JP5504787B2 - Toner product for developing electrostatic latent image and image forming method - Google Patents

Description

  The present invention relates to an electrostatic latent image developing toner product and an image forming method using the same.

  2. Description of the Related Art In recent years, when an image is formed by an electrophotographic image forming method, energy saving performance of a multifunction machine or a printer has been demanded. Therefore, development of a technique for lowering a toner fixing temperature is important. As such a technique, a technique in which a crystalline polyester resin and an amorphous polyester resin are used in combination as a toner binder resin to achieve both low-temperature fixability and storage stability of the toner is known (for example, Patent Documents). 1).

  In general, a toner container for containing toner is made of a polyolefin resin such as polyethylene having a relatively small polarity. However, when a toner made of a highly polar resin such as a polyester resin is accommodated in such a toner container, the amount of toner adhering to the inner wall surface of the toner container increases due to charging caused by friction between the toner container and the toner inside. . As a result, when the toner in the toner container is supplied to the image forming apparatus, there is a problem that the amount of toner remaining in the toner container increases.

  In order to solve such a problem, a method of suppressing frictional charging between the toner container and the toner in the toner container by incorporating an antistatic agent into the resin constituting the toner container has been proposed (for example, Patent Document 2). However, since the antistatic agent generally has a large amount of moisture adsorption, the amount of moisture adsorption to the toner container increases especially in a high temperature and high humidity environment, and the toner contained in the toner container also has a large amount of moisture adsorption. . As a result, there is a problem that defects such as fogging occur in the obtained image.

JP 2007-4033 A JP-A-6-67536

  The present invention has been made based on the circumstances as described above, and the purpose thereof is that frictional charging between the electrostatic latent image developing toner container and the toner in the container does not occur so much. Toner product and image for electrostatic latent image development that can reduce the amount of toner remaining in the container at the time of toner supply and can form a high-quality image that does not cause image defects even in a high-temperature and high-humidity environment It is to provide a forming method.

  The object of the present invention is achieved by adopting the following configuration.

(1)
A toner product in which a toner is contained in a toner container, the toner comprising toner particles containing at least a polyester resin synthesized from an aliphatic dicarboxylic acid and an aliphatic diol, and the toner container includes at least 3-hydroxybutyric acid An electrostatic latent image developing toner product comprising a resin containing a copolymerized polyester of 2-hydroxyhexanoic acid.

(2)
The polyester resin comprising an aliphatic dicarboxylic acid and an aliphatic diol contained in the toner has a ratio of carbon atoms (C) to carbonyl oxygen atoms (O) of 7: 1 to 10: 1 (1). The toner product for developing an electrostatic latent image according to (1).

(3)
(1) or (2), wherein the resin constituting the toner container has a content of a copolymerized polyester of 3-hydroxybutyric acid and 3-hydroxyhexanoic acid of 10 to 100% by mass. Toner products for developing electrostatic latent images.

(4)
An image forming method comprising using the toner product for developing an electrostatic latent image according to any one of (1) to (3).

  According to the present invention, the electrostatic charging of the electrostatic latent image developing toner container and the toner in the container does not cause much frictional charging. As a result, the toner remaining amount in the container can be reduced when the toner is supplied, It is possible to provide an electrostatic latent image developing toner product and an image forming method capable of forming a high-quality image free from image defects even in a wet environment.

Schematic which shows an example of the toner container used for the toner product of this invention.

  Hereinafter, the present invention will be specifically described.

  According to the toner product of the present invention, the toner is composed of toner particles composed of a binder resin including a polyester resin composed of at least an aliphatic dicarboxylic acid and an aliphatic diol, and the toner container is composed of at least 3-hydroxybutyric acid and 3-hydroxy It consists of a resin containing hexanoic acid copolyester. By using a toner made of a polyester resin having a specific carbonyl oxygen ratio, frictional charging with the toner container is suppressed. As a result, the amount of toner that adheres electrostatically to the inner wall surface of the toner container is reduced, so that the amount of toner remaining in the toner container when toner is supplied can be reduced. Further, even in a high-temperature and high-humidity environment, a toner container made of a resin containing a copolymerized polyester of 3-hydroxybutyric acid and 3-hydroxyhexanoic acid has a small amount of moisture adsorption to the container body, and the toner has a certain amount of polarity In the case of having a group, since the amount of moisture adsorbed on the toner is small, the charging characteristics are not affected, so that a high-quality image free from image defects such as fogging can be formed.

