JP5871580B2 - Toner storage device and toner manufacturing method - Google Patents

Description

  The present invention relates to a storage device for suppressing defective discharge from a storage device that contains toner for developing an electrostatic charge image, and a toner manufacturing method using the storage device.

  A method of visualizing image information through an electrostatic charge image such as electrophotography is currently used in various fields. In the electrophotographic method, an electrostatic latent image is first formed on an image holding member by charging and exposure processes. Next, the electrostatic latent image is developed with a developer containing toner, and visualized through a transfer process and a fixing process. The developer used here includes a two-component developer comprising a toner and a carrier, and a one-component developer using a magnetic toner or a non-magnetic toner alone. The production methods of these toners are roughly classified into a dry production method and a wet production method, and the configurations of the production apparatus and the production method are greatly different.

  Examples of the dry production method include a pulverization method. In this production method, a colorant, a release agent, and the like are melt-mixed in a thermoplastic resin with a kneader or the like and uniformly dispersed. Further, the obtained melt-kneaded product is cooled and solidified, then finely pulverized by a fine pulverizer, and classified to obtain toner particles having a desired particle diameter. Thereafter, a predetermined additive is added to the toner particles to produce a toner.

  On the other hand, the wet manufacturing method is a method of forming toner particles in a liquid. Various toner particle production methods such as a suspension polymerization method, an emulsion polymerization method, a dissolution suspension method, and a dispersion polymerization method are implemented depending on the material constituting the toner particles and the desired toner particle shape. For example, in the suspension polymerization method, a polymerizable monomer composition containing a polymerizable monomer, a colorant, a release agent and the like is granulated and dispersed to a desired particle size in an aqueous medium. Further, it is a production method for obtaining toner particles by polymerizing a polymerizable monomer. Thereafter, solid-liquid separation is performed, and a predetermined additive is added to the dried toner particles to produce a toner.

  In any of these manufacturing methods, the manufacturing process or manufactured toner particles or toner (hereinafter, sometimes referred to as “toner” without distinguishing between “toner particles” and “toner”) is sent to the next process. In general, a storage device such as a hopper, a silo, a tank, or a bunker is used for temporary or long-term storage. The toner stored in these storage devices is discharged from the storage device after being stored for a necessary period and used, but defective discharge from the storage device is likely to occur due to adhesion to the storage device wall surface, bridges, ratholes, funnel flow, and the like. The reason why such a problem is likely to occur in the toner is that the toner obtained by the wet manufacturing method is in a wet state before being dried, and the adhesion to the inside of the storage device, bridging and ratholes are likely to occur. In addition, dry toner and dry-processed toner have characteristics that are required for toner and have a small particle size and are easy to be charged. However, bridging, funnel flow and the like due to compaction and electrostatic adhesion at the bottom of the storage device are likely to occur.

  Such defective discharge from the storage device not only causes a decrease in yield, but also causes a removal operation of the toner remaining in the storage device, resulting in a decrease in operating rate. Furthermore, continuing to use the storage device in which defective discharge has occurred leads to unintentional mixing in the production after the next lot, making it difficult to stably obtain toner of desired quality over a long period of time. In particular, when toner in a wet state obtained by a wet manufacturing method is mixed in the production after the next lot, the distribution of the triboelectric charge amount of the toner becomes broad, and the image density decreases or fogs under high temperature and high humidity conditions. Is likely to occur. In addition, dry toner and dry-process toner are also stressed by the friction caused by the input and output of toner in the storage device, and mixed in the subsequent lots, etc. It is difficult to obtain a toner having stable thermal characteristics.

  For this reason, various methods for preventing defective discharge have been proposed for storage devices used for toner production. For example, a vibration generating device such as a knocker or vibrator is attached to the storage device, a lining that hardly adheres toner to the inner wall surface of the storage device is used, or aeration is used to impart fluidity to the compacted toner.

  As an example of installing a vibration generator, placing the vibrating part in a suspended state in a container for temporarily storing powder prevents adhesion and aggregation in the storage device, smooth powder discharge and A technique for enabling supply is disclosed (see Patent Document 1). Also disclosed is a technique for removing toner particles adhering to the inner wall surface of a toner storage facility by shortening the impact interval applied to the toner storage facility when the impact is not manufactured compared to when the toner is manufactured. (See Patent Document 2).

  As an example of using a lining, a technique for preventing a low softening point toner from sticking is disclosed by using a toner manufacturing apparatus in which a toner contact portion is subjected to a surface lining treatment with a conductive plastic (see Patent Document 3). ).

  In addition, as an example of using aeration, a large number of fine holes for ejecting gas are provided at the bottom of the toner storage device, and the toner is fluidized by introducing pressurized gas into the fine holes, and the fixed amount discharge from the toner storage device. A technique for making this possible is disclosed (see Patent Document 4).

JP 2006-289349 A JP 2006-330183 A Japanese Patent Laid-Open No. 2004-279672 JP-A-2005-70249

  However, the techniques using the vibration generator as in Patent Documents 1 and 2 have an effect in the vicinity of the vibration generator, but the effect is small at a location away from the vibration generator. Furthermore, in the case of a powder having a small particle size such as toner, vibration may be applied, which may cause compaction at the bottom of the toner storage device and make powder discharge more difficult.

  Moreover, the technique using lining like patent document 3 is a technique for preventing wall surface adhesion, and it is difficult to suppress discharge | emission defects, such as a bridge | bridging in the storage apparatus bottom part. In particular, it is difficult to suppress the discharge failure of a powder that is easily compacted with a small particle size, such as toner, or toner in a wet state.

