Toner, method for manufacturing toner, developer, toner storage unit, process cartridge, image forming apparatus, and image forming method.

Abstract

To provide a toner that can achieve both low temperature fixability and blocking resistance.SOLUTION: A toner according to an embodiment of the present invention contains at least a binder resin, a mold release agent, and a partially hydrogenated petroleum resin. The partially hydrogenated petroleum resin has a glass-transition temperature of 70°C or more and 90°C or less. The mold release agent has a melting point of 85°C or more and 90°C or less. The toner has a glass-transition temperature of 60°C or less.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a toner, a method for producing a toner, a developer, a toner containing unit, a process cartridge, an image forming apparatus, and an image forming method. [Background Art]

[0002] Conventionally, in electrophotographic apparatuses, electrostatic recording apparatuses and the like, electric latent images or magnetic latent images are visualized with an electrostatic latent image developing toner (also referred to as "toner" in the present invention). For example, in electrophotography, an electrostatic latent image is formed on a photoconductor, then the electrostatic latent image is developed with toner to form a toner image. The toner image is usually transferred onto a recording medium such as paper, and then fixed by a method such as heating.

[0003] In recent years, in consideration of environmental impact, there has been a demand for the development of toners that are aware of SDGs. For this reason, there are increasing demands for low-temperature fixability of toners. This is aimed at achieving energy saving by reducing the energy required for fixing.

[0004] As a method for achieving both improvement in low-temperature fixability and improvement in durability of toners, toners using petroleum resin as a grinding aid have been proposed. Among these, a technique of using hydrogenated petroleum resin (also referred to as "hydrogenated petroleum resin" in the present invention) in combination with a release agent is already known. Patent Document 1 discloses an electrophotographic toner characterized in that, for the purpose of providing an electrophotographic toner that achieves reduced particle diameter, high durability and oilless properties without impairing productivity, a low molecular weight thermoplastic resin is added as a grinding aid in addition to a binder resin and a release agent. Furthermore, Patent Document 1 defines a kneading method for producing an electrophotographic toner, and also proposes that the effect is exerted by limiting the ranges of the number average molecular weight, softening point and glass transition point of the grinding aid used. [Summary of the Invention] [Problem to be Solved by the Invention]

[0005] However, toners using the above-mentioned hydrogenated petroleum resins had a problem: improved low-temperature fixability came at the cost of reduced blocking resistance, making it impossible to achieve both simultaneously.

[0006] The present invention aims to provide a toner that enables both improved low-temperature fixability and resistance to blocking. [Means for solving the problem]

[0007] The toner of the present invention, which solves the above problems, has the configuration described below. A toner comprising at least a binder resin, a release agent, and a partially hydrogenated petroleum resin, The aforementioned partially hydrogenated petroleum resin teeth, Glass transition temperature is between 70°C and 90°C The weight-average molecular weight is between 2000 and 4000, and the T1 / 2 is 145°C or higher. And, The release agent has a melting point of 85°C or higher and 90°C or lower. A toner having a glass transition temperature of 60°C or lower. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide a toner that enables both improved low-temperature fixability and improved blocking resistance. [Brief explanation of the drawing]

[0009] [Figure 1] This is a schematic diagram showing an example of an image forming apparatus. [Figure 2] This is a cross-sectional view showing the configuration of a process cartridge, which is one embodiment of the toner storage unit according to the present invention. [Modes for carrying out the invention]

[0010] The toner and the like according to the present invention will be described in detail below. However, the present invention is not limited to the embodiments shown below, and can be modified, added, altered, or deleted to the extent that a person skilled in the art can conceive of it. Any embodiment that achieves the function and effects of the present invention is included within the scope of the present invention.

[0011] (toner) The toner of the present invention comprises at least a binder resin, a release agent, and a partially hydrogenated petroleum resin. Partially hydrogenated petroleum resin refers to a petroleum resin that has been partially hydrogenated. <Release agent> The aforementioned release agent may have a melting point of 85°C or higher and 90°C or lower. In the following, a release agent with a melting point of 85°C or higher and 90°C or lower will also be referred to as a "high-melting-point wax." A release agent with a melting point of 85°C or higher provides good heat resistance for storage. On the other hand, a release agent with a melting point of 90°C or lower allows for sufficient low-temperature fixation. Furthermore, it is preferable that the release agent be a hydrocarbon-based wax. Using a hydrocarbon-based wax as the release agent suppresses the generation of volatile organic compounds (VOCs), which can improve issues such as clogging of the machine's filters. Examples of hydrocarbon waxes include paraffin wax, sazole wax, polyethylene wax, polypropylene wax, Fischer-Tropsch wax, and polyolefin waxes such as microcrystalline wax, and two or more types may be used in combination.

[0012] <Partially hydrogenated petroleum resin> Partially hydrogenated petroleum resins should have a glass transition temperature (Tg) of 70°C or higher and 90°C or lower. A glass transition temperature of 70°C or higher results in good toner blocking resistance and storage performance. On the other hand, a glass transition temperature of 90°C or lower prevents deterioration of low-temperature fixing performance and hot offset. From these viewpoints, a glass transition temperature of 75°C or higher and 85°C or lower is more preferable for partially hydrogenated petroleum resins. Any partially hydrogenated petroleum resin having a glass transition temperature of 70°C or higher and 90°C or lower can be used as long as it is a resin hydrogenated based on a conventional petroleum resin.

[0013] The weight average molecular weight of the partially hydrogenated petroleum resin is preferably 2000 or more and 4000 or less. When the weight average molecular weight of the partially hydrogenated petroleum resin is 2000 or more and 4000 or less, the low-temperature fixability and heat resistance of the toner can be ensured.

[0014] The T1 / 2 of the partially hydrogenated petroleum resin is preferably 145°C or higher. When the T1 / 2 of the partially hydrogenated petroleum resin is 145°C or higher, the blocking resistance of the toner can be ensured. For measurement of T1 / 2, use a flow tester (manufactured by Shimadzu Corporation, CFT-500D), apply a load of 1.96 MPa via a plunger while heating 1 g of a sample at a temperature increase rate of 6°C / min, extrude the sample from a nozzle with a diameter of 1 mm and a length of 1 mm, plot the plunger displacement of the flow tester against temperature, and define the temperature at which half of the sample has flowed out as T1 / 2.

