JP2002156791A - Device and method for producing masterbatch for toner production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device and a method for producing master batch for toner production which enables production of a masterbatch, in such a manner that pigment is supplied into binder resin, in a state with the pigment being dispersed quantitatively and uniformly therein, and the same time, enables prevention of the degradation of performance of the toner which is obtained by using the masterbatch. SOLUTION: This production device 10 is provided with a screw feeder 12 which supplies the binder resin and a vibrating feeder 11 which supplies the pigment on the downstream side of the screw feeder 12. This producing device 10 is also provided with an open roll mixer 13 as a melt mixing device, which supplies the binder resin supplied from the screw feeder 12, in between a pair of open rolls 13a and winds the binder resin, which is fused by the rotation of the open rolls 13a onto the surface of the open rolls 13a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a masterbatch for producing a toner used in, for example, an electrophotographic method, an electrostatic printing method, and the like. The present invention relates to a masterbatch manufacturing apparatus and a manufacturing method for manufacturing a toner that can be manufactured by being uniformly dispersed in a binder resin.

[0002]

2. Description of the Related Art Generally, in electrophotography, a photoconductive substance is used to form an electric latent image on a photoreceptor by various methods, and then the latent image is developed using toner. Further, a method of transferring a toner image to a transfer material such as paper and then fixing the toner image by various methods to obtain an object is adopted.

[0003] The toner (dry toner) is prepared by using a master batch composed of a binder resin and a pigment as a main raw material, and further adding raw materials such as a charge control agent, a wax, and other additives. Describing the method of manufacturing the toner, the manufacturing process of the toner is mainly a manufacturing process of a masterbatch composed of a binder resin and a pigment, a diluting and kneading process of the masterbatch and other raw materials, a crushing process of the kneaded material,
It consists of a classification step and an external addition step.

[0004] The master batch manufacturing apparatus also includes a table feeder for supplying binder resin and a pigment, and an open roll kneader. The table feeder includes a table, and the table is provided with a supply port that opens downward. A scraper that rotates at a low speed is provided on the upper surface of the table. The scraper scrapes the raw material on the table and moves the raw material toward the supply port, so that the raw material can be supplied from the supply port to a lower position.

Next, the open roll kneader will be described. The open roll kneader has a pair of open rolls, each of which has a cylindrical shape having a spiral groove on its surface, and extends in parallel with each other while facing each other. Both ends are rotatably supported by a bearing in a state where a gap is provided between the two open rolls at a constant interval. The two table feeders are installed on the open roll, a table feeder for binder resin supply is installed on one end of the open roll, and a table for pigment supply is provided on the downstream side, that is, the other end of the open roll. A feeder is installed.

In order to manufacture a master batch using the above-mentioned manufacturing apparatus, first, binder resins and pigments are respectively weighed in predetermined amounts, and then each raw material is supplied into a table feeder. The resin is supplied from the supply port of the table feeder to between the open rolls. Then, the binder resin is melted by the rotation and heating of both open rolls, and becomes a highly viscous fluid. Next, when the pigment is supplied from the supply port of the table feeder to between the open rolls, the pigment is kneaded into the molten binder resin to produce a master batch (master batch production process). Next, the dilution kneading step, the kneaded material pulverizing step, the classifying step, the external adding step, and the like are performed to produce a toner.

[0007]

However, in the above-mentioned conventional masterbatch manufacturing process, the pigment has physical properties that are lower in fluidity than the binder resin, and therefore, the pigments are gathered in a part on the table. Existing. Then
When supplying the pigment to the open roll kneading machine using the table feeder, the pigment in the state of being gathered on the table is scraped off by the scraper,
Moreover, it is intermittently supplied between the open rolls.
As a result, the pigment is kneaded into the binder resin in a united state, and the quantitativeness of the pigment in the obtained master batch is deteriorated. There is a problem that the performance of the toner using the batch is deteriorated.

[0008] The present invention has been made by focusing on the problems existing in such prior art. The purpose is to produce a masterbatch supplied in a binder resin in a state where the pigment is quantitatively and uniformly dispersed, and to decrease the performance of the toner obtained using the masterbatch. It is an object of the present invention to provide an apparatus and a method for producing a master batch for producing a toner, which can prevent the occurrence of toner.