  The reason why the frictional charging between the toner container and the toner in the toner container is suppressed is that the polyester resin has a specific carbonyl oxygen ratio to control the negative chargeability and is contained in the resin constituting the toner container. By limiting the ratio of the carbonyl oxygen ratio resulting from the copolymerized polyester of hydroxybutyric acid and 3-hydroxyhexanoic acid, the toner container is configured with polar groups present on the surface of the toner particles constituting the toner in the toner container. This is presumed to be due to electrostatic repulsion between the polar groups of the resin to be treated.

  Further, according to the toner product of the present invention, since the resin constituting the toner container contains a copolymerized polyester of 3-hydroxybutyric acid and 3-hydroxyhexanoic acid, 3-hydroxybutyric acid and 3-hydroxyhexane are obtained. Due to the biodegradable properties of the acid copolyester, the burden on the environment can be basically reduced.

[Toner products]
The toner product of the present invention comprises toner particles composed of a binder resin containing at least a polyester resin composed of an aliphatic dicarboxylic acid and an aliphatic diol, and the toner container is a copolymer of at least 3-hydroxybutyric acid and 3-hydroxyhexanoic acid. It consists of resin containing polyester.

[Toner container]
The toner container constituting the toner product of the present invention comprises at least a copolymerized polyester of 3-hydroxybutyric acid and 3-hydroxyhexanoic acid.

  The copolymerized polyester of 3-hydroxybutyric acid and 3-hydroxyhexanoic acid contained in the resin constituting the toner container can be prepared by various methods, but must be synthesized by microorganisms from the viewpoint of environmental considerations. Is preferred. Specifically, it accumulates in the body of bacteria by growing specific bacteria using sugar or natural oil as a carbon source.

  The composition ratio in the copolymerized polyester of 3-hydroxybutyric acid and 3-hydroxyhexanoic acid is 50-98 mol% 3-hydroxybutyric acid, 50-2 mol% 3-hydroxyhexanoic acid, more preferably 75-95 mol% 3-hydroxybutyric acid, It is preferable that it is 25-5 mol% of 3-hydroxyhexanoic acid. If the proportion of 3-hydroxybutyric acid exceeds 98%, the mechanical properties of the copolymer are lowered, and the mechanical strength is low when a toner container is produced. When the proportion of 3-hydroxybutyric acid is less than 50 mol%, the productivity of the copolymer is remarkably lowered and the feasibility is lowered.

  The resin constituting the toner container is a resin composed only of a copolymerized polyester of 3-hydroxybutyric acid and 3-hydroxyhexanoic acid, or a mixture of a copolymerized polyester of 3-hydroxybutyric acid and 3-hydroxyhexanoic acid and another resin material. It consists of the resin formed.

  Examples of the resin material used in combination with the copolymerized polyester of 3-hydroxybutyric acid and 3-hydroxyhexanoic acid include 3-hydroxybutyric acid homopolymer, polycarbonate resin, and polyolefin resin. Moreover, a flame retardant, antioxidant, etc. can be contained as needed.

  Although it does not specifically limit as a polycarbonate-type resin, For example, an aliphatic polycarbonate, an aromatic polycarbonate, etc. are mentioned. Specific examples of the polyolefin resin include very low density polyethylene (VLDPE), linear low density polyethylene (LLDPE), low density polyethylene (LDPE), medium density polyethylene (MDPE), high density polyethylene (HDPE), Examples include polypropylene (PP), ethylene / propylene rubber (EPM), ethylene / vinyl acetate copolymer (EVA), and ethylene / acrylic acid ester copolymer (EEA).

  The resin constituting the toner container preferably has a content of the copolymerized polyester of 3-hydroxybutyric acid and 3-hydroxyhexanoic acid of 10 to 100% by mass, more preferably 25 to 100% by mass. is there.

  When the content ratio of the copolymerized polyester of 3-hydroxybutyric acid and 3-hydroxyhexanoic acid is less than 10% by mass, frictional charging between the toner container and the toner in the toner container may not be sufficiently suppressed. .

  As the copolyester of 3-hydroxybutyric acid and 3-hydroxyhexanoic acid contained in the resin constituting the toner container, it is preferable to use a polyester having a weight average molecular weight of 50,000 to 3,000,000, more preferably 100,000 to 2 million. When the weight average molecular weight is less than 50,000, the melt viscosity becomes low, and it may be difficult to form the film thickness uniformly. On the other hand, in the case where the weight average molecular weight exceeds 3 million, the melt viscosity becomes too high and it may be difficult to mold as a container.

