JP2851895B2 - Toner for developing electrostatic images - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a toner for visualizing a latent electrostatic image in an image forming method such as electrophotography and electrostatic recording.

[Conventional technology]

Conventionally, as electrophotography, U.S. Patent No. 2,297,691,
Various methods are described in JP-B-42-23910 and JP-B-43-24748.

Developing methods applied to the electrophotographic method and the like are roughly classified into a dry developing method and a wet developing method. The former is further classified into a method using a two-component developer and a method using a one-component developer.

Conventional toners applied to these dry development methods include:
A colored resin fine powder in which a dye or a pigment is dispersed in a natural or synthetic resin is used. For example, a colorant dispersed in a binder resin such as polystyrene is 1 to 30 μm
Finely pulverized particles are used as toner. As the magnetic toner, a toner containing magnetic particles such as magnetite is used. In the case of using a two-component developer, the toner is usually glass beads,
Used by mixing with carrier particles such as iron powder and ferrite particles.

Any toner must have a positive or negative charge, depending on the polarity of the electrostatic latent image to be developed.

In order to cause the toner to retain an electric charge, it is possible to use the frictional charging property of the resin which is a component of the toner.However, in this method, since the charging property of the toner is low, an image obtained by development is easily fogged and unclear. It will be. Therefore,
In order to impart an appropriate triboelectric charging property to a toner, a dye, a pigment, and a charge control agent for imparting charging property are added.

At present, as the charge control agents known in the art, metal complex salts of monoazo dyes, metal complex salts of salicylic acid, alkyl-substituted salicylic acid, naphthoic acid, dicarboxylic acid, copper phthalocyanine pigment and the like are known.

[Problems to be solved by the invention]

However, since some of these charge control agents easily contaminate the sleeve or the carrier, the toner using them tends to reduce the triboelectric charge amount as the number of copies increases, causing a decrease in the development density. . In addition, certain types of charge control agents have insufficient triboelectric charge and are susceptible to temperature and humidity, thus causing environmental fluctuations in image density. In addition, certain charge control agents have poor storage stability, and their triboelectric charging ability decreases during long-term storage. Further, since a certain type of charge control agent has poor dispersibility in a resin, the toner using the same has a non-uniform triboelectric charge amount between particles and is easily fogged. Further, certain charge control agents have poor thermal stability and may be decomposed and deteriorated during the heating and kneading process during toner production. A toner manufactured by reusing a part of a toner using such a charge control agent is liable to generate reversely chargeable particles and easily cause fogging. Some charge control agents are colored and cannot be used substantially in color toners.

At present, there is a strong demand for the development of charge control agents that satisfy all of these.

[Means and Actions for Solving the Problems] The present inventors have conducted intensive studies to achieve the above object, and as a result, the present invention was constituted only by repetition of a partial structural formula represented by the following formula (I), and was insoluble in tetrahydrofuran. The p-phenylphenol-aldehyde condensates have sufficient triboelectricity and at the same time are colorless or substantially colorless; when incorporated in a toner, the toner has a sufficient triboelectric charge; The inventors have found that the above problems can be solved, and have reached the present invention. Formula (I) Wherein R ₁ represents hydrogen or a methyl group, and R ₂ and R ₃ are
Each independently represents hydrogen, an alkyl group having 1 to 6 carbon atoms,
Halogen, carboxyl group, hydroxy group, cyano group,
Nitro group, methyl halide group, trimethylsilyl group,
Examples thereof include an ester group having 1 to 8 carbon atoms, an amide group having 1 to 8 carbon atoms, an acyl group having 1 to 12 carbon atoms, a sulfonyl group having 1 to 8 carbon atoms, and an ether group having 1 to 8 carbon atoms. The present invention relates to a toner composed of only the repetition of the partial structural formula represented by the above (I) and containing p-phenylphenol-aldehyde condensates insoluble in tetrahydrofuran as a negatively chargeable charge control agent.

As an example in which a phenol type compound is used as a charge control agent, a low molecular weight resin containing an amino group and a phenol group is proposed in JP-A-63-138355-138357.
However, these resins are contained in the toner for the purpose of imparting positive chargeability, and have different purposes and characteristics from the present invention.

Also, JP-A-63-260253 and JP-A-63-266462
In the publication, a phenol compound is proposed as a toner composition. However, when these phenolic compounds were examined, it was found that these phenolic compounds themselves have low negative triboelectric chargeability and, when used as a charge control agent, are limited by resins and other toner materials. .

JP-B-58-9415 and JP-A-63-260253 propose a polycondensate of a phenol compound and an aldehyde or ketone or a phenol resin as a toner composition for controlling a negative charge. . However, these polycondensates or phenolic resins have a melting point or softening point at 200 ° C. or lower, and thus have a negative triboelectric charging property when incorporated in a toner, but have the following problems.

1. Many of them have insufficient negative triboelectrification properties and must be added in large amounts to toner.

2. The amount of the additive significantly changes the fixing characteristics of the toner.

3. Due to decomposition and deterioration during heating and kneading in the toner production process, the toner characteristics greatly depend on the production conditions.

4. Toner produced by reusing fine powder toner produced during production is liable to fog. Further, the polycondensates or phenolic resins shown therein are characterized in that they are soluble in solvents.