[0009]

According to a first aspect of the present invention, there is provided a masterbatch manufacturing apparatus for manufacturing a toner, comprising: a binder resin supply mechanism for supplying a binder resin; A melt-kneading device that supplies the binder resin supplied from the binder resin supply mechanism between the open rolls and winds the binder resin melted by the rotation of the open roll around the roll surface, and downstream from the binder resin supply mechanism. A pigment supply mechanism for supplying a pigment at a position with a fixed-quantity feeder, and supplying the binder resin supplied from the binder resin supply mechanism between the open rolls to roll the binder resin melted by rotation of the open roll. The masterbatch is manufactured by wrapping around the surface and melting and kneading the pigment supplied from the pigment supply mechanism with the binder resin wrapped around the roll surface. It is intended to.

According to a second aspect of the present invention, there is provided an apparatus for producing a masterbatch for producing a toner according to the first aspect, wherein the fixed-quantity feeder is a vibration feeder.

According to a third aspect of the present invention, there is provided a method for producing a masterbatch for producing a toner, wherein the apparatus for producing a masterbatch for producing a toner according to the first or second aspect is used. The binder resin is supplied between the open rolls from the resin supply mechanism, the binder resin is melted by the rotation of the open roll and wound around the roll surface, and the pigment is supplied from the pigment supply mechanism between the open rolls to the roll surface. The masterbatch is manufactured by melt-kneading the wound binder resin.

[0012]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIGS. 1 and 2 are schematic diagrams showing a master batch manufacturing apparatus 10 (hereinafter, simply referred to as a manufacturing apparatus 10) for manufacturing a toner. As shown in FIGS. 1 and 2,
The manufacturing apparatus 10 includes a screw feeder 12 as a binder resin supply mechanism for supplying a binder resin, and a vibration feeder 11 as a quantitative feeder of the pigment supply mechanism for supplying pigment at a position downstream of the screw feeder 12. . Further, an open roll kneader as a melt kneading device for supplying the binder resin supplied from the screw feeder 12 between the pair of open rolls 13a and winding the binder resin melted by the rotation of the open roll 13a around the surface of the open roll 13a. 13 is provided.

The binder resin supplied from the screw feeder 12 is supplied between the pair of open rolls 13a, and the molten binder resin is wound around the surface of the open roll 13a by the rotation of the open roll 13a, and supplied from the vibration feeder 11. Open roll 13a
It is configured so that a masterbatch is manufactured by melt-kneading the binder resin wound around the surface.

First, the screw feeder 12 will be described. The screw feeder 12 is located behind one end (left side in FIG. 1) of a pair of open rolls 13a (FIG. 1).
In the upper part, a hopper 15 which is mounted on a mounting table 14 installed at an upper position and which can store the binder resin is provided.
A lower part of the hopper 15 communicates with the inside of the hopper 15 and is provided with a transport path 16 which extends from the hopper 15 toward the open roll kneader 13 in a cylindrical shape. It is arranged above the gap between the open rolls 13a.

A screw (not shown) spirally extending from the hopper 15 to the tip of the transport path 16 in the transport path 16.
Are rotatably provided. Then, the binder resin is transported from the hopper 15 side to the distal end side of the transport path 16 by the rotation of the screw in a predetermined direction, and the open roll kneader 1 is rotated.
3 is supplied between a pair of open rolls 13a.

Next, the vibration feeder 11 will be described. The vibration feeder 11 is mounted on a mounting table 14 installed on the downstream side (the right side in FIG. 1) of the screw feeder 12, and can accommodate the pigment. The hopper 15 is provided on the upper part. As shown in FIG. 2, a vibration table 11 a, which is capable of accommodating a pigment and is capable of vibrating, is provided below the hopper 15 on the downstream side of the conveyance path 16 of the screw feeder 12. The tip of the vibration table 11a is a pair of open rolls 13a.
It is arranged above the gap between them. Then, by vibrating the vibration table 11a, the vibration table 11a
An appropriate amount of the pigment contained therein is supplied quantitatively and continuously between the open rolls 13a of the open roll kneader 13.

Next, the open roll kneader 13 will be described. A pair of open rolls 13a each have a cylindrical groove (not shown) on its surface as shown by a broken line in FIGS. The two open rolls 13a have opposite ends and extend in parallel, and both ends are supported by bearings with a gap provided between the open rolls 13a at a fixed interval. Then, as shown by arrows in FIG. 2, the motors are configured to be rotatable inward by a motor (not shown).

Each of the open rolls 13a has a hollow interior and is formed so as to be capable of supplying a heat medium such as steam or hot water or a coolant such as cooling water. It is configured to be able to adjust.

