JP2012255885A - Toner for electrostatic charge image, electrostatic charge image developer, toner cartridge, process cartridge, image forming device, and image forming method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a toner for an electrostatic charge image, preventing deterioration of charging characteristics while achieving low-temperature fixability.SOLUTION: The toner for an electrostatic charge image contains at least amorphous resin and crystalline polyether in which an oxygen equivalent M in a repeating unit (molecular weight of a repeating unit/the number of oxygen atoms in the repeating unit) is 100 or more and having only the repeating unit represented by the following general formula (1): [-(CH2)n-O-], wherein n is an integer of 6-12.

Description

  The present invention relates to an electrostatic charge image developing toner, an electrostatic charge image developer, a toner cartridge, a process cartridge, an image forming apparatus, and an image forming method.

  A method of visualizing image information through an electrostatic latent image such as electrophotography is currently used in various fields. In electrophotography, an electrostatic latent image formed on a photoreceptor by a charging process and an exposure process is developed with a developer containing toner, and visualized through a transfer process and a fixing process.

  For example, Patent Document 1 states that “a toner for electrophotography composed of at least a binder resin and a colorant, in which the ester concentration in the binder resin is 0.01 or more and 0.12 or less. An electrophotographic toner characterized by containing a polyester resin as a main component has been proposed.

  Patent Document 2 states that “an electrophotographic developer comprising a carrier and a toner, wherein the carrier is an electrophotographic carrier in which a coating resin layer containing a fluorine-containing resin is provided on the surface of a core material. The toner comprises at least a colorant, a crystalline polyester resin having an ester concentration of 0.06 or more and 0.12 or less, a melting point of 50 to 120 ° C., and substantially free of sulfonic acid groups. An electrophotographic developer characterized in that it is a positively charged electrophotographic toner comprising a binder resin.

  Patent Document 3 states that “the main component is a crystalline polyester resin containing at least a colorant, a divalent or higher carboxylic acid having an ester concentration and a sulfonic acid group as a copolymerization component, and a melting point of 50 to 120 ° C. And a quaternary ammonium-containing charge control agent, wherein the copolymerization amount of a divalent or higher carboxylic acid having a sulfonic acid group shows a specific relationship. "Electrophotographic toner" has been proposed.

  Patent Document 4 discloses that an electrophotographic toner having a “core layer containing crystalline polyester and two or more release agents” and a shell layer covering the core layer and containing an amorphous polymer. The melting point of the crystalline polyester is in the range of 50 to 100 ° C., the at least two types of melting points selected from the two or more types of release agents are different from each other, and the melting point is An electrophotographic toner characterized by exhibiting a specific relationship has been proposed.

  Further, Patent Document 5 states that “a toner for developing an electrostatic image comprising at least a binder resin and a colorant, wherein the binder resin contains a crystalline resin, and the crystalline resin has a specific structure. There has been proposed a toner for developing an electrostatic charge image, which is a crystalline polyester obtained by polymerizing a monomer having the above.

  Patent Document 6 states that “at least a colorant, a crystalline polyester having an ester concentration within a specific range, and an alcohol component and an acid component are synthesized. Among the alcohol components, an alkylene oxide of bisphenol A is synthesized. An amorphous polyester using an adduct in an amount of 50 mol% to 90 mol% and a linear aliphatic diol having 8 to 20 carbon atoms in the alcohol component of 10 mol% to 30 mol%. An electrophotographic toner characterized in that the content ratio (mass ratio) of the non-crystalline polyester and the crystalline polyester is a specific value has been proposed.

  Patent Document 7 proposes “a toner for electrophotography containing a polyether polyol having an ether bond in the molecule and an OH group at the molecular end and an ester obtained from a long-chain linear saturated fatty acid”. Yes.

  Patent Document 8 proposes “a magnetic latent image developing toner containing a polyether polyol resin having a hydroxyl group and an ether group having an acid value of 1 or less and a hydroxyl value of 150 or more”.

  Patent Document 9 proposes “electrostatic image developing toner using a crosslinked polyester resin having a peak top molecular weight of 3000 or more and a number average molecular weight of 2700 or more and / or a crosslinked polyether polyol resin”. ing.

  Patent Document 10 discloses that "a colored resin melt containing a polyether resin, a polyester resin, and a colorant as essential components is dispersed in water, then cooled and dried. , "Method for producing electrophotographic spherical toner".

  Further, Patent Document 11 states that “a copolymer obtained by copolymerizing at least a styrene monomer, an acrylate monomer and an active hydrogen group-containing monomer, and an isocyanate group at both ends having a polyether structure or a polyester structure. A “resin composition for toner obtained by crosslinking reaction with a prepolymer” has been proposed.

JP 2002-82485 A Japanese Patent Laid-Open No. 2004-177496 JP 2004-271575 A JP 2005-234046 A JP 2007-33828 A JP 2008-2037779 A Japanese Patent Laid-Open No. 08-227173 Japanese Patent Laid-Open No. 10-293422 JP 2002-023418 A JP 2002-229257 A JP 2009-168915 A

  An object of the present invention is to provide an electrostatic charge image developing toner that realizes low-temperature fixability and suppresses deterioration of charging characteristics.

The above problem is solved by the following means:
The invention according to claim 1
at least,
An amorphous resin;
A crystalline polyether having an oxygen atom equivalent M (the molecular weight of the repeating unit / the number of oxygen atoms in the repeating unit) of 100 or more in the repeating unit;
A toner for developing an electrostatic charge image.

The invention according to claim 2
The electrostatic image developing toner according to claim 1, wherein the crystalline polyether has only a repeating unit represented by the following general formula (1).
[— (CH ₂ ) _n —O—] General formula (1)
In said general formula (1), n represents the integer in the range of 6-12.