  A weight average molecular weight shall be measured from the polystyrene conversion molecular weight distribution using the gel permeation chromatography (GPC) which used chloroform eluent.

  The thickness of the toner container is preferably 0.5 to 5.0 mm, more preferably 0.5 to 3.0 mm.

  When the thickness of the toner container is larger than 5.0 mm, the resin is used more than securing the strength, resulting in an increase in cost. On the other hand, when the thickness of the toner container is smaller than 0.5 mm, the required strength may not be ensured.

  The shape of the toner container is not particularly limited, and for example, a shape as shown in FIG.

  In FIG. 1, this toner container has a spiral groove 403 on the outer surface of a bottle-shaped toner container body 402 and at least one linear groove 404 in the longitudinal direction of the toner container body 402. When a container guide member 405 having an engaging projection 407 that engages with the linear groove 404 is provided on the inner periphery, the linear groove 404 and the engaging projection 407 are engaged. In addition, the toner container is detachably attached to the image forming apparatus, and the container guide member 405 can be rotated together with the toner container main body 402 when attached.

  Examples of the method for producing the toner container of the present invention include a blow molding method, an injection molding method, and an extrusion molding method. In particular, it is preferably produced by a blow molding method.

[Toner composition and production method]
The toner used in the toner product of the present invention is composed of toner particles composed of a binder resin containing at least a polyester resin composed of an aliphatic dicarboxylic acid and an aliphatic diol (hereinafter also referred to as an aliphatic polyester resin). is there.

(Binder resin)
In addition to the aliphatic polyester resin, other resins may be used in combination as the toner binder resin. For example, a polyester resin containing either an aromatic polyvalent carboxylic acid or an aromatic polyhydric alcohol (hereinafter referred to as an aromatic resin). And a styrene-acrylic resin, a styrene resin, an acrylic resin, and the like. In these, it is preferable to use together the polyester resin and styrene acrylic resin containing an aromatic.

  The binder resin of the toner preferably has an aliphatic polyester resin content of 50 to 80% by mass.

  As an aliphatic dicarboxylic acid, for example, oxalic acid. Succinic acid, glutaric acid, adipic acid, peric acid, azelaic acid, sebacic acid, 1,9-nonanedicarboxylic acid, 1,10-decanedicarboxylic acid, 1,12-dodecanedicarboxylic acid, 1,14-tetradecanedicarboxylic acid, Examples include 1,18-octadecanedicarboxylic acid.

  On the other hand, the aliphatic diol is preferably a linear aliphatic diol having 2 to 20 carbon atoms in the main chain portion. The branched aliphatic diol lowers the melting point of the resulting polyester resin, so that the straight-chain type is preferred from the viewpoints of toner blocking properties and image storage stability. Examples of the linear aliphatic diol include ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1, 8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, 1,13-tridecanediol, 1,14-tetradecanediol, 1, Although 18-octadecanediol etc. are mentioned, it is not limited to these.

  In the polyester resin comprising an aliphatic carboxylic acid and an aliphatic diol, the ratio of carbon atom (C) to carbonyl oxygen atom (O) is preferably 7: 1 to 10: 1. By setting the above range, thermal properties excellent in low-temperature fixability and storage stability can be obtained as a binder resin, and between a toner container made of a copolymerized polyester of 3-hydroxybutyric acid and 3-hydroxyhexanoic acid. A sufficient electrostatic repulsive force can be maintained, and the amount of toner adhering to the toner container can be reduced.

  Examples of the aromatic polyvalent carboxylic acid include terephthalic acid, isophthalic acid, phthalic anhydride, trimellitic anhydride, pyromellitic acid, naphthalenedicarboxylic acid, and the like.

  Examples of the aromatic polyhydric alcohol include bisphenol A alkylene oxide adducts such as bisphenol A propylene oxide adduct and bisphenol A ethylene oxide adduct.

