JP2011002653A - Electrostatic latent image developing toner, electrostatic latent image developer, toner cartridge, process cartridge and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrostatic latent image developing toner which satisfies both of control of gloss unevenness on a fixed image and reduction in the quantity of heat required in image fixing.SOLUTION: The electrostatic latent image developing toner includes a binder resin including a crystalline polyester resin and a noncrystalline polyester resin and resin particles having a volume average particle diameter of 0.6-4.0 μm and a softening temperature higher than that of the noncrystalline polyester resin, and the toner has a complex elastic modulus at 80°C of ≤5×10Pa.

Description

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

  A method of visualizing image information through an electrostatic latent image, such as electrophotography, is currently widely used in various fields. In the electrophotographic method, the electrostatic latent image on the surface of the photosensitive member (latent image holding member) is developed including an electrostatic latent image developing toner (hereinafter also simply referred to as “toner”) through a charging step, an exposure step, and the like. The electrostatic latent image is visualized through a transfer step, a fixing step, and the like after developing with an agent.

In such an electrophotographic method, various toners, image forming apparatuses, image forming methods, and the like are disclosed for the purpose of controlling the gloss of the formed image surface.
Specifically, for example, Patent Document 1 discloses an image forming unit that forms and supports an unfixed toner image on a recording material, and a low-gloss image and an unfixed toner image that is supported on the recording material that passes through a fixing nip. In an image forming apparatus having a fixing device that performs heat fixing processing corresponding to both high-gloss images, it is added to the fixed toner image in an area where the fixed toner is in a soft state downstream of the fixing nip. An image forming apparatus is disclosed in which a smoothing means for smoothing by pressure contact is arranged.

In Patent Document 2, a weight average molecular weight by GPC is used in an image forming method in which a recording material is sandwiched between an endless belt and a roller and a toner image formed on the recording material is fixed by heat and pressure. A toner image is formed on a recording material using toner having a weight average molecular weight / number average molecular weight of 5 to 15 and ³ to 15% by weight of a component having a molecular weight of 1 × 10 ⁵ or more. An image forming method is disclosed in which the gloss of the fixed image is switched by means for switching the gloss of the fixed image.

  Furthermore, Patent Document 3 discloses a crosslinked type having a peak top molecular weight of 3000 or more and a number average molecular weight of 2700 or more in a chromatogram measured by gel permeation chromatography at least of a colorant, a charge control agent and tetrahydrofuran. An electrostatic charge developing toner using a polyester resin and / or a crosslinked polyether polyol resin is disclosed.

  On the other hand, in addition to the above, various toners according to purposes are disclosed. For example, in Patent Document 4, for the purpose of achieving both low-temperature fixability and heat storage properties, for electrostatic charge image development having a core particle containing a binder resin and a colorant, and a shell layer covering the core particle. In the toner, the binder resin includes at least one of a crystalline polyester resin and an amorphous resin, the shell layer includes amorphous resin fine particles, and a volume average of the amorphous resin fine particles. An electrostatic charge having a particle size of 20 to 800 nm, a glass transition temperature of 65 ° C. or more, and a content of the amorphous resin fine particles in a range of 5 to 25% by weight based on the weight of the core particles. Toner for image development

Patent Document 5 discloses a toner used in an electronic printing method in which a copy is obtained by performing development, transfer, and fixing after uniformly charging and exposing the entire surface to an electronic printing master having a fixed toner image formed on a photoreceptor. A styrene resin containing at least 30% by weight of a component having a peak molecular weight of 1 × 10 ⁶ or more as a binder resin and 50% by weight or more of a component having a peak molecular weight of 1 × 10 ^{3 to} 5 × 10 ⁴ , An electronic printing toner comprising an acrylic resin or a styrene-acrylic resin is disclosed.

  Further, in Patent Document 6, for the purpose of stabilizing the charging characteristics of the toner, resin fine particles are dispersed in an organic solvent phase in which at least a functional group-containing polyester resin is dissolved, an active hydrogen-containing compound, and a colorant. Dispersed in an aqueous medium phase, causing an elongation reaction and / or a cross-linking reaction between the functional group-containing polyester resin and the active hydrogen-containing compound, thereby forming particles from the resulting dispersion. An electrostatic charge image developing toner obtained by treating the surface of the particles with a fluorine-containing compound, wherein the toner contains at least one kind of inorganic fine particles inside the toner. Toners are disclosed.

  Further, in the fixing member used in the electrophotographic image forming apparatus, Patent Document 7 discloses a thickness of 200 μm made of a heat-resistant elastomer formed on a core metal for the purpose of preferable elasticity and excellent releasability. The heat conductive elastic layer described above, an oil resistant layer made of fluoro rubber or fluorosilicone rubber having a thickness of 3 to 200 μm formed on the elastic layer, and fibrillation formed on the oil resistant layer There is disclosed a fixing elastic roll comprising a release coating layer having a thickness of 3 to 200 μm made of a composite of a polytetrafluoroethylene and an elastomer having release properties.

JP 2003-195663 A JP 2008-58992 A Japanese Patent Laid-Open No. 2002-23418 Japanese Patent Laid-Open No. 2007-3840 JP-A-5-113690 JP 2006-145561 A Japanese Patent No. 2519112

  The object of the present invention is to achieve both suppression of increase in glossiness and suppression of gloss unevenness in a fixed image and suppression of the amount of heat required for image fixing, as compared with the case where the toner composition and complex elastic modulus are not taken into consideration. To provide an electrostatic latent image developing toner.

The above-mentioned subject is achieved by the following present invention.
That is, the invention according to claim 1
A binder resin containing a crystalline polyester resin and an amorphous polyester resin, a volume average particle size of 0.6 μm or more and 4.0 μm or less, and a softening temperature higher than the softening temperature of the amorphous polyester resin; High resin particles, and
The toner for developing an electrostatic latent image, wherein the complex elastic modulus of the toner at 80 ° C. is 5 × 10 ⁵ Pa or less.

The invention according to claim 2
An electrostatic latent image developing developer comprising the electrostatic latent image developing toner according to claim 1.

The invention according to claim 3
Toner that is removed from the image forming apparatus and supplied to at least developing means provided in the image forming apparatus is stored.
The toner is a toner cartridge which is the toner for developing an electrostatic latent image according to claim 1.

The invention according to claim 4
A process cartridge comprising developing means, wherein the developing means contains the developer for developing an electrostatic latent image according to claim 2.

The invention according to claim 5
A latent image carrier,
An electrostatic latent image forming means for forming an electrostatic latent image on the surface of the latent image holding member;
Developing means for developing the electrostatic latent image with a developer containing toner to form a toner image;
Transfer means for transferring the toner image formed on the latent image holding member onto a transfer target;
Fixing means for fixing the toner image transferred onto the transfer object,
The image forming apparatus according to claim 2, wherein the developer is an electrostatic charge image developing developer.

The invention according to claim 6
The fixing unit includes a fixing member including a base material, an elastic layer having a thickness of 0 mm to 1 mm provided on the base material, and a surface layer provided on the elastic layer. The image forming apparatus described in the above.

  According to the first aspect of the present invention, it is possible to achieve both suppression of an increase in glossiness in a fixed image, suppression of uneven glossiness, and suppression of the amount of heat required for image fixing.

  According to the second aspect of the present invention, it is possible to achieve both suppression of an increase in glossiness in a fixed image, suppression of uneven glossiness, and suppression of the amount of heat required for image fixing.

  According to the third aspect of the present invention, it is possible to achieve both suppression of glossiness increase in a fixed image, suppression of gloss unevenness, and suppression of heat amount required for image fixing.

  According to the fourth aspect of the present invention, compared with the case where the toner composition and the complex elastic modulus are not taken into consideration, the suppression of the glossiness increase in the fixed image, the suppression of the gloss unevenness, and the suppression of the heat amount required for the image fixing are compatible. Is done.

  According to the fifth aspect of the present invention, it is possible to achieve both suppression of an increase in glossiness in a fixed image, suppression of uneven glossiness, and suppression of the amount of heat required for image fixing.

  According to the sixth aspect of the present invention, in addition to the above effect, a decrease in the temperature of the fixing unit is suppressed even when the image fixing speed is increased as compared with the case where the film thickness of the elastic layer is not taken into consideration.

FIG. 3 is a cross-sectional view schematically illustrating an example of a toner according to an exemplary embodiment. (A) A cross-sectional view schematically showing a state after the toner of the present embodiment is fixed on a recording medium, and (B) a cross-sectional view schematically showing an enlarged toner portion. 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 of this embodiment.

Hereinafter, the present invention will be described in detail.
[Electrostatic latent image developing toner]
The electrostatic latent image developing toner of the present embodiment (hereinafter sometimes simply referred to as “toner”) has a binder resin containing a crystalline polyester resin and an amorphous polyester resin, and a volume average particle size of 0.1. Resin particles having a softening temperature of 6 μm or more and 4.0 μm or less and a softening temperature higher than the softening temperature of the non-crystalline polyester resin, and if necessary, other components such as a colorant and a release agent. May be included.

The toner of the present embodiment has the above-described configuration, and the complex elastic modulus of the toner is 5 × 10 ⁵ Pa or less, thereby suppressing an increase in glossiness in a fixed image, suppressing uneven glossiness, and the amount of heat required for image fixing. Is suppressed at the same time. The reason is not clear, but is presumed as follows.
In the process of fixing the toner image to the recording medium (transfer object), for example, the recording medium having the toner image formed on the surface is heated while being sandwiched between the fixing members, and the binder resin in the toner is melted. . At this time, for example, when the image forming surface of the recording medium has irregularities, the toner on the convex portion receives more pressure from the fixing member than the toner on the concave portion, so that only the toner on the convex portion is crushed and the smooth portion Occurs, and glossiness unevenness may occur due to partial increase in glossiness. In particular, in an image using black toner, when the glossiness is excessively increased in this way, the image may appear glaring.

However, in the present embodiment, for example, as illustrated in FIG. 1, the toner 50 has a configuration in which a plurality of specific resin particles 54 are dispersed in a binder resin 52. Therefore, when the toner 50 on the recording medium is sandwiched between the fixing members in the fixing step and a pressure is applied while heating, the binder resin 52 melts, but the specific resin particles 54 do not melt and keep the shape.
Therefore, as shown in FIG. 2B, irregularities corresponding to the particle size of the specific resin particles 54 are generated on the surface of the toner 50 on the recording medium P after fixing. Further, since the particle diameter of the specific resin particles 54 is in the above range, the unevenness generated on the surface of the toner 50 is larger than the visible light wavelength. That is, the visible light is irregularly reflected on the surface of the toner 50, so that the glossiness is kept low. Therefore, as shown in FIG. 2A, even when a recording medium P having an uneven surface is used, the unevenness of the surface of the toner 50 on the protrusion 56 of the recording medium P is maintained, so that the glossiness is partially It is considered that the increase in the image is suppressed, and uneven glossiness in the entire fixed image is suppressed.

Further, since the toner 50 has the above-described configuration, even if an image is fixed using a fixing member with a thin elastic layer (for example, 1 mm or less) or a fixing member without an elastic layer for the purpose of increasing the image fixing speed, An increase in degree is suppressed, and uneven gloss is suppressed.
Specifically, when a fixing member including a base material, an elastic layer, and a surface layer is used, the material used for the elastic layer is difficult to transfer heat, such as rubber. ), The elastic layer is preferably thin from the viewpoint of not lowering the temperature of the fixing portion. On the other hand, when a fixing member having an elastic layer thickness of 0 mm or more and 1 mm or less (that is, a fixing member having no elastic layer or a fixing member having a thin elastic layer) is used, the surface of the fixing member becomes hard. The pressure applied to the toner 50 becomes larger than when a member is used. At this time, when a toner having a configuration that does not include the specific resin particles 54 is used, the toner on the convex portion 56 of the recording medium P is crushed by pressure, and the glossiness is partially increased. However, since the toner 50 has the above-described configuration, the specific resin particles 54 are not easily crushed and the unevenness of the surface of the toner 50 is maintained. Therefore, it is considered that even when a fixing member having an elastic layer thickness of 0 mm or more and 1 mm or less is used, an increase in glossiness of a fixed image is suppressed and gloss unevenness is suppressed.

