JP3010326B2 - Method for manufacturing color toner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color toner used in electrophotography, electrostatic printing, magnetic recording and the like.
The present invention relates to a method for producing a color toner by a dry method.

[0002]

2. Description of the Related Art In electrophotography, a photoconductive substance is generally used to form an electric latent image on a photoreceptor by various methods, and then the latent image is developed using toner. As necessary, a method of transferring a toner image onto a transfer material such as paper and fixing the toner image by various methods to obtain a copy is used.

[0003] In general, toners are classified into dry toners and wet toners. In recent years, dry toners have become the mainstream due to problems such as evaporation, recovery, and odor of solvents in wet toners.

[0004] Toner is a powder for forming an image, and it is necessary for the toner particles to have many functions in order to form an image accurately. For example, chargeability, transportability, fixability, coloring power, storage stability, and the like. Therefore, the toner is prepared as a mixture of various raw materials.

[0005] As a method for producing a dry toner, a pulverization method,
Although a polymerization method and an encapsulation method are mentioned, a pulverization method is generally used in general.

As a general method for producing a color toner by a pulverizing method, there are a binder resin for fixing to a material to be transferred, various coloring agents for giving a color as a color toner, and other additives such as a charge control agent. Dry mixing of raw materials
Then, using a general-purpose kneading device such as a kneader, roll mill, or extruder, while applying temperature, compressive force,
Melt kneading by shearing force, and after cooling and solidifying, perform coarse pulverization as necessary to produce a kneaded crushed product, and then finely pulverize to an appropriate particle size as a color toner using a fine pulverizing device such as a jet mill .

After that, if necessary, classification is carried out by various classifiers, and the particle size is adjusted to a particle size distribution capable of exhibiting sufficient performance as a color toner. Further, if necessary, a fluidity improver, a lubricant, an abrasive and the like are dry-mixed and used as a color toner. When used as a so-called two-component toner, it is mixed with various magnetic carriers and then used as a developer for image formation.

One of the factors relating to the performance of a color toner is coloring power and transparency. Although the coloring power and the transparency are affected by the amount of the coloring agent, they are also greatly affected by the degree of dispersion of the coloring agent.

[0009] In the color toner, the dispersion state of the various raw materials in the color toner particles is substantially determined by the raw material mixing step and the kneading step in the production process of the color toner by the pulverization method. As a production apparatus used for mixing the raw materials, a high-speed stirring type mixing apparatus such as a container rotary type mixer such as a V blender or a W cone or a Henschel mixer is generally used, and the mixture prepared by these apparatuses is kneaded or kneaded. Melt and knead with an extruder.

[0010] However, the kneaded product obtained by the above-mentioned production method is inferior in coloring power and transparency as a color toner because the dispersion state of the colorant in the binder resin is particularly insufficient.

Therefore, a manufacturing method partially remedying these problems is a first kneading step and a second kneading step shown in the conventional example of FIG.
This is a production method having a kneading step, i.e., in the first kneading step, kneading a high-concentration colorant-containing resin containing at least a colorant in the kneaded product obtained in the second kneading step and containing the coloring agent in the second kneading step. In the kneading step, if necessary, additives such as a binder resin and a charge control agent are further added and diluted and mixed, and then kneaded using a kneader such as a kneader or an extruder to obtain a color toner kneaded material. . However, a typical kneader used in the first kneading step is a three-roll mill, but the kneading operation is a batch operation, and various kneading conditions, i.e., kneading temperature, roll rotation speed, clearance between rolls, and rotation of each roll are used. While the conditions such as the ratio and the number of passes (the number of treatments) are delicately changed, the worker is constantly kneading, and very skill is required to uniformly control the dispersion state of the coloring agent and the like in the kneaded material. It is a process. Furthermore, in the number of passes, at least two times,
Preferably, batch processing is preferably repeated four or more times, and this is a production method in which the work is performed by human means each time, and there is also an uneasiness in terms of the properties of the machine and the safety.