A monomer serving as a raw material for the p-phenylphenol-aldehyde condensates insoluble in tetrahydrofuran of the present invention,
For example, p-phenylphenol itself has low charge-imparting ability. However, the present inventors have determined that the monomer is not a p-phenylphenol resin which can be dissolved in a solvent, but a p-phenylphenol-aldehyde condensate insoluble in tetrahydrofuran, by a condensation reaction with aldehydes. Have high negative frictional charge and solve the above problems.

Although the reason why the p-phenylphenol-aldehyde condensate insoluble in tetrahydrofuran has a high triboelectric charge amount is unknown, the soluble p-phenylphenol resin has a simple chain structure, It is presumed that the p-phenylphenol-aldehyde condensate insoluble in tetrahydrofuran has a preferable property as a charge control agent because the phenyl group portion of the substituent is crosslinked and has a three-dimensional crosslinked structure. Is done.

The p-phenylphenol-aldehyde condensates which are composed only of the repetition of the partial structural formula represented by the formula (I) and are insoluble in tetrahydrofuran have no melting point or softening point at 250 ° C. or lower and are deteriorated. There are features in difficult places. Therefore, as compared with general polycondensates and phenolic resins, there is no effect on the fixing characteristics of the toner. Also,
Even during heating and kneading, there is little degradation and alteration,
There is an advantage that the charging characteristics of the toner do not depend much on the manufacturing conditions, and fogging does not occur even in a toner manufactured by reusing fine powder toner.

Further, it is composed only of the repetition of the partial structural formula represented by the formula (I) of the present invention, and is insoluble in p-tetrahydrofuran.
In phenylphenol-aldehyde condensates,
It is characterized by having a phenyl group on the phenol skeleton. In the case of a conventionally known phenol resin, the charge control agent has insufficient triboelectric charging ability, whereas the phenol resin is constituted only by repeating the partial structural formula represented by the general formula (I) of the present invention. , P insoluble in tetrahydrofuran
-Phenylphenol-aldehyde condensates have high triboelectric charging ability. This is considered to be due to the electron withdrawing property of the phenyl group. Furthermore, p-phenylphenol-aldehyde condensates insoluble in tetrahydrofuran having an electron-withdrawing group in the phenyl group tend to have a higher triboelectric charge.

Also, because the dispersibility of the binder resin has been improved,
The frictional charging between the toner particles became uniform, the generation of the oppositely charged particles was suppressed, and no fogging occurred. Further, contamination of the toner carrier such as a sleeve and a carrier can be reduced, and an image of good image quality can be obtained even when the toner is stored for a long time under high temperature and high humidity. Further, the dependence of the image on the environment is reduced, and an image having a sufficient density can be obtained under high temperature and high humidity conditions or low temperature and low humidity conditions.

As described above, p-phenylphenol-aldehyde condensates insoluble in tetrahydrofuran, which are constituted only by repeating the partial structural formula represented by the formula (I) of the present invention, tend to have a higher triboelectric charge.

Further, the compound of the present invention is composed only of the repetition of the partial structural formula represented by the formula (I), and is insoluble in tetrahydrofuran.
-Phenylphenol-aldehyde condensates show an absorption band due to stretching vibration of a hydroxyl group of 3170 in an IR spectrum.
Have in the range of ~ 3300cm ^-1 . The position of this absorption band indicates that the hydroxyl group forms a relatively strong hydrogen bond. If the absorption band is higher than this, the charge amount tends to be low.

It is appropriate that the IR spectrum is measured by a KBr method using a measuring instrument using a Fourier transform method.

The p-phenylphenol-aldehyde condensates, which are constituted only by repeating the partial structural formula represented by the formula (I) of the present invention and are insoluble in tetrahydrofuran, are partially converted into the formula (I) by heating to a high temperature. Decomposes into decomposition products corresponding to the partial structural formula shown by This decomposed product can be confirmed by a mass spectrum, and a fragment corresponding to the partial structural formula represented by the formula (I) or a fragment of a multimeric product thereof can be detected by a mass spectrum.

In order to measure a mass spectrum, a direct introduction method is preferable.

The p-phenylphenol-aldehyde condensates which are constituted only by repeating the partial structural formula represented by the formula (I) of the present invention and are insoluble in tetrahydrofuran can be obtained by a known method using the corresponding phenol compound and aldehyde. Can be synthesized.

The p-phenylphenol-aldehyde condensate insoluble in tetrahydrofuran of the present invention is obtained by converting p-phenylphenol and an aldehyde or an aldehyde equivalent such as paraformaldehyde in an organic solvent using a strong base as a catalyst in a range of 50 to 200. It can be obtained by heating to ° C. In addition, a substituent is introduced into an intermediate product soluble in an organic solvent obtained from p-phenylphenol and an aldehyde according to the above synthesis method, and an aldehyde and a strong base catalyst are added, followed by condensation. Can also be obtained.

For example, in the case of a condensate of p-phenylphenol and paraformaldehyde, p-phenylphenol and excess paraformaldehyde are mixed with xylene as a solvent and potassium hydroxide as a catalyst, and the mixture is mixed at 60 ° C. for 6 hours. It can be obtained by heating and stirring and then heating and stirring at 140 ° C. for 10 hours.

In the case of a condensate having bromine as a substituent, p-
Phenylphenol and formaldehyde are mixed in a xylene solvent, and potassium hydroxide is used as a catalyst at 100 ° C. for 6 hours.
By heating and stirring for a period of time, a soluble p-phenylphenol condensate was obtained, which was subsequently reacted with bromine in a tetrahydrofuran solvent, and further reacted with formaldehyde in a xylene solvent using potassium hydroxide as a catalyst.
By reacting at 0 ° C., an insoluble condensate can be obtained.

