JPH049861A - Nonmagnetic toner - Google Patents

Abstract

PURPOSE:To obtain bright images free from fogging, spots, stains, etc., without generating filming on a photosensitive body by incorporating fine silicic acid powder which is synthesized by a wet process, has a specific bulk density and is treated with a silane coupling agent and/or silicone oil into the above toner. CONSTITUTION:The fine silicic acid powder which is synthesized by the wet process, has 30 to 60g/l bulk density and is treated with the silane coupling agent and/or the silicone oil is incorporated into this toner. The flocs of the primary particles of the fine silicic acid powder in the nonmagnetic toner and the lumps formed by the additional flocculation of the flocs are not admitted and the fine silicic acid powder disperses and sticks uniformly and strongly to the surfaces of the toner particles in the case of the nonmagnetic toners formed by incorporating the fine silicic acid powder having 30 to 60g/l bulk density into the part near the toner surfaces. The generation of the filming on the photosensitive body is obviated even if the toner is used for image formation over a long period of time. The bright images free from the fogging, dots and stains are thus obtd. over a long period of time.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a developer for developing latent images in electrophotography, electrostatic recording, electrostatic printing, magnetic recording, and the like. More specifically, the present invention relates to a non-magnetic toner for electrophotography that is uniformly positively charged, visualizes a negative electrostatic charge image, and provides a high-quality image in a direct or indirect electrophotographic development method.

[Prior art] As a conventional electrophotographic method, U.S. Patent No. 2,297,691
Although a number of methods are known, such as those described in the specification of No. After the toner image is transferred to a transfer material such as paper as necessary, it is fixed by heat, pressure, solvent vapor, etc. to obtain a copy. Furthermore, when a process for transferring a toner image is included, a process for removing residual developer on the photoreceptor is usually provided.

Development methods for visualizing electrical latent images using toner include, for example, the magnetic brush method described in U.S. Pat. No. 2,874,063, and the cascade method described in U.S. Pat. Development method and 2.221, 7
Powder cloud method described in US Pat. No. 76, U.S. Pat.
, 909,258, which uses conductive magnetic toner, is known.

As toners applied to these developing methods, fine powders in which dyes and pigments are dispersed in natural or synthetic resins have conventionally been used. For example, particles obtained by dispersing a colorant in a binder resin such as polystyrene and pulverizing the particles to about 1 to 30 μm are used as toner. In the case of a system using a two-component developer, a non-magnetic toner is usually mixed with carrier particles such as glass beads or iron powder.

Conventionally, toner particles (the toner before adding fine silicic acid powder is hereinafter referred to as toner particles) are given sufficient triboelectric charge, and at the same time, the transfer efficiency is increased and the fluidity is improved.
In order to prevent the toner bridging phenomenon in the developing device and to ensure smooth toner supply during development, it is possible to add silicic acid fine powder produced by a dry method or wet method to toner particles by dry mixing. Are known. However, since the silicic acid fine powder itself is wood-philic, it deteriorates the environmental characteristics of the developer, causing significant fogging on the white background especially under high temperature and high humidity conditions, making it unusable.

Therefore, in order to overcome this drawback, it has been proposed to make silicic acid fine powder hydrophobic by surface treatment.
There are 16219 Publication 1 and JP-A-58-186751 Publication. In this regard, non-magnetic toners containing hydrophobic fine silicic acid powder obtained by surface treating fine silicic acid powder with various coupling agents have been proposed. Further, for the purpose of further hydrophobicizing silicic acid fine powder and controlling the chargeability, Japanese Patent Application Laid-Open No. 58-60754 and Japanese Patent Application Laid-open No. 59-201
In JP-A No. 063, a non-magnetic toner containing fine silicic acid powder surface-treated with various silicone oils or modified silicone oils was proposed, and in JP-A No. 59-45457, proposed a non-magnetic toner containing fine silicic acid powder treated with a silane coupling agent and silicone oil.

However, these surface-treated silicic acid fine powders
When a conventional general dry mixer is used for long-term image printing durability using non-magnetic toner contained near the surface of toner particles, fine silicic acid powder adheres and accumulates on the photoreceptor, causing film damage. It has been found that fogging, spots, and spots are likely to occur on images.

An example of a scanning electron micrograph showing the silicic acid fine powder adhering to the photoreceptor and causing filming is shown in the first image.
As shown in the figure.

There are various possible causes of this filming, but as a result of research on the above-mentioned development, the present inventor found that the main cause was a problem with the dispersion and adhesion of the silicic acid fine powder in the toner. This will be explained below.

First, these surface-treated wet-process synthetic silicic acid fine powders have a primary particle diameter of about 3 to 50 mμ, but the state of the silicic acid fine powders before dry mixing with toner particles is It exists as aggregates (approximately 1.5 to 50 μ) and clumps (approximately 30 to 300 μ) in which aggregates are further aggregated.

Scanning electron micrographs of surface-treated wet-synthesized silicic acid fine powder are shown in FIGS. 2 and 3.

The silicic acid fine powder must strongly adhere to the vicinity of the toner surface while removing aggregates of primary particles and clumps of aggregates by dry mixing with the toner particles. However, as a dry mixing method, simple addition or mixing using a stirring blade or the like in a mixer such as a Henschel mixer or Birbenmeyer at a circumferential speed of several m/sec to about 40 m/sec is generally used.

However, in this method, there is a large difference in circumferential speed between the vicinity of the rotating shaft in the center and the tip of the stirring blade, and since there is no blade-shaped part in the rotating shaft, the stirring force and dispersion force are limited. This tends to result in non-uniform dispersion. Therefore, in such dry mixing, aggregates of the primary particles of the silicic acid fine powder and lumps of aggregates are difficult to separate and remain in the non-magnetic toner as they are; The silicic acid fine powder also has weak adhesion to the surface of the non-magnetic toner and is easily separated. As a result, when a large number of copies are made using the non-magnetic toner, aggregates of primary particles of silicic acid fine powder remaining in the non-magnetic toner, clumps of aggregates, and clumps from the surface of the non-magnetic toner are found. The separated silicic acid fine powder adheres and accumulates on the surface of the photoreceptor, making it easy for filming to occur.

In particular, silicic acid fine powder whose surface has been treated with a silicone oil system has a strong cohesive force between primary particles and between aggregates, so that filming tends to occur easily.

As mentioned above, FIG. 4 shows a scanning electron micrograph of the non-magnetic toner in which the fine silicic acid powder is poorly dispersed.

In addition, in recent years, as image forming apparatuses such as electrophotographic copying machines have become widespread, their uses have expanded to a wide variety of uses, and demands on their image quality have become stricter. Therefore, JP-A-58
Japanese Patent Publication No. 129437 attempts to provide a non-magnetic toner having a special particle size distribution and a volume average particle size smaller than that of conventional developers, thereby achieving high image quality of copied images and the like. However, when using a non-magnetic toner obtained by dry mixing silicic acid fine powder with toner particles having a relatively smaller particle size than conventional toner particles, the contact area on the photoreceptor increases. However, there is a problem in that the silicic acid fine powder is more likely to adhere to the photoreceptor, and filming is more likely to occur.

Furthermore, non-magnetic toner visualizes electrostatic charge images, but as an electrophotographic photoreceptor that retains electrostatic charge images, organic toners with excellent low cost, light weight, high productivity, and film forming properties are preferred. Photoconductive photoreceptors are widely used. However, since organic photoconductive photoreceptors have a lower surface hardness than inorganic photoreceptors, aggregates of primary particles of silicic acid fine powder in non-magnetic toner and lumps of aggregates may cause the photoreceptor to There is a problem that the surface is easily damaged, and the uneven portions are prone to adhesion and accumulation of silicic acid fine powder, which tends to cause filming.

[Problems to be Solved by the Invention] An object of the present invention is to provide a non-magnetic toner that solves the above-mentioned problems.

A further object of the present invention is to prevent fogging, spots, and
It is an object of the present invention to provide a non-magnetic toner that can provide clear images without stains or the like.

A further object of the present invention is to provide a nonmagnetic toner that does not cause filming on a photoreceptor, has high image density, and has excellent fine line reproducibility and gradation.

A further object of the present invention is to provide a nonmagnetic toner that does not cause filming on a photoconductor even when an organic photoconductive photoconductor is used as an electrostatic latent image carrier.

[Means and effects for solving the problems] The present invention has a bulk density of 30 to 60 g/j! The present invention relates to a non-magnetic toner characterized by containing a silane coupling agent or a wet-process synthetic silicic acid fine powder treated with a silicone oil.

As a result of extensive research, the present inventors have found that by reducing aggregates of primary particles of wet-synthesized silicic acid fine powder treated with a silane coupling agent or silicone oil, and by reducing lumps formed by further agglomeration of aggregates, Considering that the bulk density of the silicic acid fine powder decreases, it is further confirmed that the bulk density is 30 to 60 g/
The silicic acid fine powder of R is mixed with a conventional general dry mixer,
In the non-magnetic toner contained near the toner surface, no aggregates of primary particles of the silicic acid fine powder in the non-magnetic toner and no lumps formed by further agglomeration of the aggregates were observed, and furthermore, no clumps of the silicic acid fine powder were observed. It has been found that the particles adhere uniformly and strongly to the surface of the toner particles. As a result, the non-magnetic toner has excellent filming resistance because the wet-process synthetic fine silicic acid powder in the non-magnetic toner does not adhere or accumulate on the photoreceptor even after long-term image printing durability. It demonstrates this.

However, since the primary particles of fine silicic acid powder synthesized by the wet method (compared to those produced by the dry method) originally have a strong cohesive force, it is difficult to completely hydrophobize the primary particles even if hydrophobization treatment is performed. be.

Therefore, it is not preferable to excessively reduce aggregates of primary particles of the hydrophobized fine silicic acid powder and lumps formed by further aggregation of the aggregates, and the bulk density of the fine silicic acid powder is 3.
0g#! If it is less than this, the environmental characteristics of the non-magnetic toner will deteriorate, and a foggy image with different distillation will be likely to occur, especially under high temperature and high humidity conditions.

In the present invention, the bulk density of the wet-synthesized silicic acid fine powder treated with a silane coupling agent or silicone oil is a value determined as follows. That is, the inner diameter is 2.
52cm, height 5.00cm capacity 1, OOcm
' Place the cylindrical container on a horizontal surface, and
The bulk density is calculated from the weight of the sample in the container by gently dropping the sample from above to fill the container, removing the excess that rose above the horizontal surface of the opening, and calculating the bulk density.

In the present invention, the method for obtaining a wet-process synthetic silicic acid fine powder treated with a silane coupling agent or silicone oil having a bulk density of 30 to 60 g/R includes, for example,
The surface-treated wet-method synthesized silicic acid fine powder is subjected to an impact-type ultrafine pulverizer, Costomizer (manufactured by Nara Kikai Seisakusho Co., Ltd.).
There is a method of crushing aggregates of primary particles of the silicic acid fine powder and clumps of aggregates. In addition, as another method, for example, an unsurface-treated wet-process synthetic silicic acid fine powder is brought into contact with a silane coupling agent or silicone oil, and at the same time, it is pulverized using the above-mentioned surface-connected ultrafine pulverizer. By doing so, it is possible to obtain fine silicic acid powder having a bulk density of 30 to 60 g/ρ and surface-treated with the treatment agent.

FIG. 5 shows a scanning electron micrograph of the surface-treated wet-method-synthesized silicic acid fine powder shown in FIGS. 2 and 3, which has been pulverized using a costomizer. Further, FIG. 6 shows an example of the relationship between the bulk density of the surface-treated wet-process synthetic silicic acid fine powder and the crushing time in a costomizer.

The bulk density obtained as described above is 30 to 60 g/f! The surface-treated wet-method synthesized silicic acid fine powder can be strongly adhered to the vicinity of the surface of the toner particles together with the toner particles by general dry mixing. Bulk density is 30-60g/R
A scanning electron micrograph is shown in FIG. 7 as an example of a non-magnetic toner obtained by mixing the surface-treated wet-process synthetic silicic acid fine powder with a toner in a Henschel mixer.

In addition, for the purpose of achieving high image quality of copied images, etc., toner particles with a smaller volume average particle diameter and a special particle size distribution than conventional toner particles are used to produce toner particles with a small bulk density obtained as described above. Even when surface-treated wet-process synthetic silicic acid fine powder is dry-blended, the filming resistance of the obtained non-magnetic toner on the photoreceptor is not reduced.

For example, for the purpose of achieving high image quality of copied images, etc.
12 to 60% by number of toner particles having a particle size of 8 to 12.7 μm are contained, 1 to 33% by number of toner particles having a particle size of 8 to 12.7 μm are contained, and toner particles having a particle size of 16 μm or more are contained. , the surface-treated wet process synthetic silicone having a bulk density of 30 to 60 g/l is added to toner particles having a particle size distribution of 4 to 10 tLm and having a volume particle size of 4 to 10 tLm. Although the non-magnetic toner obtained by dry mixing acid fine powder has a large contact area with the photoreceptor, the silicic acid fine powder in the non-magnetic toner does not adhere or deposit on the photoreceptor. It maintains excellent filming resistance.

In addition, in a non-magnetic toner containing the surface-treated wet-process synthetic silicic acid fine powder having a bulk density of 30 to Bog/R, aggregates of primary particles of the wet-process synthetic silicic acid fine powder are contained in the non-magnetic toner. Since there are very few lumps of aggregates and agglomerates, the surface of the photoreceptor will not be damaged, and the uneven parts will prevent the adhesion and accumulation of wet-process synthesized silicic acid fine powder, thereby preventing filming. .

In addition, the non-magnetic toner containing the surface-treated wet-process synthetic silicic acid fine powder with a bulk density of 30 to 80 g# does not deteriorate the environmental characteristics and has stable fogging even under high temperatures. Not maintain a clear image.

In the present invention, the bulk density is 30~aog,'f! A wet method synthetic silicic acid fine powder treated with a silane coupling agent or a silicone oil is used, but various conventionally known methods can be used to produce the silicic acid fine powder by a wet method. . For example, the general reaction formula for the decomposition of sodium silicate with an acid is shown below.

Na2(lXsi02+)ICIl+H20-5iO2
-nH20+NaCJ! Other methods include decomposition of sodium silicate with ammonia salts or alkali salts, generation of alkaline earth metal silicate from sodium silicate, decomposition with acid to produce silicic acid, and method of decomposing sodium silicate solution with ion exchange resin. There are methods such as using silicic acid, and using natural silicic acid or silicate.

As the silicic acid fine powder referred to herein, any of anhydrous silicon dioxide (silica) and other silicates such as aluminum silicate, sodium silicate, potassium silicate, magnesium silicate, and zinc silicate can be used.

Commercially available fine silicic acid powder synthesized by a wet method includes, for example, those sold under the following trade names.

Carplex Shionogi Nip Seal Nippon Silica Toraseal. Fine Seal Tokuyama Sodavita Seal Multi-wooden Hijiruton, Silnetx Mizusawa Kagaku Stahi Mesa Ishi Runruloid Kamishima Chemical Ehime Pharmaceutical Fuji Davison Chemical (Illinois Minerals) Calcium 5ilikat (calcium silicate lease) Sil moss white masonry
Among the silicic acid fine powders synthesized by the wet method above, the specific surface area due to nitrogen adsorption measured by the BET method is 3 am2/g or more (particularly 5 am2/g or more).
0 to 4 oom'/g) gives good results.

Furthermore, in the present invention, the wet-process-synthesized silicic acid fine powder is surface-treated with a silane coupling agent or silicone oil, and used in a state of reaction or physical adsorption with these treatment agents.

In the present invention, the silane coupling agent also includes organosilicon compounds, such as hexamethyldisilazane, vinyltriethoxysilane, vinyltrimethoxysilane, trimethylsilane, trimethylchlorosilane, trimethylethoxysilane, dimethyldichlorosilane, methyl Trichlorosilane, allyldimethylchlorosilane, allyl phenyldichlorosilane, benzyldimethylchlorosilane,
Bromomethyldimethylchlorosilane, α-chloroethyltrichlorosilane, β-chloroethyltrichlorosilane, chloromethyldimethylchlorosilane, triorganosilylmercaptan, trimethylsilylmercaptan, triorganosilylacrylate, vinylmethylacetoxysilane, dimethylethoxysilane, dimethyldimethoxy Silane, diphenyljethoxysilane, hexamethyldisiloxane, 1,3-divinyltetramethyldisiloxane, 1,3-diphenyltetramethyldisiloxane,
and dimethylpolysiloxane, which has 2 to 12 siloxane units per molecule, and each unit located at the end contains one hydroxyl group bonded to Si.

Further, in the present invention, the silane coupling agent may be a nitrogen-containing silane coupling agent, and has, for example, a structure generally represented by the following formula.

R, -5i-Yn (R represents an alkoxy group or a halogen, Y represents an amino group or an organo group having at least one nitrogen atom, m and n are integers of 1 to 3, and rn+n
=4. ) Examples of the organo group having at least one nitrogen atom include an amino group having an organic group as a substituent, a nitrogen-containing heterocyclic group, or a group having a nitrogen-containing heterocyclic group. Examples of the nitrogen-containing heterocyclic group include unsaturated heterocyclic groups and saturated heterocyclic groups, and publicly known ones can be used. Examples of the unsaturated heterocyclic group include the following.

Examples of the saturated heterocyclic group include the following.

The heterocyclic group used in the present invention is preferably a five-membered ring or a six-membered ring in consideration of stability.

Examples of such treatment agents include aminopropyltrimethoxysilane, aminopropyltriethoxysilane, dimethylaminopropyltrimethoxysilane, diethylaminopropyltrimethoxysilane, dipropylaminopropyltrimethoxysilane, dibutylaminopropyltrimethoxysilane, Monobutylaminopropyltrimethoxysilane, dioctylaminopropyltrimethoxysilane, dibutylaminopropylmethoxysilane, dibutylaminopropylmonomethoxysilane, dimethylaminophenyltriethoxysilane, trimethoxysilyl-γ-
There are propylphenylamine, trimethoxysilyl-γ-propylbenzylamine, etc. Furthermore, as the nitrogen-containing composite element environment, those with the above-mentioned structure can be used. Examples of such compounds include trimethoxysilyl-γ-propyl Examples include piperidine, trimethoxysilyl-γ-propylmorpholine, trimethoxysilyl-γ-propylimidazole, and the like.

In the present invention, the silicone oil is generally represented by the following formula.

Preferred silicone oils include those having a viscosity of approximately 5 to 500 centistokes at 25°C, such as methyl silicone oil.

Preferred are dimethyl silicone oil, phenylmethyl silicone oil, chlorphenylmethyl silicone oil, alkyl-modified silicone oil, fatty acid-modified silicone oil, polyoxyalkyl-modified silicone oil, and the like.

Further, in the present invention, the silicone oil may be a modified silicone oil having an organo group having at least one nitrogen atom in its side chain, for example, a silicone oil having at least a partial structure represented by the following formula can be used.

(In the formula, R1 represents hydrogen, an alkyl group, an aryl group, or an alkoxy group, R2 represents an alkylene group or a phenylene group, R3 and R4 represent hydrogen, an alkyl group, or an aryl group, and R5 represents a nitrogen-containing heterocyclic ring. The above alkyl group, aryl group, alkylene group, and phenylene group may have an organo group having a nitrogen atom, or may have a substituent such as a halogen.

In the present invention, these silane coupling agents and silicone oils may be used alone or in a mixture of two or more.

In the present invention, the application amount of wet-process synthetic silicic acid fine powder having a bulk density of 30 to 60 g/l and treated with these silane coupling agents or silicone oil is as follows:
0.00 parts by weight of the silicic acid fine powder per 100 parts by weight of toner particles.
0.01 to 8 parts by weight, preferably 0.1 to 5 parts by weight.

The binder resin used in the non-magnetic toner of the present invention includes:
When using a heating and pressure roller fixing device having an oil coating device, the following toner binder resins can be used.

For example, monopolymers of styrene and its substituted products such as polystyrene, poly-p-chlorostyrene, and polyvinyltoluene; styrene-p-chlorostyrene copolymers, styrene-vinyltoluene copolymers, styrene-vinylnaphthalene copolymers , styrene-acrylic acid ester copolymer, styrene-methacrylic acid ester copolymer, styrene-α-methyl chloromethacrylate copolymer, styrene-
Acrylonitrile copolymer, styrene-vinyl methyl ether copolymer, styrene-vinyl ethyl ether copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile- Styrenic copolymers such as indene copolymers; polyvinyl chloride, phenolic resin, naturally modified phenolic resin, natural resin-modified maleic acid resin, acrylic resin, methacrylic resin, polyvinyl acetate, silicone resin, polynystyl resin, polyurethane, polyamide Resin, furan resin, epoxy resin, xylene resin, polyvinyl butyral, terpene resin, coumaron indene resin, petroleum resin, etc. can be used.

In the heating and pressure roller fixing method that does not apply much oil, the so-called offset phenomenon, in which a part of the toner image on the toner image support member is transferred to the roller, and the adhesion of the toner to the toner image support member are important issues. be. Toners that are fixed with less thermal energy usually tend to block or cake during storage or in a developing device, so these problems must also be taken into consideration. The physical properties of the binder resin in the toner are most significantly involved in these phenomena. Therefore, when using the heated pressure roller fixing method in which little oil is applied in the present invention, the selection of the binder resin is more important. Preferred binding materials include crosslinked styrenic copolymers or crosslinked polyesters.

Examples of comonomers for the styrene monomer in the styrenic copolymer include acrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate, dodecyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, phenyl acrylate, and methacrylate. acids, monocarboxylic acids having a double bond such as methyl methacrylate, ethyl methacrylate, butyl methacrylate, octyl methacrylate, acrylonitrile, methacrinitrile, acrylamide, etc., or substituted products thereof; for example, maleic acid, butyl maleate, Dicarboxylic acids with double bonds such as methyl maleate, dimethyl maleate, etc.; vinyl esters, such as vinyl chloride, vinyl acetate, vinyl benzoate, etc.; e.g., ethylene, propylene, butylene, etc. Ethylene olefins: Vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone, etc.; Vinyl ethers such as vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether; Two or more are used.

As the crosslinking agent, compounds having two or more polymerizable double bonds are mainly used, such as aromatic divinyl compounds such as divinylbenzene and divinylnaphthalene; for example, ethylene glycol diacrylate,
Carboxylic acid esters having two double bonds such as ethylene glycol dimethacrylate and 1,3-butanediol dimethacrylate; divinyl compounds such as divinylaniline, divinyl ether, divinyl sulfide, and divinyl sulfone; and three or more vinyl Compounds having groups can be used alone or as a mixture.

In addition, when using a pressure fixing method, it is possible to use a binder resin for pressure fixing toner, such as polyethylene,
Examples include polypropylene, polymethylene, polyurethane elastomer, ethylene-dityl acrylate copolymer, ethylene-vinyl acetate copolymer, ionomer resin, styrene-butadiene copolymer, styrene-isoprene copolymer, linear saturated polyester, and paraffin.

Further, in the non-magnetic toner of the present invention, it is preferable that a charge control agent is added to the toner particles (internally added) or mixed with the toner particles (externally added).

As a positive charge control agent, nitributylbenzylammonium-1-, a modified product of nigrosine and fatty acid metal salts, etc.
Quaternary ammonium salts such as hydroxy-4-naphthosulfonate, tetrabutylammonium tetrafluoroborate; diorganotin oxides such as dibutyltin oxide, dioctyltin oxide, dicyclohexyltin oxide; dibutyltinborate, dioctyltinforate, dicyclohexyl Diorgano tin borates such as tin borates can be used alone or in combination of two or more. Among these, charge control agents such as nigrosine and quaternary ammonium salts are particularly preferably used.

In addition, a monopolymer of 1,000 yen expressed by the general formula % formula %) R2, R1 substituted or unsubstituted alkyl group (preferably 01 to C4) or styrene, acrylic ester, methacrylic acid as described above Copolymers with polymerizable polymers such as esters can be used as positive charge control agents, in which case these charge control agents also act as (all or part of) the binder resin. have

The above-mentioned charge control agent (one that does not function as a binder resin) is preferably used in the form of fine particles. In this case, the number average particle size of this charge control agent is specifically:
The thickness is preferably 4 μm or less (more preferably 3 μm or less).

When internally added to the toner, such a charge control agent is added in an amount of 0.1 to 20 parts by weight (or even 0,
2 to 10 parts by weight] The non-magnetic toner of the present invention, which is preferably used, may have various additives added internally or externally as necessary.

As the coloring agent, conventionally known dyes and pigments can be used, and usually 0.5 parts by weight per 100 parts by weight of the binder resin.
~20 parts by weight may be used. Other additives include, for example, lubricants such as zinc stearate, abrasives such as cerium oxide, silicon carbide, resin particles, flow agents such as aluminum oxide, anti-caking agents, or carbon black, oxidized There are conductivity imparting agents such as tin.

In addition, in order to improve the mold releasability during hot roll fixing, waxy substances such as low molecular weight polyethylene, low molecular weight polypropylene, microcrystalline wax, carnauba wax, Sasol wax, paraffin fuchs, etc.
It is also one of the preferred embodiments of the present invention to add about 5 wt% to the developer.

Examples of the carrier used in the present invention include magnetic powders such as iron powder, ferrite powder, and nickel powder, glass beads, etc., and their surfaces coated with resins (e.g., fluororesin, silicone resin, styrene-acrylic resin). Examples include those processed with etc.

It is preferable to use 10 to 1000 parts by weight (preferably 30 to 500 parts by weight) of carrier for 10 parts by weight of toner. The particle size of the carrier is preferably 30 to 10 μm (preferably 35 to 80 μm) for matching with the toner in the present invention.

The non-magnetic toner of the present invention is produced by mixing vinyl and non-vinyl thermoplastic resins, pigments or dyes as colorants, charge control agents, other additives, etc. in a mixing machine such as a ball mill. The coloring agent,
Dispersing or dissolving a charge control agent and other additives, 6
After assimilation, crushing and classification, the bulk density is 30~
60g #! The non-magnetic toner according to the present invention is prepared by externally adding and mixing a silane coupling agent or a silicone oil-treated wet-process synthetic silicon 1llI fine powder and, if necessary, other external additives. You can get it.

When using the non-magnetic toner of the present invention, photoreceptors include cadmium sulfide, selenium, and zinc oxide.

Organic photoconductor (OPC), amorphous silicon (α
-51) etc. are used.

When using the non-magnetic toner of the present invention, methods for cleaning residual toner etc. on the photoconductor include blade cleaning method, fur brush cleaning method, lif cleaning method, etc.
! Although a dry brush cleaning method or the like may be used, in the present invention, a blade cleaning method is preferred in view of the excellent combination of the non-magnetic toner and the photoreceptor of the present invention. Further, immediately before the cleaning process, a static elimination process or the like may be provided as necessary to facilitate toner cleaning.

[Example] The method of the present invention will be specifically described below based on Examples. However, this does not limit the embodiments of the present invention in any way. All parts in the examples are parts by weight.

Example 1 The above materials were thoroughly mixed in a blender, and then kneaded in a twin-screw kneading extruder set at 150°C.

The obtained kneaded material was cooled and coarsely pulverized using a cutter mill, and then finely pulverized using a pulverizer using a jet stream.
The obtained finely pulverized powder was classified using a fixed wall type wind classifier to produce classified powder. Furthermore, the obtained classified powder is strictly classified and removed at the same time to remove ultrafine powder and coarse powder using a multi-division classification device (elbow jet classifier manufactured by Tafu Mining Co., Ltd.) that utilizes the Coanda effect.
35% by number of toner particles of 55 μm, 0.5% by volume of toner particles of ≧16 μm, 13% by number of toner particles of 8 to 12.7 μm, 1 black toner particles having a volume average diameter of 8.0 μm were obtained. .

On the other hand, silicic acid fine powder synthesized by a wet method as silicic acid fine powder (trade name, Nip Seal E200. Specific surface area: 110
va2/g, manufactured by Nippon Silikani Gyo Co., Ltd.) was placed in a closed Henschel mixer heated to 70°C, and the amount of silane coupling agent was 5.0% by weight based on the silicic acid fine powder. γ-Aminopropyltriethoxysilane diluted with alcohol was added dropwise to the mixture while stirring at high speed. After completion of the dropping, drying was carried out at a temperature of 120° C. while stirring in the same manner to obtain silane coupling agent-treated silicic acid fine powder (A).

The bulk density of the silicic acid fine powder (A) was 8 parts g/l.

Next, the silicic acid fine powder (A) was crushed with a cosmomizer to obtain a silicic acid fine powder (B) having a bulk density of 55 g/il.

100 parts of the obtained magnetic toner and silicic acid fine powder (B)
1.0 parts were mixed in a Henschel mixer to obtain a non-magnetic toner. A two-component developer (A) was obtained by mixing 10 parts of the non-magnetic toner and 90 parts of a ferrite carrier (volume average diameter: 40 μm).

A commercially available electrophotographic copying machine NP3825 (manufactured by Canon Inc.) equipped with an organic photoconductive photoreceptor without using the two-component developer (a) was used in a high-temperature, high-humidity environment at a temperature of 30°C and a humidity of 90%. When initial expansion was performed below, a clear image with good resolution and no fog was obtained with an image density of 1.36. Subsequently, after performing image development evaluation 20,000 times in a row, the photoreceptor was taken out and observed, and no deposits of silicic acid fine powder (B) were observed on the photoreceptor, indicating that there was no filming. It had not occurred. These results are shown in Table 1.

Comparative Example 1 100 parts of magnetic toner particles obtained in the same manner as in Example 1 and 1.0 part of silicic acid fine powder (A) were mixed in a Henschel mixer to obtain a non-magnetic toner. A two-component developer (a) was obtained using the non-magnetic toner in the same manner as in Example 1.

When the two-component developer (a) was evaluated in the same manner as in Example 1, as shown in Table 1, excellent images were obtained in the initial stage, but Since then, black spots have appeared on the image due to filming of the photoreceptor. Furthermore, when the photoreceptor was taken out and observed after 20,000 cycles, many filmings due to adhesion and accumulation of silicic acid fine powder (A) were observed on the front side of the photoreceptor.

Comparative Example 2 Instead of using the silicic acid fine powder (A) in Example 1, a silicic acid fine powder synthesized by a wet method as a silicic acid fine powder (trade name, Nip Seal E200A, specific surface area 130 rn) was used.
2/g, manufactured by Nippon Silikani Gyo Co., Ltd.) was stirred and the temperature was maintained at approximately 250°C, and silicone oil having an amine in the side chain (viscosity at 25°C: 70 cp
Example 1 except that silicic acid fine powder (C) which was sprayed with 20 parts of amine equivalent (830) and treated for 10 minutes was used.
A two-component developer (2) was obtained in the same manner as above. The bulk density of the resulting silicone oil-treated silicic acid fine powder (C) was 75 g/R.

When the two-component developer was used and evaluated on two days in the same manner as in Example 1, the image density was high, but the lines were rough and the resolution was poor.

