JP2014006371A - Toner and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide toner which can be sufficiently plastically deformed even with low pressure, when pressure and fixation are performed under non-heating or low temperature condition and is excellent in fixability and to provide an image forming apparatus using the toner.SOLUTION: Toner contains a cyclic olefin resin 4, a wax 5, a hard particle 6, the compound amount of the wax 5 is 15 wt.% to 30 wt.% with respect to the total amount of the toner 3, and the compound amount of the hard particle 6 is 15 wt.% to 30 wt.% with respect to the total amount of the toner 3.

Description

  The present invention relates to a toner used in an electrophotographic image forming apparatus such as a copying machine, a printer, and a facsimile machine, a fixing device, and an image forming apparatus including the fixing device.

  An electrophotographic image forming apparatus (for example, a printer) includes a fixing device that fixes a toner image formed on a recording member (recording paper or paper) onto the paper by heat melting. As an example of this fixing device, as disclosed in Patent Document 1, a roller-pair type fixing device including a fixing roller and a pressure roller is known.

  The fixing roller is a roller member in which an elastic layer is formed on the surface of a hollow metal core made of metal such as aluminum, and a halogen lamp is arranged as a heat source inside the core metal. Then, the temperature control device controls the temperature of the fixing roller surface by controlling the halogen lamp on / off based on a signal output from a temperature sensor provided on the surface of the fixing roller.

  The pressure roller is a roller member in which a heat-resistant elastic layer such as silicon rubber is provided as a coating layer on a cored bar. The pressure roller is pressed against the peripheral surface of the fixing roller, and a nip region is formed between the fixing roller and the pressure roller by elastic deformation of the elastic layer of the pressure roller.

  In the above configuration, the fixing device sandwiches the paper on which the unfixed toner image is formed in the nip region between the fixing roller and the pressure roller, and conveys the paper by rotating both the rollers, The toner image on the sheet is melted and fixed on the sheet by the heat of the peripheral surface of the fixing roller.

  However, in the conventional roller pair system, immediately after the power is turned on in the morning, the fixing roller and the pressure roller are at room temperature. Further, in the atmospheric state where the copying operation is not performed, the roller surface needs to be maintained at a predetermined temperature. Therefore, the heating must always be performed even when the copying operation is not performed. In addition to these copying operations, useless energy is consumed.

In order to solve such a problem, it is disclosed that low-temperature fixing is achieved by using a cyclic olefin resin in a toner and converting it into a capsule (Patent Document 2).
In this belt fixing device, since the fixing belt having a small heat capacity is heated, the warm-up time is short, and it is not necessary to incorporate a heat source such as a halogen lamp in the fixing roller. It is possible to provide a wide nip width.

Japanese Patent Laid-Open No. 11-38802 JP 2000-147829 A

  However, the encapsulation leads to an increase in cost, and there is a limit to the low-temperature fixing even if a resin having a low glass transition point (low Tg) is used as a core and a resin having a high Tg is used as a shell. In particular, for fixing mainly using pressure, the above configuration has no effect of dispersing stress, and the effect is small. Further, it is described that wax and other external additives (titanium oxide, etc.) can be blended, but there is no particular characteristic description.

  Therefore, in order to solve the above problems, the present invention provides a toner that is sufficiently plastically deformable even at a low pressure and has excellent fixability when performing pressure fixing under non-heating or low temperature conditions. An object of the present invention is to provide an image forming apparatus using toner.

  In order to solve the above problems, a toner according to the present invention contains a cyclic olefin resin, a wax, and hard particles, and the blending amount of the wax is 15 wt% to 30 wt% with respect to the whole toner. And the blending amount of the hard particles is 15% by weight to 30% by weight with respect to the whole toner.

  According to the above configuration, by mixing wax and hard particles in the cyclic olefin resin under predetermined conditions, the hardness of the toner is lowered, and the stress applied to the toner is dispersed to the surroundings, so that the plastic is sufficiently plastic even at a low pressure. A toner that is deformable and has excellent fixability can be obtained.

  The wax is blended in an amount of 15 to 30% by weight with respect to the whole toner. When the blending amount of the wax is less than the above range, it becomes difficult to plastically deform the entire toner, and when the blending amount of the wax is more than the above range, the storage stability of the toner and the pigment may be adversely affected. As the wax, it is preferable to use an ester wax mainly composed of a fatty acid ester compound.