  In addition, the technique using aeration as in Patent Document 4 promotes fluidization at the bottom of the storage device, so that it is effective for compaction in dry powder, while the toner adheres to wet toner and wall surfaces. It is difficult to prevent this.

  As described above, it is difficult to solve the toner discharge failure from the toner storage device by the conventional technology. Such defective discharge from the storage device not only lowers the yield, but also causes the operation of removing the toner remaining in the storage device, leading to a reduction in operating rate. Furthermore, continuing to use the storage device in which defective discharge has occurred causes unintentional mixing in the production after the next lot, and it is difficult to stably obtain toner of a desired quality over a long period of time. In particular, when toner in a wet state obtained by a wet manufacturing method is mixed in the production after the next lot, the distribution of the triboelectric charge amount of the toner becomes broad, and the image density decreases or fogs under high temperature and high humidity conditions. Is likely to occur. Also, dry toner and dry-processed toner are stressed by friction due to toner input and discharge in the storage device, and are mixed in the next lot and later, causing heat such as toner image quality and anti-blocking properties. It becomes difficult to obtain a toner having stable characteristics.

  An object of the present invention is to suppress toner discharge failure in a storage device that stores toner. As a result, a toner storage device that can obtain toner with high yield and can obtain toner with stable image quality and thermal characteristics over a long period of time by preventing unintentional mixing in production after the next lot. And a toner manufacturing method using the toner storage device.

  The solution to the above problem is achieved by taking the following means.

A storage device for containing toner particles or toner,
The storage device
i) having an air-permeable flexible partition member on the inner periphery of the storage unit;
ii) having gas supply means for supplying gas between the inner wall surface of the storage unit and the partition member;
The partition member is
i) It is deformed by the gas supplied from the gas supply means, and the volume of the space formed between the inner wall surface of the storage device and the partition member is variable,
ii) Breathability is 0.2 cm ³ / cm ² · sec or more and 50.0 cm ³ / cm ² · sec or less,
This is a storage device.

  According to the present invention, it is possible to suppress toner discharge failure in a storage device that stores toner. As a result, a toner storage device that can obtain toner in a high yield and can obtain toner of stable quality over a long period of time by preventing unintentional mixing in production after the next lot, and the toner A toner manufacturing method using a storage device can be provided.

1 is a schematic cross-sectional view illustrating an example of a toner storage device according to the present invention. It is the schematic which shows the diagonal line of the twill weave cloth surface. It is the schematic which shows that the direction of the oblique line of two twill fabrics combined differs. It is the schematic shown about the subordinate angle and dominance angle which a diagonal line forms. It is the schematic which shows an example of a mode that three or more twill cloths were combined.

  The toner particles or the storage device (hereinafter also referred to as toner storage device) and the toner production method of the present invention can be used in a dry production method such as a pulverization method. Also, in a wet manufacturing method such as a suspension polymerization method, a toner formed in a liquid can be used after solid-liquid separation by filtration or the like.

  In these manufacturing methods, a storage device such as a hopper, a silo, a tank, or a bunker is generally used to store the manufactured process or the manufactured toner temporarily or for a long time until it is sent to the next process.

  The toner stored in the toner storage device is stored for a necessary period and then discharged from the storage device for use. However, due to adhesion to the storage device wall surface, bridges, ratholes, funnel flow, etc., defective discharge from the storage device is likely to occur. .

  In order to solve this problem, the present inventor has studied a mechanism that causes defective discharge from the toner storage device. As a result, the toner obtained by the wet manufacturing method is in a wet state before being dried, and compaction adhesion, bridging, and ratholes easily occur in the storage device. In addition, dry toner and dry-processed toner have characteristics that are required for toner and have a small particle size and are easy to be charged. However, bridging or funnel flow due to compaction or electrostatic adhesion at the bottom of the storage device is likely to occur. That is, in order to suppress the discharge failure from the storage device, it is considered important to provide a technology for imparting fluidity to the toner while suppressing adhesion to the wall surface of the storage device or adhesion due to charging.

  As a technique for suppressing adhesion to a wall surface, a technique for attaching a vibration generating device such as a knocker or vibrator to a storage device is generally known. The present inventor paid attention to this technology and examined it by attaching the vibration generator to the storage device. As a result, although the adhesion around the vibration generator can be suppressed, it is difficult to remove the adhesion at a place away from the vibration generator. Further, the fluidity is lost due to the consolidation of the toner due to vibration, which may cause further discharge failure. Therefore, in order to impart fluidity to the toner even when the vibration generator is attached, both the vibration generator and the aeration were installed in the storage device. As a result, although the dry toner has a certain effect on the compaction, it is difficult to remove the adhesion at a place away from the vibration generator. Further, it is difficult to fluidize the toner in a wet state by aeration, and the discharge failure cannot be solved.

  The present inventor further studied a technique for suppressing defective discharge from the storage device. As a result, a flexible partition member is installed on the inner peripheral portion of the storage device, and the partition member is discharged while being deformed, and the partition member is discharged while being ventilated using a member having a predetermined air permeability. It was found that the discharge failure can be solved by the technology to be performed.

  Hereinafter, although the form for implementing this invention is demonstrated in detail, this invention is not limited to this.

  The toner storage device and the toner production method of the present invention can be used in a dry production method such as a pulverization method. Also, in a wet manufacturing method such as a suspension polymerization method, a toner formed in a liquid can be used after solid-liquid separation by filtration or the like. Here, the suspension polymerization method will be described as a representative example.

