JP2006091439A - Electrostatic charge image developing carrier and electrostatic charge image developer using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrostatic charge image developing carrier having excellent fluidity and capable of forming a uniform mixture state with toner and the carrier in a short time even when the toner is frequently supplied into a developer, and to provide an electrostatic charge image developer using the above electrostatic charge image developing carrier. <P>SOLUTION: The electrostatic charge image developing carrier used shows the average shape factor SF-1 obtained by using an image processing analyzer in the range of 1.00≤(SF-1)≤1.35 and shows the 10% shape factor SF-1 in the range of (10%SF-1)≤1.60. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a carrier for an electrostatic charge image developer for developing an electrostatic latent image by use in electrophotography, electrostatic recording method, and the like, and an electrostatic charge image developer using the same.

  A two-component development method comprising a carrier and a toner is currently widely used because it is relatively easy to control toner charging and form a developer layer, and can cope with higher speeds. In the two-component development method, the mixing property of the toner and the carrier is very important for stabilizing the quality of the printed matter. In particular, in a high-speed machine that prints at a printing speed exceeding 20 m / min, the mixing property of toner and carrier is important. Since a high-speed machine consumes a large amount of toner in a short time, the toner is frequently replenished in the developer. At that time, the toner needs to be in a predetermined charged state instantaneously. For that purpose, when the toner is replenished in the developer and comes into contact with the carrier, it is necessary to obtain a uniform mixed state in a very short time. If the mixed state is non-uniform, the charge amount of the toner becomes non-uniform, and problems such as fogging and bethamra occur on the printed matter. In addition, contamination in the machine with toner having a poor rise in charge becomes significant, which is a problem.

  As a technique for solving the above-described problem, it has been reported that the average shape factor SF-1 of the carrier is set within a certain range (spherical or substantially spherical) to improve the fluidity of the developer (for example, Patent Documents). 1). By doing so, the ability of the toner to impart triboelectric charge is increased, and the shape of the magnetic brush at the developing pole is made uniform, so that a high-quality image can be obtained. Further, the flowability of the developer can be improved by setting the average shape factor SF-1 of the toner particles and the average shape factors SF-1 and SF-2 of the carrier particles within a certain range (spherical or substantially spherical). It has been reported that it can be performed (for example, refer to Patent Document 2). In these techniques, the sphericity of the carrier is regarded as the average shape factor SF-1, and the fluidity of the developer is ensured by making this a certain range. However, there are variations in the shape of the carrier particles. Even if the average shape factor SF-1 is set within a certain range, it is an average value and does not measure variation (distribution). Therefore, the above publication using a carrier defined only by the average shape factor SF-1 has characteristics required for developers used in printers having various development speeds ranging from low speeds to high speeds, that is, rising of charging. The technique for obtaining an excellent electrostatic image developer exhibiting excellent and stable charging characteristics and good fog and bethamra is not sufficiently disclosed, and further improvement is required from a practical viewpoint.

  By the way, a binder resin and a colorant are mixed in an organic solvent, and this is kneaded wet to produce a mixed solution in which the binder resin and the colorant are dissolved or dispersed in the organic solvent. The fine particles of the mixed solution are produced by emulsification in an aqueous medium, and further, resin fine particles in which a colorant is dispersed in the binder resin are produced by removing the organic solvent, and then the resin fine particles are separated from the aqueous medium. A method of manufacturing a spherical toner by drying is known (see, for example, Patent Document 3). However, this technology does not disclose anything about the technology relating to the carrier shape factor SF-1 and the technology for improving the mixing property of the toner and the carrier.

JP 2000-39742 (28th and 29th paragraphs) JP 2001-201893 (Claims, 7th and 8th paragraphs) JP 2004-54175 A (paragraphs 100 and 137, Examples)

  Accordingly, an object of the present invention is to develop an electrostatic charge image that has excellent fluidity and can evenly mix toner and carrier in a short time even when the toner is frequently replenished in the developer. It is to provide a carrier for a medicine. Another object of the present invention is to provide an electrostatic image developer using an electrostatic image developer carrier that solves the above problems.

  As described above, it is described in the prior art that the flowability of the developer can be improved by using a spherical carrier defined by the average shape factor SF-1. The present inventors also examined various spherical carriers. However, even if the average shape factor SF-1 is set to a value closer to a sphere (1.00), a carrier having excellent fluidity cannot always be obtained. Examining in more detail, it was found that even if the average shape factor SF-1 is a small value (a value close to 1.00), if a large number of irregularly shaped carrier particles are present, the carrier has poor overall fluidity. The present inventors have found that the presence ratio of irregularly shaped carrier particles (carrier particles having a large SF-1 value) is important in addition to the average shape factor SF-1 as a factor affecting the fluidity of the carrier. The present invention has been completed.

That is, in the present invention, the value of the average shape factor SF-1 obtained by using the image processing analysis apparatus is
1.00 ≦ average shape factor SF-1 ≦ 1.35
And the value of the 10% shape factor SF-1 is
10% SF-1 ≦ 1.60
A carrier for an electrostatic charge image developer is provided.

  The present invention also provides an electrostatic image developer comprising the above-mentioned carrier for electrostatic image developer and toner.

  Since the carrier for an electrostatic charge image developer of the present invention is excellent in fluidity, the toner and the carrier become uniform in a short time even when the toner is supplied to the electrostatic charge image developer using the same. Can be instantaneously set to a predetermined charged state. Therefore, the electrostatic charge image developer using the carrier for electrostatic charge image developer of the present invention has a fast charge rise and charging characteristics and image characteristics that do not cause defects such as fogging and bethamra on the printed matter. It becomes a developer excellent in. In particular, it is excellent as a carrier for an electrostatic charge image developer used in a high-speed machine that prints at a printing speed exceeding 20 m / min.

The average shape factor SF-1 and the 10% shape factor SF-1 obtained using the image processing analyzer are values defined below.
(1) Shape factor SF-1
The shape factor SF-1 is an index representing the shape of an individual carrier. An arbitrary carrier 1 is selected from carrier particles captured by a CCD camera using a device in which a CCD camera (manufactured by Sony Corporation) is connected to a Luzex AP. This is a value calculated by the following equation after selecting the image and analyzing this using an image processing analyzer LuzexAP manufactured by Nireco.

上記式中、
ＭＸＬＮＧ；キャリア粒子の最大径
ＡＲＥＡ ；キャリア粒子の投影面積
をそれぞれ表す。

In the above formula,
MXLNG; carrier particle maximum diameter AREA; carrier particle projected area.

(2) Average shape factor SF-1
The average shape factor SF-1 is a value obtained by obtaining the shape factor SF-1 of 100 carrier particles by the above method and averaging them.

(3) 10% shape factor SF-1
The 10% shape factor SF-1 has the largest shape factor SF-1 when the shape factor SF-1 of 100 carrier particles is obtained by the above method and arranged in the descending order of the shape factor SF-1. This is the value of the shape factor SF-1 of the carrier located at 10% of the number of measured carriers counted from the carrier.

  In the electrostatic charge image developer carrier of the present invention, the average shape factor SF-1 is preferably 1.00 ≦ average shape factor SF-1 ≦ 1.30, and the 10% shape factor SF-1 is It is preferable that 10% SF-1 ≦ 1.50, and it is more preferable that 10% SF-1 ≦ 1.45. Within the above range, the carrier for an electrostatic charge image developer of the present invention is more excellent in fluidity.

  The value of the 20% shape factor SF-1 is preferably 20% SF-1 ≦ 1.50, and the value of the 30% shape factor SF-1 is 30% SF-1 ≦ 1.40. It is preferable. Note that the 20% shape factor SF-1 is the same as that for obtaining the 10% shape factor SF-1, and the shape factor SF-1 of 100 carrier particles is obtained and arranged in descending order of the shape factor SF-1. Sometimes it is the value of the shape factor SF-1 of the carrier located at 20% of the number of measured carriers, counting from the carrier having the largest shape factor SF-1. Further, the 30% shape factor SF-1 is obtained from the carrier having the largest shape factor SF-1 when the shape factor SF-1 of 100 carrier particles is obtained and arranged in the descending order of the shape factor SF-1. This is the value of the shape factor SF-1 of the carrier located at 30% of the number of measured carriers.

  The core material of the carrier is a metal such as iron, magnetite, ferrite, nickel, cobalt, etc. used in the usual two-component development system, and these metals and zinc, antimony, aluminum, lead, tin, bismuth, beryllium, manganese, selenium, tungsten Alloys or mixtures with metals such as zirconium and vanadium, metal oxides such as iron oxide, titanium oxide and magnesium oxide, nitrides such as chromium nitride, nitrides such as vanadium nitride, carbides such as silicon carbide and tungsten carbide, and ferromagnetic materials Ferrite, a mixture thereof, and the like can be used. Among them, ferrite or magnetite having a low true specific gravity, high resistance, excellent environmental stability, and easy to form into a spherical shape is preferably used. In particular, it is preferable to use magnetite as the core material of the carrier for an electrostatic charge image developer of the present invention in which the average shape factor SF-1 and the 10% shape factor SF-1 are in a specific numerical range. The average particle diameter is generally 10 to 500 μm, but 30 to 100 μm is preferable for printing a high resolution image.

  Examples of coating resins for coating these core materials include polyethylene, polypropylene, polystyrene, polyacrylonitrile, polyvinyl acetate, polyvinyl alcohol, polyvinyl butyral, polyvinyl chloride, polyvinyl carbazole, polyvinyl ether polyvinyl ketone, vinyl chloride / vinyl acetate. Copolymers, styrene / acrylic copolymers, straight silicone resins composed of organosiloxane bonds or modified products thereof, fluororesins, (meth) acrylic resins, polyesters, polyurethanes, polycarbonates, phenol resins, amino resins, melamine resins, benzoguanamine resins Urea resin, amide resin, epoxy resin and the like can be used. Among these, silicone resin, fluororesin, and (meth) acrylic resin are particularly excellent in charging stability and coating strength, and can be used more suitably.

  As a resistance control agent dispersed in the above resin, carbon black such as acetylene black, channel black, furnace black, metal carbide such as SiC, TiC, metal nitride such as BN, NbN, TiN, MoB, CrB, Metal borides such as TiB2, metal oxides such as ZnO, PiO2 and SnO2, and metal fine powders such as Al and Ni can be used. The number average diameter of the resistance control agent is 0.01 to 5 μm, preferably about 0.05 to 3 μm. This is measured with a transmission electron microscope.

  The method of coating the resin on the surface of the core material is not particularly selected, but the immersion method in which the resin is coated in the coating resin solution, the spray method in which the coating resin solution is sprayed on the surface of the core material, or the carrier is floated by flowing air. Examples thereof include a fluidized bed method in which spraying is performed in a state where the core material is coated and a kneader coater method in which a core material and a coating resin solution are mixed in a kneader coater to remove the solvent.

  The solvent used in the coating resin solution is not particularly limited as long as it dissolves the coating resin. For example, toluene, xylene, acetone, methyl ethyl ketone, tetrahydrofuran, dioxane and the like can be used. The thickness of the coating layer on the carrier surface is usually 0.1 to 3.0 μm.

  When an electrostatic charge image developer is prepared using the electrostatic charge image developer carrier of the present invention, the blending amount of the electrostatic charge image developer carrier and the toner is not particularly limited. The toner is 0.5 to 15 parts by mass per part by mass.

The method for producing the carrier for an electrostatic charge image developer of the present invention is not particularly limited, but examples are shown below.
The spheroidization treatment of the core material can be performed by a conventionally known surface polishing method, for example, an electrolytic polishing method, a chemical polishing method, or the like, using a mechanical polishing method using a stirring mixer or a pulverizer. Can be manufactured. Examples of the stirring mixer that can be used for the spheroidizing treatment include a Henschel mixer, a super mixer, and an attritor. Examples of the pulverizer include a jet mill, a pin mill, KTM, and AFG.

As a preferable method for producing the carrier for an electrostatic charge image developer of the present invention, for example, a carrier core is put into a Henschel mixer (made by Mitsui Mining Co., Ltd.) with ST / A ₀ blades set, and the tip of the deflector blade is a Henschel wall surface. There is a method in which the deflector is set so as to come to a position of 2 to 15 mm, then water is passed through the wall surface of the Henschel mixer, and mixing is performed at 1000 to 3000 rpm. In order to remove fine particles from the mixed carrier particles, it is desirable to sieve using a sieve having an opening of about 40 to 60 μm. The values of the average shape factor SF-1 and the 10% shape factor SF-1 are adjusted by appropriately selecting and adjusting the above-described model for spheroidization processing and each condition. After the spheronization treatment, the surface of the core material is coated with a resin by a spray drying method or the like as necessary.

  As the binder resin of the toner used in the present invention, it can be used without particular limitation as long as it is generally used as a binder resin in the toner. For example, polystyrene, styrene- (meth) Acrylic ester copolymers, olefin resins, polyester resins, amide resins, carbonate resins, epoxy resins, graft polymers thereof, and mixtures thereof can be raised.

  Among them, polyester resin, styrene- (meth) acrylic acid in consideration of charging stability, storage stability, fixing characteristics, or color reproducibility when used as a color toner resin containing chromatic organic pigments, etc. Ester copolymer resins can be suitably used.

  The polyester resin is obtained, for example, by dehydrating and condensing a dicarboxylic acid and a diol by an ordinary method. Examples of the dicarboxylic acid include phthalic anhydride, terephthalic acid, isophthalic acid, orthophthalic acid, adipic acid, maleic acid, maleic anhydride, fumaric acid, itaconic acid, citraconic acid, hexahydrophthalic anhydride, tetrahydrophthalic anhydride, and cyclohexanedicarboxylic acid. Examples thereof include dicarboxylic acids such as acid, succinic acid, malonic acid, glutaric acid, azelaic acid, and sebacic acid, or derivatives thereof.

  Examples of the diol include ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, butanediol, pentanediol, hexanediol, bisphenol A, and polyoxyethylene- (2.0) -2,2-bis. (4-hydroxyphenyl) propane and derivatives thereof, polyoxypropylene- (2.0) -2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene- (2.2) -polyoxyethylene- (2 .0) -2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene- (6) -2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene- (2.2) -2, 2-bis (4-hydroxyphenyl) propane, poly Oxypropylene- (2.4) -2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene- (3.3) -2,2-bis (4-hydroxyphenyl) propane and its derivatives, etc. Can be mentioned.

  Furthermore, diols such as polyethylene glycol, polypropylene glycol, ethylene oxide-propylene oxide random copolymer diol, ethylene oxide-propylene oxide block copolymer diol, ethylene oxide-tetrahydrofuran copolymer diol, polycaprocactone diol, etc. Can also be used.

  Further, if necessary, for example, a trifunctional or higher functional aromatic carboxylic acid such as trimellitic acid, trimellitic anhydride, pyromellitic acid, pyromellitic anhydride or a derivative thereof, or sorbitol, 1,2,3,6- Hexanetetraol, 1,4-sorbitan, pentaerythritol, 1,2,4-butanetriol, 1,2,5-pentanetriol, glycerin, 2-methylpropanetriol, 2-methyl-1,2,4-butane Triol, trimethylolethane, trimethylolpropane, 1,3,5-trimethylolbenzene or other trifunctional alcohol or more, or bisphenol A type epoxy resin, bisphenol F type epoxy resin, ethylene glycol diglycidyl ether, hydroquinone di Glycidyl ether, N, N-jig Cidylaniline, glycerin triglycidyl ether, trimethylolpropane triglycidyl ether, trimethylolethane triglycidyl ether, pentaerythritol tetraglycidyl ether, cresol novolac type epoxy resin, phenol novolac type epoxy resin, polymer of vinyl compound having epoxy group, Alternatively, a trifunctional or higher polyhydric epoxy compound such as a copolymer, an epoxidized resorcinol-acetone condensate, a partially epoxidized polybutadiene, or one or more of semi-dry or dry fatty acid ester epoxy compounds may be used in combination.

  The polyester resin can be obtained by performing a dehydration condensation reaction or a transesterification reaction using the above raw material components in the presence of a catalyst. The reaction temperature and reaction time at this time are not particularly limited, but are usually 150 to 300 ° C. and 2 to 24 hours.

  As a catalyst for performing the above reaction, for example, zinc oxide, stannous oxide, dibutyltin oxide, dibutyltin dilaurate, or the like can be appropriately used.

The polyester resin only needs to have an appropriate glass transition point and melt viscosity characteristics as a toner for two-component development, and a temperature at which the viscosity becomes 1 × 10 ⁵ poise is 95 ° C. or higher has good fixability. in preferred, among them, more preferable because fixability good at low temperatures as the temperature at which the viscosity of 1 × 10 ⁵ poise ninety-five to one hundred and seventy ° C., the temperature at which its viscosity is 1 × 10 ⁵ poise 95 The thing of 160 degreeC is especially preferable.

On the other hand, the glass transition temperature (Tg) is preferably 40 [deg.] C. or higher, and particularly preferably the glass transition temperature (Tg) is 45 to 85 [deg.] C.
Further, the acid value is preferably 30 or less, and particularly preferably 10 or less. If the acid value is too high, the charge amount is lowered and the desired charge amount cannot be obtained.

  Examples of the styrene monomer used for the copolymer resin of styrene- (meth) acrylic acid ester include styrene, α-methylstyrene, vinyltoluene, p-sulfonestyrene, dimethylaminomethylstyrene, and the like.

  Examples of (meth) acrylic acid ester monomers include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, and isobutyl (meth) acrylate. , Alkyl (meth) acrylates such as tertiary butyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate; fats such as cyclohexyl (meth) acrylate Cyclic (meth) acrylates; aromatic (meth) acrylates such as benzyl (meth) acrylate; hydroxyl-containing (meth) acrylates such as hydroxyethyl (meth) acrylate; (meth) acryloxyethylene Phosphoric acid group-containing (meth) acrylates such as ruphosphate; halogen atom-containing (meta) such as 2-chloroethyl (meth) acrylate, 2-hydroxy 3-chloropropyl (meth) acrylate and 2,3-dibromopropyl (meth) acrylate ) Acrylate; epoxy group-containing (meth) acrylate such as glycidyl (meth) acrylate; ether group-containing (meth) acrylate such as 2-methoxyethyl (meth) acrylate and 2-ethoxyethyl (meth) acrylate; dimethylaminoethyl (meth) ) Acrylate, basic nitrogen atom such as diethylaminoethyl (meth) acrylate or amide group-containing (meth) acrylate;

  Moreover, the unsaturated compound copolymerizable with these can also be used as needed. For example, a carboxyl group-containing vinyl monomer such as (meth) acrylic acid, itaconic acid, crotonic acid, maleic acid, fumaric acid; a sulfo group-containing vinyl monomer such as sulfoethylacrylamide; a nitrile group-containing vinyl monomer such as (meth) acrylonitrile; Ketone group-containing vinyl monomers such as vinyl methyl ketone and vinyl isopropenyl ketone; basic such as N-vinyl imidazole, 1-vinyl pyrrole, 2-vinyl quinoline, 4-vinyl pyridine, N-vinyl 2-pyrrolidone, N-vinyl piperidone Nitrogen atom or amide group-containing vinyl monomers can be used.

  Moreover, you may use a crosslinking agent in 0.1-2 mass% with respect to the said vinyl monomer. Examples of the crosslinking agent include divinylbenzene, divinylnaphthalene, divinyl ether, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, 1, 3-butylene glycol di (meth) acrylate, 1,6-hexane glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, propylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, polypropylene glycol Examples include di (meth) acrylate, trimethylolpropane tri (meth) acrylate, and tetramethylolmethane tetra (meth) acrylate.

  Or in resin using the copolymer of the styrene- (meth) acrylic acid ester copolymerized with the said carboxyl group-containing vinyl monomer, it can also be set as crosslinked resin using a metal salt. As metal salts, halides such as Al, Ba, Ca, Cd, Co, Cr, Cu, Fe, Hg, Mg, Mn, Ni, Pb, Sn, Sr, Zn, hydroxide, oxide, carbonate, There are carboxylates, alkoxylates, chelate compounds and the like. The crosslinking reaction can be performed by heating and stirring in the presence of a solvent.

  As a method for producing a copolymer of styrene- (meth) acrylic acid ester, a usual polymerization method can be adopted, and a polymerization reaction is carried out in the presence of a polymerization catalyst such as solution polymerization, suspension polymerization, bulk polymerization and the like. Is mentioned.

Examples of the polymerization catalyst include 2,2′-azobis (2,4-dimethylvaleronitrile), 2,2′-azobisisobutyronitrile, 1,1′-azobis (cyclohexane-1-carbonitrile), Examples thereof include benzoyl peroxide, dibutyl peroxide, butyl peroxybenzoate, and the amount used is preferably 0.1 to 10.0% by mass of the vinyl monomer component.
As a copolymer resin of styrene- (meth) acrylic acid ester, it is sufficient that it has an appropriate glass transition point and melt viscosity characteristics as a two-component developing toner, and the temperature at which the viscosity becomes 1 × 10 ⁵ poise. However, those having a viscosity of 1 × 10 ⁵ poise are preferably 95 to 170 ° C. because the fixability at low temperatures is also good, and the viscosity is preferably A temperature of 1 to 10 ⁵ poise is particularly preferably 95 to 160 ° C.

On the other hand, the glass transition temperature (Tg) of the copolymer resin of styrene- (meth) acrylic acid ester is preferably 40 ° C. or higher, and particularly preferably the Tg is 45 to 85 ° C.
Further, the acid value is preferably 30 or less, and particularly preferably 15 or less. If the acid value is too high, the charge amount is lowered and the desired charge amount cannot be obtained.

  As the colorant, for example, carbon black, various organic pigments, inorganic pigments, dyes, and the like are used, and are not particularly limited, but examples thereof include the following.

  Examples of the colorant used for the toner include known ones. Carbon blacks such as furnace black, channel black, acetylene black, thermal black, lamp black, etc. classified by the production method are used as black colorants, and phthalocyanine C.I. I. Pigment Blue 15-3, Indanthrone C.I. I. Pigment Blue 60 and the like are quinacridone C.I. I. Pigment Red 122, an azo-based C.I. I. Pigment Red 22, C.I. I. Pigment Red 48: 1, C.I. I. Pigment Red 48: 3, C.I. I. Pigment Red 57: 1 and the like are azo-based C.I. I. Pigment Yellow 12, C.I. I. Pigment Yellow 13, C.I. I. Pigment Yellow 14, C.I. I. Pigment Yellow 17, C.I. I. Pigment Yellow 97, C.I. I. Pigment Yellow 155, an isoindolinone-based C.I. I. Pigment Yellow 110, a benzimidazolone-based C.I. I. Pigment Yellow 151, C.I. I. Pigment Yellow 154, C.I. I. Pigment Yellow 180, C.I. I. Pigment Yellow 185 and the like. Content of a coloring agent exists in the range of 1 mass part to 20 mass parts. These colorants can be used alone or in combination of two or more. The weight ratio between the resin and the colorant is not particularly limited, but is usually 1 to 30 parts by weight, preferably 1 to 10 parts by weight per 100 parts by weight of the resin. In order to produce a color toner using the chromatic colorant, it is desirable to use a polyester resin from the viewpoint of excellent color image colorability and transparency. The polyester resin is more tough than the styrene acrylic resin, has a characteristic of resisting stress in the developing apparatus, and has a low melting point, and is suitable as a resin for color toner.

  A known charge control agent can be used for the toner as needed. For example, as a positive charge control agent, a nigrosine dye, a modified nigrosine dye, a triphenylmethane dye, a resin containing a quaternary ammonium salt, a quaternary ammonium group and / or an amino group can be used, and as a negative charge control agent Is trimethylethane dye, metal salt or complex of salicylic acid, metal salt or complex of benzyl acid, copper phthalocyanine, perylene, quinacridone, metal salt or complex of azo compound, calixarene type phenolic condensate, cyclic polysaccharide, carboxyl Resins containing groups and / or sulfonyl groups, etc. can be used. The content of the charge control agent is preferably 0.3 to 10 parts by mass, more preferably 1 to 5 parts by mass per 100 parts by mass of the binder resin.

Further, in heat roll fixing applications, various waxes are used as needed as an auxiliary agent for enhancing the release effect for the purpose of preventing troubles caused by toner heat roll adhesion contamination (offset). Such natural waxes, high-pressure polyethylene, and polyolefin waxes such as polypropylene can be used. Carnauba wax, montan ester wax, rice wax and / or scale insect wax are particularly preferably used. These waxes show the best dispersibility in the polyester resin, and the improvement in fixing property and offset resistance is remarkable.
As the carnauba wax, it is preferable to use a free fatty acid type carnauba wax from which free fatty acids have been removed by purification. The acid value of the de-free fatty acid type carnauba wax is preferably 8 or less, more preferably 5 or less. The de-free fatty acid type carnauba wax becomes microcrystalline than the conventional carnauba wax and the dispersibility in the polyester resin is improved. The montan ester wax is refined from minerals, and by refining, it becomes microcrystals similar to carnauba wax and the dispersibility in the polyester resin is improved. In the case of montan ester wax, the acid value is particularly preferably 30 or less. The rice wax is obtained by purifying rice bran wax, and the acid value is preferably 13 or less. The scale insect wax can be obtained by, for example, dissolving a waxy component secreted by a scale larva of a scale insect (also known as scallop) in hot water, separating the upper layer and cooling and solidifying, or repeating the process. The scale insect wax purified by such means is white in the solid state and exhibits an extremely sharp melting point, which is suitable as a toner wax in the present invention. The acid value is 10 or less by purification, and 5 or less is preferable for toner.
The above waxes may be used alone or in combination. Good fixing offset performance can be obtained by adding 0.3 to 15 parts by mass, preferably 1 to 5 parts by mass with respect to the binder resin. If the amount is less than 0.3 parts by mass, the offset resistance is impaired. If the amount is more than 15 parts by mass, the fluidity of the toner is deteriorated, and spent carrier is generated by adhering to the carrier surface, which adversely affects the charging characteristics of the toner. Will give.
In addition to the above natural waxes, synthetic ester waxes can also be suitably used. Among synthetic ester waxes, there is Elktor WEP-5 (manufactured by NOF Corporation). Synthetic waxes such as polypropylene wax and polyethylene wax can also be used in combination.

  The toner of the present invention can be used as either a pulverized toner or a chemical toner regardless of a specific production method. The pulverized toner can be obtained by melting and kneading a resin and a colorant at a temperature equal to or higher than the melting point (softening point) of the resin, pulverizing, and classifying.

  Specifically, for example, the resin and the colorant are mixed as essential components by a kneading means such as a two-roll, three-roll, pressure kneader, or twin-screw extruder. At this time, the colorant only needs to be uniformly dispersed in the resin, and the melt kneading conditions are not particularly limited, but are usually 80 to 180 ° C. for 30 seconds to 2 hours. As the colorant, a masterbatch that is previously flushed so as to be uniformly dispersed in the resin or melt-kneaded with the resin at a high concentration may be used.

  Then, after cooling it, a method of pulverizing with a pulverizer such as a jet mill and classifying with an air classifier or the like can be mentioned.

  The chemical toner can be obtained by a suspension polymerization method, an emulsion polymerization method, a phase inversion emulsification method or the like. The phase inversion emulsification method is a method in which a binder resin and a colorant are mixed in an organic solvent and kneaded in a wet manner to produce a mixed solution in which the binder resin and the colorant are dissolved or dispersed in the organic solvent. Next, the mixed solution is emulsified in an aqueous medium to produce fine particles of the mixed solution. Further, by removing the organic solvent, resin fine particles in which a colorant is dispersed in the binder resin are produced. Is produced by separating the toner from the aqueous medium and drying it. In this case, in addition to the binder resin and the colorant, if necessary, a release agent, a charge control agent, or the like may be added to perform the dispersion step. In addition, each raw material may be separately subjected to dispersion treatment.

  Further, among the phase inversion emulsification methods, after forming fine particles of a mixed solution containing a binder resin, a colorant and the like and an organic solvent in an aqueous medium, the fine particles are aggregated by combining the fine particles. It is particularly preferable to produce a toner by performing a forming step (unifying step) and then separating the aggregate from the aqueous medium. By such a production method, there is no emulsification loss, the particle size distribution is sharp, and a spherical or potato-like toner can be obtained simply and in a short time with a high yield.

  The average particle diameter of the particles constituting the toner base is not particularly limited, but is usually adjusted to 5 to 15 μm.

  Usually, an external additive is mixed with the toner base thus obtained using a mixer such as a Henschel mixer.

External additives are used for surface modification of a toner base such as improvement of toner fluidity and charging characteristics, and include inorganic fine powders such as silicon dioxide, titanium oxide, and alumina, and hydrophobic substances such as silicone oil. A surface treated with a chemical treatment agent, a resin fine powder, or the like is used.
Examples of silica include those having hydrophobicity among silicon dioxide, and those obtained by surface-treating silicon dioxide with various polyorganosiloxanes and silane coupling agents. For example, there are those marketed under the following trade names.
AEROSIL R972, R974, R202, R805, R812
RX200, RY200, R809, RX50,
RA200HS, RA200H
[Nippon Aerosil Co., Ltd.]
WACKER HDK H2000, H2050EP
HDK H3050EP, HVK2150
[Wacker Chemicals East Asia Co., Ltd.]
Nipsil SS-10, SS-15, SS-20, SS-50,
SS-60, SS-100, SS-50B, SS-50F,
SS-10F, SS-40, SS-70, SS-72F,
[Nippon Silica Industry Co., Ltd.]
CABOSIL TG820F
[Cabot Specialty Chemicals, Inc.]
The use ratio of the external additive is usually 0.05 to 5% by mass, preferably 0.1 to 3% by mass with respect to the toner base.

  These silicas may be used in combination of two or more of different average particle sizes. The proportion of silica used is usually 0.05 to 5% by mass, preferably 0.1 to 3% by mass, based on the toner base.

  EXAMPLES Next, although an Example demonstrates this invention in detail, this invention is not limited to these. In the following examples and comparative examples, “%” represents “% by mass” unless otherwise specified.

<Preparation of powder toner>
(Resin synthesis example 1)
Terephthalic acid 2.0 mol parts Isophthalic acid 2.5 mol parts Trimellitic acid 0.5 mol parts Polyoxyethylene- (2.0) -2,2
-Bis (4-hydroxyphenyl) propane 4.0 mol part Ethylene glycol 1.2 mol part is put into a four-necked flask set with a stirrer, condenser and thermometer, and under a nitrogen gas stream, all acid components 0.07 parts by mass of dibutyltin oxide was added, and the reaction was carried out at 220 ° C. for 15 hours while removing water produced by dehydration condensation. The obtained polyester resin had a softening temperature of 155 ° C. by a ring and ball softening point measurement method, a Tg of 62 ° C. by an DSC method, and an acid value of 10.
(Resin synthesis example 2)
Styrene 320 parts by weight Butyl acrylate 60 parts by weight Methacrylic acid 20 parts by weight Azobisisobutyronitrile 4 parts by weight Xylene 600 parts by weight

Was put in a round bottom flask, reacted at 80 ° C. for about 10 hours in a nitrogen gas atmosphere, and then heated to 130 ° C. to complete the polymerization. Thereafter, 12 parts by mass of aluminum isopropoxide was added and allowed to react for about 1 hour, and then the mixture was heated to 180 ° C. and reduced to 0.5 mmHg with a vacuum pump to remove the solvent.

  The resulting chelate-crosslinked styrene acrylic resin had a softening temperature of 145 ° C. by a ring and ball softening point measurement method, a Tg of 61 ° C. by an DSC method, and an acid value of 5.

(Toner Production Example 1)
Resin of Resin Synthesis Example 1 91 parts by mass Carbon black 5 parts by mass “Mogal L (manufactured by Cabot Specialty Chemicals, Inc.)”
Biscol 550P (manufactured by Sanyo Chemical Co., Ltd.) 2 parts by mass Charge control agent (positive charge control agent)
2 parts by mass of “Bontron N-07 (manufactured by Orient Chemical Co., Ltd.)” is mixed with a Henschel mixer and kneaded with a biaxial kneader. The kneaded material thus obtained was pulverized and classified to obtain “toner base A” having a volume average particle size of 10.1 microns.

-"Toner base A" 100 parts by mass Silica HDK3050EP (Wacker Chemicals) After mixing parts by mass with a Henschel mixer, toner A was obtained through a sieve.

(Toner Production Example 2)
Resin synthesis example 1 91% by mass
Carbon black Carbon black 5 parts by mass “Mogal L (manufactured by Cabot Specialty Chemicals, Inc.)”
Biscol 550P (manufactured by Sanyo Chemical Co., Ltd.) 2 parts by mass Charge control agent (negative charge control agent)
2 parts by mass of “Bontron N-07 (manufactured by Orient Chemical Co., Ltd.)” is mixed with a Henschel mixer and kneaded with a biaxial kneader. The kneaded material thus obtained was pulverized and classified to obtain “toner base B” having a volume average particle size of 10.1 microns.

-"Toner base B" 100 parts by mass-Silica HDK H2000 (Wacker Chemicals Co., Ltd.) 1 part by mass was mixed with a Henschel mixer, and toner B was obtained through a sieve.

(Toner Production Example 3)
Resin of resin synthesis example 2 91% by mass
5 parts by mass of carbon black “Mogal L (manufactured by Cabot Specialty Chemicals, Inc.)”
Biscol 550P (manufactured by Sanyo Chemical Co., Ltd.) 2 parts by mass Charge control agent (negative charge control agent)
2 parts by mass of “Bontron N-07 (manufactured by Orient Chemical Co., Ltd.)” is mixed with a Henschel mixer and kneaded with a biaxial kneader. The kneaded material thus obtained was pulverized and classified to obtain “toner base C” having a volume average particle size of 10.1 microns.

-"Toner base C" 100 parts by mass-Silica HDK H2000 (Wacker Chemicals) 1 part by mass was mixed with a Henschel mixer, and then toner C was obtained through a sieve.

<Production of chemical toner>
(1) Synthesis of polyester resin Trimellitic anhydride (TMA) as polyvalent carboxylic acid, terephthalic acid (TPA), isophthalic acid (IPA) as divalent carboxylic acid, polyoxypropylene (2.4)-as aromatic diol 2,2-bis (4-hydroxyphenyl) propane (BPA-PO), polyoxyethylene (2.4) -2,2-bis (4-hydroxyphenyl) propane (BPA-EO), ethylene as an aliphatic diol Glycol (EG) is used in each molar composition ratio shown in Table 1, and tetrabutyl titanate is charged as a polymerization catalyst into a separable fresco at 0.3% by mass with respect to the total monomer amount. Attach a condenser and a nitrogen inlet tube and heat at 220 ° C for 15 hours in an electric heating mantle heater under normal pressure nitrogen flow. After the reaction, the pressure was reduced successively and the reaction was continued at 10 mmHg. The reaction was followed by a softening point according to ASTM E28-517. When the softening point reached a predetermined temperature, the vacuum was stopped and the reaction was terminated. Table 1 shows the composition and physical property values (characteristic values) of the synthesized resin.

ＴＭＡ；無水トリメリット酸
ＴＰＡ；テレフタル酸
ＩＰＡ；イソフタル酸
ＢＰＡ−ＰＯ；ポリオキシプロピレン（２．４）−２，２−ビス（４−ヒドロキシフェニル）プロパン
ＢＰＡ−ＥＯ；ポリオキシエチレン（２．４）−２，２−ビス（４−ヒドロキシフェニル）プロパン
ＥＧ；エチレングリコール
ＦＴ値；フローテスター値

TMA; trimellitic anhydride TPA; terephthalic acid IPA; isophthalic acid BPA-PO; polyoxypropylene (2.4) -2,2-bis (4-hydroxyphenyl) propane BPA-EO; polyoxyethylene (2.4 ) -2,2-bis (4-hydroxyphenyl) propane EG; ethylene glycol FT value; flow tester value

The softening point of the resin is defined by a T1 / 2 temperature measured using a flow tester CFT-500 manufactured by Shimadzu Corporation, which is a constant load extrusion type capillary rheometer. The measurement conditions with a flow tester were: piston cross-sectional area 1 cm ² , cylinder pressure 0.98 MPa, die length 1 mm, die hole diameter 1 mm, measurement start temperature 50 ° C., temperature rise rate 6 ° C / min, sample weight 1. It carried out on the conditions of 5g. The glass transition temperature “Tg” (° C.) is an onset value measured at a rate of temperature increase of 10 ° C. per minute by the second run method using a differential scanning calorimeter (DSC-50) manufactured by Shimadzu Corporation. .

(2) Preparation Example of Release Agent Dispersion Liquid Carnauba wax “Carnauba Wax No. 1” (Yoko Kato imported product) 30 parts and polyester resin (R1 in Table 1) 70 parts were kneaded with a pressure kneader, and then the kneaded product And 185 parts of methyl ethyl ketone were charged into a ball mill, stirred for 6 hours, and then taken out. The solid content was adjusted to 35% by mass to obtain a fine dispersion (W1) of a release agent.

(3) Preparation Example of Colorant Master In the formulation shown in Table 2, a mixture of a color pigment, a resin (R1 in Table 1) and methyl ethyl ketone was pre-dispersed with Desper, and then an Eiger Motor Mill (manufactured by Eiger, USA: M-1000 ) To prepare a colorant master solution. The solid content was adjusted to 30% by mass with methyl ethyl ketone to prepare a P2 colorant master solution. For P1, pigment dispersion was performed using a kneader with the composition shown in Table 2 to prepare a carbon black colorant master chip.

(Preparation of mill base)
The release agent dispersion, colorant dispersion, dilution resin (additional resin), and methyl ethyl ketone were mixed with a desper to prepare mill bases (MB1 to MB2). Table 3 shows the formulation of the produced mill base. Bontron N-24 (manufactured by Orient Chemical) was used for CCA.

  The acid value was measured according to JIS K6901, and Tg was measured according to JIS K7121.

(Toner Production Example 4)
Charge 545 parts of mill base MB1 to a cylindrical 2 L separable flask having a Max Blend blade as a stirring blade, then add 71.6 parts of 1 N aqueous ammonia (equivalent to 2.0 carboxylic acid is 2.0) and After sufficiently stirring at 210 rpm, 133 parts of deionized water was added and further stirred to adjust the temperature to 25 ° C. Subsequently, 133 parts of deionized water was added dropwise under the same conditions to prepare a fine particle dispersion by phase inversion emulsification. The peripheral speed of the stirring blade at this time was 0.71 m / s. Next, 255 parts of deionized water was added (the amount of deionized water such that the total amount of 1N ammonia water and water was 593 parts) to adjust the amount of solvent.

Subsequently, 1.4 parts of Emar 0 (manufactured by Kao Corporation) which is an anionic emulsifier was diluted with 30 parts of water and added. Thereafter, the temperature is adjusted to 25 ° C. and the rotational speed is adjusted to 158 rpm, and an aqueous solution of 3.5% ammonium sulfate is dropped until the particle diameter grows to 5.5 μm. Thereafter, the particle diameter is adjusted to 7 μm under the same conditions. Stirring was continued until growth and the coalescence operation was completed. At this time, the amount of ammonium sulfate added was 200 parts. The peripheral speed of the stirring blade was 0.54 m / s. Next, solvent removal was performed using an evaporator. Next, the obtained dispersed particles were washed. In this process, a Kiriyama funnel (Kiriyama filter paper No. 5A set) with Kiriyama filter paper (No. 3) placed on the suction bottle is set. The dispersed particles were placed on the funnel, and the air in the suction bottle was drawn with a vacuum pump. Thereafter, the particles on the filter paper were taken out, placed in an aluminum case, and dried by freeze-drying to obtain toner base D.
Next, the external addition process was performed as follows.
-"Toner base D" 100 parts by mass-Silica HDK3050EP (Wacker Chemicals Co., Ltd.) 1 part by mass was mixed with a Henschel mixer, and then toner D was obtained through a sieve.

(Toner Production Example 5)
545 parts of mill base MB2 was charged into a cylindrical 2 L separable flask having a Max blend blade as a stirring blade, and then 39.4 parts of 1N aqueous ammonia (equivalent to 1.1 carboxylic acid was 1.1). After sufficiently stirring at 210 rpm, 133 parts of deionized water was added and further stirred to adjust the temperature to 25 ° C. Subsequently, 133 parts of deionized water was added dropwise under the same conditions to prepare a fine particle dispersion by phase inversion emulsification. The peripheral speed of the stirring blade at this time was 0.71 m / s. Next, 288 parts of deionized water was added (the amount of deionized water such that the total amount of 1N ammonia water and water was 593 parts) to adjust the amount of solvent.

Subsequently, 1.4 parts of Emar 0 (manufactured by Kao Corporation) which is an anionic emulsifier was diluted with 30 parts of water and added. Thereafter, the temperature is adjusted to 25 ° C. and the rotational speed is adjusted to 158 rpm, and an aqueous solution of 3.5% ammonium sulfate is dropped until the particle diameter grows to 5.5 μm. Thereafter, the particle diameter is adjusted to 7 μm under the same conditions. Stirring was continued until growth and the coalescence operation was completed. The amount of ammonium sulfate added at this time was 150 parts. The peripheral speed of the stirring blade was 0.54 m / s. Next, solvent removal was performed using an evaporator. Next, the obtained dispersed particles were washed. In this process, a Kiriyama funnel (Kiriyama filter paper No. 5A set) with Kiriyama filter paper (No. 3) placed on the suction bottle is set. The dispersed particles were placed on the funnel, and the air in the suction bottle was drawn with a vacuum pump. Thereafter, the particles on the filter paper were taken out, put in an aluminum case, and dried by freeze-drying to obtain toner base E.
Next, the external addition process was performed as follows.
-"Toner base E" 100 parts by mass Silica HDK H2000 (Wacker Chemicals Co., Ltd.) 1 part by mass was mixed with a Henschel mixer, and then Toner E was obtained through a sieve.

<Evaluation method>
The obtained toner was measured for particle size distribution by Coulter Counter Multisizer TAII.

The conditions when measuring with the above apparatus are as follows.
(1) Preparation of toner particle suspension 0.1 g of a surfactant (ELCLEAR (manufactured by Chugai Photo Chemical Co., Ltd.)) is added to 20 g of water, and 0.04 g of toner as a sample is further added. The toner particles are suspended in water using an ultrasonic disperser.
(2) Measurement conditions Measurement temperature: 25 ° C
Measuring humidity: 60%
Number of measured toner particles: 5000 ± 2000

Table 4 shows the granulation conditions and evaluation results of Toner Production Example 5 and Toner Production Example 6.

<Examples and Comparative Examples>
Example 1
Put 1kg of magnetite carrier core (85μm) into a 10L Henschel mixer (Mitsui Mine) with ST / A ₀ blade set, and set the deflector so that the tip of the deflector blade is 5mm from the wall of the Henschel wall. Water was passed through the Henschel wall surface, mixing was performed at 3000 rpm for 60 minutes, and sieved with a sieve having an opening of 38 μm to obtain carrier A active substance. The carrier A was coated with a silicone resin by a spray drying method to obtain a carrier A.

(Example 2)
Carrier B was obtained in the same manner as in Example 1 except that the treatment time in the Henschel mixer in Example 1 was 90 minutes.

(Example 3)
Carrier C was obtained by the same method as in Example 1 except that the carrier core in Example 1 was a ferrite carrier core (85 μm).

(Comparative Example 1)
A carrier D was obtained in the same manner as in Example 1 except that the treatment with a Henschel mixer was not performed in Example 1.

(Comparative Example 2)
Carrier E was obtained in the same manner as in Example 2 except that the treatment with a Henschel mixer was not performed in Example 2.

<Adjustment of developer>
The developer was prepared by mixing and stirring 5 parts by mass of toner A and 95 parts by mass of carrier A.

  Similarly, developers shown in Tables 6 to 10 were prepared using toner A to toner E and carrier A to carrier E.

(Print test)
(1) Evaluation of positively charged toner Using a commercially available laser beam printer A (with a selenium photoreceptor), the print quality by continuous printing was evaluated, and the charge amount of the developer was measured. The charge amount was measured with a blow-off charge amount measuring machine. The fog was obtained by using a Macbeth densitometer RD-918 and subtracting the density of the white paper before printing from the density of the white background. In addition, Betamura is judged visually.
(2) Evaluation of negatively charged toner Using a commercially available laser beam printer A (OPC photoreceptor mounted), the print quality by continuous printing was evaluated, and the charge amount of the developer was measured. The charge amount was measured with a blow-off charge amount measuring machine. The fog was obtained by using a Macbeth densitometer RD-918 and subtracting the density of the white paper before printing from the density of the white background. In addition, Betamura is judged visually.

  The above evaluation results are shown in Tables 6 to 10.

＊上記表６〜表１０において、
「カブリ評価」○：0.01未満、△：0.01〜0.03未満,×：0.03以上
「印刷枚数」１ｐ：１枚目、５ｋｐ：５０００枚目、１０ｋｐ：１００００枚目

* In Table 6 to Table 10 above,
“Fog evaluation” ○: Less than 0.01, Δ: Less than 0.01 to 0.03, x: 0.03 or more “Number of printed sheets” 1p: 1st sheet, 5kp: 5000th sheet, 10kp: 10,000th sheet

Claims (6)

The average shape factor SF-1 obtained using the image processing analyzer is:
1.00 ≦ average shape factor SF-1 ≦ 1.35
And the value of the 10% shape factor SF-1 is
10% SF-1 ≦ 1.60
A carrier for an electrostatic charge image developer. The value of the 10% shape factor SF-1 is
10% SF-1 ≦ 1.55
The carrier for an electrostatic charge image developer according to claim 1. The value of the 10% shape factor SF-1 is
10% SF-1 ≦ 1.45
The carrier for an electrostatic charge image developer according to claim 1. The value of the average shape factor SF-1 is
1.00 ≦ average shape factor SF-1 ≦ 1.30
The carrier for an electrostatic charge image developer according to any one of claims 1, 2, and 3. The carrier for an electrostatic charge image developer according to claim 1, wherein the electrostatic charge image developer carrier is a magnetite carrier. An electrostatic charge image developer comprising the carrier for electrostatic charge image developer according to claim 1, and a toner.