  Since the ester wax has a relatively low compatibility with the cyclic olefin resin, the amount of the wax to be melted with respect to the fixing load increases, and a good fixing property can be obtained. In addition, it has an advantage of excellent storage stability as a toner.

  Ester waxes include natural waxes such as carnauba wax, candelilla wax, rice wax, and montan wax, as well as synthetic waxes such as methyl laurate, methyl myristate, methyl palmitate, methyl stearate, and butyl stearate. can do. Among ester waxes, carnauba is preferable, and a wax component collected from sunflower seeds is more preferable.

  The shape of the wax is preferably substantially spherical when dispersed in the toner. Usually, when a large amount of a release agent is blended, the dispersion shape receives a force in the rotation direction of the kneader, so that it tends to be an elongated rod shape. In that case, when the toner is stressed, the function of stress dispersion by the release agent becomes insufficient. However, when the shape is substantially spherical, the stress concentration can be sufficiently diffused, and good fixability can be obtained. In order to make the dispersed particles substantially spherical, for example, the toner is gradually cooled (annealed) after discharging from the kneader, or heated and cooled after normal cooling.

  The blending amount of the hard particles with respect to the whole toner is preferably 15% by weight to 30% by weight. If the blending amount of the hard particles is less than 15% by weight, the entire toner may not be affected. If the blending amount is more than 30% by weight, the elastic properties are lost and the fixability may be deteriorated. .

  By distributing hard particles in the toner, when a load is applied to the toner, the cyclic olefin resin slips at the interface between the cyclic olefin resin and the hard particles, and the cyclic olefin resin easily flows, so-called strain softening phenomenon occurs. . Therefore, it is preferable that the interface between the cyclic olefin resin and the hard particles is weak.

  The hard particles may be subjected to fatty acid treatment. That is, by subjecting the hard particles to a surface treatment with a fatty acid or a metal salt of a fatty acid, the surface of the hard particles can be made hydrophobic, thereby improving the dispersibility of the hard particles in the toner.

  In the image forming apparatus using the toner described above, after the toner is placed on the recording member, the toner is fixed under a low linear pressure of 5 kgf / cm to 30 kgf / cm and under non-heating or low temperature conditions. It becomes possible. Therefore, power consumption can be suppressed, and further, it is possible to shorten the time from starting up until image formation becomes possible.

  As described above, according to the present invention, it contains a cyclic olefin resin, a wax, and hard particles, and the blending amount of the wax is 15% by weight to 30% by weight with respect to the whole toner. Since the blending amount of the particles is 15% by weight to 30% by weight with respect to the whole toner, it is possible to obtain a toner that can be sufficiently plastically deformed even under low pressure under non-heating or low temperature conditions.

Schematic showing the main part of the image forming apparatus of the present invention Schematic diagram showing the dispersion state of wax and hard particles in the toner

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic view showing a main part of the image forming apparatus of the present invention. The image forming apparatus includes a fixing device having a fixing roller 1 and a pressure roller 2. In the image forming apparatus of the present embodiment, the toner 3 is transferred between the fixing roller 1 and the pressure roller after the image of the toner 3 is transferred to the recording member P by an intermediate transfer belt (not shown). Three images are fixed on the recording member P.

  An unfixed toner image is, for example, a toner contained in a developer such as a non-magnetic one-component developer containing a non-magnetic toner, a non-magnetic two-component developer containing a non-magnetic toner and a carrier, and a magnetic developer containing a magnetic toner. Formed with.

  Next, the toner material will be described. A cyclic olefin resin is used as the main resin 4 as a binder resin for the toner. That is, it is possible to mix other types of resins in addition to the cyclic olefin resin as the binder resin, but in that case, the cyclic olefin resin should have the largest compounding amount in the entire binder resin. . More preferably, the blending amount of the cyclic olefin resin with respect to the entire binder resin is 50% by weight or more. The cyclic olefin resin is nonpolar and can contain a large amount of a dispersant such as wax. The olefin resin used is described in detail in JP-A-2000-066438.

