JP2007065620A - Toner and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a toner excellent in hot storage stability and hot offset resistance while maintaining low-temperature fixability, and an image forming apparatus in which carrier adhesion is suppressed even in high-speed image formation, fixing in a low temperature region is possible, and a high quality image free of stain by hot offset is obtained. <P>SOLUTION: The toner includes at least a binder resin, a release agent, a colorant and a fatty acid amide compound, wherein the binder resin comprises at least an amorphous polyester (A) having a softening point in a low temperature region, an amorphous polyester (B) having a softening point in a high temperature region and a crystalline polyester (C), and a softening point TmC of the crystalline polyester (C), a surface temperature T<SB>H</SB>of a fixing member 14 and a softening point Tm(Asp) of the fatty acid amide compound satisfy the formula (1): TmC<Tm(Asp)<T<SB>H</SB>. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a toner for visualizing an electrostatic image formed on the surface of an image carrier such as a photoreceptor in electrophotography and electrostatic recording, and an image carrier such as a photoreceptor using the toner. The present invention relates to an electrophotographic image forming apparatus such as a copying machine, a printer, and a facsimile machine that visualizes an electrostatic charge image formed on a surface.

  As an electrophotographic method used in an image forming apparatus such as a laser printer or a dry electrostatic copying machine, a photoconductive insulating layer is uniformly charged (charging process), then the layer is exposed, and the exposed portion An electric latent image is formed by dissipating the charge (exposure process), and further visualized by attaching a fine powder having a colored charge called toner to the latent image (development process). After the transferred visible image is transferred onto a transfer material such as transfer paper (transfer process), the process is composed of a process of permanent fixing (fixing process) by heating, pressing or other suitable fixing methods.

  Among these, for the fixing step, for example, a contact heating fixing method such as heat roller fixing for fixing by heating and melting using a heat roll, a non-contact heating method such as oven fixing, or the like is used. In recent years, with the increasing demand for energy saving, there has been a demand for power saving in the fixing process, which accounts for a considerable portion of the power used by copying machines. However, the contact method is characterized by high thermal efficiency. Compared to the contact method, the temperature required for fixing can be lowered, which is effective for energy saving and copying machine miniaturization.

However, in this contact-type heat fixing method, there is a problem of offset development in which a part of the toner melted at the time of fixing is transferred to a heat roller and transferred to a subsequent transfer paper or the like.
In order to prevent this phenomenon, the surface of the heat roller has been conventionally processed with a material having excellent releasability such as fluorine resin, or a release agent such as silicone oil has been applied to the surface of the heat roller. Yes. However, the method using silicone oil or the like is not preferable because the fixing device is large and complicated, which may increase costs and cause trouble.
In addition, if the temperature of the hot roll is lowered to prevent the occurrence of the offset phenomenon, the temperature of the hot roll is too low, causing a problem that the toner is not sufficiently melted and fixing is insufficient. .
From the viewpoint of energy saving and device miniaturization, there is a demand for a toner having a higher hot offset generation temperature (hot offset resistance) and a lower fixing temperature (low temperature fixing property). In addition, the toner needs to be heat-resistant and preservable so that the toner does not block during storage and at ambient temperature in the apparatus.

To deal with such a problem, for example, Patent Document 1 has developed a binder resin obtained by mixing two types of resins having different softening points. In this method, the ratio of the resin to be mixed on the low softening point side is developed. Increasing the value, the low-temperature fixability is improved, but there is a problem with blocking resistance and hot offset resistance, and when the glass transition point on the low softening point side is increased, the blocking resistance is eliminated, Even if the ratio was increased, there was a limit to the high degree of compatibility between low-temperature fixability and hot offset resistance. Further, in such a method, there is a problem that the difference between the softening point of the polyester on the low softening point side and the minimum fixing temperature is large in the low temperature fixing region, and the sharp melt property in the low temperature region is not sufficient.
Therefore, in view of the recent increase in speed, size and energy saving of copying machines, further improvement in low-temperature fixing property and offset resistance is desired.

In Patent Document 2, a toner composition containing a modified polyester resin capable of reacting with a compound having an active hydrogen group in an organic solvent is dissolved and / or dispersed, and the solution or dispersion is used as an aqueous system containing resin fine particles. Disclosed is a toner for image formation, characterized in that, in a toner obtained by reacting with a crosslinking agent and / or an extender in a medium, the toner binder contains a crystalline polyester resin together with the modified polyester resin. Has been.
That is, in Patent Document 2, since the crystalline polyester added to the toner has crystallinity, the crystalline polyester exhibits a heat melting characteristic showing a sharp viscosity decrease near the fixing start temperature. It has good heat storage stability due to its properties, its viscosity rapidly decreases at the melting start temperature (sharp melt property), and is fixed on the transfer material, so a toner that has both good heat storage stability and low temperature fixability It can be provided.

