KR100484723B1 - Color toner composition having superior transcription efficiency and method for preparing thereof - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color toner composition and a method for producing the same, in particular, after annealing the toner base particles at a temperature of 45 to 65 ° C. for 5 to 12 hours, silica and inorganic fine particles are attached thereto to reduce the amount of residual toner. In addition, the present invention relates to a method for producing a color toner having high high-efficiency efficiency with low charge change and stable high transfer efficiency, low environmental dependence, and long-term stability with which stable image quality can be obtained over a long period of time.

Description

Color toner composition with excellent transfer efficiency and manufacturing method thereof {COLOR TONER COMPOSITION HAVING SUPERIOR TRANSCRIPTION EFFICIENCY AND METHOD FOR PREPARING THEREOF}

The present invention relates to a color toner composition and a method of manufacturing the same, and more particularly, by reducing the amount of residual toner, it is possible to obtain a high transfer efficiency with little charge change and a stable environment, and a stable image quality over a long period of time. The present invention relates to a color toner composition having high long-term stability with which long-term stability can be obtained, and a manufacturing method thereof.

In recent years, with the rapid spread of PCs and networks in offices, the copier and printer markets, which used to be black and white, have been changing to full color. In particular, recent market demands for high quality, high reliability, as well as miniaturization, light weight, low price, high speed, and further, environmental response such as low energy, recycling, and the like. In addition, various improvements have been made to the image forming method and the toner used therefor to cope with this.

Electrophotographic image forming apparatus is generally

1. The charging process of uniformly charging the surface of the drum,

2. an exposure process of exposing the surface of the drum and forming an electrostatic latent image;

3. Develop a latent image on the surface of the drum using toner formed on the surface of the developing roller.

   Developing process of obtaining a high toner image,

4. A transfer step of transferring the toner image onto the transfer material;

5. a fixing step of fixing the toner image on the transfer material, and

6. Cleaning ball for removing toner remaining on the surface of the drum in the transfer process

   It is composed of tablets.

Basic characteristics required for the toner for each process of the electrophotographic image forming apparatus as described above are as follows. The developing process requires a suitable amount of toner charge, charge retention, environmental stability, transfer process requires good transfer performance, fixing process requires low temperature fixability, offset resistance, and cleaning process requires cleaning. Performance, pollution resistance, etc. are required. In particular, in recent years, the above characteristics are increasingly complex and complex due to high quality, high speed, and colorization.

Accordingly, there is a method of mixing four colors directly in the photosensitive drum when forming a color image in the transfer process. In addition, an indirect transfer type image forming apparatus using an intermediate transfer member is used for more accurate color reproduction. The intermediate transfer member is used to transfer the toner image on the surface of the drum by color onto the intermediate transfer member, and then the image is transferred from the intermediate transfer member. As a method of transferring to a transfer material, it is mainly used in full color printers in recent years due to the high speed and high image quality.

However, since the indirect transfer type image forming apparatus increases the number of transfer steps of the toner, a higher and more accurate transfer performance is required for higher image quality, and additive, toner shape, and surface structure control technology for more stable charging performance or transfer efficiency for toner. Etc. are required.

In addition, in the cleaning process, it is important not only to reduce the size and cost of the apparatus, but also to reduce the transfer residual toner amount and reduce the cleaning apparatus in order to improve environmental dependence. In particular, in the full color image forming apparatus using three colors of yellow, magenta, cyan, or four colors of toner plus black, transfer residual toner is a serious problem.

In order to avoid new problems in such a transfer process and a cleaning process, it is important to reduce the amount of residual toner, and for this purpose, it is necessary to improve the transfer efficiency of the toner. In order to improve the transfer efficiency, it is necessary to lower the adhesive force between the toner and the photosensitive drum.