The invention according to claim 3
The toner for developing an electrostatic charge image according to claim 2, wherein n in the general formula (1) is an integer in the range of 8 or more and 12 or less.

The invention according to claim 4
An electrostatic charge image developer comprising at least the electrostatic charge image developing toner according to claim 1.

The invention according to claim 5
Containing the toner for developing an electrostatic charge image according to any one of claims 1 to 3,
A toner cartridge to be attached to and detached from the image forming apparatus.

The invention according to claim 6
A developing means for accommodating the electrostatic charge image developer according to claim 4 and developing the electrostatic charge image formed on the image carrier as a toner image by the electrostatic charge image developer,
A process cartridge attached to and detached from the image forming apparatus.

The invention according to claim 7 provides:
An image carrier,
Charging means for charging the image carrier;
An electrostatic charge image forming means for forming an electrostatic charge image on the surface of the charged image carrier;
Development means for containing the electrostatic image developer according to claim 4 and developing the electrostatic image formed on the image carrier as a toner image by the electrostatic image developer;
Transfer means for transferring the toner image formed on the image carrier onto a transfer target;
Fixing means for fixing the toner image transferred onto the transfer target;
An image forming apparatus comprising:

The invention according to claim 8 provides:
A charging step for charging the image carrier, an electrostatic charge image forming step for forming an electrostatic charge image on the surface of the charged image carrier, and an electrostatic image developer according to claim 4 on the image carrier. A development process for developing the electrostatic image formed on the toner image as a toner image, a transfer process for transferring the toner image formed on the image holding member onto the transfer target, and a transfer onto the transfer target. And a fixing step for fixing the toner image.

According to the first aspect of the present invention, it is possible to provide a toner for developing an electrostatic image that realizes low-temperature fixability and suppresses deterioration of charging characteristics as compared with a case where only crystalline polyester is used.
According to the second aspect of the invention, it is possible to provide a toner for developing an electrostatic charge image that is excellent in low-temperature fixability as compared with the case where a polyether other than the crystalline polyether represented by the general formula (1) is used.
According to the third aspect of the invention, there is provided an electrostatic image developing toner excellent in charging characteristics as compared with the case where a crystalline polyether represented by the general formula (1) and n is 6 or more and 7 or less is used. it can.

According to the invention of claim 4, compared to the case where the toner for developing an electrostatic charge image using only crystalline polyester is applied, the electrostatic charge image developer that realizes the low temperature fixability and suppresses the deterioration of the charging characteristics. Can provide.
In addition, according to the inventions according to claims 5, 6, 7 and 8, compared to the case where the toner for developing an electrostatic charge image using only crystalline polyester is applied, low temperature fixability is achieved and the charging characteristics of the toner are improved. It is possible to provide a toner cartridge, a process cartridge, an image forming apparatus, and an image forming method in which image defects due to deterioration are suppressed.

1 is a schematic configuration diagram illustrating an example of an image forming apparatus according to an exemplary embodiment. It is a schematic block diagram which shows an example of the process cartridge which concerns on this embodiment.

  Hereinafter, an embodiment which is an example of the present invention will be described in detail.

(Static image developing toner)
The electrostatic image developing toner according to the exemplary embodiment (hereinafter sometimes referred to as “toner”) includes an amorphous resin and a crystalline polyether.
The crystalline polyether has an oxygen atom equivalent M in the repeating unit of 100 or more.
Here, in the present embodiment, the oxygen atom equivalent M indicates a value obtained by dividing the molecular weight of the repeating unit by the number of oxygen atoms in the repeating unit.
Moreover, when a crystalline polyether is comprised by 2 or more types of repeating units, let oxygen atom equivalent M be the average value of oxygen atom equivalent M in each repeating unit.

Conventionally, in order to realize low-temperature fixability of a toner, it is known that the toner includes a crystalline polyester resin together with an amorphous resin as a binder resin.
However, when a crystalline polyester resin is added to the toner as a binder resin together with an amorphous resin, low-temperature fixability is realized, but charging characteristics may be deteriorated.

Therefore, in the toner according to the present exemplary embodiment, as a binder resin, a crystalline polyether having an oxygen atom equivalent M of 100 or more in a repeating unit is included together with an amorphous resin.
Thereby, in the toner according to the exemplary embodiment, deterioration in charging characteristics is suppressed while realizing low-temperature fixability.
The reason for this is not clear, but is presumed to be as follows.

  First, when a crystalline polyether is included in the toner, the crystalline polyether has crystallinity, and therefore has a melting temperature and a sharp melt property (a property in which the viscosity of the toner rapidly decreases before and after the fixing temperature). Therefore, it is considered that low temperature fixability is realized.

On the other hand, the “oxygen atom” constituting the crystalline polyether is considered to affect the charging characteristics of the toner.
Specifically, charging characteristics tend to deteriorate as the amount of oxygen atoms increases.
This is presumably because when the number of oxygen atoms is increased, the polarity of the toner is increased, so that the insulating property is lowered, or the polarity is increased, so that moisture is easily absorbed.

Further, the amount of oxygen atoms also affects the low temperature fixability.
Specifically, when the amount of oxygen atoms decreases, the low-temperature fixability tends to deteriorate.
This is presumably because the melting temperature of the crystalline polyether increases as the number of oxygen atoms decreases.

  Here, in the crystalline polyether, the oxygen atom equivalent M in the repeating unit of 100 or more means that the ratio of oxygen atoms to the whole crystalline polyether is small, and the oxygen atom equivalent M is within the above range. Even if crystalline polyether is included in the toner, it is considered that the influence of oxygen atoms on the charging characteristics of the toner can be suppressed.

  Therefore, it is considered that the toner according to the exemplary embodiment suppresses deterioration of charging characteristics while realizing low-temperature fixability.

  Hereinafter, the configuration of the toner according to the exemplary embodiment will be described in detail.