Specific examples of the p-phenylphenol-aldehyde condensates that can be used in the present invention are shown below, but these are representative examples in consideration of ease of handling and the like, and do not limit the compounds of the present invention in any way. .

Compound Examples (1) A condensate obtained by reacting p-phenylphenol and paraformaldehyde with xylene as a solvent and potassium hydroxide as a catalyst.

(2) A condensate obtained by reacting p- (4-bromophenyl) phenol with paraformaldehyde using xylene as a solvent and potassium hydroxide as a catalyst.

(3) p-phenylphenol and formaldehyde are mixed in a xylene solvent and reacted with potassium hydroxide as a catalyst to obtain a soluble p-phenylphenol condensate;
A condensate obtained by successively reacting this with bromine in a tetrahydrofuran solvent and further reacting this with formaldehyde in a xylene solvent using potassium hydroxide as a catalyst.

(4) A condensate obtained by reacting biphenyl-4,4'-diol with paraformaldehyde using xylene as a solvent and potassium hydroxide as a catalyst.

(5) A condensate obtained by reacting p- (4-chlorophenyl) phenol, paraformaldehyde and xylene with a solvent and potassium hydroxide as a catalyst.

(6) A condensate obtained by reacting p- (4-ethylphenyl) phenol with paraformaldehyde using xylene as a solvent and sodium hydroxide as a catalyst.

(7) A condensate obtained by reacting p- (4 trimethylsilylphenyl) phenol with paraformaldehyde using xylene as a solvent and potassium hydroxide as a catalyst.

(8) A condensate obtained by reacting p-phenylphenol and paraformaldehyde with xylene as a solvent and sodium hydroxide as a catalyst.

(9) A condensate obtained by reacting p-phenylphenol and paraformaldehyde with xylene as a solvent and rubidium hydroxide as a catalyst.

In the present invention, as a method of incorporating the p-phenylphenol-aldehyde condensate into the toner, there are a method of adding the toner to the inside of the toner and a method of externally adding the toner. The amounts of these compounds used are determined by the type of the binder resin, the presence or absence of additives used as necessary, and the toner production method including the dispersion method, and are not specifically limited. However, when internally added, it is preferably used in an amount of 0.1 to 10 parts by weight, more preferably 0.1 to 5 parts by weight, based on 100 parts by weight of the binder resin. When adding externally, use resin 100
It is preferably 0.01 to 10 parts by weight based on parts by weight.

In the case of external addition, it is particularly preferable to fix or bury the particles near the surface of the fine particles made of the binder resin and the colorant by mechanical impact.

First, as a pretreatment, while dispersing the charge control agent (particles (B)), the particles are rubbed with the colored fine particles (particles (A)) and adhere to the colored fine particles by electrostatic force and Van der Waals force. Generally, a mixer with a high-speed stirring blade is used, but any mixer having a mixing function and a dispersing function may be used. Further, a pulverizer, a vibration mill or the like may be used with a reduced impact force. In order to make the pretreatment dispersion more uniform, a fluidity-imparting agent, a lubricant, a conductivity-imparting agent, or the like may be added as a dispersing aid, if necessary.

Further, the p-phenylphenol-aldehyde condensate of the present invention may be used in combination with a conventionally known charge control agent such as an alkyl salicylic acid complex salt, a metal complex salt of a monoazo dye, a boron compound, and a sulfonic acid pendant resin. it can.

In the toner of the present invention, a silica fine powder can be externally added to the toner. As the silica fine powder, silica fine powder produced by a dry method and a wet method can be used.

The dry method referred to here is a method for producing silica fine powder generated by vapor phase oxidation of a silicon halide. For example, in a method utilizing the thermal decomposition oxidation reaction of silicon tetrachloride gas in oxygen-hydrogen, the basic reaction formula is as follows.

SiCl ₄ + 2H ₂ + O ₂ → SiO ₂ + 4HCl In this production process, for example, another metal halide such as aluminum chloride or titanium chloride is used together with a silicon halide to produce a composite fine powder of silica and other metal oxides. It is also possible to obtain and include them.

On the other hand, as a method for producing the silica fine powder used in the present invention by a wet method, various conventionally known methods can be applied. For example, degradation by acid silicon sodium, if Shimese the general reaction scheme (hereinafter Scheme is _{omitted), Na 2 O · XSiO 2} + HCl + H 2 O → SiO 2 · nH 2 O + NaCl Besides, ammonia salts or alkali salts of sodium silicate , An alkaline earth metal silicate is produced from sodium silicate, then decomposed with acid to form silicic acid, a sodium silicate solution is converted to silicic acid with ion exchange resin, natural silicic acid or silicic acid There is a method using an acid salt.

Silica such as aluminum silicate, sodium silicate, potassium silicate, magnesium silicate, zinc citrate, etc. can be applied to the silica fine powder here.

Among the above-mentioned silica fine powders, those having a specific surface area of 30 m ² / g or more (particularly 50 to 400 m ² / g) by nitrogen adsorption measured by the BET method are preferable.

Further, the silica fine powder used in the present invention may be treated with a silane coupling agent, if necessary, with a treating agent such as an organosilicon compound for the purpose of hydrophobization, and a known method is also used. Then, it is treated with the treating agent which reacts or physically adsorbs with the silica fine powder. Such treating agents include, for example, hexamethyldisilazane, trimethylsilane, trimethylchlorosilane, trimethylethoxysilane, dimethyldichlorosilane, methyltrichlorosilane, allyldimethylchlorosilane, allylphenyldichlorosilane, benzyldimethylchloro Silane, bromomethyldimethylchlorosilane, α-chloroethyltrichlorosilane, β-chloroethyltrichlorosilane, chloromethyldimethylchlorosilane, triorganosilylmercaptan, trimethylsilylmercaptan, triorganosilyl acrylate, vinyldimethylacetoxysilane, dimethylethoxysilane, Dimethyldimethoxysilane, diphenyldiethoxysilane, hexamethyldisiloxane, 1,3-divinyltetramethyldisiloxane, 1,3
Diphenyltetramethyldisiloxane, and dimethylpolysiloxane having from 2 to 12 siloxane units per molecule and having terminal hydroxyl units each containing one hydroxyl group bonded to Si. These are one or two
Used in mixtures of more than one species.

Finally, the degree of hydrophobicity of the treated silica fine powder was determined as a degree of hydrophobicity measured by a methanol titration test, 30
It is preferred that the developer containing such silica fine powder exhibits a triboelectric charge amount which is sharp and uniform and exhibits a negative chargeability when hydrophobicized so as to show a value within the range of -80. Here, in the methanol titration test, the degree of hydrophobicity of the silica fine powder having a hydrophobicized surface is confirmed.

The "methanol titration test" defined herein for evaluating the degree of hydrophobicity of the treated silica fine powder is performed as follows. 0.2 g of the test silica fine powder is added to 50 ml of water in a 250 ml Erlenmeyer flask. Methanol is titrated from the vial until all of the silica has been wetted.
At this time, the solution in the flask is constantly stirred with a magnetic stirrer. The end point is observed as the entire amount of fine silica powder is suspended in the liquid, and the degree of hydrophobicity is expressed as the percentage of methanol in the liquid mixture of methanol and water when the end point is reached.

Examples of the coloring agent used in the present invention include carbon black, lamp black, iron black, ultramarine blue, nigrosine dye, aniline blue, phthalocyanine blue, phthalocyanine green, Hansa Yellow G, rhodamine 6G, coco oil blue, chrome yellow, quinacridone, Conventionally known dyes and pigments such as benzidine yellow, rose bengal, triarylmethane dyes, monoazo and disazo dyes can be used alone or in combination.

The resin used in the present invention includes, for example, styrene such as polystyrene, poly-p-chlorostyrene, and polyvinyl toluene, and a homopolymer of a substituted product thereof;
p-chlorostyrene copolymer, styrene, -vinyltoluene copolymer, styrene-vinylnaphthalene copolymer,
Styrene-acrylic acid ester copolymer, styrene-methacrylic acid ester copolymer, styrene-α-chloromethyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-vinyl methyl ether copolymer, styrene-vinylethyl Styrene copolymers such as ether copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile-indene copolymer; polyvinyl chloride, phenol resin , Natural modified phenolic resin, natural resin modified maleic resin, acrylic resin, methacrylic resin, polyvinyl acetate, silicone resin, polyester resin, polyurethane, polyamide resin, furan resin, epoxy resin, xylene resin, polyvinyl butyral Terpene resins, Kumaroinden resins, and petroleum resins.

Further, a crosslinked styrene copolymer is also a preferable binder resin.

Examples of the comonomer for the styrene monomer of the styrene copolymer include acrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate, dodecyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, phenyl acrylate, and methacrylic acid. Monocarboxylic acid having a double bond such as acid, methyl methacrylate, ethyl methacrylate, butyl methacrylate, octyl methacrylate, acrylonitrile, methacrylonitrile, acrylamide or a substituted product thereof; for example, maleic acid, butyl maleate Dicarboxylic acids having a double bond, such as methyl, methyl maleate, dimethyl maleate, and the like; and vinyl chloride, vinyl acetate,
Vinyl esters such as vinyl benzoate; ethylene-based olefins such as ethylene, propylene, butylene; vinyl ketones such as vinyl methyl ketone and vinyl hexyl ketone; vinyl methyl ether, vinyl ethyl ether; Vinyl monomers such as vinyl isobutyl ether and the like; vinyl monomers such as alone or two or more are used.

Here, as the cross-linking agent, a compound having two or more polymerizable double bonds is mainly used, and examples thereof include aromatic divinyl compounds such as divinylbenzene and divinylnaphthalene; for example, ethylene glycol diacrylate and ethylene glycol diacrylate. Carboxylic acid esters having two double bonds such as methacrylate and 1,3-butanediol dimethacrylate; divinyl compounds such as divinylaniline, divinylether, divinylsulfide and divinylsulfone; and three or more vinyl groups Is used alone or as a mixture.

When a pressure fixing method is used, a binder resin for a pressure fixing toner can be used. For example, polyethylene, polypropylene, polymethylene, polyurethane elastomer, ethylene-ethyl acrylate copolymer, ethylene-vinyl acetate copolymer can be used. Coalescent, ionomer resin, styrene-butadiene copolymer, styrene-isoprene copolymer, linear saturated polyester, paraffin and the like.

Further, the toner for electrostatic charge development of the present invention may contain a magnetic material and be used as a magnetic toner. Examples of the magnetic material used include iron oxides such as magnetite, γ-iron oxide, ferrite, and iron-rich ferrite; metals such as iron, cobalt, and nickel; or these metals and aluminum, cobalt, copper, lead, magnesium, and tin. And alloys with metals such as zinc, antimony, beryllium, bismuth, cadmium, calcium, manganese, selenium, titanium, tungsten, and vanadium, and mixtures thereof. These magnetic materials preferably have an average particle size of 0.1 to 1 μm, preferably about 0.1 to 0.5 μm, and the amount contained in the magnetic toner is 40 to 150 parts by weight per 100 parts by weight of the binder resin component. Preferably it is 60 to 120 parts by weight.

In the magnetic toner using the charge control agent of the present invention,
A toner having a volume average particle diameter of 3 to 15 μm can be used;
In particular, 12 to 60 magnetic toner particles having a particle size of 5 μm or less
1 to 33% by number of magnetic toner particles having a particle size of 8 to 12.7 μm, 2.0% by volume or less of magnetic toner particles having a particle size of 16 μm or more, and a volume average particle size of the magnetic toner. The diameter is more preferably 4 to 10 μm from the viewpoint of developing characteristics.

The particle size distribution of the toner can be measured by various methods, but in the present invention, it is appropriate to use a Coulter counter.

In other words, the Coulter Counter TA is used as a measuring device.
-Interface (made by Nikkaki) that outputs number distribution and volume distribution using Model II (manufactured by Coulter) and CΧ-1
A personal computer (manufactured by Canon Inc.) is connected, and the electrolyte is adjusted to about 1% NaCl aqueous solution using primary sodium chloride. For example, ISOTON-II (manufactured by Coulter Science Japan) can be used. As a measuring method, a surfactant, preferably an alkylbenzene sulfonate, is used as a dispersant in 100 to 150 ml of the electrolytic aqueous solution.
Add 5 ml, and then add 2-20 mg of the measurement sample. The electrolyte solution in which the sample was suspended was subjected to a dispersion treatment for about 1 to 3 minutes with an ultrasonic disperser, and the above Coulter Counter TA-II was used.
Using a 100 μm aperture as the aperture, the particle size distribution of the particles of 2 to 40 μm based on the number is measured and converted to determine the particle size distribution of the toner.

Further, the toner of the present invention can be used as a two-component toner by mixing with a carrier. As the carrier that can be used in the present invention, known carriers can be used, for example, iron powder, ferrite powder, magnetic powder such as nickel powder, glass beads, and the like, and the surface thereof is treated with a resin or the like. What is done is raised. Examples of the resin for coating the carrier surface include styrene-acrylate copolymer, styrene-methacrylate copolymer, acrylate copolymer, methacrylate copolymer, silicone resin, and fluorine-containing resin. , A polyamide resin, an ionomer resin, a polyphenylene sulfide resin, or a mixture thereof.

The toner of the present invention may optionally contain additives. Examples of the additive include a lubricant such as zinc stearate; an abrasive such as cerium oxide and silicon carbide; a fluidity imparting agent such as aluminum oxide; an anti-caking agent; and a carbon black and tin oxide. There is a conductivity imparting agent.

Further, a fluorine-containing polymer fine powder such as a polyvinylidene fluoride fine powder is also a preferable additive from the viewpoint of fluidity, abrasiveness, charge stability and the like.

In addition, wax-like substances such as low-molecular-weight polyethylene, low-molecular-weight polypropylene, microcrystalline wax, carnauba wax, sasol wax, and paraffin wax are used for the purpose of improving the releasability at the time of hot roll fixing.
Addition of about 5% by weight to the toner is also a preferred embodiment of the present invention.

In producing the toner according to the present invention, after sufficiently mixing the toner constituent materials as described above with a ball mill or other mixer, kneading well using a hot roll kneader or a heat kneader of an extruder, After cooling and solidifying, it is preferable to obtain the toner by mechanical pulverization and classification. Another method is to obtain a toner by dispersing the constituent materials in a binder resin solution and then spray-drying; or, in a so-called microcapsule toner composed of a core material and a shell material, a core material or a shell material, A method of including a predetermined material in both of them can be applied.

Further, a polymerization toner production method in which a predetermined material is mixed with a monomer to form a binder resin to form an emulsified suspension and then polymerized to obtain a toner can be applied.

Further, if necessary, desired additives are sufficiently mixed by a mixer such as a Hensiel mixer, and the toner according to the present invention can be manufactured.

The toner of the present invention can be used for development for visualizing an electrostatic image in electrophotography, electrostatic recording, electrostatic printing, and the like, by a conventionally known means.

The p-phenylphenol-aldehyde condensates of the present invention are colorless or pale in color and have good triboelectrification.

Therefore, the toner of the present invention hardly causes image quality deterioration due to continuous copying and can provide an image having excellent density uniformity.

〔Example〕

Hereinafter, the present invention will be described specifically with reference to Examples, but the present invention is not limited thereto. All parts in the following formulations are parts by weight.

Example 1 After the above materials were mixed well in a blender, they were kneaded with a biaxial kneading extruder set at 150 ° C. The obtained kneaded material was cooled, coarsely pulverized by a cutter mill, and then finely pulverized using a fine pulverizer using a jet stream, and the obtained finely pulverized powder was classified by a fixed wall type air classifier.

Further, the obtained classified powder is strictly classified and removed simultaneously by a multi-division classifier using a Coanda effect (an elbow jet classifier manufactured by Nippon Steel Mining Co., Ltd.), and the volume average particle size is 8.5 μm.
m was obtained. What was classified and removed in this process is referred to as fine powder A.

Silica fine powder (BET specific surface area: 300 m ² / g) obtained by hydrophobizing 100 parts of the obtained fine powder with hexamethyldisilazane
0.6 part was added and mixed with a Hensiel mixer to obtain a toner to which silica fine powder was externally added.

Next, 5.5 parts of the obtained toner was mixed with 100 parts of an acrylic-coated ferrite carrier having an average particle diameter of 65 μm to prepare a developer.

This developer was used in a commercially available color electrophotographic copying machine CLC-1.
(Manufactured by Canon Inc.).

As a result, under an environmental condition of 23 ° C./60%, a bright black image having an image density of 1.44 was obtained from the beginning, and deterioration after 10,000 copies was not recognized.

Next, when a copy test was performed under an environmental condition of 15 ° C./10%, an image having a high density of 1.43 was obtained from the beginning. In addition, 32
A good image having a density of 1.46 was obtained even under the environmental conditions of ° C / 85%.

Example 2 A fine powder having a volume average particle size of 8.1 μm was obtained in the same manner as in Example 1 except that 5 parts of the carbon black in Example 1 was changed to 4 parts of a copper phthalocyanine pigment (CI Pigment Blue 15), and silica was further mixed. To obtain a toner.

Next, the same carrier as in Example 1 was mixed at the same ratio to obtain a developer.

This developer was subjected to a copy test in the same manner as in Example 1. As a result, under the environmental conditions of 23 ° C / 60%,
A good blue image without fog having a density of 1.43 was obtained. 1
No deterioration in image quality was observed even after copying 10,000 sheets.

A copy test was performed under environmental conditions of 35 ° C./85% and 15 ° C./10%, and good results were obtained as in the case of 23 ° C./60%.

Example 3 A fine powder having a volume average particle diameter of 8.0 μm was obtained in the same manner as in Example 1 except that 5 parts of the carbon black in Example 1 was changed to 4 parts of a quinacridone pigment (CI Pigment Red 122). To obtain a toner.

Next, the same carrier as in Example 1 was mixed at the same ratio to obtain a developer.

This developer was subjected to a copy test in the same manner as in Example 1. As a result, under the environmental conditions of 23 ° C / 60%,
A good magenta image with a fog density of 1.45 was obtained. No deterioration in image quality was observed even after copying 10,000 sheets.

A copy test was performed under environmental conditions of 35 ° C./85% and 15 ° C./10%, and good results were obtained as in the case of 23 ° C./60%.

Example 4 A fine powder having a volume average particle diameter of 8.0 μm was obtained in the same manner as in Example 1 except that 5 parts of the carbon black in Example 1 was changed to 5 parts of a yellow pigment (CI Pigment Yellow 17). A toner was obtained.

Next, the same carrier as in Example 1 was mixed at a ratio of 6 parts of the toner to 100 parts of the carrier to obtain a developer.

This developer was subjected to a copy test in the same manner as in Example 1. As a result, under the environmental conditions of 23 ° C / 60%,
A good yellow image having a density of 1.44 without fog was obtained. 1
No deterioration in image quality was observed even after copying 10,000 sheets.

A copy test was performed under environmental conditions of 35 ° C./85% and 15 ° C./10%, and good results were obtained as in the case of 23 ° C./60%.

Example 5 Black, cyan, magenta, and black used in Examples 1 to 4
Where a full-color image was obtained using a yellow developer,
A vivid full-color image with excellent color mixing and gradation was obtained.

Example 6 The above material was treated in the same manner as in Example 1 to obtain a volume average particle size of 8.3 μm.
m, and the same silica as in Example 1 was mixed in the same amount to obtain a toner.

Next, the same evaluation as in Example 1 was carried out by mixing 5.5 parts of the toner obtained with 100 parts of an acrylic coated ferrite carrier having an average particle diameter of 65 μm to obtain a developer.

As a result, a clear and high-density image was obtained from the beginning under each environmental condition, and an image of good image quality was obtained even in a 10,000-sheet copy test.

Comparative Example 1 Example 1 was repeated except that 2.5 parts of the compound example (1) in Example 1 was replaced with 7 parts of p-phenylphenol resin (pp-811, manufactured by Gunei Chemical Industry Co., Ltd.) soluble in tetrahydrofuran. A fine powder having a volume average particle size of 8.3 μm was obtained in the same manner as described above, and the same silica was mixed at the same ratio to obtain a toner. What was classified and removed in this process is referred to as fine powder B.

Next, the fine powder B was reused as a toner raw material in the same manner as in Example 6, and the compound example (1) in Example 6 was used.
5 parts, a fine powder having a volume average particle diameter of 8.7 μm was obtained in the same manner as in Example 6, except that 20 parts of the fine powder A were changed to 7 parts of p-phenylphenol resin soluble in tetrahydrofuran and 20 parts of the fine powder B. The same silica was mixed in the same amount to obtain a toner.

Next, 5 parts of the obtained toner were mixed with 100 parts of an acrylic-coated ferrite carrier having an average particle diameter of 65 μm to prepare a developer, and the same evaluation as in Example 1 was performed.

As a result, under an environmental condition of 23 ° C./60%, an image having a sufficient image density of 1.40 was initially obtained, but as the copying test was continued, the image became fogged.
After 5,000 copies, the fog became severe and had a quality that would pose a practical problem.

Example 7 After the above materials were mixed well in a blender, they were kneaded with a twin screw extruder set at 140 ° C. The obtained kneaded material was cooled, coarsely pulverized by a cutter mill, and then finely pulverized using a fine pulverizer using a jet stream, and the obtained finely pulverized powder was classified by a fixed wall type air classifier.

Further, the obtained fine powder was strictly classified and removed simultaneously by a multi-division classifier utilizing a Coanda effect (an elbow jet classifier manufactured by Nippon Steel Mining Co., Ltd.), and the volume average particle diameter was 8.6μ.
m was obtained.

Silica fine powder (BET specific surface area: 300 m ² / g) obtained by hydrophobizing 100 parts of the obtained fine powder with hexamesyldisilazane
0.6 part was added and mixed with a Hensiel mixer to obtain a magnetic toner.

This toner was applied to a commercially available copier (trade name: NP-6650, manufactured by Canon Inc.) and subjected to a copy test at 23 ° C./60% under environmental conditions. As a result, the image density was 1.34, and there was no fog or dust. A clear image with a resolution of 6.3 lines / mm was obtained. Further, when the durability performance was examined by continuously copying 30,000 sheets, a good image comparable to the initial image was obtained with an image density of 1.32 and a resolution of 6.3 lines / mm. Further, when the triboelectric charge amount of the toner on the developing sleeve was measured, it was -11.2 μc / g at the initial stage, and was -10.7 μc / g after 30,000 copies, and almost no sleeve contamination was observed.

Next, when a copy test was conducted under an environmental condition of 15 ° C./10%, an image of high density and good image quality was obtained. 3
The results were similarly good in the continuous copying test of 10,000 copies.

When the same copy test and continuous copy test were performed under the environmental conditions of 35 ° C./85%, good results were obtained. Further, after the toner was allowed to stand for one month under these environmental conditions, the same copying test and continuous copying test were performed. The results were satisfactory without any problem.

Example 8 After the above materials were mixed well in a blender, they were kneaded with a twin screw extruder set at 140 ° C. The obtained kneaded material was cooled, coarsely pulverized by a cutter mill, and then finely pulverized using a fine pulverizer using a jet stream, and the obtained finely pulverized powder was classified by a fixed wall type air classifier.

Further, the obtained fine powder was strictly classified and removed simultaneously by a multi-division classifier using a Coanda effect (Elbojet Classifier manufactured by Nippon Steel Mining Co., Ltd.), and the volume average particle diameter was 11.8μ.
m was obtained.

Silica fine powder (BET specific surface area 200 m ² / g) obtained by hydrophobizing 100 parts of the obtained fine powder with dimethyldichlorosilane.
4 parts were added and mixed with a Hensiel mixer to obtain a toner.

Next, 10 parts of the obtained toner were mixed with 100 parts of an acrylic-coated ferrite carrier having an average particle diameter of 65 μm to prepare a developer.

When this developer was applied to a commercially available copying machine (trade name: NP-6650, manufactured by Canon Inc.) and subjected to a copy test at 23 ° C./60% environmental conditions, an image with good image quality of 1.31 was obtained. Was done. Using the above-mentioned developer, 3000 sheets were continuously copied, and the durability performance was examined. As a result, a good image comparable to the initial image was obtained.

Next, a copy test was performed under environmental conditions of 15 ° C./10% and 35 ° C./83%, and similarly good results were obtained.

Example 9 After the above materials were mixed well in a blender, they were kneaded with a biaxial kneading extruder set at 150 ° C. The obtained kneaded material was cooled, coarsely pulverized by a cutter mill, and then finely pulverized using a fine pulverizer using a jet stream, and the obtained finely pulverized powder was classified by a fixed wall type air classifier.

Further, the obtained classified powder is strictly classified and removed simultaneously by a multi-division classifier using a Coanda effect (an elbow jet classifier manufactured by Nippon Steel Mining Co., Ltd.), and the volume average particle size is 8.5 μm.
m was obtained.

Silica fine powder (BET specific surface area: 300 m ^{2 /} g) 0.6 obtained by hydrophobizing 100 parts of the obtained fine powder with hexamesyldisilazane
Was added and mixed with a Hensiel mixer to obtain a toner.

Next, 5.5 parts of the obtained toner was mixed with 100 parts of an acrylic-coated ferrite carrier having an average particle diameter of 65 μm to prepare a developer.

This developer was used in a commercially available color electrophotographic copying machine CLC-1.
(Manufactured by Canon Inc.).

As a result, under an environmental condition of 23 ° C./60%, a vivid black image having an image density of 1.40 was obtained from the beginning, and no deterioration was observed after copying 10,000 sheets.

Next, when a copy test was performed under an environmental condition of 15 ° C./10%, an image with a high density of 1.35 was obtained from the beginning. In addition, 32
A good image having a density of 1.41 was obtained even under environmental conditions of ° C / 85%.

Example 10 After the above materials were mixed well in a blender, they were kneaded with a biaxial kneading extruder set at 150 ° C. The obtained kneaded material was cooled, coarsely pulverized by a cutter mill, and then finely pulverized using a fine pulverizer using a jet stream, and the obtained finely pulverized powder was classified by a fixed wall type air classifier.

Further, the obtained fine powder was strictly classified and removed simultaneously by a multi-division classifier using a Coanda effect (Elbojet Classifier manufactured by Nippon Steel Mining Co., Ltd.), and the volume average particle diameter was 11.8μ.
m was obtained.

To 100 parts of this fine powder, 1.0 part of Compound Example (5) and 0.4 part of silica fine powder were mixed with a Hensiel mixer to perform pretreatment.