[0015] As a method for producing the partially hydrogenated petroleum resin, first a cyclopentadiene-based compound and a vinyl aromatic compound are polymerized. At that time, by controlling the reaction time, a polymer with a varied molecular weight can be obtained. Then, partially hydrogenated petroleum resin can be produced by hydrogenating the obtained polymer in the presence of a hydrogenation catalyst. Further, by changing the pressure in the presence of a hydrogenation catalyst, partially hydrogenated petroleum resins with varied Tg, molecular weight, and hydrogenation ratio can be produced. The hydrogenation ratio of the partially hydrogenated petroleum resin is not particularly limited, but is preferably about 30% or more and 70% or less, more preferably about 40% or more and 60% or less.

[0016] In the toner of the present invention, the partially hydrogenated petroleum resin and high-melting-point wax are added to the toner material, so that both low-temperature fixability and blocking resistance are improved compared to a toner formulated by adding the high-melting-point wax alone. In short, the toner is characterized in that the use of the partially hydrogenated petroleum resin, which is a low-molecular-weight substance, improves the low-temperature fixability of the toner, and when used in combination with the high-melting-point wax, the partially hydrogenated petroleum resin having high heat resistance during fixing assists in solidification of the wax, thereby improving the blocking resistance.

[0017] <Binder Resin> As the binder resin contained in the toner of the present invention, the following materials can be used. The binder resin contains an amorphous resin, and may optionally contain a crystalline resin. The amorphous resin is not particularly limited and can be appropriately selected according to the purpose. Examples of selectable amorphous resins include acrylic resins, styrene-acrylic resins, polyester resins, and epoxy resins, with polyester resins being preferred. Two or more types may be used in combination as needed.

[0018] The amorphous polyester resin is not particularly limited and can be appropriately selected according to the purpose, and examples thereof include polycondensed polyester resins synthesized from polyhydric alcohols and polyhydric carboxylic acids.

[0019] The amorphous polyester resin is not particularly limited and can be appropriately selected according to the purpose, but an amorphous polyester resin containing a divalent aliphatic alcohol component and a polyvalent aromatic carboxylic acid component as constituent components is preferred. Examples of the polyhydric alcohol include divalent diols, and polyols having a valence of 3 to 8 or higher.

[0020] There are no particular restrictions on the divalent diol, and it can be appropriately selected depending on the purpose. Examples include aliphatic alcohols (divalent aliphatic alcohols) such as linear aliphatic alcohols and branched aliphatic alcohols. Among these, aliphatic alcohols with 2 to 36 carbon atoms in the chain are preferred, and linear aliphatic alcohols with 2 to 36 carbon atoms in the chain are more preferred. These may be used individually or in combination of two or more.

[0021] There are no particular restrictions on the linear aliphatic alcohols mentioned above, and they can be appropriately selected depending on the purpose. Examples 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, 1,18-octadecanediol, and 1,20-eicosanediol. Of these, ethylene glycol, 1,3-propanediol (propylene glycol), 1,4-butanediol, 1,6-hexanediol, 1,9-nonanediol, and 1,10-decanediol are preferred considering their availability. Among these, linear aliphatic alcohols with 2 to 36 carbon atoms in the chain are preferred.

[0022] Examples of polycarboxylic acids include dicarboxylic acids and polycarboxylic acids with a valency of 3 to 6 or more. Among these, polyvalent aromatic carboxylic acids are preferred.

[0023] The dicarboxylic acid is not particularly limited and can be appropriately selected depending on the purpose. Examples include aliphatic dicarboxylic acids and aromatic dicarboxylic acids. Examples of aliphatic dicarboxylic acids include linear aliphatic dicarboxylic acids and branched aliphatic dicarboxylic acids. Among these, linear aliphatic dicarboxylic acids are preferred.

[0024] The aliphatic dicarboxylic acid is not particularly limited and can be appropriately selected depending on the purpose. Examples include alkane dicarboxylic acids, alkenyl succinic acid, alkene dicarboxylic acids, and alicyclic dicarboxylic acids.

[0025] Examples of the aforementioned alkanedicarboxylic acids include alkanedicarboxylic acids having 4 to 36 carbon atoms. Examples of the aforementioned alkanedicarboxylic acids having 4 to 36 carbon atoms include succinic acid, adipic acid, sebacic acid, azelaic acid, dodecanedicarboxylic acid, octadecanedicarboxylic acid, and decylsuccinic acid.

[0026] Examples of the aforementioned alkenyl succinic acid include dodecenyl succinic acid, pentadecenyl succinic acid, and octadecenyl succinic acid.

[0027] Examples of the aforementioned alkenedicarboxylic acid include alkenedicarboxylic acids having 4 to 36 carbon atoms. Examples of the aforementioned alkenedicarboxylic acids having 4 to 36 carbon atoms include maleic acid, fumaric acid, and citraconic acid.

[0028] Examples of the alicyclic dicarboxylic acid include alicyclic dicarboxylic acids having 6 to 40 carbon atoms. Examples of the alicyclic dicarboxylic acid having 6 to 40 carbon atoms include dimer acids (dimerized linoleic acid).

[0029] The aforementioned aromatic dicarboxylic acid is not particularly limited and can be appropriately selected depending on the purpose. Examples include aromatic dicarboxylic acids having 8 to 36 carbon atoms. Examples of aromatic dicarboxylic acids having 8 to 36 carbon atoms include phthalic acid, isophthalic acid, terephthalic acid, t-butylisophthalic acid, 2,6-naphthalenedicarboxylic acid, and 4,4'-biphenyldicarboxylic acid.

[0030] Examples of polycarboxylic acids with a valency of 9 to 6 or more include aromatic polycarboxylic acids having 9 to 20 carbon atoms. Examples of aromatic polycarboxylic acids having 9 to 20 carbon atoms include trimellitic acid and pyromellitic acid.

[0031] Furthermore, as the dicarboxylic acid or the carboxylic acid with a valency of 3 to 6 or higher, acid anhydrides of the above-mentioned substances or alkyl esters having 1 to 4 carbon atoms may be used. Examples of alkyl esters having 1 to 4 carbon atoms include methyl esters, ethyl esters, and isopropyl esters.

[0032] The crystalline resin is not particularly limited and can be appropriately selected depending on the purpose. For example, acrylic resin, styrene-acrylic resin, polyester resin, epoxy resin, etc. can be selected, but polyester resin is preferred.

[0033] Crystalline polyester resins exhibit a thermal melting characteristic where viscosity decreases sharply near the fixing initiation temperature due to their high crystallinity. Therefore, the crystalline polyester resin does not melt until just before the melting initiation temperature, resulting in excellent heat resistance and storage properties. At the melting initiation temperature, the crystalline polyester resin melts, causing a sharp decrease in viscosity, allowing it to become compatible with the amorphous resin and fix. This results in a toner with excellent heat resistance and low-temperature fixing properties. Furthermore, a toner with a large release width, i.e., a large difference between the fixing lower limit temperature and the high-temperature offset occurrence temperature, is obtained.

[0034] There are no particular restrictions on the crystalline polyester resin, and it can be appropriately selected depending on the purpose. Examples include polycondensed polyester resins synthesized from polyhydric alcohols and polyhydric carboxylic acids. Alternatively, polyhydric anhydrides, lower alkyl esters with 1 to 3 carbon atoms, or halides of polyhydric carboxylic acids may be used instead.

[0035] Polyhydric alcohols are not particularly limited, but examples include diols and trihydric or higher alcohols, and two or more may be used in combination.

[0036] Examples of diols include saturated aliphatic diols. Examples of saturated aliphatic diols include linear saturated aliphatic diols and branched saturated aliphatic diols. Among these, linear saturated aliphatic diols are preferred because they enhance the crystallinity of the crystalline polyester resin, and linear saturated aliphatic diols with 2 to 12 carbon atoms are even more preferred because they are readily available.

[0037] Examples of saturated aliphatic diols 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, 1,18-octadecanediol, and 1,20-eicosanediol. Among these, ethylene glycol, 1,4-butanediol, 1,6-hexanediol, 1,8-octanediol, 1,10-decanediol, and 1,12-dodecanediol are preferred because they increase the crystallinity of the crystalline polyester resin and provide excellent sharp-melt properties.

[0038] Examples of alcohols with a hydride of 3 or higher include glycerin, trimethylolethane, trimethylolpropane, and pentaerythritol.

[0039] Polycarboxylic acids are not particularly limited, but examples include divalent carboxylic acids and trivalent or higher carboxylic acids.

[0040] Examples of divalent carboxylic acids include saturated aliphatic dicarboxylic acids such as oxalic acid, succinic acid, glutaric acid, adipic acid, superiric acid, azelaic acid, sebacic acid, 1,9-nonanedicarboxylic acid, 1,10-decanedicarboxylic acid, 1,12-dodecanedicarboxylic acid, 1,14-tetradecanedicarboxylic acid, and 1,18-octadecanedicarboxylic acid; and aromatic dicarboxylic acids such as phthalic acid, isophthalic acid, terephthalic acid, naphthalene-2,6-dicarboxylic acid, malonic acid, and mesaconic acid.

[0041] Examples of carboxylic acids with a valency of three or higher include 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, and 1,2,4-naphthalentricarboxylic acid.

[0042] Furthermore, the polycarboxylic acid may include a dicarboxylic acid having a sulfonic acid group. Also, the polycarboxylic acid may include a dicarboxylic acid having a carbon-carbon double bond.

[0043] The crystalline polyester resin preferably has structural units derived from linear saturated aliphatic dicarboxylic acids having 4 to 12 carbon atoms and structural units derived from linear saturated aliphatic diols having 2 to 12 carbon atoms. This results in a crystalline polyester resin with high crystallinity and excellent sharp melt properties. As a result, the low-temperature fixation properties of the toner can be improved.

[0044] The melting point of the crystalline polyester resin is preferably 60 to 90°C, and more preferably 60 to 80°C. A melting point of 60°C or higher improves the heat resistance of the toner, while a melting point of 90°C or lower improves the low-temperature fixing properties of the toner.

[0045] The weight-average molecular weight of the crystalline polyester resin is preferably 3,000 to 30,000, and more preferably 5,000 to 15,000. A weight-average molecular weight of 3,000 or more improves the heat-resistant storage properties of the toner, while a weight-average molecular weight of 30,000 or less improves the low-temperature fixing properties of the toner.

[0046] The acid value of the crystalline polyester resin is preferably 5 mg KOH / g or higher, and more preferably 10 mg KOH / g or higher. This improves the low-temperature fixation of the toner. On the other hand, the acid value of the crystalline polyester resin is preferably 45 mg KOH / g or lower. This improves the high-temperature offset resistance of the toner.

[0047] The hydroxyl value of the crystalline polyester resin is preferably 50 mgKOH / g or less, and more preferably 5 to 50 mgKOH / g. Having a hydroxyl value of 50 mgKOH / g or less in the crystalline polyester resin improves the low-temperature fixation and electrostatic properties of the toner.

[0048] The molecular structure of crystalline polyester resins can be confirmed by NMR measurements in solution or solid form, as well as by X-ray diffraction, GC / MS, LC / MS, and IR measurements. A simple method is to use infrared absorption spectroscopy, specifically 965±10 cm⁻¹. -1 or 990±10cm -1 Materials exhibiting absorption based on δCH (out-of-plane angular bending vibration) of olefins can be detected as crystalline polyester resins.

[0049] The content of crystalline polyester resin in the toner is preferably 3 to 20% by mass, and more preferably 5 to 15% by mass. A crystalline polyester resin content of 3% by mass or more improves the low-temperature fixing properties of the toner, while a content of 20% by mass or less improves the heat-resistant storage properties of the toner and suppresses the occurrence of image fogging.