First, the toner will be described.
The toner according to the exemplary embodiment includes a crystalline polyether, an amorphous resin, and, if necessary, other additives such as a colorant and a release agent.

Here, the crystalline resin (crystalline polyether) refers to a resin having a clear endothermic peak rather than a stepwise endothermic amount change in thermal analysis measurement using differential scanning calorimetry (DSC). On the other hand, the amorphous resin is not a clear endothermic peak but only a step-like endothermic change in thermal analysis measurement using differential scanning calorimetry (DSC). It is a solid) and is thermoplasticized at a temperature above the glass transition temperature.
Specifically, for example, a crystalline resin (crystalline polyether) means that the half-value width of an endothermic peak when measured at a heating rate of 10 ° C./min is within 10 ° C., and is amorphous. The resin means a resin having a half width exceeding 10 ° C. or a resin in which no clear endothermic peak is observed.

The crystalline polyether will be described.
The crystalline polyether has an oxygen atom equivalent M of 100 or more, preferably 120 or more, and more preferably 140 or more.
Here, the oxygen atom equivalent M is preferably as large as possible from the viewpoint of suppressing the deterioration of the chargeability. However, from the viewpoint of compatibility with other components such as an amorphous resin, and for synthesizing a crystalline polyether. From the viewpoint of obtaining raw materials, the upper limit is desirably 300 or less.

Specific examples of the crystalline polyether include a homopolymer of a polyhydric alcohol and a copolymer of two or more polyhydric alcohols.
More specifically, as the crystalline polyether, 1) a polymer of an aliphatic polyhydric alcohol, 2) a polymer of an aliphatic polyhydric alcohol and an aromatic polyhydric alcohol, 3) And aromatic polyhydric alcohol polymers.
Here, as the crystalline polyether, from the viewpoint of imparting crystallinity, 1) a polymer of an aliphatic polyhydric alcohol and 2) an aliphatic polyhydric alcohol and an aromatic polyhydric alcohol. A polymer is good, and 1) is particularly desirable.

Examples of the aliphatic polyhydric alcohol include alkylene diol, glycerin, trimethylolpropane, pentaerythritol having an alkylene group having 6 to 20 carbon atoms (preferably 6 to 12 and more preferably 8 to 12). Etc.
Examples of the aromatic polyhydric alcohol include bisphenols such as bisphenol A and bisphenol F, hydroquinone, resorcin, catechol, pyrogallol, or their ethylene oxide, propylene oxide adduct, xylylene glycol, and the like.

The crystalline polyether is particularly preferably a crystalline polyether having only a repeating unit represented by the following general formula (1).
[— (CH ₂ ) _n —O—] General formula (1)
In said general formula (1), n shows the integer of the range of 6-20.

In particular, n in the general formula (1) preferably represents an integer in the range of 6 to 12, more preferably n represents an integer in the range of 8 to 12.
When n is in the range of 6 to 12, the oxygen atom equivalent M of the crystalline polyether tends to be in the range of 100 or more, and the ratio of oxygen atoms to the entire crystalline polyether is reduced. It becomes easy to suppress deterioration of charging property.
Further, when n is in the range of 8 or more and 12 or less, the range of oxygen atom equivalent M tends to be further increased, and the ratio of oxygen atoms to the entire crystalline polyether is reduced, so that the charging characteristics of the toner are excellent. It becomes easy.

The weight average molecular weight (Mw) of the crystalline polyether is, for example, 2000 or more and 200000 or less, desirably 3000 or more and 100000 or less, and more desirably 3000 or more and 30000 or less.
The weight average molecular weight is measured by gel permeation chromatography (GPC). The molecular weight measurement by GPC was performed with a THF solvent using a Tosoh column / TSKgel Super HM-M (15 cm) using a Tosoh GPC / HLC-8120 as a measuring device. The weight average molecular weight and the number average molecular weight are calculated using a molecular weight calibration curve prepared from a monodisperse polystyrene standard sample from this measurement result.
The same applies hereinafter.

The melting temperature of the crystalline polyether is, for example, 40 ° C. or more and 120 ° C. or less, and desirably 50 ° C. or more and 100 ° C. or less.
The melting temperature is a value obtained as the peak temperature of the endothermic peak obtained by the differential scanning calorimetry (DSC).
Crystalline polyether may show a plurality of melting peaks, but in the present embodiment, the maximum peak is regarded as the melting temperature.
The same applies hereinafter.

  Specific examples of the compound represented by the general formula (1) are shown below, but the present invention is not limited thereto.

  The content of the crystalline polyether is preferably 3% by mass or more and 50% by mass or less with respect to the toner, desirably 5% by mass or more and 45% by mass or less, and more desirably 10% by mass or more. It is as follows.

  The amorphous resin is not particularly limited, but styrenes (for example, styrene, chlorostyrene, etc.), monoolefins (for example, ethylene, propylene, butylene, isoprene, etc.), vinyl esters (for example, vinyl acetate, vinyl propionate). , Vinyl benzoate, vinyl butyrate, etc.), α-methylene aliphatic monocarboxylic acid esters (for example, methyl acrylate, ethyl acrylate, butyl acrylate, dodecyl acrylate, octyl acrylate, phenyl acrylate, methyl methacrylate, Ethyl methacrylate, butyl methacrylate, dodecyl methacrylate, etc.), vinyl ethers (eg, vinyl methyl ether, vinyl ethyl ether, vinyl butyl ether), vinyl ketones (eg, vinyl methyl ketone, vinyl hexyl ketone, vinyl isopate) Homopolymers and copolymers of Peniruketon etc.), etc., and polyester resins by copolymerization of dicarboxylic acids and diols.