  First, a release agent, a colorant, a charge control agent, a polymerization initiator, a crosslinking agent, and other additives are added to the polymerizable monomer, and uniformly dissolved or dispersed by a stirrer such as a homogenizer or an ultrasonic disperser. A polymerizable monomer composition is prepared. Next, droplets made of the polymerizable monomer composition are granulated to a desired toner particle size by an agitator having a high shearing force in an aqueous phase containing a dispersant. In the suspension polymerization method, it is usually preferable to use 100 to 3000 parts by weight of water as a dispersion medium with respect to 100 parts by weight of the polymerizable monomer composition. After that, since the particle state is maintained by the action of the dispersant, stirring may be performed to such an extent that the sedimentation of the particles is prevented. Polymerization is carried out at a polymerization temperature of 40 ° C. or higher, generally 50 to 90 ° C. to obtain a toner particle dispersion. When adding a polymerization initiator, even after preparing a polymerizable monomer composition, it can be carried out at an arbitrary time and required time. In addition, the temperature may be raised in the latter half of the polymerization reaction for the purpose of obtaining a desired molecular weight distribution. Further, in order to remove unreacted polymerizable monomers and by-products from the system, the latter half of the reaction or after the completion of the reaction. A part of the aqueous medium may be distilled off by distillation. The distillation operation can be performed under normal pressure or reduced pressure.

  As the polymerizable monomer used in the toner particles of the suspension polymerization method, a vinyl polymerizable monomer capable of radical polymerization is preferably used. As the vinyl polymerizable monomer, a monofunctional polymerizable monomer or a polyfunctional polymerizable monomer can be used. For example, styrene derivatives such as styrene and 2,4-dimethylstyrene, and acrylic polymerizable monomers such as n-butyl acrylate are preferably used. Other examples include methacrylic polymerizable monomers such as methyl methacrylate and vinyl esters such as vinyl acetate.

  A known colorant can be used as the colorant used in the suspension polymerization toner particles. For example, C.I. I. Direct Red 1, C.I. I. Direct Blue 1, C.I. I. Examples thereof include dyes such as basic green 6; pigments such as carbon black, mineral fast yellow, cadmium red, brilliant carmine 3B, and phthalocyanine blue.

  As the release agent used for the toner particles of the suspension polymerization method, a wax in a solid state at room temperature is preferable in terms of toner blocking resistance, durability of a large number of sheets, low-temperature fixability, and offset resistance. Examples thereof include paraffin wax, microcrystalline wax, Fischer-Tropsch wax, and ester wax. In order to improve the translucency of the image fixed on the OHP, a linear ester wax is particularly preferably used.

  The charge control agent used in the suspension polymerization toner can be externally added to the toner particles, but is added to the inside of the toner particles by dispersion in the polymerizable monomer composition or the like. It is also possible. Examples of the charge control agent imparting negative chargeability include organometallic compounds and chelate compounds. Examples of the charge control agent imparting positive chargeability include nigrosine and amine compounds.

  Examples of the polymerization initiator used for the suspension polymerization toner particles include potassium peroxodisulfate, hydrogen peroxide solution, 2,2′-azobis- (2,4-dimethylvaleronitrile), benzoyl peroxide, t-butylperoxide. Examples include oxylaurate.

  Examples of the crosslinking agent include polyfunctional compounds such as divinylbenzene, 4,4′-divinylbiphenyl, and ethylene glycol di (meth) acrylate.

  In addition, as a dispersion stabilizer for dispersing a polymerizable monomer composition in an aqueous medium in a suspension polymerization method, a water-soluble polymer that generally develops a repulsive force due to steric hindrance and an electrostatic repulsive force. They are roughly classified into poorly water-soluble inorganic compounds that aim to stabilize dispersion. The fine particles of the hardly water-soluble inorganic compound are preferably used because they are dissolved by an acid or an alkali and can be easily removed by washing with an acid or an alkali after polymerization. Among the hardly water-soluble inorganic compounds, metal phosphates are preferably used. Among these, alkaline earth metal phosphates such as calcium phosphate are preferable. For example, in the case of tricalcium phosphate, a dispersion stabilizer suitable for the suspension polymerization method can be obtained by charging and mixing a trisodium phosphate aqueous solution and a calcium chloride aqueous solution with sufficient stirring.

  In the case of a polymerization method using an aqueous dispersion medium such as suspension polymerization, the inclusion of a release agent can be promoted by adding a polar resin to the polymerizable monomer composition. When a polar resin is present in the polymerizable monomer composition in the aqueous medium, the polar resin moves to the vicinity of the interface between the aqueous medium and the polymerizable monomer composition due to the difference in hydrophilicity. Polar resin is unevenly distributed. As a result, the toner particles have a capsule structure having a core / shell structure, and even when a large amount of the release agent is contained in the core portion, the inclusion property of the release agent is improved.

  In addition, if a resin with a high melting temperature is selected for the polar resin used for the shell part, even if the binder of the core part is designed to be melted at a lower temperature for the purpose of fixing at low temperature, it may cause problems such as blocking during storage. Occurrence can be suppressed. As such a polar resin, since the fluidity of the polar resin itself can be expected when it is unevenly distributed on the surface of the toner particles to form a shell, a saturated or unsaturated polyester resin is particularly preferable.

  The toner particle dispersion thus obtained is sent to a solid-liquid separation / washing step. At that time, the toner particle dispersion can be solid-liquid separated in advance before the process and reslurried. The apparatus used there is not particularly limited as long as it is a known solid-liquid separation method, and examples thereof include a pressure dehydrator, a vacuum dehydrator, a screw press, a basket type centrifuge, and a decanter type centrifuge. Thereafter, solid-liquid separation is performed by a known solid-liquid separation method, and after sufficient washing, solid-liquid separation is performed again to obtain a toner cake. When solid-liquid separation / washing is performed, or before and after that, treatment with acid or alkali, bubbling, light irradiation, treatment with ozone, or the like can be performed as necessary.

  The obtained toner cake is dried by a known drying means, but is generally stored in a storage device temporarily before being sent to the drying process. A cross-sectional view of an example of a storage device according to the present invention is shown in FIG. However, the present invention is not limited to this.

  In FIG. 1, 1 is a toner storage device, 2 is a toner inlet, 3 is a toner outlet, 4 is a partition member, 5 is a partition member fixture, 6 is a gas supply path, and 7 is a gas supply path valve. .

  The toner storage device is not particularly limited as long as it is a container that can store toner without leaking outside, but a metal or resin silo, bunker, and hopper are preferably used. The toner storage device generally has a toner inlet 2 at the top and a toner outlet 3 at the bottom, but these locations can be changed as required. Further, a discharge promoting device such as a vibration generating device or an aeration device can be installed in the toner storage device as necessary. Furthermore, a discharge device such as a damper, a rotary valve, or a screw feeder can be installed in the discharge port 3.

  The toner storage device of the present invention includes a partition member 4 on the inner periphery of the storage unit. The partition member is fixed to the toner storage device by the partition member fixture 5. The part where the partition member is installed is not particularly limited as long as it is an inner peripheral part of the storage unit, but it is preferable to install the partition member over the entire surface where the toner may come into contact, and more preferably over the entire inner periphery of the toner storage device. It is preferable to install. It should be noted that the partition member fixing tool can be omitted when the partition member can be fixed by being sandwiched between the toner storage device and the upper lid. Further, when the partition member bends and hangs down, it can be fixed to the toner storage device with a partition member fixture as necessary.

The partition member used here is a flexible partition member that can be ventilated, and the breathability of the partition member is 0.2 cm ³ / cm ² · sec or more and 50.0 cm ³ / cm ² · sec or less. There is no particular limitation as long as it satisfies the requirements. The air permeability can be measured by a method defined by JIS L 1096 “Testing method for fabrics and knitted fabrics”. For example, “Fragile type air permeability tester AP-360S” (Daei Kagaku Seiki Seisakusho Co., Ltd.) Can be used.

  The air permeability used here roughly represents the opening of the partition member. Since the toner is a powder having a small particle diameter in terms of a required function, it is important to use a partition member having an appropriate air permeability. By supplying gas to the partition member with appropriate air permeability, it is possible to blow off the toner adhering to the upper part of the partition member, and at the lower part, the toner fluidization is promoted by the aeration effect and the discharge is promoted. Is done. If the air permeability of the partition member is too large relative to the particle size of the toner, the toner leaks from the partition member and adheres to the inner wall of the toner storage device, resulting in a decrease in yield and mixing into the product at an unintended time. . Furthermore, if the air permeability of the partition member is too small relative to the toner particle size, the air flow to the partition member is insufficient and the effect of removing the adhesion is reduced. Use is difficult. In the present invention, the air permeability of the partition member of the present invention can be applied to a toner having a weight average particle diameter of 3.0 μm or more and 10.0 μm or less, which is a general toner particle diameter. The weight average particle diameter of the toner can be measured by a pore electrical resistance method. For example, “Coulter Counter Multisizer 3” (manufactured by Beckman Coulter Co., Ltd.) and attached software “Beckman Coulter Multisizer 3 Version 3.51” (manufactured by Beckman Coulter Co., Ltd.) for measurement condition setting and measurement data analysis ) Can be used for measurement and calculation.

  In the present invention, by using a flexible partition member, the partition member can be deformed, and the adhered toner can be efficiently removed. As a means for deforming the shape of the partition member, in the present invention, a space is formed between the inner wall of the toner storage device and the partition member by supplying gas between the inner wall of the toner storage device and the partition member. This is achieved by making the volume of the variable variable.

  The amount of gas to be supplied can be arbitrarily set according to the size of the toner storage device, the amount of stored toner, the size of the partition member, and the like. Moreover, the gas supply method is not limited, and can be supplied by any method such as intermittent, continuous, simultaneous at a plurality of locations, or sequentially at a plurality of locations. In addition, when the toner is put into the toner storage device, the generation of dust can be suppressed by discharging the gas from the gas supply path. Furthermore, the kind of gas is not specifically limited, Air and nitrogen are preferably used, and you may perform heating, humidification / humidification, etc. as needed. Further, the supply and discharge of gas can be repeated as necessary, and the shape of the partition member can be changed using mechanical means.

  Examples of the partition member satisfying the above include, but are not limited to, natural material woven fabrics such as cotton and linen, resin woven fabrics such as polypropylene and polyester, nonwoven fabrics, glass cloths, and metal cloths. It is not something. Among these, natural material woven fabrics and resin woven fabrics are preferably used from the viewpoint of durability and weight. The method of weaving these woven fabrics is not particularly limited, and examples include twill weave, plain weave, and tatami weave. Among them, a twill weave is preferred because it has a high degree of flexibility because there are few crossing of the weaving yarns, and is difficult to fatigue-harden due to a large bending angle of the weaving yarns.

