JPH0611895A - Production of color toner - Google Patents

Abstract

PURPOSE:To provide a production method for color toner improved in the dispersibility and wettability of a coloring agent, capable of obtaining the excel lent color toner small in the change of ratio of each component even at the time of atomizing by pulverization, finely dispersed, high in coloring ability, bright in tone and high in transmissivity and using a contituous kneading method in which repeating batch operation demading skill is completely unnecessary. CONSTITUTION:A granulated material or a mixture obtained by granulating a raw material mixture in a 1st kneading process or by using a dry type dispersing machine by the use of a medium to mix the raw material in the 1st kneading process is molten and kneaded by a continuous double roll type kneader and the average retension time of the material to be kneaded is >=2min.

Description

Detailed Description of the Invention

[0001]

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

[0002]

In electrophotography, generally, a photoconductive substance is used to form an electrical latent image on a photoreceptor by various methods, and then the latent image is developed with a toner. ,
A method is available in which a toner image is transferred to a transfer material such as paper, if necessary, and then fixed by various methods to obtain a copy. The toner used at this time is generally classified into a dry toner and a wet toner, but due to problems such as volatilization, recovery and odor of the solvent used in the wet toner,
In recent years, dry toner has become the mainstream. Further, the toner is a powder that forms an image, but it is necessary that the toner particles have many functions in order to form an image accurately. For example, the charging property, the transport property, the fixing property, the coloring power, the storage property, and the like. Therefore, the toner is prepared as a mixture of various raw materials.

As a method for producing a dry toner, a pulverization method,
A polymerization method, an encapsulation method and the like can be mentioned, but generally, a pulverization method occupies the mainstream. As a general method for producing a color toner by a pulverization method, first, a binder resin for fixing to a transfer material, various colorants for producing a tint as a color toner, and a charge control agent are required. Raw materials consisting of other additives that are added according to dry mixing, and then melted mainly by compressive force and shearing force while applying temperature with a general-purpose kneading device such as a kneader, roll mill, or extruder. After kneading and cooling and solidification, coarse pulverization is performed as necessary to produce a kneaded and coarsely pulverized product, and then fine pulverization is performed using a fine pulverization device such as a jet mill to an appropriate particle size as a color toner. Thereafter, if necessary, classification is carried out by various classifiers so that 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, etc. are dry-mixed and used as a color toner. When it is used as a so-called two-component toner, it is mixed with various magnetic carriers and then used as a developer for image formation.

Factors relating to the performance of color toners are tinting strength and transparency. The tinting strength and the transparency depend on the amount of the colorant, but also largely depend on the dispersion of the colorant. The dispersion state of various raw materials in the color toner particles in the color toner is substantially determined by the step of mixing the raw materials and the step of kneading the raw materials in the method for producing the color toner by the pulverization method. As a manufacturing device used for mixing raw materials, a container rotary type mixer such as a V blender or a W cone, or a high-speed stirring type mixing device such as a Henschel mixer is usually used, and a mixture prepared by these devices is used. Is melt-kneaded by a kneader or an extruder. However, the kneaded product obtained by the method for producing a color toner by the pulverization method is inferior in coloring power and transparency as a color toner because the dispersed state of the colorant in the binder resin is insufficient.

Therefore, a manufacturing method made to partially improve these problems has the first kneading step and the second kneading step shown in the manufacturing process diagrams of the conventional example of FIGS. 3 and 9. It is a manufacturing method. That is, in the first kneading step, a high-concentration colorant-containing resin containing a colorant at least the content ratio of the colorant of the kneaded product obtained in the second kneading step is kneaded, and further in the second kneading step, Add additives such as a binder resin and a charge control agent according to the conditions, dilute and mix, and then knead using a kneader such as a kneader or an extruder.
A kneaded product of color toner is obtained. However,
In the above-mentioned manufacturing method, as the mixer used in the raw material mixing step of the first kneading step, a container rotary type mixer such as a V blender or a W cone, or a high speed stirring type mixing type mixing device such as a Henschel mixer is used. Since the raw materials are used, they cannot be dispersed microscopically, and even if the mixing and kneading conditions are devised, it is often impossible to obtain sufficiently satisfactory dispersion or wettability of the raw materials. Furthermore, when focusing on the particle size of the raw material, in general, it is true that the smaller the raw material particle size, the better the dispersion or wetting, but in reality, when the particle size is made smaller, the cohesive force of the raw material particles becomes stronger. However, sufficient dispersion cannot be obtained during premixing. or,
The finer the particles, the more likely they are to contain air, and sufficient kneading dispersion cannot be obtained.

A typical kneading machine used in the first kneading step is a three-roll mill, but the kneading operation of such a kneading machine is a batch operation, and various kneading conditions, that is, kneading temperature and rolls are used. While the conditions such as rotation speed, clearance between rolls, rotation ratio of each roll, and the number of passes (the number of passes) are subtly changed, the worker performs kneading thoroughly, and the dispersion state of the colorant in the kneaded product is performed. This is a process that requires a great deal of skill in order to control the temperature evenly.
Further, in regard to the number of passes, it is necessary to perform batch processing at least 2 times or more, preferably 4 times or more, and since work is performed by human means each time, there is concern about the structural safety of the machine. This is the accompanying manufacturing method.
Further, in terms of toner quality, the performance required for color toner itself has become more severe in recent years as the performance of copying machines and printers has improved. However, in the above-described conventional manufacturing method, for example, it is often not always possible to obtain a satisfactory color toner in fine dispersion of the colorant, wetting of the colorant, dispersion of other internal additives, and the like. These color toners that are insufficiently dispersed or wetted result in a decrease in image density, a decrease in transmittance, and a decrease in other properties of the obtained image.

[0007]

OBJECTS OF THE INVENTION Accordingly, the object of the present invention is to solve the above-mentioned problems of the prior art, improve the dispersibility of colorants and the like, and provide a manufacturing method for producing a higher performance color toner. To do. To describe the object of the present invention in more detail,
Provided is a method for producing a color toner in which the dispersibility of a colorant and other internal additives is improved. That is, the object of the present invention is to improve the dispersion and wetting of the colorant, and even if the particles are atomized by pulverization, the change in the ratio of each component is small, and the particles are finely dispersed, the coloring power is high, and the color tone is high. The present invention provides a method for producing a color toner capable of obtaining an excellent color toner having high clear transparency. Another object of the present invention is to provide a method for producing a color toner in which internal additives are less liberated by pulverization and contamination of a developing sleeve, a carrier and the like is less likely to occur. A further object of the present invention is to provide a method for producing a color toner having no material bias, good developability and durability, no fog, and good environmental characteristics. Still another object of the present invention is to use a kneading method of continuous treatment, which is mainly a human work, does not require skill depending on experience and intuition of an operator, and does not require repeated batch operation at all. Provided is a method for producing a color toner, which can efficiently produce a high quality color toner.