  The aromatic polyester-containing polyester resin may contain any other polyvalent carboxylic acid or polyhydric alcohol as long as it contains either an aromatic polyvalent carboxylic acid or an aromatic polyhydric alcohol. Examples of the polyvalent carboxylic acid include maleic anhydride, fumaric acid, succinic acid, alkenyl succinic acid, adipic acid, peric acid, azelaic acid, sebacic acid, 1,9-nonanedicarboxylic acid, and 1,10-decanedicarboxylic acid. 1,12-dodecanedicarboxylic acid, 1,14-tetradecanedicarboxylic acid, aliphatic carboxylic acids such as 1,18-octadecanedicarboxylic acid; cycloaliphatic carboxylic acids such as cyclohexanedicarboxylic acid; and lower alkyl esters of these acids , Acid anhydrides, and the like, and one or more of these can be used. Examples of the polyhydric alcohol include ethylene glycol, propylene glycol, 1,4-butanediol, 2,3-butanediol, diethylene glycol, triethylene glycol, 1,5-pentanediol, 1,6-hexanediol, and neopenty. Examples include reglycol, 1,4-cyclohexanedimethanol, dipropylene glycol, polyethylene glycol, polypropylene glycol, glycerin, sorbitol, 1,4-sorbitan, and trimethylolpropane.

  Examples of the method for producing the toner used in the toner product of the present invention include a kneading / pulverizing method, an emulsion aggregation method, an encapsulation method, and other known methods. Among these, it is preferable to use a kneading / pulverizing method or an emulsion aggregation method.

  The kneading and pulverization method includes a step of mixing raw materials such as a binder resin, a colorant and a release agent with a mechanical mixer, a step of melt-kneading the mixture with a twin screw extruder, and the like. After cooling, the toner particles are produced by a step of coarsely pulverizing, a step of finely pulverizing the coarsely pulverized particles, and a step of classifying the finely pulverized particles.

  In the emulsion aggregation method, a dispersion in which resin particles are dispersed in a surfactant aqueous solution by a phase inversion emulsification method or a mechanical emulsification method is used as a component of toner particles such as other colorant fine particles. The mixture is mixed with a dispersion liquid of the mixture, slowly agglomerated while balancing the repulsive force on the surface of the fine particles by adjusting the pH and the aggregating force by adding an aggregating agent made of an electrolyte, and the association is performed while controlling the particle size and particle size distribution At the same time, it is a method for producing toner particles by controlling the shape by fusing fine particles by heating and stirring.

(Coloring agent)
As the colorant constituting the toner, known inorganic or organic colorants can be used.

  The addition amount of the colorant is in the range of 1 to 30% by mass, preferably 2 to 20% by mass with respect to the whole toner.

(Offset prevention agent)
The toner may contain an offset preventing agent for suppressing the offset phenomenon. Here, the offset inhibitor is not particularly limited, and for example, polyethylene wax, oxidized polyethylene wax, polypropylene wax, oxidized polypropylene wax, carnauba wax, fatty acid ester wax, sazol wax, rice wax, Candelilla wax, jojoba oil wax, beeswax wax and the like can be mentioned.

  The content of the anti-offset agent in the toner particles is usually 1 to 30 parts by mass, and more preferably 5 to 20 parts by mass with respect to 100 parts by mass of the binder resin for toner particle formation.

(Charge control agent)
The toner may contain a charge control agent. Examples thereof include metal complexes (salicylic acid metal complexes) of salicylic acid derivatives such as zinc and aluminum, calixarene compounds, organic boron compounds, and fluorine-containing quaternary ammonium salt compounds.

  The content ratio of the charge control agent in the toner particles is usually 0.1 to 5.0 parts by mass with respect to 100 parts by mass of the binder resin.

(Particle size of toner particles)
The particle diameter of the toner particles is preferably, for example, 3.0 to 10 μm, more preferably 4.0 to 8.0 μm in terms of volume-based median diameter. The volume-based median diameter can be controlled by adjusting the conditions of the fine pulverization step and the classification step when the toner production method is, for example, a kneading / pulverization method. On the other hand, in the case of the emulsion aggregation method, it can be controlled by the concentration of the coagulant (salting-out agent) to be used, the addition amount of the organic solvent, the fusion time, and the composition of the polymer.

  When the volume-based median diameter is in the above range, the transfer efficiency is increased, the image quality of halftone is improved, and the image quality of fine lines and dots is improved.

The volume-based median diameter (D ₅₀ ) of the toner particles can be measured and calculated using an apparatus in which a computer system for data processing is connected to “Multisizer 3 (manufactured by Beckman Coulter)”.

  Specifically, 0.02 g of toner was conditioned with 20 ml of a surfactant solution (for example, a surfactant solution obtained by diluting a neutral detergent containing a surfactant component 10 times with pure water for the purpose of dispersing the toner). Thereafter, ultrasonic dispersion is performed for 1 minute to prepare a toner dispersion. This toner dispersion is injected into a beaker containing “ISOTONII (manufactured by Beckman Coulter)” in a sample stand with a pipette until the measured concentration reaches 5 to 10%, and the measurement is set to 25000 counts. To do. The aperture diameter of “Multisizer 3” is 50 μm.