In particular, typical amorphous resins include polystyrene, styrene-alkyl acrylate copolymer, styrene-alkyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-butadiene copolymer, styrene-maleic anhydride. A copolymer, a polyethylene resin, a polypropylene resin, a polyester resin, etc. are mentioned.
Typical amorphous resins also include polyurethane, epoxy resin, silicone resin, polyamide, modified rosin, paraffin wax and the like.

  The content of the amorphous resin is, for example, preferably 40% to 95% by mass, desirably 50% to 90% by mass, and more desirably 60% to 85% by mass. is there.

The colorant will be described.
The colorant is not particularly limited as long as it is a known colorant. For example, carbon black such as furnace black, channel black, acetylene black, and thermal black, inorganic pigments such as bengara, bitumen, and titanium oxide, fast yellow, disazo Yellow, pyrazolone red, chelate red, brilliant carmine, para brown and other azo pigments, copper phthalocyanine, metal-free phthalocyanine and other phthalocyanine pigments, flavantron yellow, dibromoanthrone orange, perylene red, quinacridone red and dioxazine violet Examples thereof include cyclic pigments.

  As the colorant, a surface-treated colorant may be used as necessary, or it may be used in combination with a dispersant. A plurality of colorants may be used in combination.

  The content of the colorant is desirably in the range of 1% by mass to 30% by mass with respect to the toner.

The release agent will be described.
Examples of mold release agents include hydrocarbon waxes; natural waxes such as carnauba wax, rice wax, and candelilla wax; synthetic or mineral / petroleum waxes such as montan wax; ester types such as fatty acid esters and montanic acid esters. Wax; and the like, but is not limited thereto.

  The melting temperature of the release agent is preferably 50 ° C. or higher, and more preferably 60 ° C. or higher, from the viewpoint of storage stability. Further, from the viewpoint of offset resistance, the temperature is desirably 110 ° C. or less, and more desirably 100 ° C. or less.

  The content of the release agent is preferably in the range of 2% by mass to 30% by mass with respect to the toner.

Other additives will be described.
Examples of other additives include magnetic substances, charge control agents, inorganic powders, and the like.

The toner characteristics will be described.
The toner may be a toner having a single layer structure, or may be a toner having a so-called core / shell structure including a core (core particles) and a coating layer (shell layer) covering the core. .
The core-shell toner includes, for example, a non-crystalline resin, a crystalline polyether, and a core portion containing other additives such as a colorant and a release agent as necessary, and an amorphous property. It is good to be comprised with the coating layer comprised including resin.

The volume average particle diameter of the toner is, for example, not less than 2.0 μm and not more than 10 μm, and desirably not less than 3.5 μm and not more than 7.0 μm.
In addition, as a method for measuring the volume average particle diameter of the toner, 0.5 mg or more and 50 mg or less of a measurement sample is added to 2 ml of a 5% by weight aqueous solution of a surfactant, preferably sodium alkylbenzenesulfonate, as a dispersant. The electrolyte was added to 100 ml or more and 150 ml or less. The electrolytic solution in which the measurement sample is suspended is subjected to a dispersion treatment for 1 minute with an ultrasonic disperser, and the particle size of the particle size is measured with the Coulter Multisizer II type (manufactured by Beckman-Coulter) using an aperture having an aperture diameter of 100 μm. Is a particle size distribution of particles in the range of 2.0 μm or more and 60 μm or less. The number of particles to be measured is 50,000.
For the particle size range (channel) obtained by dividing the obtained particle size distribution, the volume cumulative distribution is subtracted from the small particle size side, and the particle size that becomes 50% cumulative is defined as the volume average particle size D50v.

  The toner of the present application may include toner particles containing the above components, and may have an external additive added externally thereto.

Next, the external additive will be described.
Examples of the external additive include inorganic particles. Examples of the inorganic particles include SiO ₂ , TiO ₂ , Al ₂ O ₃ , CuO, ZnO, SnO ₂ , CeO ₂ , Fe ₂ O ₃ , MgO, BaO, and CaO. , K ₂ O, Na ₂ O, ZrO ₂ , CaO.SiO ₂ , K ₂ O. (TiO ₂ ) _n , Al ₂ O ₃ .2SiO ₂ , CaCO ₃ , MgCO ₃ , BaSO ₄ , MgSO _{4 and the} like. .

The surface of the external additive may be hydrophobized in advance. The hydrophobic treatment is performed, for example, by immersing inorganic particles in a hydrophobic treatment agent. The hydrophobizing agent is not particularly limited, and examples thereof include silane coupling agents, silicone oils, titanate coupling agents, aluminum coupling agents and the like. These may be used individually by 1 type and may use 2 or more types together.
The amount of the hydrophobizing agent is usually about 1% by mass or more and about 10% by mass with respect to 100 parts by mass of the inorganic particles, for example.

  The external additive amount is preferably 0.5% by mass or more and 2.5% by mass or less with respect to 100 parts by mass of the toner.

(Electrostatic image developer)
The electrostatic charge image developer according to the exemplary embodiment includes at least the toner according to the exemplary embodiment.
The electrostatic image developer according to this embodiment may be a one-component developer including only the toner according to this embodiment, or may be a two-component developer mixed with the toner and a carrier.

  There is no restriction | limiting in particular as a carrier, A well-known carrier is mentioned. Examples of the carrier include a resin-coated carrier, a magnetic dispersion carrier, a resin dispersion carrier, and the like.

  In the two-component developer, the mixing ratio (mass ratio) of the toner according to the exemplary embodiment and the carrier is preferably in the range of toner: carrier = 1: 100 to 30: 100, and about 3: 100 to 20: 100. The range of is more desirable.

(Image forming apparatus / image forming method)
Next, the image forming apparatus / image forming method according to the present embodiment will be described.
An image forming apparatus according to the present embodiment includes an image carrier, a charging unit that charges the image carrier, an electrostatic image forming unit that forms an electrostatic image on the surface of the charged image carrier, and an electrostatic image development. A developing means for accommodating the developer and developing the electrostatic image formed on the image carrier as a toner image by the electrostatic image developer, and transferring the toner image formed on the image carrier onto the transfer target And a fixing unit that fixes the toner image transferred onto the transfer target. The electrostatic image developer according to the present embodiment is applied as the electrostatic image developer.

  In the image forming apparatus according to the present embodiment, for example, the part including the developing unit may have a cartridge structure (process cartridge) that is detachable from the image forming apparatus. As the process cartridge, for example, A process cartridge that accommodates the electrostatic charge image developer according to the exemplary embodiment and includes a developing unit is preferably used.

  The image forming method according to the present embodiment contains a charging step for charging the image carrier, an electrostatic charge image forming step for forming an electrostatic charge image on the surface of the charged image carrier, and an electrostatic charge image developer. A developing step of developing the electrostatic image formed on the image carrier as a toner image with an electrostatic charge image developer, and a transfer step of transferring the toner image formed on the image carrier onto the transfer target; And a fixing step of fixing the toner image transferred onto the transfer medium. And as the electrostatic charge image developer, the electrostatic charge image developer according to the present embodiment is applied.

  Hereinafter, an example of the image forming apparatus according to the present embodiment will be described, but the present invention is not limited thereto. The main part shown in the figure will be described, and the description of other parts will be omitted.

  FIG. 1 is a schematic configuration diagram showing a four-tandem color image forming apparatus. The image forming apparatus shown in FIG. 1 is a first to first electrophotographic method that outputs yellow (Y), magenta (M), cyan (C), and black (K) images based on color-separated image data. Fourth image forming units 10Y, 10M, 10C, and 10K (image forming means) are provided. These image forming units (hereinafter sometimes simply referred to as “units”) 10Y, 10M, 10C, and 10K are arranged in parallel at a predetermined distance from each other in the horizontal direction. The units 10Y, 10M, 10C, and 10K may be process cartridges that are detachable from the main body of the image forming apparatus.

Above each of the units 10Y, 10M, 10C, and 10K, an intermediate transfer belt 20 as an intermediate transfer member is extended through each unit. The intermediate transfer belt 20 is provided by being wound around a driving roller 22 and a support roller 24 that are in contact with the inner surface of the intermediate transfer belt 20 that are spaced apart from each other in the left to right direction in FIG. The vehicle travels in the direction toward the unit 10K. A force is applied to the support roller 24 in a direction away from the drive roller 22 by a spring or the like (not shown), and tension is applied to the intermediate transfer belt 20 wound around the both. Further, an intermediate transfer member cleaning device 30 is provided on the side of the image carrier of the intermediate transfer belt 20 so as to face the driving roller 22.
Further, each of the developing devices (developing means) 4Y, 4M, 4C, and 4K of the units 10Y, 10M, 10C, and 10K has yellow, magenta, cyan, and black contained in the toner cartridges 8Y, 8M, 8C, and 8K. The toner including the four color toners is supplied.

  Since the first to fourth units 10Y, 10M, 10C, and 10K described above have the same configuration, here, the first image that forms the yellow image disposed on the upstream side in the intermediate transfer belt traveling direction is formed. The unit 10Y will be described as a representative. Note that the second to fourth components are denoted by reference numerals with magenta (M), cyan (C), and black (K) instead of yellow (Y) in the same parts as the first unit 10Y. Description of the units 10M, 10C, and 10K will be omitted.

The first unit 10Y includes a photoreceptor 1Y that functions as an image holding member. Around the photosensitive member 1Y, a charging roller 2Y for charging the surface of the photosensitive member 1Y to a predetermined potential, and the charged surface is exposed by a laser beam 3Y based on the color-separated image signal to form an electrostatic charge image. An exposure device (electrostatic image forming means) 3 for forming, a developing device (developing means) 4Y for supplying the charged toner to the electrostatic image and developing the electrostatic image, and transferring the developed toner image onto the intermediate transfer belt 20 A primary transfer roller 5Y (primary transfer unit) that performs the transfer and a photoconductor cleaning device (cleaning unit) 6Y that removes toner remaining on the surface of the photoconductor 1Y after the primary transfer are sequentially arranged.
The primary transfer roller 5Y is disposed inside the intermediate transfer belt 20, and is provided at a position facing the photoreceptor 1Y. Further, a bias power source (not shown) for applying a primary transfer bias is connected to each of the primary transfer rollers 5Y, 5M, 5C, and 5K. Each bias power source varies the transfer bias applied to each primary transfer roller under the control of a control unit (not shown).

Hereinafter, an operation of forming a yellow image in the first unit 10Y will be described. First, prior to the operation, the surface of the photoreceptor 1Y is charged to a potential of about −600V to −800V by the charging roller 2Y.
The photoreceptor 1Y is formed by laminating a photosensitive layer on a conductive substrate (volume resistivity at 20 ° C .: 1 × 10 ⁻⁶ Ωcm or less). This photosensitive layer usually has a high resistance (a resistance equivalent to that of a general resin), but has a property that the specific resistance of the portion irradiated with the laser beam changes when irradiated with the laser beam 3Y. Therefore, a laser beam 3Y is output to the surface of the charged photoreceptor 1Y via the exposure device 3 in accordance with yellow image data sent from a control unit (not shown). The laser beam 3Y is applied to the photosensitive layer on the surface of the photoreceptor 1Y, whereby an electrostatic charge image of a yellow print pattern is formed on the surface of the photoreceptor 1Y.