Further, in terms of quality, the performance required for color toners has become more severe in recent years as the performance of copiers and printers has improved, and it has been attempted to obtain such high-performance color toners. However, for example, in the case of fine dispersion of the colorant, wetting of the colorant, and dispersion of other internal additives, a satisfactory color toner cannot always be obtained by the above-described conventional process. These insufficient color toners such as dispersion and wetting cause a reduction in image density, a decrease in transmittance, and a decrease in other performances.

[0013]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for producing a color toner in which the above-mentioned disadvantages have been improved. That is, an object of the present invention is to provide a method for producing a color toner in which at least a colorant is contained in a binder resin. Another object of the present invention is to provide a method for producing a color toner having a high coloring power, a sharp color tone, and a high transparency, which is uniformly dispersed in the toner. It is an object of the present invention to provide a production method for efficiently producing a high-quality color toner using a continuous processing kneading method which does not require any skill and does not require any repeated batch operation.

[0014]

The present invention provides a first kneading step in which a raw material mixture containing at least a binder resin and a colorant is melt-kneaded, and a kneaded product obtained in the first kneading step. A method for producing a color toner by pulverizing the kneaded product obtained in the second kneading step by diluting and mixing at least the same or different kinds of binder resins and melt-kneading the diluted mixture. In the first kneading step, a continuous type 2
A method for producing a color toner, wherein the roll-type kneader is used, the average residence time of the kneaded material in the kneader is at least 2 minutes, and an extruder is used in the second kneading step.

That is, raw materials containing at least a binder resin and a colorant are mixed in a container rotary mixer such as a W cone or V blender or a high-speed stirring mixer such as a Henschel mixer shown in FIG. The resulting mixture is
Kneading is performed in a first kneading step shown in FIG. That is, a continuous two-roll type kneader having two cylindrical rotating shafts 3 and 4 rotating inward each other in a cylindrical shape having a spiral groove on the surface as shown in FIG. The mixture is quantitatively and continuously supplied to the raw material supply unit 1 using a screw feeder or the like, and is kneaded.

Each of the rotary shafts of the continuous two-roll type kneader has a hollow inside, and is supplied with a heating medium such as steam or hot water or a cooling medium such as cooling water to supply each roll. The structure allows the surface temperature to be controlled arbitrarily. It is more preferable that the roll surface temperature on the raw material supply side of each roll and the roll surface temperature on the kneaded material discharge side be different from each other.

The mixture supplied to the raw material supply unit 1 is heated by the heat transfer effect on the roll surface by the heat medium supplied to the hollow portion inside the roll, and at the same time, rapidly rotates in the gap between the rolls as the roll rotates. The roll is melted while being heated by the application of a strong compressive force and shear force, and is transferred to the kneaded material discharge unit 2 at the other end of the roll while being kneaded by being repeatedly compressed and sheared in the gap between the rolls while being adhered to the roll surface. You.
The kneaded material is transferred because the raw material is continuously supplied and the raw material staying between the rolls in the raw material supply unit 1 is always larger than the other parts, that is, the bank formed between the rolls ( The raw material supply section has the largest amount of kneaded material
A pressure difference is generated in the axial direction to be a driving force, and furthermore, it is due to a screw effect generated by a linear groove provided on the roll surface. In this way, the kneaded material is continuously discharged from the kneaded material discharge portion while the colorant and the like are dispersed sufficiently uniformly while being continuously compressed and sheared between the rolls. Further, in order to continuously discharge the kneaded material, it is necessary to attach the kneaded material in the vicinity of the discharge portion to the front roll 3 due to the structure of the kneading machine. The rotation speed is equal to or higher than the rotation speed of the back roll 4, or
Regarding the temperature of each roll on the discharge side, it is important that the temperature of the front roll 3 is equal to or higher than that of the back roll 4. Also, on the raw material supply side, a heating medium is often used to efficiently melt the raw material, but once the molten raw material is melted, it generates heat due to the compressive and shearing forces acting repeatedly, resulting in a decrease in viscosity. Compressive and shear forces tend not to be efficiently given. However, the inside of the roll of the continuous two-roll kneader is of a two-split type, and the kneaded material is cooled by supplying a coolant such as cooling water to the inside of the discharge side of the roll to lower the viscosity of the kneaded material. And efficient kneading is possible. Particularly when a binder resin having a low melt viscosity and a sharp melt property is used, the effect is large. Thus, the continuous two-roll kneader used in the first kneading step is
Continuous feeding and continuous discharging can be performed without the repetitive pass (batch) operation as in the present roll mill. Furthermore, the kneading operation does not require an operation technique requiring skill based on empirical feeling. By setting the roll heating / cooling temperature, the number of rotations of each roll, the roll gap, and the like, a kneaded product of stable quality can be continuously obtained at all times, and the reliability is high enough to enable unmanned operation.