It is particularly preferable that the partition member is a conductive cloth for use in the toner storage device. The toner has a characteristic that it is easily charged from the viewpoint of a required function. Therefore, the toner may be charged and adhered due to friction with the partition member. When the partition member has conductivity, it is possible to prevent such charge adhesion. As the conductivity index, surface resistivity is used, and the surface resistivity is 10 ¹⁰ Ω / sq. The following is preferable. The surface resistivity can be measured with a commercially available surface resistivity meter. For example, “MODEL 152-1” (manufactured by Trek Japan Co., Ltd.) can be used. The means for imparting conductivity to the partition member is not particularly limited, and all the materials constituting the partition member may be conductive, or some of the materials may be conductive, or conductive to a non-conductive cloth. This may be achieved by adding material.

  Further, it is more preferable that the partition member is a combination of two or more twilled fabrics, and the inferior angle formed by the oblique lines of the adjacent fabrics is 30 ° or more and 150 ° or less. The oblique line is a line that appears characteristically on the surface of the twill weave as shown in FIG. The warp and weft yarns constituting the twill weave are not floated alternately, but are floated continuously, and this texture point becomes a diagonal line. This is called the oblique line (see “Maglow Hill Science and Technology Glossary 2nd Edition” (Nikkan Kogyo Shimbun), page 689). The twilled fabric is rich in flexibility and less fatigue hardened, and therefore can be suitably used as the partition member of the present invention. On the other hand, the weaving yarns are regularly arranged in the direction of the oblique pattern, and the number of intersections of the yarns is smaller than that of plain weaving and the like, so that the fabric easily stretches in one direction. For this reason, when the twilled partition member is used for a long period of time, the partition member extends in one direction, and the weave opens, causing toner to leak from the partition member. This is considered to be due to friction between the toner due to repeated supply and discharge of the toner and repeated collision with the gas when the gas is supplied between the storage device inner wall and the partition member. Therefore, in order to prevent the partition member from extending in one direction, it is preferable to use two or more twill cloths having different oblique line directions of adjacent twill cloths as a partition member (FIG. 3). ). Furthermore, the case where the inferior angle formed by the oblique lines of the adjacent twill cloth is 30 ° or more and 150 ° or less (FIG. 4) is particularly preferable, and the partition member can be used for a long period of time. Furthermore, three or more sheets can be combined to form a partition member in the form as shown in FIG. 5, and an arbitrary number of cloths can be combined in consideration of the cost of the connection. Further, the twill cloth can be joined by any means, for example, by stitching or fusion.

  Hereinafter, the present invention will be described in detail with reference to FIG. However, this is an example, and the present invention is not limited to this.

  The toner is introduced into the toner storage device 1 from the toner inlet 2. At this time, it is preferable to supply toner while exhausting from the gas supply path 6 because generation of dust can be suppressed. After being stored in the storage device for a necessary time, the toner is discharged from the toner discharge port 3. At the time of discharge, gas is supplied from the gas supply path 6, and all of the gas supply path valves 7 are sequentially opened as necessary. The gas supplied to the toner storage device changes the volume of the space formed between the inner wall surface of the toner storage device and the partition member 4, and the partition member 4 is deformed accordingly. Since the partition member can be ventilated, toner deposits are effectively removed by the deformation of the partition member and the effect of ventilation. The toner discharge may be performed while exhausting from the toner supply port 2 with a blower or the like, if necessary. Further, an air blow may be used in combination with the toner storage device. When the discharge proceeds and the remaining amount of toner decreases, the gas supply path valve 7 at the upper part of the toner storage device may be closed and only the lower gas supply path valve 7 may be opened as necessary. In the lower part of the storage device, in general, adhesion to a corner portion, bridging due to compaction, and funnel flow are likely to occur. In the present invention, since the shape of the partition member at the corner portion is changed, the adhesion of the corner is effectively removed, and the fluidization of the toner is promoted by aeration, so that bridge and funnel flow due to compaction hardly occur.

  The toner thus discharged from the storage device is dried by a known drying means. The dried toner is also stored in a storage device as necessary, but the storage device of the present invention can be preferably used.

  When necessary, the toner after drying separates a group of particles having a particle size outside the predetermined range by classification. The non-predetermined particle group separated at this time may be reused to improve the final yield. Furthermore, for the purpose of imparting various characteristics to the toner, other external additives may be externally added to the toner. The external additive preferably has a particle size of 1/10 or less of the average particle size of the toner from the viewpoint of durability when added to the toner. Examples of external additives include metal oxides such as aluminum oxide, nitrides such as silicon nitride, carbides such as silicon carbide, inorganic metal salts such as calcium sulfate, fatty acid metal salts such as zinc stearate, carbon black, silica, and the like. Is used. The toner thus obtained is filled in a toner bottle, a toner cartridge, a container or the like as necessary. Further, when used as a two-component developer, it may be sent to a mixing step with a carrier. In the case where it is necessary to store toner that has been classified or toner that has been externally added, the storage device of the present invention can be preferably used.

