JP2001249496A - Nonmagnetic single component color toner and method of manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide nonmagnetic single-component toner which shows stable image density without causing void even in a low transfer electric field and without causing problems such as fog and failure in the follow-up property for a solid image and which has good durability, and to provide a method of manufacturing the toner. SOLUTION: The nonmagnetic single-component color toner contains resin particles consisting of at least a binder resin and a coloring agent, and an additive added to the surface of the resin particles. The additive is added in an aggregated state on the surface of resin particles. In the method of manufacturing the toner, the nonmagnetic single-component color toner containing resin particles consisting of at least a binder resin and a coloring agent and containing an additive added to the surface of the resin particles is manufactured, and the additive added does not disintegrate the aggregated state.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toner used in a developing device for enhancing an electrostatic latent image in an electrophotographic method, in particular, a non-magnetic one-component color toner and a method for producing the same.

[0002]

2. Description of the Related Art In a non-magnetic one-component developing method, which is a mainstream in full-color electrophotographic technology, toner is frictionally charged by a toner replenishing roller and a toner conveying roller (developing roller), and a toner layer thickness regulating member (doctor blade) )
To obtain a sufficient amount of charge and participate in development.
The charged toner is developed on a photoconductor holding a latent image, and is temporarily transferred to an intermediate transfer belt once. By repeating this for four colors (cyan, magenta, yellow, and black), all the toners are stacked on the intermediate transfer belt.
Then, the laminated toner is secondarily transferred to the paper.

The higher the electric field (transfer electric field) applied to the toner during the secondary transfer, the higher the transfer efficiency. However, if the transfer electric field is too high, discharge occurs in the gap between the intermediate transfer belt and the paper, and the effective gap electric field is reduced, resulting in transfer unevenness (mottle).

On the other hand, if the transfer electric field is low, the transfer efficiency is reduced, and the image quality is deteriorated due to poor transfer. In addition, it cannot respond to substrates that are disadvantageous for transfer of postcards, OHP films, etc., and cannot respond to various needs. Further, when the transfer electric field is reduced, “transfer missing”, which is a type of transfer failure, occurs in a portion where the toner tends to concentrate (a so-called edge portion) such as an outline portion or a line drawing portion of an image. It is considered that this is because the edge portion has a larger amount of toner than the normal portion, the toner is likely to aggregate, and the response to the transfer electric field is reduced. In addition, there is a problem that it is difficult to obtain a high-quality image that is faithful to the latent image.

Therefore, it is important to design a toner that does not easily cause agglomeration even when transferring an edge portion, in order to obtain a high-quality image.

Further, in the case of dry toner, it is necessary to improve fluidity and chargeability in order to form a high-quality image. Therefore, conventionally, additives such as inorganic fine particles have been added to and contained in the toner.

[0007]

However, there are a wide variety of additives to be added to and contained in conventional toners.
Their particle sizes also vary. With an additive having a small particle size, the physical distance between the toners becomes short, and the toner tends to aggregate when pressure is generated. In addition, each time printing is performed, the additive tends to be buried in the toner due to friction in the developing device, resulting in a problem that the toner lacks durability. On the other hand, an additive having a large particle diameter has a problem that the surface of a photoreceptor, an intermediate transfer belt, a fixing device, and the like is damaged and characteristics are deteriorated.

In order to solve the above-mentioned problems, the present invention has a stable image density without a hollowing-out phenomenon even under a low transfer electric field, has no problems such as fogging and poor solid followability, and has good durability. It is an object of the present invention to provide a non-magnetic one-component toner and a method for producing the same.

[0009]

According to the present invention, there is provided a non-magnetic one-component color toner comprising at least resin particles comprising a binder resin and a colorant, and an additive added to the surface of the resin particles. A one-component color toner, wherein the additive is added to the surface of the resin particles in an agglomerated state, the production method is at least a binder resin,
A method for producing a non-magnetic one-component color toner containing resin particles composed of a colorant and an additive added to the surface of the resin particles, wherein an additive that does not break up aggregation is added. It is.

[0010]

DETAILED DESCRIPTION OF THE INVENTION The invention according to claim 1 is directed to a non-magnetic one-component color toner containing at least resin particles comprising a binder resin and a colorant, and an additive added to the surface of the resin particles. A manufacturing method in which an additive that does not break up agglomeration is added, which can impart fluidity to the color toner, can suppress aggregation between toners, increase fog, and increase image density. In addition, it is possible to eliminate defects such as poor solid followability and to improve durability.

According to a second aspect of the present invention, in the first aspect, the average particle diameter of the primary particles of the additive which does not break up the aggregation is 25 nm to 50 nm. To prevent aggregation of toner particles, and to eliminate defects such as fogging, increase in image density and poor solid followability, thereby improving durability.

According to a third aspect of the present invention, there is provided a method for producing a non-magnetic one-component color toner comprising at least resin particles comprising a binder resin and a colorant, and an additive added to the surface of the resin particles. Additive that does not break up agglomeration, and
It is to add the additive that disintegrated the coagulation,
Fluidity can be imparted to the color toner, and aggregation between toners can be suppressed. In addition, defects such as fogging, an increase in image density, and poor solid followability can be eliminated, and durability can be improved.

According to a fourth aspect of the present invention, in the third aspect, the average particle diameter of the primary particles of the additive that does not disintegrate the aggregate is 25 nm to 50 nm, and The average particle diameter is set to 20 nm or less, which can impart fluidity to the color toner, suppress aggregation of the toners, and reduce fog, increase in image density and poor solid followability. Defects can be eliminated and durability can be improved.

According to a fifth aspect of the present invention, there is provided a non-magnetic one-component color toner containing at least resin particles comprising a binder resin and a colorant, and an additive added to the surface of the resin particles. The agent is added to the surface of the resin particles in an agglomerated state, which can impart fluidity to the color toner, suppress aggregation of the toners, increase fog and increase image density. In addition, it is possible to eliminate defects such as poor solid followability and to improve durability.

According to a sixth aspect of the present invention, in the fifth aspect, the average particle diameter of the primary particles of the additive is 25 nm to 50 nm.
nm, which can impart fluidity to the color toner, suppress aggregation of the toners, and eliminate defects such as fog, increase in image density, and poor solid followability. Durability can be improved.

According to a seventh aspect of the present invention, there is provided a non-magnetic one-component color toner containing at least resin particles comprising a binder resin and a colorant, and an additive added to the surface of the resin particles. The agent is added to the surface of the resin particles so that the state of aggregation is different, can impart fluidity to the color toner, can suppress aggregation between toners, and can prevent fogging and image formation. Problems such as an increase in density and poor solid followability can be eliminated, and durability can be improved.

According to an eighth aspect of the present invention, in the seventh aspect, the average particle diameter of the primary particles of at least one of the additives having different aggregation states is 25 nm to 50 nm, and the average particle diameter of the primary particles of the other additive is The average particle diameter is set to 20 nm or less, which can impart fluidity to the color toner, suppress aggregation of the toners, and reduce fog, increase in image density and poor solid followability. Defects can be eliminated and durability can be improved.

According to a ninth aspect of the present invention, there is provided a non-magnetic one-component color toner containing at least resin particles comprising a binder resin and a colorant, and an additive added to the surface of the resin particles. The agent, the additive in the aggregated state, the average particle size of the primary particles is smaller than the additive in the aggregated state,
The additive having a small degree of agglomeration is to be added to the surface of the resin particles, and can impart fluidity to the color toner, suppress aggregation of the toners, and prevent fog and image Problems such as an increase in density and poor solid followability can be eliminated, and durability can be improved.

According to a tenth aspect of the present invention, in the ninth aspect, the average particle diameter of the primary particles of the aggregated additive is 25 nm to 50 nm, and the average of the primary particles is larger than that of the aggregated additive. The average particle size of the primary particles of the additive having a small particle size and a small degree of aggregation is set to 20 nm or less, which can impart fluidity to the color toner and suppress the aggregation of the toner particles. While you can
Problems such as fogging, increase in image density and poor solid followability can be eliminated, and durability can be improved.

The invention according to claim 11 is the invention according to claims 5 to 1
In the case of 0, the resin particles contain a charge control agent, and the charge control agent can stabilize the charge amount.

The twelfth aspect of the present invention is the fifth aspect of the present invention.
In 1, the additive is made of an inorganic oxide, and can suitably impart fluidity to the color toner.

According to a thirteenth aspect of the present invention, in the twelfth aspect, the inorganic oxide is made of hydrophobic silica, and the fluidity can be optimally imparted to the color toner.

The invention according to claim 14 is the invention according to claims 5-1.
In 3, the binder resin is made of a polyester resin, has good fixability, and can improve color development and durability as a toner.

According to a fifteenth aspect, in the fourteenth aspect, the polyester resin has a weight average molecular weight of 100
It is set to be not less than 00 and not more than 25,000, so that the offset phenomenon can be prevented, the melting property is good, and the fixing failure can be prevented.

Hereinafter, embodiments of the present invention will be described in detail.

The non-magnetic one-component color toner of the present invention comprises:
It contains at least a binder resin, a colorant and additives, and may further contain a charge control agent.

The following resins can be used as the binder resin.

Polyester resin, epoxy resin, polyol resin, styrene-acrylic resin, polyvinyl chloride, phenolic resin, phenol resin modified with natural resin,
Maleic acid resin, natural resin modified maleic acid resin, acrylic resin, methacrylic resin, acrylic phthalate resin,
Polyvinyl acetate, silicone resin, polyurethane, polyamide resin, polyvinyl butyral, terpene resin, coumarone indene resin, polycarbonate, fluorine resin, aliphatic or aliphatic hydrocarbon resin, aromatic petroleum resin, modified rosin, paraffin, natural Waxes, synthetic waxes and the like can be mentioned, and these resins can be used alone or in combination of two or more.

Further examples include styrenes such as styrene, chlorostyrene, α-methylstyrene and vinylstyrene, monoolefins such as ethylene, propylene, butylene and isobutylene, vinyl acetate, vinyl propionate, vinyl benzoate and butyric acid. Vinyl esters such as vinyl, acrylic acid such as methyl acrylate, ethyl acrylate, butyl acrylate, dodecyl acrylate, octyl acrylate, phenyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, dodecyl methacrylate Alkyl ethers and methacrylic acid alkyl esters, vinyl methyl ether, vinyl ethyl ether, vinyl ethers such as vinyl butyl ether,
Examples include homopolymers or copolymers of vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone, and vinyl isopropenyl ketone.

As typical examples, polystyrene and poly-
Homopolymers of styrene such as p-chlorostyrene and polyvinyltoluene and substituted products thereof, styrene-p-chlorostyrene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-alkyl acrylate Ester copolymer, styrene-alkyl methacrylate copolymer, styrene-α-chloromethyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-vinyl methyl ether copolymer, styrene-vinyl ethyl ether copolymer Copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-acrylonitrile-indene copolymer, styrene-based copolymer such as styrene-maleic anhydride copolymer, polyethylene, ethylene-vinyl acetate copolymer Polymer, ethylene bi Ethylene copolymer of alcohol copolymer, and polypropylene.

These homopolymers or copolymers can be used alone or in combination of two or more.

Among the above binder resins, polyester resins have sharp melting suitability and good fixability. Further, it is possible to improve the coloring property and the durability of the toner, which is particularly preferable.

The weight average molecular weight of the polyester resin is preferably 10,000 or more and 25,000 or less. That is, if it is less than 10,000, there is a problem that a so-called offset phenomenon occurs in which the toner is transferred to the fixing roller in the toner fixing step, and 25,000.
If it is larger than this, there is a problem that the meltability is deteriorated and a fixing failure occurs, which is not preferable.

Further, as the colorant used in the non-magnetic one-component color toner of the present invention, any organic or inorganic pigment or dye is used.

Pigments such as disazo pigments, insoluble azo pigments, azo lake pigments, copper phthalocyanine pigments and the like can be used.
Dyes such as anthraquinone dyes, xanthene dyes, methine dye basic dyes and oil-soluble dyes can be used.
These pigments and dyes can be used alone or in combination of two or more.

The pigments include phthalocyanine blue, indanthrene blue, peacock blue, fast sky blue, induslen blue, aniline blue, calcoil blue, ultramarine blue, permanent red, watching red calcium salt, brilliant carmine , Lake Red, Rose Bengal, Naphthol Yellow, Hansa Yellow, Rhodamine Yellow, Hansa Yellow, Permanent Yellow, Benzidine Yellow, Naphthol Yellow, Chrome Yellow, Quinoline Yellow, Carbon Black, Aniline Black, Acetylene Black, Lamp Black, Alizarin Lake, Bengala , Rhodamine lake, permanent orange, pyrazolone orange, benzine orange, malachite green oki Rate, quinacridone, fast violet, methyl violet lake, as a blue dye or pigment of copper phthalocyanine and derivatives thereof,
C. I. Pigment Blue 15: 3, C.I. I. Pigment Blue 15, C.I. I. Pigment Blue 16, red or red pigments include C.I. I. Pigment Red 5, C.I. I. Pigment Red 3, C.I. I. Pigment Red 2, C.I. I. Pigment Red 6, C.I. I. Pigment Red 7, C.I. I. Pigment Red 57, C.I.
I. Pigment Red 122, C.I. I. Pigment Red 9, C.I. I. Pigment Red 48, C.I. I. Pigment Red 48: 3, C.I. I. Pigment Red 53:
1, C.I. I. Pigment Red 112, C.I. I. Pigment Red 149, C.I. I. Pigment Red 170,
C. I. Pigment Red 168, C.I. I. Pigment Red 188, C.I. I. Pigment Red 194, C.I.
I. Pigment Red 175, C.I. I. Pigment Red 208, C.I. I. Pigment Red 187, C.I. I.
Pigment Red 57: 1, C.I. I. Pigment Red 81, C.I. I. Pigment Red 122, C.I.
I. Pigment Red 49: 1, benzimidazolone monoazo pigments such as C.I. I. Pigment Yellow 151, C.I. I. Pigment Yellow 154, C.I.
I. Pigment Yellow 156, C.I. I. Pigment Yellow 120, C.I. I. Pigment Yellow 17
5. As an acetoacetic acid arylamide-based disazo yellow pigment, C.I. I. Pigment Yellow 12, C.I. I. Pigment Yellow 13, C.I. I. Pigment Yellow 14, C.I. I. Pigment Yellow 17, C.I. I. Pigment Yellow 83, isoindolinone pigments such as C.I. I. Pigment Yellow 110, C.I. I. Pigment Yellow 109, C.I. I. Pigment Yellow 137, C.I. I. Pigment Yellow 173, acetoacetic arylamide monoazo yellow pigment,
C. I. Pigment Yellow 1, C.I. I. Pigment Yellow 3, C.I. I. Pigment Yellow 74,
C. I. Pigment Yellow 97, C.I. I. Pigment Yellow 98 can be used.

As the dye, C.I. I. Direct Blue 1, C.I. I. Direct Blue 2, C.I. I. Acid Blue 9, C.I. I. Acid Blue 15, C.I. I.
Basic Blue 3, C.I. I. Basic Blue 5,
C. I. Modant Blue 7, C.I. I. Direct Red 1, C.I. I. Direct Red 4, C.I. I. Acid Red 1, C.I. I. Basic Red 1, C.I. I. Basic Red 12, C.I. I. Modern Red 30,
C. I. Solvent Red 49, C.I. I. Solvent Red 52, C.I. I. Solvent Red 109, C.I. I.
Solvent Red 58, C.I. I. Solvent Red 8,
C. I. Solvent Yellow 19, C.I. I. Solvent Yellow 77, C.I. I. Solvent Yellow 7
9, C.I. I. Disperse Yellow 164 can be used.

The additives include a flow improver, a release agent,
Lubricant, fixing aid, cleaning improver, conductive material,
Examples of the filler include reinforcing fillers such as extenders and fibrous substances, antioxidants, antioxidants, and anti-offset agents. The additives are added to satisfy various characteristics required for the toner or to improve the characteristics.

Further, these additives include oxides,
Multiple oxides, inorganic oxides, metal oxides, metals, silicon compounds, carbon, carbon compounds, fullerenes, boron compounds, carbides, nitrides, ceramics, and the like, and examples of the inorganic oxides include silica, titania, alumina, Zirconia,
Examples include zinc oxide, magnesium oxide, cerium oxide, strontium titanate, iron oxide, copper oxide, and tin oxide.

Further, various waxes may be added, such as fine particles of fluororesin, fine particles of silicone resin, higher fatty acids such as stearic acid, and metal salts thereof such as zinc stearate and aluminum stearate.

Among the additives of the present invention, inorganic oxides such as silica, alumina, titania, zirconia, etc., which function as a fluidity improver, and the surfaces of these inorganic oxides are It is preferable that the hydrophobic treatment is performed with a silane compound having a nitrogen element-containing substituent or a silicone oil having a nitrogen element-containing substituent such as an amino-modified silicone oil. For example, hydrophobic silica can be used. This additive is externally added to the surface of the toner.

These additives are added alone in a state in which aggregation is not broken, or in a state in which aggregation is not broken and in a state where they are broken.

The average particle size of the primary particles of the additive which does not break up the aggregation is preferably in the range of 25 nm to 50 nm. If the average particle size of the primary particles of the additive is smaller than 25 nm, problems occur in the stability of image density and solid followability, and when it is larger than 50 nm, the photoconductor, toner transport roller (developing roller), and toner layer thickness regulation. There is a problem that the member (doctor blade) and the fixing roller are damaged.

Further, when an additive having an average particle diameter of the primary particles in the range of 25 nm to 50 nm is externally added to the toner surface without breaking the agglomeration, the apparent average particle diameter of the additive on the toner surface is reduced. Diameter is approximately 30nm-60n
m and adhered to the toner surface in an aggregated state. Therefore, the additive has an average primary particle diameter of 25 n.
It is preferably in the range of m to 50 nm, and is added to the surface of the toner in an aggregated state.

The average particle size of the primary particles of the additive for breaking up the aggregation is preferably 20 nm or less. When this is externally added to the surface of the toner, the apparent average particle diameter of the additive on the surface of the toner is 20 nm or less, and the additive is added in a non-aggregated state.

As described above, when the additives having different average particle diameters of the primary particles are used and the aggregation is crushed or not added, the aggregation state on the toner surface is different. Is preferred.

As other additives, release agents include
Low-molecular-weight polypropylene, low-molecular-weight polyethylene, or waxes such as microstalin wax, carnauba wax, sasol wax, and paraffin wax. Further, wax such as polyolefin, polyethylene, and polypropylene also functions as an anti-offset agent. Examples of the lubricant include Teflon (registered trademark), zinc stearate, polyvinylidene fluoride and the like. Low molecular weight polyethylene, low molecular weight polypropylene and the like can be added as a fixing aid. These additives can be used alone or in combination of two or more as needed, and are added internally or externally according to the purpose.

Next, as the charge control agent used in the non-magnetic one-component color toner of the present invention, the following charge control agents can be used.

Examples of the charge controlling agent as the negatively chargeable toner include a chromium-zinc-aluminum-boron complex or salt compound of salicylic acid or a derivative thereof, and a chromium-zinc aluminum-boron complex or salt compound of benzylic acid or a derivative thereof , Tetraphenylborate, chromium azo complex dye, iron azo complex dye, cobalt azo complex dye, chromium zinc of naphtholic acid or its derivative
Surface active agents such as aluminum-boron complex or salt compound, long-chain alkyl carboxylate, and long-chain alkyl sulfonate.

The charge control agent as a positively chargeable toner includes cetyltrimethylammonium bromide, quaternary ammonium salt, N, N-dialkylaminoalkyl (meth) acrylates, and N, N-dialkylaminoalkyl (meth) acrylate. Radical polymerizable copolymers obtained by copolymerizing monomers having a nitrogen-containing functional group of acrylamides, nigrosine dyes and derivatives thereof, triphenylmethane derivatives, quaternary phosphonium salts, quaternary pyridinium salts, guanidine salts, derivatives such as amidine salts And the like.

Further, the non-magnetic one-component color toner of the present invention may contain various additives as necessary.

Next, a method for producing the non-magnetic one-component color toner of the present invention will be described.

The non-magnetic one-component color toner of the present invention can be produced by a kneading and pulverizing method.
Other than the kneading and pulverizing method, there is a polymerization method and the like.

In the kneading and pulverizing method, first, a binder resin, a colorant, a charge control agent, and various internal additives are mixed.

As a mixing method, a Henschel mixer,
It can be performed by a known mixer such as a ball mill.

After being sufficiently mixed in a mixer, the mixture is melt-kneaded, and while the resins are mutually compatible, the colorant, the charge control agent, and the internal additive are dispersed or dissolved.

As a kneading method at this time, a known melt kneader can be used. As the heating kneader, there can be used a device such as a three-roll type, a single screw type, a twin screw type, or a Banbury mixer type that heats and kneads a kneaded material by applying a shearing force.

Next, the melt-kneaded product is cooled and solidified.

Further, this lump is roughly pulverized by a cutter mill or the like, then pulverized by a jet mill pulverizer, and fine powder particles are cut by a classifier such as an airflow classifier to obtain a desired color toner. .

At this time, by appropriately adjusting the classifier, it is possible to obtain color toner resin particles having a weight distribution average particle size and a weight distribution ratio satisfying the desired relationship of the present invention.

The additives of the present invention (for example, silica,
When the agglomeration is broken before adding an inorganic oxide such as alumina, titania or zirconia, the agglomeration of the additive is broken using a pulverizer such as a Henschel mixer or a jet mill.

Then, to the resin particles of the color toner, the additive of the present invention in which the aggregation is broken or the additive which does not break the aggregation is added. In that case, the color toner and the additive can be stirred and mixed using a high-speed stirrer such as a super mixer or a Henschel mixer, and the additive can be added to the toner surface.

The colorant can be contained in the toner at the time of melt-kneading. However, the use of a masterbatch previously melt-kneaded at a high concentration with the binder resin facilitates dispersion of the colorant.

Similarly, the charge control agent can also be used as a masterbatch previously melt-kneaded at a high concentration with the binder resin.

When it is difficult to simultaneously mix and disperse the colorant, the charge control agent, the internal additive, and all other components to be contained in the binder resin, the colorant, the charge control The agent and the internal additive may be melt-kneaded in advance with the binder resin, and then the colorant-dispersed resin, the charge control agent-dispersed resin, the internal additive-dispersed resin and the binder resin may be melt-kneaded.

The particle size distribution of the toner can be measured by various methods. For the measurement of the non-magnetic one-component color toner of the present invention, a Coulter counter was used. The Coulter counter is an apparatus for measuring the number, diameter and volume of fine particles by an electric resistance method. In this invention, it measured using the Coulter counter TA-II type (made by Coulter). The aperture used is a 100 μm aperture. The volume and the number of the toner are measured, and the volume distribution and the number distribution of the particles are calculated. Thereby, the weight distribution average particle diameter calculated from the number distribution average particle diameter and the volume distribution can be obtained.

Further, an electron microscope and an image processing apparatus were used for calculating the average particle diameter of the additive attached to the toner surface. The image processing device includes CSC901NT
(Manufactured by Showa Electric Laboratory) was used. Then, the surface of the toner was photographed with an electron microscope, and this was subjected to image processing to calculate an apparent average particle diameter of the additive adhering to the toner surface.

[0068]

Next, the present invention will be described in detail with reference to examples of the present invention and comparative examples. The present invention is not limited at all by the following Examples and Comparative Examples.

Example 1 The material composition of the toner used in Example 1 is shown below. Binder resin Polyester resin 91.0 parts by weight Colorant C.I. I. Pigment Blue 15: 3 4.5 parts by weight Charge control agent Quaternary ammonium salt 4.5 parts by weight After the binder resin, colorant, and charge control agent, which are materials of the above composition, are mixed well with a ball mill or the like, The mixture was heated and kneaded with a twin-screw kneading extruder, cooled, coarsely pulverized with a cutter mill, finely pulverized with a jet mill, and cut with a gas flow classifier to obtain the color toner resin particles of Example 1. Was.

As a result of measurement using the above-mentioned Coulter Counter TA-II (manufactured by Coulter Inc.), the color toner resin particles of Example 1 had a volume distribution average particle size of 9.70.
(Μm).

Further, based on 100 parts by weight of the color toner resin particles of Example 1, an additive (hydrophobic silica, primary particles having an average particle diameter of 40
nm) was added and mixed and attached using a Henschel mixer to obtain a color toner of Example 1.

Next, the surface of the color toner was photographed with an electron microscope, and the apparent average particle diameter of the additive on the toner surface was calculated by an image processing device CSC901NT (manufactured by Showa Denki R & D Laboratories). The results are shown in (Table 1).

[0073]

[Table 1]

(Comparative Example 1) For comparison, Example 1 was used.
In the same manner as in the above, the materials of the above composition were mixed, heated and kneaded, cooled, coarsely ground, finely ground and classified, and the classifier was appropriately adjusted to obtain color toner resin particles of Comparative Example 1.

Also, as in Example 1, 100 parts by weight of the color toner resin particles of Comparative Example 1
The additive (hydrophobic silica, primary particles having an average particle size of 40 nm) used in the above was subjected to pretreatment by pulverization, 1 part by weight of the additive was added, and mixed and attached using a Henschel mixer. A color toner was obtained.

Next, an image of the surface of the color toner of Comparative Example 1 was taken with an electron microscope, and an image processing device CSC901NT was used.
(Manufactured by Showa Electric Laboratory), the apparent average particle size of the additive on the toner surface was calculated. The results are also shown in (Table 1).

Example 2 In the same manner as in Example 1, the materials having the above compositions were mixed, heated and kneaded, cooled, coarsely ground, finely ground,
By classifying and appropriately adjusting the classifier, the color toner resin particles of Example 2 were obtained.

Further, based on 100 parts by weight of the color toner resin particles of Example 2, an additive (hydrophobic silica, primary particles having an average particle size of 40 n
m) and 1 part by weight of a sub-additive (hydrophobic silica, primary particles having an average particle diameter of 16 n
m) was added and mixed and adhered using a Henschel mixer in the same manner as in Example 1 to obtain a color toner of Example 2.

Example 3 In the same manner as in Example 1, the materials having the above-mentioned compositions were mixed, heated and kneaded, cooled, coarsely pulverized, finely pulverized.
By classifying and appropriately adjusting the classifier, the color toner resin particles of Example 3 were obtained.

Further, based on 100 parts by weight of the color toner resin particles of Example 3, an additive (hydrophobic silica, primary particles having an average particle size of 40 n
m) and 1 part by weight and a sub-additive pretreated by crushing (hydrophobic silica, average particle diameter of primary particles is 16 nm)
Was added and mixed and adhered using a Henschel mixer in the same manner as in Example 1 to obtain a color toner of Example 3.

Further, the non-magnetic one-component color toners of Examples 1 to 3 and Comparative Example 1 were put into a non-magnetic one-component developing device, and a continuous printing life test of 10,000 sheets was performed.

Table 2 shows the test results.

[0083]

[Table 2]

Here, the evaluation methods and evaluation criteria in the evaluation items of (Table 2) will be described.

The "missing transfer" means a missing print at the edge of a character or a square solid portion printed on a plain paper or an OHP film. The degree of the missing transfer is determined by an image processing apparatus. Into a numerical value as the transfer loss rate
Judged. The above-mentioned CSC901NT was used for the image processing apparatus.

The evaluation criteria were as follows: o: transfer loss rate less than 0.04%, Δ: transfer loss rate of 0.04% or more and less than 0.1%, x:
The transfer omission rate was 0.1% or more.

The stability of the image density is to confirm the change over time of the printed image density.
The image density of the zeroth sheet is measured with a Macbeth densitometer (manufactured by Macbeth). Then, evaluation was made based on the difference in the concentration change.

Evaluation criteria are as follows: ：: density change of less than 15%,
Δ: Density change 15% or more and less than 25% X: Density change 15
% Or more.

The fogging is a phenomenon of toner flying to a non-image portion, and the degree of contamination of the non-image portion was determined as a fogging ratio by calculating an occupied area ratio by an image processing apparatus.

Evaluation criteria were as follows: ：: fog rate of less than 0.4%,
Δ: fog rate of 0.4% or more and less than 1.0%, x: fog rate of 1.0% or more.

The solid followability was evaluated by visually checking whether or not image blur occurred in the printing direction when a full solid image was printed.

The evaluation criteria were as follows: ：: no image blur, Δ: low density blur, ×: white blurred portion.

As is apparent from these results, the color toners of Examples 1 to 3 of the present invention were different from Comparative Example 1 in that
It had excellent characteristics.

When comparing Example 1 with Comparative Example 2, that is, when the amounts of the additives (average particle size of 25 nm or more) are the same, the additives of Example 1 in which the additives are not crushed are used. The results showed that there was less omission during transfer, and the image quality (stability of image density, fog, solid followability) was good.

Next, in the comparison between Example 1 and Example 2, that is, when the amounts of the additives (average particle diameter of 25 nm or more) are the same, the sub-additive having a small average particle diameter (average particle diameter of 20 nm) is used.
(nm or less) without disintegration, no significant improvement in transfer omission was obtained.

Further, in comparison with Examples 1 to 3, an additive having a large average particle size (25 nm or more in average particle size) was added without being crushed, and a sub-additive having a small average particle size (average particle size) was added. 2
(0 nm or less) was pulverized and added in Example 3, and the omission during transfer was extremely small, and the image quality (stability of image density, fogging, and solid followability) was also very good.

From the above results, a non-magnetic one-component color toner in which an additive having a large average particle size is added as a pretreatment without disintegrating the aggregation of the additive, and preferably an additive having a small average particle size, A non-magnetic one-component color toner in which sub-additives (average particle diameter of 20 nm or less) are pulverized and added, greatly suppresses the omission phenomenon during transfer in the non-magnetic one-component developing method, and stabilizes image quality. Have been found to be possible.

[0098]

According to the present invention, there is provided an additive having a large particle diameter which damages the surface of a photoreceptor, an intermediate transfer belt, a fixing device, and the like by optimizing the processing conditions in the toner surface processing step and deteriorates the characteristics. Without using a toner, a relatively small additive can be attached to the toner in an agglomerated state to impart fluidity, suppress aggregation of toners, and cause a hollowing-out phenomenon even under a low transfer electric field. It is possible to provide a high-quality non-magnetic one-component color toner having improved durability without problems such as fogging, increase in image density and poor solid followability, and a method for producing the same.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat ゛ (Reference) G03G 9/08 375 G03G 9/08 344 381 (72) Inventor Aso Toda 1006 Odakadoma, Kazuma, Kadoma, Osaka Matsushita Electric Industrial Co., Ltd. F-term (reference) 2H005 AA01 AA06 AA08 AA21 AB10 CA08 CA21 CB07 CB13 DA01 EA05 EA06 FA07

Claims (15)

[Claims] 1. A method for producing a non-magnetic one-component color toner comprising at least resin particles comprising a binder resin and a colorant, and an additive added to the surface of the resin particles,
A method for producing a non-magnetic one-component color toner, comprising adding an additive that does not break up aggregation. 2. The method for producing a non-magnetic one-component color toner according to claim 1, wherein the average particle diameter of the primary particles of the additive which does not disintegrate the aggregation is 25 nm to 50 nm. 3. A method for producing a non-magnetic one-component color toner comprising at least resin particles comprising a binder resin and a colorant, and an additive added to the surface of the resin particles,
A method for producing a non-magnetic one-component color toner, comprising adding an additive that does not break up aggregation and an additive that breaks up aggregation. 4. The average particle size of the primary particles of the additive that does not break up the aggregation is 25 nm to 50 nm, and the average particle size of the primary particles of the additive that breaks the aggregation is 20 nm or less. The method for producing a non-magnetic one-component color toner according to claim 3, wherein 5. A non-magnetic one-component color toner containing at least resin particles comprising a binder resin and a colorant, and an additive added to the surface of the resin particles, wherein the additive is in an aggregated state. A non-magnetic one-component color toner, which is added to the surface of the resin particles. 6. An additive having an average particle diameter of primary particles of 2
6. The non-magnetic one-component color toner according to claim 5, wherein the thickness is 5 nm to 50 nm. 7. A non-magnetic, one-component color toner containing at least resin particles comprising a binder resin and a colorant, and an additive added to the surface of the resin particles, wherein the additive is in an aggregated state. Characterized in that the non-magnetic one-component color toner is added to the surface of the resin particles. 8. An average particle diameter of primary particles of at least one of the additives having different aggregation states is 25 nm to 50 nm.
And the average particle size of the primary particles of the other additive is 20
The non-magnetic one-component color toner according to claim 7, wherein the particle diameter is not more than nm. 9. A non-magnetic one-component color toner containing at least resin particles comprising a binder resin and a colorant, and an additive added to the surface of the resin particles, wherein the additive is agglomerated. An additive in a state, wherein the additive having a smaller average particle diameter of primary particles than the additive in the aggregated state and having a small degree of aggregation is added to the surface of the resin particles. Magnetic one-component color toner. 10. The average particle diameter of primary particles of the additive in the aggregated state is 25 nm to 50 nm, and the average particle diameter of primary particles is smaller than that of the additive in the aggregated state.
The average particle size of the primary particles of the additive whose cohesion is also small is
10. The non-magnetic one-component color toner according to claim 9, wherein the thickness is 20 nm or less. 11. The non-magnetic one-component color toner according to claim 5, wherein said resin particles contain a charge control agent. 12. The non-magnetic one-component color toner according to claim 5, wherein said additive comprises an inorganic oxide. 13. The non-magnetic one-component color toner according to claim 12, wherein said inorganic oxide is made of hydrophobic silica. 14. The non-magnetic one-component color toner according to claim 5, wherein said binder resin is made of a polyester resin. 15. The non-magnetic one-component color toner according to claim 14, wherein the polyester resin has a weight average molecular weight of 10,000 or more and 25,000 or less.