JP2008026457A - Toner classifier - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus and method for producing a toner capable of assuring stable classification granularity, and producing a toner at high throughput and high yield without toner sticking within the apparatus for producing the toner including a mechanical centrifugal air classifier (TSP; toner separator and TTSP; tandem toner separator) for a long period of time by solving the problems in the air classifier. <P>SOLUTION: The toner classifier has a relation of classifier outlet internal pressure<outlet piping internal pressure in the minus static pressure in the outlet piping and classifier outlet of the classifier of an impeller type (common name: TSP, TTSP (toner separator, tandem toner separator)). <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a toner manufacturing apparatus and a manufacturing method used in an image forming method such as an electrophotographic method, an electrostatic recording method, an electrostatic printing method, or a toner jet recording method.

In an image forming method such as electrophotography, a toner for developing an electrostatic image is used. The toner production method is roughly classified into a pulverization method and a polymerization method, and a simple and popular production method includes a pulverization method. As a general production method by this pulverization method, a binder resin for fixing to a transfer material and a colorant for producing a color as a toner are used, and if necessary, a charge is imparted to the toner particles. Add the charge control agent, magnetic material for imparting transportability to the toner itself, additives such as mold release agent, fluidity imparting agent, etc., mix, melt knead, cool and solidify, then crush the kneaded product The toner is finely divided by a means and classified into a desired particle size distribution by a classification means, or a fluidizing agent is further added to obtain a toner for image formation. In the case of a toner used in the two-component development method, various magnetic carriers and the above toner are mixed and then used for image formation.
In recent years, as a toner material for high-speed printing, a toner having a low melting point resin and a small particle size release agent, typically Wax, has been increasing in order to obtain high resolution. In some cases, sticking occurs due to the low molecular weight and low melting point properties of Wax that appears or desorbs from the toner particle interface and is released, and adhesion to the production machine has become a problem.

  FIG. 1 is a block diagram illustrating an example of a fine powder manufacturing system (toner manufacturing system). This system includes a pulverizing means for pulverizing the raw material and a classifying means for classifying the pulverized raw material with a particle size.

  In the system of FIG. 1, the classifying means (832) uses the raw material pulverized by the pulverizing means (831), coarse powder having a particle size larger than the specified particle size, medium powder (product) within the specified particle size, and the specified particle size. The particle size is classified into fine powders of small particle size. The coarse powder is pulverized again by the pulverizing means (831) and supplied again to the classifying means (832). The fine powder is collected and returned to the raw material mixing step. As the pulverizing means, a known air-flow pulverizer or mechanical pulverizer is used. As the classifying means, a multi-divided airflow classifier and a vertical axis airflow classifier, which will be described later, are used.

  The toner classification device can be classified into a non-impeller type classification device and an impeller type classification device. However, the present invention can be effectively applied to the latter impeller type toner classification device. The impeller-type toner classifier includes, for example, a mechanical centrifugal force type wind classifier (commonly known as TSP (Japanese Patent Laid-Open No. 10-118571 or Japanese Patent Laid-Open No. 2001-104888). Toner separator)), and a wind classifier called TTSP (tandem toner separator) disclosed in Japanese Patent Application Laid-Open No. 2001-293438 of Patent Document 3 or Japanese Patent Application No. 2005-216675 of Patent Document 4 and drawings Is included. The former TSP classifier performs classification by balancing the centrifugal force (coarse powder collection / removal) by the blades provided on the rotating rotor and the centripetal force by the fan suction force (thus collecting / removing fine powder from the periphery of the rotating shaft). The latter TTSP classifier has two impeller-type classifying rotors that are supported on one side in a casing and can be driven by a motor, and the classifying rotors on the same axis are arranged in the axial direction. Between the end portions of the classifying rotors facing each other, having a cover disk closed at the first end of the classifier, and a mechanism for taking out fine particles or medium particles at the second end in the axial direction. The first end portions of both of the classification rotors are arranged so that the end faces face each other, forming a minute flow space in the axial direction and forming a minute flow space in the axial direction A.

  By the way, in recent years, due to a demand for high image quality, there is a demand for a toner having a sharp particle size distribution with excellent dot reproducibility because there is little dot fluctuation in the development and transfer processes. For this reason, there is a demand for an apparatus capable of accurately classifying toner of 4 μm or less and obtaining toner having a component of 5 μm or more in a high yield as a manufacturing apparatus.

  In recent years, toners that are easily adhered and fused have been used particularly in response to the following requirements. That is, (1) From the viewpoint of reducing energy consumption, the toner is fixed at a low temperature. (2) In a color toner, a binder resin having a low softening point is used because of the demand for color mixing. (3) There is a need for a toner containing a release agent that supports oilless fixing.

  These toners tend to adhere and fuse inside the pulverizer, classifier, and mixer. In particular, the release agent-containing toner has a significant problem with toner adhesion and toner fusion, and in a pulverizer and a classifier, the progress of toner adhesion and the progress of toner fixation reduce the toner productivity. The detachment of the toner agglomerates causes pulsation of the dust concentration while the classifier is in operation, thereby lowering the classification accuracy. Further, in the mixer, mixing of the fixed toner deteriorates the quality of the product and leads to a decrease in image quality.

  The above inconvenience is remarkable in the above-described TTSP. TTSP or TSP is excellent in classification accuracy, but the product outlet classified by the rotor and the stator is narrow, and therefore, there is a problem in the discharge property due to toner adhesion and toner fusion.