Hereinafter, the operating conditions of the continuous two-roll kneader will be described in more detail.

The rotation speed of each roll is preferably 150 rpm or less, and more preferably 100 rpm or less, in order to prevent extreme heat generation. The higher the number of roll rotations, the greater the compressive and shear forces applied to the kneaded material, but at the same time, the amount of heat generated also increases.If the cooling effect is not sufficient, it becomes difficult to control the temperature of the kneaded material, and the temperature of the kneaded material increases. In some cases, the viscosity of the kneaded material is reduced and sufficient shear is not applied, and the dispersion state of the colorant in the binder resin may be insufficient.

In the rotation ratio of the rolls, the rotation ratio between the high rotation side roll and the low rotation side roll is from 1: 1 to 1: 1.
The ratio of 0.1 to 0.1 is good, but within the range of 1: 0.4 to 1: 0.85, the power for rotating the roll can be made more efficient, and the dispersibility of the colorant can be improved. In addition, as the roll gap becomes narrower, the compressive force and shearing force applied to the kneaded material increase, but the calorific value also increases.If sufficient cooling is not performed, the temperature of the kneaded material increases, and the kneaded material increases. The viscosity is reduced, so that a sufficient compressive force and shear force cannot be applied to the kneaded material, and not only the dispersion state of the colorant in the binder resin becomes insufficient, but also the kneaded material passing through the roll gap. Since the amount of passage per unit roll length also decreases, productivity may be adversely affected. Therefore, the roll gap is preferably in the range of 0.3 mm to 3 mm. The average residence time of the kneaded material is determined by factors such as the roll outer diameter, the roll gap, the effective roll length, the kneaded material processing speed, and the kneaded material density, but in order to uniformly disperse the colorant in the binder resin. Requires an average residence time of at least 2 minutes, more preferably 5 minutes or more. The definition of the average residence time is given by the following equation: θ = 300 · π · L · ρ · Δd · (Δd + D) · 1 / F where θ: average residence time [min] L: effective roll length [m] D : Roll outer diameter [m] Δd: Roll gap [m] F: Kneaded material processing speed [kg / H] ρ: Kneaded material density [kg / m ³ ] π: Pi

The kneaded product thus obtained is cooled and crushed, and then at least additives of the same or different types of binder resin and a charge control agent are added thereto. After being diluted and mixed by a high-speed stirring type mixer such as a rotary mixer or a Henschel mixer, dilution and kneading are performed in a second kneading process using a continuous kneader such as an extruder, The obtained kneaded material is cooled if necessary, pulverized by a jet mill, then classified, cut into coarse and fine powders, and optionally subjected to an external addition step to obtain a color toner.

In the color toner, since the colorant is more uniformly dispersed in the binder resin, the coloring power is increased, a higher density can be secured as compared with the conventional color toner, and the color toner has higher transparency.