Then, the pigment is released from the binder resin and the vibrating table 11a having moved in the transport path 16 into the open rolls 13.
a, and the pigment and the binder resin are melt-kneaded between the pair of open rolls 13a to produce a master batch. As shown by a broken line in FIG. 2, a collecting unit 17 is provided at a position below the other end of the open roll 13a to collect a master batch produced by melting and kneading by rotation of the pair of open rolls 13a. .

Next, the raw material of the toner will be described. First, the kind of the binder resin is not particularly limited, and a known binder resin for a black toner or a color toner can be used. Examples include polyester resins, styrene-based polymers such as polystyrene and styrene-acrylate copolymers, acrylic polymers such as polymethyl methacrylate, polyolefin-based polymers such as polyethylene, polyurethane resins, and epoxy resins. These binder resins are used alone or in combination of two or more. The binder resin is usually blended in the toner in an amount of 80 to 95% by weight.

The pigment is not particularly limited. Red pigments such as quinacridone, brilliant carmine 6B and permanent red; yellow pigments such as benzimidazolone and dichlorobenzidine; blue pigments such as cobalt blue and copper phthalocyanine; And green pigments such as chromium oxide and Pigment Green B, and black pigments such as carbon black and acetylene black.
These pigments are used alone or in combination of two or more.
The pigment is usually blended in the toner in an amount of 3 to 10% by weight.

The raw materials of the toner other than the binder resin and the pigment include additives such as a charge control agent and a wax. The charge control agent is not particularly limited, and a known charge control agent for negatively charged or positively charged toner for black toner or color toner can be used. Examples of the charge control agent for negatively charged toner include surfactants such as chromium, zinc, zirconium complex or salt compound of salicylic acid or a derivative thereof, azo complex dyes, and long-chain alkyl carboxylate. Examples of the charge control agent for a positively charged toner include a nigrosine dye or a derivative thereof, a quaternary ammonium salt, and a guanidine salt. Examples of the wax include natural waxes such as carnauba wax and synthetic waxes, silicone polymers, higher fatty acids, polyolefin polymers, and low molecular weight polymers.

Next, a method for producing a master batch and a toner using the production apparatus 10 will be described.

Now, a predetermined amount of the binder resin and the pigment are measured,
These raw materials are supplied into each hopper 15. Thereafter, the manufacturing apparatus 10 is operated to rotate the screw in the transport path 16 in a predetermined direction, and the hopper 1 of the screw feeder 12 is rotated.
The binder resin is transported in the transport path 16 from the fifth side to the open roll kneader 13 side.

Next, a heating medium is supplied into one open roll 13a (left side in FIG. 2) to heat it, and a refrigerant is supplied into the other open roll 13a (right side in FIG. 2) to open one open roll 13a (right side in FIG. 2). The temperature is set lower than the roll 13a to generate a temperature difference between the two open rolls 13a. At the same time, one of the open rolls 13a is rotated such that its rotational speed is higher than the rotational speed of the other open roll 13a.

Then, the binder resin transported in the transport path 16 falls between one ends of the pair of open rolls 13a and is supplied. The binder resin supplied between the two open rolls 13a is heated by the heat transfer action on the surface of one open roll 13a, and at the same time, rapidly rotates in the gap between the open rolls 13a as the two open rolls 13a rotate. Compressive force and shearing force are applied to melt while generating heat and wind around the surface of the open roll 13a.

Subsequently, the hopper 15 of the vibration feeder 11
The pigment inside is accommodated in the vibration table 11a, and the pigment is dropped on the binder resin wound around the surface of the open roll 13a and supplied by the vibration of the vibration table 11a. At this time, the pigment is loosened without being gathered in the vibration table 11a due to the vibration of the vibration table 11a, and is uniformly dispersed. Therefore, the pigment is quantitatively supplied in a state of being uniformly dispersed in the binder resin.

The binder resin is an open roll 13a.
In a state where the pigment adheres to the surface and the pigment is kneaded on the surface of the binder resin, the two raw materials are repeatedly kneaded under the compressive shearing force, and the other materials of the open roll 13a are rotated by the difference in rotation speed of the pair of open rolls 13a. It is transferred to the end side. At this time, since the binder resin is in a molten state, the pigment adheres to the binder resin, and the problem of dropping from between the open rolls 13a is eliminated. Furthermore, since both are kneaded with the pigment attached to the molten binder resin, separation of the binder resin and the pigment in the obtained toner is prevented. As a result, a masterbatch in which the pigment is uniformly dispersed in the binder resin is manufactured, and the masterbatch is collected by the collection unit 17 from between the pair of open rolls 13a on the other end side.