The main causes of deterioration in product discharge due to toner adhesion and toner fixation during continuous operation in TTSP or TSP are as follows.
1. ) In the case of the classification rotor, because of the narrow cap, sticking occurs on the outer peripheral surface, and the sticking substance is detached and mixed into the coarse grain side (product side).
2. ) In the case of the classification chamber, the toner retention time becomes unstable due to toner adhesion, and the classification accuracy is lowered.
3. ) In the case of coarse grain (product) outlets, when adhesion progresses, it becomes impossible to discharge, and the operation stops due to overloading of the classification rotor.
4). ) In the case of a coarse particle-discharge ring, adhering toner accumulates, fusion occurs, and operation is stopped.
5. ) In the case of a spiral member, adhering toner accumulates, the classification accuracy due to a decrease in the inflow air flow rate is reduced, and the operation is stopped.

  As a technique for preventing such adhesion, a technique disclosed in Patent Document 2 is already known. Patent Document 2 discloses prevention of adhesion by coating using a fluororesin or other technique.

  In addition, in Japanese Patent Application Laid-Open No. 11-197607 of Patent Document 5, in an inertia classifier, a surface of a classification edge for determining a classification point is coated with a fluorine compound treatment after metal spraying. A method for producing toner for electrophotography using this classifier having a treatment layer is disclosed.

  However, the chromium alloy or fluorine compound containing chromium carbide of Patent Document 2 or Patent Document 5 has a higher resistance value than that of a metal (base material) and is less adhered to the inner surface of the device due to frictional charging with the powder. There was a difficulty that it progressed one by one and the anti-fusing effect decreased. Moreover, the strength of the coating surface is not sufficient, and there is also a problem that after use for a long time, it is necessary to disassemble, peel off and coat again.

Japanese Patent Laid-Open No. 10-118571 JP 2001-104888 A JP 2001-293438 A Japanese Patent Application No. 2005-216675 and drawings JP-A-11-197607

  Accordingly, an object of the present invention is to solve the above-described problems in the wind classifier of a mechanical centrifugal force type wind classifier (TSP; toner separator and TTSP; tandem toner separator), and to provide the mechanical centrifugal type wind force for a long period of time. It is an object of the present invention to provide a toner manufacturing facility and a manufacturing method that can secure a stable classification particle size without toner adhesion in a toner manufacturing facility machine including a classifier, and that can produce toner in a high throughput and a high yield.

  In the present invention, in the toner classification device used for electrophotographic toner production or the like, the pulling pressure of the outlet pipe of the classification device is lowered to the minus side of the classifier internal pressure, thereby eliminating adhesion on the discharge pipe. There is no toner adhering to the inside, and long-term operation is possible while ensuring a stable classification particle size. The classifying device herein includes a classifying rotor and one classifying chamber containing the classifying rotor including one or two coaxially arranged classifying chambers.

As a means to lower the suction pressure of the outlet pipe of the classification device to the minus side of the classifier internal pressure, the suction pressure in the discharge pipe increases by connecting a hose etc. to the outlet pipe and suctioning, and the toner classified in the classifier Is smoothly discharged to the outlet pipe, so that good results for preventing toner adhesion can be obtained efficiently.

That is, the above-mentioned problem is that the negative static pressure at the outlet pipe of the impeller type classifier (commonly known as TSP, TTSP (toner separator, tandem toner separator)) and the classifier outlet of the present invention Toner classifier that is related to outlet pipe internal pressure ",
(2) “Classifying device according to (1) above, wherein suction is performed by suction means such as a blower provided with a suction hose in an outlet pipe of the impeller type classifier (TSP, TTSP)”,
(3) "The classification device according to (1) or (2), wherein the suction hose is connected to the fine powder take-out chamber side",
(4) "The classification device according to any one of (1) to (3), wherein the suction hose is connected to a raw material inlet";
(5) The connection state between the suction hose and the outlet pipe is any one of the items (1) to (4), wherein at least the direction of the suction portion is connected to the product discharge side. Classification device described in "
(6) "The classification device according to any one of (1) to (5), wherein an inner diameter of the suction hose is φ2 to φ30 mm",
(7) The item (1) to (6), wherein the suction hose is provided with a flow rate adjusting valve, and the outlet pipe internal pressure is -1 to -20 Kpa suction pressure with respect to the classifier outlet internal pressure. This is achieved by the classifying device described in any of the above.
In addition, the above-mentioned problem is (8) “a toner manufacturing method having a classification step, and an outlet pipe and an outlet of the classifier of an impeller type classifier (commonly called TSP, TTSP (toner separator, tandem toner separator)). Toner production method characterized by using a classifier whose negative static pressure is in a relationship of classifier outlet internal pressure <outlet pipe internal pressure ",
(9) “Toner manufacturing method as described in (8) above, wherein suction is performed by suction means provided with a suction hose in an outlet pipe of the impeller type classifier (TSP, TTSP)”,
(10) “The toner manufacturing method according to (8) or (9) above, wherein the hose is connected to the fine powder take-out chamber side”;
(11) “The toner manufacturing method according to any one of (8) to (10) above, wherein the hose is connected to a raw material inlet”;
(12) Any one of (8) to (11) above, wherein the connection state between the suction hose and the outlet pipe is such that at least the direction of the suction portion is connected to the product discharge side. Toner production method described in "
(13) “The toner manufacturing method according to any one of (8) to (11) above, wherein an inner diameter of the suction hose is φ2 to φ30 mm”,
(14) The items (1) to (6), wherein the suction hose is provided with a flow rate adjusting valve, and the outlet pipe internal pressure is -1 to -20 Kpa suction pressure with respect to the classifier outlet internal pressure. The toner production method according to any one of the above.

  As will be apparent from the following detailed and specific description, it has been found that using the classification device according to the present invention, there is no toner adhesion in the device, and a stable classification particle size can be secured. The present invention provides a toner manufacturing facility that can stably perform desired processing such as ensuring a classified particle size without toner adhesion in the apparatus for a long period of time, and can produce toner in high throughput and high yield.