  Further, in the toner 50, the binder resin 52 is present together with the specific resin particles 54, and the complex elastic modulus is in the above range. Therefore, the toner composed only of the specific resin particles 54 or the complex elastic modulus is out of the above range. It is considered that the binder resin 52 melts and the image is fixed even in a state where the amount of heating at the time of fixing is smaller than that of the toner (for example, at a low temperature such as a fixing temperature of 150 ° C. or lower).

In the toner 50 of FIG. 1, one toner 50 includes a plurality of specific resin particles 54. However, the present invention is not limited thereto, and one or more specific resin particles 54 are included in one toner 50. I just need it.
In the toner 50 of FIG. 1, all the specific resin particles 54 are completely encapsulated in the binder resin 52, and there is no portion where the specific resin particles 54 are exposed to the outside of the toner 50. Alternatively, a configuration in which a part of the specific resin particles 54 is exposed to the outside of the toner 50 may be used.
Hereinafter, each component constituting the toner will be described in detail. In the following description, reference numerals may be omitted.

<Specific resin particles>
The specific resin particles are resin particles having a volume average particle diameter of 0.6 μm or more and 4.0 μm or less and a softening temperature higher than the softening temperature of the amorphous polyester resin used for the binder resin. It is not particularly limited.

The volume average particle size of the specific resin particles is 0.6 μm or more and 4.0 μm or less, preferably 0.7 μm or more and 3.5 μm or less, as described above, from the viewpoint of maintaining irregularities larger than the visible light wavelength during fixing. 5 μm or more and 3 μm or less is more preferable.
The volume average particle diameter is measured using an LS Coulter (Beckman-Coulter particle size measuring device), and the measured toner particle size distribution is divided into individual particle volumes (channels). A cumulative distribution is drawn from the smaller diameter side, and the particle size at which 50% is accumulated is defined as the volume average particle size.
In addition, when measuring the volume average particle diameter of the specific resin particles contained in the toner, the toner is put in tetrahydrofuran, dispersed in an ultrasonic disperser for 5 minutes and then filtered, and the specific resin particles obtained are filtered. A surfactant having a solid content of 2% to 5% with respect to the weight of the particles is added and redispersed in ion-exchanged water using an ultrasonic disperser, and the volume average particle diameter is measured by the above method.

As described above, the softening temperature of the specific resin particles is higher than the softening temperature of the amorphous polyester resin used for the binder resin. Specifically, the difference (T1−T2) between the softening temperature (T1) of the specific resin particles and the softening temperature (T2) of the amorphous polyester resin used for the binder resin is 30 ° C. or more and 100 ° C. or less. Is desirable, and 35 degreeC or more and 100 degrees C or less are more desirable.
In addition, the softening temperature of the specific resin particles is preferably 140 ° C. or higher, more preferably 150 ° C. or higher, from the viewpoint of suppressing partial smoothing due to heating during fixing.
As for the softening temperature, Koka-type flow tester CFT-500 (manufactured by Shimadzu Corporation) was used, the diameter of the pores of the die was 0.5 mm, the pressure load was 0.98 MPa (10 kgf / cm ² ), and the temperature was raised. It is obtained as a temperature corresponding to ½ of the height from the outflow start point to the end point when a sample of 1 cm ³ is melted out under the condition where the speed is 1 ° C./min. Hereinafter, other softening temperatures are values obtained by the same measurement.

Specific examples of the specific resin particles include cross-linked resin particles having a cross-linked structure. Examples of the specific resin particles other than the crosslinked resin particles include high softening point resin particles exhibiting a high softening temperature.
By using cross-linked resin particles, high softening point resin particles, etc. as the specific resin particles, the specific resin particles maintain their shape and maintain the irregularity of the toner surface even when pressure is applied to the toner while heating during image fixing. It is.

  Specific examples of the crosslinked resin particles include crosslinked resin particles crosslinked by ionic bonds (ionic crosslinked resin particles), crosslinked resin particles crosslinked by covalent bonds (covalently crosslinked resin particles), and the like. .

  Examples of the resin used for the crosslinked resin particles include the same resins as those used for the binder resin of general toners. Specifically, for example, ethylene resins such as polyethylene and polypropylene, Examples thereof include styrene resins such as polystyrene and α-polymethylstyrene, (meth) acrylic resins such as polymethyl methacrylate and polyacrylonitrile, polyamide resins, polycarbonate resins, polyether resins, polyester resins, and copolymer resins thereof. These resins may be used alone or in combination of two or more as required.

  Among the resins described above, styrene resins, (meth) acrylic resins, styrene- (meth) acrylic copolymer resins, and polyester resins are preferable, and polyester resins are more preferable as the resin used for the crosslinked resin particles.

Examples of the polyester resin include those obtained by condensation polymerization of polyvalent carboxylic acids and polyhydric alcohols.
Examples of polyvalent carboxylic acids include aromatic carboxylic acids such as terephthalic acid, isophthalic acid, phthalic anhydride, trimellitic anhydride, pyromellitic acid, naphthalenedicarboxylic acid; maleic anhydride, fumaric acid, succinic acid Aliphatic carboxylic acids such as alkenyl succinic anhydride and adipic acid; alicyclic carboxylic acids such as cyclohexanedicarboxylic acid; and one or more of these polyvalent carboxylic acids are used.
Among these polycarboxylic acids, terephthalic acid, fumaric acid, and alkenyl succinic anhydride are preferably used.

Examples of polyhydric alcohols include, for example, aliphatic diols such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, butanediol, hexanediol, neopentyl glycol, glycerin; cyclohexanediol, cyclohexanedimethanol, hydrogenated Examples thereof include alicyclic diols such as bisphenol A; aromatic diols such as an ethylene oxide adduct of bisphenol A and a propylene oxide adduct of bisphenol A. One or more of these polyhydric alcohols may be used.
Among these polyhydric alcohols, it is preferable to use bisphenol A ethylene oxide adduct, bisphenol A propylene oxide adduct, propylene glycol, and butanediol.

Examples of the styrene resin, (meth) acrylic resin, and styrene- (meth) acrylic copolymer resin include those obtained by polymerizing a polymerizable monomer described later by radical polymerization.
Examples of the styrene monomer include styrene, α-methylstyrene, vinylnaphthalene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene, 2-ethylstyrene, 3-ethylstyrene, 4-ethylstyrene. And alkyl-substituted styrene having an alkyl chain such as 2-chlorostyrene, 3-chlorostyrene, halogen-substituted styrene such as 4-chlorostyrene, and fluorine-substituted styrene such as 4-fluorostyrene and 2,5-difluorostyrene. . Among these, styrene and α-methylstyrene are preferable.

  (Meth) acrylic acid monomers include (meth) acrylic acid, n-methyl (meth) acrylate, n-ethyl (meth) acrylate, n-propyl (meth) acrylate, and (meth) acrylic acid. n-butyl, n-pentyl (meth) acrylate, n-hexyl (meth) acrylate, n-heptyl (meth) acrylate, n-octyl (meth) acrylate, n-decyl (meth) acrylate, ( N-dodecyl (meth) acrylate, n-lauryl (meth) acrylate, n-tetradecyl (meth) acrylate, n-hexadecyl (meth) acrylate, n-octadecyl (meth) acrylate, isopropyl (meth) acrylate , Isobutyl (meth) acrylate, t-butyl (meth) acrylate, isopentyl (meth) acrylate, amyl (meth) acrylate, (meth) Neopentyl acrylate, isohexyl (meth) acrylate, isoheptyl (meth) acrylate, isooctyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, phenyl (meth) acrylate, biphenyl (meth) acrylate, (meth ) Diphenylethyl acrylate, t-butylphenyl (meth) acrylate, terphenyl (meth) acrylate, cyclohexyl (meth) acrylate, t-butylcyclohexyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, Examples thereof include diethylaminoethyl (meth) acrylate, methoxyethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, β-carboxyethyl (meth) acrylate, (meth) acrylonitrile, (meth) acrylamide and the like. Among them, n-butyl (meth) acrylate and β-carboxyethyl (meth) acrylate are preferable.

Moreover, as a manufacturing method of covalent bond crosslinked resin particle, the method of adding a crosslinking agent at the time of superposition | polymerization etc. are mentioned, for example.
Examples of the crosslinking agent include aromatic polyvinyl compounds such as divinylbenzene and divinylnaphthalene; divinyl phthalate, divinyl isophthalate, divinyl terephthalate, divinyl homophthalate, divinyl trimesate, trivinyl trimesate, divinyl naphthalenedicarboxylate Polyvinyl esters of aromatic polycarboxylic acids such as divinyl biphenyl carboxylate; Divinyl esters of nitrogen-containing aromatic compounds such as divinyl pyridine dicarboxylate; Vinyl pyromuccinate, vinyl furan carboxylate, pyrrole-2-carboxylic acid Vinyl esters of unsaturated heterocyclic compounds such as vinyl and vinyl thiophenecarboxylate; butanediol methacrylate, hexanediol acrylate, octanediol methacrylate, decanediol acrylate (Meth) acrylic acid esters of linear polyhydric alcohols such as dodecanediol methacrylate; branches of neopentyl glycol dimethacrylate, 2-hydroxy, 1,3-diaacryloxypropane, substituted polyhydric alcohols ( (Meth) acrylic acid esters; polyethylene glycol di (meth) acrylate, polypropylene polyethylene glycol di (meth) acrylates, divinyl succinate, divinyl fumarate, vinyl maleate, divinyl maleate, divinyl diglycolate, vinyl itaconate, Divinyl itaconate, divinyl acetone dicarboxylate, divinyl glutarate, divinyl 3,3′-thiodipropionate, divinyl trans-aconitic acid, trivinyl trans-aconitic acid, divinyl adipate, pimelic acid Vinyl, divinyl suberate, azelate, divinyl sebacate, divinyl dodecanedioate divinyl, the polyvinyl esters of polycarboxylic acids such as oxalic acid divinyl and the like. A crosslinking agent may be used individually by 1 type, and may be used in combination of 2 or more type.

  As the crosslinked resin particles, commercially available crosslinked resin particles may be used as long as the volume average particle diameter is in the above range and the softening temperature satisfies the above conditions.

  On the other hand, examples of the high softening point resin particles include resin particles having a softening temperature of 140 ° C. or higher. When the above-mentioned high softening point resin particles are used as the specific resin particles, the shape of the toner is maintained even when pressure is applied while heating, due to the property that the binder resin as a matrix does not soften at the softening temperature.

  The weight average molecular weight of the high softening point resin particles is preferably 200,000 to 1,000,000, more preferably 300,000 to 1,000,000, for example, when the glass transition temperature of the high softening point resin particles is 50 ° C to 70 ° C. . On the other hand, when the glass transition temperature of the high softening point resin particles is higher than the glass transition temperature of the binder resin as a matrix, the weight average molecular weight of the high softening point resin particles may be 200,000 or less. When the weight average molecular weight of the high softening point resin particles is 200,000 or less, the glass transition temperature of the high softening point resin particles is preferably 90 ° C. or higher.

  Specific examples of the resin used for the high softening point resin particles include acrylic resin, styrene resin, styrene-acrylic copolymer resin, (α-methyl) styrene-acrylic resin, and the like.

Examples of the method for producing the high softening point resin particles include radical polymerization such as emulsion polymerization.
The high softening point resin particles may have commercially available high softening point resin particles as long as the volume average particle diameter is in the above range and the softening temperature satisfies the above conditions.

  The specific resin particles may contain components other than the resin as necessary. Examples of the components other than the resin include components other than the binder resin contained in the toner, and specific examples thereof include a colorant and a release agent described later.

  The specific resin particles are desirably insoluble in tetrahydrofuran. Here, it is confirmed as follows that the specific resin particles are insoluble in tetrahydrofuran. Specifically, 1 g of the specific resin particles is added to 10 ml of tetrahydrofuran and dispersed at 25 ° C. for 5 minutes with an ultrasonic disperser. If the weight of the remaining specific resin particles is 0.7 g or more, the specific resin particles Insoluble in tetrahydrofuran.