Next, processing was performed using the apparatus shown in FIG. 1 under the conditions of a minimum gap of 1 mm, a peripheral speed of the blade of 60 m / sec, and a processing time of 5 minutes. When the processed product was observed with an electron microscope, it was observed that the processed product was partially fixed and embedded on the toner surface. The fixation ratio was measured to be 90%. Further, a toner was obtained in which 0.6 part of silica fine powder (BET specific surface area: 300 m ^{2 /} g) hydrophobized with hexamethyldisilazane was added to 100 parts of the processed product.

This toner was applied to a commercially available copying machine (trade name: NP-6650, manufactured by Canon Inc.) and subjected to a copying test under an environment of 23 ° C./60%. A clear image was obtained. Further, when 10,000 sheets were continuously copied, the durability performance was examined. As a result, an image having an image density of 1.30 and a good image comparable to the initial image were obtained.

Next, when a copy test was conducted under an environmental condition of 15 ° C./10%, an image of high density and good image quality was obtained. 1
The results were similarly good in the continuous copying test of 10,000 copies.

Further, when the same copy test and continuous copy test were performed under the environmental conditions of 35 ° C./85%, good results were obtained.

Example 11 0.5 g of γ-aminopropyltrimethoxysilane was added to 1200 ml of ion-exchanged water, and 10 g of Aerosil 200 (Nippon Aerosil) was further added. The mixture was heated to 70 ° C., and a TK homomixer M type (manufactured by Tokushu Kika Kogyo Kogyo) ) And dispersed at 10,000 rpm for 15 minutes. Further, 19 g of N / 10HCl was added to adjust the pH in the system to 6.

The components of the above formulation were heated to 70 ° C. in a container, and dissolved and dispersed at 10,000 rpm for 5 minutes using a TK homomixer M type to obtain a monomer mixture. While maintaining the temperature at 70 ° C., 10 parts of an initiator V-601 (manufactured by Wako Pure Chemical Industries, Ltd.) was added and dissolved to prepare a monomer composition.

Into the two flasks containing the dispersion medium obtained above, the monomer composition was charged, and the mixture was stirred at 10,000 rpm for 60 minutes using a TK homomixer at 70 ° C. under a nitrogen atmosphere. The product was granulated. Then, while stirring with the paddle stirring blade,
Polymerization was performed at 70 ° C. for 10 hours. After the completion of the polymerization reaction, the reaction product was cooled, NaOH was added to dissolve the dispersant, and the mixture was filtered, washed with water, and dried to obtain a polymerized toner. The particle size of the obtained toner was 8.5 μm.

When this toner was applied to a commercially available copying machine (trade name: NP-6650, manufactured by Canon Inc.) and subjected to a copying test under an environment of 23 ° C./60%, the image density was 1.32, and there was no fog or dust. A clear image was obtained. Furthermore, when the durability performance was examined by continuously copying 5,000 sheets, an image having an image density of 1.30 and a good image comparable to the initial image were obtained.

Next, when a copy test was performed under environmental conditions of 15 ° C./10% and 35 ° C./85%, a high-density and good-quality image was similarly obtained. The results were similarly good in the 5,000-sheet continuous copy test.

〔The invention's effect〕

As described above, the toner containing the p-phenylphenol-aldehyde condensate of the present invention as a charge control agent has a sufficient triboelectric charge amount, has a uniform triboelectric charge amount between toner particles, and has no fog. Gives good images. Since the contamination of the toner carrier such as the sleeve and the carrier by the charge control agent has been reduced, an image having a sufficient density can be obtained even after a large number of copies, and the density is stable.
Further, since the image density has little dependence on temperature and humidity, an image of excellent quality can be provided under a wide range of environmental conditions. In addition, since it does not easily change over time, it has excellent quality stability during storage. Further, since the toner is not decomposed and deteriorated at the time of heating and kneading, waste toner generated at the time of toner production can be reused, and resource saving can be achieved.

Further, since the color tone disturbance due to the charge control agent is small, it can be used for a color toner.

[Brief description of the drawings]

FIG. 1 is an explanatory view schematically showing an example of an apparatus for fixing and embedding particles (B) on particles (A). DESCRIPTION OF SYMBOLS 1 ... Rotating shaft 2 ... Rotor 3 ... Dispersion blade 4 ... Rotating piece (blade) 5 ... Partition disk 6 ... Casing 7 ... Liner 8 ... Impact part 9 ... Inlet chamber 10 ... Outlet Chamber 11 Return path 12 Product take-out unit 13 Raw material input valve 14 Blower 15 Jacket

Claims (1)

(57) [Claims] (1) The following formula (I) (Wherein, R ₁ represents hydrogen or a methyl group, and R ₂ and R ₃ are
Each independently represents hydrogen, an alkyl group having 1 to 6 carbon atoms,
Halogen, carboxyl group, hydroxy group, cyano group,
Nitro group, methyl halide group, trimethylsilyl group,
It represents an ester group having 1 to 8 carbon atoms, an amide group having 1 to 8 carbon atoms, an acyl group having 1 to 12 carbon atoms, a sulfonyl group having 1 to 8 carbon atoms, or an ether group having 1 to 8 carbon atoms. A toner for developing an electrostatic image, comprising at least one kind of p-phenylphenol-aldehyde condensates insoluble in tetrahydrofuran, which is constituted only by repeating the partial structural formula represented by the formula: