 ° C. Yes,
The two-component developer , wherein the carrier is a magnetic carrier having a resin component on the surface and a true specific gravity of 2.5 to 4.2 g / cm ³ .
(2) The volume distribution standard 50% particle size (D50) of the magnetic carrier is 15 to 70 μm, and the magnetization intensity under a magnetic field of 1000 / 4π (kA / m) is 40 to 70 Am ² / kg. (2) The two-component developer according to (1).
(3) The colorant is C.I. I. Pigment Red 3, 9, 48: 4, 104, 112, 144, 166, 168, 170, 177, 178, 220, 221, 254, C.I. I. Pigment orange 5, 34, 36, 61, 64, 67, C.I. I. Two-component developer according to any one of characterized in that it contains a pigment on one or more kinds selected from the group consisting of CI Pigment Yellow 83,139,153 (1) or (2).
(4) The two-component developer according to any one of (1) to (3), wherein the toner has an average circularity of 0.930 to 0.990.
( 5 ) Used in a two-component developing method in which a developer for replenishment containing at least toner and a carrier is developed while replenishing the developer, and the excess carrier inside the developer is discharged from the developer as needed. A developer for replenishment,
The replenishment developer, the door toner also decreased relative to the carrier 1 part by weight contained in the proportion of 2 to 50 parts by weight, the carrier has a resin component on a surface, a true specific gravity of 2.5 to 4.2 g / cm ^3, a 50% particle diameter (D50) of 15 to 70μm on a volume basis, at 1 000 / 4π (kA / m ) intensity of magnetization under a magnetic field of 40 to 70 Am ² / kg Yes,
The toner contains at least a binder resin, a colorant, and a wax , and the spectral reflectance of the toner in a powder state is 20% or less in a range of 380 nm to 500 nm, and 10 % or less at 500 nm, 600 nm to der 60% in the range of 780nm is,
The toner has one or more endothermic peaks at a temperature of 30 ° C. to 200 ° C. in the endothermic curve in the differential scanning calorimetry (DSC) measurement of the toner, and the peak temperature of the maximum endothermic peak is 55 to 140 ° C. replenishing developing agent characterized Rukoto Oh.
( 6 ) The colorant is at least C.I. I. Pigment Red 3, 9, 48: 4, 104, 112, 144, 166, 168, 170, 177, 178, 220, 221, 254, Pigment Orange 5, 34, 36, 61, 64, 67, C.I. I. ( 5 ) The developer for replenishment according to ( 5 ), which contains one or more pigments selected from the group consisting of CI Pigment Yellow 83, 139 and 153.

  According to the present invention, a two-component developer and replenishment agent that can achieve the color reproduction range required in the photographic field and graphic arts field, the graininess required in the photographic field, and the durability required in the POD field. Developers can be provided.

  The two-component developer and the replenishment developer of the present invention contain at least a toner and a carrier, and the toner contains at least a binder resin and a colorant.

  The toner used in the present invention contains at least a binder resin and a colorant, and the spectral reflectance of the toner in a powder state falls within the following range. It is 20% or less in the range of 380 to 500 nm, 15% or less at 500 nm, and 60% or more in the range of 620 to 780 nm. This schematic diagram is shown in FIG.

  More preferably, it is 20% or less in the range of 380 to 500 nm, 10% or less at 500 nm, and 60% or more in the range of 600 nm to 780 nm. More preferably, it is 20% or less in the range of 380 to 520 nm, 10% or less at 520 nm, and 60% or more in the range of 600 to 780 nm.

  If the spectral reflectance of the toner in the powder state is larger than 20% in the range of 380 to 500 nm, purple or blue light is reflected, and the color of the image after fixing becomes a color mixed with other colors, and bright red It cannot be reproduced. On the other hand, if it is less than 60% in the range of 620 to 780 nm, red light is absorbed and the color becomes dark.

  Therefore, the red color reproduction range required for the photographic field and graphic arts field can be achieved only when the spectral reflectance of the toner in the powder state falls within the above range.

As the toner binder resin, polyester; polystyrene; polymer compound obtained from styrene derivatives such as poly-p-chlorostyrene and polyvinyltoluene; styrene-p-chlorostyrene copolymer, styrene-vinyltoluene copolymer, Styrene-vinyl naphthalene copolymer, styrene-acrylic acid ester copolymer, styrene-methacrylic acid ester copolymer, styrene-α-chloromethyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-vinyl methyl ketone Styrene copolymers such as copolymers, styrene-butadiene copolymers, styrene-isoprene copolymers, styrene-acrylonitrile-indene copolymers;
Polyvinyl chloride; phenolic resin; modified phenolic resin; maleic resin; acrylic resin; methacrylic resin;
A polyester resin having as a structural unit a monomer selected from aliphatic polyhydric alcohols, aliphatic dicarboxylic acids, aromatic dicarboxylic acids, aromatic dialcohols and diphenols;
Polyurethane resin; Polyamide resin; Polyvinyl butyral; Terpene resin; Coumarone indene resin; Petroleum resin.

  The colorant used in the present invention has a spectral reflectance of the toner in a powder state of 20% or less in the range of 380 to 500 nm, 15% or less at 500 nm, and 60% or more in the range of 620 to 780 nm. Any colorant can be used.

  For example, there are colorants as shown below.

  C. I. Pigment Red 3, 9, 48: 4, 104, 112, 144, 166, 168, 170, 177, 178, 220, 221, 254, C.I. I. Pigment orange 5, 34, 36, 61, 64, 67, C.I. I. Pigment yellow 83, 139, 153, and the like. More preferably, when one or more selected from these are contained, the color reproduction range of the red region is further widened.

  A pigment may be used alone, but it is more preferable from the viewpoint of the image quality of a full-color image to improve the sharpness by using a dye and a pigment together.

  The red toner of the present invention can be used in combination with any toner such as cyan, magenta, yellow and black.

  Any colorant may be used for each toner, for example, the following colorants.

It is a coloring pigment for magenta toner, condensed azo compounds, diketopyrrolopyrrole compounds, anthraquinone, quinacridone compounds, basic dye lake compounds, naphthol compounds, benzimidazolone compounds, thioindigo compounds, Perurin compounds.

Specific examples of the color pigment for magenta toner include C.I. I. Pigment Red 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 21, 22, 23, 30, 31, 32, 37, 38, 39, 40, 41,
48: 2, 48: 3, 48: 4, 49, 50, 51, 52, 53, 54, 55, 57: 1, 58, 60, 63, 64, 68, 81: 1, 83, 87, 88, 89, 90, 112, 114, 122, 123, 144, 146, 150, 163, 166, 169,
177, 184, 185, 202, 206, 207, 209, 220, 221, 254, C.I. I. Pigment violet 19, C.I. I. Bat red 1, 2, 10, 13, 15, 23, 29, 35, etc. are mentioned.

Examples of the magenta toner dye include C.I. I solvent red 1, 3, 8, 23, 24, 25, 27, 30, 49, 81, 82, 83, 84, 100, 109, 121, C.I. I. Disper thread 9, C.I. I. Solvent Violet 8, 13, 14, 21, 27, C.I. I. Oil-soluble dyes such as Disper Violet 1;
C. I. Basic Red 1, 2, 9, 12, 13, 14, 15, 17, 18, 22, 23, 24, 27, 29, 32, 34, 35, 36, 37, 38, 39, 40, C.I. I. And basic dyes such as Basic Violet 1, 3, 7, 10, 14, 15, 21, 25, 26, 27, and 28.

Examples of the color pigment for cyan toner include C.I. I. Pigment Blue 1, 2, 3, 7, 15: 2, 15: 3, 15: 4, 16, 17, 60, 62, 66;
C. I. Bat Blue 6, C.I. I. Acid Blue 45 or a copper phthalocyanine pigment having 1 to 5 phthalimidomethyl groups substituted on the phthalocyanine skeleton.

  Examples of the color pigment for yellow toner include condensed azo compounds, isoindolinone compounds, anthraquinone compounds, azo metal compounds, methine compounds, and allylamide compounds.

  Specific examples of the color pigment for yellow toner include C.I. I. Pigment Yellow 1, 2, 3, 4, 5, 6, 7, 10, 11, 12, 13, 14, 15, 16, 17, 23, 62, 65, 73, 74, 83, 93, 95, 97, 109, 110, 111, 120, 127, 128, 129, 147, 155, 168, 174, 180, 181, 185, 191, C.I. I. Bat yellow 1, 3, 20, etc. are mentioned.

  In addition, C.I. I. Direct Green 6, C.I. I. Basic Green 4, C.I. I. Yellow toner dyes such as Basic Green 6 and Solvent Yellow 162 can also be used.

  Examples of the black colorant include carbon black, iron oxide, and those that are toned in black using the yellow / magenta / cyan colorant shown above.

  The content of the colorant is preferably 0.1 to 20 parts by mass with respect to 100 parts by mass of the binder resin for toner.

  The toner used in the present invention may contain a known charge control agent.

  In the case of a color toner, a charge control agent that is colorless or light in color, can increase the toner charging speed, and can stably maintain a constant charge amount is particularly preferable. Furthermore, in the present invention, when a toner is produced using a polymerization method, a charge control agent that does not inhibit polymerization and has no solubilized product in an aqueous medium is particularly preferable.

  Examples of the charge control agent include negative charge control agents and positive charge control agents.

  Negative charge control agents include, for example, acids such as salicylic acid, dialkylsalicylic acid, naphthoic acid, dicarboxylic acid, or metal compounds of derivatives thereof; polymer compounds having sulfonic acid or carboxylic acid in the side chain; boron compounds Urea compounds; silicon compounds; and calixarenes are preferably used.

  As the positive charge control agent, for example, a quaternary ammonium salt; a polymer compound having the quaternary ammonium salt in the side chain; a guanidine compound; and an imidazole compound are preferably used.

  The content of the charge control agent is preferably 0.5 to 10 parts by mass with respect to 100 parts by mass of the binder resin for toner. However, the addition of a charge control agent to the toner particles is not essential.

  The toner used in the present invention may contain a known wax.

  As the wax, a wax having a melting point of 55 to 140 ° C. is preferable. A low melting point wax of 55 to 120 ° C., more preferably 55 to 100 ° C. is more preferable. The low melting point wax dissolves quickly at the time of fixing, works effectively between the fixing roller and the toner interface, and has a high effect on high temperature offset.

  For this reason, application of the silicone oil to the roller, which has been conventionally performed, becomes unnecessary by including the wax. As a result, the difference in gloss between the media before printing and after printing is reduced, and an image with reduced gloss required in the graphic arts field and the POD field can be obtained.

  At the same time, color development is improved. The reason for this is not clear, but the present inventors speculate that the following occurs.

  A wax having a molecular weight close to that of the pigment, that is, a melting point of 140 ° C. or lower, preferably 120 ° C. or lower, more preferably 100 ° C. or lower has a high affinity with the pigment and, as a result, improves pigment dispersion. For this reason, the spectral reflectance of the toner in the powder state is 20% or less in the range of 380 to 500 nm, 15% or less at 500 nm, and 60% or more in the range of 620 to 780 nm. The reproduction range can be achieved.

Examples of such wax include the following. Aliphatic hydrocarbon waxes such as low molecular weight polyethylene, low molecular weight polypropylene, alkylene copolymers, microcrystalline wax, paraffin wax, Fischer-Tropsch wax,
In addition, oxides of aliphatic hydrocarbon waxes such as oxidized polyethylene wax, or block copolymers thereof;
Examples thereof include waxes mainly composed of fatty acid esters such as carnauba wax, behenic acid behenate wax, and montanic acid ester wax, and those obtained by partially or fully deoxidizing fatty acid esters such as deoxidized carnauba wax. And saturated linear fatty acids such as palmitic acid, stearic acid, and montanic acid;
Unsaturated fatty acids such as brassic acid, eleostearic acid, valinalic acid;
Saturated alcohols such as stearyl alcohol, aralkyl alcohol, behenyl alcohol, carnauvyl alcohol, seryl alcohol, melyl alcohol;
Polyhydric alcohols such as sorbitol;
Esters of fatty acids such as palmitic acid, stearic acid, behenic acid, montanic acid and alcohols such as stearyl alcohol, aralkyl alcohol, behenyl alcohol, carnauvyl alcohol, seryl alcohol, melyl alcohol;
Fatty acid amides such as linoleic acid amide, oleic acid amide, lauric acid amide;
Saturated fatty acid bisamides such as methylenebisstearic acid amide, ethylene biscapric acid amide, ethylene bislauric acid amide, hexamethylene bisstearic acid amide; ethylene bisoleic acid amide, hexamethylene bisoleic acid amide, N, N′-dio Unsaturated fatty acid amides such as rail adipic acid amide, N, N′-dioleyl sebacic acid amide;
aromatic bisamides such as m-xylenebisstearic acid amide and N, N′-distearylisophthalic acid amide;
Aliphatic metal salts such as calcium stearate, calcium laurate, zinc stearate, magnesium stearate (commonly referred to as metal soap);
Waxes grafted to aliphatic hydrocarbon waxes using vinyl monomers such as styrene and acrylic acid;
Examples include partially esterified products of fatty acids such as behenic acid monoglyceride and polyhydric alcohols; methyl ester compounds having a hydroxyl group obtained by hydrogenation of vegetable oils and the like.