The content of the specific resin particles contained in the toner is preferably 20% by mass to 60% by mass, more preferably 25% by mass to 50% by mass, and further preferably 30% by mass to 40% by mass.
The specific resin particles are preferably contained in the toner in a state of being included in the binder resin.

<Binder resin>
The binder resin contains a crystalline polyester resin and an amorphous polyester resin as described above.
Hereinafter, the crystalline polyester resin and the amorphous polyester resin will be described in detail.

-Crystalline polyester resin-
As the polymerizable monomer component constituting the crystalline polyester resin, a polymerizable monomer having a linear aliphatic component rather than a polymerizable monomer having an aromatic component in order to easily form a crystal structure. Is desirable. Furthermore, in order not to impair the crystallinity, it is desirable that the constituent component derived from the polymerizable monomer is 30 mol% or more for each single species in the polymer. In the crystalline polyester resin, two or more kinds of polymerizable monomers are essential, and each essential constituent polymerizable monomer type preferably has the same structure.

The melting temperature of the crystalline polyester resin is preferably in the range of 50 to 100 ° C, more preferably in the range of 55 to 90 ° C, and still more preferably in the range of 60 to 85 ° C. When the melting temperature is lower than 50 ° C., toner storage properties such as blocking of the stored toner and storage properties of the fixed image after fixing may become difficult. Further, when the melting temperature exceeds 100 ° C., sufficient low-temperature fixability may not be obtained.
The melting temperature of the crystalline polyester resin was determined as the peak temperature of the endothermic peak obtained by the differential scanning calorimetry (DSC).

  In the present embodiment, the “crystalline polyester resin” includes not only a polymer having a 100% polyester structure as a constituent component but also a polymer (copolymer) obtained by polymerizing a component constituting a polyester and other components. means. However, in the latter case, the component other than the polyester constituting the polymer (copolymer) is 50% by mass or less.

  The crystalline polyester resin is synthesized from, for example, a polyvalent carboxylic acid component and a polyhydric alcohol component. In the present embodiment, a commercially available product may be used as the crystalline polyester resin, or a synthesized product may be used.

  Examples of the polyvalent carboxylic acid component include oxalic acid, succinic acid, glutaric acid, adipic acid, peric acid, azelaic acid, sebacic acid, 1,9-nonanedicarboxylic acid, 1,10-decanedicarboxylic acid, 1,12 -Aliphatic dicarboxylic acids such as dodecanedicarboxylic acid, 1,14-tetradecanedicarboxylic acid, 1,18-octadecanedicarboxylic acid; phthalic acid, isophthalic acid, terephthalic acid, naphthalene-2,6-dicarboxylic acid, malonic acid, mesaconic acid Aromatic dicarboxylic acids such as dibasic acids such as, and the like, and anhydrides and lower alkyl esters thereof are also included, but not limited thereto.

  Examples of the trivalent or higher carboxylic acid include 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, and the like, and anhydrides thereof. And lower alkyl esters. These may be used individually by 1 type and may use 2 or more types together.

Moreover, as a polyvalent carboxylic acid component, the dicarboxylic acid component which has a sulfonic acid group other than the said aliphatic dicarboxylic acid and aromatic dicarboxylic acid may be contained.
Furthermore, as a polyvalent carboxylic acid component, you may contain the dicarboxylic acid component which has a double bond other than the said aliphatic dicarboxylic acid and aromatic dicarboxylic acid.

  The polyhydric alcohol component is preferably an aliphatic diol, more preferably a linear aliphatic diol having a main chain portion having 7 to 20 carbon atoms. When the aliphatic diol is branched, the crystallinity of the polyester resin is lowered and the melting temperature may be lowered. Further, when the main chain portion has less than 7 carbon atoms, when polycondensation with an aromatic dicarboxylic acid, the melting temperature becomes high and fixing at low temperature may be difficult, while the main chain portion has 20 carbon atoms. Exceeding the above range makes it difficult to obtain practical materials. The number of carbon atoms in the main chain portion is more preferably 14 or less.

  Specific examples of the aliphatic diol suitably used for the synthesis of the crystalline polyester 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- Examples include, but are not limited to, tridecanediol, 1,14-tetradecanediol, 1,18-octadecanediol, 1,14-eicosandecanediol, and the like. Among these, considering availability, 1,8-octanediol, 1,9-nonanediol, and 1,10-decanediol are desirable.

  Examples of the trivalent or higher alcohol include glycerin, trimethylolethane, trimethylolpropane, pentaerythritol and the like. These may be used individually by 1 type and may use 2 or more types together.

  Among the polyhydric alcohol components, the content of the aliphatic diol is preferably 80 mol% or more, and more preferably 90% or more. When the content of the aliphatic diol is less than 80 mol%, the crystallinity of the polyester resin is lowered and the melting temperature is lowered, so that toner blocking resistance, image storage stability, and low-temperature fixability may be deteriorated. .

  If necessary, a polycarboxylic acid or a polyhydric alcohol may be added at the final stage of the synthesis for the purpose of adjusting the acid value or the hydroxyl value. Examples of polycarboxylic acids include aromatic carboxylic acids such as terephthalic acid, isophthalic acid, phthalic anhydride, trimellitic anhydride, pyromellitic acid, naphthalenedicarboxylic acid; maleic anhydride, fumaric acid, succinic acid, alkenyl Aliphatic carboxylic acids such as succinic anhydride and adipic acid; and alicyclic carboxylic acids such as cyclohexanedicarboxylic acid.

The crystalline polyester resin is produced at a polymerization temperature of 180 to 230 ° C., and the reaction system is depressurized as necessary to carry out the reaction while removing water and alcohol generated during the condensation.
When the polymerizable monomer is not dissolved or compatible at the reaction temperature, a solvent having a high boiling point may be added as a solubilizer and dissolved. In the polycondensation reaction, the dissolution auxiliary solvent is distilled off. If there is a polymerizable monomer having poor compatibility in the copolymerization reaction, the polymerizable monomer having poor compatibility and the polymerizable monomer and the acid or alcohol to be polycondensed are condensed in advance. And then polycondensation with the main component.

  Examples of the catalyst used in the production of the polyester resin include alkali metal compounds such as sodium and lithium; alkaline earth metal compounds such as magnesium and calcium; zinc, manganese, antimony, titanium, tin, zirconium, and germanium. Metal compounds such as: phosphorous acid compounds; phosphoric acid compounds; and amine compounds.

  The acid value of the crystalline polyester resin (the number of mg of KOH required to neutralize 1 g of resin) is desirably in the range of 3.0 to 30.0 mgKOH / g, and 6.0 to 25.0 mgKOH / g. It is more desirable to be in the range of 8.0 to 20.0 mgKOH / g.

  When the acid value is lower than 3.0 mgKOH / g, the dispersibility in water is lowered, and thus it may be difficult to prepare emulsified particles by a wet manufacturing method. Further, since stability as emulsified particles during aggregation is significantly reduced, it may be difficult to produce an efficient toner. On the other hand, when the acid value exceeds 30.0 mgKOH / g, the hygroscopicity as a toner increases and the toner may be easily affected by the environment.

  The weight average molecular weight (Mw) of the crystalline polyester resin is preferably 6,000 to 35,000. When the weight average molecular weight (Mw) is less than 6,000, the toner permeates the surface of a recording medium such as paper during fixing, and uneven fixing occurs, or the strength against bending resistance of the fixed image decreases. There is a case. On the other hand, when the weight average molecular weight (Mw) exceeds 35,000, the viscosity at the time of melting becomes too high, and the temperature for reaching a viscosity suitable for fixing may be increased, resulting in the deterioration of the low-temperature fixability. There is a case.

  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 is calculated from the measurement result using a molecular weight calibration curve prepared with a monodisperse polystyrene standard sample.

  The content of the crystalline polyester resin in the toner is preferably in the range of 3 to 40% by mass, more preferably in the range of 4 to 35% by mass, and still more preferably in the range of 5 to 30% by mass. When the content of the crystalline polyester resin is less than 3% by mass, sufficient low-temperature fixability may not be obtained. When the content is more than 40% by mass, sufficient toner strength and fixed image strength cannot be obtained. There is a case where an adverse effect on the charging property is also caused.

  The crystalline resin containing the above crystalline polyester resin is mainly composed of a crystalline polyester resin synthesized from an aliphatic polymerizable monomer (hereinafter sometimes referred to as “crystalline aliphatic polyester resin”). 50 mass% or more) is desirable. Furthermore, in this case, the constituent ratio of the aliphatic polymerizable monomer constituting the crystalline aliphatic polyester resin is preferably 60 mol% or more, and more preferably 90 mol% or more. As the aliphatic polymerizable monomer, the above-mentioned aliphatic diols and dicarboxylic acids are preferably used.

-Amorphous polyester resin-
Examples of desirably used amorphous polyester resins include those obtained by polycondensation of polyvalent carboxylic acids and polyhydric alcohols.
Examples of the polyvalent carboxylic acid are the same as those exemplified for the above-described crystalline polyester resin.

  Examples of the polyhydric alcohol in the amorphous polyester resin are the same as those exemplified for the crystalline polyester resin.

The amorphous polyester resin preferably has a glass transition temperature (Tg) in the range of 50 to 80 ° C. If Tg is lower than 50 ° C., problems may occur in terms of toner storage stability and fixed image storage stability. If it is higher than 80 ° C., it may not be fixed at a lower temperature than in the past.
The Tg of the amorphous polyester resin is more preferably 50 to 65 ° C.

  In addition, manufacture of the said amorphous polyester resin is performed according to the case of the said crystalline polyester resin.

  The softening temperature (flow tester 1/2 drop temperature) of the binder resin is preferably 90 ° C. or higher and 140 ° C. or lower, more preferably 100 ° C. or higher and 135 ° C. or lower, and more preferably 100 ° C. or higher, from the viewpoint of improving the image fixability. 120 degrees C or less is more preferable.

  The binder resin is preferably soluble in tetrahydrofuran. Here, “soluble in tetrahydrofuran” means that 1 g of binder resin is added to 10 ml of tetrahydrofuran and dissolved in tetrohydrofuran when dispersed in an ultrasonic disperser at 25 ° C. for 5 minutes.

<Colorant>
The toner may contain a colorant as necessary. The colorant may be a dye or a pigment, but a pigment is desirable from the viewpoint of light resistance and water resistance.
Desirable colorants include, for example, carbon black, aniline black, aniline blue, calcoil blue, chrome yellow, ultramarine blue, DuPont oil red, quinoline yellow, methylene blue chloride, phthalocyanine blue, malachite green oxalate, lamp black, Rose Bengal, Quinacridone, Benzicine Yellow, C.I. I. Pigment red 48: 1, C.I. I. Pigment red 57: 1, C.I. I. Pigment red 122, C.I. I. Pigment red 185, C.I. I. Pigment red 238, C.I. I. Pigment yellow 12, C.I. I. Pigment yellow 17, C.I. I. Pigment yellow 180, C.I. I. Pigment yellow 97, C.I. I. Pigment yellow 74, C.I. I. Pigment blue 15: 1, C.I. I. And known pigments such as CI Pigment Blue 15: 3.

  The content of the colorant in the toner is preferably in the range of 1 to 30 parts by mass with respect to 100 parts by mass of the binder resin. It is also effective to use a surface-treated colorant or a pigment dispersant as necessary. By selecting the type of the colorant, yellow toner, magenta toner, cyan toner, black toner and the like can be obtained.

<Release agent>
The toner may contain a release agent as necessary. Examples of the release agent include paraffin wax such as low molecular weight polypropylene and low molecular weight polyethylene; silicone resin; rosins; rice wax; carnauba wax;
The melting temperature of the release agent is preferably 50 ° C. to 100 ° C., more preferably 60 ° C. to 95 ° C.
The content of the release agent in the toner is preferably 0.5 to 15% by mass, and more preferably 1.0 to 12% by mass. If the content of the release agent is less than 0.5% by mass, peeling failure may occur particularly in oilless fixing. When the content of the release agent is more than 15% by mass, the image quality and the reliability of image formation may be deteriorated, for example, the fluidity of the toner is deteriorated.

<Other additives>
In addition to the above components, the toner may contain various components such as an internal additive, a charge control agent, inorganic powder (inorganic particles), and organic particles as necessary.
Examples of the internal additive include metals such as ferrite, magnetite, reduced iron, cobalt, nickel, and manganese, alloys, and magnetic materials such as compounds containing these metals.
Examples of the charge control agent include quaternary ammonium salt compounds, nigrosine compounds, dyes composed of complexes of aluminum, iron, chromium, and triphenylmethane pigments.

  The inorganic particles are added for various purposes, but may be added for adjusting the viscoelasticity of the toner. By adjusting the viscoelasticity, image glossiness and penetration into paper are adjusted. As the inorganic particles, known inorganic particles such as silica particles, titanium oxide particles, alumina particles, cerium oxide particles, or those obtained by hydrophobizing the surface thereof may be used alone or in combination of two or more. From the viewpoint of not impairing transparency such as color developability and OHP permeability, silica particles having a refractive index smaller than that of the binder resin are preferably used. Further, the silica particles may be subjected to various surface treatments, and for example, those subjected to surface treatment with a silane coupling agent, a titanium coupling agent, a silicone oil or the like are preferably used.

Specific examples of the inorganic particles and organic particles, which are external additives externally added to the toner surface, include the following.
Examples of inorganic particles include silica, alumina, titanium oxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate, zinc oxide, silica sand, clay, mica, wollastonite, diatomaceous earth, cerium chloride, Examples include Bengala, chromium oxide, cerium oxide, antimony trioxide, magnesium oxide, zirconium oxide, silicon carbide, and silicon nitride. Among these, silica particles and titanium oxide particles are desirable, and particles that have been subjected to hydrophobic treatment are particularly desirable.

Inorganic particles are generally used for the purpose of improving fluidity. The primary particle size of the inorganic particles is desirably in the range of 1 to 200 nm, and the addition amount is desirably in the range of 0.01 to 20 parts by mass with respect to 100 parts by mass of the toner.
Organic particles are generally used for the purpose of improving cleaning properties and transfer properties. Specifically, for example, fluorine resin powders such as polyvinylidene fluoride and polytetrafluoroethylene, fatty acid metal salts such as zinc stearate and calcium stearate. , Polystyrene, polymethyl methacrylate and the like.

<Toner characteristics>
As described above, the complex elastic modulus of the toner at 80 ° C. is 5 × 10 ⁵ Pa or less, preferably 1 × 10 ⁴ Pa or more and 4 × 10 ⁵ Pa or less, from the viewpoint of suppressing the amount of heat required for image fixing. X10 ⁴ Pa or more and 3 × 10 ⁵ Pa or less is more preferable.
The complex elastic modulus of the toner is obtained as follows. Specifically, a temperature rise measurement is performed using a rheometer (manufactured by Rheometric Scientific: ARES rheometer) under the condition of a frequency of 1 Hz using a parallel plate. More specifically, a sample is set at a temperature of 120 ° C. to 140 ° C., cooled to room temperature (25 ° C.), and then heated at a rate of temperature increase of 1 ° C./min. The storage elastic modulus, loss elastic modulus, complex elastic modulus, and tan δ at the time of temperature increase are measured for each ° C. The complex elastic modulus of the toner was measured with the upper limit of strain being 20%.

  The tan δ value of the toner at 100 ° C. is preferably 0.4 or more and 1.3 or less, more preferably 0.5 or more and 1.1 or less, and more preferably 0.5 or more and 1.0 or less. Further preferred. Further, it is more preferable that the tan δ value of the toner at 120 ° C. is in the same range and is smaller than tan δ at 100 ° C., that is, it is difficult for viscous flow to occur with respect to temperature rise. The tan δ value of the toner depends on the particle size and content of the specific resin particles. When the particle size of the specific resin particles is in an appropriate range, the tan δ value is small, and the content of the specific resin particles in the toner is small. As the value increases, the tan δ value decreases. When the tan δ value of the toner is in the above range, the balance between the volume average particle diameter and the content of the specific resin particles is good, so that the amount of heat necessary for fixing, the glossiness of the fixed image is increased, and the glossiness of the fixed image is It is suppressed.

The volume average particle size of the toner is desirably in the range of 4 to 9 μm, more desirably in the range of 4.5 to 8.5 μm, and even more desirably in the range of 5 to 8 μm. When the volume average particle size is smaller than 4 μm, the toner fluidity is lowered, the chargeability of each particle is likely to be lowered, and the charge distribution is widened, so that fogging on the background and toner spillage from the developing device are likely to occur. . On the other hand, if it is smaller than 4 μm, the cleaning property may be extremely difficult. If the volume average particle size is larger than 9 μm, the resolution decreases, so that sufficient image quality cannot be obtained, and it may be difficult to satisfy recent high image quality requirements.
The measurement of the volume average particle diameter will be described later.

The toner preferably has a spherical shape with a shape factor SF1 in the range of 110 to 140. When the shape is spherical in this range, transfer efficiency and image density are improved, and a high-quality image is formed.
The shape factor SF1 is more preferably in the range of 110 to 130.

Here, the shape factor SF1 is obtained by the following equation (12).
SF1 = (ML ² / A) × (π / 4) × 100 (12)
In the above formula (12), ML represents the absolute maximum length of the toner, and A represents the projected area of the toner.

  The SF1 is quantified mainly by analyzing a microscope image or a scanning electron microscope (SEM) image with an image analyzer, and is calculated as follows, for example. That is, an optical microscope image of higher alcohol particles dispersed on the surface of the slide glass is taken into a Luzex image analyzer by a video camera, the maximum length and projected area of 100 particles are obtained, calculated by the above equation (12), and the average Obtained by determining the value.

<Toner production method>
Next, a toner manufacturing method will be described.
The method for producing the toner is not particularly limited, and for example, a specific resin particle dispersion adjusting step in which specific resin particles are dispersed, a resin particle dispersion adjusting step in which a resin particle dispersion in which binder resin particles are dispersed, and A mixed solution adjusting step of adjusting the mixed solution by mixing the specific resin particle dispersion and the resin particle dispersion, an agglomerated particle forming step of forming the agglomerated particles including the specific resin particles and the resin particles, and the agglomerated particles as the resin Preferable is an emulsion polymerization agglomeration method having a fusing and coalescence step of fusing and coalescing by heating to a temperature equal to or higher than the glass transition temperature of the particles (or the melting temperature of the crystalline resin).
In addition, the toner may be produced by other wet production methods. In addition to the above emulsion polymerization aggregation method, a component used as necessary, such as a release agent and a colorant, is replaced with a binder resin such as a crystalline resin. Suspension polymerization method for suspending together with a polymerizable monomer to be formed and polymerizing the polymerizable monomer, a compound having an ionic dissociation group, a binder resin such as a crystalline resin, and a toner constituent material such as a release agent May be dissolved in an organic solvent and dispersed in an aqueous solvent in a suspended state, and then a dissolution suspension method in which the organic solvent is removed may be used.

  When the emulsion polymerization aggregation method is used, other dispersions such as an inorganic particle dispersion and a resin particle dispersion in which an amorphous resin is dispersed may be added. In particular, when an inorganic particle dispersion having a hydrophobic surface is added, the dispersibility of the release agent and crystalline resin inside the toner is controlled by the degree of hydrophobicity.

Hereinafter, a toner production method by an emulsion polymerization aggregation method will be described in more detail as a specific example.
When the toner is prepared by the emulsion polymerization aggregation method, as described above, each dispersion liquid adjustment step (that is, specific resin particle dispersion liquid adjustment step, resin particle dispersion liquid adjustment step, etc.) and the aggregate particle formation step are integrated. Agglomerated particles having a core / shell structure in which resin particles are attached to the surface of the agglomerated particles (core particles) formed through the agglomerated particle forming step. An adhesion process to be formed may be provided.

In the specific resin particle dispersion adjusting step, the specific resin particle dispersion in which only the specific resin particles are dispersed in the solvent may be adjusted in advance, but the specific resin is prepared after adjusting another dispersion (for example, the resin particle dispersion). Particles may be added and dispersed to adjust the specific resin particle dispersion.
Further, in the present embodiment, in order to disperse the specific resin particles in the binder resin, it is desirable that the resin dispersed particles are uniformly mixed at the stage of the aggregation process.
Hereinafter, each step will be described in detail.

-Each dispersion adjustment process-
As the specific resin particle dispersion, the specific resin particle dispersion obtained at the time of producing the specific resin particles may be used as it is, or the specific resin particle dispersion obtained by dispersing the specific resin particles in a solvent (for example, water). It may be used.

Examples of the adjustment of the resin particle dispersion in which the binder resin particles are dispersed include a method of emulsifying the obtained resin by mechanical shearing force and a method of using a phase inversion emulsification method.
As an example of a method for preparing a resin particle dispersion by a phase inversion emulsification method, for example, a binder resin is dissolved in a mixed liquid of an organic solvent (good solvent) and a water-soluble solvent (water-soluble poor solvent), and necessary Depending on the condition, a neutralizing agent (for example, ammonia) or a dispersion stabilizer is added, and a water-soluble solvent (for example, water) is added dropwise with stirring to obtain emulsified particles, and then the solvent in the resin particle dispersion is added. Removal is performed to obtain an emulsion (resin particle dispersion). The order of adding the neutralizing agent and the dispersion stabilizer may be changed.
Examples of the method of emulsifying with a mechanical shear force include a method in which a shear force is applied to a solution obtained by mixing an aqueous medium and a binder resin with a disperser. At that time, it is desirable to form particles by heating to lower the viscosity of the resin component. A dispersant may be used for stabilizing the dispersed resin particles.

As the size of the resin particles, the average particle size (volume average particle size) is preferably in the range of 0.08 to 0.8 μm, more preferably 0.09 to 0.6 μm, and 0.10 to 0.5 μm. More desirable.
The volume average particle diameter of the resin particles is measured using a laser diffraction particle size distribution measuring device (LA-700: manufactured by Horiba, Ltd.). As a measuring method, the sample in the state of dispersion is adjusted so as to have a solid content of 2 g, and ion exchange water is added thereto to make 40 ml. This is put into the cell, waits for 2 minutes, and is measured when the concentration in the cell becomes stable. The obtained volume average particle diameter for each channel is accumulated from the smaller volume average particle diameter, and the place where the accumulation reaches 50% is defined as the volume average particle diameter. The volume average particle diameters of the release agent particles and the colorant particles are also measured by the same method.

  The colorant particle dispersion is prepared by a known method, for example, a dispersion adjustment method using a media type dispersing machine such as a rotary shear type homogenizer, a ball mill, a sand mill, or an attritor, or a high pressure opposed collision type dispersing machine. It is done. Moreover, you may use the ionic surfactant which has polarity at the time of dispersion | distribution.

  The release agent particle dispersion is, for example, dispersed in water together with a polymer electrolyte such as an ionic surfactant, polymer acid or polymer base, heated above the melting temperature, and subjected to strong shearing. A release agent particle dispersion liquid containing release agent particles is prepared by adjusting the particles by forming them with a homogenizer or a pressure discharge type dispersing machine.

-Mixed solution adjustment process-
In the mixed solution adjustment step, each of the dispersions adjusted in each of the above dispersion adjustment steps (specific resin particle dispersion, resin particle dispersion, and if necessary, colorant particle dispersion, release agent particle dispersion, etc. To prepare a mixed solution.