  The toner produced using the storage device of the present invention can be used for any developer, usually as a one-component or two-component developer. For example, as a one-component developer, in the case of a magnetic toner in which a magnetic substance is contained in toner particles, there is a method of conveying and charging the magnetic toner using a magnet built in the developing sleeve. When non-magnetic toner containing no magnetic material is used, there is a method of using a blade, a fur brush, or the like to forcibly charge by a developing sleeve and transport the toner by adhering the toner onto the sleeve. On the other hand, when used as a two-component developer, a carrier is used as a developer together with the toner of the present invention. The carrier is composed of a single and a composite ferrite state mainly composed of iron, copper, zinc, nickel, cobalt, manganese, and chromium elements. In general, a method in which carrier core particles are generated in advance by firing and granulating the above-mentioned inorganic oxide and then coating a resin is used. In addition, from the viewpoint of reducing the load on the toner of the carrier, the inorganic oxide and the resin are kneaded and then pulverized and classified to obtain a low density dispersed carrier, or the mixture of the inorganic oxide and the monomer is suspended in an aqueous medium. A method of obtaining a polymerization carrier by suspension polymerization can also be used.

  EXAMPLES Hereinafter, although this invention is demonstrated further in detail based on an Example, the embodiment of this invention is not limited to these. First, a method for evaluation performed in Examples will be described below.

(1) Measurement of yield in storage device The yield in the storage device is obtained by calculating the ratio of the mass of toner discharged from the storage device to the mass of toner charged in the storage device. That is, when the mass of the toner charged into the storage device is Akg and the mass of the toner discharged from the storage device is Bkg, the yield is calculated by the following equation.
Yield% = (B / A) × 100

(Evaluation criteria)
A: Very good level (yield 99.5% or more)
B: Good level (yield 99.0% or more and less than 99.5%)
C: No problem level (yield 98.0% or more and less than 99.0%)
D: Acceptable level (yield 96.0% or more and less than 98.0%)
E: Bad level (Yield less than 96.0%)

(2) Evaluation of image performance / high-temperature, high-humidity fogging To 100 parts by mass of toner particles, 3 parts by mass of hydrophobic silica having a specific surface area of 200 m ² / g by the BET method was externally added to obtain a toner. Evaluation was carried out using LBP5800 (manufactured by Canon Inc.) as a one-component developer.

First, 100 g of the obtained toner was filled in a cartridge, and 5000 sheets were endured in an endurance test under a high temperature and high humidity environment (30 ° C./80%). After the endurance test, the average reflectance Dr% of plain paper before image printing was measured by a reflectometer (“REFLECTOMETER MODEL TC-6DS” manufactured by Tokyo Denshoku Co., Ltd.) equipped with a green filter. On the other hand, a solid white image was drawn on plain paper, and then the reflectance Ds% of the solid white image was measured. Fog: Fog% is calculated by the following formula.
Fog (%) = Dr (%) − Ds (%)

(Evaluation criteria)
A: Very good (less than 1.1%)
B: Good (1.1% or more and less than 2.5%)
C: Normal (2.5% or more and less than 4.0%)
D: Poor (4% or more)

(3) Evaluation of thermal characteristics / anti-blocking property About 10 g of toner is put in a 100 ml polycup, left at 50 ° C. for 3 days, and then visually evaluated.

(Evaluation criteria)
A: Aggregates are not seen.
B: Aggregates are slightly seen but easily collapse.
C: Aggregates are seen but easily collapse.
D: Agglomerates are seen, but collapse if shaken.
E: Aggregates can be grasped and do not collapse easily.

[Example 1]
<Dissolution process>
The following materials were heated to 60 ° C. and dissolved and mixed for 30 minutes.
Styrene 70 parts by mass n-butyl acrylate 30 parts by mass Saturated polyester resin (polycondensation product of propylene oxide modified bisphenol A (2 mol adduct) and terephthalic acid (polymerization molar ratio 10:12), Tg = 68 ° C. , Mw = 10000, Mw / Mn = 5.12) 8 parts by mass. HNP-5 (manufactured by Nippon Seiki Co., Ltd.) 8 parts by mass. Carbon black (BET specific surface area = 80 m ² / g, oil absorption = 120 ml / 100 g) 8 parts by mass · E-88 (manufactured by Orient Chemical Industries) 1 part by mass · 0.1 parts by mass of zinc phthalocyanine

<Preparation process of polymerizable monomer composition>
The following materials were mixed in the dissolving liquid obtained in the dissolving step to prepare a polymerizable monomer composition.
-8 parts by mass of polymerization initiator 2,2'-azobis (2,4-dimethylvaleronitrile)

<Granulation process>
After 5 parts by mass of Na ₃ PO ₄ · 12H ₂ O is charged into 332 parts by mass of ion-exchanged water and heated to 60 ° C., it is 58.3 revolutions per second (3500 rpm) using CLEARMIX (M Technique Co., Ltd.). And stirred. To this was added 27 parts by mass of a 1.0 mol / liter-CaCl ₂ aqueous solution to obtain an aqueous medium containing Ca ₃ (PO ₄ ) ₂ .

The polymerizable monomer composition is put into the aqueous medium, and stirred at 75 ° C. (4500 rpm) for 15 minutes with Claremix at 60 ° C. in an N ₂ atmosphere. Granulated.

<Polymerization process>
The granulating liquid of the polymerizable monomer composition was put into a polymerization vessel, and the temperature was raised to 65 ° C. while stirring with a full zone stirring blade (manufactured by Shinko Pantech Co., Ltd.) and allowed to react for 10 hours. After the completion of the polymerization reaction, saturated steam (pure steam / steam pressure 205 kPa / temperature 120 ° C.) was introduced while stirring was continued with a full zone stirring blade. Twenty minutes after the start of the introduction of saturated steam, the temperature of the contents in the container reached 100 ° C., and a distillation fraction began to come out. Residual monomers were distilled off by obtaining a predetermined amount of fractions, and cooled to obtain a toner particle dispersion. The weight average particle diameter of the toner particles was 6.5 μm.