  In the toner manufacturing method of the present invention, high-quality toner can be stably manufactured as a result of being able to perform high-quality processing in the manufacturing apparatus portion according to the present invention. In addition, it is possible to save labor for maintenance in the apparatus part, and to achieve an extremely excellent effect that leads to cost reduction.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 2 is a partially broken perspective view showing a schematic configuration of an embodiment of a mechanical centrifugal force classifier (TSP; toner separator) according to the present invention, and FIGS. 3 to 8 are TTSP (tandem toner) according to the present invention. FIG. 3 is a partially broken perspective view showing the schematic configuration of the TTSP type toner classifier, and FIG. 5 is the TTSP type toner. FIG. 6 is a partially broken view showing the internal structure of the TTSP type toner classifier, and FIG. 7 is an example of the characteristic part of the present invention in the case of the classifier. FIG. 8 is a detailed view showing an example of another feature of the present invention.

[First Embodiment; TSP]
The mechanical centrifugal type wind power toner classifier (TSP; toner separator) of FIG. 2 has a basic structure as disclosed in Japanese Patent Application Laid-Open No. 2001-104888 of Patent Document 2 in an easily understandable manner. Based on the description of Patent Document 2, the structure of the main part of the present invention in the case of this type of classifier will be described (the reference numerals (601 to) in the figure represent the last two digits in [Patent Document 2]. It is attached in correspondence with the code). As described above, this type of toner classifier performs classification by balancing the centrifugal force by the blades provided on the rotating rotor and the centripetal force by the fan suction force.

  This vertical axis type air classifier is arranged vertically in a casing (601), a cylindrical classification rotor (602) housed above the casing (601), and below the classification rotor (602). A cylindrical drive shaft (603), a classification rotor support member (604) that connects the upper end of the drive shaft (603) and the lower end of the classification rotor (602) and vertically supports the lower end of the classification rotor (602), and classification A guide vane ring (605) is provided coaxially with an interval on the outer side in the radial direction of the classification rotor (602) with respect to the outer peripheral surface of the rotor (602). The classification rotor (602) includes a distribution disk (606) as a top wall, and a cover disk (607) as a bottom wall that is spaced vertically below the distribution disk (606). The distribution disk (606) and the classification blade ring (608) disposed between the peripheral edges of the cover disk (607). In this vertical axis type air classifier, in order to facilitate cleaning, the distribution disk (606), the cover disk (607), and the classification blade ring (608) can be disassembled with screws or the like. Although it is fixed, it may be fixed so that it cannot be disassembled by welding or the like. When the distribution disk (606) rotates, the classified raw material (raw material toner powder) fed through the raw material charging port (615) provided in the casing cover (614) is uniformly distributed over the entire circumference. It is formed as follows. A hole (606a) for inserting a tool for attaching and detaching the screw (611) is provided at the center of the distribution disk (606), and a screw groove is formed on the inner peripheral surface of the hole (606a). A cap screw (609) is screwed.

  The classifying blade ring (608) is composed of a plurality of classifying blades extending in the vertical direction and arranged in an annular manner at equal intervals along the peripheral edges of the classifying disk (606) and the cover disk (607). The cross-sectional shape and direction of the slit-shaped gap (S) formed between two adjacent classification blades (608a) and (608b) are shown in FIGS. The cross-sectional shape is set to be a shape suitable for the flow of classified air.

  A through hole (610) is provided at the center of the cover disk (607), and the classification rotor support member (604) is fixed to the lower surface of the cover disk (607) around the cover hole. The classification rotor support member (604) is detachably fixed to the upper end of the drive shaft (603) by a screw (611). The classifying rotor support member (604) includes a circular top plate (623) and a plurality of interval webs (625) extending vertically downward with respect to the top plate (623).

  A plurality of screw holes arranged at equal intervals in the circumferential direction are provided in the peripheral portion of the top surface of the top plate (623), and the top plate (623) is a screw that is screwed into the screw holes. It is detachably fixed to the lower surface of the classification rotor (602) via (not shown). A circular through hole (626) is formed concentrically on the top plate (623), and the through hole (626) formed in the cover disk (607) of the classification rotor (602) ( 610), the inside of the classification rotor support member (604) and the inside of the classification rotor (602) are in communication. The diameter of the through hole (610) is smaller than the diameter of the through hole (626), thereby forming a shielding part having a throttle action.

  This makes it difficult for the air inside the classification rotor (602) to flow into the classification rotor support member (604), and the air density inside the classification rotor (602) becomes somewhat higher, so it flows into the classification rotor (602). The flow of the classification air to be further suppressed is suppressed, and the coarse powder toner hardly flows into the classification rotor (602). Moreover, since the air which flows into the classification rotor support member (604) inside is accelerated, discharge | emission of the fine powder inside a classification rotor support member (604) is accelerated | stimulated.

  The spacing web (625) is annularly arranged at equal intervals along the periphery of the top plate (623) and the bottom plate (624), and the cross-sectional shape and orientation thereof are two spacing webs ( 625) and (625) so that the cross-sectional shape of the slit-shaped gap formed between them becomes a shape suitable for the flow of air discharged from the classification rotor support member (604), for example, FIG. It has a shape corresponding to the cross-sectional shape of the classification blade (608a) as shown in (E).

  The opening ratio of the gap formed between the spacing webs (625) and (625) with respect to the outer peripheral surface of the peripheral wall of the classification rotor support member (604) is preferably 20% or more. The opening ratio is preferably equal to or higher than the opening ratio of the gap between the classification blade rings (608) and (608) on the outer peripheral surface of the classification rotor (602). Further, the drive shaft (603) is supported on the lower end side so as to be rotatable around the center line, and the lower end portion is connected to a rotation shaft of a drive motor (not shown).

  The guide blade ring (605) is arranged in an annular shape at equal intervals in a direction parallel to the circumferential direction of the outer peripheral surface of the classification rotor (602), and extends in a plurality of vertical directions fixed to the casing (601). It is composed of blades. The cross-sectional shape and direction of the guide vanes are such that the cross-sectional shape of the slit-shaped gap formed between two guide vanes adjacent to each other is a shape suitable for the flow of classified air, for example, FIG. It has a shape corresponding to the cross-sectional shape of the classification blade (608a) as shown in (E).

  The casing (601) has an opening (613) for inserting and removing the classification rotor (602) on the upper surface, and a casing cover (614) is detachably attached to the opening (613). A raw material inlet (615) is provided at the center of the casing cover (614). Inside the casing (601), an annular classification air supply chamber (616) arranged coaxially outside the guide vane ring (605), and coaxially with the drive shaft (603) below the classification rotor (602). An annular fine powder discharge chamber (617) arranged in a shape and an annular coarse powder toner discharge chamber (618) arranged coaxially with the drive shaft (603) are provided outside the fine powder discharge chamber (617). ing.

  The classification air supply chamber (616) has a rectangular cross section with an open inner peripheral surface, and communicates with the classification space (612) through a gap between a plurality of guide blades constituting the guide blade ring (605). Yes. A classification air supply pipe (619) for taking in classification air from the outside is connected to the classification air supply chamber (616).

  The fine powder discharge chamber (617) is connected to the inside of the classification rotor (602) through the interval web (625) provided in the classification rotor support member (604) and the through hole (610) provided in the cover disk (607). Communicate. The fine powder discharge chamber (617) is connected to a fine powder discharge pipe (660) as a fine powder outlet for discharging the internal fine powder to the outside.

  The coarse toner discharge chamber (618) is located below the classification space (612) and communicates with the lower end of the classification space (612). The coarse powder toner discharge chamber (618) is connected to a coarse powder toner discharge pipe (621) serving as a coarse powder toner outlet for discharging the internal coarse powder toner to the outside.

  A seal portion (622) is provided between the lower surface of the classification rotor (602) and the casing (601). The seal portion (622) is constituted by the entire peripheral portion of the lower surface peripheral edge portion of the cover disk (607) and the upper surface annular portion of the casing (601) concentrically facing this, and there is a minute amount between them. A gap is formed. By this seal portion (622), the fine powder discharge chamber (617) is sealed to the classification space (612) and the coarse powder toner discharge chamber (618).

  Inside the classification space (612), a spiral spiral member (627) for controlling the residence time and aggregation of the classified objects in the classification space (612) is arranged coaxially with the classification rotor (602). ing. The spiral member (627) is a band-shaped member formed in a spiral shape, is fixed to the inner peripheral portion of the guide blade ring 5, and extends over almost the entire length of the classification space (612) in the height direction. A minute gap is formed between the inner periphery of the spiral member (627) and the outer periphery of the classification blade ring (608).

  By selecting the gradient of the spiral member (627), the residence time of the classification object can be adjusted. That is, increasing the gradient shortens the residence time, and decreasing the gradient increases the residence time.

  In addition, the gradient of the spiral member (627) can be variously changed in the height direction of the classification blade ring (608). If it does in this way, the residence time of a to-be-classified object will be variously adjusted to the height direction of a classification blade ring (608). For example, the gradient is increased at the portion facing the upper portion of the classification blade ring (608) so that the classification object is drawn quickly, and at the portion facing the central portion in the height direction of the classification blade ring (608), the gradient is increased. The retention time of the classification object is lengthened by reducing it, and the gradient is increased at the portion facing the lower part of the classification blade ring (608) so that the classification object is quickly discharged.

  Control of the aggregation of the objects to be classified can be performed by changing the number of spiral members (627). The spiral member (627) does not necessarily have to extend over the entire length in the height direction of the classification blade, and may be provided in a part in the height direction of the classification blade.

  An annular coarse toner discharging member (628) is provided concentrically inside the coarse toner discharge chamber (618). The coarse toner discharging member (628) has an L-shaped cross section formed along the inner side surface and bottom surface of the coarse toner discharge chamber (218), and the upper end thereof is a cover disk of the classification rotor (602). (607) and rotate integrally with the classification rotor (602). As a result, the coarse toner in the coarse powder discharge chamber (218) is fluidized, and the discharge from the coarse powder discharge chamber (218) is promoted.

  Between the inner side surface and the bottom surface of the coarse powder toner discharge chamber (618) and the coarse powder toner discharge member (628), a gap is formed for passage of cleaning air described later. The coarse powder toner discharging member (628) does not necessarily have to be formed in an annular shape so as to exist over the entire circumference of the coarse powder toner discharge chamber (618), and the circumferential direction of the coarse powder toner discharge chamber (618). It may be formed so as to exist only in a part of the. Further, the shape is not limited to the above shape.

  The casing (601) has an air passage (629) for introducing cleaning air into a gap formed between the lower surface of the classification rotor (602). The upper end of the air passage (619) is in communication with an annular air chamber (C) formed between the lower surface of the classification rotor (602) and the casing (601), and is supplied to the air chamber (C). Air flows into the coarse powder discharge chamber (618) through a minute gap between the lower surface of the classification rotor (602) and the casing (601), and further, the coarse powder discharge member (628) and the coarse powder discharge chamber (618). ) To the coarse powder discharge pipe (621) and discharged to the outside. Thereby, the coarse powder between the inner side surface and bottom surface of the coarse powder discharge chamber (618) and the coarse powder discharge member (628) can be removed.