When evaluating the image output, black spots due to filming of the photoreceptor appeared on the image from 7,000 times onwards. Further, when the photoreceptor was taken out and observed after 20,000 times, a large number of adhesion and deposits of silicic acid fine powder (C) were observed on the entire surface of the photoreceptor. Furthermore, when the adhesion/deposit was removed, many scratches were observed on the photoreceptor.

Comparative Example 3 The silicone oil-treated silicic acid fine powder (C) obtained in Comparative Example 2 was treated with a costomizer, and the bulk density was 57 g/i.
) was obtained.

A two-component developer (1) was obtained in the same manner as in Example 1, except that the fine silicic acid powder (D) was used instead of the fine silicic acid powder (B) in Example 1.

When the two-component developer (1) was evaluated for image quality in the same manner as in Example 1, as shown in Table 1, excellent images were obtained at the initial stage. After a further 20,000 times of image reproduction,
Some black spots were seen on the front side due to filming of the photoreceptor. On the photoreceptor, fine silicic acid powder (
D) adhesion and deposits were observed.

Example 2 The silicone oil-treated silicic acid fine powder (D) obtained in Comparative Example 3 was further crushed with a costomizer, and the bulk density was 58 g.
/i) A fine silicic acid powder (E) was obtained.

A two-component developer (E) was prepared in the same manner as in Example 1, except that the fine silicic acid powder (E) was used instead of the fine silicic acid powder CB) in Example 1.

When the same image output evaluation as in Example 1 was conducted using a two-component developer (SAI), as shown in Table 1, a clear, high-quality initial image with high image density was obtained, and 20,000 times Even after durability testing on both sides, there was no appearance of black spots due to filming on the image. However, when the photoreceptor was removed and observed, a small amount of fine silicic acid powder (
E) adhesion and deposits were observed.

Example 3 The silicone oil-treated silicic acid fine powder (E) obtained in Example 2 was further crushed with a cosmomizer, and the bulk density was 5.
5 g of fine silicic acid powder (F) was obtained. A two-component developer (power) was obtained in the same manner as in Example 1, except that the fine silicic acid powder CF) was used instead of the fine silicic acid powder CB) in Example 1. When the same image quality evaluation as in Example 1 was conducted using a two-component developer (power), the results were good as shown in Table 1, and even after 20,000 times of image quality, the No filming was observed due to the silicic acid 'a powder (F).

Example 4 Silicone oil-treated silicic acid fine powder obtained in Example 3 (F
) is further crushed with a cosmomizer to give a bulk density of 35 g.
A fine silicic acid powder (G) was obtained. Instead of using the silicic acid fine powder (B) in Example 1, the above silicic acid fine powder (
A two-component developer (Q) was obtained in the same manner as in Example I except that G) was used. Example 1 using two-component developer (K)
When the image output was evaluated in the same manner as in Table 1, the results were good as shown in Table 1, and no filming occurred at all.

Example 5 Silicone oil-treated silicic acid fine powder obtained in Example 4 (G
) was further crushed with a costomizer, and the bulk density was 31g/
j! A fine silicic acid powder (l()) was obtained.

A two-component developer (RI) was obtained in the same manner as in Example 1, except that the fine silicic acid powder (I) was used instead of the fine silicic acid powder (B) in Example 1. Two-component developer (ri)
When the image ratio was evaluated in the same manner as in Example 1, some fogging was observed in the white background area, but other than that, good results were obtained as shown in Table 1.

Comparative Example 4 Silicone oil-treated silicic acid fine powder (I
() was further crushed with a costomizer, and the bulk density was 27g.
/ρ fine silicic acid powder (1) was obtained.

A two-component developer (ke) was obtained in the same manner as in Example 1, except that the fine silicic acid powder (1) was used instead of the fine silicic acid powder (B) in Example 1. When the same image quality evaluation as in Example 1 was carried out using a two-component developer (GE),
Significant fogging occurred in the white background of the image. Furthermore, repeated copying worsened the fogging.

(The following is a blank space) [Results of the invention] I: l l, the characteristics are good, order, light's non-magnetic 1. Even if you do it, you can emit 4 Firminus to 1 person with 5 exposures! Lord.゛Toga! ♂V, long Jtll L1 passing-
1) Clear f1 image with no stains.

4. Brief explanation of 11fI

Claims (2)

[Claims] (1) A non-magnetic toner having a bulk density of 30 to 60 g/l and containing wet-process synthetic fine silicic acid powder treated with a silane coupling agent or silicone oil. (2) The non-magnetic toner according to claim (1), wherein the silicone oil is a modified silicone oil.