<Washing and solid-liquid separation process>
Hydrochloric acid was added to the obtained toner particle dispersion and stirred to dissolve the Ca ₃ (PO ₄ ) ₂ covering the toner particles, followed by solid-liquid separation with a pressure filter to obtain a toner cake. This was put into water and stirred to obtain a dispersion again, followed by solid-liquid separation with the above-mentioned filter. After redispersion of the toner cake in water and solid-liquid separation were repeated until Ca ₃ (PO ₄ ) ₂ was sufficiently removed, the toner cake was finally obtained by solid-liquid separation.

<Toner storage step 1>
The toner cake obtained in the washing / solid-liquid separation step was sent to the storage device 1 while being pulverized, and was stored until a sufficient amount was sent to the drying step. As the storage device 1, a device as shown in FIG. 1 was used. That is, the flexible partition member which can ventilate the whole inner peripheral surface of the hopper-shaped storage device was installed. A twill-woven cloth (made of polyester, air permeability 12.6 cm ³ / cm ² · sec, manufactured by Kitamura Seisaku Co., Ltd.) was used as the partition member. This twill fabric is made of conductive yarn (Bekarto Tozuna Metal Fiber Co., Ltd.) at 5 mm intervals to make it conductive, and two of these fabrics are inferior angles formed by the diagonal lines of adjacent fabrics as shown in FIG. What was sewed so as to be 90 ° was used as a partition member.

  When the toner cake obtained in the washing / solid-liquid separation process is charged into the toner storage process 1, it is charged from the toner charging port 2 in FIG. It was possible to suppress the generation of dust. Thereafter, after a sufficient amount of the toner cake to be sent to the drying process by repeating the washing and solid-liquid separation process was stored in the storage device 1, the toner discharge port 3 was opened and discharged to the drying process. When discharging the toner cake, compressed air was supplied from the gas supply path 6 and all the gas supply path valves 7 were opened. Thereby, the partition member is deformed by changing the volume of the space formed between the inner wall of the storage device 1 and the partition member, and the toner cake attached to the partition member is effectively removed by ventilating the partition member. It was confirmed that it could be dropped. In addition, it was confirmed that there was no poor discharge such as bridges and ratholes, which are likely to occur with wet powder. When the amount of toner cake in the storage device 1 has decreased, the gas supply path valve 7 opens only the bottom and closes the other to discharge the toner cake in the storage device 1. After the discharge of the toner cake in the storage device 1 was finished, all the gas supply path valves 7 were closed, and the supply of compressed air from the gas supply path 6 was stopped. After the discharge was finished, the yield in the storage device 1 was measured. The results are shown in Table 1.

<Drying process>
The toner cake discharged from the storage device 1 was dried with an air dryer flash jet dryer (manufactured by Seishin Enterprise) to obtain toner particles. The drying conditions were adjusted such that the blowing temperature was 90 ° C., the dryer outlet temperature was 40 ° C., and the supply speed of the toner cake was adjusted so that the outlet temperature did not deviate from 40 ° C. according to the moisture content of the toner cake.

<Toner storage step 2>
The toner particles obtained in the drying process were sent to the storage device 2 and stored until use. The storage device 2 was the same as the toner storage device 1 used in the toner storage step 1.

  When the toner particles obtained in the drying process are charged into the toner storage process 2, they are charged from the toner charging port 2 of FIG. It was possible to suppress the occurrence of Thereafter, when the toner particles in the storage device 2 are used, the toner discharge port 3 is opened and discharged. When discharging the toner particles, compressed air was supplied from the gas supply path 6 and all the gas supply path valves 7 were opened. Thereby, the partition member is deformed by changing the volume of the space formed between the inner wall of the storage device 1 and the partition member, and the toner particles attached to the partition member are effectively removed by ventilating the partition member. It was confirmed that it could be dropped. Further, it was confirmed that the toner particles in the compacted state at the bottom are also promoted to be fluidized by the aeration action, and the discharge failure is suppressed. When the amount of toner particles in the storage device 2 has decreased, the gas supply path valve 7 opens only the bottom and closes the other to discharge the toner particles in the storage device 2. After the discharge of the toner particles in the storage device 2 was finished, all the gas supply path valves 7 were closed, and the supply of compressed air from the gas supply path 6 was stopped. After the discharge was completed, the yield in the storage device 2 was measured. The results are shown in Table 1.

<Evaluation>
The above process was repeated 50 batches, and the yields were measured in the storage device 1 and the storage device 2 after 1 batch production, 20 batch production, and 50 batch production. The obtained toner particles were evaluated according to the above-described image performance evaluation method and thermal property evaluation method. The results are shown in Table 1.

[Example 2]
Toner particles were produced in the same manner as in Example 1 except that the storage device 1 used in the toner storage step 1 and the storage device 2 used in the toner storage step 2 were changed as follows. The evaluation results are shown in Table 1.

The air permeability of the partition member was 0.2 cm ³ / cm ² · sec.

Example 3
Toner particles were produced in the same manner as in Example 1 except that the storage device 1 used in the toner storage step 1 and the storage device 2 used in the toner storage step 2 were changed as follows. The evaluation results are shown in Table 1.

The partition member had an air permeability of 50.0 cm ³ / cm ² · sec.