The electrostatic charge image is an image formed on the surface of the photoreceptor 1Y by charging, and the specific resistance of the irradiated portion of the photosensitive layer is lowered by the laser beam 3Y, and the charged charge on the surface of the photoreceptor 1Y flows. On the other hand, this is a so-called negative latent image formed by the charge remaining in the portion not irradiated with the laser beam 3Y.
The electrostatic charge image formed on the photoreceptor 1Y in this way is rotated to a predetermined development position as the photoreceptor 1Y travels. At this development position, the electrostatic charge image on the photoreceptor 1Y is visualized (developed image) by the developing device 4Y.

  In the developing device 4Y, for example, an electrostatic charge image developer according to the present embodiment including at least yellow toner and a carrier is accommodated. The yellow toner is triboelectrically charged by being agitated inside the developing device 4Y, and has a charge of the same polarity (negative polarity) as the charged charge on the photoreceptor 1Y, and a developer roll (developer holder). Is held on. As the surface of the photoreceptor 1Y passes through the developing device 4Y, the yellow toner is electrostatically attached to the latent image portion on the surface of the photoreceptor 1Y, and the latent image is developed with the yellow toner. . The photoreceptor 1Y on which the yellow toner image is formed continues to run at a predetermined speed, and the toner image developed on the photoreceptor 1Y is conveyed to a predetermined primary transfer position.

When the yellow toner image on the photoreceptor 1Y is conveyed to the primary transfer, a primary transfer bias is applied to the primary transfer roller 5Y, and an electrostatic force from the photoreceptor 1Y toward the primary transfer roller 5Y acts on the toner image. Then, the toner image on the photoreceptor 1Y is transferred onto the intermediate transfer belt 20. The transfer bias applied at this time is a (+) polarity opposite to the polarity (−) of the toner, and is controlled to about +10 μA by the control unit (not shown) in the first unit 10Y, for example.
On the other hand, the toner remaining on the photoreceptor 1Y is removed and collected by the cleaning device 6Y.

Further, the primary transfer bias applied to the primary transfer rollers 5M, 5C, and 5K after the second unit 10M is also controlled according to the first unit.
Thus, the intermediate transfer belt 20 onto which the yellow toner image has been transferred by the first unit 10Y is sequentially conveyed through the second to fourth units 10M, 10C, and 10K, and the toner images of the respective colors are superimposed and transferred in a multiple manner. The

  The intermediate transfer belt 20 onto which the four color toner images have been transferred in multiple layers through the first to fourth units is arranged on the image transfer surface side of the intermediate transfer belt 20, the support roller 24 in contact with the inner surface of the intermediate transfer belt 20. The secondary transfer roller (secondary transfer means) 26 is connected to a secondary transfer portion. On the other hand, the recording paper (transfer object) P is fed at a predetermined timing to the gap where the secondary transfer roller 26 and the intermediate transfer belt 20 are pressed against each other via the supply mechanism, and the secondary transfer bias is supported. Applied to the roller 24. The transfer bias applied at this time is a (−) polarity that is the same polarity as the polarity (−) of the toner, and an electrostatic force from the intermediate transfer belt 20 toward the recording paper P is applied to the toner image, so The toner image is transferred onto the recording paper P. Note that the secondary transfer bias at this time is determined according to the resistance detected by a resistance detecting means (not shown) for detecting the resistance of the secondary transfer portion, and is voltage-controlled.

  Thereafter, the recording paper P is sent to the pressure contact portions (nip portions) of the pair of fixing rolls in the fixing device (roll-type fixing unit) 28, and the toner image is fixed on the recording paper P, thereby forming a fixed image.

Examples of the transfer target to which the toner image is transferred include plain paper, OHP sheet, and the like used for electrophotographic copying machines and printers.
Examples of the transfer target include coated paper in which the surface of plain paper is coated with resin, art paper for printing, and the like.

The recording paper P on which the color image has been fixed is carried out toward the discharge unit, and a series of color image forming operations is completed.
The image forming apparatus exemplified above is configured to transfer the toner image onto the recording paper P via the intermediate transfer belt 20, but is not limited to this configuration, and the toner image is directly transferred from the photoreceptor. It may be a structure that is transferred to a recording sheet.

(Process cartridge, toner cartridge)
FIG. 2 is a schematic configuration diagram showing an embodiment of a preferred example of a process cartridge containing an electrostatic charge image developer according to this embodiment. In the process cartridge 200, a charging roller 108, a developing device 111, a photoconductor cleaning device 113, an opening 118 for exposure, and an opening 117 for static elimination exposure are combined using a mounting rail 116 together with the photoconductor 107. , And integrated. In FIG. 2, reference numeral 300 denotes a transfer target.
The process cartridge 200 is detachable from an image forming apparatus including a transfer device 112, a fixing device 115, and other components not shown.

  The process cartridge 200 shown in FIG. 2 includes a charging device 108, a developing device 111, a cleaning device 113, an opening 118 for exposure, and an opening 117 for static elimination exposure. May be combined. In the process cartridge according to the present embodiment, in addition to the photosensitive member 107, the charging device 108, the developing device 111, the cleaning device (cleaning means) 113, the opening 118 for exposure, and the opening 117 for static elimination exposure. At least one selected from the group consisting of:

  Next, the toner cartridge according to this embodiment will be described. The toner cartridge according to the present exemplary embodiment is a toner cartridge that is detachably attached to the image forming apparatus and stores at least a replenishment electrostatic image developing toner to be supplied to a developing unit provided in the image forming apparatus.

  The image forming apparatus shown in FIG. 1 is an image forming apparatus having a configuration in which the toner cartridges 8Y, 8M, 8C, and 8K are attached and detached. The developing devices 4Y, 4M, 4C, and 4K are the developing devices (colors). And a toner supply pipe (not shown). Further, when the amount of toner stored in the toner cartridge becomes low, the toner cartridge is replaced.

Hereinafter, the present invention will be described more specifically with reference to examples. However, these examples do not limit the present invention.
In the text, “part” means “part by mass” and “%” means “mass%” unless otherwise specified.