As a method for lowering the adhesive force between the toner and the photosensitive drum, there is a method in which toner contains peelable fine particles such as silica. This improves the transfer efficiency by lowering the adhesion between the toner and the drum by interposing the toner and the drum by using fine particles. In order to obtain high transfer efficiency, the coverage of the toner surface by the fine particles must be set high. There is a problem in that the amount of added is increased, deterioration of toner chargeability, adhesion of fine particles to the latent electrostatic image bearing member, filming, impairment of fixation, and the like occur. In particular, since silica particles have high environmental dependence, problems such as burn density stain at low temperature and low humidity, and non-image contamination at high temperature and high humidity may occur.

On the other hand, as a method of improving the environmental dependence of toner charging, there is known a method of adding inorganic fine particles such as titanium oxide having lower electrical resistance and better charge exchangeability than silica particles. However, the use of inorganic fine particles with low electrical resistance tends to change the charge distribution of the toner, and the transfer failure of the secondary transfer when the intermediate transfer member is used or the retransfer of the reverse polarity toner during the multiple transfer of the full color toner. ) Is easy to occur.

As a method to solve this problem, there is a method of controlling the resistance by surface treatment of inorganic particles having low resistance such as titanium oxide with a silane coupling agent, etc. Deterioration, the function of enhancing the original charge exchangeability is deteriorated, and there are problems such as deterioration of the toner fluidity and occurrence of blocking due to liberated aggregated particles.

Accordingly, research on color toners with little charge change, excellent transfer efficiency and long-term stability, and low environmental dependence has been required.

SUMMARY OF THE INVENTION In order to solve the above problems, an object of the present invention is to provide a color toner composition having little charge change, excellent transfer efficiency, and long term stability.

It is another object of the present invention to provide a method for producing a color toner having high photoelectric efficiency, which has little change in charging, excellent transfer efficiency, stable image quality over a long period of time, and low environmental dependence.

In order to achieve the above object, the present invention provides a color toner composition,

a) 100 parts by weight of the annealed toner base particles;

b) 1.0 to 3.0 parts by weight of silica coated on the toner base particles; And

c) 0.2 to 2.0 parts by weight of inorganic fine particles coated on the toner base particles

It provides a color toner composition comprising a.

In addition, the present invention provides a method of producing a color toner,

a) annealing the toner base particles at a temperature of 45 to 65 DEG C for 5 to 12 hours

   Keying up; And

b) silica on the surface of the toner base particles of step a), and ii) inorganic fine particles.

   Attaching Step

It provides a method of manufacturing a color toner comprising a.

Hereinafter, the present invention will be described in detail.

The inventors of the present invention have been studying a method for producing a color toner for electrostatic image development that can reduce the charge change in toner transfer, has high transfer efficiency, has little environmental dependence, and can obtain stable image quality over a long period of time. After the annealing (annealing) at a constant temperature and time, as a result of attaching silica and titanium oxide, it was confirmed that a high transfer efficiency can be obtained, to complete the present invention based on this.

The present invention provides a color toner composition comprising 1.0 to 3.0 parts by weight of silica coated on the toner base particles, and 0.2 to 2.0 parts by weight of inorganic fine particles, in 100 parts by weight of the annealed toner base particles.

The present invention also provides a method for producing a color toner, wherein the toner base particles are annealed at a temperature of 45 to 65 ° C. for 5 to 12 hours, and then silica and inorganic fine particles are attached thereto.

The annealing of step a) is preferably carried out at a temperature of 45 to 65 ℃ for 5 to 12 hours. The annealing shows the difference of effect by temperature and time, and when the annealing temperature is less than 45 ℃, the effect is insignificant, and when the annealing temperature exceeds 65 ℃, the melt adhesion of the toner base particles (melt adhesion) occurs have. In addition, when the annealing is less than 5 hours, the effect is insignificant, when more than 12 hours there is a problem that melt adhesion occurs.