  The olefin polymer having a cyclic structure as the binder resin is a lower alkene having 2 to 12, preferably 2 to 6 carbon atoms, for example, an α-olefin such as ethylene, propylene and butylene (acyclic olefin in a broad sense). ) And cyclic and / or polycyclic compounds having 3 to 17, preferably 5 to 12 carbon atoms and having at least one double bond such as norbornene, tetracyclododecene, dicyclopentadiene, cyclohexene (cyclic ( Cyclo) olefin), particularly preferably a copolymer with norbornene or tetracyclododecene, which is colorless and transparent and has a high light transmittance.

  Olefin-based polymers having this cyclic structure include, for example, metallocene-based catalysts, Ziegler-based catalysts, and metathese polymerizations, that is, heavy polymers using catalysts for double bond opening and ring-opening polymerization reactions. It is a polymer obtained by a legal method. Examples of the synthesis of the olefin polymer having this structure include JP-A-5-339327, JP-A-5-9223, JP-A-6-271628, European Patent Application Publication (A) No. 203799, No. 407870, No. 283164, No. 156464, JP-A-7-253315, and the like.

  According to these, one or more monomers of the above cyclic olefin are optionally combined with one of the above acyclic olefin-monomers and -78 to 150 ° C., preferably 20 to 80 ° C. and a pressure of 0.01 to 64 bar and an aluminoxane. It is obtained by polymerizing in the presence of a catalyst comprising at least one metallocene comprising, for example, zirconium or hafnium. Other useful polymers are described in European Patent Application (A) 317262, and hydrogenated polymers and copolymers of styrene and dicyclopentadiene can also be used.

  Since the metallocene catalyst is activated in a state where the metallocene catalyst is dissolved in the inert hydrocarbon of the aliphatic or aromatic hydrocarbon, for example, the metallocene catalyst is dissolved in toluene, and the preliminary activity and reaction are performed in a solvent. The important properties of an olefin polymer having a cyclic structure are softening point, melting point, viscosity, dielectric properties, non-offset temperature range and transparency. These can be advantageously adjusted by the choice of monomer / comonomer, ie intermonomer ratio in the copolymer, molecular weight, molecular weight distribution, hybrid polymer, blends and additives.

  In addition, the reaction charge molar ratio of the acyclic olefin and the cyclic olefin can be varied in a wide range depending on the olefin polymer having a target cyclic structure, preferably 50: 1 to 1:50, particularly preferably. Is adjusted from 20: 1 to 1:20.

  For example, when the copolymer component is charged with a total of two compounds, ethylene as an acyclic olefin and norbornene as a cyclic olefin, the glass transition point (Tg) of an olefin polymer having a cyclic structure as a reaction product. Is greatly affected by these charging ratios, and when the norbornene content is increased, Tg tends to increase. For example, when the content of norbornene is about 60% by weight, Tg is about 60 to 70 ° C.

  When norbornene is used as the cyclic olefin, the norbornene content of the cyclic olefin resin is preferably 55% by weight to 65% by weight. The glass transition point of the cyclic olefin resin changes depending on the norbornene content. Therefore, if the norbornene content is lower than the above range, the toner storage stability may be deteriorated. If the norbornene content is higher than the above range, the toner elasticity may be too high.

  Cyclic olefin resin was mixed with polyamide resin, polybutylene terephthalate, polylactic acid or other alcohol, amine, isocyanate, epoxy group resin or the like, and a reactive resin such as reactive olefin resin. Things can also be used. As the reactive olefin resin, for example, GMA-modified polyethylene, polyethylene resin, ethylene / propylene copolymer resin, polyphenyl ether resin, and the like may be mixed at a predetermined ratio.

  Any colorant can be used, for example, carbon black, aniline black, acetylene black, naphthol yellow, hansa yellow, rhodamine lake, alizarin lake, bengara, phthalocyanine blue and indanthrene blue. One type of colorant may be used alone, or two or more types may be used in combination. The colorant is appropriately selected according to the color required for the toner.

  By containing a charge control agent, the charging characteristics of the toner can be controlled. Examples of the charge control agent include quaternary ammonium compounds, metal complexes of monoazo dyes, nitrohumic acid and its salts, metal complexes with metals such as salicylic acid, chromium or iron, and amino compounds. A material known as an organic dye can also be used as a charge control agent. One charge control agent may be used alone, or two or more charge control agents may be used in combination.