(External additive)
In order to improve fluidity, chargeability, cleaning properties, etc., the toner can be constituted by adding external additives such as a fluidizing agent and a cleaning aid to the toner particles.

  Examples of the external additive include inorganic oxide fine particles composed of silica fine particles, alumina fine particles, titanium oxide fine particles, inorganic stearate compound fine particles such as aluminum stearate fine particles and zinc stearate fine particles, strontium titanate, titanium, and the like. Inorganic titanic acid compound fine particles such as zinc acid are listed. These can be used individually by 1 type or in combination of 2 or more types.

  These inorganic fine particles are preferably subjected to surface treatment with a silane coupling agent, a titanium coupling agent, a higher fatty acid, silicone oil or the like in order to improve heat-resistant storage stability and environmental stability.

  The total amount of these various external additives added is 0.1 to 10 parts by mass with respect to 100 parts by mass of the toner. In addition, various external additives may be used in combination.

(Developer)
The toner used in the toner product of the present invention can be used as a magnetic or non-magnetic one-component developer, but may be used as a two-component developer by mixing with a carrier. When this toner is used as a two-component developer, the carrier is a magnetic particle made of a conventionally known material such as a metal such as iron, ferrite, or magnetite, or an alloy of such a metal with a metal such as aluminum or lead. In particular, ferrite particles are preferable. Further, as the carrier, a coat carrier in which the surface of the magnetic particles is coated with a coating agent such as a resin, a binder type carrier in which a magnetic fine powder is dispersed in a binder resin, or the like may be used.

  The coating resin constituting the coat carrier is not particularly limited, and examples thereof include olefin resins, styrene resins, styrene-acrylic resins, acrylic resins, silicone resins, ester resins, and fluorine resins. Moreover, it does not specifically limit as binder resin which comprises a binder type carrier, A well-known thing can be used, For example, a styrene-acrylic resin, a polyester resin, a fluororesin, a phenol resin etc. can be used. Among these, a coat carrier coated with a styrene-acrylic resin or an acrylic resin is preferable from the viewpoint of chargeability and durability.

  The carrier preferably has a volume average particle size of 20 to 100 μm, more preferably 25 to 80 μm, since a high-quality image can be obtained and carrier fog is suppressed. The volume average particle diameter of the carrier can be typically measured by a laser diffraction particle size distribution measuring apparatus “HELOS (manufactured by SYMPATEC)” equipped with a wet disperser.

  According to the above toner product, the toner comprises toner particles composed of a binder resin including at least a polyester resin composed of an aliphatic dicarboxylic acid and an aliphatic diol, and the toner container includes at least 3-hydroxybutyric acid and 3 -Since it is made of a copolymerized polyester of hydroxyhexanoic acid, frictional charging between the toner container and the toner in the toner container is suppressed, so that the toner that inevitably electrostatically adheres to the inner wall surface of the toner container. Since the amount decreases, the amount of toner remaining in the toner container when supplying the toner can be reduced, and the toner has an appropriate amount of polar groups even in a high temperature and high humidity environment. Therefore, it is possible to form a high-quality image free from image defects such as fogging.

  Furthermore, since the resin constituting the toner container contains a copolymerized polyester of 3-hydroxybutyric acid and 3-hydroxyhexanoic acid, biodegradation characteristics of the copolymerized polyester of 3-hydroxybutyric acid and 3-hydroxyhexanoic acid are obtained. Thus, the load on the environment can be basically reduced.

  Hereinafter, specific examples of the present invention will be described, but the present invention is not limited thereto.

<< Production of Aliphatic Polyester Resin >>
<Preparation of Aliphatic Polyester Resin A1>
Into a three-necked flask, 10 mol% of 1,6-hexanediol and 10 mol% of sebacic acid and 0.014% by mass of titanium tetra-n-butoxide as a catalyst with respect to the carboxylic acid component were added. The pressure is reduced. Further, the atmosphere was replaced with nitrogen gas under an inert atmosphere, and the mixture was refluxed at 180 ° C. for 6 hours by a stirring operation. Thereafter, the unreacted monomer component was removed by distillation under reduced pressure, the temperature was gradually raised to 220 ° C., and the mixture was stirred for 12 hours to prepare a polyester resin A1.