[0050] <Coloring agent> The toner of the present invention may contain a coloring agent. There are no particular restrictions on the colorants used; they can be appropriately selected depending on the purpose. For example, carbon black, nigrosine dye, iron black, naphthol yellow S, Hansa yellow (10G, 5G, G), cadmium yellow, yellow iron oxide, ochre, yellow lead, titanium yellow, polyazo yellow, oil yellow, Hansa yellow (GR, A, RN, R), pigment yellow L, benzidine yellow (G, GR), permanent yellow (NCG), Vulcan fast yellow (5G, R), tartrazine lake, quinoline yellow lake, and anthrazane yellow BGL. Isoindolone Yellow, Bengara, Red Lead, Red Lead, Cadmium Red, Cadmium Mercury Red, Antimony Red, Permanent Red 4R, Para Red, Faise Red, Parachlor-orthonitroaniline Red, Risol Fast Scarlet G, Brilliant Fast Scarlet, Brilliant Carmine BS, Permanent Red (F2R, F4R, FRL, FRLL, F4RH), Fast Scarlet VD, Belkan Fast Rubin B, Brilliant Scarlet G, Risol Rubin GX, Permanent Red F5R, Brillia Bon Maroon 6B, Pigment Scarlet 3B, Bordeaux 5B, Toluidine Maroon, Permanent Bordeaux F2K, Helio Bordeaux BL, Bordeaux 10B, Bon Maroon Light, Bon Maroon Medium, Eosin Lake, Rhodamine Lake B, Rhodamine Lake Y, Alizarin Lake, Thioindigo Red B, Thioindigo Maroon, Oil Red, Quinacridone Red, Pyrazolone Red, Polyazo Red, Chrome Vermilion, Benzidine Orange, Perinon Orange, Oil Orange, Cobalt Blue, Cerulean Blue, Alkali Blue Lake, Peacock Blue Lake, Victoria Blue Lake, Metal-free Phthalocyanine Blue, Phthalocyanine Blue, Fast Sky Blue, Indanthrene Blue (RS, BC), Indigo, Ultramarine, Prussian Blue, Anthraquinone Blue, Fast Violet B, Methyl Violet Lake, Cobalt Purple, Manganese Purple, Dioxane Violet, Anthraquinone Violet, Chrome Green, Zinc Green, Chromium Oxide, Pyridian, Emerald Green, Pigment Green B, Naphthol Green B, Green Gold, Acid Green Lake,Examples include malachite green lake, phthalocyanine green, anthraquinone green, titanium dioxide, zinc oxide, and lithobone.

[0051] The toner of the present invention only needs to have a glass transition temperature of 60°C or lower. A glass transition temperature of 60°C or lower ensures sufficient low-temperature fixation.

[0052] (Toner manufacturing method) The toner manufacturing method of the present invention is a method for manufacturing the toner of the present invention as described above, comprising the steps of: mixing and melt-kneading at least a binder resin, a release agent, and a partially hydrogenated petroleum resin; and drying and then pulverizing the kneaded product obtained by the melt-kneading. A coloring agent can be included in the melt-mixing process. The binder resin, release agent, partially hydrogenated petroleum resin, and coloring agent can be the same as those described in the above description of the toner of the present invention. The method of melt-mixing and the method of pulverizing the mixed product after drying are not particularly limited, and known methods can be applied. The toner obtained by the toner manufacturing method of the present invention only needs to have a glass transition temperature of 60°C or lower.

[0053] (Developer) The developer of the present invention comprises at least the toner of the present invention, and optionally includes other components such as a carrier, which are selected as appropriate. Therefore, it has excellent transferability and electrostatic properties, and can stably form high-quality images. The developer may be a one-component developer or a two-component developer, but when used in high-speed printers that can handle the recent increase in information processing speed, a two-component developer is preferred because it extends the lifespan. When the aforementioned developer is used as a single-component developer, even when toner is balanced, there is little variation in the toner particle size, resulting in less toner filming onto the developing roller and less toner fusion onto components such as blades that thin the toner layer. This allows for good and stable development and image quality even during long-term agitation in the developing apparatus. When the aforementioned developer is used as a two-component developer, even with long-term toner balance cycles, there is little variation in toner particle size, and good and stable developability and images can be obtained even with long-term agitation in the developing device.

[0054] <Career> There are no particular restrictions on the carrier, and it can be appropriately selected according to the purpose, but one having a core material and a resin layer covering the core material is preferred.

[0055] -Core material- There are no particular restrictions on the material of the core material, and it can be appropriately selected according to the purpose. Examples include manganese-strontium materials with a density of 50 emu / g to 90 emu / g, and manganese-magnesium materials with a density of 50 emu / g to 90 emu / g. In order to ensure image density, it is preferable to use highly magnetized materials such as iron powder with a density of 100 emu / g or more, or magnetite with a density of 75 emu / g to 120 emu / g. Furthermore, it is preferable to use low-magnetized materials such as copper-zinc materials with a density of 30 emu / g to 80 emu / g, as this can mitigate the impact of the developer in a condensed state on the photoreceptor and is advantageous for improving image quality. These can be used individually or in combination of two or more.

[0056] There are no particular restrictions on the volume-average particle size of the core material, and it can be appropriately selected depending on the purpose, but 10 μm to 150 μm is preferred, and 40 μm to 100 μm is more preferred. If the volume-average particle size is less than 10 μm, there will be a large amount of fine powder in the carrier, which may reduce the magnetization per particle and cause carrier scattering. If it exceeds 150 μm, the specific surface area will decrease, which may cause toner scattering, and in full-color printing with many solid areas, the reproduction of solid areas may be particularly poor. When the toner is used in a two-component developer, it may be used in combination with the carrier. There are no particular restrictions on the amount of the carrier in the two-component developer, and it can be appropriately selected depending on the purpose, but 90 to 98 parts by mass and more preferably 93 to 97 parts by mass per 100 parts by mass of the two-component developer is preferred.

[0057] (Image forming apparatus and image forming method) The image forming apparatus of the present invention comprises at least an electrostatic latent image carrier, an electrostatic latent image forming means, and a developing means, and further comprises other means as necessary. The image forming method according to the present invention includes at least an electrostatic latent image formation step and a development step, and further includes other steps as necessary.

[0058] <Electrostatic latent image carrier> There are no particular restrictions on the material, structure, or size of the electrostatic latent image carrier, and can be appropriately selected from known materials. Examples of materials include inorganic photoreceptors such as amorphous silicon and selenium, and organic photoreceptors such as polysilane and phthalopolymethine. Among these, amorphous silicon is preferred in terms of long lifespan.

[0059] <Electrostatic latent image forming means and electrostatic latent image forming process> The electrostatic latent image forming means is not particularly limited as long as it is a means for forming an electrostatic latent image on the electrostatic latent image carrier, and can be appropriately selected according to the purpose. For example, it could be a means having at least a charging member for charging the surface of the electrostatic latent image carrier and an exposure member for exposing the surface of the electrostatic latent image carrier to an image. The electrostatic latent image formation step is not particularly limited as long as it is a step of forming an electrostatic latent image on the electrostatic latent image carrier, and can be appropriately selected according to the purpose. For example, it can be performed by charging the surface of the electrostatic latent image carrier and then exposing it in an image-like manner, and can be performed using the electrostatic latent image formation means.

[0060] <<Charged material and charging>> There are no particular limitations on the charging member, and it can be appropriately selected according to the purpose. Examples include contact chargers that are known themselves and equipped with conductive or semiconductive rollers, brushes, films, rubber blades, etc., and non-contact chargers that utilize corona discharge such as Corotron and Scorotron. The charging can be performed, for example, by applying a voltage to the surface of the electrostatic latent image carrier using the charging member. The shape of the charging member can be any form other than a roller, such as a magnetic brush or a fur brush, and can be selected according to the specifications and configuration of the image forming apparatus. The charging member is not limited to the contact-type charging member, but it is preferable to use a contact-type charging member because it reduces the amount of ozone generated from the charging member, thus providing an image forming apparatus.