Next, a charge control agent is added to the master batch,
Waxes, additives, and the like are appropriately added, and the mixture is uniformly dispersed in the binder resin by heating or the like, and then cooled and solidified to prepare a kneaded product. Subsequently, the mixture is roughly pulverized, finely pulverized and classified, and then subjected to a surface treatment to produce a toner. Therefore, since there is almost no change in the mixing ratio of the raw materials during the production of the master batch, there is almost no change in the mixing ratio of the raw materials of the obtained toner.

The effects exerted by the above embodiment will be described below.

Using a vibration feeder 11, a pigment having a lower fluidity than a binder resin is applied to a vibration table 11a.
The manufacturing apparatus 10 was configured to supply the mixture to the open roll kneader 13 while vibrating the inside. Therefore, in a state where the pigment is uniformly dispersed, the open roll kneader 13
Can be supplied to Therefore, unlike the conventional case in which the pigment is supplied to the open roll kneader 13 using the table feeder, the pigment in a bundled state is
Intermittent supply can be prevented. As a result, the pigment can be supplied quantitatively in the obtained master batch, and the pigment can be uniformly dispersed in the binder resin, thereby preventing the performance of the toner using the master batch from deteriorating. be able to.

Since the pigment is uniformly dispersed in the binder resin, when the resulting toner is used to develop a latent image using, for example, electrophotography, the image quality of the toner image becomes uneven, dull, and transparent. As a result, the image quality can be prevented from deteriorating.

A vibrating feeder 11 was provided downstream of the screw feeder 12, and after the binder resin was melted, a pigment was supplied to cause the pigment to adhere to the binder resin. for that reason,
The binder resin and the pigment are simultaneously supplied between the open rolls 13a, so that the problem that the pigment does not adhere to the unmelted binder resin and the pigment falls from between the open rolls 13a can be eliminated. Accordingly, it is possible to suppress a decrease in pigment, to produce a masterbatch having a proper blending ratio of the binder resin and the pigment, and to prevent a decrease in performance of a toner obtained by using the masterbatch. can do.

Further, since both are kneaded with the pigment attached to the molten binder resin, separation of the binder resin and the pigment in the obtained toner can be prevented.

Since the pigment is uniformly dispersed in the binder resin, unlike the case where the charge control agent, additives and the like and the pigment are uniformly dispersed in the binder resin in the dilution and kneading process, The time can be shortened.

[0037]

[Examples] Hereinafter, the above embodiment will be described more specifically with reference to examples.

Styrene-butyl acrylate copolymer as binder resin: glass transition temperature (Tg): 56 ° C., flow softening point (Tf): 115 ° C., weight average molecular weight 5 × 1
0 ^4, using the number average molecular weight 4 × 10 ^3}, Permanent Red F2R as a pigment, C. I. 12310 was used.

The open roll kneader 13 had a pair of open rolls 13a, each of which had a diameter of 138 mm and a length of 785 mm, and a gap between the pair of open rolls 13a of 0.3 mm. The conveying path 16 of the screw feeder 12 had a diameter of 50 mm and a length of 600 mm.

First, 70 parts by weight of the binder resin were supplied to the hopper 15 of the screw feeder 12 and 30 parts by weight of the pigment were supplied to the hopper 15 of the vibration feeder 11. Next, the binder resin was supplied from the screw feeder 12 to the open roll kneader 13 under the conditions of 2 to 10 kg / h. Then, the front open roll 13a is adjusted to a temperature of 80 ° C., the rear open roll 13a is adjusted to a temperature of 30 ° C., and the front open roll 13a is rotated at a rotation speed of 70 rpm and the rear open roll 13a is rotated at a rotation speed of 60 rpm. Was melted and wound around the surface of the open roll 13a.

Next, the vibration feeders 11 to 2 to 10
The pigment was supplied to the open roll kneader 13 under the condition of kg / h, and the pigment was kneaded into the molten binder resin to produce a master batch. As a result, a master batch in which the pigment was uniformly dispersed in the binder resin could be obtained.

Subsequently, 40 parts by weight of the master batch, 100 parts by weight of the binder resin, and 1 part by weight of a negatively chargeable charge control agent {Oxo-Gluco compond (Copy Charge NCA cp2243, manufactured by Clariant Co., Ltd.)} As a result of diluting and kneading 3 parts by weight of polywax as a product (melting point 128 ° C.) Hoechst Wax PE130, manufactured by Hoechst, a toner could be produced.

The present embodiment can be embodied with the following modifications.

In the embodiment, the screw feeder 12 is used as the binder resin supply mechanism, but the table feeder, the vibration feeder 11, and the like are used as the binder resin supply mechanism.
A mono pump or the like may be used. Further, the vibration feeder 11 is used as the pigment supply mechanism, but a screw feeder 12 which is a quantitative feeder may be used.
When the screw feeder 12 is used as the fixed amount feeder, since the screw rotates in the transport path 16 of the screw feeder 12 to constantly stir the pigment, it is possible to prevent the pigment from staying in the transport path 16. Therefore, it is possible to improve the quantitativeness of the master batch by eliminating the problem that the mass of the pigment drops from the transport path 16 to the open roll kneader 13.

In the embodiment, a pair of open rolls 1
Although the open roll kneader 13 using the 3a is used, an open roll kneader 13 using three or more open rolls 13a may be used.

In the embodiment, the open roll kneader 1
3. Screw feeder 12 and vibratory feeder 11
The vibration feeder 11 for supplying a charge control agent and the vibration feeder 11 for supplying an additive (such as wax) are provided downstream of the vibration feeder 11. After the master batch is manufactured, the charge control agent and the additive are added to the master batch. The toner may be manufactured by continuously supplying an agent or the like.

Further, the technical ideas that can be grasped from the above embodiment will be described below.

The apparatus according to claim 1, wherein the fixed-quantity feeder is a screw feeder. In the case of such a configuration, since the screw rotates and constantly agitates the pigment in the transport path of the screw feeder, the pigment can be prevented from staying in the transport path. Therefore, it is possible to improve the quantitativeness of the master batch by eliminating the problem that the mass of the pigment is supplied between the open rolls from the transport path.

[0049]

As described above in detail, according to the present invention, the following effects can be obtained.

According to the master batch production apparatus for producing a toner according to the first aspect of the present invention, a master batch supplied to a binder resin in a state where a pigment is quantitatively and uniformly dispersed is produced. And the performance of the toner obtained by using the master batch can be prevented from deteriorating.

According to the master batch production apparatus for producing a toner according to the second aspect of the present invention, in addition to the effects of the first aspect, the pigment is quantitatively and uniformly dispersed in the binder resin. Can be supplied.

According to the method for producing a masterbatch for producing a toner according to the third aspect of the present invention, a masterbatch supplied into a binder resin in a state where a pigment is quantitatively and uniformly dispersed is produced. Can be.

[Brief description of the drawings]

FIG. 1 is a schematic front view showing a manufacturing apparatus according to an embodiment.

FIG. 2 is a schematic side view showing the manufacturing apparatus of the embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Master batch manufacturing apparatus for toner production 11 ... Vibration feeder as pigment supply mechanism 12 ... Screw feeder as binder resin supply mechanism 13 ... Open roll kneader as melt kneading apparatus 13a ... Open roll

Claims (3)

[Claims] 1. A binder resin supply mechanism for supplying a binder resin, a binder resin supplied from the binder resin supply mechanism being supplied between open rolls, and a binder resin melted by rotation of the open rolls. A melt-kneading device that winds around the roll surface; and a pigment supply mechanism that supplies a pigment by a fixed-quantity feeder at a position downstream of the binder resin supply mechanism. The binder resin supplied from the binder resin supply mechanism is opened by an open roll. In the meantime, the binder resin melted by the rotation of the open roll is wound around the roll surface, and the pigment supplied from the pigment supply mechanism is melt-kneaded with the binder resin wound around the roll surface to produce a master batch. A masterbatch manufacturing apparatus for manufacturing a toner, characterized in that: 2. The apparatus according to claim 1, wherein the fixed-quantity feeder is a vibration feeder. 3. An open roll, wherein the binder resin is supplied between the open rolls from the binder resin supply mechanism using the master batch manufacturing apparatus for toner production according to claim 1 or 2. The binder resin is melted and wound around the roll surface by the rotation of the toner, and a pigment is supplied between the open rolls from a pigment supply mechanism to melt-knead the binder resin wound around the roll surface to produce a master batch. Method of manufacturing a masterbatch.