Step b) is a step of attaching silica to the surface of the toner base particles annealed as in step a), and ii) titanium oxide, wherein the silica of b) v) is based on 100 parts by weight of the toner base particles It is preferably contained in 1.0 to 3.0 parts by weight, and the specific surface area of silica is preferably 20 to 200 m 2 / g, more preferably 30 to 150 m 2 / g.

The silica used in the present invention can be obtained even in the untreated state, but when the hydrophobization treatment can further improve the effect.

As the silane coupling agent used for the hydrophobization treatment of silica, dimethyldichlorosilane, trimethylchlorosilane, methyltrichlorosilane, arylphenyldichlorosilane, benzyldimethylchlorosilane, bromine methyldimethylchlorosilane, P-chlorophenyltrichlorosilane, 3 -Chloropropyltrimethoxy, vinyltriethoxysilane, vinyltriacetoxysilane, divinylcrosilane, or hexamethylenedisiragen and the like can be used.

In addition, silica can be hydrophobized with silicone oil to reduce fog and backgruond, for example, dimethylsilicone oil having a viscosity of 50-10000 cps, methylphenylsilicone oil, methylhydrogen silicone oil, Alkyl modified silicone oil, fluorine modified silicone oil, alcohol modified silicone oil, amino modified silicone oil, epoxy modified silicone oil, epoxypolyether modified silicone oil, phenol modified silicone oil, carboxy modified silicone oil, etc. can be used.

The hydrophobization treatment with the silicone oil is not particularly limited as long as the silicone oil adheres to the surface of the inorganic fine particles. Examples of the hydrophobic treatment with the silicone oil include diluting the inorganic fine particles in a mixing bath, followed by stirring and diluting the silicone oil in a solvent, followed by spraying. There is a method of heating and drying in a mixing tank for a predetermined time while continuing to stir it.

The method of attaching silica to the surface of the toner base particles may be carried out by mixing using a turbine type stirrer, a Henschel mixer, or a super mixer, and the silica on the surface of the toner base particles may be weakly attached to the toner base particles. It may be attached, or a part of silica may be fixed to the surface of the toner base particles in a buried state.

Titanium dioxide, aluminum oxide, zinc oxide, magnesium oxide, cerium oxide, iron oxide, copper oxide, or tin oxide may be used as the inorganic fine particles of b) ii). Particularly, titanium oxide, which is easily modified and purchased, may be used. desirable.

It is preferable that the average particle diameter of the said inorganic fine particle is 0.5-2 micrometers, More preferably, it is 0.5-1.5 micrometers. This ensures sufficient fluidity in the toner to maintain a high image density even when outputting a large amount for a long time. When the average particle diameter is less than 0.5 μm or more than 2 μm, charging characteristics and image concentrations are lowered, and there is a problem of lowering the improvement effect of charging fluidity and drum contamination.

The content of the inorganic fine particles is preferably included in 0.2 to 2.0 parts by weight, more preferably 0.3 to 1.5 parts by weight based on 100 parts by weight of the toner base particles. If the content is less than 0.2 parts by weight, the charging characteristic is gradually lowered, and if it exceeds 2.0 parts by weight, there is a problem that the image concentration is lowered.

In addition, the toner base particles include a binder resin and a colorant as essential components, and may further include a flow promoter, a mold release agent, a charge control agent, and the like.

As the binder resin, styrene resin, epoxy resin, polyester resin, polyurethane resin, or the like can be used.

As a monomer used for the said styrene resin, Styrene, such as styrene, (alpha) -methylstyrene, a crawl styrene; Acrylic esters such as methyl acrylate, ethyl acrylate, propyl acrylate, acrylic acid, octyl acrylate, and alkyl acrylates; Methacrylic acid esters such as methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, octyl methacrylate, stearyl methacrylate, glycidyl methacrylate and alkyl methacrylate; Or acrylonitrile, maleic acid, maleic acrylate, methyl methacrylate, methyl acrylate, vinyl chloride, vinyl acetate, vinyl benzoate, vinyl methyl ketone, vinyl hexyl ketone, vinyl methyl ester, vinyl ethyl ester, or vinyl isobutyl ester Vinyl monomers, such as these, can be used.

