JP2003207945A - Black toner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide toner which does not cause irregularities in image quality even in the case of outputting images for a long period of time, and keeps excellent gloss. <P>SOLUTION: In the toner having at least binding resin, a colorant, and a kind of or several kinds of additives, the value of the melt index of the toner is 5 to 30 and a gel component is 5 to 50%. In a kind of optional additive, assuming that the volume average voltage of toner particles which synchronize with the additive is α and that of toner particles which does not synchronize with the additive is β, β/α is 0 to 1, and assuming that a counted number at the median voltage of the toner particles which synchronize with the additive is γ and that of the toner particles which does not synchronize with the additive is δ, δ/γ is 0 to 0.5. The black toner is used for a full color machine. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toner used in a recording method using an electrophotographic method, an electrostatic recording method, a toner jet recording method, or the like. More specifically, the present invention relates to a color toner used in a copying machine, a printer or a fax machine in which a toner image is previously formed on an electrostatic latent image carrier and then transferred onto a transfer material to form an image.

[0002]

2. Description of the Related Art Conventionally, as an electrophotographic method, U.S. Pat. No. 2,297,691 and JP-B-42-23910 are known.
Publication (US Pat. No. 3,666,363) and Japanese Patent Publication No. 43-24748 (US Pat. No. 4,074)
1,361) and many other methods are known. Generally, a photoconductive substance is used to form an electric latent image on the electrostatic latent image carrier by various means, and then the electrostatic latent image is developed with toner to form a visible image, and if necessary, After the toner image is transferred to a transfer material such as paper, the toner image is fixed on the transfer material by heat, pressure or the like to obtain a copy.

In recent years, demands for image quality of images output by electrophotographic copying machines, printers and the like have become higher than ever before. Especially for color copiers / printers, the demand for image quality is high. Further, due to the high performance of computers, there is an increasing demand to visualize higher quality images at higher speed. Various studies have been made to satisfy this, but the reality is that none have been obtained.

One of the problems is the gloss of the fixing surface. This is the gloss of the fixing surface when the toner is fixed on paper or OHP film. If this gloss is high, the surface will be glaring, making it difficult to see images and characters, and in severe cases causing eye strain. Will be. However, if the gloss is low, the aesthetic appearance of images such as photographs may deteriorate. And this requirement is particularly noticeable for full-color images.

In order to improve these, a method has been proposed in which the amount of the release agent is increased or oil is applied at the time of fixing to produce gloss, but with the increase of the release agent, there is a possibility that the contamination in the machine becomes severe. However, there are drawbacks such as the cost of applying oil at the time of fixing is high and the volume of the machine is large. In order to improve these problems, JP-A-9-10610
Improvements have been attempted in Japanese Patent Laid-Open No. 5 and Japanese Patent Laid-Open No. 10-133422, but with recent improvements in image quality and speed,
With these improvements, durability becomes difficult.
In order to improve these, the release rate of the external additive was controlled to improve the image quality as in JP-A-11-258847 and JP-A-2000-292966. It was difficult to maintain good gloss and high image quality for a long period of time.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to provide a toner which solves the above-mentioned problems of the prior art and does not disturb the image quality even when an image is output for a long period of time and maintains good gloss. .

[0007]

The above object can be achieved by the present invention described below.

That is, the present invention provides a toner having at least a binder resin, a colorant, and one or more external additives, and the melt index value of the toner is 5 to 5.
30, a toner having a gel content of 5 to 50%, and in any one kind of external additive, the volume average voltage of toner particles synchronized with the external additive is α, toner not synchronized with the external additive Β / α is 0 to 1 where β is the volume average voltage of the particles, γ is the count number at the median voltage of the toner particles synchronized with the external additive, and toner is not synchronized with the external additive When the count number at the median voltage of particles is δ, δ / γ is 0
The present invention relates to a black toner used in a full-color machine characterized by being 0.5.

[0009]

DETAILED DESCRIPTION OF THE INVENTION As a result of intensive studies by the present inventors, in a toner containing at least a binder resin, a colorant, and one or more kinds of external additives, the melt index value of the toner is 5 to 5. 30 and the gel content is 5 to 50
%, Β / α is 0 to 1, where α is the volume average voltage of the toner particles to which the external additive is attached and β is the volume average voltage of the toner particles to which the external additive is not attached. Δ / γ is 0 to 0.5 where γ is the count number of the toner particles to which the toner particles are attached and δ is the count number of the toner particles to which the external additive is not attached. It has been found that by doing so, the gloss of the surface of the fixed image can be improved, and offset, winding around the fixing device, and fusion with the electrostatic latent image carrier can be prevented, and good image quality can be maintained for a long period of time.

The details will be described below.

The preferred range of gloss on the surface of a fixed image cannot be generally stated because it depends on the ambient brightness at the time of viewing the image and personal preference, but the reflection at the time of viewing a solid image. From the amount of light and the like, it is considered that the gloss of black is preferably about 5 to 70. Then, if it is less than this range, the color will sink only in black when a full-color image is formed. However, if you reduce the gloss of the entire image, you can balance the gloss of all colors, but OH
When it is fixed on the P film, the light transmission is poor,
The problem occurs that a clear and sharp image cannot be obtained. Further, if the black gloss exceeds 70, the image becomes glaring and becomes difficult to see. On the other hand, the toner of the present invention has a melt index value of 5 to 30.
By so doing, the toner particles are easily melted, and the gloss is adjusted to an appropriate range.

However, if the toner particles are left as they are, the toner particles are easily melted, so that high-temperature offset and winding around the fixing device are likely to occur, and embedding of the external additive is likely to occur. As a result, when an image is displayed for a long period of time, the fluidity of the toner deteriorates, which may cause image deterioration such as fog or toner dripping.

Therefore, regarding the high-temperature offset and the winding around the fixing device, the high-temperature offset and the winding around the fixing device could be prevented by setting the gel content to 5 to 50%.