  Examples of the wax preferably used in the present invention include aliphatic hydrocarbon waxes and ester waxes that are esters of fatty acids and alcohols. For example, low molecular weight alkylene polymer obtained by radical polymerization of alkylene under high pressure or Ziegler catalyst or metallocene catalyst under low pressure; alkylene polymer obtained by thermal decomposition of high molecular weight alkylene polymer; synthesis containing carbon monoxide and hydrogen A synthetic hydrocarbon wax obtained from the distillation residue of hydrocarbons obtained from the gas by the age method or by hydrogenating them is preferred. Furthermore, what carried out the fractionation of the hydrocarbon wax by the use of the press perspiration method, the solvent method, the vacuum distillation, or the fractional crystallization method is more preferably used. The hydrocarbon as a base is synthesized by the reaction of carbon monoxide and hydrogen using a metal oxide catalyst (mostly two or more multi-component systems) [for example, the Jintol method, the Hydrocol method (the fluidized catalyst bed Hydrocarbon compounds synthesized by use); hydrocarbons with up to several hundred carbon atoms obtained by the age method (using the identified catalyst bed) from which a large amount of wax-like hydrocarbons can be obtained; alkylene such as ethylene by Ziegler catalyst Polymerized hydrocarbons are preferred because they are linear hydrocarbons with little branching, small and long saturation. In particular, a wax synthesized by a method that does not rely on polymerization of alkylene is also preferred from its molecular weight distribution.

  Among them, an aliphatic hydrocarbon wax having a melting point of 55 to 100 ° C. or an ester wax that is an ester of alcohol can improve color development particularly effectively.

  The reason for this is not clear, but paraffin wax is effective because it binds to the pigment effectively because the aromatic ring of the pigment and the ester bond of the ester wax are close to the carbonyl group of the pigment. The inventors are thinking.

  The charge control agent and the release agent can be melt kneaded together with the master batch and the binder resin, or of course, may be added when dissolved and dispersed in the organic solvent.

  The toner used in the present invention may contain a fluidizing agent. Any fluidizing agent can be used as long as it can increase fluidity before and after the fluidizing agent is added to the toner.

  Examples of the fluidizing agent include fluorine resin powders such as vinylidene fluoride fine powder and polytetrafluoroethylene fine powder; titanium oxide fine powder; alumina fine powder; fine powder silica such as wet process silica and dry process silica; fluorine Examples thereof include treated silica obtained by subjecting a system resin powder, titanium oxide fine powder, alumina fine powder and fine powder silica to surface treatment with a silane compound, an organosilicon compound, a titanium coupling agent, silicone oil, and the like.

A preferred dry process silica is a fine powder produced by vapor phase oxidation of a silicon halogen compound, which is called so-called dry process silica or fumed silica, and is produced by a conventionally known technique. As the dry process silica, for example, a thermal decomposition oxidation reaction in an oxyhydrogen flame of silicon tetrachloride gas is used. The basic reaction formula is the following formula (1).
(1): SiCl ₄ + 2H ₂ + O ₂ → SiO ₂ + 4HCl

  In this production process, it is also possible to obtain a composite fine powder of silica and another metal oxide by using another metal halogen compound such as aluminum chloride or titanium chloride together with a silicon halogen compound. Also includes them.

  The particle diameter of the dry process silica is preferably in the range of 0.001 to 2 μm as an average primary particle diameter, and particularly preferably silica fine powder in the range of 0.002 to 0.2 μm is used. Is good.

Examples of the titanium oxide fine powder include fine particles of titanium oxide obtained by low-temperature oxidation (thermal decomposition, hydrolysis) of sulfuric acid method, chlorine method, volatile titanium compounds such as titanium alkoxide, titanium halide, and titanium acetylacetonate. Is included. Crystalline titanium oxide fine as a powder anatase, rutile, these mixed crystal, include acid titanium fine powder of amorphous.

  Examples of the alumina fine powder include a buyer method, an improved buyer method, an ethylene chlorohydrin method, an underwater spark discharge method, an organoaluminum hydrolysis method, an aluminum alum pyrolysis method, an ammonium aluminum carbonate pyrolysis method, a chlorination method. Alumina fine powder obtained by the flame decomposition method of aluminum is included. Examples of the crystalline alumina fine powder include α, β, γ, δ, ξ, η, θ, κ, χ, ρ type, mixed crystal type and amorphous alumina fine powders. Α, δ, γ , Θ, mixed crystal type, amorphous alumina fine powder is preferably used.

  More preferably, the surface of the fine powder is subjected to a hydrophobic treatment. Or it may be oil-treated.

  The method of hydrophobizing the surface of the fine powder is a method of chemically or physically treating with an organosilicon compound that reacts or physically adsorbs with the fine powder.

  A preferable method for the hydrophobic treatment is a method in which silica fine particles produced by vapor phase oxidation of a silicon halogen compound are treated with an organosilicon compound.

  Examples of the organosilicon compound include hexamethyldisilazane, trimethylsilane, trimethylchlorosilane, trimethylethoxysilane, dimethyldichlorosilane, methyltrichlorosilane, allyldimethylchlorosilane, allylphenyldichlorosilane, benzyldimethylchlorosilane, Brommethyldimethylchlorosilane, α-chloroethyltrichlorosilane, β-chloroethyltrichlorosilane, chloromethyldimethylchlorosilane, triorganosilylmercaptan, trimethylsilylmercaptan, triorganosilylacrylate, vinyldimethylacetoxysilane, dimethylethoxysilane, dimethyldimethoxy Silane, diphenyldiethoxysilane, hexamethyldisiloxane, 1,3-divinyltetramethyldisiloxane, 1 , 3-diphenyltetramethyldisiloxane, and dimethylpolysiloxane having 2 to 12 siloxane units per molecule and having one hydroxyl group each in the terminal unit of Si. These are used alone or in a mixture of two or more.

  The content of the fine powder is preferably 0.8 to 8.0 parts by mass, and more preferably 1.0 to 4.0 parts by mass with respect to 100 parts by mass of the toner particles.

The fluidizing agent used in the present invention has a specific surface area by nitrogen adsorption measured by BET method of 30 m ² / g or more, preferably 50 m ² / g or more from the viewpoint of fluidity imparting property.

  Further, the preferable content of the fluidizing agent is 0.01 to 8 parts by mass, more preferably 0.1 to 4 parts by mass with respect to 100 parts by mass of the toner particles.

(Production method)
As a method for producing toner particles,
1) pulverization method 2) suspension polymerization method 3) emulsion aggregation method 4) ester elongation polymerization method 5) dispersion polymerization method 6) emulsion polymerization method and the like.

1) Pulverization method A toner production procedure in the pulverization method will be described.

  In the raw material mixing step in the pulverization method, at least a binder resin, a colorant, and, if necessary, raw materials such as a release agent are weighed and mixed as a toner internal additive and mixed. Examples of the mixing device include a double-con mixer, a V-type mixer, a drum-type mixer, a super mixer, a Henschel mixer, and a Nauter mixer.

  Further, the toner raw materials blended and mixed as described above are melt-kneaded to melt the binder resin, and a colorant or the like is dispersed therein to obtain a colored resin composition. In the melt-kneading step, for example, a batch kneader such as a pressure kneader or a Banbury mixer, or a continuous kneader can be used. In recent years, single-screw or twin-screw extruders have become mainstream due to the advantage of being capable of continuous production. For example, KTK type twin screw extruder manufactured by Kobe Steel, TEM type twin screw extruder manufactured by Toshiba Machine Co., Ltd. In general, a twin-screw extruder manufactured by Kay Sea Kay, a co-kneader manufactured by Buss, or the like is used. Furthermore, the colored resin composition obtained by melt-kneading the toner raw material is rolled by a two-roll roll after melt-kneading, and then cooled through a cooling step of cooling by water cooling or the like.

  In general, the cooled colored resin composition obtained above is then pulverized to a desired particle size in a pulverization step. In the pulverization step, first, coarse pulverization is performed with a crusher, a hammer mill, a feather mill or the like, and further, pulverization is performed with a kryptron system manufactured by Kawasaki Heavy Industries, Ltd., a super rotor manufactured by Nisshin Engineering Co., Ltd. or the like. After that, if necessary, classification is performed using a classifier such as an inertia class elbow jet (manufactured by Nippon Steel & Mining Co., Ltd.), centrifugal class turbo plex (manufactured by Hosokawa Micron Co., Ltd.), and the weight average particle size A classified product of 3 to 11 μm is obtained.

  If necessary, it is possible to perform spheronization treatment as surface modification in the surface modification step. For example, the spheronization treatment may be performed using a hybridization system manufactured by Nara Machinery Co., Ltd. or a mechano-fusion system manufactured by Hosokawa Micron Co., Ltd., to obtain a classified product.

(Polymerization method)
When toner particles are produced by a polymerization method, 2,2′azobis- (2,4-dimethylvaleronitrile), 2,2′-azobisisobutyronitrile, 1,1′- is used as a polymerization initiator. Azobis (an azo polymerization initiator such as cyclohexane-1-carbonitrile, 2,2′-azobis-4-methoxy-2,4-dimethylvaleronitrile, azobisisobutyronitrile;
Peroxide-based polymerization initiators such as benzoyl peroxide, methyl ethyl ketone peroxide, diisopropyl peroxycarbonate, cumene hydroperoxide, 2,4-dichlorobenzoyl peroxide, lauroyl peroxide are used.

  The addition amount of the polymerization initiator varies depending on the desired degree of polymerization, but generally 0.5 to 20% by mass is added to the polymerizable monomer. Although the polymerization initiator varies slightly depending on the polymerization method, the polymerization initiator is used alone or in combination with reference to the 10-hour half-life temperature. It is also possible to add and use a known crosslinking agent, chain transfer agent, polymerization inhibitor, etc. for controlling the degree of polymerization.

  When suspension polymerization is used as a toner production method, a dispersant may be used. Examples of the dispersant used include inorganic compounds and organic compounds.

  Inorganic compounds include tricalcium phosphate, magnesium phosphate, aluminum phosphate, zinc phosphate, calcium carbonate, magnesium carbonate, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, calcium metasilicate, calcium sulfate, barium sulfate , Bentonite, silica, alumina and the like.

  Examples of the organic compound include polyvinyl alcohol, gelatin, methyl cellulose, methyl hydroxypropyl cellulose, ethyl cellulose, sodium salt of carboxymethyl cellulose, starch and the like.

  These dispersants are used by being dispersed in an aqueous phase. A preferable blending amount of these dispersants is 0.2 to 10.0 parts by mass with respect to 100 parts by mass of the polymerizable monomer.

  Commercially available dispersants may be used as they are, but in order to obtain dispersed particles having a fine uniform particle size, the inorganic compound can be produced in a dispersion medium under high-speed stirring. For example, in the case of tricalcium phosphate, a preferable dispersant can be obtained by suspension polymerization by mixing an aqueous sodium phosphate solution and an aqueous calcium chloride solution under high-speed stirring.

  In order to make these dispersants finer, 0.001 to 0.1 parts by mass of a surfactant may be used in combination with 100 parts by mass of the polymerizable monomer. As the surfactant, commercially available nonionic, anionic or cationic surfactants can be used. For example, sodium dodecyl sulfate, sodium tetradecyl sulfate, sodium pendadecyl sulfate, sodium octyl sulfate, sodium oleate, sodium laurate, stearin Potassium acid and calcium oleate are preferably used.

2) Suspension polymerization method When the suspension polymerization method is used, the toner can be specifically manufactured by the following manufacturing method.

  Add a release agent, colorant, charge control agent, polymerization initiator and other additives consisting of a low softening substance into the monomer, and dissolve or disperse it uniformly with a homogenizer, ultrasonic disperser, etc. Get things. The obtained monomer composition is dispersed in an aqueous phase containing a dispersion stabilizer by a usual stirrer, homomixer, homogenizer or the like. Preferably, the droplets made of the monomer composition are granulated by adjusting the stirring speed and time so as to have a desired toner particle size. Thereafter, stirring may be performed to such an extent that the particle state is maintained and the sedimentation of the particles is prevented by the action of the dispersion stabilizer. The polymerization is carried out at a polymerization temperature of 40 ° C. or higher, generally 50 to 90 ° C. The temperature may be raised in the latter half of the polymerization reaction, and for the purpose of improving the durability, a part of the aqueous medium is retained after the latter half of the reaction or after the completion of the reaction in order to remove unreacted polymerizable monomers and byproducts. You may leave. After completion of the reaction, the produced toner particles are recovered by washing and filtration and dried. In the direct polymerization method, it is usually preferable to use 300 to 3000 parts by weight of water as a dispersion medium with respect to 100 parts by weight of the monomer composition.

3) Emulsion aggregation method Obtained through a toner production method through at least a step of aggregating polymer fine particles and colorant fine particles to form a fine particle aggregate and a ripening step of causing fusion between the fine particles in the fine particle aggregate. In the case of using the emulsion aggregation method, the toner can be manufactured by the following manufacturing method.

  The polymer fine particles used in the emulsion aggregation method may be fine particles emulsified and dispersed in an aqueous solvent, such as fine emulsion particles obtained by emulsion polymerization of a known polymerizable monomer, or emulsification in which the above polymer is dissolved. Fine particles are preferably used.

  The average particle diameter of these emulsified fine particles is preferably 0.05 to 3 μm, more preferably 0.1 to 1 μm, and particularly preferably 0.1 to 0.5 μm. The average particle diameter can be measured using a fine particle measuring apparatus (for example, UPA manufactured by Microtrac). If the particle size is smaller than 0.05 μm, it is difficult to control the aggregation rate, which is not preferable. On the other hand, if the particle size is larger than 3 μm, the particle size of the toner obtained by agglomeration becomes too large, so that it is unsuitable for applications requiring a high granular feeling as a toner.

  These emulsified fine particles can be agglomerated by adding an aggregating agent such as an electrolyte to the emulsified dispersion with stirring, if necessary, and further heating to form fine particle aggregates.

The electrolyte used may be either an organic salt or an inorganic salt, but a monovalent or divalent or higher polyvalent metal salt is preferably used. Specific examples of such salts include NaCl, KCl, LiCl, Na ₂ SO ₄ , K ₂ SO ₄ , Li ₂ SO ₄ , MgCl ₂ , CaCl ₂ , MgSO ₄ , CaSO ₄ , ZnSO ₄ , Al ₂ (SO ₄ ) ₃ , Fe ₂ (SO ₄ ) _{3 and the} like.

  In adding the electrolyte, the temperature of the mixed dispersion is preferably kept at 40 ° C. or lower. When an electrolyte is added under conditions where the temperature exceeds 40 ° C., rapid aggregation occurs, and particle size control becomes difficult, and the bulk density of the obtained particles may be low.

  Thereafter, the mixture is heated to produce aggregated particles. The aggregated particle formation temperature may be any temperature according to the aggregated form of the particles. Stirring may be performed in a reaction tank having a normal known stirring device such as a paddle blade, squid blade, three retreat blades, Max blend blade, full zone blade, double helical, etc., homogenizer, homomixer, Henschel mixer, etc. Can also be used.

  The particle size growth by the aggregation process is carried out until particles having substantially the same size as the toner particles are obtained, but can be controlled relatively easily by adjusting the pH and temperature of the dispersion. The pH value varies depending on the type and amount of emulsifier used and the target particle size of the toner, so it cannot be uniquely defined. However, when an anionic surfactant is mainly used, the pH is usually 2 to 6, and the cationic surface activity. When an agent is used, a pH of about 8 to 12 is usually used.

  Next, the aging process will be described.

  The toner used in the replenishment developer of the present invention can be obtained through a aging step for causing fusion between the fine particles in the fine particle aggregate after the step of forming the fine particle aggregate.

  In order to increase the stability of the fine particle aggregate obtained in the aggregation step, the fine particle aggregate is held for a predetermined time at a temperature higher than the glass transition temperature (Tg) of the polymer primary particle, thereby fusing the aggregated particles. Wake up. The aging step can be performed using a stirrer similar to the stirrer used in the aggregation step.

  The toner particles obtained through each of the above steps are obtained by solid-liquid separation according to a known method, collecting the toner particles, and then washing and drying the toner particles as necessary.

  These toners may be classified to control the particle size distribution, and as a method therefor, a multi-division classifier using inertial force is preferably used. By using this apparatus, a toner having a preferable particle size distribution in the present invention can be efficiently produced.

4) Ester extension polymerization In the case of using ester extension polymerization, it is possible to specifically manufacture the toner by the following manufacturing method.

  A) A toner material liquid is prepared by dispersing a colorant, unmodified polyester, a polyester prepolymer having an isocyanate group, and a release agent in an organic solvent.

The organic solvent is preferably volatile with a boiling point of less than 100 ° C. from the viewpoint of easy removal after toner base particle formation. 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, Methyl isobutyl ketone and the like can be used alone or in combination of two or more. In particular, aromatic solvents such as toluene and xylene and halogenated hydrocarbons such as methylene chloride, 1,2-dichloroethane, chloroform, and carbon tetrachloride are preferable. The amount of the organic solvent, relative to 100 mass parts polyester prepolymer, generally from 0 to 300 parts by weight, preferably from 0 to 100 parts by weight, more preferably 25 to 70 parts by weight.

B) The toner material liquid is emulsified in an aqueous medium in the presence of a surfactant and resin fine particles.
The aqueous medium may be water alone or an organic solvent such as alcohol (methanol, isopropyl alcohol, ethylene glycol, etc.), dimethylformamide, tetrahydrofuran, cellosolves (methyl cellosolve, etc.), lower ketones (acetone, methyl ethyl ketone, etc.). It may be included.

The amount of the aqueous medium used with respect to 100 parts by mass of the toner material liquid 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 material liquid is poor, and toner particles having a predetermined particle diameter cannot be obtained. More than 20,000 mass part is not economical.

  Further, in order to improve the dispersion in the aqueous medium, a dispersant such as a surfactant and resin fine particles is appropriately added.

  The resin fine particles are added to stabilize the toner base particles formed in the aqueous medium. For this reason, it is preferable to add so that the coverage existing on the surface of the toner base particles is 10 to 90%. For example, polymethyl methacrylate fine particles 1 μm and 3 μm, polystyrene fine particles 0.5 μm and 2 μm, poly (styrene-acrylonitrile) fine particles 1 μm, trade names are PB-200H (manufactured by Kao Corporation), SGP (manufactured by Soken Co., Ltd.), Techno Examples include polymer SB (manufactured by Sekisui Chemical Co., Ltd.), SGP-3G (manufactured by Sokensha), and micropearl (manufactured by Sekisui Fine Chemical Co., Ltd.)

  In addition, inorganic compound dispersants such as tricalcium phosphate, calcium carbonate, titanium oxide, colloidal silica, and hydroxyapatite can also be used.

  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. Among these, the high-speed shearing method is preferable in order to make the particle size of the dispersion 2 to 20 μm. When a high-speed shearing disperser is used, the rotation speed is not particularly limited, but is usually 1000 to 30000 rpm, preferably 5000 to 20000 rpm. The dispersion time is not particularly limited, but in the case of a batch method, it is usually 0.1 to 5 minutes. The temperature during dispersion is usually 0 to 150 ° C. (under pressure), preferably 40 to 98 ° C.

  C) At the same time as the preparation of the emulsion, the amines (B) are added to react with the polyester prepolymer (A) having an isocyanate group.

  This reaction involves molecular chain crosslinking and / or elongation. The reaction time is selected depending on the reactivity between the isocyanate group structure of the polyester prepolymer (A) and the amines (B), but is usually 10 minutes to 40 hours, preferably 2 to 24 hours.

  The reaction temperature is usually 0 to 150 ° C., preferably 40 to 98 ° C. Moreover, a well-known catalyst can be used as needed. Specific examples include dibutyltin laurate and dioctyltin laurate.

  D) After completion of the reaction, the organic solvent is removed from the emulsified dispersion (reactant), washed and dried to obtain toner base particles.

  In order to remove the organic solvent, the temperature of the entire system is gradually raised in a laminar stirring state, and after giving strong stirring in a certain temperature range, the solvent-based toner base particles can be produced by removing the solvent. . Further, when an acid such as calcium phosphate salt or an alkali-soluble material is used as the dispersion stabilizer, the calcium phosphate salt is dissolved from the toner base particles by a method such as dissolving the calcium phosphate salt with an acid such as hydrochloric acid and washing with water. Remove. It can also be removed by operations such as enzymatic degradation.

  E) A charge control agent is injected into the toner base particles obtained above, and then inorganic fine particles such as silica fine particles and titanium oxide fine particles are externally added to obtain a toner.

  The injection of the charge control agent and the external addition of the inorganic fine particles are performed by a known method using a mixer or the like.

  Thereby, a toner having a small particle size and a sharp particle size distribution can be easily obtained. Furthermore, by giving strong agitation in the process of removing the organic solvent, the shape between the spherical shape and the spindle shape can be controlled, and the surface morphology is also controlled between the smooth shape and the umeboshi shape. Can do.

As other manufacturing methods,
5) Dispersion polymerization method Monomer that is soluble in a monomer but insoluble when a polymer is formed and an aqueous organic solvent are used to directly produce toner particles 6) Emulsion polymerization method, water-soluble polar polymerization started Toner particles can be produced using direct polymerization in the presence of an agent to produce toner particles.

  The toner used in the present invention preferably has a weight average particle diameter (D4) of 3.0 to 11.0 μm. A more preferred weight average particle diameter is 4.5 to 9.0 μm. When the weight average particle diameter (D4) of the toner is within this range, an image with good dot reproducibility can be obtained.

  When the weight average particle diameter (D4) of the toner is less than 3.0 μm, the specific surface area of the toner is increased, and the surface existing amount on the carrier in the replenishment developer is increased. As a result, when replenished into the developing device, the mixing property with the carrier in the developing device is deteriorated and the uniformity is deteriorated. On the other hand, when the weight average particle diameter (D4) of the toner exceeds 11.0 μm, the dot reproducibility is deteriorated and high image quality cannot be achieved.

  In addition, it is preferable that the average circularity of particles having an equivalent circle diameter (number basis) of 2.0 μm or more of the toner is 0.930 to 0.990 in order to achieve both transferability and developability.

When the average circularity of the toner is lower than 0.930, the image density may decrease due to a decrease in transfer efficiency after endurance, and image unevenness may occur due to toner shape non-uniformity during development. When the average circularity of the toner is higher than 0.990, because of the spherical shape, the toner moves on the transfer belt or paper at the time of transfer / fixing, and the image is disturbed.

  Methods for measuring the weight average particle diameter, equivalent circle diameter, and average circularity will be described later.

(Career)
The two-component developer and the replenishment developer of the present invention contain at least a toner and a carrier, and the carrier is a magnetic carrier having a resin component on the surface and a true specific gravity of 2.5 to 4.2 g / cm ^3. is there.

The carrier of the present invention is not particularly limited as long as it is the magnetic carrier. For example,
(1) A magnetic substance-containing resin carrier containing a resin component on the surface of a magnetic substance-containing resin carrier core in which the magnetic substance is dispersed in the resin. (2) A resin is impregnated with a porous magnetic substance (including porous ferrite). And so-called resin-impregnated carriers.

  (1) The magnetic substance-containing resin carrier will be described.

  As a method for producing the core of the magnetic substance-containing resin carrier, there is a method obtained by polymerizing monomers constituting the resin in the presence of the magnetic substance.

  At this time, as monomers used for polymerization, in addition to vinyl monomers, bisphenols and epichlorohydrin for forming epoxy resins; phenols and aldehydes for forming phenol resins; urea resins are formed Urea and aldehydes for forming; melamine and aldehydes for forming melamine resin are used.

  Phenol resin is preferable as the resin for forming the magnetic substance-containing resin carrier used in the present invention. As phenols for producing the phenol resin, m-cresol, p-tert-butylphenol, o-, in addition to phenol, are used. Examples thereof include compounds having a phenolic hydroxyl group such as alkylphenols such as propylphenol, resorcinol, and bisphenol A, and halogenated phenols in which a benzene nucleus or alkyl group is partially or entirely substituted with a chlorine atom or a bromine atom. Of these, phenol (hydroxybenzene) is more preferable.

  Examples of aldehydes for producing the phenol resin include formaldehyde and furfural in the form of either formalin or paraaldehyde. Of these, formaldehyde is particularly preferable.

  The molar ratio of aldehydes to phenols is preferably 1 to 4, particularly preferably 1.2 to 3. When the molar ratio of aldehydes to phenols is less than 1, particles are difficult to generate, or even if they are generated, the resin does not easily cure, so the strength of the particles generated tends to be weak. On the other hand, when the molar ratio of aldehydes to phenols is larger than 4, unreacted aldehydes remaining in the aqueous medium after the reaction tend to increase.

  Examples of the basic catalyst used for polycondensation of phenols and aldehydes include those used in the production of ordinary resol type resins. Examples of such basic catalysts include aqueous ammonia, hexamethylenetetramine, and alkylamines such as dimethylamine, diethyltriamine, and polyethyleneimine. The molar ratio of these basic catalysts to phenols is preferably 0.02 to 0.30.

In the magnetic substance-containing resin carrier core, the magnetic substance is preferably magnetite fine particles or magnetic ferrite fine particles containing at least an iron element. Further, in order to adjust the magnetic properties of the carrier, a part of the magnetic material contained in the magnetic material-containing resin carrier may be replaced with a nonmagnetic inorganic compound. It is more preferable that the nonmagnetic inorganic compound is hematite (α-Fe ₂ O ₃ ) fine particles in order to make the dispersibility in the carrier uniform and adjust the magnetic properties and true specific gravity of the carrier. A nonmagnetic inorganic compound has a specific resistance value larger than that of a magnetic substance.

  The number average particle size of the magnetic material is preferably 0.02 to 2 μm from the viewpoint of making the state of the carrier particle surface uniform. The nonmagnetic inorganic compound preferably has a number average particle diameter of 0.05 to 5 μm, and the nonmagnetic inorganic compound has a particle diameter of 1.1 times or more larger than that of the magnetic substance. It is preferable for increasing the surface resistance value.

  The amount of the magnetic material used for the magnetic substance-containing resin carrier core is 70 to 95% by mass (more preferably 80 to 92% by mass) with respect to the magnetic substance-containing resin carrier core. It is preferable for reducing the specific gravity and ensuring sufficient mechanical strength.

  Further, the magnetic substance is contained in an amount of 30 to 99% by mass with respect to the total amount of the magnetic substance and the nonmagnetic inorganic compound in the magnetic substance-containing resin carrier core. It is preferable to adjust to prevent carrier adhesion and to adjust the specific resistance value of the magnetic substance-containing resin carrier core.

  As a method for producing a magnetic substance-containing resin carrier core using a phenol resin, for example, in an aqueous medium containing phenols, aldehydes, and a magnetic substance, phenols and aldehydes are polymerized in the presence of a basic catalyst. Thus, a magnetic substance-containing resin carrier core can be obtained. When a magnetic substance-containing resin carrier core is manufactured by this method, the average circularity is easily adjusted to the above range, and this method is a preferable manufacturing method.

  As another method for manufacturing the above-mentioned magnetic material-containing resin carrier core, a vinyl-based or non-vinyl-based thermoplastic resin, a magnetic material, and other additives are sufficiently mixed by a mixer, and then heated rolls, kneaders, extensibles. There is a method in which a magnetic material-containing resin carrier core is obtained by melting and kneading using a kneader such as a ruder, cooling this, and then crushing and classifying. At this time, it is preferable to thermally or mechanically spheroidize the obtained magnetic substance-containing resin carrier core and use it as a magnetic substance-containing resin carrier core.

  The surface of the carrier core is preferably coated with a coating resin from the viewpoint of imparting charge to the toner and releasability. As the coating resin, an insulating resin is preferably used. The insulating resin that can be used in this case may be a thermoplastic resin or a thermosetting resin.

Examples of thermoplastic resins include: polystyrene; acrylic resins such as polymethyl methacrylate and styrene-acrylic acid copolymers; styrene-butadiene copolymers; ethylene-vinyl acetate copolymers; polyvinyl chloride;
Polyvinylidene fluoride resin; fluorocarbon resin; perfluorocarbon resin; solvent-soluble perfluorocarbon resin; polyvinyl alcohol; polyvinyl acetal; polyvinylpyrrolidone;
Cellulose derivatives such as cellulose, cellulose acetate, cellulose nitrate, methylcellulose, hydroxymethylcellulose, hydroxymethylcellulose, hydroxypropylcellulose;
Low molecular weight polyethylene; saturated alkyl polyester resin; aromatic polyester resin such as polyethylene terephthalate, polybutylene terephthalate, polyarylate;
Polyamide resin; Polyacetal resin; Polycarbonate resin; Polyethersulfone resin; Polysulfone resin; Polyphenylene sulfide resin;

Examples of thermosetting resins include phenolic resins, modified phenolic resins, maleic resins, alkyd resins, epoxy resins, acrylic resins, unsaturated polyesters obtained by polycondensation of maleic anhydride, terephthalic acid and polyhydric alcohols,
Urea resin, melamine resin, urea-melamine resin, xylene resin, toluene resin, guanamine resin, melamine-guanamine resin, acetoguanamine resin, gliptal resin, furan resin, silicone resin, polyimide, polyamideimide resin, polyetherimide resin, polyurethane Resin.

  The above-mentioned resins can be used alone or in combination. In addition, a curing agent or the like can be mixed with a thermoplastic resin and cured for use. As a particularly preferable form, it is preferable to use a resin having a higher release property for a toner having a small particle diameter and containing a release agent.

  Furthermore, the coat resin may contain particles having conductivity and particles having charge controllability. Such a coating resin is preferably coated on the carrier core by an appropriate method, either alone or by adding conductive particles or charge controllable particles to the monomer forming the resin. These particles are preferably contained from the viewpoint of providing a soft and quick charge to a toner having a small particle size and having a low-temperature fixability.

The conductive particles preferably have a specific resistance of 1 × 10 ⁸ Ωcm or less, and more preferably have a specific resistance of 1 × 10 ⁶ Ωcm or less. Specifically, the conductive particles are preferably particles containing at least one kind of particles selected from carbon black, magnetite, graphite, zinc oxide, and tin oxide. In particular, as the particles having conductivity, carbon black having good conductivity is preferable in terms of improving the charge imparting property (rise of charge amount) to the toner.

  It is preferable that the conductive particles have a number average particle size of 1 μm or less in order to prevent the particles from falling off from the carrier and to function as a uniform conductive site.

  The particles having charge controllability include organometallic complex particles, organometallic salt particles, chelate compound particles, monoazo metal complex particles, acetylacetone metal complex particles, hydroxycarboxylic acid metal complex particles, and polycarboxylic acid. Examples include metal complex particles and polyol metal complex particles. A charge control agent dispersed in the toner particles may be used, but use of resin particles having a functional group or inorganic particles treated with a treatment agent having a functional group improves the charge imparting property to the toner. It is preferable for this purpose.

Specifically , the particles having charge controllability include polymethyl methacrylate resin particles, polystyrene resin particles, melamine resin particles, phenol resin particles, nylon resin particles, silica particles, titanium oxide particles, and The particles preferably contain at least one kind of particles selected from alumina particles. Further, in the case of inorganic particles, it is preferable to use them after being treated with various coupling agents in order to develop charge controllability and conductivity.

  The particles having charge control properties preferably have a number average particle diameter of 0.01 to 1.50 μm from the viewpoint of functioning as a uniform charging site.

  The coating amount of the coating resin on the carrier core is 0.1 to 5.0 parts by mass with respect to 100 parts by mass of the carrier core, thereby improving the charge imparting property to the toner and the durability of the magnetic carrier. Preferred above. The blending amount of the conductive particles and the charge controllable particles is preferably 0.1 to 30 parts by mass in total with respect to 100 parts by mass of the coating resin.

  When the conductive particles or the charge controllable particles are added in an amount exceeding 30 parts by mass, the particles are difficult to disperse in the coating resin, and the particles may be detached from the magnetic carrier. In particular, when carbon black is added, the toner may be contaminated with carbon black or the member may be contaminated as the durability increases.

  (2) The resin-impregnated carrier will be described.

  The core of the resin-impregnated carrier is manufactured using a porous magnetic material. Examples of porous magnetic materials include Ca—Mg—Fe ferrite, Li—Fe ferrite, Mn—Mg—Fe ferrite, Ca—Be—Fe ferrite, Mn—Mg—Sr—Fe ferrite, Li -Ferrite magnetic bodies of iron-based oxides such as -Mg-Fe-based ferrite and Li-Rb-Fe-based ferrite are included. Ferrites of iron-based oxides can be obtained by mixing metal oxides, carbonates, nitrates, and the like in a wet or dry manner and calcining to obtain a desired ferrite composition. The obtained iron oxide ferrite is pulverized to submicron. To the pulverized ferrite, 20 to 50% by mass of water for adjusting the particle diameter is added to the ferrite, and 0.1 to 10% by mass of polyvinyl alcohol (molecular weight 500 to 10,000) is added as a binder, for example. A slurry is prepared by adding 0.5 to 15% by mass of a metal carbonate such as calcium carbonate for controlling the density.

  The slurry can be granulated using a spray dryer or the like to obtain a porous magnetic material. Here, the particle size of the porous magnetic material can be controlled by appropriately adjusting the viscosity of the slurry and the size of the nozzle of the spray dryer.

  A resin-impregnated carrier can be produced by impregnating the core of the resin-impregnated carrier thus produced with a coat resin. Any coating resin may be used. For example, the resin used in the magnetic substance-containing resin carrier can be used.

  The carrier used for the two-component developer and the replenishment developer of the present invention has a 50% particle size (D50) of 15 to 70 μm based on volume distribution. The thickness is preferably 20 to 70 μm, more preferably 25 to 60 μm. When the 50% particle size (D50) based on the volume distribution of the magnetic carrier is within this range, an image with good dot reproducibility can be obtained over a long period of time without fogging. When the 50% particle size (D50) based on the volume distribution of the carrier is less than 15 μm, the fluidity of the carrier is reduced, and fine powders are likely to accumulate, and uniform carrier recovery may not be performed satisfactorily. When it exceeds 70 μm, the carrier particle size is large, so that the density of the magnetic brush becomes coarse. As a result, an image having no graininess required in the photographic field or the like cannot be achieved.

  The particle size of the carrier can be within the above range by classification with an air classifier (Elbow Jet Lab EJ-L3, manufactured by Nippon Steel Mining Co., Ltd.) or the like.

  A method for measuring the 50% particle size (D50) based on the volume distribution will be described later.

The true specific gravity of the carrier is 2.5 to 4.2 g / cm ³ , preferably 2.7 to 4.1 g / cm ³ , and more preferably 3.0 to 4.0 g / cm ³ .

  Within this range, carrier adhesion on the photosensitive drum can be suppressed while maintaining high image quality. This is thought to be because the true specific gravity of the carriers is small, so that the impact when the carriers rub or collide with each other is reduced.

  Further, a two-component development method is used in which development is performed while supplying a replenishment developer containing at least toner and carrier to the developing device, and excess carrier inside the developing device is discharged from the developing device as needed. In this case, since the specific gravity difference between the carrier and the toner is small, the excess carrier is pumped up to the developer recovery port, and the excess carrier in the developing device can be effectively discharged. For this reason, high image quality can be maintained over a long period of time.

However, if the true specific gravity of the carrier exceeds 4.2 g / cm ³ , the impact when the carriers are rubbed or collided with each other in the developing machine is large, and as a result, the carrier is scraped, and toner and toner components are adhered, Carrier deterioration occurs. As a result, the chargeability of the carrier to the toner and the transfer efficiency are reduced. As a result, the amount of toner applied on the paper decreases, and the color development that can be achieved in the initial stage may not be maintained.

  Further, a two-component development method is used in which development is performed while supplying a replenishment developer containing at least toner and carrier to the developing device, and excess carrier inside the developing device is discharged from the developing device as needed. In this case, the specific gravity difference between the toner and the carrier becomes large. In particular, the coarse powder carrier is difficult to be pumped up to the developer collection port, and the carrier is hardly collected stably. As a result, the recovered carrier has a lot of fine carrier powder, and the carrier particle size becomes coarse. For this reason, when used for a long period of time, the graininess is lowered. In order to avoid this phenomenon, the apparatus tends to be complicated by strengthening the stirring mechanism.

On the other hand, when the true specific gravity of the carrier is less than 2.5 g / cm ³ , the toner is easily developed on the photosensitive drum at the time of development, and carrier adhesion may be caused to deteriorate the image quality.

  A method for measuring the true specific gravity will be described later.

In addition, the magnetization intensity of the carrier is 40 to 70 Am ² / kg under a magnetic field of 1000 / 4π (kA / m). When the carrier is within this range, an image with good dot reproducibility can be obtained over a long period of time. When the intensity of magnetization of the carrier is less than 40 kAm ² / kg, it is easy to be developed on the photosensitive drum at the time of development, and carrier adhesion may occur. When the magnetization intensity of the carrier exceeds 70 kAm ² / kg, the stress on the developer between the regulating blade 9 and the developing sleeve 8 increases, and the carrier may be deteriorated.

  A method for measuring the magnetization intensity will be described later.

  The carrier contained in the replenishment developer of the present invention preferably has an average circularity of 0.85 to 0.95 and contains 90% by number or more of particles having a circularity of 0.80 or more. The average circularity is preferably 0.87 to 0.93, more preferably 0.88 to 0.92. The average circularity is a coefficient representing the shape of the roundness of the particle, and is obtained from the maximum diameter of the particle and the measured particle projected area. An average circularity of 1.00 indicates a perfect sphere (perfect circle), and a smaller numerical value indicates an elongated or irregular shape.

  When the average circularity is 0.85 to 0.95, the carrier contained in the replenishment developer of the present invention has sufficient carrier strength, excellent chargeability to the toner, and toner or toner. Adhesion of components hardly occurs and has excellent durability. When the average circularity is less than 0.85, it means that the particles have an irregular shape. In this case, the charge imparting property to the toner may be deteriorated, which is not preferable. On the other hand, when the average circularity exceeds 0.95, the specific surface area of the carrier becomes small, and the chargeability to the toner may be lowered.

  A method for measuring the average circularity of the carrier will be described later.

  When the toner and the carrier are mixed and used as a two-component developer in the developing device, the mixing ratio of the toner and the carrier is 0.02 to 0.35 parts by mass with respect to 1 part by mass of the carrier. It is preferably 0.04 to 0.25 part by mass, more preferably 0.05 to 0.20 part by mass. If it is less than 0.02 parts by mass, the image density tends to be low, and if it exceeds 0.35 parts by mass, fog and in-machine scattering are likely to occur.

  The replenishment developer of the present invention can be used only with toner, but it is preferable to contain the toner in a blending ratio of 2 to 50 parts by mass with respect to 1 part by mass of the carrier. In this way, when a large amount of printing of about 10K (10,000 sheets) is performed, the carrier is rubbed or bumped in the developing machine, and toner and toner components adhere to the toner. Carriers with reduced efficiency can be discharged appropriately. As a result, high image density and high image quality can be maintained even when used for a long time.

  On the other hand, when the toner content is less than 2 parts by mass with respect to 1 part by mass of the carrier, it is necessary to replenish a large amount of replenishment developer particularly when an image having a high printing density is printed at a high speed. As a result, the developer for replenishment and the developer in the development period are used for development before being sufficiently mixed, and the toner charge becomes non-uniform, resulting in a decrease in image density.

  In addition, if the toner is contained in an amount of more than 50 parts by mass with respect to 1 part by mass of the magnetic carrier, even if the carrier cannot be discharged or can be discharged, only a very small amount can be discharged. Will be forced. As a result, the chargeability of the carrier to the toner and the transfer efficiency are lowered, and as a result, the amount of toner on the paper is lowered, and the color development that can be achieved in the initial stage may not be maintained.

  There are two types of electrophotographic process development systems that output full-color images: a rotary development system having at least one photosensitive drum and a plurality of developing units, and a tandem development system having a plurality of photosensitive drums and a plurality of developing units. In either case, the developer of the present invention and the developer for replenishment can be used.

  Examples of the developing device include the following.

  FIG. 2 shows the positional relationship between the image carrier (photosensitive drum) 10 and the developing device 1 in the full-color image forming apparatus.

  The developing device 100 regulates the developing sleeve (developer carrier) 8 and the layer thickness of the developer carried on the surface of the developing sleeve 8 in the developing container 2 in which a two-component developer containing toner and a magnetic carrier is accommodated. And a regulating blade 9 as a developer regulating member.

  Further, the developing container 2 has an opening at a position corresponding to the developing region facing the photosensitive drum 10, and the developing sleeve 8 is rotatably arranged so that the developing sleeve 8 is partially exposed to the photosensitive drum 10 side. It is installed. The developing sleeve 8 is made of a non-magnetic material, and a magnet roller 8 'as a first magnetic field generating means is installed in a non-rotating state inside the developing sleeve 8. The magnet roller 8 is connected to the developing pole S2 and the developing. It has magnetic poles S1, N1, N2, and N3 for conveying the agent.

  A substantially central portion in the developing container 2 is divided into a developing chamber 3 and an agitating chamber 4 by a partition wall 7 extending in a direction perpendicular to the paper surface, and the developer is accommodated in the developing chamber 3 and the agitating chamber 4. More desirable.

  This is because by dividing the developing chamber 3 and the stirring chamber 4 in this manner, the developer is sufficiently stirred and the mixed developer can be supplied to the developing sleeve 8 even during high-speed printing.

  In the developing chamber 3 and the agitating chamber 4, first and second conveying screws 5 and 6, which are circulation means for agitating and conveying the developer T and circulating in the developing container 2, are arranged, respectively. The first conveying screw 5 is disposed substantially parallel to the bottom of the developing chamber 3 along the axial direction of the developing sleeve 8, and rotates to allow the developer T in the developing chamber 3 to move in one direction along the axial direction. Transport. The second conveying screw 6 is disposed at the bottom of the stirring chamber 4 substantially in parallel with the first conveying screw 5 and conveys the developer T in the stirring chamber 4 in the opposite direction to the first conveying screw 5. . In this way, the developer T is transported between the developing chamber 3 and the agitating chamber 4 through the openings (communication portions) at both ends of the partition wall 7 by transport by the rotation of the first and second transport screws 5 and 6. Circulated.

  Further, the replenishment developer is replenished from a replenishment developer introduction port (not shown) installed in the stirring chamber 4, and the excess carrier in the developing unit is installed in the development chamber 3 as necessary. It is desirable to discharge from a certain waste outlet (not shown) because higher durability can be achieved.

  A suitable method for measuring physical properties related to the present invention will be described below.

<Measurement of toner particle size distribution and weight average particle size (D4)>
As a measuring device, Coulter Counter TA-II or Coulter Multisizer II (manufactured by Coulter Inc.) is used. As the electrolytic solution, an about 1% NaCl aqueous solution is used. As the electrolytic solution, an electrolytic solution prepared using primary sodium chloride or, for example, ISOTON (registered trademark) -II (manufactured by Coulter Scientific Japan) can be used.

  As a measurement method, 0.1 to 5 ml of a surfactant (preferably alkylbenzenesulfone hydrochloric acid) is added as a dispersant to 100 to 150 ml of the electrolytic aqueous solution, and 2 to 20 mg of a measurement sample is further added. The electrolytic solution in which the sample is suspended is dispersed for about 1 to 3 minutes with an ultrasonic disperser, and the volume and number of the sample are measured for each channel by the measuring apparatus using a 100 μm aperture as the aperture. Volume distribution and number distribution are calculated. From these obtained distributions, the weight average particle diameter (D4) of the sample is determined. As channels, 2.00 to 2.52 μm; 2.52 to 3.17 μm; 3.17 to 4.00 μm; 4.00 to 5.04 μm; 5.04 to 6.35 μm; 6.35 to 8. 00 μm; 8.00 to 10.08 μm; 10.08 to 12.70 μm; 12.70 to 16.00 μm; 16.00 to 20.20 μm; 20.20 to 25.40 μm; 25.40 to 32.00 μm; 13 channels of 32.00-40.30 μm are used.

<Measurement of average circularity of toner>
The equivalent circle diameter and circularity of the toner are used as a simple method for quantitatively expressing the shape of the toner particles. In the present invention, the flow type particle image measuring device “FPIA-2100 type” (manufactured by Sysmex Corporation) is used. ) Is used for calculation, and the following equations (1) to (2) are used for calculation.
(1): equivalent circle diameter = (particle projected area / π) ^1/2 × 2
(2): Circularity = (perimeter of a circle having the same area as the particle projection area) / (perimeter of the particle projection image)

  Here, the “particle projected area” is the area of the binarized toner particle image, and the “peripheral length of the particle projected image” is the length of the contour line obtained by connecting the edge points of the toner particle image. Define. The measurement uses the perimeter of the particle image when image processing is performed at an image processing resolution of 512 × 512 (pixels of 0.3 μm × 0.3 μm).

  In the present invention, the circularity is an index indicating the degree of unevenness of the toner particles, and is 1.000 when the toner particles are completely spherical. The more complicated the surface shape, the smaller the circularity.

  The average circularity C, which means the average value of the circularity frequency distribution, is calculated from the following equation, where ci is the circularity (center value) at the dividing point i of the particle size distribution and m is the number of measured particles.

  In addition, “FPIA-2100”, which is a measuring apparatus used in the present invention, calculates the circularity of each particle, and then calculates the average circularity. 1.0 is divided into classes equally divided every 0.01, and the average circularity is calculated using the center value of the division points and the number of measured particles.

  As a specific measuring method, 10 ml of ion-exchanged water from which impure solids have been removed in advance is prepared in a container, and a surfactant, preferably an alkylbenzene sulfonate, is added as a dispersant therein, followed by further measurement. Add 0.02 g of sample and disperse uniformly. As a means for dispersion, an ultrasonic disperser “Tetora 150 type” (manufactured by Nikka Ki Bios Co., Ltd.) is used, and dispersion treatment is performed for 2 minutes to obtain a dispersion for measurement. In that case, it cools suitably so that the temperature of this dispersion may not be 40 degreeC or more. In order to suppress variation in circularity, the installation environment of the apparatus is controlled at 23 ° C. ± 0.5 ° C. so that the temperature inside the flow type particle image analyzer FPIA-2100 is 26 to 27 ° C. Preferably, autofocus is performed using 2 μm latex particles every 2 hours.

  To measure the shape of the toner particles, the flow type particle image measuring device is used, and the concentration of the dispersion is readjusted so that the color toner particle concentration at the time of measurement is 3000 to 10,000 particles / μl. Measure more than one. After the measurement, this data is used to cut data less than 2 μm, and the average circularity of the toner particles is obtained.

  Furthermore, “FPIA-2100”, which is a measuring apparatus used in the present invention, improves the magnification of the processed particle image as compared with “FPIA-1000” conventionally used for calculating the shape of the toner. Furthermore, the accuracy of toner shape measurement is improved by improving the processing resolution of the captured image (256 × 256 → 512 × 512), thereby achieving more reliable capture of fine particles. Therefore, when it is necessary to measure the shape more accurately as in the present invention, the FPIA 2100 that can obtain information on the shape more accurately is more useful.

<Measurement of endothermic peak number of toner at 30 to 200 ° C. and maximum temperature of maximum endothermic peak>
Temperature curve: Temperature increase I (30 ° C. to 200 ° C., temperature increase rate 10 ° C./min)
Temperature drop I (200 ° C-30 ° C, temperature drop rate 10 ° C / min)
Temperature increase II (30 ° C. to 200 ° C., temperature increase rate 10 ° C./min)

  The maximum endothermic peak of the toner is measured according to ASTM D3418-82 using a differential scanning calorimeter (DSC measuring device) DSC2920 (manufactured by TA Instruments Japan).

  The measurement sample is precisely weighed in an amount of 3 to 7 mg, preferably 4 to 5 mg. The sample is put in an aluminum pan, and an empty aluminum pan is used as a reference, and measurement is performed at a temperature rise rate of 10 ° C./min at room temperature and humidity in a measurement range of 30 to 200 ° C.

  The number of endothermic peaks is the number of peak tops in the process of temperature increase II.

  For the maximum endothermic peak temperature, the temperature at the top of the peak with the highest endotherm among the peaks in the process of temperature increase II is measured.

<Carrier volume distribution standard 50% particle size (D50) and average circularity>
The 50% particle size (D50) and average circularity based on the volume distribution of the carrier are measured as follows using, for example, a multi-image analyzer (manufactured by Beckman Coulter).

  A solution obtained by mixing about 1% NaCl aqueous solution and glycerin at 50% by volume: 50% by volume is used as the electrolytic solution. Here, the NaCl aqueous solution may be prepared using primary sodium chloride, and may be, for example, ISOTON (registered trademark) -II (manufactured by Coulter Scientific Japan). Glycerin may be a special grade or first grade reagent.

  To the electrolytic solution (about 30 ml), 0.1 to 1.0 ml of a surfactant (preferably alkylbenzenesulfone hydrochloride) is added as a dispersant, and 2 to 20 mg of a measurement sample is further added. The electrolytic solution in which the sample is suspended is dispersed for about 1 minute with an ultrasonic disperser to obtain a dispersion.

  Using a 200 μm aperture and a 20 × lens as the aperture, the equivalent circle diameter and circularity are calculated under the following measurement conditions.

Average luminance within measurement frame: 220 to 230
Measurement frame setting: 300
SH (threshold): 50
Binarization level: 180

  The electrolytic solution and the dispersion liquid are put into a glass measuring container, and the concentration of carrier particles in the measuring container is set to 5 to 10% by volume. Stir the contents of the glass measuring container at the maximum stirring speed. The sample suction pressure is 10 kPa. When the carrier specific gravity is large and the sedimentation is likely to occur, the measurement time is 15 to 30 minutes. Further, the measurement is interrupted every 5 to 10 minutes to replenish the sample solution and the electrolytic solution-glycerin mixed solution.

  The number of measurements is 2000. After the measurement is finished, the main body software removes a defocused image, aggregated particles (multiple simultaneous measurements), etc. on the particle image screen.

The circularity and equivalent circle diameter of the carrier are calculated by the following formula.
Circularity = (4 × Area) / (MaxLength ² × π)
Circle equivalent diameter = √ (4 · Area / π)

  Here, “Area” is the projected area of the binarized carrier particle image, and “MaxLength” is defined as the maximum diameter of the carrier particle image. The equivalent circle diameter is represented by the diameter of a perfect circle when “Area” is the area of the perfect circle. The equivalent circle diameter is divided into 4 to 100 μm in 256, and is used by logarithmically displaying on a volume basis. Using this, the 50% particle size (D50) based on volume distribution is obtained. The average circularity is obtained by adding the circularity of each particle and dividing by the total number of particles. FIG. 4 shows an example of a graph of measurement results. The “arithmetic average value” in the “circularity arithmetic statistical value” section in the figure indicates the average circularity.

<Strength of magnetization of carrier>
The magnetization strength of the carrier contained in the replenishment developer of the present invention can be determined by a vibrating magnetic field type magnetic property device VSM (Vibrating sample magnetometer), a direct current magnetization property recording device (BH tracer), or the like. . Preferably, it can measure with an oscillating magnetic field type magnetic property apparatus. Examples of the oscillating magnetic field type magnetic property apparatus include an oscillating magnetic field type magnetic property automatic recording apparatus BHV-30 manufactured by Riken Denshi Co., Ltd. Using this, it can be measured by the following procedure. A cylindrical plastic container is packed sufficiently densely, while an external magnetic field of 1000 / 4π (kA / m) (1000 oersted) is created, and the magnetization moment of the carrier filled in the container is measured in this state. . Further, the actual mass of the carrier filled in the container is measured to determine the magnetization strength (Am ² / kg) of the carrier.

<Measurement of molecular weight by GPC>
The molecular weight of the chromatogram by gel permeation chromatograph (GPC) is measured under the following conditions.

Resin prepared by stabilizing the column in a heat chamber at 40 ° C., and flowing tetrahydrofuran (THF) as a solvent at a flow rate of 1 ml / min to the column at this temperature to adjust the sample concentration to 0.05 to 0.6% by mass. Measurement is performed by injecting 50 to 200 μl of a THF sample solution. An RI (refractive index) detector is used as the detector. As a column, in order to accurately measure a molecular weight region of 1 × 10 ³ to 2 × 10 ⁶ , it is preferable to combine a plurality of commercially available polystyrene gel columns. For example, μ-styragel 500, 103, 104 manufactured by Waters , 105, and combinations of shodex KA-801, 802, 803, 804, 805, 806, and 807 manufactured by Showa Denko KK are preferable.

In measuring the molecular weight of a sample, the molecular weight distribution of the sample is calculated from the relationship between the logarithmic value of a calibration curve prepared from several types of monodisperse polystyrene standard samples and the number of counts. As a standard polystyrene sample for preparing a calibration curve, for example, Pressure Chemical Co. Manufactured by Toyo Soda Kogyo Co., Ltd. and having molecular weights of 6 × 10 ² , 2.1 × 10 ³ , 4 × 10 ³ , 1.75 × 10 ⁴ , 5.1 × 10 ⁴ , 1.1 × 10 ⁵ , It is appropriate to use 3.9 × 10 ⁵ , 8.6 × 10 ⁵ , 2 × 10 ⁶ , 4.48 × 10 ⁶ , and use at least about 10 standard polystyrene samples.

  Specific examples of the present invention will be described below, but the present invention is not limited to these examples.

[Carrier Production Example 1]
4. A magnetite powder having a number average particle size of 0.30 μm and a magnetization strength of 72 Am ² / kg under a magnetic field of 1000 / 4π (kA / m) and a hematite powder having a number average particle size of 0.30 μm, respectively. 0% by mass of a silane coupling agent (3- (2-aminoethylaminopropyl) trimethoxysilane) was added, and the mixture was stirred and mixed at 110 ° C. or higher in a container to treat each fine particle.
・ Phenol 10 parts by mass ・ Formaldehyde solution 6 parts by mass (formaldehyde 40%, methanol 10%, water 50%)
-Treated magnetite 75 parts by mass-Treated hematite 9 parts by mass The above material, 5 parts by mass of 28% ammonia water, and 25 parts by mass of water are placed in a flask, and the temperature is raised and maintained up to 85 ° C over 40 minutes while stirring and mixing. The resulting phenol resin was cured by a polymerization reaction for 3 hours. Thereafter, the cured phenol resin was cooled to 30 ° C., water was further added, the supernatant was removed, the precipitate was washed with water, and then air-dried. Next, this is dried under reduced pressure (5 mmHg or less) at a temperature of 60 ° C., and a magnetic material-containing resin carrier core (hereinafter referred to as “magnetic material dispersion” in which spherical magnetic materials in which the magnetic materials are dispersed is dispersed. Also referred to as “resin core”.

  As a coating resin, a copolymer of methyl methacrylate and perfluorooctyl acrylate (copolymerization ratio (mass% ratio) 8: 2, weight average molecular weight 40,000) is used, and this is 100 mass of the magnetic material dispersed resin core at the time of coating. A carrier coat solution containing 10% by mass of a copolymer of methyl methacrylate and perfluorooctyl acrylate was prepared using a mixed solvent of methyl ethyl ketone and toluene as a solvent so as to be 1 part by mass with respect to parts. In addition, 1.0 part by mass of melamine resin (number average particle diameter 0.2 μm) and 1.0 part by mass of carbon black (number average particle diameter 30 nm, DBP oil absorption 50 ml / 100 g) may be added to the carrier coat solution using a homogenizer. Mix. Next, the magnetic material-dispersed resin core is added to the mixed solution, and the solvent is volatilized at 70 ° C. while continuously applying shear stress to the mixed solution, and the methyl methacrylate and perfluorooctyl acrylate are applied to the surface of the magnetic material-dispersed resin core. And a copolymer.

  The resin-coated magnetic material-dispersed resin core coated with a copolymer of methyl methacrylate and perfluorooctyl acrylate is heat-treated by stirring at 100 ° C. for 2 hours, cooled, crushed, and classified with a 200 mesh sieve. Carrier 1 was obtained. The physical properties of Carrier 1 are shown in Table 1.

[Carrier Production Example 2]
In Carrier Production Example 1, 0.45 [mu] m and the number average particle diameter of the magnetite powder from 0.30 .mu.m, the magnetization intensity 80 Am ² / kg from 72Am ² / kg, and 25 parts by mass from 10 parts by weight of phenol, formaldehyde solution Carrier 2 was obtained in the same manner as Carrier Production Example 1 except that the amount was changed from 6 parts by mass to 15 parts by mass. Table 1 shows the physical properties of Carrier 2.

[Carrier Production Example 3]
Ferrite component Fe ₂ O ₃ : 56.3 mol%
MgO: 23.0 mol%
SrO: 20.7 mol%
The ferrite raw material oxide blended in the above composition was wet-mixed with a ball mill, dried and ground, then fired at 750 ° C. for 2 hours, and ground with a crusher to about 0.1 to 1.0 mm. Furthermore, it was wet pulverized by a ball mill to form a slurry, added with 1.0% polyvinyl alcohol as a binder and 3% CaCO ₃ as a pore adjuster, granulated into spherical particles by a spray dryer method, and an oxygen gas concentration of 0.5 The mixture was calcined at 950 ° C. in a nitrogen gas atmosphere of% and sieved with a sieve having an opening of 250 μm to remove coarse particles. Subsequently, classification was performed with an air classifier (Elbow Jet Lab EJ-L3, manufactured by Nippon Steel Mining Co., Ltd.) to obtain a carrier core which is a porous magnetic material.

Next, toluene and methyl ethyl ketone (4: 1) mixed solvent 1000 parts by mass Styrene / methyl methacrylate copolymer (4: 6, M _w = 50,000) 70 parts by mass Methyl methacrylate / perfluoropropyl ethyl methacrylate copolymer
(80:20, M _w = 18,000) 30 parts by mass The above components were mixed to prepare a coating liquid. Next, the composition of the solution is adjusted so that the solid content of the coating resin is 5.0% by mass with respect to the carrier core which is the porous magnetic material, and the solvent is removed by drying under reduced pressure while stirring and mixing with a vacuum kneader. The carrier 5 was obtained by baking at 140 ° C. for 2 hours and sieving with a sieve having an opening of 74 μm. Table 1 shows the physical properties of Carrier 3.

[Carrier Production Example 4]
In the carrier 3 production example, the carrier 4 is changed in the same manner as the carrier production example 3 except that the CaCO ₃ is changed from 3% to 15% and the classification condition, specifically, the set value of the suction air volume is changed. Obtained. The physical properties of the carrier 4 are shown in Table 1.

[Carrier Production Example 5]
These metal oxide particles were weighed so that the molar ratio was Fe ₂ O ₃ = 89.8 mol% and MgO = 10.2 mol%, and mixed using a ball mill. After calcining the obtained mixed powder, it is pulverized by a ball mill, further granulated by a spray dryer, sintered, and further classified to form a carrier core (hereinafter referred to as “magnetic particles”) that is a porous magnetic material. Also referred to as).

  Furthermore, the surface of the magnetic particles obtained above was coated with a thermosetting silicone resin by the following method. Carrier coat containing 10% by mass of silicone resin using toluene as a solvent so that the coating amount of the silicone resin on the surface of the magnetic particles becomes 2.0 parts by mass with respect to 100 parts by mass of the resin-coated magnetic particles after coating. A solution was made.

  The magnetic particles were added to the carrier coating solution, and the silicone resin was coated on the surface of the magnetic particles by volatilizing the solvent at 70 ° C. while continuously applying shear stress thereto.

  The resin-coated magnetic particles coated with the silicone resin are heat-treated by stirring at 200 ° C. for 3 hours, then cooled and crushed, and screened with a 200-mesh sieve to remove coarse particles, and then an air classifier ( Classification was carried out with Elbow Jet Lab EJ-L3 (manufactured by Nippon Steel Mining Co., Ltd.), and the particle size was adjusted to obtain Carrier 5. Table 1 shows the physical properties of the carrier 5.

[Binder resin production example]
As the material of the vinyl polymer unit, 2.0 mol of styrene, 0.21 mol of 2-ethylhexyl acrylate, 0.14 mol of fumaric acid, 0.03 mol of α-methylstyrene dimer, dicumylpar as a crosslinking agent and a polymerization initiator 0.05 mol of oxide was put into the dropping funnel. As a material of the polyester unit, 7.0 mol of polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, polyoxyethylene (2.2) -2,2-bis (4-hydroxyphenyl) ) 3.0 mol of propane, 3.0 mol of terephthalic acid, 1.9 mol of trimellitic anhydride, 5.0 mol of fumaric acid and 0.2 g of dibutyltin oxide were put into a 4-liter four-necked flask made of glass. A thermometer, a stirring rod, a condenser, and a nitrogen introducing tube were attached to the four-necked flask, and the four-necked flask was placed in a mantle heater. Next, after the inside of the four-necked flask was replaced with nitrogen gas, the temperature was gradually increased while stirring, and the monomer and polymerization of the vinyl polymer unit were performed from the previous dropping funnel while stirring at a temperature of 145 ° C. The initiator was added dropwise over 4 hours. Next, the obtained product was heated to 200 ° C. and reacted for 4 hours to obtain a hybrid resin. As for the molecular weight of this hybrid resin by GPC, the weight average molecular weight (M _w ) was 81500, the number average molecular weight (Mn) was 3100, and the peak molecular weight was 15500.

[Toner Production Example 1]
Binder resin 100 parts by mass Paraffin wax (melting point 78 ° C., number average molecular weight 592) 5 parts by mass 3,5-di-t-butylsalicylic acid aluminum compound 1 part by mass I. Pigment Red 177 4 parts by mass, C.I. I. Pigment Red 168 4 mass The above materials a Henschel mixer (FM-75 type, Mitsui Miike Machinery Co., Ltd.) was well mixed with a twin-screw kneader was set to a temperature 130 ° C. (PCM-30 type, manufactured by Ikegai Kneading was carried out by an ironworker. The obtained kneaded material was cooled and coarsely pulverized to 1 mm or less with a hammer mill to obtain a coarsely pulverized material. The obtained coarsely crushed material was finely pulverized using a collision type airflow pulverizer using a high-pressure gas (IDS-5 manufactured by Nippon Pneumatic Industry Co., Ltd.). The obtained finely pulverized product had a weight average particle diameter (D4) of 5.9 μm and an average circularity of 0.922.

  Next, the obtained finely pulverized product is put into the surface reforming apparatus at a rate of 1.3 kg per time using the surface reforming apparatus shown in FIG. 3, and the rotation speed of the classification rotor 35 is set to 7300 rpm to remove the fine particles. However, the surface treatment was performed for 70 seconds at a rotation speed of the dispersion rotor 32 of 5800 rpm (rotational peripheral speed 130 m / sec). The valve 41 was opened and taken out as a processed product).

At this time, in this embodiment, ten square disks 33 are installed on the upper part of the dispersion rotor 32, the distance between the guide ring 36 and the square disk 33 on the dispersion rotor 32 is 30 mm, and the dispersion rotor 32 and the liner 34 are arranged. Was set at 5 mm. The blower air volume was 14 m ³ / min, the temperature of the refrigerant passed through the jacket and the cold air temperature T1 were −20 ° C.

  As a result of repeated operation for 20 minutes in this state, the temperature T2 behind the classification rotor 35 was stabilized at 27 ° C. The toner particles obtained after the surface treatment had a weight average particle diameter (D4) of 6.5 μm, an average circularity of 0.940, and a classification yield of 82%.

Furthermore, using a mesh surface fixed wind sieve high voltor (NR-300 type, manufactured by Shin Tokyo Machine Co., Ltd .: air brush attached to the back of the wire mesh), this has a diameter of 30 cm, an opening of 29 μm, and an average diameter of the wire Was provided with a 30 μm metal mesh, and the toner powder was supplied to the metal mesh in an air stream having an air volume of 5 Nm ³ / min to obtain toner particles from which coarse particles were separated. The obtained toner particles had a particle diameter of 12.7 μm or more and less than 0.1% by volume. Further, the separated coarse particles were about 0.2% by mass of the toner particles that passed through the sieve.

  To 100 parts by mass of the obtained toner particles, 1.0 part by mass of titanium oxide having an average particle diameter of 40 nm and hydrophobized and 0.5 part by mass of amorphous silica having an average particle diameter of 110 nm were added as inorganic fine particles. Addition and mixing were performed to obtain toner 1. Table 2 shows the physical properties of Toner 1 thus obtained.

[Toner Production Example 2]
In Toner Production Example 1, C.I. I. Pigment Red 177 4 parts by mass and C.I. I. Pigment Red 168 Instead of 4 parts by mass, C.I. I. Toner 2 in the same manner as in Toner Production Example 1, except that 8 parts by weight of Pigment Red 177 and 5 parts by weight of Fischer-Tropsch wax (105 ° C.) were used instead of 5 parts by weight of paraffin wax (melting point 78 ° C., number average molecular weight 592). Got. Table 2 shows the physical properties of Toner 2 thus obtained.

[Toner Production Example 3]
In Toner Production Example 1, C.I. I. Pigment Red 177 4 parts by mass and C.I. I. Pigment Red 168 instead of 4 parts by mass C.I. I. Pigment Red 57: 1 4 parts by mass and C.I. I. Toner 3 was obtained in the same manner as in Toner Production Example 1 except that 4 parts of Pigment Yellow 180 were used. Table 2 shows the physical properties of Toner 3 thus obtained.

[Toner Production Example 4]
In Toner Production Example 1, C.I. I. Pigment Red 177 4 parts by mass and C.I. I. Pigment Red 168 Instead of 4 parts by mass, C.I. I. Toner 4 was obtained in the same manner as in Toner Production Example 1 except that 8 parts by mass of Pigment Red 177 was used and the treatment by the surface modifying apparatus shown in FIG. Table 2 shows the physical properties of Toner 4.

[Toner Production Example 5]
In Toner Production Example 1, C.I. I. Pigment Red 177 4 parts by mass and C.I. I. Pigment Red 168 instead of 4 parts by mass C.I. I. Toner 5a was obtained in the same manner as in Toner Production Example 1 except that 4 parts by mass of Pigment Red 122 was used.

  In Toner Production Example 1, C.I. I. Pigment Red 177 4 parts by mass and C.I. I. Pigment Red 168 instead of 4 parts by mass C.I. I. Toner 5b was obtained in the same manner as in Toner Production Example 1 except that 4 parts by mass of Pigment Yellow 180 was used.

  The toners 5a and 5b were mixed at a ratio of 1: 1 to obtain a toner 3. Table 2 shows the physical properties of Toner 3.

[Toner Production Example 6]
In Toner Production Example 1, C.I. I. Pigment Red 177 4 parts by mass and C.I. I. Pigment Red 168 Instead of 4 parts by mass, C.I. I. Toner 6 was obtained in the same manner as in Toner Production Example 1 except that 8 parts by weight of Pigment Red 177 was used and 5 parts by weight of paraffin wax (melting point 78 ° C., number average molecular weight 592) was not used. Table 2 shows the physical properties of Toner 6.

[Toner Production Example 7]
To 710 parts by mass of ion-exchanged water, 450 parts by mass of 0.1 M Na ₃ PO ₄ aqueous solution was added and heated to 60 ° C., and then at 12000 rpm using a TK homomixer (made by Tokushu Kika Kogyo). Stir. To this, 68 parts by mass of 1.0 M CaCl ₂ aqueous solution was gradually added to obtain an aqueous medium containing Ca ₃ (PO ₄ ) ₂ .

on the other hand,
-Styrene 100 mass parts-N-butyl acrylate 20 mass parts-C.I. I. Pigment Red 168 8 parts by mass, 3,5-di-t-butylsalicylic acid aluminum compound 1 part by mass, saturated polyester (polar resin, Mp = 8000) 7 parts by mass, ester wax (melting point 67 ° C., number average molecular weight 590) 14 Part by mass The above material was heated to 60 ° C., and uniformly dissolved and dispersed at 10,000 rpm using a TK homomixer (manufactured by Tokushu Kika Kogyo). In this, 7 parts by mass of a polymerization initiator 2,2′-azobis (2,4-dimethylvaleronitrile) was dissolved to prepare a polymerizable monomer composition.

The polymerizable monomer composition was charged into an aqueous medium, and stirred at 10,000 rpm for 10 minutes with a TK homomixer in an N ₂ atmosphere at 60 ° C. to granulate the polymerizable monomer composition. Then, while stirring with a paddle stirring blade, the temperature was raised to 80 ° C. and reacted for 10 hours. After completion of the polymerization reaction, the residual monomer was distilled off under reduced pressure. After cooling, hydrochloric acid was added to dissolve Ca ₃ (PO ₄ ) _{2 and the} like, followed by filtration, washing with water and drying to obtain toner particles.

  Hydrophobicized silica fine powder (hexamethyldisilazane 10% treated) (number average particle size of primary particles: 0.03 μm) 0.5 parts by mass with respect to 100 parts by mass of the obtained toner particles Toner 7 was obtained by externally adding 0.5 parts by mass of titania powder (treated with 5% hexamethyldisilazane) (number average particle diameter of primary particles: 0.03 μm). Table 2 shows the physical properties of Toner 7 thus obtained.

[Toner Production Example 8]
Dispersion A
Styrene 350 parts by mass n-butyl acrylate 100 parts by mass Acrylic acid 25 parts by mass t-dodecyl mercaptan 10 parts by mass The above composition was mixed and dissolved to prepare monomer mixture A.
Paraffin wax (melting point 75 ° C., number average molecular weight 518) dispersion 200 parts by mass (solid content concentration 30%, dispersion particle size 0.14 μm)
1.2 parts by weight of anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen SC)
0.5 parts by weight of nonionic surfactant (manufactured by Sanyo Chemical Co., Ltd .: Nonipol 400)
Ion-exchanged water 1530 parts by mass The above composition is dispersed in a flask, and heating is started while performing nitrogen substitution. When the liquid temperature reached 70 ° C., a solution prepared by dissolving 6.56 parts by mass of potassium persulfate with 350 parts by mass of ion-exchanged water was added thereto. While maintaining the liquid temperature at 70 ° C., the monomer mixture A was charged and stirred, and the liquid temperature was raised to 80 ° C. and emulsion polymerization was continued for 5 hours. After that, the liquid temperature was adjusted to 40 ° C. and filtered through a filter. A was obtained. Thus, the particle diameter in the obtained dispersion is 0.17 μm in average particle diameter, the glass transition point of solid content is 60 ° C., the weight average molecular weight (M _w ) is 14,000, and the peak molecular weight is 11 000. Paraffin wax was contained in the polymer in an amount of 6% by mass. As a result of observing a thin piece of this solid content with a transmission electron microscope, it was confirmed that the polymer particles encapsulated the wax particles.

Dispersion B
Styrene 350 parts by mass n-butyl acrylate 100 parts by mass Acrylic acid 30 parts by mass The above ratios were mixed and dissolved to prepare monomer mixture B.

Fischer-Tropsch wax (melting point 105 ° C.) 50 parts by mass (solid content concentration 30%, dispersion particle size 0.15 μm)
1.5 parts by weight of anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen SC)
0.5 parts by weight of nonionic surfactant (manufactured by Sanyo Chemical Co., Ltd .: Nonipol 400)
Ion-exchanged water 1530 parts by mass The above composition is dispersed in a flask, and heating is started while performing nitrogen substitution. When the liquid temperature reached 65 ° C., a solution prepared by dissolving 5.85 parts by mass of potassium persulfate with 300 parts by mass of ion-exchanged water was added thereto. While maintaining the liquid temperature at 65 ° C., the monomer mixture B was charged and stirred, and the liquid temperature was raised to 75 ° C. and emulsion polymerization was continued for 8 hours. The liquid temperature was adjusted to 40 ° C. and filtered through a filter. B was obtained. Thus, the particle size in the obtained dispersion was 0.16 μm in average particle size, 63 ° C. in glass transition point of solid content, and 650,000 in weight average molecular weight (M _w ). The hydrocarbon wax was contained in the polymer in an amount of 6% by mass, and as a result of observing a thin piece of the solid content with a transmission electron microscope, it was confirmed that the wax particles were encapsulated.

Dispersion C
C. I. Pigment Red 177 12 parts by mass Anionic surfactant 2 parts by mass (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen SC)
78 parts by mass of ion-exchanged water were mixed and dispersed using a sand grinder mill to obtain a colorant dispersion C.

  300 parts by mass of the dispersion A, 150 parts by mass of the dispersion B, and 25 parts by mass of the dispersion C were put into a 1-liter separable flask equipped with a stirrer, a cooling tube, and a thermometer and stirred. As a flocculant, 180 parts by mass of a 10% sodium chloride aqueous solution was dropped into this mixed solution, and the flask was heated to 54 ° C. while stirring the inside of the flask. After maintaining at 48 ° C. for 1 hour, it was confirmed by observation with an optical microscope that associated particles having a diameter of about 5 μm were formed.

  In the subsequent fusion process, after adding 3 parts by mass of an anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen SC), the stainless steel flask was sealed and stirring was continued using a magnetic seal. While heating to 100 ° C., it was held for 3 hours. Then, after cooling, the reaction product was filtered, sufficiently washed with ion exchange water, and then dried to obtain toner particles 7.

With respect to 100 parts by mass of the toner particles, 0.7 parts by mass of hydrophobic silica having a BET specific surface area of 200 m ² / g (hexamethyldisilazane 10% treatment) and hydrophobic titanium oxide having a primary particle diameter of 80 nm (hexa (Methyldisilazane 5% treatment) 0.7 parts by mass was added and dry-mixed to obtain toner 8. Table 2 shows the physical properties of Toner 8 thus obtained.

[Toner Production Example 9]
10.0 mol of ethylene glycol, 3.5 mol of terephthalic acid, 6.5 mol of 1,10-decanedicarboxylic acid and 0.2 g of dibutyltin oxide were put in a 4-liter four-necked flask made of glass. A thermometer, a stirring rod, a condenser, and a nitrogen introducing tube were attached to the four-necked flask, and the four-necked flask was placed in a mantle heater. Next, after the inside of the four-necked flask was replaced with nitrogen gas, the temperature was gradually raised to 200 ° C. while stirring and reacted for 4 hours to obtain a polyester resin. As for the molecular weight of this polyester resin by GPC, the peak molecular weight was 15500, and the weight average molecular weight (M _w ) was 81500.

  100 parts by weight of the obtained polyester resin and 20 parts by weight of a paraffin wax dispersion having a melting point of 75 ° C. used in Toner Production Example 8 were placed in 860 parts by weight of ion-exchanged water and stirred at 90 ° C. with a sand grinder mill. A polyester resin dispersion A was prepared.

  450 parts by weight of this polyester resin dispersion A and 25 parts by weight of dispersion C used in Toner Production Example 8 were put into a 1 liter separable flask equipped with a stirrer, a cooling tube and a thermometer and stirred. As a flocculant, 180 parts by mass of a 10% sodium chloride aqueous solution was dropped into this mixed solution, and the flask was heated to 54 ° C. while stirring the inside of the flask. After maintaining at 48 ° C. for 1 hour, it was confirmed by observation with an optical microscope that associated particles having a diameter of about 5 μm were formed.

  In the subsequent fusion process, after adding 3 parts by mass of an anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen SC), the stainless steel flask was sealed and stirring was continued using a magnetic seal. While heating to 100 ° C., it was held for 3 hours. Then, after cooling, the reaction product was filtered, thoroughly washed with ion exchange water, and then dried to obtain toner particles 8.

With respect to 100 parts by mass of the toner particles, 0.7 parts by mass of hydrophobic silica having a BET specific surface area of 200 m ² / g (hexamethyldisilazane 10% treatment) and hydrophobic titanium oxide having a primary particle diameter of 70 nm (hexa Methyldisilazane 5% treatment) 0.7 part by mass was added and dry-mixed to obtain toner 9. Table 2 shows the physical properties of Toner 9 thus obtained.

[Toner Production Example 10]
(Synthesis of organic fine particle emulsion)
In a reaction vessel equipped with a stirrer and a thermometer, 700 parts by weight of water, 10 parts by weight of sodium salt of ethylene oxide methacrylate adduct sulfate (Eleminol RS-30, manufactured by Sanyo Chemical Industries), 170 parts by weight of methacrylic acid, acrylic When 110 parts by mass of butyl acid and 1 part by mass of ammonium persulfate were charged and stirred at 3800 rpm for 30 minutes, a white emulsion was obtained. The system was heated to raise the system temperature to 75 ° C. and reacted for 4 hours. Further, 30 parts by mass of a 1% ammonium persulfate aqueous solution was added, and the mixture was aged at 75 ° C. for 6 hours to obtain an aqueous vinyl resin (methacrylic acid-butyl acrylate-methacrylic acid ethylene oxide adduct sulfate sodium salt copolymer). A dispersion was obtained.

(Preparation of aqueous phase)
990 parts by mass of water, 80 parts by mass of the above-mentioned aquatic dispersion, 40 parts by mass of a 48.3% aqueous solution of sodium dodecyl diphenyl ether disulfonate (Eleminol MON-7, manufactured by Sanyo Chemical Industries), and 90 parts by mass of ethyl acetate were mixed and stirred to give a milky white color Obtained liquid. This is referred to as [aqueous phase].

(Synthesis of low molecular weight polyester)
In a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen introduction tube, 750 parts by mass of bisphenol A propylene oxide 2 mol adduct, 200 parts by mass of terephthalic acid, 50 parts by mass of adipic acid and 2 parts by mass of dibutyltin oxide were added. After reacting at 230 ° C. for 7 hours at normal pressure and further 5 hours at a reduced pressure of 10 to 15 mmHg, 44 parts by weight of trimellitic anhydride was placed in the reaction vessel, and reacted for 3 hours at 180 ° C. and normal pressure. Low molecular weight polyester] was obtained.

(Synthesis of intermediate polyester)
In a reaction vessel equipped with a cooling pipe, a stirrer and a nitrogen introduction pipe, 680 parts by mass of bisphenol A ethylene oxide 2 mol adduct, 80 parts by mass of bisphenol A propylene oxide 2 mol adduct, 280 parts by mass of terephthalic acid, 20 parts by mass of merit acid and 2 parts by mass of dibutyltin oxide were added, reacted at 230 ° C. under normal pressure for 7 hours, and further reacted for 5 hours at a reduced pressure of 10 to 15 mmHg to obtain an [intermediate polyester].

  Next, 410 parts by mass of [intermediate polyester], 90 parts by mass of isophorone diisocyanate, and 500 parts by mass of ethyl acetate were 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. [Prepolymer] was obtained.

(Synthesis of ketimine)
In a reaction vessel equipped with a stirrer and a thermometer, 170 parts by mass of isophoronediamine and 75 parts by mass of methyl ethyl ketone were charged and reacted at 50 ° C. for 4 hours and half to obtain a [ketimine compound].

(Synthesis of master batch (MB))
1200 parts by weight of water, C.I. I. Pigment Red 177 600 parts by mass, polyester resin 1200 parts by mass, mixed with a Henschel mixer (Mitsui Mining Co., Ltd.), kneaded at 130 ° C. for 1 hour using two rolls, cooled with rolling and pulverized with a pulverizer. [Masterbatch] was obtained.

(Production of oil phase)
A container equipped with a stir bar and a thermometer was charged with 380 parts by mass of [low molecular polyester], 100 parts by mass of paraffin wax (melting point 69 ° C., number average molecular weight 468), and 950 parts of ethyl acetate, and the temperature was raised to 80 ° C. with stirring. And kept at 80 ° C. for 5 hours, and then cooled to 30 ° C. over 1 hour. Next, 500 parts by mass of [Masterbatch] and 500 parts by mass of ethyl acetate were charged in a container and mixed for 1 hour to obtain [Raw material solution].

  [Raw material solution] Transfer 1320 parts by mass to a container and use a bead mill (Ultra Visco Mill, manufactured by Imex Co., Ltd.) to feed liquid at a rate of 1 kg / hr, a disk peripheral speed of 6 m / sec, and 0.5% zirconia beads at 80% by volume. Carbon black and wax were dispersed under conditions of filling and 3 passes. Next, 1320 parts by mass of a 65% ethyl acetate solution of [low molecular weight polyester] was added, and two passes were performed with a bead mill under the above conditions to obtain [Pigment / Wax Dispersion].

(Emulsification / desolvation)
[Pigment / Wax Dispersion] 750 parts by mass, [Prepolymer] 110 parts by mass, and [Ketimine Compound] 3 parts by mass were placed in a container and mixed for 2 minutes at 5,000 rpm with a TK homomixer (made by Tokushu Kika). Thereafter, 1200 parts by mass of [aqueous phase] was added to the container, and the mixture was mixed with a TK homomixer at a rotation speed of 13,000 rpm for 25 minutes to obtain a slurry.

  The slurry was put into a container equipped with a stirrer and a thermometer, and after removing the solvent at 30 ° C. for 8 hours, aging was carried out at 45 ° C. for 8 hours to obtain [Dispersed slurry].

(Washing and drying)
[Dispersion slurry] After filtering 100 parts by mass under reduced pressure,
1. 100 parts by mass of ion-exchanged water was added to the filter cake, mixed with a TK homomixer (rotation speed: 12,000 rpm for 10 minutes), and then filtered.
2. 100 parts by mass of a 10% aqueous sodium hydroxide solution was added to the filter cake and mixed with a TK homomixer.
3. (30 minutes at 12,000 rpm), and then filtered under reduced pressure.
4). 100 parts by mass of 10% hydrochloric acid was added to the filter cake, mixed with a TK homomixer (rotation speed: 12,000 rpm for 10 minutes), and then filtered.
5. To the filter cake, 300 parts by mass of ion-exchanged water was added, mixed with a TK homomixer (rotation speed: 12,000 rpm for 10 minutes), and then filtered twice to obtain [filter cake].

  The [filter cake] was dried at 45 ° C. for 48 hours in a circulating dryer. Thereafter, sieved toner particles were obtained with a mesh opening of 75 μm. To 100 parts by mass of the obtained toner particles, 1.0 part by mass of titanium oxide having an average particle diameter of 40 nm and hydrophobized and 0.5 part by mass of amorphous silica having an average particle diameter of 110 nm were added as inorganic fine particles. Addition and mixing were performed to obtain toner 10. Table 2 shows the physical properties of Toner 10 thus obtained.

  The magnetic carrier and toner produced as described above were mixed in a combination and ratio as shown in Table 3 using a tumbler mixer to produce a developer / replenishment developer.

  Next, the developing device of a commercially available color copier CLC-5100 (Canon Inc.) was modified as shown in FIG.

  Further, when a replenishment developer (Examples 1 to 6) containing at least a toner and a carrier is used, a replenishment developer is supplied from a replenishment developer introduction port (not shown) installed in the stirring chamber 4. The excess carrier was modified so that it could be discarded from a disposal port (not shown) installed in the developing chamber 3.

When a developer for replenishment that does not contain a carrier ( Reference Example 1, Example 7, Reference Example 2 , Comparative Example 1 or 2 ) is used, a replenishment developer inlet (not shown) installed in the stirring chamber 4 is used. ) Modified to introduce replenishment developer.

In Examples 1 to 6, Reference Example 1 and Example 7 , and Comparative Examples 1 and 2, the oil application mechanism was removed. The developer was charged with 500 g of developer, and replenished developer was replenished as needed during printing.

Various evaluations were made after 100,000 sheets were printed under the following conditions using this modified machine.
Printing environment: 35 ° C / 90%
Paper: Color laser copier paper (81.4 g / m ² ) (Canon Sales Co., Ltd.)
Image forming speed: 400mm / sec
Development sleeve rotation speed: 500 mm / sec

  The evaluation methods and standards are shown below.

(1) a ^* b ^{* of the} image
A solid image with an image area of 100% (initial toner loading 0.70 mg / cm ² ) was printed and measured.

  For colorimetry. For measurement, Spectrolino (measuring condition: D50 viewing angle 2 °) manufactured by GretagMacbeth was used.

The color reproduction range (a * b * plane) obtained from JAPAN COLOR SOLID VALUE (CIELAB value) was compared with the color tone of a solid image with 100% image area of the red toner of the present invention.
A: The saturation is higher by Δ4 or more than Japan Color.
B: Δ2 or more and less than 4, and saturation is higher than Japan Color.
C: The difference from Japan Color is less than Δ2.
D: The saturation is lower than that of Japan Color by Δ2 or more.

(2) Spectral reflectance in the powder state The reflectance of the toner in the powder state is determined by using a spectroscopic color difference meter “SE-2000” (manufactured by Nippon Denshoku Industries Co., Ltd.) in accordance with JIS Z-8722. These conditions were measured using a C light source twice as a visual field. The measurement was performed according to the attached instruction manual. Standard alignment of the standard plate was performed in a state where a glass having a thickness of 2 mm and a diameter of 30 mm was interposed in an optional powder measurement cell. Before installing the cell on the sample table for the powder sample, 80% or more of the powder sample is filled with respect to the internal volume of the cell, and vibration with a swing width of 1 cm is performed once per second on the vibration table. Measured after adding for 2 seconds.
An example of the measurement result is shown in FIG.
A: Spectral reflectance of the toner in the powder state is 20% or less in the range of 380 to 520 nm, 10% or less in the range of 520 nm, and 60% or more in the range of 600 to 780 nm B: The toner in the powder state Spectral reflectance is 20% or less in the range of 380 to 500 nm, 10% or less at 500 nm, and 60% or more in the range of 600 to 780 nm C: Spectral reflectance of toner in powder state is 380 to 500 nm 20% or less in the range of, and 15% or less at 500 nm, 60% or more in the range of 620 to 780 nm D: outside the above range

(3) Graininess of image A solid image having an image area of 20% (initial toner loading 0.14 mg / cm ² ) was printed, and the graininess was visually determined from 10 cm from the paper.
A: No graininess.
B: There is some graininess.
C: Although there is a granular feeling, there is no problem level.
D: There is a granular feeling.

(4) Solid image uniformity A solid image having an image area of 50% (initial toner loading amount of 0.35 mg / cm ² ) was printed.

Using a Macbeth Densitometer RD918 type (Macbeth Densitometer RD918manufactured by Mcbeth Co.) equipped with an SPI filter, the maximum density difference was determined by measuring the four corners and the center of the image.
A: 0.00 or more and less than 0.05 B: 0.05 or more and less than 0.10 C: 0.10 or more and less than 0.20 D: 0.20 or more

(5) Glossiness of image A solid image having an image area of 100% (initial toner load 0.70 mg / cm ² ) was printed.

  The difference in gloss between the media before printing and the non-image area after printing was obtained.

Glossiness measured 60 degree glossiness using Nippon Denshoku Industries Co., Ltd. HANDY GLOSSMETER PG-1M.
A: Less than Δ20 B: Δ20 or more and less than 25 C: Δ25 or more and less than 30 D: Δ30 or more The results of these evaluations are shown in Table 4.

  In Examples 1 to 5, a * b * of the image after printing 100,000 sheets, spectral reflectance in the powder state, image granularity, solid image uniformity, gloss difference before and after printing of the media, all good Met. In particular, the a * b * of the image greatly exceeded the color reproduction range of Japan Color.

  In Example 6, the a * and b * of the image were slightly higher than Japan Color. This seems to be because the melting point of the wax used is slightly high at 105 ° C., and the pigment dispersion effect was not sufficient.

In Reference Example 1 , the uniformity of the image was slightly deteriorated. This is because the replenishment developer does not contain a carrier, and therefore, after printing 100,000 sheets, the external additive in the toner adheres to the carrier, and as a result, the toner cannot be uniformly charged. I think that the.

  Moreover, the graininess of the image is also deteriorated although it is at a satisfactory level. This is presumably because the carrier particle size was slightly large at 70 μm and the specific gravity of the carrier was slightly small at 2.5, so that the carrier partially adhered to the drum and disturbed the image.

  The spectral reflectance in the powder state was slightly poor, and the a * b * of the image was only equivalent to that of Japan Color. This is probably because Pigment Red 57: 1 and Pigment Yellow 180, which are two types of pigments, Magenta and Yellow, are used in combination, and Red toner is not used.

In Example 7 , although the level was not a problem, the uniformity of the image was slightly deteriorated. This seems to be because, since no carrier is used for the replenishment developer, the external additive in the toner adheres to the carrier after printing 100,000 sheets and the toner cannot be uniformly charged. .

  Further, the spectral reflectance in the powder state was slightly poor, and the a * b * of the image was equivalent to that of Japan Color. This seems to be because the circularity of the toner was less than 0.930, so that the transfer efficiency was lowered after printing 100,000 sheets, and as a result, the amount of toner was reduced.

In Reference Example 2 , the spectral reflectance in the powder state was slightly poor, and the a * b * of the image was equivalent to that of Japan Color. This seems to be because the dispersion of the pigment was somewhat worse because no wax was used. Further, since silicone oil is used without using wax, the media after printing is too glossy compared to the media before printing.

  In Comparative Example 1, the spectral reflectance in the powder state was poor, and the a * b * of the image was also worse than Japan Color. This is probably because magenta and yellow toner were mixed in powder form.

In Comparative Example 2, the uniformity of the image was poor. This is because the specific gravity of the carrier is larger than 4.2 g / cm ² , and the impact when the carriers are rubbed or collided when printing 100,000 sheets is strong, the carrier coating agent is peeled off, and the toner adheres to the carrier. This is probably because the chargeability of the toner has become uneven. In addition, since the strength of magnetization of the carrier exceeds 70 kAm ² / kg, it seems that the stress on the developer between the regulating blade 9 and the developing sleeve 8 is increased, and the deterioration of the carrier is further advanced.

  Further, although the spectral reflectance in the powder state was good, the a * b * of the image was slightly higher than Japan Color. This is considered to be because the transfer efficiency was lowered due to carrier deterioration at the time of printing 100,000 sheets, and as a result, the toner loading amount was lowered. In addition, the graininess of the image is slightly worse. This seems to be because the particle size of the carrier is larger than 70 μm.

As described above, in a two-component developer containing at least a toner and a carrier, the toner contains at least a binder resin and a colorant, and the spectral reflectance of the toner in a powder state is 380 to 20% or less in the range of 500 nm, 15% or less in the range of 500 nm, and 60% or more in the range of 620 to 780 nm. The carrier is coated with a resin and has a true specific gravity of 2.5 to 4.2 g. By using a two-component developer characterized by being a magnetic carrier of / cm ³ , it is required in the color reproduction range required in the photographic and graphic arts fields, graininess required in the photographic field, and in the POD field. It is possible to provide a two-component developer and a replenishment developer capable of achieving the above durability.

It is a schematic diagram of a spectral reflectance. It is a schematic diagram which shows an example of the image development apparatus of this invention. 6 is a schematic diagram of a surface modification device used in Toner Production Example 1. FIG. It is a graph which shows an example of a circularity measurement result. It is a graph which shows an example of a spectral reflectance measurement result.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Developing apparatus 2 Developing container 3 Developing chamber 4 Agitation chamber 5 1st conveyance screw (circulation means)
6 Second conveying screw (circulation means)
7 Partition 8 Developing sleeve (developer carrier)
8 'magnet roller 9 regulating blade (developer layer thickness regulating member)
10 Photosensitive drum (image carrier)
30 Main body casing 31 Cooling jacket 32 Dispersion rotor 33 Square disk 34 Liner 35 Classification rotor 36 Guide ring 37 Material input port 38 Material supply valve 39 Material supply port 40 Product discharge port 41 Product discharge valve 42 Product extraction port 43 Top plate 44 Fine powder Discharge unit 45 Fine powder discharge port 46 Cold air introduction port 47 First space 48 Second space 49 Surface modification zone 50 Classification zone 100 Developing device

Claims (6)

In a two-component developer containing at least a toner and a carrier,
The toner contains at least a binder resin, a colorant and a wax,
Spectral reflectance of the toner in the powder state, 20% or less in the range of 380 nm to 500nm, and 10% 500nm or less, is 60% or more in the range of 600nm to 780 nm,
The toner has one or more endothermic peaks at a temperature of 30 ° C. to 200 ° C. in the endothermic curve in the differential scanning calorimetry (DSC) measurement of the toner, and the peak temperature of the maximum endothermic peak is 55 to 140 ° C. Yes,
The two-component developer , wherein the carrier is a magnetic carrier having a resin component on the surface and a true specific gravity of 2.5 to 4.2 g / cm ³ . The volume distribution standard 50% particle size (D50) of the magnetic carrier is 15 to 70 μm, and the magnetization strength under a magnetic field of 1000 / 4π (kA / m) is 40 to 70 Am ² / kg. The two-component developer according to claim 1. The colorant, C. I. Pigment Red 3, 9, 48: 4, 104, 112, 144, 166, 168, 170, 177, 178, 220, 221, 254, C.I. I. Pigment orange 5, 34, 36, 61, 64, 67, C.I. I. Two-component developer according to claim 1 or 2, characterized in that it contains a pigment on one or more kinds selected from the group consisting of Pigment Yellow 83,139,153.   The two-component developer according to any one of claims 1 to 3, wherein the toner has an average circularity of 0.930 to 0.990. For developing in a two-component development method in which a developer for replenishment containing at least a toner and a carrier is developed while being replenished to a developing device, and an excess carrier inside the developing device is discharged from the developing device as needed. A developer for replenishment,
The replenishment developer contains a preparative toner also decreased relative to the carrier 1 part by weight the proportions of 2 to 50 parts by weight,
The carrier has a resin component on a surface, a true specific gravity of 2.5 to 4.2 g / cm ^3, Ri 50% particle diameter (D50) is 15 to 70μm der a volume basis, 1 000/4 [pi] ( kA / m) in a magnetic field of 40 to 70 Am ² / kg,
The toner contains at least a binder resin, a colorant and a wax ,
Spectral reflectance of the toner in the powder state, 20% or less in the range of 380 nm to 500nm, and 10% 500nm or less state, and are more than 60% in the range of 600 nm to 780 nm,
The toner has one or more endothermic peaks at a temperature of 30 ° C. to 200 ° C. in the endothermic curve in the differential scanning calorimetry (DSC) measurement of the toner, and the peak temperature of the maximum endothermic peak is 55 to 140 ° C. replenishing developing agent characterized Rukoto Oh. The colorant is C.I. I. Pigment Red 3, 9, 48: 4, 104, 112, 144, 166, 168, 170, 177, 178, 220, 221, 254, Pigment Orange 5, 34, 36, 61, 64, 67, C.I. I. The replenishment developer according to claim 5 , comprising at least one pigment selected from the group consisting of CI Pigment Yellow 83, 139, and 153.

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