On the other hand, as the binder resin to be applied to the color toner of the present invention, all known resins can be used, and for example, styrene such as polystyrene, poly p-chlorostyrene, polyvinyltoluene and the like can be used. Polymer, styrene-p-chlorostyrene copolymer, styrene-propylene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-methyl acrylate copolymer, styrene-ethyl acrylate Copolymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, styrene -Α-chloromethyl methacrylate copolymer, styrene-acryl Nitrile copolymer, styrene -
Vinyl methyl ether copolymer, styrene-vinyl ethyl ether copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile-indene copolymer, styrene- Styrene copolymers such as maleic acid copolymer, styrene-maleic acid ester copolymer, polymethyl methacrylate, polybutyl methacrylate, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, polyester, polyurethane, polyamide, epoxy resin , Polyvinyl butyral, polyamide, polyacrylic acid resin, rosin, modified rosin,
Terpene resins, phenolic resins, aliphatic or alicyclic hydrocarbon resins, aromatic petroleum resins, chlorinated paraffins, paraffin waxes and the like can be used alone or in combination.

In particular, the effect of the present invention is great for a resin having a melt viscosity of 5 × 10 ⁵ poise or less at 100 ° C., preferably 1 × 10 ⁵ poise or less.

The method for measuring the melt viscosity is as follows. [Melt Viscosity Measurement Method] A flow tester CFT-500 type (manufactured by Shimadzu Corporation) is used. A sample weighs about 1.0 to 1.5 g of a 60 mesh pass product. This is pressurized with a load of 100 kg / cm ² for 1 minute using a molding machine. This pressurized sample was subjected to the following conditions under normal temperature and normal humidity (temperature about 20
-30 ° C., humidity 30-70% RH) to obtain a humidity-apparent viscosity curve. From the obtained smooth curve, an apparent viscosity at 100 ° C. is determined and defined as a melt viscosity with respect to the temperature of the sample.

RATE TEMP 6.0 D / M (° C./1 minute) SET TEMP 70.0 DEG (° C.) MAX TEMP 200.0 DEG INTERVAL 3.0 DEG PREHEAT 300.0 SEC (sec) LOAD 20.0 KGF (Kg) DIE (DIA) 1.0 MM (mm) DIE (LENG) 1.0 MM PLUNGER 1.0 CM ² (cm ² ) Also, any known coloring agent can be used.

For example, black colorants such as carbon black, acetylene black, lamp black, graphite, iron black, aniline black, cyanine black, graphite, cadmium yellow, yellow iron oxide, titanium yellow, naphthol yellow, hansa yellow, and pigment yellow , Benzidine Yellow, Permanent Yellow, Quinoline Yellow Lake, Anthrapyrimidine Yellow, etc., Yellow Colorants, Permanent Orange, Vulcan Fast Orange, Benzidine Orange, Indanthrene Brilliant Orange, etc. Orange Colorants, Iron Oxide, Amber, Permanent Brown, etc. Brown colorant, red bean, antimony powder, permanent red, fire red, brilliant carmine, light fast red toner, permanent carmine, pyrazolone red , Bordeaux, Helio Bordeaux, Rhodamine lake, Thioindigo red, Thioindigo maroon, etc., red colorant such as cobalt purple, fast violet, dioxazine violet, etc., cobalt blue, cerulean blue, metal-free phthalocyanine blue, phthalocyanine blue , Green colorants such as chrome green, cobalt green, green gold, phthalocyanine green, and polychrome bromide copper phthalocyanine. Particularly preferred are carbon black, C.I. I. Pigment Yellow 17, C.I. I. Pigment Yellow 1
5, C.I. I. Pigment Yellow 13, C.I. I. Pigment Yellow 14, C.I. I. Pigment Yellow 12,
C. 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 122, C.I. I. Pigment Red 20
2, C.I. I. Solvent Red 49, C.I. I. Solvent Red 52, C.I. I. Solvent Red 109, C.I.
I. Basic Red 12, C.I. I. Basic Red 1, C.I. I. Basic Red 3b, C.I. I. Pigment Blue 15, C.I. I. Pigment Blue 16 or a copper phthalocyanine pigment having a structural formula (1) shown below, which is a Ba salt in which a phthalocyanine skeleton is substituted with two or three carboxybenzamide methyl groups.

[0028]

Embedded image

[0029]

The present invention will be described in detail with reference to examples.

The color toner formulation used in this example is shown below.

(Formulation) (1) First kneading step formulation Unsaturated polyester resin 60 parts by weight Copper phthalocyanine pigment 40 parts by weight (CI Pigment Blue 15) (2) Second kneading step formulation Unsaturated polyester resin 100 parts by weight 12 parts by weight of the high-concentration colorant-containing resin crushed product obtained in (1) 4 parts by weight Charge control agent (chromium salicylate complex) 4 parts by weight 10 kg of a raw material weighed in the proportion of Example 1 formulation (1) was mixed with a Henschel mixer. Blade speed 700rpm, processing time 3
The mixture was mixed under the conditions of min., and the resulting mixture was quantitatively supplied to a continuous two-roll kneader shown in FIG. 1 by a table feeder and kneaded to obtain a high-concentration colorant-containing resin.

The continuous two-roll kneader has a roll outer diameter of 0.12 m and an effective roll length of 0.8 m, and the operating conditions are as follows.

High rotation side roll (front roll) rotation speed: 50 rpm Roll rotation ratio: 1: 0.8 Roll gap: 0.5 mm Heating / cooling medium temperature in roll High rotation roll: Raw material input side 60 ° C, kneaded material discharge side 45 ° C. Low rotating roll: 38 ° C. on the raw material input side, 32 ° C. on the kneaded material discharge side Supply rate of the raw material mixture: 5 kg / hour Average residence time of the kneaded material: about 9 minutes The kneaded material of the high concentration colorant-containing resin obtained is After cooling, the mixture was crushed with a hammer-type crusher using a 2 m / m screen, 10 kg of the formulation (2) was weighed, and the blade rotation speed was 850 rpm and the treatment time was 2 min with a Henschel mixer. To obtain a raw material for the second kneading step.

As a kneader in the second kneading step, an extruder (Ikegai Iron Works PCM-30) was used. The operating conditions are
Cylinder set temperature 100 ° C, barrel rotation speed 300rpm
m, and the raw material supply rate was 20 kg / H. After cooling the obtained toner kneaded material with a cooling belt, it was coarsely pulverized with a speed mill having a φ2 mm screen. After the crushed material was dissolved in xylene to adjust the viscosity, a coating film was formed on an OHP sheet using an electric film applicator using a bar coater so that the film thickness became 7 μm. Observation of the coating with an optical microscope showed that no coarse pigment mass was observed. Next, this crushed product was pulverized by an I-type jet mill, and fine powder and coarse powder were further cut by an elbow jet classifier to obtain a toner having an average particle size (D4) of 8.3 μm.

The average particle size is determined by using a Coulter counter (TA
-II). Furthermore, colloidal silica 0.6w
After externally adding t%, the mixture was mixed with a resin-coated iron powder carrier to obtain a developer.

Example 2 A mixture obtained under the same processing conditions as in Example 1 using the same formulation (1) as in Example 1 using a Henschel mixer was prepared.
Kneading was carried out using the continuous two-roll kneader. The operating conditions are as follows.

Roll rotation speed on high rotation side: 100 rpm Roll rotation ratio: 1: 0.6 Roll gap: 0.3 mm Heating / cooling medium temperature in roll High rotation roll: 50 ° C. on raw material input side, 38 ° C. on kneaded material discharge side Low rotation Roll: 30 ° C. on the material input side, 28 ° C. on the kneaded material discharge side Supply rate of the raw material mixture: 4 kg / hour Average residence time of the kneaded material: about 7 minutes The kneaded material of the high-concentration colorant-containing resin obtained was obtained in Example 1. After crushing in the same manner as in Example 1, a binder resin and a charge control agent are added under the same prescription and processing conditions as in Example 1, and dilution mixing and dilution kneading are performed to obtain a toner kneaded product. Coarse pulverization was performed with a mill.

This crushed product was obtained in the same manner as in Example 1.
When a coated film was formed on an OHP sheet and the coated film was observed with an optical microscope, a coarse pigment mass was hardly observed.

Next, this crushed product was pulverized, classified, externally added, and mixed with a carrier under the same conditions as in Example 1 to obtain a developer.

Example 3 A mixture obtained under the same conditions as in Example 1 under the same processing conditions as in Example 1 using a Henschel mixer was kneaded using the continuous two-roll kneader. The operating conditions are as follows.

Roll rotation speed on high rotation side: 100 rpm Roll rotation ratio: 1: 0.6 Roll gap: 0.3 mm Heating / cooling medium temperature in roll High rotation roll: 60 ° C. on raw material input side, 45 ° C. on kneaded material discharge side Low rotation Roll: 38 ° C. on the raw material input side, 32 ° C. on the kneaded material discharge side Feed rate of the raw material mixture: 14 kg / hour Average residence time of the kneaded material: about 2 minutes The obtained high-concentration colorant-containing resin is the same as in Example 1. The mixture was diluted and kneaded, cooled, and crushed. This crushed material was coated on an OHP sheet in the same manner as in Example 1, and the coated material was observed with an optical microscope. As a result, almost no coarse pigment mass was found.

The raw material 10 which is metered in the same formulation as Comparative Example 1 (1)
kg with a Henschel mixer 700 rpm
The mixture was mixed under the conditions of m and processing time of 3 min, and 0.5 kg of the obtained mixture was put into the raw material supply section of the three-roll mill shown in FIG. The kneaded material was discharged. Since the kneaded product did not sufficiently disperse the pigment, the same kneading operation was repeated a total of four times to obtain a high-concentration colorant-containing resin. This operation was performed several times to obtain a total of 3 kg of the kneaded material.

The three-roll mill has a roll outer diameter of 0.05
1m, effective roll length 0.152m, supply roll rotation speed 7
At 0 rpm, the roll rotation ratio was 1.5 to 2.5 for the central roll and the apron roll with respect to the supply roll 1, the roll gap was 0.5 mm, and the roll temperature was 60 ° C.
The obtained kneaded product and crushed product were weighed at the ratio of the prescription (2), diluted and mixed and kneaded under the same conditions as in Example 1, and after cooling the obtained kneaded toner, a screen having a diameter of 2 mm was provided. It was coarsely pulverized by a speed mill. This crushed product was coated on an OHP sheet in the same manner as in Example 1, and the coated product was observed with an optical microscope. As a result, coarse pigment clumps were found in some places. Next, this crushed product was pulverized by an I-type jet mill, and fine powder and coarse powder were further cut by an elbow jet classifier to obtain a toner having an average particle diameter of 8.3 μm. The average particle size is measured using a Coulter counter (T
A-II). Furthermore, colloidal silica 0.6
After externally adding wt%, it was mixed with a resin-coated iron powder carrier to obtain a developer.

(Image Deposition of Examples 1, 2, 3 and Comparative Example 1) Coloring power and transmission of toner when images of the respective developers of Examples 1, 2, 3 and Comparative Example 1 were formed. Sex was confirmed.

The image was formed using a color laser copier 500 (CLC-500) manufactured by Canon Inc. OHP
Using a sheet, the amount of toner on the sheet is 0.5 mg /
A solid image was taken so as to give a cm ² , fixed at a temperature of 160 ° C., and the difference in image density was observed with a Macbeth reflection densitometer. Further, the difference in the transparency of the image was observed with a HAZE meter. As a result, the average image density was 1.18 for the developer of Example 1, 1.13 for the developer of Example 2, and 1.07 for the developer of Example 3, whereas the average of the image density was 1.07 for the developer of Example 3. The value of the developer was only 1.02.

Regarding the transparency of the image, the average of the HAZE values was 18.3 in the developer of Example 1, 18.6 in the developer of Example 2, and 19.0 in Example 3. On the other hand, the developer of Comparative Example 1 had a transparency of 21.0, which was inferior to the Example.

Next, each image was projected on a white screen by an overhead projector, and the images of Examples 1, 2, and 3 were compared with those of Comparative Example 1. The images of Examples 1, 2, and 3 were clear and vivid. Although the image was a very blue (cyan) color, the image of Comparative Example 1 was slightly dull and yellowish.

The HAZE value is represented by the following equation: HAZE value = diffuse transmittance / total transmittance. The better the dispersion of the colorant, the lower the diffuse transmittance, and therefore the smaller the HAZE value. The HAZ meter used for measuring the HAZ value is NDH-1001DP type manufactured by Nippon Denshoku Industries Co., Ltd.

[0049]

As described above, conventionally, in kneading a resin containing a high-concentration colorant, a high level of skill, which has been used for a long time, is required for the operation, and the batch operation must be repeated several times. The production method using the color toner production method of the present invention eliminates the need for empirical high-level skills, and enables continuous processing and unmanned operation. A color toner having excellent transparency due to its coloring power can be manufactured.

[Brief description of the drawings]

FIG. 1 shows a continuous two-roll kneading apparatus used in a first kneading step in carrying out the present invention.

FIG. 2 is a view showing a process of manufacturing a cyan toner according to the present invention and a conventional example.

FIG. 3 shows three rolls used in a comparative example.

FIG. 4 shows an example of a high-speed stirring type mixer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Raw material supply part 2 Kneaded material discharge part 3 Front roll 4 Back roll 5 Heating and cooling medium supply and discharge part 6 Heating and cooling medium supply and discharge part 7 Roll drive motor 8 Roll drive motor 11 Supply roll 12 Central roll 13 Apron roll 14 Raw material supply unit 15 Kneaded material discharge unit 16 Discharge scraper 17 Heating / cooling medium supply / discharge unit 18 Roll gap adjustment handle 19 Roll gap adjustment handle 20 Roll drive motor

──────────────────────────────────────────────────続 き Continuation of front page (72) Inventor Kazuyuki Miyano 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (56) References JP-A-62-30259 (JP, A) JP-A-62 JP-A-3-164750 (JP, A) JP-A-1-142559 (JP, A) JP-A-4-309996 (JP, A) JP-B-3-47131 (JP, B2) ) "Polymer Digest March 1991" (March 15, 1991) Rubber Digest Co. p. 121-122 (58) Field surveyed (Int. Cl. ⁷ , DB name) G03G 9/08

Claims (5)

(57) [Claims] 1. A first kneading step in which a raw material mixture containing at least a binder resin and a colorant is melt-kneaded, and a kneaded product obtained in the first kneading step is made of at least the same or different binder resin. A second kneading step of diluting and mixing, and melt-kneading the diluted mixture, wherein the kneaded material obtained in the second kneading step is pulverized to produce a color toner; using a roll-type kneader state, and are the mean residence time of at least 2 minutes or more of the kneaded material in the kneading machine, the method for producing a color toner, which comprises using an extruder in the second kneading step. 2. The method for producing a color toner according to claim 1, wherein the number of rotations of a rotating roll of the kneading machine used in the first kneading step is 150 rpm or less. 3. The method according to claim 1, wherein the rotation ratio of each rotating roll of the kneading machine used in the first kneading step is in a range of 1: 1 to 1: 0.1. A method for producing a color toner. 4. In the second kneading step, the first kneading step
Mix the kneaded material obtained in the above with the charge control agent and melt-knead
4. A camera according to claim 1, wherein
Manufacturing method of Lartner. 5. A continuous two-roller used in a first kneading step.
The set temperature of the screw-type kneader is used in the second kneading step.
It is lower than the set temperature of the extruder
The color toner according to claim 1, wherein
Manufacturing method.