Regarding image deterioration when an image is displayed for a long period of time, the count number at the median voltage of the toner particles to which the external additive is attached is γ, and the median of the toner particles to which the external additive is not attached is γ. By setting δ / γ when the number of counts at voltage is δ to 0 to 0.5, it was possible to secure the fluidity of the toner and prevent fog and dripping. Further, regarding fusion to the electrostatic latent image carrier, when the volume average voltage of the toner particles to which the external additive is attached is α and the volume average voltage of the toner particles to which the external additive is not attached is β Β /
It could be prevented by setting α to 0 to 1.

Next, constituent elements of the present invention will be described.

In the present invention, it is possible to incorporate inorganic fine particles on the toner surface as an external additive for the toner.

As the inorganic fine particles, magnesium, zinc,
Oxide powder of aluminum, titanium, cobalt, zirconium, manganese, cerium, strontium, etc. and complex metal oxide powder of calcium titanate, magnesium titanate, strontium titanate, barium titanate, etc., boron, silicon, titanium Carbides such as vanadium, zirconium, molybdenum, and tungsten; carbonates, sulfates, phosphates, etc., such as magnesium, calcium, strontium, and barium.

Of these, silica fine particles are preferable for improving fluidity, and magnesium is preferably contained on the toner surface for maintaining chargeability.

Among the silica fine particles, particularly preferable ones are so-called dry method produced by vapor phase oxidation of a silicon halogen compound or dry silica called fumed silica, and so-called wet silica produced from water glass or the like. Both can be used, but there are few silanol groups on the surface and inside the silica fine particles, and Na ₂ O, S
Dry silica, which has no production residue such as O ₃ ²⁻ , is preferable.

Further, in the case of dry silica, it is possible to obtain composite fine particles of silica and other metal oxide by using other metal halogen compound such as aluminum chloride or titanium chloride together with the silicon halogen compound in the manufacturing process. Yes, and include them.

The silica fine particles used in the present invention are, if necessary, surface-treated with a treating agent such as a silane coupling agent or an organic silicon compound for the purpose of hydrophobizing and controlling triboelectric charging properties. Any known method may be used, and the surface treatment is performed with a treating agent that reacts with or physically adsorbs to the silica particles.

Examples of such treating agents include hexamethyldisilazane, trimethylsilane, trimethylchlorosilane, trimethylethoxysilane, dimethyldichlorosilane, methyltrichlorosilane, allyldimethylchlorosilane, allylphenyldichlorosilane and benzyl. Dimethylchlorosilane, bromomethyldimethylchlorosilane, α-chloroethyltrichlorosilane, β-chloroethyltrichlorosilane, chloromethyldimethylchlorosilane, triorganosilylmercaptan, trimethylsilylmercaptan, triorganosilylacrylate, vinyldimethylacetoxysilane, dimethylethoxy Silane, dimethyldimethoxysilane, diphenyldiethoxysilane, hexamethyldisiloxane, 1,3-divinyltetramethyl Disiloxane, 1,3-diphenyltetramethyldisiloxane, and 2 to 12 per molecule
For example, there is dimethylpolysiloxane having siloxane units and each terminal unit having a hydroxyl group bonded to Si. These are used alone or as a mixture of two or more.

Hydrotalcite compounds are preferred as the magnesium used in the external additive of the present invention. The hydrotalcite compound has the following structural formula.
Mg _1-X Al _X (OH) ₂ (CO ₃ ) _{X / 2} · mH ₂ O (0 <
X ≦ 0.5)

The reason why this hydrotalcite compound is effective is not clear, but it is considered that its charging property has a great influence.

The inorganic fine particles used in the present invention may be surface-treated with silicone oil. A known method is used for the surface treatment of the silicone oil. For example, the inorganic fine powder and the silicone oil may be directly mixed by using a mixer such as a Henschel mixer, or the base fine powder may be mixed with the silicone oil. You may use the method of spraying. Alternatively, a method may be used in which after dissolving or dispersing silicone oil in a suitable solvent, inorganic fine powder is added and mixed, and the solvent is removed. As the silicone oil used in the present invention, known ones are used, and for example, dimethyl silicone oil, methylphenyl silicone oil, α-methylstyrene modified silicone oil, chromium phenyl silicone oil, fluorine modified silicone oil and the like are used. .

As other external additives, conventionally known external additives such as various metals and oxides thereof, complex metal oxides, silica, resin fine particles, and their surface-treated products can be arbitrarily used. At this time, the total amount of external additives added is preferably 0.05 to 5 parts by mass per 100 parts by mass of the toner base particles. If the amount added is less than 0.05 parts by mass, the fluidity of the toner particles may be poor, and spillage or the like may occur. There is a risk of fusion. And a more preferable range is 0.1 to 3 parts by mass.

In the present invention, wax may be added if necessary. The wax is obtained from the following waxes. Paraffin wax and its derivatives, montan wax and its derivatives, microcrystalline wax and its derivatives, Fischer-Tropsch wax and its derivatives, polyolefin wax and its derivatives, etc., where the derivatives are oxides and block copolymers with vinyl monomers. , Including graft modified products. Examples of the polyolefin waxes include linear α-olefins such as ethylene, propylene, butene, pentene, hexene, heptene, octene, nonene and decene, and branched α-olefin homopolymers and copolymers.

In addition, alcohols, fatty acids, acid amides,
It is possible to use esters, ketones, hydrogenated castor oil and its derivatives, vegetable waxes, animal waxes, mineral waxes, petrolactam and the like.

The content of wax is 0.3 to 30% by mass, more preferably 0.5 to 20% by mass.