[0061] <<Exposure component and exposure>> The exposure member is not particularly limited as long as it can expose the surface of the electrostatic latent image carrier, which has been charged by the charging member, in the manner of the image to be formed. It can be appropriately selected according to the purpose, and examples of such members include various exposure members such as copying optical systems, rod lens array systems, laser optical systems, and liquid crystal shutter optical systems. There are no particular restrictions on the light source used in the exposure member, and it can be appropriately selected according to the purpose. Examples include fluorescent lamps, tungsten lamps, halogen lamps, mercury lamps, sodium lamps, light-emitting diodes (LEDs), semiconductor lasers (LDs), electroluminescent devices (ELs), and other light-emitting materials in general. Furthermore, various filters such as sharp-cut filters, band-pass filters, near-infrared cut filters, dichroic filters, interference filters, and color temperature conversion filters can be used to illuminate only the desired wavelength range. The exposure can be performed, for example, by exposing the surface of the electrostatic latent image carrier in an image-like manner using the exposure member. In addition, in the present invention, a back-facing method may be employed in which the electrostatic latent image carrier is exposed in an image-like manner from the back side.

[0062] <Developing means and developing process> The developing means is not particularly limited as long as it is a developing means equipped with toner that develops the electrostatic latent image formed on the electrostatic latent image carrier to form a toner image which is a visible image, and can be appropriately selected according to the purpose. The development step is not particularly limited as long as it is a step of developing the electrostatic latent image formed on the electrostatic latent image carrier using toner to form a toner image, which is a visible image. It can be appropriately selected according to the purpose, for example, by the development means. The developing means is preferably a developing apparatus that includes an agitator that frictionally agitates and charges the toner, and a developer carrier that has a magnetic field generating means fixed inside and a rotatable developer carrier on which the developer containing the toner is carried.

[0063] The developer of the present invention can be suitably used for image formation by various known electrophotographic methods, such as magnetic one-component development methods, non-magnetic one-component development methods, and two-component development methods. Within the developing means, for example, the toner and the carrier are mixed and stirred, and the friction during this process causes the toner to become charged, which is then held in a brush-like state on the surface of a rotating magnetic roller, forming a magnetic brush. The magnetic roller is positioned near the electrostatic latent image carrier. Therefore, a portion of the toner that constitutes the magnetic brush formed on the surface of the magnetic roller moves to the surface of the electrostatic latent image carrier by electrical attraction. As a result, the electrostatic latent image is developed by the toner, and a visible image is formed on the surface of the electrostatic latent image carrier by the toner.

[0064] <Other means and other processes> Other means include, for example, transfer means, fixing means, cleaning means, static elimination means, recycling means, and control means. Other processes include, for example, a transfer process, a fixing process, a cleaning process, a static elimination process, a recycling process, and a control process.

[0065] <<Transfer means and transfer process>> The transfer means is not particularly limited as long as it is a means for transferring a visible image to a recording medium, and can be appropriately selected according to the purpose. However, a configuration having a first transfer means for transferring a visible image onto an intermediate transfer body to form a composite transfer image, and a second transfer means for transferring the composite transfer image onto a recording medium is preferred. The aforementioned transfer step is not particularly limited as long as it is a step of transferring a visible image to a recording medium, and can be appropriately selected according to the purpose. However, a preferred method is to use an intermediate transfer material, first transfer the visible image onto the intermediate transfer material, and then second transfer the visible image onto the recording medium. The transfer step can be performed, for example, by charging the photoreceptor using a transfer charger to create the visible image, and can be carried out by the transfer means.

[0066] In this configuration, if the image to be secondarily transferred onto the recording medium is a color image consisting of multiple toners, the transfer means can sequentially superimpose each toner onto the intermediate transfer body to form an image on the intermediate transfer body, and the intermediate transfer means can then secondarily transfer the image on the intermediate transfer body onto the recording medium in one go. There are no particular restrictions on the intermediate transfer material, and it can be appropriately selected from known transfer materials depending on the purpose. For example, a transfer belt is a suitable example.

[0067] The transfer means (the primary transfer means, the secondary transfer means) preferably includes at least a transfer device that exfoliates the visible image formed on the photoreceptor toward the recording medium. Examples of the transfer device include a corona discharge transfer device, a transfer belt, a transfer roller, a pressure transfer roller, and an adhesive transfer device. While plain paper is a typical recording medium, there are no particular restrictions as long as it can transfer the unfixed image after development. It can be appropriately selected according to the purpose, and PET bases for OHPs can also be used.

[0068] <<Fixing means and fixing process>> The fixing means is not particularly limited as long as it is a means for fixing the transferred image transferred to the recording medium, and can be appropriately selected according to the purpose, but a known heating and pressing member is preferred. Examples of the heating and pressing member include a combination of a heating roller and a pressing roller, and a combination of a heating roller, a pressing roller and an endless belt. The fixing step is not particularly limited as long as it is a step of fixing the visible image transferred to the recording medium, and can be appropriately selected according to the purpose. For example, it may be performed for each color of toner after it has been transferred to the recording medium, or it may be performed simultaneously for each color of toner in a stacked state.

[0069] The fixing process can be carried out by the fixing means. The heating temperature in the aforementioned heating and pressurizing member is usually preferably 80°C to 200°C. In addition, in the present invention, depending on the purpose, a known optical fuser may be used together with or in place of the fixing means, for example. There are no particular restrictions on the surface pressure in the fixing process, and it can be appropriately selected depending on the purpose, but 10 N / cm is recommended. 2 ~80 N / cm 2 It is preferable that this be the case.

[0070] <<Cleaning Methods and Cleaning Processes>> The cleaning means is not particularly limited as long as it is a means that can remove the toner remaining on the photoreceptor, and can be appropriately selected according to the purpose. Examples include magnetic brush cleaners, electrostatic brush cleaners, magnetic roller cleaners, blade cleaners, brush cleaners, and web cleaners. The cleaning process is not particularly limited as long as it is a process that can remove the toner remaining on the photoreceptor, and can be appropriately selected according to the purpose, for example, by the cleaning means.

[0071] <<Static elimination means and static elimination process>> The static elimination means is not particularly limited as long as it is a means of eliminating static electricity by applying a static elimination bias to the photoreceptor, and can be appropriately selected according to the purpose, for example, a static elimination lamp. The static elimination step is not particularly limited as long as it is a step of eliminating static electricity by applying a static elimination bias to the photoreceptor, and can be appropriately selected according to the purpose, for example, it can be carried out by the static elimination means.

[0072] <<Recycling methods and recycling processes>> The recycling means is not particularly limited as long as it is a means of recycling the toner removed by the cleaning process to the developing device, and can be appropriately selected according to the purpose, for example, known transport means. The recycling process is not particularly limited as long as it is a process of recycling the toner removed by the cleaning process to the developing device, and can be appropriately selected according to the purpose, for example, by the recycling means.

[0073] Next, one embodiment of a method for forming an image using the image forming apparatus of the present invention will be described with reference to Figure 1. Image forming apparatus 1 is a printer, but the image forming apparatus is not particularly limited as long as it is capable of forming images using toner from a copier, facsimile, multifunction printer, etc. The image forming apparatus 1 comprises a paper feeding unit 210, a transport unit 220, an image forming unit 230, a transfer unit 240, and a fuser unit 250. The paper feeding unit 210 includes a paper feed cassette 211 on which the paper to be fed P is stacked, and a paper feed roller 212 that feeds the paper P from the paper feed cassette 211 one sheet at a time.

[0074] The transport unit 220 includes a roller 221 that transports the paper P fed by the paper feed roller 212 toward the transfer unit 240, a pair of timing rollers 222 that hold the leading edge of the paper P transported by the roller 221 and wait, and send the paper to the transfer unit 240 at a predetermined timing, and a paper discharge roller 223 that discharges the paper P on which the color toner image has been fixed toward the paper discharge tray 224. The image-forming unit 230 comprises, at predetermined intervals and arranged sequentially from left to right in the figure, an image-forming unit Y that forms an image using a developer containing yellow toner, an image-forming unit C that uses a developer containing cyan toner, an image-forming unit M that uses a developer containing magenta toner, an image-forming unit K that uses a developer containing black toner, and an exposure unit 233.

[0075] Furthermore, when referring to any of the image forming units (Y, C, M, K), the term "image forming unit" is used. Furthermore, the developer contains toner and a carrier. The four image-forming units (Y, C, M, K) are essentially identical in their mechanical configuration, differing only in the developer they use. The transfer unit 240 includes a drive roller 241 and a driven roller 242, an intermediate transfer belt 243 that can rotate counterclockwise in the figure as the drive roller 241 is driven, primary transfer rollers (244Y, 244C, 244M, 244K) provided opposite the photoreceptor drum 231 with the intermediate transfer belt 243 in between, and secondary opposing rollers 245 and secondary transfer rollers 246 provided opposite the intermediate transfer belt 243 at the position where the toner image is transferred to the paper. The fuser unit 250 has a heater inside and is equipped with a pressure roller 252 that rotatably applies pressure to the fuser belt 251, which heats the paper P, to form a nip. This applies heat and pressure to the color toner image on the paper P, fixing the color toner image. The paper P with the fixed color toner image is ejected to the paper output tray 224 by the paper output roller 223, completing the image forming process.

[0076] (Toner storage unit) In this invention, a toner storage unit refers to a unit having the function of storing toner, in which toner is stored. Examples of the toner storage unit include a toner storage container, a developer, a process cartridge, and the like. A toner container refers to a container that holds toner. A developing unit refers to a device that has the means to store toner and develop it. A process cartridge is defined as a device that integrates at least an image carrier and a developing means, contains toner, and is detachable from an image forming apparatus. The process cartridge may further include at least one selected from a charging means, an exposure means, and a cleaning means.

[0077] By installing the toner storage unit of the present invention into an image forming apparatus and forming an image, the image is formed using the low-cost toner of the present invention, which has excellent durability, low-temperature fixability, pulverability during toner manufacturing, copy blocking resistance, and filming resistance. This provides the effect of obtaining high-quality images at a low cost.

[0078] <Processing Cartridge> The process cartridge according to the present invention is formed to be detachably attached to various image forming apparatuses and comprises at least an electrostatic latent image carrier that carries an electrostatic latent image, and a developing means that develops the electrostatic latent image carried on the electrostatic latent image carrier with the developer of the present invention to form a toner image. The process cartridge of the present invention may further comprise other means as needed. The developing means includes at least a developer storage section for containing the developer of the present invention, and a developer carrier for carrying and transporting the developer contained in the developer storage section. The developing means may further include a regulating member or the like to regulate the thickness of the carried developer. Figure 2 shows an example of a process cartridge according to the present invention. The process cartridge 110 includes a photoreceptor drum 10, a corona charger 58, a developer 40, a transfer roller 80, and a cleaning device 90. [Examples]

[0079] The present invention will be described in detail below with reference to examples, but the present invention is not limited to the following examples. In the following, unless otherwise specified, "parts" means "parts by mass" and "%" means "percent mass".

[0080] <Manufacturing of partially hydrogenated petroleum resins> Cyclopentadiene compounds and vinyl aromatic compounds were prepared and polymerized by reacting them. By varying the reaction time, polymers with various molecular weights were produced. Next, partially hydrogenated petroleum resins were produced by hydrogenating the polymers obtained by the reaction described above in the presence of a hydrogenation catalyst. Furthermore, by changing the pressure in the presence of the hydrogenation catalyst during hydrogenation, partially hydrogenated petroleum resins with various glass transition temperatures (Tg), weight-average molecular weights (Mw), and hydrogenation rates were produced. Table 1 shows the details of the partially hydrogenated petroleum resins manufactured.

[0081] [Table 1]

[0082] The hydrogenation rate of partially hydrogenated petroleum resins was calculated using proton NMR. Details are shown below. Approximately 0.1 g of the sample was mixed with 0.7 ml of deuterated chloroform (CDCl3), and after confirming that it had dissolved, it was placed in a φ5 mm NMR tube and used as the sample for NMR measurement. Measuring device: JEOL ECX-500 FT-NMR Measurement temperature: room temperature 1 H-NMR measurement conditions Measurement nucleus = 1H (500MHz), data points = 64K, observation width = 17ppm, number of integrations = 64 Measurement pulse = single pulse.jxp, 45° pulse, Relaxation Delay 5 seconds, offset = 8 ppm The hydrogenation rate of partially hydrogenated petroleum resin A was calculated as the ratio of the spectral area of ​​the aromatic ring signal before hydrogenation (between 6.5-7.5 ppm) to the spectral area of ​​the aromatic ring signal after hydrogenation (between 1.0-2.0 ppm).