[0008]

The above objects can be achieved by the present invention described below. That is, the first invention of the present invention, at least, a first kneading step of melt kneading a raw material mixture containing a binder resin and a colorant in a kneader, and the kneaded product obtained in the first kneading step A second kneading step of diluting and mixing with at least the same kind or different kinds of binder resins, and further melt-kneading the diluted mixture, and pulverizing the kneaded material obtained in the second kneading step to produce a color toner In the method for producing a color toner, the raw material mixture is granulated in the first kneading step, the obtained granulated product is melt-kneaded using a continuous two-roll type kneader, and the kneaded product in the kneader is used. The method for producing a color toner is characterized in that the average residence time of at least 2 minutes is at least 2 minutes, and the second invention of the present invention is to mix at least a binder resin and a colorant and to prepare the raw material mixture. The first kneading step of melting and kneading with a kneader The kneaded material obtained in the first kneading step is diluted and mixed with at least the same or different binder resins, and the second kneading step of melting and kneading the diluted mixture is further included, and obtained in the second kneading step. In a method for producing a color toner by pulverizing the kneaded product to produce a color toner, a dry type disperser using a medium is used for mixing the raw materials in the first kneading step, and a continuous two-roll type is used for kneading the raw material mixture. The method for producing a color toner is characterized in that a kneader is used and an average residence time of the kneaded product in the kneader is at least 2 minutes or more.

[0009]

The present inventors have conducted extensive studies to solve the problems of the prior art, and as a result, in the conventional method for producing a color toner having the first kneading step and the second kneading step, the raw material of the first kneading step is used. Kneading used in the first kneading step of granulating the mixture, more preferably at least 1.1 times the bulk density of the raw material mixture, and melt-kneading the obtained granulated product. Completed the first invention of the present invention by finding that if the apparatus is not a conventional three-roll mill or the like but a continuous two-roll type kneader, it is possible to improve the wettability of the coloring agent in particular. did. Further, in the conventional method for producing a color toner having a first kneading step and a second kneading step, in the mixing of the raw materials in the first kneading step, a dry dispersing machine having a strong shearing force, not a conventional mixing device, In particular, if a kneading device used for kneading the raw material mixture using a dry disperser using a medium is a continuous two-roll kneader instead of a conventional three-roll mill, the above-mentioned invention Similar to the first invention, the inventors have found that the wettability of the colorant can be improved, and have completed the second invention of the present invention.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The first invention of the present invention will be described in more detail with reference to the accompanying drawings with reference to the preferred embodiments. FIG. 1 shows an example of a mixing granulator used in the raw material mixing step and the granulation step of the first kneading step used in the method of the present invention. An example of a continuous two-roll type kneader used for kneading in the first kneading step is shown in FIG. Hereinafter, these will be described in detail. In the mixing granulator of FIG. 1, 1
Is a body casing, 2 is a jacket, 3 is a body cover,
Reference numeral 4 is a main blade, and 5 is a granulation blade. In this apparatus, the main blade 4 and the granulating blade 5 rotate at high speed, and by the mixing action mainly including the shearing action, sufficient mixing is performed in a short time while crushing the aggregates of the object to be treated. Further, the temperature of the object to be treated rises due to the shear heat generated during stirring (mainly generated by the rotation of the main blade 4), the components of the object to be treated are partially softened, and the object to be treated is granulated. is there. The granulation blade 5 has a granulation effect as well as a granulation effect.

The raw material charged into the mixing and granulating machine as shown in FIG. 1 is decomposed into a raw material aggregate such as a coloring agent by the mixing action mainly based on the shearing action by the high speed rotary motion of the main blade 4 and the granulating blade 5. Mixed while being crushed. Furthermore, the temperature of the mixture gradually rises during the mixing operation due to the shear heat generated during mixing, and a part of the mixture begins to soften, and the mixture is granulated with this as a core. In the mixing and granulating machine as shown in FIG. 1, the operating conditions such as the shape of the main blade, the shape of the granulating blade, the number of rotations of the blade, and the processing time are more suitable depending on the raw materials used and the desired mixed state and granulated state. You just have to set it. Further, it is more preferable to control the temperature of the mixed granulated product by providing the main body casing 1 with a jacket structure and supplying a heat medium or a refrigerant in terms of shortening the granulation time and measures against adhesion.

The step of mixing the raw materials and the step of granulating in the first kneading step of the present invention are equipments with separated functions such that mixing and granulation are carried out by different equipments, for example, a container rotary mixer. Alternatively, the obtained mixture may be granulated by a roller compression granulator. Further, the mixer and granulator used in the first kneading step of the present invention are not limited to these types, and any type of mixer and granulator can be used. The bulk density of the granulated product obtained in the first kneading step of the present invention is preferably 1.1 times or more, more preferably 1.3 times or more the bulk density of the raw material mixture. The bulk density of the raw material mixture and the granulated product was measured with a powder tester (manufactured by Hosokawa Micron).

Next, the granulated product obtained in the mixing and granulating step of the first kneading step is kneaded in the kneading step of the first kneading step. In the method of the present invention, a continuous two-roll type kneader is used as the kneader used at this time. As illustrated in FIG. 2, the continuous two-roll type kneader has two cylindrical rotary shafts 13 each having a plurality of grooves in a linear shape on its surface and rotating inward with respect to each other. And 14. 13 is a front roll and 14 is a back roll. In the continuous two-roll type kneading machine, kneading is performed while quantitatively and continuously supplying the granulated material to the raw material supply section 11 shown in FIG. 1 using a screw feeder or the like. The inside of each of the roll rotating shafts 13 and 14 of the continuous two-roll type kneader is hollow, and the surface of each roll is supplied by supplying a heat medium such as steam or warm water, or a refrigerant such as cooling water. It has a structure in which the temperature can be controlled arbitrarily. Further, it is more preferable that the roll surface temperature of the raw material supply side of each roll and the roll surface temperature of the kneaded material discharge side can be controlled to different temperatures.

The granulated material supplied to the raw material supply section 11 is heated by the heat transfer action on the surface of the roll by the heat medium filled in the hollow portion of the roll, and at the same time the roll 13 and the roll 13 are rotated. A rapid compressive force and a shearing force are applied in the gap between 14 to melt while generating heat, and repeatedly compressed in the roll gap while adhering to the roll surface,
While being sheared and kneaded, the raw material supply unit 11 of the roll
Is transferred to the kneaded material discharge section 12 side on the other end side opposite to the end section having. In the transfer of the kneaded material, since the raw material is continuously supplied from the raw material supply section 11, the raw material staying between the rolls 13 and 14 in the raw material supply section 11 is always larger than the other portions, that is, between the rolls. Since the amount of banks (retained product of kneaded material) formed in the raw material supply portion 11 is the largest, a pressure difference is generated in the axial direction, which serves as a driving force to transfer the kneaded material. Furthermore, the kneaded material is transferred by the screw effect generated by the linear grooves provided on the surface portions of the rolls 13 and 14.

When the raw material to be processed by the kneader as described above is in the form of granules, the wettability and bulk density of the raw materials are higher than those of the conventional raw material mixture of powders which are not granulated. The effect is to increase, to reduce the processing volume as a raw material supply amount, and to improve fluidity (especially flushing property). As a result, not only the biting property of the raw material between the rolls in the raw material supply unit 11 is improved, but it is effective in preventing the flushing of the untreated raw material between the rolls, and the piston flow property is improved. As described above, the kneaded material is continuously subjected to repeated compression and shearing force between the rolls, and the kneaded material is continuously and continuously discharged in a state where the colorant and the like are sufficiently uniformly dispersed.
More discharged.