-Aggregated particle formation process-
In the aggregated particle forming step, the mixed solution (raw material dispersion) is heated to form aggregated particles in which the particles in the mixed solution are aggregated. The heating is preferably performed in a temperature range lower than the melting temperature of the crystalline resin (temperature lower by 20 ° C. to 10 ° C. than the melting temperature). Aggregated particles are formed by adding an aggregating agent at a temperature of 20 ° C. to 30 ° C. under stirring with a rotary shearing homogenizer to make the pH of the raw material dispersion acidic.
The flocculant used in the agglomerated particle forming step can take a valence of 2 or more in addition to a surfactant having a reverse polarity to the surfactant used as a dispersant added to the raw material dispersion, that is, an inorganic metal salt. A metal complex containing a metal element is preferably used. In particular, the use of a metal complex is particularly preferable because the amount of the surfactant used is reduced and the charging characteristics are improved.

It is preferable to add an inorganic particle dispersion of the inorganic metal salt to cause aggregation. This effectively acts on the molecular chain terminal of the binder resin and contributes to the formation of a crosslinked structure.
The inorganic particle dispersion may be prepared using a known method, for example, a ball mill, a sand mill, an ultrasonic disperser rotary shearing homogenizer or the like, and the dispersion average particle diameter of the inorganic particles may be in the range of 100 nm to 500 nm. preferable.

  In the aggregated particle forming step, the inorganic particle dispersion may be added stepwise or continuously. These methods are effective in dispersing the metal ion component in the inorganic particle dispersion from the toner surface to the inside. When adding stepwise, it is particularly preferable to add the dispersion at a slow rate of about 0.1 g / m or less when adding continuously in three steps or more.

  The amount of the inorganic particle dispersion added varies depending on the type of metal required and the degree of formation of the crosslinked structure, but is in the range of 0.5 to 10 parts by mass with respect to 100 parts by mass of the binder resin component. Preferably, the range is 1 part by mass or more and 5 parts by mass or less.

In the agglomerated particle forming step, toner particles are prepared by adjusting the type and amount of inorganic metal salt or metal complex containing a metal element capable of taking a valence of 2 or more in a range that does not affect the formation of agglomerated particles. You may control content of the metal element which can take the valence more than bivalence contained in it.
Note that aluminum sulfate, polyaluminum chloride, and calcium chloride are preferably used among the flocculants listed above from the viewpoint that it is easier to achieve both low-temperature fixability and a gloss unevenness suppressing effect.

-Adhesion process-
After the aggregated particle forming step, an attaching step may be performed if necessary. In the attaching step, a coating layer is formed by attaching resin particles to the surface of the aggregated particles formed through the above-described aggregated particle forming step. As a result, a toner having a core / shell structure including a core layer and a shell layer (coating layer) covering the core layer is obtained.

  The coating layer is formed by additionally adding a resin particle dispersion containing amorphous resin particles to the dispersion in which the aggregated particles (core particles) are formed in the aggregated particle formation step. When an amorphous resin is used in addition to the crystalline resin in the aggregated particle forming step, the amorphous resin used in the adhesion step is the same as or different from that used in the aggregated particle forming step. Also good.

  The main purpose of the adhesion process is to suppress the exposure of the release agent and crystalline resin contained in the core layer to the toner surface, and to supplement the strength of the toner particles that is insufficient with the core layer alone.

-Fusion / unification process-
In the agglomerated particle forming step, or the fusion and coalescence step performed after the agglomerated particle forming step and the attaching step, the pH of the suspension containing the agglomerated particles formed through these steps is set to a desired range. Thus, after the progress of aggregation is stopped, the aggregated particles are fused by heating.

The pH is adjusted by adding an acid and / or alkali. Although an acid is not specifically limited, The aqueous solution which contains inorganic acids, such as hydrochloric acid, nitric acid, and a sulfuric acid, in 0.1 to 50 mass% is preferable. The alkali is not particularly limited, but an aqueous solution containing an alkali metal hydroxide such as sodium hydroxide or potassium hydroxide in the range of 0.1% by mass to 50% by mass is preferable.
In the pH adjustment, if a local pH change occurs, local aggregated particles themselves may be destroyed or local excessive aggregation may be caused, and the shape distribution may be deteriorated. In particular, the larger the scale, the greater the amount of acid and / or alkali. For example, when the number of acid and alkali injection sites is one, the concentration of acid and alkali at the input site increases as the scale increases if the treatment is performed for the same time. Therefore, it is desirable to adjust the pH by, for example, taking time or using a plurality of input points so that a local pH change does not occur.

  After performing the composition control described above, the aggregated particles are heated and fused. In the fusion, the aggregated particles are fused by heating at a temperature of 10 to 30 ° C. or higher from the melting temperature of the crystalline resin (or the glass transition temperature of the amorphous resin when an amorphous resin is used). .

The cross-linking reaction may be performed with other components during the heating at the time of fusion or after the fusion is completed. Further, a crosslinking reaction may be performed together with the fusion. When the crosslinking reaction is performed, the above-described crosslinking agent and polymerization initiator are used in the production of the toner.
The polymerization initiator may be preliminarily mixed with the dispersion at the stage of preparing the raw material dispersion, or may be incorporated into the aggregated particles in the aggregated particle forming step. Furthermore, it may be introduced after the fusion / unification step or after the fusion / unification step. In the case of introducing after the aggregated particle forming step, the adhering step, the fusing / merging step, or the fusing / merging step, a solution in which the polymerization initiator is dissolved or emulsified may be added to the dispersion. These polymerization initiators may be added with known crosslinking agents, chain transfer agents, polymerization inhibitors and the like for the purpose of controlling the degree of polymerization.

-Cleaning, drying process, etc.-
After completing the coalescence and coalescence process of the aggregated particles, the desired toner particles (toner particles) are obtained through a washing process, a solid-liquid separation process, and a drying process. Replacement cleaning is desirable. Moreover, although there is no restriction | limiting in particular in a solid-liquid separation process, From the point of productivity, suction filtration, pressure filtration, etc. are suitable. Further, the drying process is not particularly limited, but freeze drying, flash jet drying, fluidized drying, vibration fluidized drying and the like are preferably used from the viewpoint of productivity.
In addition, the various external additives described above may be added to the dried toner particles (toner particles) as necessary.

[Electrostatic latent image developer]
The toner for developing an electrostatic latent image of this embodiment is used as it is as a one-component developer or as a two-component developer. When used as a two-component developer, it is used by mixing with a carrier.

  The carrier that can be used in the two-component developer is not particularly limited, and a known carrier is used. Examples thereof include magnetic metals such as iron oxide, nickel and cobalt, magnetic oxides such as ferrite and magnetite, resin-coated carriers having a resin coating layer on the surface of the core material, and magnetic dispersion carriers. Further, a resin-dispersed carrier in which a conductive material or the like is dispersed in a matrix resin may be used.

  Coating resins and matrix resins used for carriers include polyethylene, polypropylene, polystyrene, polyvinyl acetate, polyvinyl alcohol, polyvinyl butyral, polyvinyl chloride, polyvinyl ether, polyvinyl ketone, vinyl chloride-vinyl acetate copolymer, styrene-acrylic. Examples include, but are not limited to, an acid copolymer, a straight silicone resin containing an organosiloxane bond or a modified product thereof, a fluororesin, a polyester, a polycarbonate, a phenol resin, and an epoxy resin.

  Examples of the conductive material include metals such as gold, silver and copper, carbon black, titanium oxide, zinc oxide, barium sulfate, aluminum borate, potassium titanate, tin oxide, and carbon black, but are not limited thereto. It is not something.

  Examples of the core material of the carrier include magnetic metals such as iron, nickel, and cobalt, magnetic oxides such as ferrite and magnetite, and glass beads. However, in order to use the carrier for the magnetic brush method, it is a magnetic material. It is desirable. The volume average particle size of the core material of the carrier is generally in the range of 10 to 500 μm, and preferably in the range of 30 to 100 μm.

  In order to coat the surface of the core material of the carrier with a resin, there may be mentioned a method of coating with a coating layer forming solution prepared by dissolving the coating resin and, if necessary, various additives in an appropriate solvent. The solvent is not particularly limited, and may be selected in consideration of the coating resin to be used, coating suitability, and the like.

  Specific resin coating methods include an immersion method in which the carrier core material is immersed in the coating layer forming solution, a spray method in which the coating layer forming solution is sprayed onto the surface of the carrier core material, and the carrier core material is fluidized air. A fluidized bed method in which the coating layer forming solution is sprayed in a state of being suspended by the above, a kneader coater method in which the carrier core material and the coating layer forming solution are mixed in a kneader coater, and the solvent is removed.

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

[Toner cartridge, image forming apparatus, and process cartridge]
Next, a toner cartridge according to the present embodiment (hereinafter sometimes simply referred to as “cartridge”) will be described. The cartridge stores the toner of the present embodiment. Further, the cartridge may be structured to be detachable from the image forming apparatus.

The image forming apparatus according to the present embodiment develops a latent image holding member, an electrostatic latent image forming unit that forms an electrostatic latent image on the surface of the latent image holding member, and the electrostatic latent image as a toner image using a developer. A developing unit; a transfer unit that transfers the toner image formed on the latent image holding member onto the transfer member; and a fixing unit that fixes the toner image transferred onto the transfer member. The electrostatic latent image developer of this embodiment is used as the agent.
The image forming apparatus is not particularly limited as long as it includes at least the latent image holding member, the electrostatic latent image forming unit, the developing unit, the transfer unit, and the fixing unit as described above. , Charging means, cleaning means, static elimination means and the like may be included.

  In the present embodiment, the fixing member includes a fixing member including a base material, an elastic layer having a thickness of 0 mm to 1 mm provided on the base material, and a surface layer provided on the elastic layer. It is preferable to use a fixing unit. That is, it is preferable to use a fixing member that does not include an elastic layer or a fixing member that includes an elastic layer of 1 mm or less. By using such a fixing member, the heat conduction of the fixing member is good, so that even if the image fixing speed is increased, the temperature drop of the fixing portion is suppressed, and the image is fixed satisfactorily. That is, in the present embodiment, since the toner is used as the toner, even if the elastic layer of the fixing member is thin, an increase in glossiness in the formed image is suppressed, and uneven glossiness is suppressed. Therefore, even in the case of continuous printing with an increased image fixing speed, the thin elastic layer provides excellent thermal conductivity and suppresses a decrease in temperature on the fixing surface.

The thickness of the elastic layer is preferably closer to 0 mm from the viewpoint of increasing the image fixing speed. However, from the viewpoint of achieving both an increase in the image fixing speed, suppression of increase in glossiness, and suppression of uneven gloss, 0 mm. It is preferably 1 mm or less, more preferably 0.1 mm or more and 0.7 mm or less, and further preferably 0.2 mm or more and 0.3 mm or less.
The fixing member may be a roll-shaped fixing member (fixing roll) or a belt-shaped fixing member (fixing belt). The fixing member may include other layers (for example, an adhesive layer that bonds the base material and the elastic layer).

  The process cartridge in the present embodiment is provided with developing means and contains the developer of the described embodiment, and, as necessary, an electrostatic latent image holding member, charging means, cleaning means, and static elimination means. Other members such as these may be included.

  Hereinafter, the cartridge, the image forming apparatus, and the process cartridge according to the present embodiment will be specifically described with reference to the drawings.

  FIG. 3 is a cross-sectional view schematically showing a basic configuration of an image forming apparatus according to a preferred embodiment. The image forming apparatus shown in FIG. 3 includes a cartridge.

3 includes an electrostatic latent image holding body 12, a charging unit 14, an electrostatic latent image forming unit 16, a developing unit 18, a transfer unit 20, a cleaning unit 22, a charge eliminating unit 24, a fixing unit 26, A cartridge 28 is provided.
The toner stored in the developing unit 18 and the cartridge 28 is the toner of this embodiment.

  The image forming apparatus shown in FIG. 3 is an image forming apparatus to which a cartridge 28 is attached and detached, and the cartridge 28 is connected to the developing unit 18 through a toner supply pipe 30. Therefore, when forming an image, the toner stored in the cartridge 28 is supplied to the developing unit 18 through the toner supply tube 30. Further, when the amount of toner stored in the cartridge 28 is low, the cartridge 28 may be replaced.