[0083] <Release agent> The following materials were prepared as release agents, as shown in Table 2.

[0084] [Table 2]

[0085] Release agents A through C are hydrocarbon-based waxes, while release agent D is a non-hydrocarbon-based wax.

[0086] (Example 1) - Toner matrix particle preparation - 69 parts of amorphous polyester resin synthesized as described below 5.5 parts of crystalline polyester resin synthesized as described below Release agent A 5 parts Carbon black (#44, manufactured by Mitsubishi Chemical Corporation) 11 parts Azo iron compound (T-77, manufactured by Hodogaya Chemical Co., Ltd.) 1 part Partially hydrogenated petroleum resin B 10 parts

[0087] Amorphous polyester resin In a reaction vessel equipped with a condenser, a stirrer, and nitrogen inlet, the monomer species shown in Table 3 below and tetrabutoxytitanate as a condensation catalyst were added and reacted at 230°C for 6 hours under a nitrogen stream, while distilling off the water produced. Next, the reaction was carried out under reduced pressure of 5 mmHg to 20 mmHg for 1 hour to obtain the amorphous polyester resin used in the example. In the table, the "25 mol%" indicated for bisphenol A(2,2) propylene oxide represents the proportion of the alcohol component when the acid component and alcohol component are both 50 mol%.

[0088] [Table 3]

[0089] Crystalline polyester resin Fumaric acid and 1,6-hexanediol were placed in a 5L four-necked flask equipped with a nitrogen inlet tube, dehydration tube, stirrer, and thermocouple so that the OH / COOH ratio of the fumaric acid and 1,6-hexanediol was 0.9. The mixture was reacted with titanium tetraisopropoxide (500 ppm relative to the resin component) at 180°C for 10 hours, then the temperature was raised to 200°C and the reaction was continued for 3 hours, followed by a reaction at a pressure of 8.3 kPa for 2 hours to obtain the crystalline polyester resin used in the examples.

[0090] Following the above formulation, the toner raw materials were pre-mixed using a Henschel mixer (manufactured by Mitsui Miike Chemical Machinery Co., Ltd., FM20B), and then melted and kneaded at 120°C in a twin-shaft kneader (manufactured by Ikegai Co., Ltd., PCM-30). The resulting mixture was rolled to a thickness of 2.7 mm using rollers, cooled to room temperature using a belt cooler, and then coarsely ground to 200 μm to 300 μm using a hammer mill. Next, the material was finely ground using a supersonic jet pulverizer, LabJet (manufactured by Nippon Pneumatic Mfg. Co., Ltd.), and then classified using an airflow classifier (MDS-I, manufactured by Nippon Pneumatic Mfg. Co., Ltd.) while appropriately adjusting the louver opening to obtain the toner matrix particles of Example 1.

[0091] - Toner particle creation - To 100 parts by mass of the above-mentioned toner matrix particles, 1.00 part of silica fine particles 1 and 0.03 part of silica fine particles 2 were added and stirred and mixed in a Henschel mixer to produce toner particles 1. Developer 1 was prepared by uniformly mixing 5% toner particles 1 and 95% coating ferrite carrier using a turbler mixer (manufactured by Willy e Bakkofen (WAB)) at 48 rpm for 5 minutes. Using an image forming apparatus with the toner particles 1 and developer 1, the low-temperature fixability and heat resistance were evaluated according to the evaluation method described below.

[0092] <Evaluation of low-temperature fixation> The toner particles 1 and developer 1 were placed in a Ricoh Co., Ltd. copier (RICOH MPC 6003) and an image was printed. Adhesion amount: 0.4 mg / cm² 2 The solid image was printed onto paper (Ricoh Type 6200) through exposure, development, and transfer processes. The fixing speed was 256 mm / second. The fixing temperature was sequentially set at 5°C increments, and the lower fixing temperature at which cold offset did not occur (lower fixing temperature: low-temperature fixing performance) was measured. The NIP width of the fixing device was 11 mm. The evaluation criteria were as follows, with "◎" and "〇" indicating a pass. The results are shown in Table 4 below. -Evaluation Criteria for Low-Temperature Fixation- ◎: Below 120℃ ○: 120℃ or higher, less than 130℃ ×: Above 130℃

[0093] <Blocking resistance> The toner particles 1 and developer 1 were applied using a modified Ricoh Imagio Neo C600 digital full-color multifunction printer (line speed 280 mm / sec) to a deposition amount of 0.85 mg / cm². 2 A 4cm square solid image was formed, and fixing was performed with a NIP width of 10mm and a fixing roller temperature of 160℃. A 60g weight was placed on top of the two images with their fixed image surfaces overlapping, and the images were stored in a 70℃ constant temperature bath for 24 hours. After removal, they were cooled for more than one hour. The image condition and the sound of peeling were then checked when the two images were separated. The evaluation criteria were as follows, with "◎" and "〇" being considered passing grades. The results are shown in Table 4 below. [Evaluation Criteria] ◎: No image peeling, no peeling sound. ○: No image peeling, peeling sound present. ×: More than 11 areas of image peeling, peeling sound present.

[0094] <Evaluation of heat resistance and storage properties> The toner particles were stored at 50°C for 24 hours, and the penetration depth was measured according to JIS K2235 (25°C). A VR-5610 penetration meter (Shimadzu Corporation) was used to measure the penetration depth. The evaluation criteria are as follows, with a "〇" rating indicating a pass. -Evaluation criteria for heat resistance and storage properties- ○: 23.0mm or larger ×: Less than 23.0mm

[0095] <Clogged exhaust filter> The toner particles 1 and developer 1 were used to print 300,000 5% image area charts using a modified Ricoh Imagio Neo C600 digital full-color multifunction printer (line speed 280 mm / sec) under conditions of 25°C and 60% RH. The degree of clogging of the exhaust filter of the exhaust fan of the evaluation machine was then evaluated according to the following criteria. A "○" rating indicates a pass. [Evaluation Criteria] ○: Exhaust filter clogging is minimal and in good condition. ×: The exhaust filter is clogged and therefore defective.