  The cleaning air flows into the fine toner discharge chamber (617) through a minute gap between the lower surface of the classification rotor (602) and the casing (601), so that clogging and adhesion of the fine toner in the gap are prevented. can do. A cylindrical pressing ring (630) is coaxially disposed above the inside of the coarse toner discharge chamber (618), and the pressing ring (630) is fixed to the casing (601). The press ring (630) prevents the coarse toner in the coarse toner discharge chamber (618) from flowing back into the classification space (612).

  The operation of this classifier will be described. The classification air is supplied to the classification air chamber (616) via the classification air supply pipe (619), and this classification air passes through the gap formed in the guide vane ring (605) and enters the classification space (612). And flows into the rotating classification rotor (602) through a gap formed in the classification blade ring (608). To-be-classified toner introduced through the raw material introduction port (615) is dispersed in the entire circumferential direction by the distribution disk (606) of the classification rotor (602) and flows into the classification space (612).

  The classified toner flowing into the classification space (612) moves downward along the upper surface of the spiral member (627). Then, while the classified coarse toner passes through the classification space (612), the toner fine powder having a small particle diameter rides on the classification air flow and flows into the classification rotor (602), and is changed downward in the axial direction together with the classification air flow. Then, the air flows into the classification rotor support member (604) through the through hole (610) formed in the cover disk (607). The fine toner flows into the fine toner discharge chamber (617) through the gap between the gap webs (625) and (625) and is discharged to the outside through the fine toner discharge pipe (660).

  On the other hand, the coarse powder toner that has not been applied to the classified air flow in the classification space (612) descends in the classification space (612) along the spiral member (627) and is received by the coarse powder toner discharge chamber (618). The coarse toner is fluidized by the coarse powder discharge member (628) and discharged to the outside through the coarse powder discharge pipe (621).

  However, it cannot be said that the acceleration of the air flowing into the classification rotor support member (604) is sufficient, and therefore the discharge of fine powder inside the classification rotor support member (604) is not sufficiently promoted.

[Second Embodiment; TTSP (1)]
Next, as described above, for example, an impeller-type classifier known as TTSP (tandem toner separator) is known, and FIGS. 3 and 4 show an example of the present invention in the case of this type of classifier. Indicates. The centrifugal force type wind toner classifier (TTSP) shown in FIGS. 3 and 4 has a basic structure as disclosed in Japanese Patent Laid-Open No. 2001-293438, which is disclosed in Patent Document 3. In accordance with the description of Patent Document 3, the present invention in the case of this type of classifier will be described focusing on the structure of the main part.

  As described above, the classifier TTSP shown in FIGS. 3 and 4 has a plurality of impeller rotors on the same axis in one casing, and each classifying rotor has the same or different rotational speed. It is possible to entertain and classify a plurality of stages corresponding to each classifying rotor at the same time, and form a minute fluid space in the axial direction between the end portions of each classifying rotor facing each other.

  The classifier (1) of FIG. 3 consists of a casing that can be divided and pivoted via a hinge (2), which comprises an upper casing half (3) and a lower casing half ( 4), and classifying rotor (5) and classifying rotor (9) are accommodated respectively. FIG. 4 shows a state where the casing halves are closed, and FIG. 4 shows a state where the casing halves are opened. The classification rotor (5) has a drive shaft (7) rotatably fitted in the bearing portion (6) in the upper casing half (3). The classification rotor (5) is driven by a drive motor (8), and this drive motor (8) is connected to the classification rotor (5) via a drive shaft (7).

  Similarly, in the lower casing half (4) facing the upper casing half (3) coaxially, the classification rotor (9) has a drive shaft (10) whose bearing shaft (11). ) Is rotatably fitted. The classification rotor (9) is driven by a drive motor (12), and this drive motor (12) is connected to the classification rotor (9) via a drive shaft (10).

  Each of the classification rotors (5) and (9) is a classification rotor that is supported on one side, and each of the drive shafts (7) and (10), the particulate toner extraction chambers (14) and (13), and a bearing portion. (6) and (11) have cover discs (16) and (15) closed on the same side. Coarse grain-discharging rings (centrifugal rings) (28) and (29) are disposed on the axially outer sides of the classification rotors (5) and (9), respectively (see FIG. 5).

  A short pipe (17) is arranged above the classification rotor (5), and the raw material toner (T) to be classified is fed from one place in the circumferential range through the short pipe (17). The An outlet short tube (coarse grain outlet) (18) for coarse particles is arranged below the classification rotor (9). Reference numerals (13) and (14) denote fine powder discharge ports provided on the upper and lower sides in the axial direction. The supply of the classification air is performed via the classification air supply sections (19) and (20) opened on both tangential sides on the circumferences of the classification rotors (5) and (9).

  The classifying rotors (5) and (9) are arranged coaxially and confrontingly in the classifier (1), and the respective cover disks (16) and (15) are parallel to each other at intervals. In a flat plane. In this state, the classification rotors (5) and (9) rotate in the same direction. And it can classify | categorize into a fine particle thing and a coarse-grained object by adjusting the rotation speed of a classification rotor (5) and (9) equally. Further, by adjusting the rotation speeds of the classification rotors (5) and (9) to be different, for example, fine particles are removed from the fine particle take-out chamber (14), and intermediate particles are taken from the fine particle take-out chamber (13). The coarse particles can be taken out from the outlet short pipe (18). The classifying rotors (5) and (9) may be configured to rotate in opposite directions. A flow space (B) is formed between the cover disks (16) and (15).

  This classifier (1) has a cylindrical classification space (classification chamber) (26) in contact with the outer peripheral surfaces of the classifying rotors (5) and (9), spaced apart from the outer surface of the classifying rotor in the radial direction. In addition, a spiral member (27) is provided on an annular member (vane ring) arranged coaxially with the classification rotor (5) (9) (the spiral member for the classification rotor (9) is shown in FIG. 3). Although omitted in FIG. 5, it may of course be provided as shown in FIG. The spiral member (27) is a member for controlling the residence time and aggregation of the classification object in the classification space (26). The spiral member is formed as a vane ring by forming a band-shaped member in a spiral shape. It is fixed to the inner periphery of 3) and / or (4) and extends in the height direction of the classification space (26). A minute gap is formed between the inner periphery of the spiral member (27) and the outer periphery of the classification blade interval (8).

  A flow space is formed between the cover disks (16) and (15). This flow space is a detailed view of a portion A surrounded by a one-dot chain line in FIG. In FIG. 5B, reference numeral (g) indicates toner particles to be classified, which fall downward along the outer circumferences of the classification rotors (5) and (9). At this time, the air in the flow space rotates as indicated by the arrow (B) by the rotation of the classification rotors (5) and (9) and the respective cover disks (16) and (15). Extruded outward near the walls of the cover disks (16) and (15), where the toner particles (g) to be classified are drawn and carried into the flow space for dispersion.

FIG. 4 is a view showing an open state of the splitable casing by opening and turning, and FIG.
Shows a state of starting to open, and FIG. 5B shows a state of opening completely.

  As understood from FIG. 5, the classifier (1) has two blades supported on one side in one casing (3), (4) and driven by motors (8), (12). It has a car type classification rotor (5), (9). Each of the coaxial classification rotors (5), (9) has a cover disk (15), (16) closed at its first axial end, and its axial second At the end, it has a mechanism for taking out fine particles or medium particles.

  Between the end portions of the classifying rotors (5) and (9) facing each other, the first end portions of both of the classifying rotors are arranged so that the end faces face each other, forming a minute flow space in the axial direction. A small flow space is formed in the axial direction.

  The impeller type classification rotors (5) and (9) each have one tangential direction classification air supply part (19) and (20), and this classification air supply part is arranged at the height of each classification rotor. Furthermore, it has a classified product supply unit (17), a coarse classified product take-out mechanism (18), and a classification region.

  Through this classification area, the toner to be classified flows in the direction of the axial extension of the classification rotor. The classifying rotors (5) and (9) can be set with the same or different rotational speeds, and a plurality of stages corresponding to the classifying rotors can be classified simultaneously.

  That is, the classifier (1) shown in the figure is composed of a casing that can be divided and opened and turned in the direction of an arrow (R) via a hinge (2), and this casing has an upper casing half (3). ) And the lower casing half (4) and accommodates the classification rotors (5) and (9), respectively. In the figure, the casing half is closed. The classification rotor (5) has a drive shaft (7) rotatably fitted in the bearing portion (6) in the upper casing half (3). The classification rotor (5) is driven by a drive motor (8), and this drive motor (8) is connected to the drive shaft (7) and the classification rotor (5) via a transmission mechanism (8 ').

  Similarly, in the lower casing half (4), which faces the upper casing half (3) in a coaxial manner, the classification rotor (9) has its drive shaft (10) as a bearing portion (11). ) Is rotatably fitted. The classification rotor (9) is driven by a drive motor (12), and this drive motor (12) is connected to the drive shaft (10) and the classification rotor (9) via a transmission mechanism (12 ').

  Each of the classification rotors (5) and (9) is a classification rotor that is supported on one side. (6) and (11) are arranged symmetrically outward in the axial direction (upper and lower ends). In addition, closed cover disks (16) and (15) are provided on the opposite sides (axially central side). Coarse grain-discharge rings (centrifugal rings) (28) and (29) are disposed on the axially outward sides of the classification rotors (5) and (9), respectively.

  A short pipe (17) is arranged on the upper side of the classification rotor (5), and the granular material (T) (raw material) to be classified through this short pipe (17) is one place in the circumferential range. It is charged from. An outlet short pipe (coarse (product) discharge port) (18) for coarse particles is arranged below the classification rotor (9). Reference numerals (13) and (14) denote fine powder discharge ports provided on the upper and lower sides in the axial direction. The supply of the classification air is performed via the classification air supply sections (19) and (20) opened on both tangential sides on the circumferences of the classification rotors (5) and (9).

  The classifying rotors (5) and (9) are arranged coaxially and confrontingly in the classifier (1), and the respective cover disks (16) and (15) are parallel to each other at intervals. In a flat plane. In this state, the classification rotors (5) and (9) rotate in the same direction. And it can classify | categorize into a fine particle thing and a coarse-grained object by adjusting the rotation speed of a classification rotor (5) and (9) equally. Further, by adjusting the rotation speeds of the classification rotors (5) and (9) to be different, for example, fine particles are removed from the fine particle take-out chamber (14), and intermediate particles are taken from the fine particle take-out chamber (13). The coarse particles can be taken out from the outlet short pipe (18). The classifying rotors (5) and (9) may be configured to rotate in opposite directions. A flow space (B) is formed between the cover disks (16) and (15).

  This classifier (1) has a cylindrical classification space (classification chamber) (26) in contact with the outer peripheral surfaces of the classifying rotors (5) and (9), spaced apart from the outer surface of the classifying rotor in the radial direction. The spiral member (27) is provided on the annular member (vane ring) arranged coaxially with the classifying rotor (5) (9) (the spiral member for the classifying rotor (9) is shown in FIG. Although omitted in FIG. 5, it may of course be provided as shown in FIG. The spiral member (27) is a member for controlling the residence time and aggregation of the classification object in the classification space (26). The spiral member is formed as a vane ring by forming a band-shaped member in a spiral shape. It is fixed to the inner periphery of 3) and / or (4) and extends in the height direction of the classification space (26). A minute gap is formed between the inner periphery of the spiral member (27) and the outer periphery of the classification blade ring (8).

As shown in FIGS. 7 and 8, in this embodiment, suction hoses (13) and (14) are provided in the fine powder discharge ports (13) and (14) respectively provided on the upper and lower sides in the axial direction of the classifier configured as described above. 30), connected to the fine powder pipe (31), and provided with a flow rate adjusting valve (32). The suction hose or the like need not be connected to the fine powder pipe if the negative static pressure can maintain the relationship of the classifier outlet internal pressure <the outlet pipe internal pressure. For example, the same effect can be obtained even if a suction means such as a method of connecting to the raw material charging hopper or a blower device that sucks only the suction hose is provided.

  In the present embodiment, the suction pipe (35) is provided with a suction hose (30) or the like so that the negative static pressure has a relationship of classifier outlet internal pressure <exit pipe internal pressure, thereby eliminating toner retention at the classifier outlet. And the toner becomes difficult to adhere.

  Of course, the suction hose described above may be connected to the outlet pipe in a direction perpendicular to the outlet pipe, but in this embodiment, the suction port direction is attached to the discharge hole side in consideration of the improvement of the yield rate. (See Figure 8)

  Next, the effects of the above-described embodiment will be described below using examples. First, in order to confirm the effect of the present invention, a method for evaluating the excess of adhesion of granular materials and the yield of classified products will be described below. The particle size distribution is measured by the Coulter method. Examples of the measuring device for the particle size distribution of toner particles by the Coulter counter method include Coulter Counter TA-II and Coulter Multisizer II (both manufactured by Coulter).

The measurement method is described below.
First, 0.1 to 5 ml of a surfactant (preferably alkylbenzene sulfonate) is added as a dispersant to 100 to 150 ml of an aqueous electrolytic solution. Here, the electrolytic solution is a solution prepared by preparing a 1% NaCl aqueous solution using primary sodium chloride. For example, ISOTON-II (manufactured by Coulter) can be used. Here, 2 to 20 mg of a measurement sample is further added. The electrolytic solution in which the sample is suspended is subjected to a dispersion treatment with an ultrasonic disperser for about 1 to 3 minutes, and the measurement device is used to measure the volume and number of toner particles or toner using a 100 μm aperture as an aperture Volume distribution and number distribution are calculated. From the obtained distribution, the weight average particle diameter (D4) and the number average particle diameter of the toner can be obtained.

As channels, 2.00 to less than 2.52 μm; 2.52 to less than 3.17 μm; 3.17 to less than 4.00 μm; 4.00 to less than 5.04 μm; 5.04 to less than 6.35 μm; 6 Less than 35 to 8.00 μm; less than 8.00 to less than 10.08 μm; less than 10.08 to less than 12.70 μm; less than 12.70 to less than 16.00 μm; less than 16.00 to less than 20.20 μm; Uses 13 channels of less than 40 μm; 25.40 to less than 32.00 μm; 32.00 to less than 40.30 μm, and targets particles having a particle size of 2.00 μm to less than 40.30 μm.

<Example of toner production>
Binder resin: Polyester resin 100 parts by weight Charge control agent: 3,5-di-t-butylsalicylic acid zinc salt 2 parts by weight Release agent: Carnauba wax 3 parts by weight Colorant: C.I. I. Pigment Yellow 180 5% by weight
The mixture of the above materials was melt-kneaded with a biaxial kneader, cooled and solidified, and then coarsely pulverized to prepare a toner raw material. 500 kg of this toner raw material was pulverized by a jet mill to obtain a test pulverized product having a weight average particle diameter of 5.08 μm and 4 μm or less of 58.3% by number.
D4 (weight average diameter) / D1 (number average diameter) was 1.32.

  The initial conditions of the pulverized product to be tested were set so that D4 (weight average diameter) / D1 (number average diameter) of the classified product was 1.20. In Example 1 and Comparative Example 1, TTSP was used. 200 kg of pulverized material is continuously processed under the conditions of a rotor peripheral speed of 60 m / sec and an input amount of 60 kg / hour for each of a case where a hose is connected to a classifier outlet pipe according to the present invention and a case where suction is not performed and Regarding the adhesion status, the following a. ~ G. Was evaluated.

I. Whether or not the outer surface of the classification rotor is stuck b. Coarse state of coarse grain (product) outlet c. Coarse-grained material-discharge ring adhesion d. Adhered state of spiral member e. Yield of classified product D4 / D1 of the classified product at the end of 200kg continuous processing and 10kg processing
G. At the end of continuous 200kg treatment, 4μm or less content of classified product at 10kg treatment

  Table 1 summarizes the evaluation results for Example 1 and Comparative Example 1, respectively.

<Image output example 1>
Further, 0.2 parts by weight of silica fine particles and 0.2 parts by weight of titanium oxide were added to 100 parts by weight of the classified product obtained in Example 1, mixed with a Henschel mixer, and passed through a sieve to obtain toner A.
Two-part developer A was prepared by mixing 5 parts by weight of this toner A and 95 parts by weight of a silicon-coated carrier having a weight average diameter of 60 μm with a turbula mixer.
When the two-component developer A was set in an IPSIO COLOR 8150 manufactured by Ricoh and an image was output, an extremely clear and smooth gradation image was obtained.

<Image output example 2>
Next, the classified product obtained in Comparative Example 1 was mixed with silica and titanium oxide in the same manner as in Image Output Example 1 to obtain Toner B. A two-component developer was prepared in the same manner as in image output example 1 and image output was performed in the same manner as in image output example 1. As a result, a sharper and rougher image was obtained as compared with image output example 1.

It is a block diagram which shows an example of a fine powder manufacturing system (toner manufacturing system). 1 is a partially broken perspective view showing a schematic configuration of an embodiment of a mechanical centrifugal force type air classifier (TSP; toner separator) according to the present invention. 3 to 8 are diagrams showing the configuration of an embodiment of a TTSP (tandem toner separator) type toner classifier according to the present invention, in which FIGS. 3 and 4 show the schematic configuration of the TTSP type toner classifier. FIG. 5 is a perspective view showing the internal structure of the entire TTSP type toner classifier, FIG. 6 is a partially broken view showing the internal structure of the TTSP type toner classifier, and FIG. FIG. 8 is an enlarged cross-sectional view showing an example of a characteristic part of the present invention in the case of the classifier, and FIG. 8 is a detailed view showing an example of another characteristic part of the present invention. 1 is a diagram illustrating a configuration of an embodiment of a TTSP (tandem toner separator) type toner classifier according to the present invention. FIG. FIG. 5 is another diagram showing the configuration of an embodiment of a TTSP (tandem toner separator) type toner classifier according to the present invention. FIG. 2 is a perspective view showing an internal structure of the entire TTSP type toner classifier according to the present invention. FIG. 3 is a partially broken view showing an internal structure of a TTSP type toner classifier according to the present invention. It is an expanded sectional view which shows one example of the characteristic part of this invention in the case of the classifier which concerns on this invention. It is detail drawing which shows one example of the other characteristic part of this invention.

Explanation of symbols

1 Classifier 2 Hinges 3 and 4 Casing half parts 5 and 9 Classifying rotors 6 and 11 Bearing parts 7 and 10 Drive shaft 8 Classifying blade interval 8, 12 Drive motors 8 'and 12' Transmission mechanism 13 and 14 Fine substance take-out chamber ( Fine powder outlet)
15, 16 Cover disc 17 Short tube (Classification part supply part)
18 Outlet short pipe (classification take-out mechanism, outlet piping)
19, 20 Classification air supply unit 26 Classification room (classification space, guide blade interval)
27 Spiral members 28, 29 Coarse particles-discharge ring 30 Suction hose 31 Fine powder discharge piping 32 Flow rate adjusting valve 33 Drain valve 34 Drain valve 35 Suction hose outlet piping installation 601 Casing 602 Classification rotor 603 Drive shaft 604 Classification rotor support member 605 Guide vane ring 606 Distribution disc (top wall)
606a Hole 607 Cover disc (bottom wall)
608 Classification blade ring 609 Screw 610 Cover disk through-hole 611 Screw 612 Classification space 613 Casing opening 614 Casing cover 615 Raw material inlet 616 Classification air supply chamber 617 Fine powder discharge chamber 618 Coarse powder discharge chamber 619 Classification air supply pipe 620 Fine powder discharge pipe (fine powder outlet)
621 Coarse powder discharge pipe (coarse powder outlet)
622 Sealing part 623 Top plate 624 Bottom plate 625 Spacer web 626 Through hole 627 Spiral member 628 Coarse toner discharging member 630 Holding ring 831 Grinding means 832 Classification means B Direction C Air chamber g Classification particles R Turning direction T Granular matter

Claims (14)

A toner classifier in which the negative static pressure at the outlet pipe of the impeller type classifier (commonly known as TSP, TTSP (toner separator, tandem toner separator) and the classifier outlet) has the relationship of classifier outlet internal pressure <outlet pipe internal pressure. The classifying apparatus according to claim 1, wherein suction is performed by suction means such as a blower provided with a suction hose in an outlet pipe of the impeller type classifier (TSP, TTSP). The classification device according to claim 1 or 2, wherein the suction hose is connected to the fine powder take-out chamber side. The classification device according to any one of claims 1 to 3, wherein the suction hose is connected to a raw material charging port. The classification device according to any one of claims 1 to 4, wherein the suction hose and the outlet pipe are connected such that at least the direction of the suction portion is connected to the product discharge side. 6. The classification device according to claim 1, wherein an inner diameter of the suction hose is φ2 to φ30 mm. The classifier according to any one of claims 1 to 6, wherein the suction hose is provided with a flow rate adjusting valve, and the outlet pipe internal pressure is -1 to -20 Kpa suction pressure with respect to the classifier outlet internal pressure. A toner manufacturing method having a classification step, wherein the negative static pressure at the outlet pipe of the impeller type classifier (commonly known as TSP, TTSP (toner separator, tandem toner separator)) and the outlet of the classifier is the classifier outlet internal pressure <outlet pipe internal pressure A toner manufacturing method using a classifier having the following relationship: 9. The toner manufacturing method according to claim 8, wherein suction is performed by suction means provided with a suction hose in an outlet pipe of the impeller type classifier (TSP, TTSP). The toner manufacturing method according to claim 8, wherein the hose is connected to the fine powder take-out chamber side. The toner manufacturing method according to claim 8, wherein the hose is connected to a raw material charging port. The toner manufacturing method according to claim 8, wherein the suction hose and the outlet pipe are connected such that at least the direction of the suction portion is connected to the product discharge side. The toner manufacturing method according to claim 8, wherein an inner diameter of the suction hose is φ2 to φ30 mm. The toner manufacturing method according to claim 1, wherein the suction hose is provided with a flow rate adjusting valve, and the outlet pipe internal pressure is −1 to −20 Kpa with respect to the classifier outlet internal pressure.

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