  Around the electrostatic latent image holding body 12, charging means 14 for charging the surface of the electrostatic latent image holding body 12 in order along the rotational direction (arrow A direction) of the electrostatic latent image holding body 12, and image information Accordingly, an electrostatic latent image forming means 16 for forming an electrostatic latent image on the surface of the electrostatic latent image holding body 12, a developing means 18 for supplying toner of the present embodiment to the formed electrostatic latent image, an electrostatic latent image Drum-shaped transfer means 20 that contacts the surface of the holding body 12 and rotates following the direction of the arrow B as the electrostatic latent image holding body 12 rotates in the direction of arrow A, and a cleaning device that contacts the surface of the electrostatic latent image holding body 12 22. A neutralizing means 24 for neutralizing the surface of the electrostatic latent image holding body 12 is disposed.

  A recording medium 44 transported in the direction of arrow C by a transport unit (not shown) is inserted between the electrostatic latent image holder 12 and the transfer unit 20 from the opposite side to the direction of arrow C. A fixing unit 26 incorporating a heating source (not shown) is disposed on the electrostatic latent image holding body 12 in the direction of arrow C, and the fixing unit 26 is provided with a contact portion 32. The recording medium 44 that has passed between the electrostatic latent image holding member 12 and the transfer means 20 is inserted through the contact portion 32 in the direction of arrow C.

As the electrostatic latent image holding member 12, for example, a photosensitive member or a dielectric recording member is used.
As the photoreceptor, for example, a photoreceptor having a single layer structure or a photoreceptor having a multilayer structure is used. As the material of the photoconductor, an inorganic photoconductor such as selenium or amorphous silicon, an organic photoconductor, or the like can be considered.

  Examples of the charging means 14 include a contact charging device using a conductive or semiconductive roller, brush, film, rubber blade, or the like, a non-contact charging device such as corotron charging or scorotron charging using corona discharge, and the like. Well-known means are used.

As the electrostatic latent image forming means 16, any conventionally known means for forming a signal capable of forming a toner image at a desired position on the surface of the recording medium may be used in addition to the exposure means.
As the exposure means, conventionally known exposure means such as a combination of a semiconductor laser and a scanning device, a laser scanning writing device constituted by an optical system, or an LED head are used.

  Specifically, as the transfer unit 20, for example, a conductive or semiconductive roller, a brush, a film, a rubber blade, or the like to which a voltage is applied is used. The back surface of the recording medium 44 is corona charged by means for creating an electric field and transferring a toner image formed by charged toner particles, a corotron charger using a corona discharge, a scorotron charger, etc. Conventionally known means such as means for transferring a toner image formed of particles is used.

  Further, as the transfer unit 20, a secondary transfer unit may be used. That is, although not shown, the secondary transfer unit is a unit that transfers the toner image to the intermediate transfer member and then secondary-transfers the toner image from the intermediate transfer member to the recording medium 44.

  Examples of the cleaning unit 22 include a cleaning blade and a cleaning brush. In the present embodiment, a blade cleaning unit using a cleaning blade 42 is employed as the cleaning unit 22.

  Examples of the static eliminating unit 24 include a tungsten lamp and an LED.

Examples of the fixing unit 26 include a heat fixing unit that includes a heating roll incorporating a halogen heater and a pressure roll that contacts the heating roll by applying pressure, and fixes the toner image by heating and pressing. .
Examples of the heating roll and the pressure roll include those formed by laminating a heat-resistant elastic layer and a release layer around a metal core (cylindrical core).
Examples of the material of the core include aluminum (for example, A-5052 material), metals such as SUS, iron, and copper, alloys, ceramics, and FRM (fiber reinforced metal). Examples of the core include a cylindrical body having an outer diameter of 25 mm, a thickness of 0.5 mm, and a length of 360 mm.
Examples of the material for the elastic layer include silicone rubber and fluororubber.
Examples of the material for the release layer include fluorine rubber, silicone rubber, fluorine resin, and silicone resin. Examples of the thickness of the release layer include 5 to 50 μm.

  The recording medium 44 is not particularly limited, and conventionally known media such as plain paper and glossy paper are used. A recording medium having a base material and an image receiving layer formed on the base material may be used.

  Next, image formation using the image forming apparatus 10 will be described. First, as the electrostatic latent image holding body 12 rotates in the direction of arrow A, the surface of the electrostatic latent image holding body 12 is charged by the charging unit 14, and the electrostatic latent image holding body 12 surface is charged with the electrostatic latent image. An electrostatic latent image corresponding to the image information is formed by the image forming means 16, and the developing means 18 is formed on the surface of the electrostatic latent image holding body 12 on which the electrostatic latent image is formed according to the color information of the electrostatic latent image. A toner image is formed by supplying the developer of this embodiment.

  Next, the toner image formed on the surface of the electrostatic latent image holding body 12 is brought into contact with the electrostatic latent image holding body 12 and the transfer unit 20 as the electrostatic latent image holding body 12 rotates in the arrow A direction. Move to the department. At this time, the recording medium 44 is inserted through the contact portion in the direction of the arrow C by a paper transport roll (not shown), and the electrostatic latent image is transferred by the voltage applied between the electrostatic latent image holder 12 and the transfer means 20. The toner image formed on the surface of the image carrier 12 is transferred to the surface of the recording medium 44 at the contact portion.

  After the toner image is transferred to the recording medium 44 by the transfer unit 20, the toner remaining on the surface of the electrostatic latent image holding body 12 is removed by the cleaning blade 42 of the cleaning unit 22, and the charge is removed by the charge removing unit 24. .

  The recording medium 44 having the toner image transferred onto the surface in this way is conveyed to the contact portion 32 of the fixing unit 26 and is contacted by a built-in heating source (not shown) when passing through the contact portion 32. The surface of the section 32 is heated by the heated fixing means 26. At this time, an image is formed by fixing the toner image on the surface of the recording medium 44.

  FIG. 4 is a cross-sectional view schematically showing a basic configuration of an image forming apparatus according to another preferred embodiment. The image forming apparatus shown in FIG. 4 includes a process cartridge.

  An image forming apparatus 200 shown in FIG. 4 includes a process cartridge 210, an electrostatic latent image forming unit 216, a transfer unit 220, and a fixing unit 226 that are arranged to be attached to and detached from an image forming apparatus main body (not shown). And.

  The process cartridge 210 has an electrostatic latent image holding body 212 in a casing 211 provided with an opening 211A for forming an electrostatic latent image, and a charging unit 214, a developing unit 218, and a cleaning unit 222 around the electrostatic latent image holding member 212. These are combined and integrated by mounting rails (not shown). Note that the process cartridge 210 is not limited to this, and may include the developing unit 218 and at least one selected from the group consisting of the electrostatic latent image holding member 212, the charging unit 214, and the cleaning unit 222.

  On the other hand, the electrostatic latent image forming unit 216 is disposed at a position where an electrostatic latent image is formed on the electrostatic latent image holding body 212 from the opening 211A of the casing 211 of the process cartridge 210. The transfer unit 220 is disposed at a position facing the electrostatic latent image holder 212.

  The individual details of the electrostatic latent image holding member 212, the charging unit 214, the electrostatic latent image forming unit 216, the developing unit 218, the transfer unit 220, the cleaning unit 222, the fixing unit 226, and the recording medium 250 are illustrated in FIG. The same as the electrostatic latent image holding body 12, the charging unit 14, the electrostatic latent image forming unit 16, the developing unit 18, the transfer unit 20, the cleaning unit 22, the fixing unit 26, and the recording medium 44 in the image forming apparatus 10 of FIG. .

  The image formation using the image forming apparatus 200 of FIG. 4 is the same as the image formation using the image forming apparatus 10 of FIG.

EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated concretely, this invention is not limited only to the Example shown below.
In the examples, “parts” and “%” mean “parts by mass” and “% by mass” unless otherwise specified.

[Measurement methods for various characteristics]
First, methods for measuring physical properties of developers and the like used in Examples and Comparative Examples will be described.

<Measurement of softening temperature>
The softening temperature was measured using a Koka flow tester CFT-500 (manufactured by Shimadzu Corporation), the diameter of the die pores was 0.5 mm, the pressure load was 0.98 MPa (10 kg / cm ² ), and the temperature was raised. The temperature was determined as a temperature corresponding to ½ of the height from the outflow start point to the end point when a 1 cm ³ sample was melted out under the condition where the speed was 1 ° C./min.

<Measurement of melting temperature and glass transition temperature>
The melting temperature and glass transition temperature were measured by using “DSC-20” (manufactured by Seiko Denshi Kogyo Co., Ltd.) and heating 10 mg of the sample at a constant rate of temperature increase (10 ° C./min).
For the measurement of the melting temperature of the crystalline resin, a differential scanning calorimeter (DSC) was used, and JIS K-7121 when measurement was performed at a temperature rising rate of 10 ° C. per minute from room temperature (25 ° C.) to 150 ° C .: It was determined as the melting peak temperature of the input compensated differential scanning calorimetry shown in 87.
The crystalline resin sometimes shows a plurality of melting peaks, but the maximum peak was regarded as the melting temperature.
Moreover, the glass transition temperature of an amorphous resin is the value measured by the method (DSC method) prescribed | regulated to ASTMD3418-82.

<Measurement of weight average molecular weight Mw and number average molecular weight Mn>
The molecular weight distribution of the toner was obtained under the following conditions. GPC uses “HLC-8120GPC, SC-8020 (manufactured by Tosoh Corp.)”, column uses “TSKgel, SuperHM-H (Tosoh Corp. 6.0 mmID × 15 cm)”, two eluents THF (tetrahydrofuran) was used. As experimental conditions, the sample concentration was 0.5%, and the flow rate was 0.6 ml / min. The experiment was conducted using a sample injection amount of 10 μl, a measurement temperature of 40 ° C., and an IR detector. In addition, the calibration curve is “polystyrene standard sample TSK standard” manufactured by Tosoh Corporation: “A-500”, “F-1”, “F-10”, “F-80”, “F-380”, “ It was prepared from 10 samples of “A-2500”, “F-4”, “F-40”, “F-128”, and “F-700”.

<Measurement of average particle diameter of toner>
A Coulter Multisizer II type (manufactured by Beckman Coulter, Inc.) was used for measuring the volume average particle diameter of the toner particles (toner). In this case, measurement was performed using a 50 μm aperture. The particle diameter of the measured particle represents a volume average particle diameter unless otherwise specified.
As a measurement method, 1.0 mg of a measurement sample is added to 2 ml of a 5% aqueous solution of a surfactant, specifically, sodium alkylbenzenesulfonate as a dispersant. This was added to 100 ml of the electrolytic solution to prepare an electrolytic solution in which the sample was suspended.
The electrolytic solution in which the sample is suspended is subjected to a dispersion treatment for 1 minute with an ultrasonic disperser, and the particle size distribution of 1 to 30 μm particles is measured using the Coulter counter TA-II with an aperture diameter of 50 μm. An average distribution and a number average distribution are obtained. The number of particles to be measured was 50,000.

<Measurement of average particle size of specific resin particles>
LS Coulter (manufactured by Beckman Coulter, Inc.) was used for measuring the volume average particle diameter of the specific resin particles. With respect to the measured particle size distribution (channel), a cumulative distribution is drawn from the smaller diameter side with respect to the divided particle size range (channel), and the particle size at which 50% is accumulated is defined as the volume average particle size.
In addition, when measuring the volume average particle diameter of the specific resin particles contained in the toner, the toner is put in tetrahydrofuran, dispersed in an ultrasonic disperser for 5 minutes and then filtered, and the specific resin particles obtained are filtered. A surfactant having a solid content of 2 to 5% or more based on the weight of the particles was added and redispersed in ion-exchanged water using an ultrasonic disperser, and the volume average particle diameter was measured by the above method.

<Measurement of complex elastic modulus and tan δ value of toner at 80 ° C.>
The complex elastic modulus of the toner is obtained as follows. Specifically, a temperature rise measurement is performed using a rheometer (manufactured by Rheometric Scientific: ARES rheometer) under the condition of a frequency of 1 Hz using a parallel plate. More specifically, a sample is set at a temperature of 120 ° C. to 140 ° C., cooled to room temperature (25 ° C.), and then heated at a rate of temperature increase of 1 ° C./min. The storage elastic modulus, loss elastic modulus, complex elastic modulus, and tan δ at the time of temperature increase were measured for each ° C.