[0096] (Examples 2-6, Comparative Examples 1-6) Except for the types of partially hydrogenated petroleum resin and release agent and the amount of crystalline polyester resin used in Example 1, toner particles and developers for Examples 2 to 6 and Comparative Examples 1 to 6 were manufactured in the same manner as in Example 1, as shown in Table 4 below. The low-temperature fixability and blocking resistance were evaluated using the method described above. The results are shown in Table 5 below.

[0097] [Table 4]

[0098] [Table 5]

[0099] The present invention relates to the toner described in (1) below, but includes the embodiments described in (2) to (10) below. (1) A toner comprising at least a binder resin, a release agent, and a partially hydrogenated petroleum resin, The glass transition temperature of the partially hydrogenated petroleum resin is 70°C or higher and 90°C or lower. The release agent has a melting point of 85°C or higher and 90°C or lower. A toner having a glass transition temperature of 60°C or lower. (2) The release agent is the toner described in (1) above, which is a hydrocarbon wax. (3) The toner according to (1) or (2) above, wherein the weight-average molecular weight of the partially hydrogenated petroleum resin is 2000 or more and 4000 or less. (4) The toner according to any one of the above items (1) to (3), wherein the T1 / 2 of the partially hydrogenated petroleum resin is 145°C or higher. (5) A method for manufacturing the toner described in (1) above, At a minimum, the process involves mixing and melt-kneading a binder resin, a release agent, and a partially hydrogenated petroleum resin. The process involves drying the kneaded product obtained by the aforementioned melt-kneading and then crushing it. It has, The glass transition temperature of the partially hydrogenated petroleum resin is 70°C or higher and 90°C or lower. The aforementioned release agent is a hydrocarbon wax with a melting point of 85°C or higher and 90°C or lower. The glass transition temperature of the toner is 60°C or lower. Toner manufacturing method. (6) A developer containing the toner described in any one of the above items (1) to (4). (7) A toner storage unit containing the toner described in any one of the above items (1) to (4). (8) A process cartridge that is detachable from the main body of an image forming apparatus, wherein an electrostatic latent image carrier and a developing means for developing the electrostatic latent image formed on the electrostatic latent image carrier using the toner described in any one of (1) to (4) above or the developer described in (6) above are integrally supported. (9) Electrostatic latent image carrier and An electrostatic latent image forming means for forming an electrostatic latent image on the electrostatic latent image carrier, A developing means for developing the electrostatic latent image formed on the electrostatic latent image carrier using toner to form a toner image, A transfer means for transferring a toner image formed on the electrostatic latent image carrier to the surface of a recording medium, Fixing means for fixing the toner image transferred to the surface of the recording medium, Includes, An image forming apparatus in which the toner is the toner described in any one of the above items (1) to (4). (10) An electrostatic latent image formation step in which an electrostatic latent image is formed on an electrostatic latent image carrier, A developing step in which the electrostatic latent image formed on the electrostatic latent image carrier is developed using toner to form a toner image, A transfer step of transferring a toner image formed on the electrostatic latent image carrier to the surface of a recording medium, A fixing step for fixing the toner image transferred to the surface of the recording medium, Includes, An image forming method wherein the toner is the toner described in any one of the above items (1) to (4). [Explanation of Symbols]

[0100] 1. Image forming apparatus 10 Photoconductor drum 40 Developer 58 Corona Charger 80 Transfer Rollers 90 Cleaning device 110 Process Cartridges 180 Developer 210 Paper feed section 211 Paper feed cassette 212 Paper feed roller 220 Conveying section 221 Laura 222 Timing Roller 223 Paper output roller 224 Paper Output Tray 230 Image creation section 231 Photoconductor Drum 232 Charger 233 Exposure Unit 233a light source 233b Polygon Mirror 240 Transfer section 241 Drive roller 242 Driven roller 243 Intermediate transfer belt 244 Primary Transfer Roller 245 Secondary opposing roller 246 Secondary Transfer Roller 250 Fuser 251 Fixing belt 252 Pressure roller P paper [Prior art documents] [Patent Documents]

[0101] [Patent Document 1] Japanese Patent Publication No. 2011-227515

Claims

1. A toner comprising at least a binder resin, a release agent, and a partially hydrogenated petroleum resin, The aforementioned partially hydrogenated petroleum resin has a glass transition temperature of 70°C to 90°C, a weight-average molecular weight of 2000 to 4000, and a T1 / 2 of 145°C or higher. The release agent has a melting point of 85°C or higher and 90°C or lower. A toner characterized in that the glass transition temperature of the toner is 60°C or lower.

2. The toner according to claim 1, wherein the mold release agent is a hydrocarbon wax.

3. The toner according to claim 2, wherein the hydrocarbon wax is Fischer-Tropsch wax.

4. A method for manufacturing the toner described in claim 1, At a minimum, the process involves mixing and melt-kneading a binder resin, a release agent, and a partially hydrogenated petroleum resin. The process involves drying the kneaded product obtained by the aforementioned melt-kneading and then crushing it. It has, The aforementioned partially hydrogenated petroleum resin has a glass transition temperature of 70°C to 90°C, a weight-average molecular weight of 2000 to 4000, and a T1 / 2 of 145°C or higher. The aforementioned release agent is a hydrocarbon wax with a melting point of 85°C or higher and 90°C or lower. The glass transition temperature of the toner is 60°C or lower. Toner manufacturing method.

5. A developer containing the toner described in claim 1.

6. A toner storage unit containing the toner described in claim 1.

7. A process cartridge is provided, which integrally supports an electrostatic latent image carrier and a developing means for developing the electrostatic latent image formed on the electrostatic latent image carrier using the toner described in claim 1 or the developer described in claim 5, and is detachable from the main body of an image forming apparatus.

8. Electrostatic latent image carrier, An electrostatic latent image forming means for forming an electrostatic latent image on the electrostatic latent image carrier, A developing means for developing the electrostatic latent image formed on the electrostatic latent image carrier using toner to form a toner image, A transfer means for transferring a toner image formed on the electrostatic latent image carrier to the surface of a recording medium, Fixing means for fixing the toner image transferred to the surface of the recording medium, Includes, An image forming apparatus wherein the toner is the toner described in claim 1.

9. An electrostatic latent image formation step in which an electrostatic latent image is formed on an electrostatic latent image carrier, A developing step in which the electrostatic latent image formed on the electrostatic latent image carrier is developed using toner to form a toner image, A transfer step of transferring a toner image formed on the electrostatic latent image carrier to the surface of a recording medium, A fixing step for fixing the toner image transferred to the surface of the recording medium, Includes, An image forming method wherein the toner is the toner described in claim 1.

Images