  The wax is blended in an amount of 15 to 30% by weight with respect to the whole toner. Various types of waxes (mold release agents) include ester waxes; aliphatic hydrocarbon waxes such as paraffin wax, polyolefin wax, Fischer-Tropsch wax, and microcrystalline wax; and polyurethane waxes such as low molecular weight polyurethane. Although it can be used, as described above, it is preferable to use an ester wax. One type of wax may be used alone, or two or more types may be used in combination. In this case, it is preferable to mix the fatty acid ester compound as a main component.

  The weight average molecular weight of the wax measured by gel permeation chromatography (GPC) is preferably 5000 or less, and more preferably 1000 or less. By reducing the molecular weight, it is possible to reduce the hardness of the toner, and even if the pressure is low, the toner can be plastically deformed over the entire surface, thereby exhibiting excellent fixability. The wax is preferably solid in the toner use temperature range, and for that purpose, the weight average molecular weight of the wax is preferably 500 or more.

  Examples of the hard particles include titanium oxide, calcium carbonate, silica, alumina, and clay. Of these, calcium carbonate is particularly suitable because of its excellent particle size, shape and dispersibility. The blending amount of the hard particles with respect to the whole toner is preferably 15% by weight to 30% by weight.

  FIG. 2 is a schematic view showing a dispersion state of wax and hard particles in the toner. As shown in the figure, the toner 3 according to the present invention has the wax 5 and the hard particles 6 uniformly dispersed in the cyclic olefin resin that is the main resin 4. Plastic deformation is possible, and excellent fixability can be obtained.

  Next, a method for manufacturing the toner 3 will be described. In the production of toner by a pulverization method, a toner composition containing a binder resin, a colorant, wax, hard particles and other additives is dry-mixed with a mixer and then melt-kneaded with a kneader. The kneaded product obtained by melt kneading is cooled and solidified, and the solidified product is pulverized by a pulverizer. Thereafter, particle size adjustment such as classification is performed as necessary to obtain a powdered toner.

  Known mixers can be used. For example, Henschel mixer (trade name, manufactured by Mitsui Mining Co., Ltd.), Super mixer (trade name, manufactured by Kawata Co., Ltd.), Mechano Mill (trade name, manufactured by Okada Seiko Co., Ltd.), An airflow mixer such as a hybridization system (trade name, manufactured by Nara Machinery Co., Ltd.) can be used.

  Known kneaders can be used, and examples thereof include general kneaders such as a twin-screw extruder, a three-roller, and a lab blast mill. More specifically, for example, TEM-100B (trade name, manufactured by Toshiba Machine Co., Ltd.), PCM-65 / 87, PCM-30 (all of which are trade names, manufactured by Ikegai Co., Ltd.) or the like. Extruder, Needex (trade name, manufactured by Mitsui Mining Co., Ltd.) and other open roll type kneaders. Among these, a twin screw extruder is preferable.

As the pulverizer, for example, a jet-type pulverizer that pulverizes using a supersonic jet stream or a solidified material is introduced into a space formed between a rotor (rotor) and a stator (liner) that rotate at high speed. And an impact type pulverizer for pulverization.
For the classification, a known classifier capable of removing the excessively pulverized toner base particles by classification using centrifugal force and wind force can be used, and examples thereof include a swirl type wind classifier (rotary wind classifier).

  As described above, the toner to which an external additive is added as required can be used as a one-component developer without adding a carrier, or can be mixed with a carrier and used as a two-component developer. When used as a one-component developer, toner that has been frictionally charged with a developing sleeve using a blade and a fur brush is attached onto the sleeve, thereby conveying the toner and forming an image. When used as a two-component developer, the toner of the present invention is used with a carrier. Since the one-component developer and the two-component developer contain the toner capable of maintaining a stable charging performance in a high humidity environment, the two-component developer has high charging stability even in a high humidity environment.

  As the carrier, a known carrier can be used, for example, a resin-coated carrier in which iron or copper, zinc, nickel, cobalt, manganese, chromium or the like alone or a composite ferrite and carrier toner base particles are surface-coated with a coating substance, or Examples thereof include a resin-dispersed carrier in which magnetic particles are dispersed in a resin.

  Known coating materials can also be used, such as polytetrafluoroethylene, monochlorotrifluoroethylene polymer, polyvinylidene fluoride, silicon resin, polyester resin, metal compound of ditertiary butylsalicylic acid, styrene resin, acrylic resin, Examples include polyacid, polyvinyllar, nigrosine, aminoacrylate resin, basic dye, basic dye lake, silica fine powder, and alumina fine powder.