  When the molecular weight of the obtained polyester resin A1 was confirmed by GPC, the weight average molecular weight in terms of styrene was 16,000. Further, when the thermal characteristics were measured at a heating rate of 10 ° C./min with a differential scanning calorimeter, the melting point was 63 ° C.

<Preparation of Aliphatic Polyester Resin A2 to A8>
Polyester resins A2 to A8 were produced in the same manner as in the production of the polyester resin A1, except that the aliphatic dicarboxylic acid component and the aliphatic diol component were changed to the materials shown in Table 1.

<< Preparation of Aliphatic Polyester Resin Dispersion >>
<Preparation of Aliphatic Polyester Resin A1 Dispersion>
The following materials were heated to 100 ° C. and sufficiently dispersed with IKA Ultra Tarrax T50, followed by dispersion treatment with a Gorin homogenizer for 1 hour, a polyester resin A1 having a volume average particle size of 200 nm and a solid content of 30%. A dispersion was obtained.

Polyester resin A1: 90 parts by mass Anionic surfactant Neogen RK: 1.5 parts by mass Ion exchange water: 208.5 parts by mass << Preparation of polyester resin containing aromatics >>
<Production of Aromatic Polyester Resin B1>
Into a reaction vessel equipped with a stirrer, temperature sensor, cooling pipe, and nitrogen introduction device, the polyvalent carboxylic acid component and polyhydric alcohol component shown below are charged, and the reaction vessel is replaced with dry nitrogen gas, and then used as a catalyst. Titanium tetra-n-butoxide 0.05 mol% was added, and the mixture was stirred at 195 ° C. for 6 hours under a nitrogen gas stream. The temperature was further raised to 240 ° C. and the mixture was stirred for 6.0 hours. The pressure was reduced to 0.0 mmHg (1 mmHg was 133.322 Pa), and the reaction was stirred for 0.5 hours under reduced pressure to prepare polyester resin B1.

(Polyvalent carboxylic acid component)
Terephthalic acid: 40 mol%
Fumaric acid: 20 mol%
Dodecenyl succinic anhydride: 35 mol%
Trimellitic anhydride: 5 mol%
(Polyhydric alcohol component)
Bisphenol A ethylene oxide 2-mol adduct: 10 mol%
Bisphenol A propylene oxide 2 mol adduct: 90 mol%
<Preparation of Polyester Resin B2 Containing Aromatics>
A polyester resin B2 was produced in the same manner as in the production of the polyester resin B1, except that the polyvalent carboxylic acid component and the polyhydric alcohol component were changed as follows.

(Polyvalent carboxylic acid component)
Terephthalic acid: 70 mol%
Fumaric acid: 10 mol%
Dodecenyl succinic anhydride: 20 mol%
(Polyhydric alcohol component)
Bisphenol A ethylene oxide 2-mol adduct: 10 mol%
Bisphenol A propylene oxide 2 mol adduct: 90 mol%
<Preparation of styrene-acrylic resin C dispersion>
(1) First-stage polymerization A reaction vessel equipped with a stirrer, a temperature sensor, a cooling tube, and a nitrogen introducing device was charged with a solution prepared by dissolving 8 parts by mass of sodium dodecyl sulfate in 3000 parts by mass of ion-exchanged water, and under a nitrogen stream The internal temperature was raised to 80 ° C. while stirring at a stirring speed of 230 rpm. After the temperature increase, a solution in which 10 parts by mass of potassium persulfate was dissolved in 200 parts by mass of ion-exchanged water was added, the liquid temperature was again adjusted to 80 ° C., and the following monomer mixture was added dropwise over 1 hour, followed by After heating for 2 hours, polymerization was carried out by stirring to prepare resin particles [1H].

Styrene 480 parts by mass n-butyl acrylate 250 parts by mass Methacrylic acid 68 parts by mass n-octyl-3-mercaptopropionate 16 parts by mass (2) Second-stage polymerization Agitator, temperature sensor, condenser, and nitrogen inlet are attached. Into the reaction vessel, a solution prepared by dissolving 7 parts by mass of sodium polyoxyethylene (2) dodecyl ether sulfate in 800 parts by mass of ion-exchange water was heated to 98 ° C., and then 260 parts by mass of the resin particles [1H] A solution prepared by dissolving the following monomer solution at 90 ° C. is added, and mixed and dispersed for 1 hour by a mechanical disperser “CLEARMIX (manufactured by M Technique Co., Ltd.)” having a circulation path, including emulsified particles (oil droplets). A dispersion was prepared.