<Measurement of Volume Average Particle Size and Content of Specific Resin Particles Contained in Toner>
The toner is put in tetrahydrofuran, dispersed for 5 minutes with an ultrasonic disperser, and then filtered to obtain specific resin particles. The content of the specific resin particles in the toner was calculated from the mass of the obtained specific resin particles, and the volume average particle size of the specific resin particles was measured by the above method using the obtained specific resin particles.

<Method for measuring acid value of resin>
2 g of a sample was weighed and dissolved in 160 ml of acetone-toluene, or a sample with insufficient solubility was heated and dissolved, and then measured by the potentiometric titration method of JIS K0070-1992.

[Production of crosslinked resin particles / ultra high molecular weight resin particles]
<Adjustment of dispersion>
-Preparation of Amorphous Polyester Resin Particle Dispersion 1-
・ Bisphenol A propylene oxide 2 molar adduct 310 parts ・ 116 parts of terephthalic acid ・ 12 parts of fumaric acid ・ 54 parts of dodecenyl succinic acid ・ 0.05 parts of Ti (OBu) 4

  After the above raw materials were put into a heat-dried three-necked flask, the air in the container was depressurized by a depressurization operation, and was further brought into an inert atmosphere with nitrogen gas, and refluxed at 180 ° C. for 5 hours with mechanical stirring. Thereafter, the temperature was gradually raised to 230 ° C. while distilling off the water produced in the reaction system by vacuum distillation. Further, the dehydration condensation reaction was continued at 240 ° C. for 3 hours, and when it became viscous, the molecular weight was confirmed by GPC. When the weight average molecular weight reached 18000, vacuum distillation was stopped and amorphous polyester resin 1 was obtained. Obtained. Amorphous polyester resin 1 was amorphous and had a glass transition temperature of 59 ° C., a softening temperature of 110 ° C., and an acid value of 13 mgKOH / g. In the present invention, “Bu” represents “butyl”.

  Next, 100 parts of this amorphous polyester resin 1, 50 parts of ethyl acetate, 25 parts of isopropyl alcohol, and 5 parts of 10% aqueous ammonia solution were placed in a separable flask and mixed and dissolved sufficiently. While heating and stirring at 40 ° C., ion-exchanged water was added dropwise at a liquid feed rate of 8 g / min using a liquid feed pump. After the liquid became cloudy, the liquid feeding speed was increased to 25 g / min to cause phase inversion, and dropping was stopped when the liquid feeding amount reached 135 parts. Thereafter, the solvent was removed under reduced pressure to obtain an amorphous polyester resin particle dispersion 1. The obtained polyester resin particles had a volume average particle size of 132 nm and the polyester resin particles had a solid content concentration of 32.96%.

-Preparation of crystalline polyester resin particle dispersion-
In a heat-dried three-necked flask, 230 parts of 1,10-dodecanedioic acid, 160 parts of 1,9-nonanediol, and 0.2 part of dibutyltin oxide as a catalyst were added, and then the air in the three-necked flask was removed by depressurization. The reaction was allowed to proceed under an inert atmosphere by replacing with nitrogen at 180 ° C. for 5 hours by mechanical stirring and refluxing. During the reaction, water produced in the reaction system was distilled off. Thereafter, the temperature was gradually raised to 230 ° C. under reduced pressure, and when the mixture became viscous after stirring for 2 hours, the molecular weight was confirmed by GPC. When the weight average molecular weight reached 29000, the distillation under reduced pressure was stopped and the crystals were crystallized. A functional polyester resin was obtained. The crystalline polyester resin had a melting temperature of 73 ° C., a softening temperature of 75 ° C., and an acid value of 12 mgKOH / g.

  Next, 100 parts of this crystalline polyester resin, 35 parts of ethyl acetate, and 35 parts of isopropyl alcohol are placed in a separable flask and thoroughly mixed and dissolved at 75 ° C. Then, 5.5 parts of a 10% aqueous ammonia solution is added dropwise. did. The heating temperature is lowered to 60 ° C., and ion-exchanged water is added dropwise with stirring using a liquid feed pump at a liquid feed speed of 6 g / min. After the liquid becomes cloudy, the liquid feed speed is increased to 25 g / min. When the amount reached 400 parts, dropping of ion-exchanged water was stopped. Thereafter, the solvent was removed under reduced pressure to obtain a crystalline polyester resin particle dispersion. The obtained crystalline polyester resin particles had a volume average particle size of 136 nm and the polyester resin particles had a solid content concentration of 24.43%.

-Preparation of colorant particle dispersion-
・ Carbon black (Degussa, NIPex35) 100 parts ・ Anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen R) 15 parts ・ Ion-exchanged water 900 parts A colorant particle dispersion liquid in which carbon black was dispersed by dispersing for 1 hour using Iser (manufactured by Sugino Machine Co., Ltd., HJP30006) was prepared. The average particle diameter of the colorant particles in the colorant particle dispersion was 0.13 μm, and the colorant particle concentration was 21.36%.

-Preparation of release agent particle dispersion-
-FNP92 (Nippon Seiki Co., Ltd.) 50 parts-Anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd .: Neogen RK) 5 parts-Ion-exchanged water 200 parts A mold release agent having an average particle size of 0.24 μm and a melting temperature of 92 ° C. after being dispersed using IKA (Ultra Turrax T50) and then dispersed with a Manton Gorin high-pressure homogenizer (Gorin). Particles were dispersed to prepare a release agent particle dispersion having a release agent concentration of 31.12%.

<Preparation of crosslinked resin particle 1>
Non-crystalline polyester resin particle dispersion 1 437.973 parts Release agent particle dispersion 59.287 parts Colorant particle dispersion 60.225 parts Crystalline polyester resin particle dispersion 56.783 parts Ion exchange 480 parts of water In a polymerization kettle equipped with a pH meter, stirring blades, and thermometer, the above raw materials were put, and 100 parts of 1% aqueous solution of aluminum sulfate was added as a flocculant while applying a shear force at 6000 rpm with Ultraturrax (manufactured by IKA Japan). It was dripped.

Next, the raw material mixture was stirred at 550 to 650 rpm while being heated to 30 ° C. with a mantle heater. After stirring for 60 minutes, it was confirmed that the primary particle size was stably formed using Multisizer II type (aperture diameter: 50 μm, manufactured by Beckman-Coulter), and then 0.5 ° C / The temperature rose in minutes.
The agglomerated particle diameter is confirmed from time to time using Multisizer II type. When the volume average particle diameter of the aggregated particles becomes 3.2 μm, in order to stop the growth of the aggregated particles (adherent particles), 1M sodium hydroxide aqueous solution is added in order, and the pH of the raw material mixture is controlled to 8.0. did. Subsequently, in order to fuse the aggregated particles, the temperature was raised to 95 ° C. at a temperature raising rate of 1 ° C./min. After confirming that the aggregated particles were fused with an optical microscope, the mixture was cooled to obtain crosslinked resin particles 1 having a volume average particle diameter of 3.2 μm. The crosslinked resin particles 1 had a softening temperature higher than the softening temperature of the resin used as a raw material by ionic crosslinking of aluminum ions and resin carboxylic acid, and the softening temperature Tm was 150 ° C.

<Preparation of crosslinked resin particles 2>
A crosslinked resin particle 2 was produced in the same manner as the crosslinked resin particle 1 except that the growth of the aggregated particles (adhered particles) was stopped at 2.8 μm. Table 1 shows the volume average particle diameter and softening temperature of the crosslinked resin particles.

<Preparation of crosslinked resin particles 3>
Instead of the crosslinked resin particles 1, commercially available crosslinked acrylic resin particles (trade name: MX-300, manufactured by Soken Chemical Co., Ltd.) were used as the crosslinked resin particles 3. Table 1 shows the volume average particle diameter and softening temperature of the crosslinked resin particles.

<Preparation of crosslinked resin particles 4>
Instead of the crosslinked resin particles 1, commercially available crosslinked acrylic resin particles (trade name: MX-150, manufactured by Soken Chemical Co., Ltd.) were used as the crosslinked resin particles 4. Table 1 shows the volume average particle diameter and softening temperature of the crosslinked resin particles.

<Preparation of crosslinked resin particles 5>
Instead of the crosslinked resin particles 1, commercially available styrene divinylbenzene resin particles (trade name: SX8742-08, manufactured by JSR Corporation) were used as the crosslinked resin particles 5. Table 1 shows the volume average particle diameter and softening temperature of the crosslinked resin particles.

<Preparation of crosslinked resin particles 6>
A crosslinked resin particle 6 was produced in the same manner as the crosslinked resin particle 1 except that the growth of the aggregated particles (adhered particles) was stopped at 4.0 μm. Table 1 shows the volume average particle diameter and softening temperature of the crosslinked resin particles.

<Preparation of crosslinked resin particles 7>
Instead of the crosslinked resin particles 1, commercially available styrene divinylbenzene resin particles (trade name: SX8742-05, manufactured by JSR Corporation) were used as the crosslinked resin particles 7. Table 1 shows the volume average particle diameter and softening temperature of the crosslinked resin particles.

<Preparation of crosslinkable resin particles 8>
In advance, 325 parts of styrene, 75 parts of n-butyl acrylate, 9 parts of β-carboxyethyl acrylate, 1.5 parts of 1,10-decanediol diacrylate were mixed, and 2.7 parts of dodecanethiol was added to the monomer. A mixture was prepared. Next, 4 parts of an anionic surfactant (Dowfax manufactured by Dow Chemical Co., Ltd.) is mixed with 550 parts of ion-exchanged water, and 6 parts of ammonium persulfate is added and dissolved while stirring and mixing slowly for 10 minutes. A dispersion emulsion of a surfactant and ion exchange water was prepared. Subsequently, 50 parts of the dispersion emulsion of the anionic surfactant and ion-exchanged water was put into a monomer mixture prepared in advance, and after sufficiently replacing nitrogen in the reaction vessel system, 70 ° C. The polymerization reaction was continued for 5 hours to prepare a polystyrene-acrylic resin particle dispersion. The obtained polystyrene-acrylic resin was an amorphous resin, the weight average molecular weight (Mw) was 30000, and the glass transition temperature was 51.5 ° C. The solid concentration of the particle dispersion is 42%, and the center diameter of the particles in the resin dispersion is 0.195 μm.

・ Polystyrene-acrylic resin particle dispersion 376.629 parts ・ Releasing agent particle dispersion 59.287 parts ・ Colorant particle dispersion 60.225 parts ・ Ion-exchanged water 480 parts A pH meter, stirring blade, and thermometer The raw material was put into the polymerization kettle, and 100 parts of 1% aqueous solution of aluminum sulfate was added dropwise as a flocculant while applying a shearing force at 6000 rpm with Ultraturrax (manufactured by IKA Japan) to obtain crosslinked resin particles 8. The crosslinked resin particles 8 had a softening temperature higher than the softening temperature of the resin used as a raw material by ionic crosslinking of aluminum ions and resin carboxylic acid, and the softening temperature Tm was 155 ° C.

<High softening point resin particles 9>
Instead of the crosslinked resin particles 1, commercially available acrylic resin particles (trade name: MP1451, manufactured by Soken Chemical) were used as the high softening point resin particles 9.
Table 1 shows the volume average particle diameter and softening temperature of the high softening point resin particles 9.

<Preparation of crosslinked resin particle 10>
A crosslinked resin particle 10 was produced in the same manner as the crosslinked resin particle 1 except that the growth of aggregated particles (adhered particles) was stopped at 4.0 μm. Table 1 shows the volume average particle diameter and the softening temperature of the crosslinked resin particles.

<Preparation of crosslinked resin particles 11>
Instead of the crosslinked resin particles 1, commercially available crosslinked styrene resin particles (trade name: SX500, manufactured by Soken Chemical Co., Ltd.) were used as the crosslinked resin particles 11.
Table 1 shows the volume average particle diameter and softening temperature of the crosslinked resin particles 11.

[Production of toner]
<Preparation of dispersion>
-Preparation of Amorphous Polyester Resin Particle Dispersion 2-
-310 parts of bisphenol A propylene oxide 2 mol adduct-116 parts of terephthalic acid-12 parts of fumaric acid-54 parts of dodecenyl succinic acid-0.05 part of Ti (OBu) 4 After the above raw materials were put into a heat-dried three-necked flask, The air in the container was depressurized by a depressurization operation, and was further brought into an inert atmosphere with nitrogen gas, and refluxed at 180 ° C. for 5 hours with mechanical stirring. Thereafter, the temperature was gradually raised to 230 ° C. while distilling off the water produced in the reaction system by vacuum distillation. Further, the dehydration condensation reaction was continued at 240 ° C. for 5 hours, and when it became a viscous state, the molecular weight was confirmed by GPC. Obtained. Amorphous polyester resin 2 was amorphous and had a glass transition temperature of 61 ° C., a softening temperature of 115 ° C., and an acid value of 13 mgKOH / g. In the present invention, “Bu” represents “butyl”.

  Next, 100 parts of this amorphous polyester resin 2, 50 parts of ethyl acetate, 25 parts of isopropyl alcohol, and 5 parts of 10% aqueous ammonia solution were placed in a separable flask and mixed and dissolved sufficiently. While heating and stirring at 40 ° C., ion-exchanged water was added dropwise at a liquid feed rate of 8 g / min using a liquid feed pump. After the liquid became cloudy, the liquid feeding speed was increased to 25 g / min to cause phase inversion, and dropping was stopped when the liquid feeding amount reached 135 parts. Thereafter, the solvent was removed under reduced pressure to obtain amorphous polyester resin particle dispersion 2. The obtained polyester resin particles had a volume average particle size of 132 nm and the polyester resin particles had a solid content concentration of 35.71%.

<Preparation of Toner 1>
-Crosslinked resin particles 1 (for 30 wt% of crosslinked particles in toner) 60 parts-Amorphous polyester resin particle dispersion 2 113.13 parts-Release agent particle dispersion 59.287 parts-Colorant particle dispersion 60.225 Part / Crystalline polyester resin particle dispersion 56.783 part / Ion-exchanged water 781 part The above raw materials were placed in a polymerization kettle equipped with a pH meter, stirring blades, and thermometer, and sheared at 6000 rpm with Ultraturrax (manufactured by IKA Japan). While applying force, 100 parts of a 1% aqueous solution of aluminum sulfate was added dropwise as a flocculant to prepare a raw material mixture.

  Next, the raw material mixture was stirred at 550 to 650 rpm while being heated to 30 ° C. with a mantle heater. After stirring for 60 minutes, it was confirmed that the primary particle diameter was formed using Multisizer II type (aperture diameter: 50 μm, manufactured by Beckman-Coulter), and then grown at 0.5 ° C./minute to grow aggregated particles. The temperature rose. The agglomerated particle diameter is confirmed from time to time using Multisizer II type. When the volume average particle diameter of the aggregated particles becomes 6.5 μm, 156.82 parts of non-crystalline polyester resin particle dispersion 2 is added to coat the aggregated particles and stop the growth of the aggregated particles (adherent particles). For this purpose, 16.7 parts of an aqueous EDTA solution (Kyles 40 manufactured by Kires Corporation diluted to 12% by mass with ion-exchanged water) and 1M aqueous sodium hydroxide solution were added in order, and the pH of the raw material mixture was controlled at 8.0. did. Subsequently, in order to fuse the aggregated particles, the temperature was raised to 95 ° C. at a temperature raising rate of 1 ° C./min. After confirming that the aggregated particles were fused with an optical microscope, the toner was cooled to obtain a toner 1 having a volume average particle diameter of 6.5 μm. The volume average particle diameter of the toner, the complex elastic modulus at 80 ° C., the tan δ value at 100 ° C. and 120 ° C., and the volume average particle diameter and content of the specific resin particles contained in the toner are measured, and the results are shown in Table 2. .

<Production of Toner 2 to Toner 13 and 16 to 19>
In the same manner as in the toner 1 except that the type and addition amount of the used crosslinked resin particles or high softening point resin particles (hereinafter sometimes referred to as “particles”) are as shown in Table 2, the toner 2 to the toner 13, 16 to 19 were produced.
For toner 2 to toner 12 and toner 16 to toner 17, the content of the crystalline polyester resin is 8 as the resin component amount (the total mass of the crystalline polyester resin, the amorphous polyester resin, and the particles). It was set as mass%. Further, the content of the crystalline polyester resin in the toner 13, the toner 18, and the toner 19 is 4% by mass, 2% by mass, and 0% by mass, respectively, of the resin component amount.
The volume average particle diameter of the toner, the complex elastic modulus at 80 ° C., the tan δ value at 100 ° C. and 120 ° C., and the volume average particle diameter and content of the specific resin particles contained in the toner are measured, and the results are shown in Table 2. .

<Preparation of Toner 14>
The crosslinked resin particles 1 were used as toner 14 as they were. The volume average particle diameter of the toner, the complex elastic modulus at 80 ° C., the tan δ value at 100 ° C. and 120 ° C., and the volume average particle diameter and content of the specific resin particles contained in the toner are measured, and the results are shown in Table 2. .

<Preparation of Toner 15>
A toner 15 was produced in the same manner as the toner 1 except that the crosslinked resin particles 1 were not used. The volume average particle diameter of the toner, the complex elastic modulus at 80 ° C., the tan δ value at 100 ° C. and 120 ° C., and the volume average particle diameter and content of the specific resin particles contained in the toner are measured, and the results are shown in Table 2. .

[Production of developer]
<Creation of carrier>
Ferrite particles (volume average particle size: 35 μm, GSDv: 1.20): 100 parts Toluene: 14 parts Methyl methacrylate-perfluorooctylethyl acrylate copolymer (copolymerization ratio 8: 2, Mw = 78000, critical Surface tension: 24 dyn / cm): 1.6 parts carbon black (trade name: VXC-72, manufactured by Cabot, volume resistivity: 100 Ωcm or less): 0.12 parts Crosslinked melamine resin particles (average particle size: 0) 0.3 μm, toluene insoluble): 0.3 part

First, carbon black was diluted in toluene and added to a perfluoroacrylate copolymer and dispersed with a sand mill. Next, the above components other than the ferrite particles were dispersed therein with a stirrer for 10 minutes to prepare a coating layer forming solution. Next, this coating layer forming liquid and ferrite particles were put into a vacuum degassing type kneader and stirred at a temperature of 60 ° C. for 30 minutes, and then the pressure was reduced and toluene was distilled off to form a resin coating layer to obtain a carrier. .
The volume average particle size distribution index GSDv of the carrier was 1.20.

<Production of developer>
36 parts of the obtained toner and 414 parts of the carrier were put in a 2 liter V blender, stirred for 20 minutes, and then sieved at 212 μm to prepare a developer.

[Evaluation of toner]
An unfixed image (monochromatic solid image of 5 cm square, toner amount 0.45 g / cm ² ) was produced using DocuCenter 9000 manufactured by Fuji Xerox Co., Ltd. as the image forming apparatus. As a recording medium, Premier 80 manufactured by Xerox Co., Ltd. was used. Using an off-line fixing device modified so that the fixing temperature is adjusted, an unfixed image is fixed while gradually increasing the fixing temperature from 130 ° C. to 5 ° C., and the minimum fixing temperature is evaluated. Further, the glossiness of the fixed image, the gloss unevenness, and the fixing device temperature after fixing the 300 sheets of images when the fixing temperature was set to 180 ° C. were evaluated. The results are shown in Tables 3 and 4. Note that the temperature of the fixing device after 300-image fixing is closer to the set fixing temperature, the smaller the temperature drop during continuous printing, and the better the fixing even when the image fixing speed is increased.

As an off-line fixing device, image fixing was performed using any one of the following fixing device 1 to fixing device 4.
Fixer 1: DocuCentre f1100GA fixing device The surface of a Teflon (registered trademark) tube having a thickness of 30 μm is directly applied to a substrate (aluminum substrate) with a heating roll of a Teflon (registered trademark) hard roll fixing device (two roll fuser). A layer is provided.
Fixing device 2: Soft roll A: A material having 300 μm of silicone rubber having a rubber hardness of 60 as an elastic layer between the base material and the surface layer in the fixing device 1.
Fixing device 3: Soft roll B: A material having 600 μm of silicone rubber having a rubber hardness of 60 as an elastic layer between the base material and the surface layer in the fixing device 1.
Fixing device 4: Soft roll A: A material having 200 μm of silicone rubber having a rubber hardness of 60 as an elastic layer between the base material and the surface layer in the fixing device 1.
The process speed (image fixing speed) of the fixing device is 535 mm / sec.

<Measurement of glossiness>
The glossiness of the fixed image was measured using a GM26D manufactured by Murakami Color Research Laboratory under the condition that the incident light angle to the sample was 75 degrees. The measured results are shown in Table 3 and Table 4 below.

<Evaluation of uneven gloss>
The gloss unevenness of the fixed image was visually evaluated.
A: There are few smoothed parts, and there is no gloss unevenness with a low gloss. O: A smooth part and a low gloss part coexist with a size of less than 0.5 mm, but there is little gloss unevenness.
(Triangle | delta): A smooth part and a low gloss part are mixed by the magnitude | size of 0.5 mm or more and less than 1.5 mm, and an image looks somewhat mottled.
X: A smooth portion and a low gloss portion are mixed in a size of 1.5 mm or more, and the image looks mottled.

<Minimum fixing temperature>
Using an off-line fixing device modified so that the fixing temperature is adjusted, an unfixed image was fixed while increasing the fixing temperature stepwise between 130 ° C. and 5 ° C. to prepare a fixing sample. The image after fixing was folded in half, and the width of the blank area of the image was measured. The temperature satisfying the fixing level at which the width was 0.5 mm or less was defined as the minimum fixing temperature. The measurement results are shown in Tables 3 and 4.

  From the results shown in Tables 3 and 4, it can be seen that in the example, the minimum fixing temperature is suppressed lower, the glossiness is suppressed, and the gloss unevenness is suppressed as compared with the comparative example.

10, 200 Image forming apparatus 12, 212 Photosensitive member (latent image holding member)
14, 214 Charging roller 16, 216 exposure device (electrostatic latent image forming means)
18, 218 Developing device (developing means)
20, 220 Transfer device 22, 222 Photoconductor cleaning device (toner removing means)
26, 226 Fixing device (fixing means)
28 toner cartridge 50 toner 52 binder resin 54 specific resin particle 210 process cartridge,
44, 250 Recording paper (transfer object)

Claims (6)

A binder resin containing a crystalline polyester resin and an amorphous polyester resin, a volume average particle size of 0.6 μm or more and 4.0 μm or less, and a softening temperature higher than the softening temperature of the amorphous polyester resin; High resin particles, and
A toner for developing an electrostatic latent image, wherein the complex elastic modulus of the toner at 80 ° C. is 5 × 10 ⁵ Pa or less.   An electrostatic latent image developing developer comprising the electrostatic latent image developing toner according to claim 1. Toner that is removed from the image forming apparatus and supplied to at least developing means provided in the image forming apparatus is stored.
The toner cartridge is the electrostatic latent image developing toner according to claim 1.   A process cartridge comprising developing means, wherein the developing means contains the developer for developing an electrostatic latent image according to claim 2. A latent image carrier,
An electrostatic latent image forming means for forming an electrostatic latent image on the surface of the latent image holding member;
Developing means for developing the electrostatic latent image with a developer containing toner to form a toner image;
Transfer means for transferring the toner image formed on the latent image holding member onto a transfer target;
Fixing means for fixing the toner image transferred onto the transfer object,
The image forming apparatus according to claim 2, wherein the developer is an electrostatic charge image developing developer.   The fixing unit includes a fixing member including a base material, an elastic layer having a thickness of 0 mm to 1 mm provided on the base material, and a surface layer provided on the elastic layer. The image forming apparatus described in 1.

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