  By using the toner of the present invention described above in the image forming apparatus according to the present invention, the pressure between the fixing roller 1 and the pressure roller 2 is a low pressure of 5 kgf / cm to 30 kgf / cm, and for example, It is possible to perform pressure fixing at a temperature as low as 25 ° C. or less without heating. As a result, power consumption required for heating can be suppressed, and the time required to start up the main body switch from the image forming apparatus can be shortened.

  In this example, various toners were prepared, and the formed toner was used to actually form an image with an image forming apparatus, and the toner fixability and storage stability were evaluated.

[Production of toner]
A cyclic olefin resin is used as a binder resin, and a toner composition in which a wax, hard particles, a pigment (carbon black), and a charge control agent (manufactured by Nippon Carlit Co., Ltd .: LR-147) are mixed is mixed with a kneader. Were melt kneaded. The kneaded product was cooled and solidified, and then the solidified product was pulverized by a pulverizer and the particle size was adjusted to obtain a toner. The cyclic olefin resin was obtained by reacting both as described above using ethylene as the acyclic olefin and norbornene as the cyclic olefin. A total of four types of cyclic olefin resins having a norbornene content of 50, 55, 60, 65, and 70% by weight were prepared by changing the charged amounts of ethylene and norbornene.

  As the wax, there are three types of ester waxes: a fatty acid ester having a weight average molecular weight of 600 (WEP-2 manufactured by NOF Corporation), a fatty acid ester having a weight average molecular weight of 980, and a fatty acid ester having a weight average molecular weight of 2500. In addition to the synthetic wax, carnauba wax and a wax component (ESTEC-0015 manufactured by Nippon Seiwa Co., Ltd.) collected from sunflower seeds were used. In addition, Fischer-Tropsch wax (Sazol C80 manufactured by Sazol Wax) was used as the aliphatic hydrocarbon wax.

  In addition, as the “fatty acid ester having a weight average molecular weight of 600”, two types of the dispersed particles in the toner having a substantially spherical shape and an elongated rod shape were used. That is, the toner composition containing the “fatty acid ester” is kneaded with a kneading machine and then cooled as usual, and then solidifies in the stretched state during extrusion, so that the shape of the wax particles in the toner becomes a long and narrow bar. When it is slowly cooled later, the shape of the wax particles in the toner is substantially spherical. The effect of the shape was evaluated by using the same kind of wax particles obtained in this way and having different shapes.

As hard particles, in addition to calcium carbonate, four types of alumina, titanium oxide, and silica were used. Two types of calcium carbonate were used: a fatty acid treated product and a fatty acid untreated product. Specific contents of the hard particles are as follows.
・ Calcium carbonate (Fatty acid processed product): Shiraishi Kogyo CCR
・ Calcium carbonate (untreated fatty acid product): Brilliant-1500 manufactured by Shiroishi Kogyo Co., Ltd.
・ Alumina: Nippon Aerosil C805
・ Titanium oxide: ST-550R manufactured by Titanium Industry Co., Ltd.
Silica: RX200 manufactured by Nippon Aerosil Co., Ltd.

  Various combinations of the above raw materials were used for No. 1 to 21 toners were prepared and evaluated. Specific blending and evaluation results are shown in Table 1. In the table, “%” in the columns of “blending amount”, “norbornene content”, “carbon black” and “LR-147” means “% by weight”. The indication of “molecular weight” means “weight average molecular weight”.

[Evaluation test]
(1) Fixability test As shown in Table 1, image formation was performed with an image forming apparatus using each produced toner, and the fixability was evaluated. As the image forming apparatus, a fixing roller and a pressure roller are both made of an iron material having a diameter of 40 mm and having a hard chrome plating on the surface. Although no halogen lamp is arranged in the fixing roller, a heating means such as a halogen lamp may be provided in order to improve the fixing property. In this embodiment, a linear pressure of 10 kgf / cm is applied between the fixing roller and the pressure roller, the fixing temperature is 25 ° C., the maximum fixing speed is 225 mm / sec, and the maximum copying speed is 50 sheets / minute (A4 horizontal feed). .

  The toner is fixed to A4 test paper with black solid, lightly folded so that the black solid part of the fixed test paper is bent, and a fold line is rolled by rolling a cylindrical roller of 1000 g in diameter 10 cm and height (width) 2 cm. After making, the crease of the recording paper was widened, and the toner that had fallen off the crease was wiped off with a clean waste cloth. Evaluation was made into five steps. Specific criteria are as shown below.

Evaluation Content 5 ... The width of the white part of the crease (the toner dropout part) is 0.1 mm or less 4 ... The width of the white part of the crease is 0.2 mm or less 3 ... The width of the white part of the crease is 0.3 mm or less 2 ... The crease The width of the white part is 0.4 mm or less 1... The width of the white part of the crease is 0.5 mm or less. As described above, the fixability has the highest evaluation in evaluation 5 and the evaluation in evaluation 1 has the lowest evaluation. -3 means that there is no practical problem, that is, an example level, and evaluations 2-1 mean that there is a practical problem, that is, a comparative example level.

(2) Preservability 20 g of toner is placed in a cylindrical aluminum container having a diameter of 3 cm and a height of 10 cm, left in a constant temperature bath at 60 ° C. for 5 hours, and then subjected to 400 mesh ultrasonic sieving to see if toner aggregates are generated. I investigated. Evaluation was made into five steps. Specific criteria are as shown below.

Evaluation Content 5 ... Mesh remaining rate is less than 2% 4 ... Mesh remaining rate is 2% or more and less than 5% 3 ... Mesh remaining rate is 5% or more and less than 10% 2 ... Mesh remaining rate is 10% or more and less than 20% 1 ... Mesh remaining ratio is 20% or more As described above, the fixability is rated 5 most highly, evaluation 1 is the least evaluated, and evaluations 5 to 3 are levels with no practical problems, that is, implementation. It means that it is an example level, and evaluations 2-1 mean that it is a practically problematic level, that is, a comparative example level.

[Evaluation results]
From Table 1, in the toner using ester wax as the wax and calcium carbonate as the hard particles, the blending amount of the wax and the hard particles is 15% by weight to 30% by weight with respect to the whole toner. Nos. 1 to 3, Nos. 6 to 14, Nos. And Nos. 17 to 21 (hereinafter simply abbreviated as No.) were at a level where there was no problem in both the fixability and the storage stability.

  On the other hand, the blending amount of the wax with respect to the whole toner is outside the range of 15% by weight to 30% by weight, No. 4-5, and the blending amount of the hard particles with respect to the whole toner is outside the range of 15% by weight to 30% by weight. About .15-16, it turns out that either the characteristic of fixing property or preservability is an inadequate level.

  Regarding the shape of the wax, No. 1 in which the shape of the wax particles in the toner is substantially spherical is superior to the No. 20 in which the shape of the wax particles is rod-like, and the fixability is superior. In addition, No. 1 and No. 21 in which the weight average molecular weight of the wax is 1000 or less are more excellent in fixing property than No. 6 in which the weight average molecular weight of the “fatty acid ester” wax is 2500.

  As for the type of wax, No. 1 using an ester wax is superior in fixing property to No. 9 using a non-ester wax. Furthermore, among the ester waxes, No. 19 using the wax component collected from sunflower seeds is superior to both No. 1 using “fatty acid ester” in terms of both fixability and storage stability. .

  As for the hard particles, the former is more excellent in the fixability in No. 1 using calcium carbonate and No. 11 and No. 12 using alumina, titanium oxide and silica other than calcium carbonate. Further, the hard particles (No. 1) subjected to the fatty acid treatment are superior in fixing property than the surface treated (No. 7).

DESCRIPTION OF SYMBOLS 1 Fixing roller 2 Pressure roller 3 Toner 4 Main resin 5 Wax 6 Hard particle

Claims (6)

It contains a cyclic olefin resin, a wax, and hard particles, and the blending amount of the wax is 15% by weight to 30% by weight based on the whole toner, and the blending amount of the hard particles is based on the whole toner. A toner comprising 15% by weight to 30% by weight. The toner according to claim 1, wherein the wax is an ester wax. The toner according to claim 1, wherein the shape of the wax is substantially spherical when dispersed in the toner. The toner according to claim 1, wherein the hard particles are calcium carbonate. The toner according to claim 4, wherein the calcium carbonate is treated with a fatty acid. An image forming apparatus, wherein the toner according to claim 1 is placed on a recording member and fixed at a pressure of 5 kgf / cm to 30 kgf / cm.

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