Styrene 245 parts by mass n-butyl acrylate 120 parts by mass n-octyl-3-mercaptopropionate 1.5 parts by mass Pentaerythritol tetrabehenate 190 parts by mass Next, 6 parts by mass of potassium persulfate is ionized in this dispersion. An initiator solution dissolved in 200 parts by mass of exchange water was added, and this system was polymerized by heating and stirring at 82 ° C. for 1 hour to obtain resin particles [1HM].

(3) Third-stage polymerization Further, a solution in which 11 parts by mass of potassium persulfate was dissolved in 400 parts by mass of ion-exchanged water was added, and under a temperature condition of 82 ° C,
Styrene 456 parts by weight n-butyl acrylate 135 parts by weight Methacrylic acid 9 parts by weight n-octyl-3-mercaptopropionate A monomer mixture consisting of 8 parts by weight was added dropwise over 1 hour. After completion of the dropping, the mixture was heated and stirred for 2 hours, and then cooled to 28 ° C. to obtain a styrene-acrylic resin C dispersion.

<Preparation of Colorant Dispersion D>
90 parts by mass of sodium dodecyl sulfate was dissolved in 1600 parts by mass of ion-exchanged water with stirring. While stirring this solution, 420 parts by mass of carbon black “Regal 330R (manufactured by Cabot)” as a colorant is gradually added, and then dispersed using a stirring device “CLEARMIX (manufactured by M Technique)”. Thus, a dispersion of colorant particles (hereinafter referred to as “colorant dispersion D”) was prepared. The particle diameter of the colorant particles in this colorant dispersion D was measured using an electrophoretic light scattering photometer “ELS-800 (manufactured by Otsuka Electronics Co., Ltd.)” and found to be 110 nm.

<Production of toner>
<Preparation of Toner 1>
(Toner material)
Polyester resin A1: 60 parts by weight Polyester resin B1: 20 parts by weight Polyester resin B2: 20 parts by weight Carbon black “Mogal L” (manufactured by Cabot Corporation): 8 parts by weight Polyethylene wax (melting point: 97 ° C.): 5 parts by weight After thoroughly mixing the toner material with a “Henschel mixer” (Mitsui Mining Co., Ltd.), the mixture is melt-kneaded with a twin screw extrusion kneader “PCM” (Ikegai Co., Ltd.), cooled rapidly, and then a “feather mill”. Coarsely pulverized with (Hosokawa Micron). Next, this coarsely pulverized product is pulverized by a jet pulverizer “IDS” (manufactured by Nippon Pneumatic Kogyo Co., Ltd.), classified by a mechanical classifier “turboplex ATP” (manufactured by Hosokawa Micron), and the median diameter on a volume basis. Produced toner base particles 1 having a particle size of 6.4 μm.

  1% by mass of hydrophobic silica (number average primary particle size = 12 nm) and 0.5% by mass of hydrophobic titania (number average primary particle size = 20 nm) are added to the toner base particles 1 and mixed with a Henschel mixer. Thus, Toner 1 was produced.

<Preparation of Toner 2 to 11 and Toner 13>
Toners 2 to 11 and Toner 13 were prepared in the same manner as that of Toner 1 except that the binder resin was changed to the binder resin and composition ratio shown in Table 2.

<Preparation of Toner 12>
The following materials were placed in cylindrical stainless steel and dispersed and mixed for 30 minutes while applying a shearing force at 800 rpm with an ultra turrax.

Polyester resin A1 dispersion: 80 parts by mass (solid content conversion)
Styrene-acrylic resin C dispersion: 20 parts by mass (in terms of solid content)
Colorant dispersion D: 8 parts by mass (in terms of solid content)
Nonionic surfactant: 0.5 part by mass Next, 0.1 part by mass of a 10% nitric acid aqueous solution of polyaluminum chloride was added dropwise to the obtained dispersion as a flocculant. At this time, the pH of the dispersion was adjusted to 4.2 using 0.4 mol / liter nitric acid or 1 mol / liter sodium hydroxide aqueous solution as necessary. Thereafter, the dispersion was transferred to a polymerization kettle equipped with a stirrer and a thermometer and heated to promote the growth of aggregated particles at 40 ° C., and the volume-based median diameter was set to 6.0 μm.

  Next, the pH was adjusted to 9.0, the temperature was raised to 95 ° C. and held for 6 hours, and then the pH was gradually lowered to stop heating and allow to cool.

  The produced particles were filtered and washed, and then dried until the water content became 0.5% by mass to prepare toner base particles 12 having a volume-based median diameter of 6.2 μm.

  1% by mass of hydrophobic silica (number average primary particle size = 12 nm) and 0.5% by mass of hydrophobic titania (number average primary particle size = 20 nm) are added to the toner base particles 12 and mixed with a Henschel mixer. Thus, toner 12 was produced.

(Development of developer)
100 parts by mass of ferrite core particles and 5 parts by mass of copolymer resin particles of cyclohexyl methacrylate / methyl methacrylate (copolymerization ratio 5/5) are put into a high-speed mixer equipped with stirring blades, and stirred and mixed at 120 ° C. for 30 minutes. A resin coat layer was formed on the surface of the ferrite core particles by the action of a mechanical impact force to obtain a ferrite carrier having a volume-based median diameter of 40 μm.

  A ferrite carrier prepared as described above was mixed with toners 1 to 13 using a V-type mixer so that the toner concentration was 6% by mass to prepare a developer.

[Toner Container Preparation Examples 1 to 10]
According to the resin composition and composition ratio shown in Table 3, toner containers [1] to [10] shown in FIG. The thickness of the toner containers [1] to [10] was 2.5 mm.

[Examples 1-19, Comparative Examples 1-3]
Using the toner products obtained by combining the toners 1 to 13 obtained as described above and the toner containers [1] to [10] as shown in Table 4, the following evaluations (1) to (3) were performed. went.

(1) Residual amount of toner A toner container filled with 400 g of toner is attached to a single drive device, and a measuring device is installed under an open toner supply port in an environment of 20 ° C. and 50% RH. The mass A (g) when the change of the value disappeared was measured. Here, the single drive device can forcibly discharge the toner from the toner supply port by rotating the toner conveying screw of the toner container from the outside. The remaining toner amount B (%) is expressed by the following formula (3). The smaller the value, the smaller the amount of toner remaining in the toner container. The

Formula (3): B (%) = (400−A) / 400 × 100
(2) Fog A toner product in which a toner container is filled as shown in Table 4 has a printing rate of 3% on A4 size fine paper (64 g / m ² ) in an environment of 30 ° C. and 80% RH. An image was formed on 100,000 low-pixel images (character images) in the single-sheet intermittent mode, and a solid white image was output after the completion of the 100,000 sheets. Here, “bizhub 920 (manufactured by Konica Minolta Business Technologies)” was used as the image forming apparatus.

  The fog density is determined by measuring the absolute image density at 12 locations using a reflection densitometer (“RD-918 (manufactured by Macbeth Co.)”) and calculating the average value for the blank paper that has not been printed. Next, for the solid white image output after the completion of 100,000 sheets, the absolute image density at 12 locations was similarly measured to obtain an average value, and the value obtained by subtracting the blank paper density from this average value was used as the fog density. As evaluated. If the fog density is less than 0.010, there is no practical problem.

(3) Drop test For toner containers [1] to [10] filled with 400 g of toner, hold both ends of the toner container by hand and drop 20 times from a point of 1 m in height. Or damage, dents, etc.) or toner leakage was visually confirmed. If there is no abnormality at the end of 10 times, there is no practical problem.

  As described above, according to Examples 1 to 19 of the present invention, it is possible to reduce the remaining amount of toner and to reliably form a high-quality image that does not cause fogging even in a high-temperature and high-humidity environment. Confirmed that you can.

402 toner container body 403 spiral groove 404 linear groove 405 container guide member 407 engagement protrusion

Claims (4)

  A toner product in which a toner is contained in a toner container, the toner comprising toner particles containing at least a polyester resin synthesized from an aliphatic dicarboxylic acid and an aliphatic diol, and the toner container includes at least 3-hydroxybutyric acid An electrostatic latent image developing toner product comprising a resin containing a copolymerized polyester of 2-hydroxyhexanoic acid.   The polyester resin comprising an aliphatic dicarboxylic acid and an aliphatic diol contained in the toner has a ratio of carbon atoms (C) to carbonyl oxygen atoms (O) of 7: 1 to 10: 1. 1. The toner product for developing an electrostatic latent image according to 1.   3. The static resin according to claim 1, wherein the resin constituting the toner container has a content of a copolymerized polyester of 3-hydroxybutyric acid and 3-hydroxyhexanoic acid of 10 to 100% by mass. Toner product for developing electrostatic latent images.   An image forming method using the toner product for developing an electrostatic latent image according to claim 1.

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