The colorants are carbon blacks, magnetic powders, dyes, and pigments such as nigurosine dyes, aniline blue, carcoyl blue, chrome yellow, quinoline yellow, ultramarine blue, dupont oil red, methylene blue chloride, phthalocyanine blue, Malachite green, oxalate, lamp black, rose bengal, CI pigment red 48: 1, CI pigment red 122, CI pigment red 57: 1, CI pigment yellow 97, CI pigment yellow 12, CI pigment yellow 180, CI pigment yellow 12, CI pigment blue 15: 1, or CI pigment blue 15: 3 etc. can be used. In addition, the colorant is preferably included 1 to 20 parts by weight based on 100 parts by weight of the toner base particles.

Examples of the flow promoter include SiO ₂ , TiO ₂ , MgO, Al ₂ O ₃ , MnO, ZnO, Fe ₂ O ₃ , CaO, which have been subjected to hydrophobization treatment such as hexamethyldisilazane, dimethyldichlorosilane, octyltrimethoxysilane, and the like. Inorganic oxide fine particles such as BaSO ₄ , CeO ₂ , K ₂ O, Na ₂ O, ZrO ₂ , CaO · SiO, K ₂ O · (TiO ₂ ) _n , or Al ₂ O ₃ · 2SiO ₂ can be used.

The release agent may be various waxes or low molecular weight olefin resins such as polypropylene, polyethylene, and propylene-ethylene copolymers, and preferably polypropylene.

In addition, the charge control agent may include 0.5 to 5% by weight, in the case of negative charge, a metal azo dye or a salicylic acid compound may be used, and in the case of positive charge, a quaternary ammonium salt may be used.

In the present invention, the specific surface area of silica means the specific surface area measured by the BET method, and the value thereof can be measured by a commercially available high precision automatic gas adsorption device or the like. The above-described measuring device obtains the BET specific surface area (S, m 2 / g) by measuring the amount of gas adsorption necessary for forming a monolayer on the surface of the hydrophobic silica particles using an inert gas, particularly nitrogen gas, as the adsorption gas.

Hereinafter, preferred examples are provided to help understanding of the present invention, but the following examples are merely to illustrate the present invention, and the scope of the present invention is not limited to the following examples.

EXAMPLE

Example 1

(Preparation of cyan toner base particles)

94 parts by weight of polyester resin (molecular weight: 2.5 × 10 ⁵ ), 5 parts by weight of phthalocyanine P.BI.15: 3, 1 part by weight of metal azo salt and 3 parts by weight of low molecular weight polypropylene as a charge control agent After mixing, the mixture was melt kneaded at a temperature of 165 ° C. in a biaxial melt kneader, finely ground in a jet mill grinder, and then classified in a wind classifier to prepare toner base particles having a volume average particle diameter of 9.2 μm.

(Toner mother particle annealing and color toner manufacturing)

After annealing the toner base particles prepared as described above in a convention oven at 50 ° C. for 10 minutes, the specific surface area is 60 m 2 / g based on 100 parts by weight of the toner base particles, and dimethyl silicone oil 1.5 parts by weight of hydrophobic silica surface-hydrophobized with (dimethyl slicone oil) and 0.5 parts by weight of titanium oxide having an average particle diameter of 0.9 μm were attached to the surface of the toner base particles to prepare a color toner.