[Synthesis of crystalline polyether]
(Synthesis Example 1: Synthesis of crystalline polyether (5))
200 parts by mass of 1,10-decanediol and 4 parts by mass of 25% sulfuric acid were reacted at 200 ° C. under a nitrogen stream for 12 hours. Crystalline polyether (5) was obtained by recrystallizing twice with isopropyl alcohol after cooling.
The weight average molecular weight was 5600, and the melting temperature was 77 ° C.

(Synthesis Example 2: Synthesis of crystalline polyether (4))
A polyether (4) was obtained in the same manner as in Synthesis Example 1 except that 1,10-decanediol in Synthesis Example 1 was changed to 1,9-nonanediol.
The weight average molecular weight was 6100, and the melting temperature was 74 ° C.

(Synthesis Example 3: Synthesis of crystalline polyether (12))
110 parts by mass of 1,10-decanediol, 90 parts by mass of p-xylylene glycol, and 0.2 parts by mass of sulfamic acid were reacted at 180 ° C. for 1 hour. After cooling, it was recrystallized twice with isopropyl alcohol to obtain polyether (12).
The weight average molecular weight was 7600, and the melting temperature was 76 ° C.

(Synthesis Example 4: Synthesis of crystalline polyether (1))
A polyether (1) was obtained in the same manner as in Synthesis Example 1 except that 1,10-decanediol in Synthesis Example 1 was changed to 1,6-hexanediol.
The weight average molecular weight was 6600, and the melting temperature was 57 ° C.

(Synthesis Example 5: Synthesis of crystalline polyether (9))
A polyether (9) was obtained in the same manner as in Synthesis Example 1 except that 1,10-decanediol in Synthesis Example 1 was changed to 1,18-octadecanediol.
The weight average molecular weight was 8200, and the melting temperature was 99 ° C.

(Synthesis Example 6: Synthesis of crystalline polyether (6))
A polyether (6) was obtained in the same manner as in Synthesis Example 1 except that 1,10-decanediol in Synthesis Example 1 was changed to 1,12-dodecanediol.
The weight average molecular weight was 7000 and the melting temperature was 83 ° C.

(Synthesis Example 7: Synthesis of crystalline polyether (3))
A polyether (3) was obtained in the same manner as in Synthesis Example 1 except that 1,10-decanediol in Synthesis Example 1 was changed to 1,8-octanediol.
The weight average molecular weight was 6200, and the melting temperature was 74 ° C.

(Comparative synthesis example: synthesis of crystalline polyester resin (A))
90.1 parts by mass of 1,4-butanediol, 174.2 parts by mass of dimethyl adipate, and 0.3 parts by mass of dibutyltin oxide were reacted at 180 ° C. in a nitrogen stream for 5 hours. Thereafter, the temperature was gradually raised to 220 ° C. under reduced pressure, and the mixture was stirred for 2 hours. When it became viscous, it was air-cooled to stop the reaction and obtain a crystalline polyester resin.
The weight average molecular weight was 9800, and the melting temperature was 54 ° C.

[Example 1]
(Production of toner)
C. I. Pigment Blue B15: 3: 20 parts by mass, 75 parts by mass of ethyl acetate, 4 parts by mass of Disparon DA-703-50 (polyester acid amide amine salt, manufactured by Enomoto Kasei Co., Ltd.) and Solsperse 5000 (pigment derivative) 1 part by mass of Zeneca Co., Ltd.) was dissolved / dispersed using a sand mill to prepare a pigment dispersion.

  In addition, 30 parts by weight of paraffin wax (melting temperature 89 ° C.) and 270 parts by weight of ethyl acetate as a mold release agent were wet pulverized in a state cooled to 10 ° C. using a DCP mill to prepare a wax dispersion.

  Polyester resin comprising a condensation polymer of bisphenol A propylene oxide adduct, bisphenol A ethylene oxide adduct and terephthalic acid derivative (weight average molecular weight = 6000, glass transition temperature = 60 ° C., softening point temperature = 106 ° C., acid value 4 mgKOH / g) After stirring 136 parts by weight, 34 parts by weight of crystalline polyether (5), 34 parts by weight of pigment dispersion, and 56 parts by weight of ethyl acetate, 75 parts by weight of wax dispersion is added to the mixture, and the resulting mixture is added. The mixture was stirred (this solution was designated as solution A). On the other hand, 40 parts by mass of calcium carbonate, 124 parts by mass of a calcium carbonate dispersion dispersed in 60 parts by mass of water, 99 parts by mass of a 2% aqueous solution of Serogen BS-H (Daiichi Kogyo Seiyaku Co., Ltd.), and 157 parts by mass of water. The mixture was stirred for 5 minutes using a homogenizer (Ultra Turrax: manufactured by IKA) (this liquid was designated as B liquid).

  Further, 345 parts by mass of the B liquid and 250 parts by mass of the A liquid were stirred using a homogenizer (Ultra Turrax: manufactured by IKA) to suspend the mixed liquid. The mixture was stirred with a propeller stirrer at room temperature (25 ° C.) and normal pressure for 48 hours to remove the solvent. Next, hydrochloric acid was added to the mixed solution to remove calcium carbonate, and then the reaction mixture was washed with water, dried and classified to obtain a toner. The average particle size of the toner particles was 6 μm.

  The surface shape of the obtained toner particles was observed with a scanning electron microscope (SEM) at an acceleration voltage of 5 kV and 10,000 times.