In order to continuously discharge the kneaded material,
Due to the structure of the kneading machine, it is necessary to adhere the kneaded material in the vicinity of the discharge part 12 to the front roll 13, and for this purpose, the rotation speed of the front roll 13 is set to the back roll 14.
It is important that the rotation speed is equal to or higher than the rotation speed of No. 1 or the temperature of the front roll 13 is equal to or higher than that of the back roll 14 for each roll temperature on the discharge side. Further, on the raw material supply side 11, a heat medium is often used to efficiently melt the raw material, but once the molten raw material is melted, heat is generated by the compressive force and the shearing force that repeatedly act, and the viscosity of the raw material lowers. As a result, the compression force and the shearing force tend not to be efficiently applied. However, the inside of the roll of the continuous two-roll type kneader used in the present invention is a two-part type, and therefore the kneaded product is cooled by supplying a coolant such as cooling water into the discharge side of the roll. It is possible to suppress the decrease in viscosity of the kneaded product, and it is possible to carry out efficient kneading. In particular, the effect is great when a binder resin having a low melt viscosity and a sharp melt property is used.

As described above, the continuous two-roll type kneader used in the first kneading step of the method of the present invention does not require the repeated pass (batch) operation unlike the conventional three-roll mill, It is possible to continuously supply and discharge raw materials. Further, on the kneading work, without requiring a skilled operation method based on the empirical intuition of the operator, the initial conditions of the operation, namely, the kneading speed, the heating and cooling temperatures of the rolls, the rotation speed of each roll and By setting the roll gap etc.,
The kneaded material of stable quality is continuously obtained, and the reliability is high enough to allow unmanned operation.

The preferred operating conditions of the continuous two-roll type kneader used in the method of the present invention will be described in more detail below. The rotation speed of each roll is preferably 150 rotations / minute or less, more preferably 100 rotations / minute or less, in order to prevent excessive heat generation. The higher the rotational speed of the roll, the greater the compressive force and shearing force applied to the kneaded product, but at the same time, the calorific value also increases, so if the cooling effect is not sufficient, it becomes difficult to control the temperature of the kneaded product, In some cases, the temperature rises, and as a result, the viscosity of the kneaded product decreases, sufficient shearing does not occur, and the colorant in the binder resin is insufficiently dispersed. Also, as the rotation ratio of each roll,
The rotation ratio of the high rotation side roll and the low rotation side roll is 1: 1 to 1
It is preferably in the range of 1: 0.1, but 1: 0.4
Within the range of from 1: 0.85, shearing force and compressing force are applied more effectively to the kneaded product, and the dispersion state of the colorant and the like becomes good.

Further, as the roll gap becomes narrower, the compressive force and the shearing force applied to the kneaded product increase, but the calorific value also increases, so that the temperature of the kneaded product increases if sufficient cooling is not performed. The viscosity of the kneaded product is reduced, and sufficient compression force and shearing force cannot be applied to the kneaded product, and not only the colorant in the binder resin is insufficiently dispersed,
Since the amount of the kneaded material passing through the roll gap per unit roll length is also reduced, it may have an adverse effect on the productivity.
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 outer diameter of the roll, roll gap, effective roll length, kneaded material processing speed, and kneaded material density. In order to disperse uniformly, an average residence time of at least 2 minutes is required, and 5 minutes or more is more preferable. The definition of the average residence time is shown below by an equation.

Θ _s = 300 · π · L · ρ · Δd · (Δd
+ D) · 1 / F Here, the respective symbols represent the following. θ _s : 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 obtained as described above is cooled and, if necessary, roughly crushed, and then in the second kneading step, at least the same kind or different kinds of binder resins and additives such as a charge control agent are added. After mixing, the mixture is diluted and kneaded with a kneader typified by an extruder, etc., and the resulting kneaded product is cooled and crushed if necessary, and crushed with a fine crusher such as a jet mill. After that, the toner is classified, coarsely crushed and fine powder is cut, and if necessary, an external addition step is performed to obtain a color toner. In the color toner thus obtained, the colorant is more evenly finely dispersed in the binder resin, so that the coloring power is increased and a higher concentration of the colorant can be secured as compared with the conventional one. , Higher transparency can be obtained.

As the binder resin for the color toner used in the present invention, all known binder resins can be used. For example, polystyrene, poly-p-chlorostyrene, homopolymers of styrene such as polyvinyltoluene and its substitution products, styrene-p-chlorostyrene copolymers, styrene-propylene copolymers, styrene-vinyltoluene copolymers, Styrene-vinyl naphthalene 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- Acrylonitrile copolymer, styrene-
Vinyl methyl ether copolymer, styrene-vinyl ethyl ether copolymer, styrene-vinyl ethyl ketone copolymer, styrene-butanediene copolymer, styrene-
Isoprene copolymer, styrene-acrylonitrile-indene copolymer, styrene-maleic acid copolymer, styrene-styrene copolymers such as 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 resin, phenol resin, aliphatic or alicyclic hydrocarbon resin, aromatic petroleum resin, chlorinated paraffin, paraffin wax 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 measuring method It is measured by the following operation using a flow tester CFT-500 type (manufactured by Shimadzu Corporation). About 1.0 to 1.5 g of the sample that has passed through the 60-mesh sieve is weighed. This is put into a molding machine and pressed under a load of 100 kg / cm ² for 1 minute to prepare a sample for measurement. Using the above flow tester, this pressurized sample is subjected to flow tester measurement under normal temperature and normal humidity (temperature of about 20 to 30 ° C., humidity of 30 to 70% RH) under the following conditions to obtain a humidity-apparent viscosity curve. From the obtained smooth curve, the apparent viscosity at 100 ° C. is calculated,
Let it be the 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 (° C) -INTERVAL 3.0 DEG (° C) -PREHEAT 300.0 SEC ( Seconds) ・ LOAD 20.0 KGF (kg) ・ DIE (DIA) 1.0 MM (mm) ・ DIE (LENG) 1.0 MM (mm) ・ PLUNGIR 1.0 CM ² (cm ² )

As the colorant for the color toner used in the present invention, all known colorants can be used. For example,
Black colorants such as carbon black, acetylene black, lamp black, graphite, iron black, aniline black, cyanine black, yellow lead, cadmium yellow, yellow iron oxide, titanium yellow, naphthol yellow, Hansa yellow,
Pigment Yellow, Benzidine Yellow, Permanent Yellow, Quinoline Yellow Lake, Anthracyrimidine Yellow, and other yellow colorants, permanent orange,
Balkan Fast Orange, Benzene Orange, Indanthrene Brilliant Orange and other orange colorants, Iron Oxide, Amber, Permanent Brown and other brown colorants,
Bengal, antimony powder, permanent red, fire red, brilliant carmine, light fast red toner, permanent carmine, pyrazolone ren red, bordeaux, helio bordeaux, rhodamine lake,
Red colorants such as thioindigo red, thioindigo maroon, purple colorants such as cobalt purple, fast violet, dioxazine violet, cobalt blue, cerulean blue, metal-free phthalocyanine blue, phthalocyanine blue, indanthrene blue, indigo, etc. There are green colorants such as blue colorants, chrome green, cobalt green, green gold, phthalocyanine green, polychrome copper phthalocyanine,

Particularly preferably, carbon black, C.I.
I. Pigment Yellow 17, C.I. I. Pigment Yellow 15, C.I. I. Pigment Yellow 13, C.I. I.
Pigment Yellow 14, C.I. I. Pigment Yellow 12, C.I. I. Pigment Red 5, C.I. I. Pigment Red 3, C.I. I. Pigment 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. Basic Red 12, C.I.
I. Basic Red 1, C.I. I. Basic red 3
b, C.I. I. Pigment Blue 15, C.I. I. Pigment Blue 16 or a copper phthalocyanine pigment which is a Ba salt in which the phthalocyanine skeleton has 2 to 3 carboxybenzamidomethylki groups and which has the structural formula (1) shown below.

[0027]

[Chemical 1]

Next, the second invention of the method of the present invention will be described. In the second invention of the present invention, as shown in the process diagram of FIG. 9, a dry dispersion machine having a strong shearing force is used instead of using a conventional mixing device in the step of mixing the raw materials in the first kneading step. In particular, it is characterized by mixing using a dry dispersion machine using a medium. FIG. 8 shows an example of a dry-type disperser using a medium used in the method of the present invention. Hereinafter, this will be described in detail. In FIG. 8, 71 is a main body container, 72 is an agitator shaft, 73 is an agitator arm, and 74 is a ball.

In this apparatus, the agitator arm 73 rotates at a high speed to move a plurality of balls 74 as media, and the shearing force, compressive force and impact force between these balls make the object to be treated more uniform. Distributed. That is, in the method of the present invention, first, a raw material containing at least a binder resin and a colorant is added to the dry dispersion machine as described above (FIG. 8).
And the binder resin and the colorant are mixed and dispersed more uniformly by the shearing force, the compressing force and the impact force between the media. Due to the repeated shearing action that occurs between these media,
In particular, a fine raw material such as a coloring agent having a strong cohesive property is sufficiently dispersed in the vicinity of the surface of the binder resin particles and is microscopically precisely mixed.

In the above dry dispersion machine, the material and diameter of the ball 74 as a medium, the rotation speed of the agitator arm 73, and the dispersion time may be appropriately set depending on the raw material used and the desired dispersion state. It is more preferable that the balls, agitator arm, and tank as media are made of ceramics having excellent wear resistance.
Further, it is more preferable that the tank has a jacket structure and that the tank is cooled by passing a cooling medium because heat generation can be suppressed. Further, in the step of mixing the raw materials in the first kneading step of the method of the present invention, if more uniform mixing and dispersion are desired, preliminary mixing may be carried out before such dry dispersion.

In the second invention method of the present invention, in the mixing step of the first kneading step, the mixture thus obtained is kneaded in the kneading step of the first kneading step. As the kneading machine used in this case, a continuous two-roll kneading machine is used as in the first invention method. The conditions used and the like are the same as in the first invention method. The raw materials such as the binder resin and the colorant used for the toner are also the same as in the first invention method.

The present invention will be described more specifically below with reference to Examples and Comparative Examples. Examples 1 to 4 relate to a method for producing a first color toner of the present invention,
Examples 5 to 8 relate to a method for producing the second color toner of the present invention. First, the formulation of the color toner used in the present invention is shown below. First kneading process formulation-Unsaturated polyester resin 60 parts by weight-Copper phthalocyanine pigment (CI Pigment Blue 15) 40 parts by weight Second kneading process formulation-Unsaturated polyester resin 100 parts by weight-High concentration obtained Crushed resin containing colorant 12 parts by weight Charge controllability (chromic salicylate complex) 4 parts by weight

Example 1 The materials having the above formulations were mixed and granulated by using the mixing / granulating apparatus shown in FIG. 1 as follows. The effective capacity was 62 liters. 3 kg of the above ingredients
Put into mixing / granulating equipment, main blade root rotation speed 400 rotations /
Min, mixing was performed for 3 minutes at a granulating blade rotation speed of 1450 rotations / minute. Further, after stirring was performed at a main blade rotation speed of 850 rotations / minute and a granulation blade rotation speed of 2950 rotations / minute until the mixture temperature reached 55 ° C., the main blade rotation speed was 150 rotations / minute,
Granulation was performed at a granulation blade rotation speed of 1450 rotations / minute.
Incidentally, cooling water was supplied to the jacket to control the temperature so that the temperature of the mixture could be maintained at 55 ° C. Further, when the load power of the main blade shows an increasing tendency, the main blade rotation speed is 7
Granules were obtained by operating at 00 rpm for 30 seconds. The bulk density of the granulated product thus obtained was about 1.6 times that of the raw material mixture (measured by powder tester).

The obtained granulated product was quantitatively supplied to the continuous two-roll type kneader shown in FIG. 2 by a table feeder and kneading was performed to obtain a high-concentration colorant-containing resin. The continuous two-roll type kneader used at this time had a roll outer diameter of 0.12 [m] and an effective roll length of 0.8 [m], and the operating conditions were high rotation side rolls (front rolls). )
The rotation speed was 50 rotations / minute, the roll rotation ratio was 1: 0.8, the roll gap was 0.0005 [m], and the heating and cooling medium temperatures in the roll were 60 ° C. on the raw material charging side of the high rotation roll and 45 on the kneaded material discharging side. C, and the low-roll roll material input side is 3
The temperature was 0 ° C. and the kneaded material discharge side was 30 ° C., the feed rate of the raw material mixture was 5 kg / hour, and the average residence time was about 9 minutes.

Next, the mixture of the high-concentration colorant-containing resin obtained as described above was cooled, and then roughly crushed with a hammer type crusher using a screen of 1 m / m, and then second kneading. The process was processed. That is, raw material 1 at the ratio of prescription
After weighing 0 kg and mixing with a high-speed stirring mixer under the conditions of a blade rotation speed of 850 rotations / minute and a processing time of 2 minutes,
Extruder (Ikegai Tekko PCM-3
Dilution and kneading were carried out at 0). Operating conditions are: barrel setting temperature 100 [° C], screw rotation speed 300 [revolution /
Min] and the raw material supply rate was 20 [kg / hr].

The obtained toner kneaded product was cooled with a cooling belt and then roughly crushed with a speed mill having a screen of φ2 [mm]. This coarsely crushed product was dissolved in xylene to adjust the viscosity, and then a coating film was formed on the OHP sheet by an electric film applicator using a bar coater so that the film thickness was about 7 μm. When this coated material was observed with an optical microscope, no coarse pigment lumps were observed.
Next, this coarsely pulverized product was pulverized by an I-type jet mill, and further, coarse powder and fine powder were cut by an elbow jet classifier to obtain a cyan toner having an average particle diameter (D4) of 8.3 [μm]. . The average particle size is measured by Coulter Counter (TA
-II). Further, 0.6 wt% of colloidal silica was externally added to this, and then mixed with a resin-coated iron powder carrier to obtain a developer.

Example 2 Using the same formulation as in Example 1 as a raw material and using the same mixing and granulating apparatus, mixing and granulation were carried out under the following conditions.
3 kg of the material of the above formulation was charged into the mixing / granulating apparatus, the main blade root rotation speed was 400 rotations / minute, and the granulation blade rotation speed was 1
Mixing was performed at 450 rpm for 3 minutes. Further, the main blade rotating speed was 700 rpm, the granulating blade rotating speed was 2950 rpm, and the operation was continued until just before the main blade load power suddenly increased. The operation was performed at a blade rotation speed of 100 rotations / minute and a granulation blade rotation speed of 1450 rotations / minute, and immediately after the rising tendency of the main blade load was confirmed again, the main blade rotation speed was changed to 400 rotations / minute. The granules were obtained by operating for 2 seconds. The bulk density of the granulated product thus obtained was about 1.6 times that of the raw material mixture (measured by powder tester).

The obtained granulated product was quantitatively supplied to the continuous two-roll type kneader shown in FIG. 2 by a table feeder and kneaded to obtain a high-concentration colorant-containing resin. The continuous two-roll type kneader used at this time had a roll outer diameter of 0.12 [m] and an effective roll length of 0.8 [m], and the operating conditions were high rotation side rolls (front rolls). )
The rotation speed was 50 rotations / minute, the roll rotation ratio was 1: 0.8, the roll gap was 0.0005 [m], and the heating and cooling medium temperatures in the roll were 60 ° C. on the raw material charging side of the high rotation roll and 45 on the kneaded material discharging side. C, and the low-roll roll material input side is 3
The temperature was 0 ° C. and the kneaded material discharge side was 30 ° C., the feed rate of the raw material mixture was 5 kg / hour, and the average residence time was about 9 minutes.

Next, the mixture of the high-concentration colorant-containing resin obtained as described above was cooled, and then roughly crushed by a hammer type crusher using a screen of 1 m / m, and then second kneading. The process was processed. That is, raw material 1 at the ratio of prescription
After weighing 0 kg and mixing with a high-speed stirring mixer under the conditions of a blade rotation speed of 850 rotations / minute and a processing time of 2 minutes,
Extruder (Ikegai Tekko PCM-3
Dilution and kneading were carried out at 0). Operating conditions are: barrel setting temperature 100 [° C], screw rotation speed 300 [revolution /
Min] and the raw material supply rate was 20 [kg / hr].

The obtained toner mixture was cooled with a cooling belt and then roughly crushed with a speed mill having a screen of φ2 [mm]. When this coarsely pulverized 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, no coarse pigment soul was observed. Next, this coarsely crushed product was crushed, classified, externally added and mixed with a carrier under the same conditions as in Example 1,
Used as a developer.

Example 3 Using the raw material having the same formulation as in Example 1, the same mixing and granulating apparatus as in Example 1 was used, and mixing and granulation were carried out under the same conditions as in Example 2. It was The obtained granulated product was used in Example 1
Kneading was performed using the same continuous two-roll type kneader as used in 1. to obtain a high-concentration colorant-containing resin. The operating conditions of the continuous two-roll type kneader at this time were as follows: the rotation speed of the high-rotation side roll (front roll) 100 rpm, the roll rotation ratio 1: 0.6, and the roll gap 0.0003 [m]. The temperature of the heating and cooling medium in the roll is 50 ° C. on the raw material charging side of the high rotation roll, 38 ° C. on the kneading material discharging side, 30 ° C. on the raw material charging side of the low rotation roll, and 2 on the kneading material discharging side.
It was 8 ° C. The feed rate of the raw material mixture is 4 kg.
/ H, the average residence time was about 7 minutes.

The obtained mixture of the high-concentration colorant-containing resin was crushed in the same manner as in Example 1, and then the binder resin and the charge control agent were added under the same formulation and treatment conditions as in Example 1. The resulting mixture was diluted and mixed and diluted to give a toner kneaded product, which was cooled and then roughly crushed with a speed mill. When this coarsely pulverized product was coated on an OHP sheet under the same conditions as in Example 1 and the coated product was observed with an optical microscope, coarse pigment lumps were hardly seen. Next, this coarsely crushed product was crushed, classified, externally added and mixed with a carrier under the same conditions as in Example 1 to obtain a developer.

Example 4 10 kg of the raw materials of the above formulation were mixed by using a high speed stirring type mixer as shown in FIG. The effective volume of the main body container 50 is 75 liters, and the stirring blade rotation speed is 700.
The mixture was mixed for 3 minutes at rotation / minute, and the resulting mixture was granulated using a roller compression granulator as shown in FIG. About 10 kg of the mixture obtained as described above was charged into the raw material hopper 31, and the arch breaker 32 was rotated at 30 revolutions / minute, while the screw rotation speed was 80 revolutions / minute with the biaxial screw feeder 33. , Supply amount 25kg /
The rate of H is supplied to the feed chamber 37, and the rotation speed is 1
While compressing between two rolls 34 of 5 revolutions / minute, the number of rotations of the tip rotor 36 of the disintegrator equipped with the screen 35 of φ4 m / m is 800 revolutions / minute,
The obtained pressed product was crushed to obtain a granulated product. The bulk density of the granulated product thus obtained was 1.2 times that of the mixture (measured by powder tester). The roll 34
Used a groove type.

The obtained granulated mixture was kneaded using the same continuous two-roll type kneader as in Example 1 to obtain a high-concentration colorant-containing resin. At this time, the continuous two-roll type kneader was operated under the following conditions: high rotation side roll (front roll) rotation speed 100 rotations / minute, roll rotation ratio 1: 0.6 roll gap 0.0003 [m], inside roll The temperature of the heating and cooling medium is 60 ° C. on the raw material feeding side of the high rotation roll, 45 ° C. on the kneading material discharging side of the high rotation roll, 38 ° C. on the raw material feeding side of the low rotation roll, and the kneading material discharging side of the low rotation roll. 32 ° C
Met. The feed rate of the raw material mixture is 14 kg /
H, average residence time was about 2 minutes. The obtained mixture of the high-concentration colorant-containing resin was diluted and mixed and kneaded in the same manner as in Example 1, cooled, and then crushed to obtain a coarsely pulverized product, which was then subjected to OHP treatment in the same manner as in Example 1. It was coated on the sheet. When this coating film was observed with an optical microscope, there were few coarse pigment clusters.

Comparative Example 1 10 kg of raw material weighed with the same formulation as in Example 1
Were mixed in a mixer having an internal volume of 75 liters as shown in FIG. 5 under the conditions of a blade rotation speed of 700 rotations / minute and a treatment time of 3 minutes, and 0.2 kg of the obtained mixture is shown in FIG. The mixture was charged into the raw material supply section of the three-roll mill, melt-kneaded in the gap between the three rolls, and the kneaded material was discharged from the kneaded material discharging section. In this kneaded product, the pigment was not sufficiently dispersed, so the same kneading operation was repeated 4 times in total to obtain a high-concentration colorant-containing resin. Repeat this operation multiple times to cool a total of 2 kg of kneaded material,
It was crushed to obtain a kneaded product. The three-roll mill used at this time had a roll outer diameter of 0.051 [m] and an effective roll length of 0.152 [m], and kneading was performed with a supply roll rotation speed of 70 [revolutions / minute] and a roll rotation ratio of , The ratio of the central roll to the supply roll 1 and the apron roll is 1: 1.5:
The roll gap was 2.5, the roll gap was 0.005 [m], and the roll temperature was 60 ° C.

The kneaded material crushed product obtained as described above is
Dilution mixing and kneading were carried out under the same conditions as in Example 1 in the proportions of the formulation, and after cooling, they were roughly crushed with a speed mill having a screen of φ1 [mm]. When this coarsely pulverized product was coated on an OHP sheet by the same method as in Example 1 and observed with an optical microscope, coarse pigment lumps were found here and there. Next, this coarsely pulverized product was pulverized by an I-type jet mill, and further fine powder and coarse powder were cut by an elbow jet classifier to obtain a cyan toner having an average particle diameter (D4) of 8.2 μm. The average particle size is the Coulter counter (T
A-II). Furthermore, colloidal silica 0.6
w. After externally adding t%, it was mixed with a resin-coated iron powder carrier to obtain a developer.

Comparative Example 2 Using the same formulation as in Example 1 and using 10 kg of raw material, in the same mixer as in Comparative Example 1, the number of blade rotation was 700 rpm.
Minutes, the treatment time was 5 minutes, and the resulting mixture was mixed.
2 kg was subjected to batch kneading operation a total of 6 times under the same conditions in the same three-roll mill as in Comparative Example 1 to obtain a high-concentration colorant-containing resin. This operation was performed plural times to obtain a kneaded product of 2 kg in total. This kneaded product was cooled and crushed, then diluted and mixed and kneaded under the same conditions as in Example 1 in the proportion of the formulation, and after cooling, crushed with a speed mill having a screen of φ1 [mm]. When this coarsely pulverized product was coated on an OHP sheet by the same method as in Example 1 and observed with an optical microscope, coarse pigment lumps were confirmed. This coarsely crushed material was crushed and classified in the same manner as in Example 1 to obtain an average particle diameter (D4).
Was 8.2 μm cyan toner. Furthermore, colloidal silica 0.6 w. After externally adding t%, it was mixed with a resin-coated iron powder carrier to obtain a developer.

[0048]

[Evaluation 1] An image development test was conducted using each of the developers obtained in Examples 1 to 4 and Comparative Examples 1 and 2, and the coloring power of each toner used in each developer and Confirmation of permeability was performed. In addition, the image output test was performed by Canon Inc. color laser copier 500 (CLC-50).
0). First, regarding the image density, OH
P sheet is used, and the amount of toner on the sheet is 0.5 mg
A solid image having a density of / cm ^{2 was formed} , fixing was performed at a temperature of 160 ° C., and a difference in image density was observed with a Macbeth reflection densitometer for evaluation. As a result, the average image density was 1.02 for the developer of Comparative Example 1, 1.06 for Comparative Example 2, and 1.19 for the developer of Example 1 and 1.2 for the developer of Example 2. 19, the developer of Example 3 was 1.22, and the developer of Example 4 was 1.10. In each case, the toner of Example has higher coloring power than the comparative example.

The image transparency was measured with an NDH-1001DP type HAZE meter manufactured by Nippon Denshoku Industries Co., Ltd. As a result, the average HAZE value of each developer is 21.0 in Comparative Example 1 and 20.8 in Comparative Example 2, while 18.0 in Example 1 and 18.0 in Example 2. No. 3 was 17.8 and Example 4 was 18.8, and the developers of the examples all had better transparency than the comparative examples. Next, images obtained by using the developers of Comparative Examples 1 and 2 and Examples 1 to 4 were projected on a white screen by an overhead projector and compared, and Examples 1 to 1 were obtained. The image of No. 4 was clear and bright cyan, but the images of Comparative Examples 1 and 2 were slightly dull and yellowish.

The Haze value is represented by the following equation. The better the dispersion of the colorant, the smaller the diffuse transmittance and therefore the smaller the Haze value.

[0051]

[Formula 1]

Next, using each of the toners of Examples 1 to 4 and Comparative Examples 1 and 2, a printing durability test of 10,000 sheets was carried out at 30 ° C., 80% high temperature and high humidity. However, with the toners of Examples 1 to 4, the toner was not scattered and an image without fog was obtained. On the other hand, in Comparative Example 1, toner scattering and fog occurred on 3,000 sheets, and in Comparative Example 2, toner scattering and fog occurred on 4,000 sheets.

Next, the method for producing the second color toner of the present invention will be described with reference to Examples and Comparative Examples. Example 5 The materials of the above formulation were dispersed as follows using the dispersing device shown in FIG. The tank used had a capacity of 50 liters, and the balls used as media were made of high alumina and had a diameter of 10 mm. The material of the tank was high alumina, and the material of the arm was zirconia. 5 kg of the above-prepared material was charged into the dispersion device, and dry dispersion was performed for 30 minutes with the rotation speed of the agitator arm being 100 rotations / minute.

The obtained mixture was quantitatively supplied to the continuous two-roll type kneader shown in FIG. 2 by a table feeder and kneaded to obtain a high-concentration colorant-containing resin. The continuous two-roll type kneader used at this time had a roll outer diameter of 0.12 [m] and an effective roll length of 0.8 [m], and the operating conditions were high rotation side rolls (front rolls). )
The rotation speed was 50 rotations / minute, the roll rotation ratio was 1: 0.8, the roll gap was 0.0005 [m], and the heating and cooling medium temperatures in the roll were 60 ° C. on the raw material charging side of the high rotation roll and 45 on the kneaded material discharging side. C, and the low-roll roll material input side is 3
The temperature was 0 ° C. and the kneaded material discharge side was 30 ° C., the feed rate of the raw material mixture was 5 kg / hour, and the average residence time was about 9 minutes.

Next, the mixture of the high-concentration colorant-containing resin obtained as described above was cooled, and then roughly crushed with a hammer type crusher using a screen of 1 m / m, and then second kneading. The process was processed. That is, raw material 1 at the ratio of prescription
After weighing 0 kg and mixing with a high-speed stirring mixer under the conditions of a blade rotation speed of 850 rotations / minute and a processing time of 2 minutes,
Extruder (Ikegai Tekko PCM-3
Dilution and kneading were carried out at 0). Operating conditions are: barrel setting temperature 100 [° C], screw rotation speed 300 [revolution /
Min] and the raw material supply rate was 20 [kg / hr].

The obtained toner mixture was cooled with a cooling belt and then roughly crushed with a speed mill having a screen of φ2 [mm]. This coarsely crushed product was dissolved in xylene to adjust the viscosity, and then a coating film was formed on the OHP sheet by an electric film applicator using a bar coater so that the film thickness was about 7 μm. When this coated material was observed with an optical microscope, no coarse pigment lumps were observed.
Next, this coarsely pulverized product was pulverized by an I-type jet mill, and further, coarse powder and fine powder were cut by an elbow jet classifier to obtain a cyan toner having an average particle diameter (D4) of 8.3 [μm]. . The average particle size is measured by Coulter Counter (TA
-II). Further, 0.6 wt% of colloidal silica was externally added to this, and then mixed with a resin-coated iron powder carrier to obtain a developer.

Example 6 Dispersion was carried out under the following conditions using the same disperser with the same formulation as in Example 5. Φ made of high alumina
Prescription material 5 using 10mm balls as media
Then, kg was charged into the dispersion device, and dry dispersion was carried out for 50 minutes at a rotation speed of the agitator arm of 100 rotations / minute.

The obtained mixture was quantitatively supplied to the continuous two-roll type kneader shown in FIG. 2 by a table feeder and kneaded to obtain a high-concentration colorant-containing resin. The continuous two-roll type kneader used at this time had a roll outer diameter of 0.12 [m] and an effective roll length of 0.8 [m], and the operating conditions were high rotation side rolls (front rolls). )
The rotation speed was 50 rotations / minute, the roll rotation ratio was 1: 0.8, the roll gap was 0.0005 [m], and the heating and cooling medium temperatures in the roll were 60 ° C. on the raw material charging side of the high rotation roll and 45 on the kneaded material discharging side. C, and the low-roll roll material input side is 3
The temperature was 0 ° C. and the kneaded material discharge side was 30 ° C., the feed rate of the raw material mixture was 5 kg / hour, and the average residence time was about 9 minutes.

Next, the mixture of the high-concentration colorant-containing resin obtained as described above was cooled and then roughly crushed with a hammer type crusher using a screen of 1 m / m, and then second kneading. The process was processed. That is, raw material 1 at the ratio of prescription
After weighing 0 kg and mixing with a high-speed stirring mixer under the conditions of a blade rotation speed of 850 rotations / minute and a processing time of 2 minutes,
Extruder (Ikegai Tekko PCM-3
Dilution and kneading were carried out at 0). Operating conditions are: barrel setting temperature 100 [° C], screw rotation speed 300 [revolution /
Min] and the raw material supply rate was 20 [kg / hr].

The obtained toner mixture was cooled with a cooling belt and then roughly crushed with a speed mill having a screen of φ2 [mm]. When this coarsely pulverized 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, no coarse pigment soul was observed. Next, this coarsely pulverized product was pulverized, classified, externally added and mixed with a carrier under the same conditions as in Example 5,
Used as a developer.

Example 7 Dispersion was performed under the same conditions as in Example 6 using the same disperser with the same formulation as in Example 5. The mixture thus obtained was kneaded using the same continuous two-roll type kneader as in Example 5 to obtain a high-concentration colorant-containing resin. At this time, the continuous two-roll type kneader was operated under the following conditions: high rotation side roll (front roll) rotation speed 100 rotations / minute, roll rotation ratio 1: 0.6, roll gap 0.00.
The temperature of the heating and cooling medium in the roll is 50 ° C. on the raw material feeding side of the high rotation roll, 38 ° C. on the kneaded product discharging side, and 30 ° C. on the raw material feeding side of the low rotation roll.
And the kneaded material discharge side was 28 ° C. The feed rate of the raw material mixture was 4 kg / H, and the average residence time was about 7 minutes.

The resulting mixture of the high-concentration colorant-containing resin was crushed in the same manner as in Example 5, and then the binder resin and the charge control agent were added under the same formulation and treatment conditions as in Example 5. The resulting mixture was diluted and mixed and diluted to give a toner kneaded product, which was cooled and then roughly crushed with a speed mill. When this coarsely pulverized product was coated on an OHP sheet under the same conditions as in Example 5 and the coated product was observed with an optical microscope, coarse pigment lumps were hardly seen. Next, this coarsely pulverized product was pulverized, classified, externally added and mixed with a carrier under the same conditions as in Example 5 to obtain a developer.

Example 8 Dispersion was carried out under the following conditions using the same disperser with the same formulation as in Example 5. Φ1 made of zirconia
Prescription material 5k using 0mm ball as media
g was put into the dispersion device, and dry dispersion was performed for 30 minutes at a rotation speed of the agitator arm of 100 rotations / minute.

The obtained mixture was kneaded using the same continuous two-roll type kneader as in Example 5 to obtain a high-concentration colorant-containing resin. At this time, the operating condition of the continuous two-roll type kneader is that the number of rotations of the high rotation side roll (front roll) is 10
0 revolutions / minute, roll rotation ratio 1: 0.6, roll gap 0.
0003 [m], the temperature of the heating and cooling medium in the roll is 60 ° C. on the raw material feeding side of the high rotation roll, 45 ° C. on the kneaded material discharge side of the high rotating roll, and 38 ° C. on the raw material feeding side of the low rotation roll. The kneaded product discharge side of the rotary roll was 32 ° C. The feed rate of the raw material mixture is 14 kg /
H, average residence time was about 2 minutes. The obtained mixture of the high-concentration colorant-containing resin was diluted, mixed and kneaded in the same manner as in Example 5, cooled, and then crushed. It was coated on the sheet. When this coating film was observed with an optical microscope, there were few coarse pigment clusters.

Comparative Example 3 10 kg of raw material weighed with the same formulation as in Example 5
Were mixed in a mixer having an internal volume of 75 liters as shown in FIG. 5 under the conditions of a blade rotation speed of 700 rotations / minute and a treatment time of 3 minutes, and 0.2 kg of the obtained mixture is shown in FIG. The mixture was charged into the raw material supply section of the three-roll mill, melt-kneaded in the gap between the three rolls, and the kneaded material was discharged from the kneaded material discharging section. In this kneaded product, the pigment was not sufficiently dispersed, so the same kneading operation was repeated 4 times in total to obtain a high-concentration colorant-containing resin. Repeat this operation multiple times to cool a total of 2 kg of kneaded material,
It was crushed to obtain a kneaded product. The three-roll mill used at this time had a roll outer diameter of 0.051 [m] and an effective roll length of 0.152 [m], and kneading was performed with a supply roll rotation speed of 70 [revolutions / minute] and a roll rotation ratio of , The ratio of the central roll to the supply roll 1 and the apron roll is 1: 1.5:
The roll gap was 2.5, the roll gap was 0.005 [m], and the roll temperature was 60 ° C.

The kneaded material crushed product obtained as described above is
Dilution mixing and kneading were carried out under the same conditions as in Example 1 in the proportions of the formulation, and after cooling, they were roughly crushed with a speed mill having a screen of φ1 [mm]. When this coarsely pulverized product was coated on an OHP sheet by the same method as in Example 1 and observed with an optical microscope, coarse pigment lumps were found here and there. Next, this coarsely pulverized product was pulverized by an I-type jet mill, and further fine powder and coarse powder were cut by an elbow jet classifier to obtain a cyan toner having an average particle diameter (D4) of 8.2 μm. The average particle size was measured with a Coulter counter (TA-II). Furthermore, colloidal silica 0.6 w. After externally adding t%, it was mixed with a resin-coated iron powder carrier to obtain a developer.

Comparative Example 4 10 kg of raw material was used in the same formulation as in Example 5, and the same mixer as in Comparative Example 1 was used.
Minutes, the treatment time was 5 minutes, and the resulting mixture was mixed.
2 kg was subjected to batch kneading operation a total of 6 times under the same conditions in the same three-roll mill as in Comparative Example 1 to obtain a high-concentration colorant-containing resin. This operation was performed plural times to obtain a kneaded product of 2 kg in total. This kneaded product was cooled and crushed, then diluted and mixed and kneaded under the same conditions as in Example 1 in the proportion of the formulation, and after cooling, crushed with a speed mill having a screen of φ1 [mm]. When this coarsely pulverized product was coated on an OHP sheet by the same method as in Example 1 and observed with an optical microscope, coarse pigment lumps were confirmed. This coarsely pulverized product was pulverized and classified in the same manner as in Example 1 to have an average particle diameter (D4).
Was 8.2 μm cyan toner. Furthermore, colloidal silica 0.6 w. After externally adding t%, it was mixed with a resin-coated iron powder carrier to obtain a developer.

[0068]

[Evaluation 2] An image development test was conducted using each of the developers obtained in Examples 5 to 8 and Comparative Examples 3 and 4, and the coloring power of each toner used in each developer and Confirmation of permeability was performed. In addition, the image output test was performed by Canon Inc. color laser copier 500 (CLC-50).
0). First, regarding the image density, OH
P sheet is used, and the amount of toner on the sheet is 0.5 mg
A solid image having a density of / cm ^{2 was formed} , fixing was performed at a temperature of 160 ° C., and a difference in image density was observed with a Macbeth reflection densitometer for evaluation. As a result, the average image density was 1.02 for the developer of Comparative Example 3, 1.06 for Comparative Example 4, and 1.21 for the developer of Example 5 and 1.1 for the developer of Example 6. 23, the developer of Example 7 was 1.25, and the developer of Example 8 was 1.15. In all cases, the toner of Example has a higher coloring power than the comparative example.

Further, the image transparency was measured with an NDH-1001DP type HAZE meter manufactured by Nippon Denshoku Industries Co., Ltd. The Haze value has the same meaning as described in the first method of the present invention. As a result, the average HAZE value of each developer was 21.0 in Comparative Example 3 and 4 in Comparative Example.
Is 20.8, whereas in Example 5 17.9, Example 6
17.7, Example 7 is 17.4, Example 8 is 1
It was 8.4, and the developers of the examples all had excellent transparency as compared with the comparative examples. Next, images obtained by using the developers of Comparative Examples 3 and 4 and Examples 5 to 8 were projected on a white screen by an overhead projector and compared, and Examples 5 to 5 were obtained. The image of No. 8 was clear and bright cyan, but the images of Comparative Examples 3 and 4 were slightly dull and yellowish.

[0070]

As described above, in the toner manufactured by the first color toner manufacturing method of the present invention, the bulk density is increased by granulating the raw material mixture in the first kneading step, It was possible to improve the fluidity (flushing property) and further improve the wettability. or,
By kneading the granulated product of the mixture using a continuous two-roll type kneader, kneading has conventionally required repeated batch operation by human judgment requiring advanced skill cultivated from long experience. According to the method of the present invention, the operation of the present invention does not require a high level of empirical skill, and continuous processing and unmanned operation are possible, and the quality is stable, highly economical, and highly colored.
It is possible to manufacture a color toner having excellent transparency.

Further, as described above, in the second color toner manufacturing method of the present invention, by using a dispersing machine using a medium in the step of mixing the raw materials in the first kneading step, It becomes possible to make highly dispersed and unprecedented mixing, and by using a continuous two-roll type kneader for the kneading in the first kneading step, conventionally, it requires a high degree of skill cultivated from long experience. Moreover, the kneading operation, which requires repeated batch operation by a human means, does not require empirical high skill, is continuous processing, enables unmanned operation, and has stable quality. It is possible to produce a highly colored and highly colored color toner having a high susceptibility.

[Brief description of drawings]

FIG. 1 is an example of a mixing / granulating apparatus used in a mixing / granulating step in a first kneading step of a first color toner manufacturing method of the present invention.

FIG. 2 shows an example of a continuous two-roll type kneader used in the kneading step of the first kneading step of the present invention.

FIG. 3 is a diagram showing a manufacturing process of a first color toner manufacturing method of the present invention and a manufacturing process of a conventional color toner.

FIG. 4 shows an example of a three-roll mill used in a comparative example.

5 is an example of a mixer used in Example 4. FIG.

6 is an example of a granulator used in Example 4. FIG.

FIG. 7 is an example of a conventional mixer.

FIG. 8 is an example of a dispersion device used in the step of mixing raw materials in the first kneading step of the second color toner manufacturing method of the present invention.

FIG. 9 is a process drawing of a second color toner manufacturing method of the present invention and a conventional color toner manufacturing process drawing.

FIG. 10 is an example of another dispersing device used in the step of mixing the raw materials in the first kneading step of the second color toner manufacturing method of the present invention.

FIG. 11 is an example of another dispersing device used in the step of mixing the raw materials in the first kneading step of the second color toner manufacturing method of the present invention.

FIG. 12 is an example of another dispersing device used in the step of mixing the raw materials in the first kneading step of the second color toner manufacturing method of the present invention.

[Explanation of sign]

 1: Main body casing 2: Jacket 3: Main body cover 4: Main blade 5: Granulation blade 11: Raw material supply section 12: Kneaded material discharge section 13: Front roll 14: Back roll 15, 16: Heating and cooling medium supply / discharge section 17, 18: Roll driving motor 21: Supply roll 22: Central roll 23: Apron roll 24: Raw material supply part 25: Kneaded material discharge part 26: Discharge scraper 27: Heating / cooling medium supply / discharge part 28, 29: Roll gap Adjustment handle 30: Roll driving motor 31: Raw material hopper 32: Arch breaker 33: Screw feeder 34: Roll 35: Screen 36: Rotor 37: Feed chamber 50: Main container 51: Stirring blade 52: Discharge port 53: Motor 54: Main body container 55: Stirring screw 56: Discharge port 71 : Main body container 72: Agitator shaft 73: Agitator arm 74: Media (ball) 75: Drum 76: Ball 77: Main body container 78: Ball 79: Rubber elastic body 80: Shaft 81: Eccentric vibration source 82: Main body casing 83: Cyclone 84: Screw 85: Motor 86: Supply rotor 87: Blower 88: Bag filter 89: Blower

Claims (5)

[Claims] 1. A first kneading step in which a raw material mixture containing at least a binder resin and a colorant is melt-kneaded in a kneader and a kneaded material obtained in the first kneading step is at least the same kind or different kind. And a second kneading step in which the diluted mixture is melt-kneaded, and the kneaded product obtained in the second kneading step is crushed to produce a color toner. In the method, the raw material mixture is granulated in the first kneading step, the obtained granulated product is melt-kneaded using a continuous two-roll type kneader, and the average residence time of the kneaded product in the kneader is A method for producing a color toner, which is at least 2 minutes or more. 2. The method for producing a color toner according to claim 1, wherein the bulk density of the granulated product obtained in the first kneading step is 1.1 times or more that of the raw material mixture. 3. A first kneading step of melting and kneading a raw material mixture containing at least a binder resin and a colorant with a kneader,
The kneading machine obtained in the first kneading step has a second kneading step of diluting and mixing at least the same or different binder resins, and further melt kneading the diluted mixture, and the second kneading step In a method for producing a color toner by pulverizing the kneaded product to produce a color toner, a dry type disperser using a medium is used for mixing the raw materials in the first kneading step, and a continuous two-roll type is used for kneading the raw material mixture. A kneader is used, and the average residence time of the kneaded product in the kneader is at least 2
The method for producing a color toner is characterized by being at least a minute. 4. The method for producing a color toner according to claim 1, wherein the rotation speed of the rotating roll of the kneading machine used in the first kneading step is 150 rotations / minute or less. 5. The method for producing a color toner according to claim 1, wherein the rotation ratio of each rotating roll of the kneading machine used in the first kneading step is in the range of 1: 1 to 1: 0.1.