Examples 2-9

As shown in Table 1 in Example 1 was carried out in the same manner as in Example 1, except that the content of silicon and titanium oxide.

division toner Silica Titanium oxide Temperature (℃) Hours (hr) Specific surface area (㎡ / g) Silicone oil Content (parts by weight) Average particle size (㎛) Content (parts by weight) Example 2 50 10 60 Dimethyl silicone oil 1.5 0.9 1.0 Example 3 50 10 60 Dimethyl silicone oil 1.5 0.9 1.5 Example 4 50 10 60 Dimethyl silicone oil 2.0 0.9 0.5 Example 5 50 10 60 Dimethyl silicone oil 2.0 0.9 1.0 Example 6 50 10 60 Dimethyl silicone oil 2.0 0.9 1.5 Example 7 50 10 60 Dimethyl silicone oil 2.5 0.9 0.5 Example 8 50 10 60 Dimethyl silicone oil 2.5 0.9 1.0 Example 9 50 10 60 Dimethyl silicone oil 2.5 0.9 1.5

Comparative Examples 1 to 54

In Example 1, as shown in Table 2 below, the temperature and time for annealing the toner base particles are different, the specific surface area of silicon, the silicon oil and the content during hydrophobization treatment, and the average particle diameter and content of titanium oxide are different. The same procedure as in Example 1 was conducted except for the one.

division toner Silica Titanium oxide Temperature time Specific surface area Silicone oil content Average particle diameter content Comparative Example 1 25 10 60 Dimethyl silicone oil 1.5 0.9 0.5 Comparative Example 2 25 10 60 Dimethyl silicone oil 1.5 0.9 1.0 Comparative Example 3 25 10 60 Dimethyl silicone oil 1.5 0.9 1.5 Comparative Example 4 25 10 60 Dimethyl silicone oil 2.0 0.9 0.5 Comparative Example 5 25 10 60 Dimethyl silicone oil 2.0 0.9 1.0 Comparative Example 6 25 10 60 Dimethyl silicone oil 2.0 0.9 1.5 Comparative Example 7 25 10 60 Dimethyl silicone oil 2.5 0.9 0.5 Comparative Example 8 25 10 60 Dimethyl silicone oil 2.5 0.9 1.0 Comparative Example 9 25 10 60 Dimethyl silicone oil 2.5 0.9 1.5 Comparative Example 10 35 10 60 Dimethyl silicone oil 1.5 0.9 0.5 Comparative Example 11 35 10 60 Dimethyl silicone oil 1.5 0.9 1.0 Comparative Example 12 35 10 60 Dimethyl silicone oil 1.5 0.9 1.5 Comparative Example 13 35 10 60 Dimethyl silicone oil 2.0 0.9 0.5 Comparative Example 14 35 10 60 Dimethyl silicone oil 2.0 0.9 1.0 Comparative Example 15 35 10 60 Dimethyl silicone oil 2.0 0.9 1.5 