  Next, 100 parts by mass of the toner particles were treated with silicone oil, and silicon oxide particles having an average particle diameter of 40 nm (RY50: manufactured by Nippon Aerosil Co., Ltd.) 1.3 parts by mass, silicon oxide produced by a deflagration method having an average particle diameter of 100 nm. 2 parts by mass of particles (KMP-105: classified by Shin-Etsu Chemical Co., Ltd.) and 1.5 mass of particles obtained by treating titanium oxide (MT150AW: manufactured by Teika Co., Ltd.) with an average particle size of 20 nm with 20% decyltrimethoxysilane Parts were mixed with a sample mill to prepare an electrostatic image developing toner.

  The coverage of the obtained toner was measured by XPS by measuring the signal strengths A, B, and C of only the colored particles, only the inorganic particles, and the inorganic particles of the colored particles to which the inorganic particles were adhered (Ti, Si). Each coverage was calculated | required from the formula of coverage = (CA) / (BA) * 100, and each coverage of Ti and Si was calculated | required and totaled.

[Examples 2 to 9, Comparative Examples 1 to 4]
A toner was prepared in the same manner as in Example 1 except that the kind and addition amount of the crystalline polyether were changed according to Table 1.

[Evaluation]
A developer was prepared using the toner obtained in each example, and the following evaluation was performed. The evaluation results are shown in Table 1.

The developer was prepared as follows.
100 parts of ferrite particles (manufactured by Powder Tech Co., Ltd., average particle size 50 μm) and 1.5 parts of methyl methacrylate resin (manufactured by Mitsubishi Rayon Co., Ltd., weight average molecular weight 95000) are placed in a pressure kneader together with 500 parts of toluene, and then at room temperature (25 ° C. The mixture was stirred and mixed for 15 minutes, and then heated to 70 ° C. while mixing under reduced pressure to distill off toluene, then cooled, and classified using a 105 μm sieve to obtain a resin-coated ferrite carrier.
The resin-coated ferrite carrier and the toner obtained in each example were mixed to prepare a developer (two-component electrostatic charge image developer) having a toner concentration of 7% by mass.

(Evaluation of charging characteristics)
The developed developer is applied to Fuji Xerox DocuCentre400, and image formation is performed in a summer environment (30 ° C., 88% RH) so as to form a solid portion, and further, 100 sheets are continuously formed, and the first sheet The image quality of the solid portion of the 100th image was visually evaluated according to the following criteria.
○: No unevenness or fogging in both first and 100th images.
Δ: fogging occurred in the 100th image.
×: Unevenness occurs from the first image.

(Evaluation of fixing temperature)
An image was formed on the surface of the recording paper by using DocuCentre400 manufactured by Fuji Xerox Co., Ltd., which was a modified fixing machine using the produced developer, and the low temperature fixability of the produced developer was evaluated. In the evaluation, the temperature was changed from 80 ° C. to 200 ° C. at intervals of 10 ° C., and a fixed image was produced at each fixing temperature. The degree of peeling was observed, and the lowest fixing temperature at which the image hardly peeled off was defined as the minimum fixing temperature.

  From the above results, this example obtained better results in both charging characteristics and low-temperature fixability than the comparative example.

1Y, 1M, 1C, 1K, 107 photoconductor (image carrier)
2Y, 2M, 2C, 2K, 108 Charging roller 3Y, 3M, 3C, 3K Laser beam 3 Exposure device 4Y, 4M, 4C, 4K 111 Developing device (developing means)
5Y, 5M, 5C, 5K Primary transfer rollers 6Y, 6M, 6C, 6K 113 Photoconductor cleaning device (cleaning means)
8Y, 8M, 8C, 8K Developer cartridge 10Y, 10M, 10C, 10K First to fourth units 20 Intermediate transfer belt 22 Driving roller 24 Support roller 26 Secondary transfer roller (transfer means)
28, 115 Fixing device (fixing means)
30 Intermediate transfer member cleaning device 112 Transfer device 116 Mounting rail 117 Opening portion 118 for static elimination exposure Opening portion 200 for exposure Process cartridge P, 300 Recording paper (transfer object)

Claims (8)

at least,
An amorphous resin;
A crystalline polyether having an oxygen atom equivalent M (the molecular weight of the repeating unit / the number of oxygen atoms in the repeating unit) of 100 or more in the repeating unit;
A toner for developing an electrostatic charge image. The electrostatic image developing toner according to claim 1, wherein the crystalline polyether has only a repeating unit represented by the following general formula (1).
[— (CH ₂ ) _n —O—] General formula (1)
(In the general formula (1), n represents an integer in the range of 6 to 12)   The toner for developing an electrostatic charge image according to claim 2, wherein n in the general formula (1) is an integer in the range of 8 or more and 12 or less.   An electrostatic charge image developer comprising at least the electrostatic charge image developing toner according to claim 1. Containing the toner for developing an electrostatic charge image according to any one of claims 1 to 3,
A toner cartridge to be attached to and detached from the image forming apparatus. A developing means for accommodating the electrostatic charge image developer according to claim 4 and developing the electrostatic charge image formed on the image carrier as a toner image by the electrostatic charge image developer,
A process cartridge attached to and detached from the image forming apparatus. An image carrier,
Charging means for charging the image carrier;
An electrostatic charge image forming means for forming an electrostatic charge image on the surface of the charged image carrier;
Development means for containing the electrostatic image developer according to claim 4 and developing the electrostatic image formed on the image carrier as a toner image by the electrostatic image developer;
Transfer means for transferring the toner image formed on the image carrier onto a transfer target;
Fixing means for fixing the toner image transferred onto the transfer target;
Image forming apparatus comprising A charging step for charging the image carrier;
An electrostatic charge image forming step of forming an electrostatic charge image on the surface of the charged image carrier;
A developing step of developing the electrostatic image formed on the image carrier as a toner image with the electrostatic image developer according to claim 4;
A transfer step of transferring the toner image formed on the image carrier onto a transfer target;
A fixing step of fixing the toner image transferred onto the transfer target;
An image forming method comprising: