Classifications

• • G—PHYSICS
  • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
  • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
  • G03G9/00—Developers
  • G03G9/08—Developers with toner particles
  • G03G9/093—Encapsulated toner particles
• • G—PHYSICS
  • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
  • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
  • G03G9/00—Developers
  • G03G9/08—Developers with toner particles
  • G03G9/087—Binders for toner particles
  • G03G9/08775—Natural macromolecular compounds or derivatives thereof
  • G03G9/08782—Waxes
• • G—PHYSICS
  • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
  • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
  • G03G9/00—Developers
  • G03G9/08—Developers with toner particles
  • G03G9/093—Encapsulated toner particles
  • G03G9/09307—Encapsulated toner particles specified by the shell material
  • G03G9/09314—Macromolecular compounds
• • G—PHYSICS
  • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
  • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
  • G03G9/00—Developers
  • G03G9/08—Developers with toner particles
  • G03G9/093—Encapsulated toner particles
  • G03G9/0935—Encapsulated toner particles specified by the core material
  • G03G9/09357—Macromolecular compounds
  • G03G9/09371—Macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
• • G—PHYSICS
  • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
  • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
  • G03G9/00—Developers
  • G03G9/08—Developers with toner particles
  • G03G9/097—Plasticisers; Charge controlling agents
  • G03G9/09733—Organic compounds

Definitions

• the present invention relates to a polymerized toner and a method for producing the same, and more particularly, to a polymerized toner for developing an electrostatic latent image formed by an electrophotographic method, an electrostatic recording method or the like, and a method for producing the same. Further, the present invention relates to an image forming method using the polymerized toner and an image forming apparatus provided with the polymerized toner.
• a developer for visualizing an electrostatic latent image includes a two-component developer composed of a toner and carrier particles, and substantially only a toner. There is a one-component developer that does not use rear particles.
• the one-component developer includes a magnetic one-component developer containing magnetic powder and a non-magnetic one-component developer containing no magnetic powder.
• a fluidizing agent such as colloidal silica is often added independently in order to increase the fluidity of the toner.
• colored particles obtained by dispersing a coloring agent such as a black rubber and other additives in a binder resin and granulating the toner are used.
• Toner production methods are roughly classified into a pulverization method and a polymerization method.
• a synthetic resin, a colorant and, if necessary, other additives are melt-mixed, pulverized, and then classified to obtain particles having a desired particle size, thereby obtaining a toner.
• various additives such as a coloring agent, a polymerization initiator, and, if necessary, a crosslinking agent and a charge controlling agent are added to the polymerizable monomer.
• a polymerizable monomer composition in which the additive is not uniformly dissolved or dispersed is prepared, and then dispersed in an aqueous dispersion medium containing a dispersion stabilizer using a stirrer to obtain a polymerizable monomer composition.
• the toner (polymerized toner) having a desired particle size is obtained by forming fine droplet particles of the product, and then raising the temperature to carry out suspension polymerization.
• an electrostatic latent image is substantially formed by toner.
• an image forming apparatus such as an electrophotographic apparatus and an electrostatic recording apparatus
• an image is formed on a uniformly charged photoconductor by forming an electrostatic latent image, and toner is attached to the electrostatic latent image.
• the toner image is transferred to a transfer material such as transfer paper, and then the unfixed toner image is formed by various methods such as heating, pressing, and solvent vapor.
• Fixed on the transfer material In the fixing process, in many cases, a transfer material on which a toner image has been transferred is passed between a heating roll (fixing roll) and a pressure roll, and the toner is heated and pressed to fuse it onto the transfer material. .
• An image formed by an image forming apparatus such as an electrophotographic copying machine is required to have higher definition year by year.
• toner obtained by a pulverization method has been the mainstream toner used in image forming apparatuses.
• the pulverization method colored particles having a wide particle size distribution are easily formed. Therefore, in order to obtain satisfactory developing characteristics, it is necessary to classify the pulverized product to adjust the particle size distribution to a somewhat narrower range.
• the classification itself is complicated and the yield is low, and the toner yield is greatly reduced. Therefore, in recent years, polymerized toners that can easily control the particle size and do not need to go through complicated manufacturing processes such as classification have been attracting attention.
• a polymerized toner having a desired particle size and particle size distribution can be obtained without performing pulverization or classification.
• conventional polymerized toners have been used in recent years to speed up copying, to achieve full color, and to save energy. There was a problem that it was not possible to adequately respond to demands such as gearing.
• the heating roll temperature can be reduced, but if the heating roll temperature is not so lowered, the fixing time can be reduced. It can also cope with copying and high speed.
• toner In the design of toner, in order to meet the demands of image forming apparatuses such as energy saving and high-speed copying, it is only necessary to lower the glass transition temperature of the binder resin constituting the toner. However, if the toner is composed of a binder resin having a low glass transition temperature, the toners will block each other during storage, transportation, or during the toner box operation of the image forming apparatus. Agglomerates tend to be formed, and so-called poor storage stability.
• melt viscosity near the fixing temperature of the toner it is necessary to design the melt viscosity near the fixing temperature of the toner to be lower than that of the conventional one.
• Techniques for lowering the melt viscosity of the toner include lowering the molecular weight of the binder resin and lowering the glass transition temperature compared to conventional binder resins for toner.
• the toner causes blocking, resulting in toner having poor storage stability.
• Japanese Patent Application Laid-Open Publication No. Hei 3-136605 discloses a polymerizable monomer containing a colorant and a charge control agent.
• a method of suspension polymerization in the presence of a mouth monomer has been proposed.
• Macromonomer is a relatively long linear molecule having a polymerizable functional group at an end of a molecular chain, for example, an unsaturated group such as a carbon-carbon double bond.
• the macromonomer is incorporated as a monomer unit into the molecular chain of the produced polymer, a large number of macromonomer due to long linear molecules of the macromonomer are included in the molecular chain. Branching occurs.
• the resulting polymer apparently becomes a high molecular weight polymer due to the entanglement of its branches, so-called physical crosslinking, so that the offset resistance of the polymerized toner is improved.
• the physical cross-linking by the macromonomer component is a loose cross-linking structure, unlike the chemical cross-linking using a cross-linkable monomer such as divinylbenzene, so that the cross-linking structure is reduced by heating. Easy to slip No. Therefore, this polymerized toner is easily melted during fixing using a heating roll, and has excellent fixability. However, in the case of this polymerized toner, aggregation of toners easily occurs during storage, and the storage stability is not satisfactory.
• the conventional methods for lowering the fixing temperature of the toner and improving the uniform melting property improve the fixing property of the obtained toner, but decrease the storage stability. Will occur.
• a toner composed of a binder resin having a low glass transition temperature is coated with a polymer having a high glass transition temperature to improve the blocking resistance.
• So-called capsule-type toners that solve the problem of storage stability have been proposed.
• Japanese Patent Application Laid-Open No. 60-173552 discloses a method in which the surface of a spherical core particle having a fine particle diameter is formed using a jet mill device.
• a method for forming a coating layer comprising a coloring agent, magnetic particles, or a conductive agent and a binder resin has been proposed.
• the core particles transparent thermoplastic resin such as acrylate resin / styrene resin is used.
• This publication reports that this method can provide a multi-layer toner having excellent fluidity and improved functionality.
• nucleus particles having a low glass transition temperature are used, the nucleus particles themselves agglomerate.
• the thickness of the binder resin to be attached to the core particles tends to be large. Therefore, in this method, it is difficult to obtain a toner having improved fixability and uniform melting property while maintaining storability.
• Japanese Unexamined Patent Publication (Kokai) No. 2-2595967 discloses a cross-linking prepared by suspension polymerization in a solution in which a polymer for encapsulation, a charge controlling agent and a release agent are dissolved in an organic solvent. After adding the toner particles, add a poor solvent to Bridge A method for producing an electrophotographic toner has been proposed in which a coating of a polymer for encapsulation containing a charge control agent and a release agent is formed on the surface of toner particles.
• the solubility of the encapsulating polymer is reduced by dropping the poor solvent and the polymer is precipitated on the surface of the crosslinked toner particles, it is difficult to obtain spherical particles. According to this method, the capsule wall formed on the surface of the crosslinked toner particles is not uniform in thickness and relatively thick. As a result, the effect of improving the developing property and the fixing property is not sufficient.
• Japanese Patent Application Laid-Open No. 57-45558 discloses that a core particle formed by polymerization is mixed and dispersed in an aqueous solution of 1 to 40% by weight of a latex, and then a water-soluble inorganic
• a method for producing a toner for developing an electrostatic image in which a salt is added to form a coating layer of fine particles obtained by emulsion polymerization on the surface of nucleus particles.
• the toner has a large environmental dependence on the charging characteristics due to the effect of the surfactant and the inorganic salt remaining on the fine particles.
• the charging is reduced under high temperature and high humidity conditions. There was a drawback
• Japanese Patent Application Laid-Open No. 61-118578 discloses a suspension particle of a composition containing a vinyl monomer, a polymerization initiator and a colorant to obtain core particles.
• a vinyl monomer which gives a polymer having hydrophilicity equal to or higher than that of the resin contained in the core particles and having a glass transition temperature higher than the glass transition temperature of the resin
• a method for producing a toner in which a body is polymerized to form a shell.
• the gazette discloses that in order to prevent a part of the melted toner from adhering to the surface of the fixing roll, core particles are separated from low molecular weight polyethylene, carnauba wax, silicone oil and the like.
• a mold agent may be added.
• a vinyl monomer for forming a shell on the core particles is adsorbed. Since the vinyl monomer is grown, it is often difficult for the vinyl monomer absorbed into the core particles to polymerize to form a clear core-shell structure. Therefore, it is difficult to obtain a toner having sufficiently improved storability by this method.
• the thickness of the shell had to be increased in order to clarify the core's seal structure and improve the storage stability.
• Japanese Patent Application Laid-Open No. 7-128908 discloses that a monomer composition containing a polymerizable monomer, a colorant, and a release agent is directly subjected to suspension polymerization in an aqueous medium.
• the release agent is contained in an amount of 10 to 40 parts by weight based on 100 parts by weight of the polymerizable monomer, and the release agent on the toner surface is removed after the polymerization step.
• a method for producing a toner including a process is disclosed. In this method, when a polymer having a polar group is added to a monomer and polymerized, the polar polymer is collected in the particle surface layer, and thus a core-shell structure is formed.
• Another object of the present invention is to provide a polymerized toner capable of coping with high-speed copying and printing, full colorization, and energy saving, and a method for producing the same. To provide.
• an object of the present invention is to provide a polymerized toner capable of forming a toner image exhibiting excellent transparency (OHP transparency) when printed on a 0-HP sheet and fixed. It is to provide a manufacturing method.
• Another object of the present invention is to provide an image forming method using a polymerized toner having such excellent various properties, and an image forming apparatus containing the toner.
• the present inventors have conducted intensive studies to overcome the problems of the prior art, and as a result, have found that a polyfunctional ester compound formed from a polyhydric alcohol having three or more functional groups and a carboxylic acid, and a coloring agent containing a coloring agent.
• Core-shell structure in which core particles made of coalesced particles are covered with a seal made of a polymer having a glass transition temperature higher than the glass transition temperature of the polymer component constituting the core particles Of polymerized toner.
• the polymerized toner preferably comprises a composition containing a polyfunctional ester compound, a colorant, and a polymerizable monomer capable of forming a polymer having a glass transition temperature of 80 ° C. or lower, preferably a macromolecule.
• Suspension polymerization is performed in the presence of a monomer to prepare colored polymer particles.Then, the colored polymer particles are used as core particles, and a polymer constituting the core particles is formed in the presence of the core particles.
• a polymerizable monomer capable of forming a polymer having a higher glass transition temperature than the component by suspension polymerization to form a shell comprising a polymer layer covering the core particles. It can be suitably manufactured.
• the fixing temperature can be lowered by the core particles containing the polyfunctional ester compound and the polymer component having a low glass transition temperature, the uniform melting property is improved, and the copy and copy operations are improved. It can meet the demands of high-speed printing, full-strength printing, and 0 HP transparency.Furthermore, high-quality images can be produced without fogging or print density reduction. Formation can do.
• the polymerized toner of the present invention can exhibit good storage stability (blocking resistance) because the core particles can be covered with a thin shell, and have good fixability and uniform melting property. Can respond to various demands.
• the present invention has been completed based on these findings.
• a core particle composed of a polyfunctional ester compound formed from a polyhydric alcohol having three or more functional groups and carboxylic acid and a colored polymer particle containing a coloring agent is provided.
• a polyfunctional ester compound formed from a polyhydric alcohol having three or more functional groups and a carboxylic acid, a colorant, and a glass transition temperature in an aqueous dispersion medium containing a dispersant A polymerizable monomer composition containing a polymerizable monomer for a core capable of forming a polymer at 80 ° C. or lower is subjected to suspension polymerization to prepare core particles composed of colored polymer particles.
• a polymerizable monomer for a seal capable of forming a polymer having a glass transition temperature higher than the glass transition temperature of the polymer component constituting the core particles.
• the present invention provides a method for producing a polymer toner having a core-shell structure in which a monomer is suspension-polymerized to form a seal comprising a polymer layer covering core particles.
• an image forming method including a step of attaching a toner to a surface of a photoreceptor on which an electrostatic latent image is formed to form a visible image, and then transferring the visible image to a transfer material.
• an image forming method characterized by using the above-mentioned core-to-serial type polymerized toner as the toner. Is done.
• a photoreceptor a unit for charging the surface of the photoreceptor, a unit for forming an electrostatic latent image on the surface of the photoreceptor, a unit for containing toner, and an electrostatic latent image on the photoreceptor surface by supplying the toner
• an image forming apparatus including a unit for developing an image to form a toner image, and a unit for transferring the toner image from the surface of the photoreceptor to a transfer material
• the unit for accommodating the toner is the core-shell type.
• An image forming apparatus characterized by containing a polymerized toner having a structure.
• FIG. 1 is a sectional view showing an example of an image forming apparatus to which the polymerized toner of the present invention is applied.
• the polymer toner of the present invention is a polymer toner having a core-shell structure comprising core particles and a shell covering the core particles.
• the polymerized toner of the present invention can be obtained by polymerizing a polymerizable monomer for sealing in the presence of core particles.
• the core particle contains, as essential components, a polymer component (binder resin), a polyfunctional ester compound formed from a polyhydric alcohol having three or more functional groups and a carboxylic acid, and a coloring agent. It is.
• the glass transition temperature of the polymer component constituting the shell X is higher than the glass transition temperature of the polymer component constituting the core particle.
• the polyfunctional ester compound used in the present invention is an ester formed from a polyhydric alcohol having three or more functional groups, a carboxylic acid, and a carboxylic acid.
• trifunctional or higher-functional alcohols examples include glycerin and ⁇ Aliphatic alcohols, such as aliphatic alcohols, pentaglycerol, etc .; cycloaliphatic alcohols, such as fluorognositol, quenolitol, inositol, etc .; Tris (Hydroxymethyl) Aromatic alcohol such as benzene; D—Elithrose, L—Arabinose, D—Mannose, D—Galactose, D — Sugars such as fructose, L-rhamnose, saccharose, maltose, lactose; Elitritol, D—trait, L—a Sugar alcohols such as rabbits, insomniaits, and xylit; and the like. Of these, the Pencil Elistillery is preferred.
• carboxylic acid examples include acetic acid, butyric acid, cabronic acid, phenanthic acid, hydracrylic acid, pelargonic acid, hydrpuric acid, undecanoic acid, and lactic acid.
• Aliphatic carboxylic acids such as, linoleic acid, linolenic acid, behenylic acid, tetratolic acid, xymenic acid; cyclohexan carboxylic acid, hexahydroy Alicyclic carboxylic acids such as sophthalic acid, hexahydroterephthalic acid, 3,4,5,6—tetrahydrophthalic acid; benzoic acid, toluic acid, cumic acid, Phthalic acid, isophthalic acid, terephthalic acid, trimesic acid, trimellitic acid, hem
• the polyfunctional ester compound used in the present invention reacts with three or more functional groups (OH groups) of the polyhydric alcohol to form ester bonds, respectively.
• the carboxylic acids formed may be the same or different. If the type of carboxylic acid that reacts with the polyhydric alcohol is different, the difference between the maximum and minimum number of carbon atoms between the sulfonic acids is preferably 9 or less, more preferably 9 or less. It is desirable to set it to 5 or less.
• the polyfunctional ester compound is represented by the formula (I)
• R 4 COOCH 2 (where R 1 R 2 , R J , and R 4 are each independently an alkyl group or a phenyl group, and the number of carbon atoms of the alkyl group or the phenyl group is It is preferably from 10 to 30, more preferably from 13 to 25.)
• the compound represented by the formula (1) is preferred.
• polyfunctional ester compound examples include pentaerythritol tetrastearate [in the formula (I), all of R 1 R 2 , R d , and R 4 are CH 3 ( CH 9 ) a compound having 16 groups], pentaerythritol tetraamilystate (in the formula (I), R 1 R ⁇ R "and R 4 are each CH 3 (CH 9 ) 19 Group compound], glycerol tri-arachinic acid, etc.
• the polyfunctional ester compound is preferably a compound which easily dissolves in the polymerizable monomer for the core.
• the polyfunctional ester compound is usually used in an amount of 0.1 part by weight based on 100 parts by weight of the polymer component constituting the core particles or the monomer (polymerizable monomer for core) forming the polymer component. It is used in a proportion of up to 40 parts by weight, preferably 1 to 20 parts by weight, more preferably 3 to 15 parts by weight.
• the proportion of the polyfunctional ester compound used is within the above range, it has a low fixing temperature and a uniform melting property, and is excellent in storage stability (blocking resistance). In addition, it is possible to obtain a superposed toner which is less likely to cause fogging and lowering of print density. If the proportion of the polyfunctional ester compound is too small, the effect is small, and if it is too large, it is difficult to form core particles and the storage stability is reduced.
• coloring agent used in the present invention examples include bonbon black, titanium white, nig mouth thin base, aniline bulldog, chalk oil blue, kuromi ero, unoretrama Dyes and pigments, such as Limbnore, Orientoinoledo, Phthalocyanine, Malachite Greenoxaleate; Cobalt, Nickel, Iron Oxide, Iron Oxide, Iron Oxide Magnetic particles such as manganese, zinc oxide, and nickel oxide; and the like.
• Basic Red 1 C. I. Modular Red 30 C.
• Direct Blue I C. I. Direct Blue I. 2, C. I. Ash C.I.D.B.1 9 C.I.A.D.B.I.15, C.I.B.I.C.B.I.3, C.I.B.I.C.B.I.5 5 C.I. C.I. direct green 6 C.I. basic green 4, C.I. basic green 6, and the like.
• Pigments for magnetic color toners include graphite, cadmium yellow, mineral first yellow, neba erotic, neftoi erotic S, hanzai erotic G—man toy erotic NCG, Tarazine lake, red-mouthed graphite, molybdenum orange,.
• CI pigment pigments 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 and 1 2 are magenta coloring pigments for full color toners. , 13, 14, 15, 16, 17, 18, 19, 21, 22, 23, 30, 31, 32, 37, 38, 39, 4 0, 41, 48, 49, 50, 51, 52, 53, 54, 55, 57, 58, 60, 63, 64, 68, 81, 8 3, 8 7, 8 8, 89, 90, 1 1 2, 1 1 4, 1 2 2, 1 2 3, 1 63, 202, 206, 207, and 20 9; C. I. Pigmented Nozzle 1 9; C. I. Notting Red 1, 2, 10, 10, 13, 15, 23, 29, and 3 5; and the like.
• magenta dyes for full color toner examples include C.I.Survent Red 1,3,8,23,24,25,27,30,49,81, 82, 83, 84, 100, 109, and 121; C.I.D.S., 0 — Thread 9; C.I.S. Oil soluble dyes, such as C.I. disperse violet 1; C.I. base red 1,2,3,14,21,27; 9, 1 2, 1 3, 1, 4, 15, 15, 17, 18, 22, 2, 23, 24, 27, 29, 32, 34, 35, 36, 37, 38, 39, and 40; C.I.Basic Violet 1, 3, 7, 10, 14, 14, 15, 21, 21, 25, 26, 27, and Basic dyes such as 28;
• the cyan pigments for full color toners include C.I. U-blue 2 3 15 16 and 17; C.I. U-blue 6; C.I. Acid blue 45; and 15 phthalanomidometyl groups substituted on the phthalocyanine skeleton Copper phthalocyanine pigment; and the like.
• These dyes and pigments are usually used in an amount of 0.120 parts by weight, preferably 110 parts by weight, based on 100 parts by weight of the polymer component constituting the core particles or the polymerizable monomer for the core. Used in parts by weight.
• the magnetic particles are usually used in an amount of 110 parts by weight, preferably 550 parts by weight, based on 100 parts by weight of the polymer component or the core polymerizable monomer constituting the core particles. Used.
• the core particles used in the present invention include, as a polymer component (binder resin), a vinyl monomer such as a polyester resin or a (meth) acrylic acid ester-styrene copolymer. (Co) It contains a polymer and the like.
• a (meth) acrylic acid ester-styrene copolymer is preferred because it is easy to form particles by polymerization and to control the glass transition temperature. .
• the volume average particle diameter (dv) of the core particles is usually 0.520 ⁇ m, preferably:! 110 0m. If the core particles are too large, the image resolution will decrease.
• the volume average particle size (dv) and the Z number average particle size (dp) are usually 1.7 or less, preferably 1.5 or less. If this ratio is too large, the image solution It shows a tendency that image resolution decreases.
• the core particles used in the present invention are not particularly limited by the production method, and may be any of emulsion polymerization, suspension polymerization, precipitation polymerization, and soap-free polymerization.
• the polymerization method is suitable for uniformly containing the polyfunctional ester compound and the colorant in the formed core particles and improving the fixability.
• the polymerizable monomer for a core used in the present invention has a glass transition temperature of usually 80 ° C or lower, preferably 10 to 70 ° C, more preferably 15 to 60 ° C. It can form a polymer of C.
• the polymerizable monomers for the core can be used alone or in combination of two or more. If the glass transition temperature of the polymer composed of the polymerizable monomer for the core is too high, the fixing temperature will be high, and the OHP permeability will be reduced, making it unsuitable for high-speed copying and printing.
• the glass transition temperature (T g) of a polymer is a calculated value (referred to as calculated T g) calculated according to the type of monomer used and the proportion used.
• Tg of a homopolymer formed from the monomer is defined as the Tg of the polymer in the present invention.
• T g of Po Li styrene les down is 1 0 0 ° C Der Luca et al.
• the monomer is 1 Ding ⁇ 0 o ° c To form a polymer.
• the Tg of the copolymer is calculated according to the type of the monomer used and the proportion used. For example, when 78% by weight of styrene and 22% by weight of n-butyl acrylate are used as monomers, the styrene-n-butyl acrylate formed at this monomer ratio is used. Since the Tg of the acrylate copolymer is 50 ° C, this monomer is said to form a polymer having a Tg of 50 ° C. In addition, the definition of “polymerizable monomer for core capable of forming a polymer having a glass transition temperature of 80 ° C.
• each of the monomers forms a polymer having a T g of 80 ° C. or less. It does not mean that you must do it.
• the homopolymer formed from the monomer must have a Tg of 80 ° C or lower.
• the Tg of the copolymer formed from the mixture of the monomers should be 80 ° C or less.
• the mixture of the monomers may contain a single polymer having a Tg of more than 80 ° C.
• the homopolymer of styrene has a Tg of 100 ° C, but is mixed with a monomer that forms a low Tg polymer (for example, n-butyl acrylate).
• a monomer that forms a low Tg polymer for example, n-butyl acrylate
• styrene is used as a kind of the core polymerizable monomer. It can be.
• a vinyl monomer is usually used as the polymerizable monomer for the core. By using each vinyl monomer alone or in combination of two or more, the Tg of the polymer is adjusted to a desired range.
• vinyl monomer used in the present invention examples include styrene monomers such as styrene, vinyl tolylene, and methyl styrene; acrylic acid; Crylic acid: Methynoacrylate, Ethyl acrylate, Propyl polyacrylate, Butyl acrylate, 2-Acetyl hexyl, Acrylate Dimethylaminoethyl oleate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, butyl methacrylate, methacrylate 2 — Methylhexyl, dimethylaminomethacrylate, acrylonitrile, acrylonitrile, methacrylonitrile, acrynoreamid, methacrylic Derivatives of acrylic acid or methacrylic acid, such as ruamide; Ethylenically unsaturated monoolefins such as styrene, propyl
• a combination of a styrene-based monomer and a derivative of (meth) acrylic acid is preferably used as the polymerizable monomer for the core.
• Particularly preferred examples are styrene and butyl acrylate (ie, n-butyl acrylate), styrene and 2-ethyl acrylate (ie, 2 —Ethylhexyl acrylate).
• crosslinkable monomers include aromatic divinyl compounds such as divinylbenzene, divinylnaphthalene, and derivatives thereof; ethylene glycol dimethacrylate, ethylene glycol dimethacrylate, and the like. And the like. Diethylenically unsaturated carboxylic acid esters such as acrylate; divinyl compounds such as N, N-divinylaniline and divinyl ether; compounds having three or more vinyl groups; You.
• crosslinkable monomers may be used alone or in combination of two or more. They can be used in combination.
• the crosslinkable monomer is used in an amount of usually 0.1 to 5 parts by weight, preferably 0.3 to 2 parts by weight, based on 100 parts by weight of the polymerizable monomer for the core. Is desirable.
• co-polymerization of a macromolecule with a polymerizable monomer for a core is preferable for improving the balance between the storage stability and the fixability of the polymerized toner.
• a polymerizable monomer composition containing a polyfunctional ester compound, a colorant, and a polymerizable monomer for a core is prepared in the presence of a macromonomer. It is only necessary to synthesize colored polymer particles (core particles) by polymerization. Practically, a method in which a macromonomer is contained in a polymerizable monomer composition and subjected to suspension polymerization is preferable.
• Macromonomers are relatively long linear molecules that have a polymerizable functional group at the end of the molecular chain (for example, an unsaturated group such as a carbon-carbon double bond). . Macromonomers are those having a vinyl polymerizable functional group at the end of the molecular chain, and usually have an average molecular weight of 1,000 to 300,000. Reamers are preferred. When a macromonomer having a small number average molecular weight is used, the surface portion of the polymerized toner tends to be soft and the storage stability tends to be reduced. The use of a macro-mouthed monomer having a large number average molecular weight results in poor flowability of the macro-mouthed monomer and lowers the fixability and the storage stability.
• Examples of the vinyl polymerizable functional group at the end of the macromolecule molecular chain include an acryloyl group and a methacryloyl group. Tacryloyl groups are preferred.
• the macromonomer used in the present invention preferably has a glass transition temperature higher than the glass transition temperature of the polymer obtained by polymerizing the polymerizable monomer for the core. Weight obtained by polymerizing polymerizable monomer for core
• the level of T g between the coalescence and the macromonomer is relative.
• the macromonomer is a polymer having a T g of more than 80 ° C. Good.
• the core monomer forms a polymer having a Tg of 50 ° C
• the macromonomer may have a Tg of 60 ° C, for example.
• the T g of a macromonomer is a value measured by a normal measuring instrument such as DSC.
• macromonomer used in the present invention examples include styrene, styrene derivatives, methacrylic acid esters, acrylic acid esters, ditrinol acrylate, Polymer obtained by polymerizing methacrylonitrile alone or two or more kinds thereof; Macromonomer having a polysiloxane skeleton; And the like disclosed on pages 4 to 7 of the above-mentioned publication.
• hydrophilic polymers in particular, polymers obtained by polymerizing methacrylic acid esters or acrylic acid esters alone or in combination thereof are described in the present invention. It is suitable for.
• the amount of the macromonomer is usually 0.01 to 10 parts by weight, preferably 0.03 to 5 parts by weight, based on 100 parts by weight of the polymerizable monomer for the core. More preferably, it is 0.05 to 1 part by weight. If the amount of macromonomer used is small, the preservability will decrease. As the amount of the macromonomer increases, the fixability decreases.
• the core particles are preferably obtained by suspension polymerization of a core polymerizable monomer, a macromonomer, and, if necessary, a crosslinkable monomer.
• the suspension polymerization is usually performed in an aqueous dispersion medium containing a dispersant.
• polymerizable monomer for core vinyl monomer
• polyfunctional S Ter compounds coloring agents, macromonomers, bridging monomers, radical polymerization initiators, and other additives selected as needed are mixed and uniformly dispersed with ball mill, etc.
• a mixed solution polymerizable monomer composition
• the mixed solution is poured into an aqueous dispersion medium containing a dispersant, and dispersed using a mixing device having a high shearing force. After granulation into fine droplets, suspension polymerization is usually performed at a temperature of 30 to 200 ° C.
• the dispersant suitably used in the present invention is a poorly water-soluble metal compound.
• poorly water-soluble metal compounds include sulfates such as barium sulfate and sulfuric acid norm; carbonates such as barium carbonate, calcium carbonate and magnesium carbonate; calcium phosphate Phosphates such as aluminum; metal oxides such as aluminum oxide and titanium oxide; metal hydroxides such as aluminum hydroxide, magnesium hydroxide, and ferric hydroxide And the like.
• colloids of poorly water-soluble metal hydroxides are preferred because the particle size distribution of the polymer particles can be narrowed and the sharpness of the image is improved.
• the colloid of the poorly water-soluble metal hydroxide is not limited by its production method, but the poorly water-soluble metal hydroxide can be obtained by adjusting the pH of the aqueous solution of the water-soluble polyvalent metal compound to 7 or more. Colloids of metal hydroxides, especially colloids of poorly water-soluble metal hydroxides formed by the reaction of a water-soluble polyvalent metal compound with an alkali metal hydroxide in the aqueous phase are preferred. New This colloid is used as an aqueous dispersion.
• the colloid of the poorly water-soluble metal compound used in the present invention has a number particle size distribution D 50 ( 50 % cumulative value of the number particle size distribution) of not more than 0.5 ⁇ m and (0% cumulative value) is preferably 1 or less.
• D 50 50 % cumulative value of the number particle size distribution
• the dispersant is used usually in an amount of 0.1 to 20 parts by weight based on 100 parts by weight of the comonomer. If the use ratio of the dispersant is too small, it is difficult to obtain sufficient polymerization stability, and a polymer aggregate is easily generated. Conversely, if the dispersing agent is used in an excessively large proportion, the effect of polymerization stability will be saturated, and it will not be economical. It is difficult to form.
• a water-soluble polymer can be used as a dispersant, if necessary.
• the water-soluble polymer include polyvinyl alcohol, methylcellulose, and gelatin.
• Radical polymerization initiators include persulfates such as potassium persulfate and ammonium persulfate; 4,4-azobis (4—cyanovaleric acid), 2,2—azobis (2 — Amidinopropane) dihydrochloride, 2, 2 — Azobis-1 2 — Methyl-1 N—1, 1 — Bis (hydroxysimetyl) 1 2 — Hydroxexetil propioamide, 2 , 2'-Azobis (2,4-dimethylmethorino), 2,2'-azobisisobutyronitrino, 1,1'-azobis (to 1-cyclone) Azo compounds such as xanthane carbonyl); water-soluble radical initiators such as methethylethyl benzoide; Acetoxide, acetyl peroxide, dicumyl peroxide, lauroylpoxide, benzoyl peroxide, t-butyl butoxy 1 2 —ethyl hexano
• oil-soluble radical initiators are preferred, with a 10-hour half-life temperature of 60 to 80 ° C, preferably 65 to 80 ° C.
• an oil-soluble radical initiator selected from organic peroxides having a molecular weight of 250 or less is particularly preferred.
• t-butyl vinyloxy-2-ethylhexanoate in particular, has a low odor during printing and has a low environmental damage due to volatile components such as odor. This is preferable.
• the amount of the polymerization initiator to be used is usually 0.001 to 3% by weight based on the aqueous medium. If the amount of the polymerization initiator used is less than 0.001% by weight, the polymerization rate is low. If the amount is more than 3% by weight, particles having a particle diameter of less than 1 m are undesirably produced.
• various additives such as a molecular weight adjusting agent can be used in combination with the polymerizable monomer for core.
• the molecular weight regulator examples include menolenic butanes such as t-dodecylmercaptan, n-dodecylmenolecaptan, n-octylmenolecaptan; carbon tetrachloride, carbon tetrabromide and the like. Hachogenized hydrocarbons; and the like.
• the molecular weight adjusting agent can be added before the start of the polymerization or during the polymerization.
• the molecular weight modifier is used in an amount of usually 0.01 to 10 parts by weight, preferably 0.1 to 5 parts by weight, based on 100 parts by weight of the polymerizable monomer for the core. .
• the polyfunctional ester compound since the polyfunctional ester compound also functions as a release agent, it is not always necessary to use another release agent, but within a range that does not impair the object of the present invention.
• low molecular weight polyolefins such as low molecular weight polyethylene, low molecular weight polypropylene, low molecular weight polybutylene; paraffin waxes; etc.
• a release agent may be used.
• Lubricants such as oleic acid and stearic acid; dispersing aids such as silane-based or titanium-based cutting agents; and the like, for the purpose of uniformly dispersing the colorant in the core particles. May be used. Such lubricants and dispersants are usually used in a proportion of about 1/1000 to 1Z1, based on the weight of the colorant.
• the polymerization conversion is usually at least 80%, preferably at least 85%, more preferably at least 90%. If the polymerization conversion rate is less than 80%, a large amount of unreacted core polymerizable monomer remains, so even if the shell polymerizable monomer is added and polymerized. Since the copolymer of the polymerizable monomer for the core and the polymerizable monomer for the core covers the surface of the core particle, the Tg difference between the core particle and the sealant is small. As a result, the storage stability of the polymerized toner tends to decrease.
• the polymerized toner can be obtained by polymerizing a polymerizable monomer for sealing in the presence of core particles.
• the polymerizable monomer for a seal used in the present invention can form a polymer having a glass transition temperature higher than the glass transition temperature of the polymer component constituting the core particles.
• the Tg of the polymer obtained from the polymerizable monomer for sealing and the Tg of the polymer component constituting the core particles are relative to each other.
• the polymerizable monomer for the shell for example, monomers that form a polymer having a glass transition temperature of more than 80 ° C, such as styrene and methyl methacrylate, may be used alone. Or a combination of two or more. If the glass transition temperature of the polymer component of the core particles is much lower than 80 ° C, the polymerizable monomer for sealing will be 80 ° C or lower. The following polymer may be formed. It is necessary to set the glass transition temperature of the polymer comprising the polymerizable monomer for the shell to be at least higher than the glass transition temperature of the polymer component of the core particles.
• the glass transition temperature of the polymer obtained from the polymerizable monomer for shell is usually 50 to 120 ° C, preferably 60 to 200 ° C, in order to improve the storage stability of the polymerized toner. It is ⁇ 115 ° C, more preferably 80 ⁇ 110 ° C. If the glass transition temperature of the polymer composed of the polymerizable monomer for the shell is too low, even if the glass transition temperature is higher than the glass transition temperature of the polymer component of the core particles, the storage stability of the polymerized toner May decrease.
• the glass transition temperature of the polymer component of the core particles can be expressed by the calculated Tg of the polymer formed from the polymerizable monomer for the core in many cases.
• the difference in glass transition temperature between the polymer composed of the polymerizable monomer for core and the polymer composed of the polymerizable monomer for shell is usually 10 ° C. or more, preferably 10 ° C. or more. It is at least 20 ° C, more preferably at least 30 ° C.
• the polymerizable monomer be formed into droplets smaller than the number average particle diameter of the core particles in the aqueous dispersion medium. As the particle size of the droplets of the polymerizable monomer for the shell increases, the storage stability of the polymerized toner tends to decrease.
• a mixture of the polymerizable monomer for shell and an aqueous dispersion medium is finely dispersed using, for example, an ultrasonic emulsifier. I do.
• the aqueous dispersion thus obtained is preferably added to the reaction system in which the core particles are present.
• the polymerizable monomer for shell is not particularly limited by the solubility in water at 20 ° C, but the monomer having high solubility in water, specifically, the solubility in water at 20 ° C is 0.1. % By weight or more of the monomer
• the toner easily transfers to the surface, so that it is easy to obtain a polymerized toner having good storability.
• the migration to the surface of the core particles is slowed down. It is preferable to polymerize the monomer by forming it into fine droplets and then adding it to the reaction system. Even when a monomer having a solubility in water at 20 ° C of less than 0.1% by weight is used, an organic solvent having a solubility in water at 20 ° C of 5% by weight or more is added to the reaction system. As a result, the polymerizable monomer for sealing quickly moves to the surface of the core particles, and it becomes easier to obtain polymer particles having good storage properties.
• Polymerizable monomers for shells having a solubility in water at 20 ° C of less than 0.1% by weight include styrene, butynoleacrylate, 2-ethylhexyl acrylate, Examples include ethylene and propylene.
• (meth) acrylates such as methyl methacrylate and methyl acrylate
• Amino acids such as acrylic acid and methacrylonitrile; methacrylonitrile; acrylonitrile and methacrylonitrile vinyl Compounds; Nitrogen-containing vinyl compounds such as 4-vinylpyridine; vinyl acetate, acrolein and the like.
• Organic solvents that are preferably used when a sealing monomer having a solubility in water at 20 ° C of less than 0.1% by weight are methanol, ethanol, and the like.
• the organic solvent is added at a ratio such that the solubility of the polymerizable monomer for cinyl in the dispersion medium (total amount of water and the organic solvent) is 0.1% by weight or more.
• the specific amount of the organic solvent to be added varies depending on the type of the organic solvent and the type and amount of the polymerizable monomer for the shell, but is usually 0.1 to 100 parts by weight of the aqueous dispersion medium. It is from 1 to 50 parts by weight, preferably from 0.1 to 40 parts by weight, more preferably from 0.1 to 30 parts by weight.
• the order in which the organic solvent and the polymerizable monomer for sealing are added to the reaction system is not particularly limited, and the polymerization of the polymerizable monomer for shell is promoted to promote the transfer of the polymerizable monomer for shell to the core particles.
• the organic solvent it is preferable to add the organic solvent first, and then add the polymerizable monomer for the seal.
• the solubility in water at 20 ° C is firstly determined. 0.1% by weight or more of a monomer is added for polymerization, then an organic solvent is added, and then a monomer having a solubility in water at 20 ° C of less than 0.1% by weight is added and polymerized. This is preferred.
• the Tg of the polymer obtained from the monomer polymerized in the presence of the core particles and the amount of the monomer added are appropriately controlled. be able to.
• the polymerizable monomer for the shell is preferably used by mixing a charge control agent.
• a charge control agent By including a charge control agent in the seal, the chargeability of the polymerized toner can be improved.
• the charge control agent various positively or negatively chargeable charge control agents can be used. Specific examples of the charge control agent include Nigguchi Shin N01 (manufactured by Orient Chemical), Nigguchi Shin EX (manufactured by Orient Chemical), and Spiro black.
• the charge control agent is used in an amount of usually from 0.01 to 10 parts by weight, preferably from 0.1 to 5 parts by weight, based on 100 parts by weight of the polymerizable monomer for the core.
• a polymerizable monomer for shell is added to the reaction system of the polymerization reaction performed to obtain the core particles.
• the polymerizable monomer for Shul can be added to the reaction system all at once, or it can be added continuously or continuously using a pump such as a pranjam pump. it can.
• a water-soluble radical initiator at the time of adding the polymerizable monomer for a seal, in order to easily obtain core-shell type polymer particles.
• the water-soluble radical initiator is added when the polymerizable monomer for shell is added, the water-soluble radical initiator is added near the outer surface of the core particles to which the polymerizable monomer for shell has migrated. It is considered that this makes it easier to form a polymer layer (shell) on the surface of the core particles.
• the water-soluble radical initiator include persulfates such as potassium persulfate and ammonium persulfate; 4,4-azobis (4-cyanovaleric acid); and 2,2-azobis (2-amidino).
• Propane) dihydrochloride 2, 2-azobis 1 2-methyl-N-1, 1-bis (hydroxylmethyl) 1 2-azo system such as hydroxyxethyl propoamide
• an oil-soluble initiator such as cumene oxide and a redox catalyst; and the like.
• the amount of the water-soluble radical initiator to be used is usually 0.001-1% by weight based on the aqueous medium.
• the weight ratio of the polymerizable monomer for the core to the polymerizable monomer for the shell is usually 40 Z 60 to 99.9 / 0.1, preferably 60/40 to 99.5 / 0.5, more preferably 80Z20 to 99/1. If the proportion of the polymerizable monomer for the seal is too small, the effect of improving the storage stability is small, while if it is too large, the effect of decreasing the fixing temperature and the effect of improving the 0HP permeability are small.
• the polymerized toner of the present invention has a volume average particle diameter of usually 2 to 20 m, preferably 3 to 15 m, and a particle size distribution (volume average particle diameter / number average particle diameter) of usually 1.0. Spherical fine particles having a particle size distribution of 6 or less, preferably 1.5 or less.
• the polymerized toner of the present invention is a polymer particle having a core-to-seal structure comprising a core particle and a sealant covering the core particle.
• the average thickness of the shell in the core-shaped polymerized toner of the present invention is usually from 0.001 to l / zm, preferably from 0.005 to 0.5 m.
• the particle size and core thickness of the core particles in the polymerized toner can be determined by directly measuring the size and thickness of randomly selected particles from the observation photograph, if observable with an electron microscope. Obtainable.
• the thickness of the shell can be calculated from the particle diameter of the core particles and the amount of the monomer that forms the shell.
• the polymerized toner of the present invention has a toluene insoluble content of usually 50% by weight or less, preferably 20% by weight or less, and more preferably 10% by weight or less.
• Toluene-insoluble matter refers to the polymer remaining in the cage after the polymer component forming the polymerized toner is placed in a wire mesh basket of 80 mesh and immersed in toluene for 24 hours at room temperature. The product was dried in a vacuum drier, and the weight after drying was measured and expressed as a percentage by weight based on the polymer component.
• the ratio of the major axis r1 to the minor axis rs (r1 / rs) of the polymerized toner of the present invention is usually in the range of 1 to 1.2, preferably in the range of 1 to 1.15.
• this ratio is increased, the resolution of the image is reduced, and when the polymerized toner is placed in the toner storage section of the image forming apparatus, the friction between the polymerized toners increases.
• the external additives such as etc. tend to peel off and the durability tends to decrease.
• the polymerized toner of the present invention can be used as a developer as it is, but it can be used as a developer by adding various additives (external additives) such as a fluidizing agent as needed. Is also good. Additives usually adhere to the surface of the polymerized toner.
• the external additive include various inorganic particles and organic resin particles. Among these, silica particles and titanium oxide particles are preferred, and hydrophobically-treated silica particles are particularly preferred.
• the external additive and the polymerized toner are usually charged into a mixer such as a Henschel mixer and stirred.
• the fixing temperature can be reduced to a low temperature of 80 to 150 ° C, preferably 80 to 130 ° C, and the fixing temperature can be reduced during storage. Does not agglomerate and has excellent storage properties.
• Image forming device 80 to 150 ° C, preferably 80 to 130 ° C, and the fixing temperature can be reduced during storage. Does not agglomerate and has excellent storage properties.
• An image forming apparatus to which the polymerized toner of the present invention is applied includes a photoconductor (photosensitive drum), a unit for charging the surface of the photoconductor, a unit for forming an electrostatic latent image on the surface of the photoconductor, and a toner (developer). Means for supplying toner, developing the electrostatic latent image on the photoreceptor surface to form a toner image, and means for transferring the toner image from the photoreceptor surface to a transfer material. It has the following.
• FIG. 1 shows a specific example of such an image forming apparatus.
• a photosensitive drum 1 as a photosensitive member is mounted on the image forming apparatus so as to be rotatable in the direction of arrow A.
• the photosensitive drum 1 has a photoconductive layer provided on the outer peripheral surface of a conductive support drum.
• the photoconductive layer is composed of, for example, an organic photoreceptor, a selenium photoreceptor, a zinc oxide photoreceptor, and an amorphous silicon photoreceptor.
• a charging roll 2 as charging means, a laser-light irradiating device 3 as latent image forming means, and a developing means as current image means.
• a development roll 4, a transfer port 10 as a transfer means, and a cleaning device (not shown) are provided as required.
• the charging roll 2 is for uniformly charging the surface of the photosensitive drum 1 positively or negatively.
• the surface of the photosensitive drum 1 is charged by applying a voltage to the charging roll 2 and bringing the charging roll 2 into contact with the surface of the photosensitive drum 1.
• Charging roll 2 can be replaced by charging means by corona discharge.
• the laser light irradiator 3 irradiates the surface of the photosensitive drum 1 with light corresponding to the image signal, and irradiates the uniformly charged surface of the photosensitive drum 1 with a predetermined pattern.
• To form an electrostatic latent image on the part irradiated with light in the case of reversal development, or an electrostatic latent image on the part not irradiated with light. (In case of regular development).
• As another latent image forming means there is a means composed of an LED array and an optical system.
• the developing roll 4 is for attaching toner to the electrostatic latent image of the photosensitive drum 1. In reverse development, the toner is attached only to the light-irradiated portion, and in regular development, the light-irradiated portion is not attached. A bias voltage is applied between the developing roll 4 and the photosensitive drum 1 so that the toner adheres only to the photosensitive drum 1.
• a developing roll 4 and a supply roll 6 are provided in a casing 9 in which the toner 7 is stored.
• the developing roll 4 is disposed close to the photosensitive drum 1 so as to partially contact the photosensitive drum 1, and rotates in a direction B opposite to the photosensitive drum 1.
• the supply roll 6 contacts the developing roll 4 and rotates in the same direction C as the developing roll to supply toner to the outer periphery of the developing roll 4.
• a stirring means (stirring blade) 8 for stirring the toner is installed in the casing 9.
• a developing roll blade 5 as a layer thickness regulating means is arranged around the developing roll 4 between a point of contact with the supply roll 6 and a point of contact with the photosensitive drum 1.
• This blade 5 is made of conductive rubber stainless steel, and is normally charged with a voltage of
• the case 9 of the image forming apparatus contains the polymerized toner 7 of the present invention.
• the polymerized toner 7 may have an additive such as a fluidizing agent attached thereto.
• the polymerized toner of the present invention has a core-shell type structure, and the shell of the surface layer is a polymer having a relatively high glass transition temperature. Since it is formed of, the surface has low tackiness and is prevented from aggregating in the casing 9 during storage. Further, since the polymerization toner of the present invention has a relatively short particle size distribution, when the toner layer is formed on the development roll 4, the toner thickness is substantially controlled by the layer thickness regulating means 5. Specifically, it can be made into a single layer, thereby improving the reproducibility of the image.
• the transfer roll 10 is for transferring a toner image formed on the surface of the photosensitive drum 1 by the developing roll 4 onto the transfer material 11.
• Examples of the transfer material 11 include paper and resin sheets such as 0HP sheets.
• a corona discharge device and a transfer belt can be used as the transfer means.
• the toner image transferred onto the transfer material 11 is fixed on the transfer material by fixing means.
• the fixing means usually comprises a heating means and a pressure bonding means. More specifically, the fixing means is usually composed of a combination of a heating roll (fixing roll) 12 and a pressure roll 13.
• the transfer material 11 onto which the toner image has been transferred is passed between the heating port 12 and the pressure port 13 to melt the toner, and at the same time, is pressed onto the transfer material 11 to be solidified.
• the toner can be easily melted even if the heating temperature by the heating means is low, and if the toner is pressed lightly by the pressing means, the toner is Since it is fixed to the transfer material surface in a smooth state, high-speed printing or copying is possible. Further, the toner image fixed on the 0 HP sheet has excellent 0 HP transmissivity.
• the cleaning device is for cleaning the transfer residual toner remaining on the surface of the photosensitive drum 1, and is, for example, a cleaning blade or the like. Be composed.
• the cleaning device does not necessarily need to be installed if a method of performing cleaning at the same time as development using the developing roll 4 is adopted.
• an image forming method includes a step of attaching a toner to a surface of a photoreceptor on which an electrostatic latent image is formed to form a visible image, and then transferring the visible image to a transfer material.
• the polymerized toner of the present invention is used as the toner.
• the volume average particle size (dv) of the polymer particles, and the particle size distribution, ie, the ratio of the volume average particle size to the number average particle size (dp) (dv / dp), are determined by the Multi-Sizer (manufactured by Coulter Corporation). It was measured more. The measurement by this multisizer was performed under the following conditions: one diameter of the aperture: 50 ⁇ m, the medium: Isoton II, and the number of particles measured: 500,000.
• the shell thickness was calculated using the following equation.
• Shell thickness ( ⁇ m) dr (1 + s / 100) 1/3 — dr
• dr is the radius of the core particle before addition of the polymerizable monomer for the shell (1/2 of the volume average particle size obtained by measurement with a multisizer
• s is the polymerization of the shell.
• reactive monomer parts based on 100 parts by weight of the polymerizable monomer for the core).
• the volume resistivity of the toner was measured using a dielectric loss measuring device (trade name: TRS-10, manufactured by Ando Electric Co., Ltd.) at a temperature of 30 ° C and a frequency of 1 kHz.
• a commercially available non-magnetic one-component developing printer (four-sheet machine) was modified so that the temperature of the fixing unit can be changed.
• This modified printer was used to evaluate toner images.
• the temperature at a fixing rate of 80% was evaluated as the fixing temperature.
• the fixing test was performed by changing the temperature of the fixing roll of the printer, measuring the fixing rate at each temperature, and determining the relationship between the constant temperature fixing rates.
• the fixation rate was calculated from the ratio of the image density before and after the tape peeling operation in the solid black area of the test paper printed with the modified printer. Assuming that the image density before tape peeling is ID and the image density after tape peeling is after ID, the fixing rate is obtained from the following equation.
• Fixing rate (%) (after ID / before ID) X I 0 0
• the solid black region is a region controlled so that toner is attached to all of the dots in the region.
• the tape peeling operation is to apply an adhesive tape (Scout Mending Tape 8110-3-18 made by Sumitomo 3M) on the measurement part of the test paper, and extrude it at a constant pressure to adhere. After that, it is a series of operations to peel off the adhesive tape at a constant speed in the direction along the paper.
• the image density was measured using a reflection image densitometer manufactured by McBeth. (5) Conservation of toner
• the toner sample placed in a sealed container, seal it, submerge it in a thermostatic water bath whose temperature is controlled at 55 ° C, remove it after a certain period of time, and aggregate it. This was done by weighing the toner.
• the sample removed from the container was transferred onto a 42-mesh sieve so as not to destroy the structure as much as possible, and the vibration intensity was adjusted using REOSTAT of a powder measuring machine (manufactured by Hosokawa Miclon). After setting to .5 and vibrating for 30 seconds, the weight of the toner remaining on the sieve was measured and determined as the weight of the aggregated toner.
• the aggregation rate (% by weight) of the toner was calculated from the weight of the aggregated toner and the number of samples.
• the storage stability of the toner was evaluated on the following four scales.
• ⁇ aggregation rate is less than 5% by weight
• the aggregation rate is 5% by weight or more and less than 10% by weight
• the aggregation rate is 10% by weight or more and less than 50% by weight
• the aggregation rate is 50% by weight or more.
• the temperature of the fixing roll of the modified printer was set to 150 ° C, and printing was performed using a commercially available 0 HP (Transfer Lance 1) sheet by Uchida Yoko Co., Ltd. Was evaluated for 0 HP permeability. It was visually observed whether or not the print penetrated the 0 HP sheet, and the transmission ( ⁇ ) or opacity (X) was evaluated.
• 0 HP Transfer Lance 1
• the charge amount of the toner is determined by using a commercially available printer (4 sheets). After leaving the toner for one day and night, print five halftone print patterns, and then suck the toner on the developing roll into the suction-type charge-amount measuring device to determine the charge amount and the suction amount. The charge amount per unit weight was measured.
• the particle size of the polymerizable monomer droplets for the shell was determined by adding the resulting droplets to a 1% aqueous sodium hydroxide solution at a concentration of 3%. click diameter this filtrate and was measured with a distribution analyzer, D 9 Q force 1. was Tsu 6 m der.
• magnesium hydroxide colloid a colloid of a poorly water-soluble metal hydroxide.
• the resulting particle size distribution of the co-Roy de was determined by microphone collected by filtration rack particle size distribution measuring apparatus (manufactured by Nikkiso Co., Ltd.), particle size, 50% cumulative D CQ (number size distribution Value) was 0.38 m, and D g Q (90% cumulative value of the number particle size distribution) was 0.82 m.
• the measurement range was 0.12 to 704 ⁇ m
• the measurement time was 30 seconds
• the medium was ion-exchanged water.
• the polymerizable monomer composition for a core is added to the magnesium hydroxide colloid dispersion liquid obtained as described above, and high shearing is performed at 1200 rpm using a TK homomixer. By stirring, droplets of the core polymerizable monomer composition were granulated.
• the aqueous dispersion of the granulated monomer composition was placed in a reactor equipped with stirring blades, and the polymerization reaction was started at 90 ° C. When the polymerization conversion reached approximately 100%, Then, the polymerizable monomer for shell and 1 part of a 1% aqueous solution of potassium persulfate were added, and the reaction was continued for 5 hours. Thereafter, the reaction was stopped, and water of the core-shell type polymer particles was removed. A dispersion was obtained.
• the determined volume average particle diameter (dv) was 5.7 m
• the volume average particle diameter (dV) / number average particle diameter (dp) was 1.32.
• the thickness of the seal was 0.09 ⁇ m
• the rl / rs was 1.1
• the toluene insoluble content was 2%.
• a hydrophobized colloid Darsilica (trade name: R-972, manufactured by Nippon Aerosil) was added. The mixture was added and mixed using a Hensyl mixer to prepare a non-magnetic one-component developer (hereinafter simply referred to as developer or toner).
• developer or toner a non-magnetic one-component developer
• Example 3 Polymerized toner and a developer (toner) were obtained in the same manner as in Example 1 except that the amount of pentaerythritol tetrastearate used in Example 1 was changed to 5 parts. . In the image evaluation, an image having a high image density, no force, no blur, and an extremely good resolution was obtained. Table 1 shows the results. [Example 3]
• Example 1 Except that the pentaerythritol tetrastearate used in Example 1 was changed to glycerol triacetate (arachinic acid purity about 60%), In the same manner as in Example 1, a polymerized toner and a developer (toner) were obtained. Table 1 shows the results.
• Pentaerythritol tetrastearate used in Example 1 had a melting point of 60.
• a polymerized toner and a developer (toner) were obtained in the same manner as in Example 1 except that the paraffin wax of C was used. Table 1 shows the results.
• Example 1 The same procedures as in Example 1 were carried out except that the pentaerythritol-l-tetrastearate used in Example 1 was replaced with a low-molecular-weight polypropylene having a number-average molecular weight of 222. Thus, a polymerized toner and a developer (toner) were obtained. Table 1 shows the results.
• Example 1 was repeated except that 10 parts of methyl methacrylate used in the polymerizable monomer for sealing were replaced with 9 parts of methyl methacrylate and 1 part of butyl acrylate in Example 1.
• a polymerized toner and a developer (toner) were obtained in the same manner as in Example 1. Table 2 shows the results.
• Example 1 10 parts of styrene were used instead of 10 parts of methyl methacrylate used for the polymerizable monomer for sealing, and immediately before adding the polymerizable monomer for sealing.
• Polymerized toner and a developer (toner) were obtained in the same manner as in Example 1 except that 20 parts of methanol was added to the mixture. Table 2 shows the results.
• Example 1 instead of the t-butyloxy1-2-ethylhexanoate used as the polymerization initiator for the polymerizable monomer for the core, 2,2-azobisisobutyronitrile was used. Polymerized toner and developer in the same manner as in Example 1 except that the reaction temperature was changed to 75
• a polymerized toner and a developer (toner) were obtained in the same manner as in Example 1, except that the polymerizable monomer for a seal was added without performing an ultrasonic emulsifier treatment in Example 1. .
• Table 2 shows the results. Table 2
• a polymerized toner and a developer (toner) were prepared in the same manner as in Example 1 except that the butyl acrylate used for the polymerizable monomer for the core was changed to 2-ethylhexyl acrylate. ) Got. Table 3 shows the results.
• Example 3 shows the results.
• Example 3 In the same manner as in Example 1 except that 5 parts of cyan pigment (Vigmentable 15: 3) was used instead of 7 parts of carbon black, the polymerization toner and A developer (toner) was obtained. Table 3 shows the results.
• a polymerized toner was prepared in the same manner as in Comparative Example 1 except that in Example 1, 5 parts of magenta pigment (a pigment red 122) were used instead of 7 parts of carbon black. A toner and a developer (toner) were obtained. Table 3 shows the results.
• Example 1 the procedure was the same as in Example 1 except that pentaerythritol monotrate was used instead of pentaerythritol tetrastrate. Thus, a polymerized toner and a developer (toner) were obtained.
• the volume average particle size (dV) measured by taking out the core particles immediately before adding the polymerizable monomer for shell was 5.8 ⁇ m, and the volume average particle size (dV)
• the volume resistivity of the non-magnetic one-component developer (toner) obtained by adding a colloidal force to the polymerized toner obtained by subjecting it to a hydrophobizing treatment was 11.3 log ⁇ ⁇ cm.
• pentaerythritol tetrastrate Compared with pentaerythritol tetrastrate, pentaerythritol tetrastrate has a higher solubility in polymerizable monomers and a higher room temperature. There was no need to grind or melt in advance to increase the solubility in the melt.
• the use of the polymerized toner of the present invention enables high-speed copying and printing, full colorization, and energy saving.
• the polymerized toner of the present invention shows excellent transparency when printed on a 0 HP sheet and fixed.
• the polymerization toner of the present invention can form a high-quality image without fogging or a decrease in print density.
• an image forming method using a polymerized toner having such excellent characteristics, and an image forming apparatus containing the polymerized toner there is provided.

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• 1997
  • 1997-10-31 EP EP08106032A patent/EP2042932A1/de not_active Withdrawn
  • 1997-10-31 WO PCT/JP1997/003972 patent/WO1998020396A1/ja active IP Right Grant
  • 1997-10-31 KR KR10-1999-7003934A patent/KR100533491B1/ko not_active IP Right Cessation
  • 1997-10-31 DE DE69739222T patent/DE69739222D1/de not_active Expired - Lifetime
  • 1997-10-31 EP EP97909708A patent/EP0952495B1/de not_active Expired - Lifetime
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