As the binder resin of the toner usable in the present invention, generally known resins can be used. For example, styrenes such as styrene, α-methylstyrene, p-chlorostyrene and the like, and substitution products thereof; acrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate, dodecyl acrylate, octyl acrylate, phenyl acrylate,
Monocarboxylic acids having double bonds such as methacrylic acid, methyl methacrylate, ethyl methacrylate, butyl methacrylate, octyl methacrylate, acrylonitrile, methacrylonitrile, diethylaminoethyl acrylate, diethylaminoethyl methacrylate, acrylamide and the like Substitutes; for example, dicarboxylic acids having a double bond such as maleic acid, butyl maleate, methyl maleate, dimethyl maleate and the like; substitutes therefor; vinyls such as vinyl chloride, vinyl acetate, vinyl benzoate or the like. Vinyl esters, or polymers using vinyl monomers such as vinyl ethers such as vinyl ethyl ether, vinyl methyl ether, vinyl isobutyl ether and the like, or copolymers using two or more kinds;
Further, styrene-butadiene copolymer, silicone resin, polyester resin, polyurethane, polyamide, epoxy resin, polyvinyl butyral, rosin, modified rosin, terpene resin, phenol resin, aliphatic or alicyclic hydrocarbon resin, aromatic petroleum Resin, chlorinated paraffin, etc .; these can be used alone or in combination of two or more kinds.

Among these binder resins, in the present invention, it is preferable that a styrene resin is contained as the binder resin. The styrene-based resin is preferable because its main chain has a low polarity and the toner charge control by the constitution of the external additive of the present invention works more effectively. Considering the viscoelasticity and melting characteristics of the resin, a styrene-acrylic resin copolymerized with an acrylic monomer is the most preferable, and it is preferable to contain 50% or more of the binder resin component as the main component.

Further, the binder resin used in the present invention includes
In order to adjust the fixing temperature of the toner, it is possible to contain a crosslinkable polymerizable monomer exemplified below.

As the crosslinkable polymerizable monomer, a polymerizable monomer having two or more polymerizable double bonds is mainly used. Specific examples include bifunctional crosslinking agents such as divinylbenzene, divinylnaphthalene, bis (4-acryloxypolyethoxyphenyl) propane, ethylene glycol diacrylate, 1,3-butylene glycol diacrylate, 1,4-butane. Diol diacrylate, 1,5-pentanediol diacrylate, 1,6
-Hexanediol diacrylate, neopentyl glycol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol # 200, # 400, # 600 diacrylates, dipropylene glycol diacrylate, polypropylene Examples thereof include glycol diacrylate, polyester type diacrylate (MANDA Nippon Kayaku), and those obtained by replacing the above acrylates with methacrylates.

The toner of the present invention is preferably a non-magnetic one-component toner.

Unlike the two-component developing method, the one-component developing method does not require carrier particles such as glass beads, iron powder, and ferrite, so that the developing device itself can be made compact and lightweight. Further, in the two-component developing method, it is necessary to keep the toner concentration in the developer constant, so that a device for detecting the toner concentration and replenishing a required amount of toner is required, which leads to an increase in size and weight of the developing device. Also in this respect, the one-component developing method is advantageous because it is advantageous for downsizing and weight saving.

The one-component developing method is roughly classified into a magnetic one-component developing method using a magnetic toner containing a magnetic substance in the toner and a non-magnetic one-component developing method not using a magnetic substance. A non-magnetic one-component developing method that can use color toners is preferable.

In the present invention, a charge control agent may be added if necessary.

The following substances control the toner to be negatively charged.

For example, organic metal compounds and chelate compounds are effective, and there are monoazo metal compounds, acetylacetone metal compounds, aromatic hydroxycarboxylic acids, and aromatic dicarboxylic acid metal compounds. Other examples include aromatic hydroxycarboxylic acids, aromatic mono- and polycarboxylic acids and their metal salts, anhydrides, esters, and phenol derivatives such as bisphenol. Further, urea derivatives, metal-containing salicylic acid compounds, metal-containing naphthoic acid compounds, boron compounds, quaternary ammonium salts, calixarene, silicon compounds, styrene-acrylic acid copolymers, styrene-methacrylic acid copolymers, styrene- Examples thereof include acrylic-sulfonic acid copolymers and non-metal carboxylic acid compounds.

Further, there are the following substances for controlling the toner to be positively charged.

For example, modified products of nigrosine and fatty acid metal salts, guanidine compounds, imidazole compounds,
Tributylbenzyl ammonium-1-hydroxy-4
Naphthosulfonates, quaternary ammonium salts such as tetrabutylammonium tetrafluoroborate, and onium salts such as phosphonium salts, which are analogs thereof, lake pigments thereof, triphenylmethane dyes and lake pigments thereof (lake formation) As agents, phosphotungstic acid, phosphomolybdic acid, phosphotungstic molybdic acid, tannic acid, lauric acid, gallic acid, ferricyanide, ferrocyanide, etc.), metal salts of higher fatty acids; dibutyltin oxide, dioctyltin oxide, dicyclohexyl Diorganotin oxides such as tin oxide; Diorganotinborates such as dibutyltin borate, dioctyltin borate and dicyclohexyltin borate; Use of these alone or in combination of two or more It can be.

Further, when the direct polymerization method is used in the present invention, a charge control agent having no polymerization inhibitory property and having no solubilized product in an aqueous system is particularly preferable. As specific compounds, salicylic acid, naphthoic acid, metal compounds of dicarboxylic acid, sulfonic acid, polymeric compounds having carboxylic acid in the side chain, boron compounds, urea compounds, silicon compounds, currys arenes, etc. A quaternary ammonium salt, a polymer type compound having a side chain of the quaternary ammonium salt, a guanidine compound, an imidazole compound, or the like is preferably used as a positive system. The charge control agent is preferably 0.5 to 10 parts by mass with respect to 100 parts by mass of the resin.

The toner of the present invention is a full-color black toner, and as the colorant used, a black colorant such as carbon black or magnetite, or any conventionally known pigment and / or dye can be used.

The method for producing the toner base of the present invention includes:
Henschel mixer, ball mill,
Mixing process using a V-type mixer or other mixer, kneading process using a heat kneader such as a heat roll kneader or an extruder, crushing process after cooling and solidifying the kneaded product, crushing process using a crusher such as a jet mill, crushing There is a method in which a product is manufactured through a classification process.

As another method, there is a method in which a component containing a monomer, a colorant and the like is granulated and polymerized, and then manufactured. The toner of the present invention is particularly preferable when it is manufactured through a step of granulating / polymerizing a component containing at least a monomer and a colorant as a manufacturing step thereof. The toner produced by this production method has a smooth surface, and since the fluidity of the toner is improved, it is effective in preventing toner deterioration when an image is displayed for a long period of time. It is also possible to add an external additive such as silica during the preparation of the toner base, which is preferable because the dispersion of the external additive becomes good.

The above-mentioned toner base may be polymerized in the presence of an initiator, the presence of a crosslinking agent, or the absence thereof.

As the polymerization initiator, di-t-butyl peroxide, benzoyl peroxide, lauroyl peroxide, t-butyl peroxylaurate, 2,
2'-azobisisobutyronitrile, 1,1-bis (t
-Butylperoxy) 3,3,5-trimethylcyclohexane, 1,1-bis (t-butylperoxy) cyclohexane, 1,4-bis (t-butylperoxycarbonyl) cyclohexane, 2,2-bis (t -Butylperoxy) octane, n-butyl 4,4-bis (t-butylperoxy) valerate, 2,2-bis (t-butylperoxy) butane, 1,3-bis (t-butylperoxy)- Isopropyl) benzene, 2,5-dimethyl-
2,5-di (t-butylperoxy) hexane, 2,5
-Dimethyl-2,5-di (t-butylperoxy) hexane-3,2,5-dimethyl-2,5-di (benzoylperoxy) hexane, di-t-butylperoxyisophthalate, 2,2 -Bis (4,4-di-t-butylperoxycyclohexyl) propane, di-t-butylperoxy α-methylsuccinate, di-t-butylperoxydimethylglutarate, di-t-butylperoxyhexa Hydroterephthalate, di-t-butylperoxyazelate, 2,5-dimethyl-2,5-di (t-
Butyl peroxy) -hexane, diethyl glycol-
Bis (t-butyl peroxycarbonate), di-t-
Butyl peroxytrimethyl adipate, triazine,
Mention may be made of tris (t-butylperoxy) triazine, vinyltruri (t-butylperoxy) silane, cumin perpivalate, dicumyl peroxide, azobis-isobutyronitrile and dimethylazoisobutyrate.

The above-mentioned polymerization initiators can be used alone or as a mixture in consideration of the amount used, the polymerization temperature and the half-life.

The amount of the polymerization initiator added varies depending on the desired degree of polymerization, but it is generally used in an amount of 0.5 to 20% by mass based on the monomer. Further, in order to control the degree of polymerization, known cross-linking agents, chain transfer agents, polymerization inhibitors, etc. may be added and used.

As the dispersant used in the present invention, a general dispersant can be used, and in some cases, a suitable stabilizer can be used in combination. For example, as an inorganic compound, tricalcium phosphate, magnesium phosphate, aluminum phosphate, zinc phosphate, calcium carbonate, magnesium carbonate, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, calcium metasilicate, calcium sulfate, barium sulfate. -Bentonite, silica, alumina, etc. may be mentioned. As organic compounds, polyvinyl alcohol, gelatin, methyl cellulose, methyl hydroxypropyl cellulose, ethyl cellulose, sodium salt of carboxymethyl cellulose,
Polyacrylic acid and its salt, starch, etc. can be used by dispersing in an aqueous phase. This dispersant is preferably used in an amount of 0.2 to 2.0 parts by mass with respect to 100 parts by mass of the polymerizable monomer. Also, because of the fine dispersion of these dispersants,
You may use together 0.001-0.1 mass part of stabilizers, such as surfactant. This is to promote the desired action of the above dispersant, and specific examples thereof include sodium dodecylbenzene sulfate / sodium tetradecyl sulfate.
Examples include sodium pentadecyl sulfate, sodium octyl sulfate, sodium oleate, sodium laurate, potassium stearate, calcium oleate, and the like.

A specific method for producing the toner in the present invention is, for example, the following method.

That is, a releasing agent, a colorant, a charge control agent, a polymerization initiator and other additives made of a substance having a low softening point are added to the polymerizable monomer, and the mixture is homogenized by a homogenizer, an ultrasonic disperser or the like. Dissolved or dispersed monomer system, a normal stirrer or homomixer in the aqueous phase containing the dispersion stabilizer,
Disperse with a homogenizer. Preferably, the stirring speed and time are adjusted so that the monomer droplets have a desired toner particle size, and granulation is performed. After that, stirring may be performed to such an extent that the particle state is maintained by the action of the dispersion stabilizer and the particles are prevented from settling.

Polymerization temperature is 40 ° C. or higher, generally 50 ° C.
It is preferable to carry out the polymerization by setting the temperature at 90 ° C. Also,
The temperature may be raised in the latter half of the polymerization reaction, and further in the latter half of the reaction or after completion of the reaction in order to remove unreacted polymerizable monomer, by-product, etc. which may cause odor during fixing of the developer. Part of the aqueous medium may be distilled off. In the suspension polymerization method, it is usually preferable to use 300 to 3000 parts by mass of water as a dispersion medium based on 100 parts by mass of the monomer system.

The toner of the present invention has a melt index (MI) in the range of 5 to 30 g / 10 minutes and 7 to 20.
g / 10 minutes is more preferable. Melt index is 30
If it is higher than g / 10 minutes, wrapping around the fixing device or high-temperature offset may occur, and when used in a non-magnetic one-component developing system, the toner carrier and the developing blade rub against each other. In this case, the toner particles are significantly fused to the upper surface of the developing blade, and the fused material causes coating unevenness in the toner coat layer on the carrier, which results in development unevenness and streaks on the image, which is not preferable. Further, if the melt index is less than 5 g / 10 minutes, the fixing temperature becomes too high, and therefore the temperature inside the apparatus becomes too high due to the increase in power consumption of the fixing apparatus and the temperature rise inside the apparatus, and the toner inside the toner container deteriorates. There is a fear. Further, cold offset is likely to occur, and gloss at the time of fixing is also low, which is not preferable. In order to keep these balances well, the melt index is preferably in the range of 5 to 30 g / 10 minutes, more preferably 7 to 20 g / 10 minutes. Therefore, when the melt index is within the range of the present invention, hot offset and cold offset are reduced, and even if an image is displayed for a long time, the image is not disturbed and good gloss can be obtained.

The melt index (MI (13
5 ° C., 2.16 kg)) is measured according to Japanese Industrial Standard Thermoplastic Flow Test Method JIS K721.
According to the description of No. 0, the measurement is performed by the manual cutting method under the following measurement conditions. At this time, the measured value is converted into a 10-minute value. Measurement temperature: 135 ° C. Load: 2.16 kg Sample filling amount: 5-10 g

The toner of the present invention has a gel content of 5 to 50%, preferably 7 to 35. If the gel content is less than 5%, wrapping around the fixing device or high-temperature offset may occur. Further, if the gel content is more than 50%, the fixing temperature becomes too high, so that the temperature inside the apparatus becomes too high due to the increase in the power consumption of the fixing device and the temperature rise inside the device, which may cause the toner deterioration in the toner container. There is. Further, cold offset is likely to occur, and gloss at the time of fixing is also low, which is not preferable.

As a method for measuring the gel content, 1 g of the sample toner or binder resin is weighed, and a cylindrical filter paper (for example, N
o. 86R size 28 × 100 mm (made by Toyo Roshi Kaisha, Ltd.) and put on a Soxhlet extractor. Next, 200 g of a tetrahydrofuran solvent is used for extraction for about 6 hours. At this time, the extraction cycle of the tetrahydrofuran solvent is about 4 to
Extraction is performed at a reflux rate of once every 5 minutes. After the extraction is completed, the cylindrical filter paper is taken out and weighed to obtain the insoluble content (gel content) of the toner or the binder resin in the tetrahydrofuran solvent in mass% based on the sample.

In the present invention, for any one kind of external additive, the volume average voltage of toner particles synchronized with the external additive is α, and the volume average voltage of toner particles not synchronized with the external additive is It is necessary that β / α when β is 0 to 1. When β / α is larger than 1, fusion with the electrostatic latent image carrier is likely to occur, which may cause deterioration in image quality when an image is displayed for a long period of time. And, more preferably, this value is ideally 0. Further, δ / γ, where γ is the count number of the toner particles synchronized with the external additive at the median voltage, and δ is the count number of the toner particles not synchronized with the external additive at the median voltage. Is 0
It is necessary to be 0.5, and if it is more than 0.5, fog or fusion to the electrostatic latent image carrier may occur. Further, it is preferably 0 to 0.3, and ideally 0.

The method of measuring the volume average voltage and the median voltage of the external additive and the toner particles in synchronism and non-synchronization are as a toner analysis method, the annual conference of the Institute of Electrophotography (total 95).
No.), "Japan Hardcopy '97", "New External Evaluation Method-Toner Analysis by Particle Analyzer", Toshiyuki Suzuki, Toshio Takahara, The Electrophotographic Society, July 9-11, 1997. Preferably, the toner analysis method described above is used.

In this toner analysis method, toner particles are introduced into plasma to excite the toner particles, and the emission spectrum associated with the excitation is detected to perform the analysis. According to this analysis method, it is possible to simultaneously detect the emission spectrum associated with the excitation of a plurality of elements, and it is also possible to measure the periodicity of the emission spectrum.

The elements contained in the same particle generate an excitation light emission spectrum (synchronous spectrum) at the same period, while the element existing as a simple substance like the external additive free material is not synchronized with the toner base. Produces an excitation emission spectrum (asynchronous spectrum) by itself. By relatively determining the non-synchronization / synchronization of the excitation and emission spectra derived from each of these elements, the volume average voltage with respect to the toner base at that time,
The median voltage was determined.

In the present application, the count (number) of emission spectra accompanying excitation of carbon atoms derived from the mother particles and the count (number) of emission spectra associated with excitation of Si atoms derived from silica such as silica as an external additive. Based on the synchronization difference, the toner particles in synchronization are made to be the toner particles to which the external additive is attached,
Asynchronous toner particles were used as toner particles to which no external additive was attached. Then, in each circle-equivalent diameter distribution, the number of counts at the volume average voltage and the median voltage is measured, and β /
α and δ / γ were obtained.

As a concrete measuring method, Yokogawa Electric Co., Ltd.
Using PT1000 manufactured by C, after measuring under the following conditions, C
The synchronism of the emission spectrum count of Si atoms based on the atoms was measured by applying the following equation.

<< Measurement conditions of PT1000 manufactured by Yokogawa Electric Co., Ltd. >> Number of C atoms detected in one measurement: 500 to 2500 Noise cut level: 1.5 or less Sort time: 20 digits Gas: O ₂ 0.1%, He gas-Analysis wavelength: C atom: 247.860 nm Si atom: 288.160 nm-Channel used: C atom: 1 or 2 Si atom: 1 or 2

Incidentally, the adjustment of β / α and δ / γ depends on the type of external additive to be used, the amount of external additive, the charging characteristics, hardness, cohesiveness, etc. of each external additive, so that various adjustments can be made. It is adjusted by the method, but in the present invention, it is adjusted by adding an external additive at the time of preparing the toner base material, and the order of external addition and the time of the external addition by dry external addition after the base material preparation, the external addition strength, and the sieving after the external addition. did.

The toner of the present invention defines the physical properties when left at 45 ° C. for 3 days. This is because it is an index that can be simply evaluated that the toner of the present invention can produce a good image without changing its characteristics even when a large amount of image is produced or a long-term storage is performed.