Example 4
Toner particles were produced in the same manner as in Example 1 except that the storage device 1 used in the toner storage step 1 and the storage device 2 used in the toner storage step 2 were changed as follows. The evaluation results are shown in Table 1.

  A conductive thread was not sewn on the partition member, and a non-conductive partition member was obtained.

Example 5
Toner particles were produced in the same manner as in Example 1 except that the storage device 1 used in the toner storage step 1 and the storage device 2 used in the toner storage step 2 were changed as follows. The evaluation results are shown in Table 1.

  The two twill fabrics used as the partition members were sewn so that the minor angle formed by the oblique line was 30 °.

Example 6
Toner particles were produced in the same manner as in Example 1 except that the storage device 1 used in the toner storage step 1 and the storage device 2 used in the toner storage step 2 were changed as follows. The evaluation results are shown in Table 1.

  Two twill fabrics used as the partition members were sewn so that the minor angle formed by the oblique line was 150 °.

Example 7
Toner particles were produced in the same manner as in Example 1 except that the storage device 1 used in the toner storage step 1 and the storage device 2 used in the toner storage step 2 were changed as follows. The evaluation results are shown in Table 1.

  The two twilled fabrics used as the partition members were sewn so that the minor angle formed by the oblique line was 20 °.

Example 8
Toner particles were produced in the same manner as in Example 1 except that the storage device 1 used in the toner storage step 1 and the storage device 2 used in the toner storage step 2 were changed as follows. The evaluation results are shown in Table 1.

  The two twilled fabrics used as the partition members were sewn so that the minor angle formed by the oblique line was 160 °.

Example 9
Toner particles were produced in the same manner as in Example 1 except that the storage device 1 used in the toner storage step 1 and the storage device 2 used in the toner storage step 2 were changed as follows. The evaluation results are shown in Table 1.

  The twilled cloth used as the partition member was used by sewing one cloth into a cylindrical shape.

[Comparative Example 1]
Toner particles were produced in the same manner as in Example 1 except that the storage device 1 used in the toner storage step 1 and the storage device 2 used in the toner storage step 2 were changed as follows. The evaluation results are shown in Table 1.

  A partition member was not installed in the storage device, and aeration was performed by blowing compressed air directly from the gas supply port. Moreover, as a countermeasure against adhesion to the inner wall of the storage device, an air knocker RKVS15 (manufactured by EXEN) was installed on the outer wall of the storage device. It should be noted that no gas was discharged for dust control when the toner cake and toner particles were put into the storage device.

[Comparative Example 2]
Toner particles were produced in the same manner as in Example 1 except that the storage device 1 used in the toner storage step 1 and the storage device 2 used in the toner storage step 2 were changed as follows. The evaluation results are shown in Table 1.

  A non-breathable conductive rubber sheet NEP-5 (manufactured by Moritec Co., Ltd.) and a thickness of 1 mm were used as a partition member. In addition, since the partition member of the comparative example 2 is a rubber sheet, there is no oblique line.

[Comparative Example 3]
Toner particles were produced in the same manner as in Example 1 except that the storage device 1 used in the toner storage step 1 and the storage device 2 used in the toner storage step 2 were changed as follows. The evaluation results are shown in Table 1.

  As a partitioning member, a Fuji plate (filtration accuracy: 2 μm, manufactured by Fuji Filter Industry Co., Ltd.) that is ventilated but not flexible was used. In addition, the partition member diagonal line direction of the comparative example 3 was not able to be confirmed.

[Comparative Example 4]
Toner particles were produced in the same manner as in Example 1 except that the storage device 1 used in the toner storage step 1 and the storage device 2 used in the toner storage step 2 were changed as follows. The evaluation results are shown in Table 1.

The air permeability of the partition member was 0.1 cm ³ / cm ² · sec.

[Comparative Example 5]
Toner particles were produced in the same manner as in Example 1 except that the storage device 1 used in the toner storage step 1 and the storage device 2 used in the toner storage step 2 were changed as follows. The evaluation results are shown in Table 1.

The air permeability of the partition member was 60.0 cm ³ / cm ² · sec.

  As is clear from Table 1, Examples 1 to 9 of the present invention can obtain a toner with a high yield over a long period of time as compared with Comparative Examples 1 to 5. The toner obtained by the toner production method of the present invention can obtain a toner having stable image quality and thermal characteristics over a long period of time.

  1 toner storage device, 2 toner inlet, 3 toner outlet, 4 partition member, 5 partition member fixture, 6 gas supply path, 7 gas supply path valve, 8 twill cloth, 9 diagonal pattern line, 10 twill line Cloth joint, 11 Inferior angle formed by oblique line of adjacent twill cloth, 12 Superior angle formed by oblique line of adjacent twill cloth

Claims (4)

A storage device for containing toner particles or toner,
The storage device
i) having an air-permeable flexible partition member on the inner periphery of the storage unit;
ii) having gas supply means for supplying gas between the inner wall surface of the storage unit and the partition member;
The partition member is
i) It is deformed by the gas supplied from the gas supply means, and the volume of the space formed between the inner wall surface of the storage device and the partition member is variable,
ii) Breathability is 0.2 cm ³ / cm ² · sec or more and 50.0 cm ³ / cm ² · sec or less,
A storage device characterized by that.   The storage device according to claim 1, wherein the partition member is a conductive cloth.   3. The partition member according to claim 1 or 2, wherein two or more twilled fabrics are joined together, and an inferior angle formed by the oblique lines of the adjacent fabrics is 30 ° or more and 150 ° or less. The storage device described.   A toner production method using the storage device according to claim 1.

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