Comparative Example 16 35 10 60 Dimethyl silicone oil 2.5 0.9 0.5 Comparative Example 17 35 10 60 Dimethyl silicone oil 2.5 0.9 1.0 Comparative Example 18 35 10 60 Dimethyl silicone oil 2.5 0.9 1.5 Comparative Example 19 50 10 60 Dimethyl silicone oil 0.5 0.9 0.1 Comparative Example 20 50 10 60 Dimethyl silicone oil 0.5 0.9 1.0 Comparative Example 21 50 10 60 Dimethyl silicone oil 0.5 0.9 2.5 Comparative Example 22 50 10 10 Dimethyl silicone oil 2.5 0.13 0.5 Comparative Example 23 50 10 10 Dimethyl silicone oil 2.5 0.9 1.0 Comparative Example 24 50 10 10 Dimethyl silicone oil 2.5 3 1.5 Comparative Example 25 50 10 280 Hexamethyldisilazane 1.5 0.13 0.5 Comparative Example 26 50 10 280 Hexamethyldisilazane 2.0 0.9 0.1 Comparative Example 27 50 10 280 Hexamethyldisilazane 2.0 3 1.0 Comparative Example 28 60 10 60 Dimethyl silicone oil 2.0 0.13 2.5 Comparative Example 29 60 10 60 Dimethyl silicone oil 0.5 0.9 1.0 Comparative Example 30 60 10 60 Dimethyl silicone oil 2.0 3 1.0 Comparative Example 31 60 10 280 Hexamethyldisilazane 3.5 0.13 1.0 Comparative Example 32 60 10 280 Hexamethyldisilazane 3.5 0.9 2.5 Comparative Example 33 60 10 280 Hexamethyldisilazane 0.5 3 1.0 Comparative Example 34 50 5 10 Dimethyl silicone oil 2.0 0.13 0.1 Comparative Example 35 50 5 10 Dimethyl silicone oil 2.0 0.9 1.0 Comparative Example 36 50 5 10 Dimethyl silicone oil 2.0 3 2.5 Comparative Example 37 50 5 60 Dimethyl silicone oil 0.5 0.13 1.0 Comparative Example 38 50 5 60 Dimethyl silicone oil 3.5 3 1.0 Comparative Example 39 50 5 280 Hexamethyldisilazane 3.5 0.13 2.5 Comparative Example 40 50 5 280 Hexamethyldisilazane 0.5 0.9 0.1 Comparative Example 41 50 5 280 Hexamethyldisilazane 2.5 3 1.0 Comparative Example 42 50 20 10 Dimethyl silicone oil 2.0 0.13 0.1 Comparative Example 43 50 20 10 Dimethyl silicone oil 2.0 0.9 1.0 Comparative Example 44 50 20 10 Dimethyl silicone oil 2.0 3 2.5 Comparative Example 45 50 20 60 Dimethyl silicone oil 0.5 0.13 1.0 Comparative Example 46 50 20 60 Dimethyl silicone oil 2.0 0.9 1.0 Comparative Example 47 50 20 60 Dimethyl silicone oil 3.5 3 1.0 Comparative Example 48 50 20 280 Hexamethyldisilazane 3.5 0.13 2.5 Comparative Example 49 50 20 280 Hexamethyldisilazane 0.5 0.9 0.1 Comparative Example 50 50 20 280 Hexamethyldisilazane 2.5 3 1.0

Experimental Example 1

The color toners prepared in Examples 1 to 9 and Comparative Examples 1 to 50 were measured using the HP4500 printer (Hewlett-Packard Co., Ltd.) in the following manner to measure image density, transfer efficiency, and long-term properties. Table 3 shows.

A) Image density (I.D)-Macbeth reflection densitometer RD918 for solid area images

    Was measured.

B) Transfer efficiency: Consumption of 500 sheets for each of the above 5,000 printed sheets

    Calculate the net consumption minus waste to

    % Was calculated.

    A: 80% or more transfer efficiency B: 70 ~ 80% transfer efficiency

    C: transfer efficiency 60-70% D: transfer efficiency 50-60%

C) Long-term: Print up to 5,000 sheets to check whether I.D and transfer efficiency are maintained.

    Due to

    A: Up to 5,000 sheets I.D. 1.4 or more, 80% transfer efficiency

    B: up to 5,000 sheets I.D. 1.2 or more, 70% or more transfer efficiency

    C: up to 5,000 sheets I.D. 1.0 or more, transfer efficiency 60% or more

    D: Up to 5,000 sheets I.D. 0.8 or more, transfer efficiency 50% or more

division Burn density Transcription efficiency Long-term reliability division Burn density Transcription efficiency Long-term reliability Example 1 1.44 A A Comparative Example 22 1.28 C C Example 2 1.46 A A Comparative Example 23 1.30 C C Example 3 1.45 A A Comparative Example 24 1.31 C C Example 4 1.44 A A Comparative Example 25 1.29 C C Example 5 1.51 A A Comparative Example 26 1.29 C C Example 6 1.47 A A Comparative Example 27 1.29 C C Example 7 1.45 A A Comparative Example 28 1.22 C C Example 8 1.44 A A Comparative Example 29 1.20 C D Example 9 1.42 A A Comparative Example 30 1.19 C D Comparative Example 1 1.18 D D Comparative Example 31 1.16 D D Comparative Example 2 1.20 C D Comparative Example 32 1.17 D D Comparative Example 3 1.18 D D Comparative Example 33 1.18 D D Comparative Example 4 1.18 D D Comparative Example 34 1.20 C D Comparative Example 5 1.20 C D Comparative Example 35 1.21 C D Comparative Example 6 1.16 D D Comparative Example 36 1.18 C D Comparative Example 7 1.18 D D Comparative Example 37 1.20 C D Comparative Example 8 1.15 D D Comparative Example 38 1.16 D D Comparative Example 9 1.20 C D Comparative Example 39 1.14 D D Comparative Example 10 1.16 D D Comparative Example 40 1.18 D D Comparative Example 11 1.20 D D Comparative Example 41 1.15 C D Comparative Example 12 1.18 D D Comparative Example 42 1.16 D D Comparative Example 13 1.15 D D Comparative Example 43 1.17 C D Comparative Example 14 1.19 C D Comparative Example 44 1.13 D D Comparative Example 15 1.16 D D Comparative Example 45 1.15 D D Comparative Example 16 1.18 D D Comparative Example 46 1.16 D D Comparative Example 17 1.14 D D Comparative Example 47 1.17 D D Comparative Example 18 1.14 D D Comparative Example 48 1.17 C D Comparative Example 19 1.30 C B Comparative Example 49 1.18 D D Comparative Example 20 1.34 B C Comparative Example 50 1.19 C C Comparative Example 21 1.28 C C

Through Table 4, after annealing the toner base particles at a temperature of 45 to 65 ℃ for 5 to 12 hours according to the present invention, 1.0 to 3.0 parts by weight of silica having a specific surface area of 20 to 200 m 2 / g, and It was confirmed that the color toners of Examples 1 to 9 to which 0.2 to 2.0 parts by weight of the inorganic fine particles having an average particle diameter of 0.5 to 2 µm were attached were superior to the toners of Comparative Examples 1 to 40 in terms of image density, transfer efficiency, and long-term properties. .

As described above, the color toner of the present invention can reduce the amount of residual toner, not only to obtain a stable high transfer efficiency with little charge change, but also to have low environmental dependence, and to provide stable image quality over a long period of time. This has an advantage.

Claims (6)

a) 100 parts by weight of annealed toner base particles consisting of a binder resin selected from the group consisting of styrene resins, epoxy resins, polyester resins and polyurethane resins and a colorant selected from the group consisting of carbon black, magnetic powder, dyes and pigments ; b) 1.0 to 3.0 parts by weight of silica coated on the toner base particles; And c) 0.2 to 2.0 parts by weight of inorganic fine particles selected from the group consisting of titanium dioxide, aluminum oxide, zinc oxide, magnesium oxide, cerium oxide, iron oxide, copper oxide and tin oxide coated on the toner base particles Color toner composition comprising a. a) annealing the toner base particles at a temperature of 45 to 65 DEG C for 5 to 12 hours    Keying up; And b) silica on the surface of the toner base particles of step a), and ii) inorganic fine particles.    Attaching Step Method of manufacturing a color toner comprising a. The method of claim 2, I) 1.0 to 3.0 parts by weight of silica, and ii) 0.2 to 2.0 parts by weight of inorganic fine particles, based on 100 parts by weight of the toner base particles of step a). The method of claim 2, A method for producing a color toner, wherein the silica specific surface area of b) i) is 20 to 200 m 2 / g. The method of claim 2, The method of producing a color toner wherein the average particle diameter of the inorganic fine particles of b) ii) is 0.5 to 2 m. 2. The color toner composition of claim 1, wherein the toner base particles further comprise a flow promoter, a releasing agent or a charge control agent.