The toner of the present invention has a specific surface area ratio of 80 to 10 of that of the original toner when left at 45 ° C. for 3 days.
It is preferably 0%. If the ratio of the specific surface area after standing is less than 80%, embedding of the external additive easily occurs,
There is a possibility that the image quality may deteriorate when an image is displayed for a long time. In addition, it is usually difficult to think that more than 100%,
If it exceeds 100%, foaming, cracking / breaking of toner particles, separation of external additives, etc. may occur, so considering the possibility of such changes during toner storage, Not preferable.

The specific surface area was determined according to the BET method by using a specific surface area measuring device Autosorb 1 (manufactured by Yuasa Ionics Co., Ltd.) to adsorb nitrogen gas on the sample surface and calculating the specific surface area using the BET multipoint method.

About 10 days after the preparation, about 10 g of the toner was placed in a sample bottle, allowed to stand at 45 ° C. under normal pressure for 3 days, and then measured by the above method.

The average particle size and particle size distribution of the developer can be measured by various methods such as Coulter counter TA-II type or Coulter Multisizer (manufactured by Coulter). In the present invention, Coulter Multisizer (manufactured by Coulter) is used. ) Is used to connect an interface (manufactured by Nikkaki) and a PC9801 personal computer (manufactured by NEC) that output the number distribution and volume distribution, and the particle size range is 1
It was output as data divided into six. As the electrolytic solution, a 1% NaCl aqueous solution is prepared using primary sodium chloride. For example, ISOTON R-II (manufactured by Coulter Scientific Japan) can be used. As a measuring method, a surfactant, preferably 0.1 to 5 ml of alkylbenzene sulfonate is added as a dispersant to 100 to 150 ml of the electrolytic aqueous solution, and a measurement sample is further added to 2 to 20 m.
Add g. The electrolytic solution in which the sample is suspended is about 1 with an ultrasonic disperser.
The dispersion treatment was performed for up to 3 minutes, and the volume and number of toner particles having a particle size of 2 μm or more were measured by the Coulter Multisizer using a 100 μm aperture as an aperture to calculate a volume distribution and a number distribution.

In the present invention, the circularity is the equivalent circle diameter of the number of toner particles measured by a flow type particle image measuring device.
It is measured in a circularity scattergram, and in the present invention, it was measured using "FPIA-1000 type" (manufactured by Toa Medical Electronics Co., Ltd.) and calculated using the following formula. Circularity = circumference with the same projected area as the particle image / perimeter of the particle projected image

Here, the "particle projected area" is the area of the binarized toner particle image.

As a specific measuring method, 10 ml of ion-exchanged water from which impure solids and the like have been removed in advance is prepared in a container, and a surfactant, preferably an alkylbenzene sulfonate, is added as a dispersant into it. Then, 0.02 g of a measurement sample is further added and uniformly dispersed. As a means for dispersing, an ultrasonic disperser "UH-50 type" (manufactured by SMT) equipped with a titanium alloy chip of 5Φ as a vibrator was used, and dispersion treatment was performed for 5 minutes to obtain a dispersion liquid for measurement. To do. At that time, the dispersion is appropriately cooled so that the temperature of the dispersion does not exceed 40 ° C.

The flow type particle image measuring device was used for measuring the toner shape, and the toner particle concentration at the time of measurement was 3000.
The concentration of the dispersion liquid is readjusted to be about 10,000 particles / μl, and 1,000 or more toner particles are measured. After the measurement, this data is used to determine the average circularity of the toner.

In the toner particles used in the present invention, the average circularity is preferably in the range of 0.955 to 0.990.
When the average circularity is smaller than 0.950, the fluidity is deteriorated, and the toner deterioration is likely to occur when an image is displayed for a long time. If the average circularity is larger than 0.990, poor cleaning of undeveloped toner is likely to occur.

In the present invention, the glossiness representing the degree of gloss is defined by JIS Z 8741 (specular glossiness measuring method), J
Measured using a handy gloss meter PG-3D (manufactured by Nippon Denshoku Industries Co., Ltd.) under the conditions of an incident angle of light of 75 degrees, based on the regulations described in IS K 7105 (Plastic optical property test method). It is the value.

[0077]

EXAMPLES The present invention will be specifically described below with reference to Examples and Comparative Examples.

Example 1 First, a polymerized toner was prepared by the following procedure.

In 700 g of ion-exchanged water, 0.1 mol /
Add 500 g of Na ₃ PO ₄ aqueous solution at 50 ° C.
After heating to TK homomixer (made by Tokushu Kika Kogyo)
And was stirred at 10,000 rpm. 72 g of a 1.0 mol / liter CaCl ₂ aqueous solution was gradually added to this to obtain an aqueous medium containing Ca ₃ (PO ₄ ) ₂ .

The following formulation was heated to 60 ° C., and using a TK homomixer (made by Tokushu Kika Kogyo), 9,000 rpm
Were uniformly dissolved and dispersed. -Styrene 150 parts by mass-Methyl methacrylate 20 parts by mass-n-butyl acrylate 30 parts by mass-Carbon black 25 parts by mass-Aluminum salicylate compound 2 parts by mass-Saturated polyester 15 parts by mass-Stearyl stearate 28 parts by mass-Divinylbenzene 0 .6 parts by mass

Polymerization initiator 2,2'-azobis (2,4-dimethylvaleronitrile) (5 parts by mass) was dissolved therein to prepare a polymerizable monomer composition.

The above polymerizable monomer composition was charged into the above aqueous medium and stirred at 8,000 rpm at 60 ° C. in a nitrogen atmosphere using a TK homomixer to obtain the polymerizable monomer composition. Granulated.

Then, while stirring with a paddle stirring blade, the temperature was raised to 70 ° C. in 2 hours, and after 4 hours, the heating rate was 40 ° C./Hr.
The temperature was raised to 80 ° C. and the reaction was carried out for 5 hours. After completion of the polymerization reaction, the residual monomer was distilled off under reduced pressure, and after cooling, hydrochloric acid was added to dissolve the calcium phosphate salt and filtered, and 0.2 parts by mass of wet-process silica was dispersed in the aqueous phase during washing with water, The toner particles were aggregated and dried, and the particle size was adjusted by classification to obtain black toner base particles.

1.3 parts by mass of the external additive A was mixed with 100 parts by mass of the black toner base particles by a Henschel mixer (2000 rpm, 10 minutes), and the opening was 38 μm.
To obtain the toner of the present invention.

The weight average particle diameter of the toner was 6.7 μm, and the average circularity was 0.970.

The above toner was evaluated using a remodeling machine of a commercially available color laser printer LBP2160 (manufactured by Canon Inc.). The cyan cartridge of the above modified machine was filled with 300 g of toner, and a continuous printing test of 20,000 sheets was performed at a printing ratio of 1%. In each test, a solid black pattern and a solid white pattern were printed as samples at the initial and 20,000th sheets, and the images at that time were also confirmed.

With respect to each evaluation item, the suitable range for gloss is set to 5 to 70, and it is judged that the other ranges are not preferable. Further, regarding the offset, since it causes a decrease in gloss and a deterioration in image quality, it is not possible to cause both hot offset and cold offset.

Next, regarding the wrapping, an image is output by an LBP2160 machine in which the fixing device can be removed, and the degree of wrapping around the fixing roller is visually observed when an unfixed image is passed through the fixing device of the same machine. However, those that were wound around the fixing roller were evaluated as x, those that could be separated by the separation claws were evaluated as Δ, and those that were not wound were evaluated as o.

For long-term fog, images after continuous printing of 20,000 sheets were evaluated. If fog was less than 3%, it was good.
3% or more and less than 5% was acceptable, and 5% or more was not acceptable. By the way, the fog value was obtained by measuring the reflected light on a solid white image with a reflectometer (manufactured by Tokyo Denshoku Co., Ltd.). For long-term gloss, evaluate the images after continuous printing of 20,000 sheets, and if the difference in gloss value compared to the initial solid image is less than 5%, good, if 5% or more and less than 10%, acceptable, 10%
If it is above, it is judged as impossible.

Regarding the fusion, the images after continuous printing of 20,000 sheets are evaluated, and the number of print patterns by fusion per 10 cm ² is less than 1, good, and 1 or more and less than 3 is acceptable, 3
If more than one, it is not possible.

As described above, the list of external additives is shown in Table 1, the constitution and physical properties of the toner are shown in Table 2, and the evaluation results are shown in Table 3. Regarding the particle analyzer, C of toner particles and S of external additive are used.
Synchronous and asynchronous were measured for i.

Example 2 External additive B instead of external additive A
Evaluation was made in the same manner as in Example 1 except that was used. As described above, Table 1 shows the list of external additives, Table 2 shows the constitution and physical properties of the toner, and Table 3 shows the evaluation results.

Example 3 Evaluation was made in the same manner as in Example 1 except that 1.0 part by mass of the external additive A and 0.2 part by mass of the external additive C were used in place of the external additive A. did. As described above, Table 1 shows the list of external additives, Table 2 shows the constitution and physical properties of the toner, and Table 3 shows the evaluation results.

Example 4 Instead of the external additive A, the external additive A was used.
Evaluation was performed in the same manner as in Example 1 except that 1.0 part by mass and 0.2 part by mass of the external additive D were used. As described above, Table 1 shows the list of external additives, Table 2 shows the constitution and physical properties of the toner, and Table 3 shows the evaluation results.

[Example 5] External additive A instead of external additive A
Evaluation was performed in the same manner as in Example 1 except that 1.0 part by mass and 0.2 part by mass of the external additive E were used. As described above, Table 1 shows the list of external additives, Table 2 shows the constitution and physical properties of the toner, and Table 3 shows the evaluation results.

Example 6 Instead of the external additive A, the external additive A
Evaluation was performed in the same manner as in Example 1 except that 1.0 part by mass and 0.2 part by mass of the external additive F were used. As described above, Table 1 shows the list of external additives, Table 2 shows the constitution and physical properties of the toner, and Table 3 shows the evaluation results.

Example 7 Styrene-butyl acrylate copolymer 100 parts by mass Carbon black 7 parts by mass Behenyl behenate 10 parts by mass Aluminum salicylate compound 2 parts by mass After premixing the above materials, 130 ° C. Melt-kneading was carried out by the twin-screw kneading extruder set to. After cooling the kneaded product, it is roughly pulverized, finely pulverized by a pulverizer using a jet stream, further classified by an air classifier, and finally a hybridization system (Nara Kikai Seisakusho)
After adding 0.2 parts by mass of the external additive A to 8000 rp
Spheroidizing treatment was performed for 5 minutes. Evaluation was performed in the same manner as in Example 1 except that the toner base was used. The weight average particle diameter of the toner was 7.2 μm, and the average circularity was 0.938.

The external additives are listed in Table 1, the toner composition and physical properties are listed in Table 2, and the evaluation results are listed in Table 3.

Example 8 Evaluation was made in the same manner as in Example 7 except that the amount of the external additive A added was 5.3 parts by mass.

As described above, the list of external additives is shown in Table 1, the constitution and physical properties of the toner are shown in Table 2, and the evaluation results are shown in Table 3.

Example 9 Evaluation was carried out in the same manner as in Example 1 except that the amount of silica added during washing with water was set to 0.04 parts by mass, and thereafter no external addition was carried out.

As described above, Table 1 shows the list of external additives, Table 2 shows the constitution and physical properties of the toner, and Table 3 shows the evaluation results.

[Example 10] The external addition condition of the external additive A was set to 17
Evaluations were made in the same manner as in Example 1 except that the speed was set to 00 rpm for 5 minutes.

As described above, Table 1 shows a list of the external additives, Table 2 shows the constitution and physical properties of the toner, and Table 3 shows the evaluation results.

Example 11 The developer was evaluated in the same manner as in Example 1 except that the toner of Example 1 was prepared in a silicone resin-coated carrier so as to be 8% and evaluated by CLC1150.

As described above, Table 1 shows the list of external additives, Table 2 shows the constitution and physical properties of the toner, and Table 3 shows the evaluation results.

Example 12 Evaluation was made in the same manner as in Example 1 except that the external additive A was used as the external additive G.

As described above, a list of external additives is shown in Table 1, the constitution and physical properties of the toner are shown in Table 2, and the evaluation results are shown in Table 3.

Example 13 Styrene as a binder resin
Evaluation was performed in the same manner as in Example 1 except that a polyester resin (polycondensation polymer of propoxylated bisphenol and fumaric acid) was used instead of the acrylic resin.

As described above, Table 1 shows the list of external additives, Table 2 shows the constitution and physical properties of the toner, and Table 3 shows the evaluation results.

Example 14 Evaluation was made in the same manner as in Example 1 except that the following modified machine was used as the evaluation machine.

In the modified LBP2160, the cyan cartridge was modified as follows. The base layer of the toner carrier is N
A BR elastic roller is set so as to contact the latent image carrier during image formation, and is rotated at a peripheral speed 1.7 times the peripheral speed of the latent image carrier.

Further, a regulating member having a thin metal plate of phosphor bronze as a base is installed above the toner carrier, and the vicinity of the free end side tip is brought into surface contact with the outer peripheral surface of the toner carrier in the counter direction. It is provided so as to abut. The bias is a direct current voltage Vdc = -270V on the toner carrier.

The external additives are listed in Table 1, the toner composition and physical properties are listed in Table 2, and the evaluation results are listed in Table 3.

[Comparative Example 1] With a weight average particle diameter of 7.0 μm,
Evaluation was carried out in the same manner as in Example 1 except that 0.1 part by mass of toner base particles to which silica was not added at the time of washing with toner base water was added at the time of external addition.

As described above, Table 1 shows the list of external additives, Table 2 shows the constitution and physical properties of the toner, and Table 3 shows the evaluation results.

[Comparative Example 2] 3 parts of n-butyl acrylate were used.
Evaluation was carried out in the same manner as in Example 1 except that the amount of 5 parts by weight and the amount of methyl methacrylate used were 16 parts by weight.

The external additives are listed in Table 1, the toner composition and physical properties are listed in Table 2, and the evaluation results are listed in Table 3.

[Comparative Example 3] Two n-butyl acrylates were used.
Evaluation was carried out in the same manner as in Example 1 except that the amount of 4 parts by weight and the amount of methyl methacrylate used were 26 parts by weight.

As described above, the list of external additives is shown in Table 1, the constitution and physical properties of the toner are shown in Table 2, and the evaluation results are shown in Table 3.

[Comparative Example 4] Evaluation was made in the same manner as in Example 1 except that the amount of divinylbenzene was 0.6 part by mass.

As described above, Table 1 shows the list of external additives, Table 2 shows the constitution and physical properties of the toner, and Table 3 shows the evaluation results.

[Comparative Example 5] Evaluation was carried out in the same manner as in Example 1 except that divinylbenzene was not added.

The external additives are listed in Table 1, the toner composition and physical properties are listed in Table 2, and the evaluation results are listed in Table 3.

[Comparative Example 6] Evaluation was carried out in the same manner as in Example 1 except that 50 parts by mass of toner base particles to which silica was not added at the time of washing with water were used after the external addition was completed.

As described above, the list of external additives is shown in Table 1, the constitution and physical properties of the toner are shown in Table 2, and the evaluation results are shown in Table 3.

[0127]

[Table 1]

[0128]

[Table 2]

[0129]

[Table 3]

[0130]

According to the present invention, the gloss of the surface of a fixed image can be improved, and offset, winding around a fixing device, and fusion with an electrostatic latent image carrier can be prevented, and a good image quality can be obtained for a long time. A black toner that can be maintained can be provided.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Satoshi Handa             3-30-2 Shimomaruko, Ota-ku, Tokyo             Non non corporation (72) Inventor Yuji Moriki             3-30-2 Shimomaruko, Ota-ku, Tokyo             Non non corporation F-term (reference) 2H005 AA08 AA15 AA21 CA04 CB07                       CB10 CB13 EA01 EA03 EA07                       EA10 FA07

Claims (8)

[Claims] 1. A toner comprising at least a binder resin, a colorant and one or more external additives, wherein the toner has a melt index value of 5 to 30 and a gel content of 5 to 50%, In any one kind of external additive,
Β / α is 0 to 1, where α is the volume average voltage of the toner particles synchronized with the external additive and β is the volume average voltage of the toner particles not synchronized with the external additive. When the count number at the median voltage of the toner particles synchronized with the agent is γ and the count number at the median voltage of the toner particles not synchronized with the external additive is δ, δ / γ is 0 to 0. 5. A black toner used in a full-color machine characterized by being 5. 2. The toner has an average circularity of 0.955 to 5.
The black toner used in the full-color machine according to claim 1, having a value of 0.990. 3. The black used in the full color machine according to claim 1, wherein the ratio of the specific surface area of the toner when left at 45 ° C. for 3 days is 80 to 100% of the original toner. toner. 4. The black toner used in a full color machine according to claim 1, wherein the binder resin of the toner has a styrene-acrylic copolymer as a main component. 5. The black toner used in a full color machine according to claim 1, wherein at least one of the external additives is silica. 6. The toner base particles 10 are added in an amount of the external additive.
The black toner used in the full-color machine according to any one of claims 1 to 5, wherein the amount is 0.05 to 5.0 parts by mass per 0 parts by mass. 7. The black toner used in a full-color machine according to claim 1, wherein the toner is a non-magnetic single component. 8. The black toner used in a full-color machine according to claim 1, wherein at least one of the external additives contains Mg.