Further, in Patent Document 3, in an electrophotographic toner containing a binder resin and a colorant, the binder resin mainly comprises the following (A), (B), and (C), and (A) a softening point of 120 to 170. A resin having a glass transition point of 58 to 75 ° C. and a chloroform insoluble fraction of 5 to 50% by mass; (B) a resin having a softening point of 90 to 120 ° C. and a glass transition point of 58 to 75 ° C .; C) a crystalline polyester resin having a melting point of 80 to 140 ° C .; and the chloroform-insoluble fraction of the binder resin is less than 30% by mass, and further has a penetration of 1.5 or less and a melting point of 80 to 110. An electrophotographic toner containing a wax (W) at 0 ° C. is disclosed.
That is, in the invention described in Patent Document 3, the resin (C), which is a crystalline polyester of a low-melting substance, is melt-kneaded into two types of resins (A) and (B) having different softening points, thereby (A ) And (B), (C) is uniformly dispersed, and a toner excellent in hot offset resistance and blocking resistance can be obtained while maintaining low-temperature fixability.

Further, for example, in Patent Document 4, a crystalline polymer having a melting point of 180 to 280 ° C. and an endotherm at a melting point measured using a differential scanning calorimeter (DSC) of 25 to 150 mJ / mg, and a glass transition A toner resin composition comprising an amorphous polyester having a temperature of 30 to 80 ° C., wherein the amorphous polyester comprises a non-crystalline polyester having a weight average molecular weight of 3000 to 20,000, and a weight average A resin composition for toner containing an amorphous polyester having a molecular weight of 30,000 to 300,000 is disclosed.
That is, in Patent Document 4, if the resin composition for toner of the present invention is used, a toner that is excellent in low-temperature fixability, high-temperature offset resistance, and anti-blocking property and can perform good color development can be produced. This is because, in the resin composition for toner of the present invention, the crystalline components in the crystalline polymer having a high melting point form a physically crosslinked structure in the amorphous polyester, while the crystalline component in the crystalline polymer having a high melting point is used. A non-crystalline component and non-crystalline polyester are intertwined to form a kind of network structure. By forming such a network structure, there is little decrease in viscosity at high temperatures, and low temperature fixability and storage stability. It is described that good offset resistance can be exhibited without lowering the thickness.

For example, in Patent Document 5, the binder resin is composed of at least a binder resin component (LR) and a binder resin component (HR), and the melt viscosity characteristic of the binder resin component (LR) is 1 × 10 ³ ( The temperature indicating Pa · s) is Tlr3 (° C.), the temperature indicating 1 × 10 ³ (Pa · s) in the melt viscosity characteristics of the binder resin component (HR) is Thr3 (° C.), and the crystalline resin component ( CR), the temperature at which the endothermic peak temperature by DSC shows 1 × 10 ³ (Pa · s) in the melt viscosity characteristic is Tcr3 (° C.), Tlr3 is 90 to 125 ° C., Thr3 is 155 to 210 A toner having a temperature of 95 ° C. and a Tcr3 of 95 to 150 ° C. is disclosed. That is, in Patent Document 5, by including a resin component having the above characteristics in the binder resin, it is possible to obtain a toner with good image quality, a wide fixing temperature range, and good blocking properties.

  In other words, in Patent Documents 2 to 5, by adding crystalline polyester to two types of polyester resins, the properties of each other resin are maintained even when a plurality of resins having greatly different softening point regions are mixed. In the inventions disclosed in Patent Documents 2 to 5, after adding a crystalline polyester to the amorphous polyester and heating it once, the amorphous polyester and the crystalline This causes a problem that the properties of each resin cannot be obtained due to compatibility with the reactive polyester.

  For example, in Patent Document 6, 100 parts by weight of polyester crystalline resin having a ratio of the softening point to the maximum peak temperature of the heat of fusion (softening point / peak temperature) of 0.6 to 1.3 and the particles are dealt with. A method for producing a toner by melting and kneading 0.1 to 10 parts by weight of inorganic fine particles having a diameter of 20 nm to 3 μm is disclosed. That is, in Patent Document 6, a crystalline resin is melted and kneaded with inorganic fine particles having a specific particle diameter, so that the crystalline resin is more easily crystallized in the binder resin, and a toner having excellent low-temperature fixability is efficiently obtained. Although the toner obtained by the invention disclosed in Patent Document 6 can be manufactured, the chargeability fluctuates by adding inorganic fine particles, and the elastic modulus of the particles fluctuates. There arises a problem that the shape becomes non-uniform and a difference in toner fixability appears.

By the way, in recent years, when developing using the above-described toner, a two-component developer composed of a toner and a carrier (from the viewpoint of transferability, halftone reproducibility, stability of development characteristics with respect to temperature and humidity, etc.) Hereinafter, the two-component development method using simply “developer”) is mainly used.
In a developing device using this two-component development system, the developer is held in a brush-like manner on the developer carrying member and conveyed to a developing area where the developer carrying member and the latent image carrying member face each other. . Then, in the development area, the brush-like developer is rubbed against the surface of the latent image carrier, and the toner in the developer is supplied to the electrostatic latent image portion on the latent image carrier to form an electrostatic latent image. The so-called brush development is performed.

In the image forming apparatus of the magnetic brush developing system, the smaller the average particle diameter of the carrier used, the more accurately each latent image can be reproduced, and the image quality and character reproducibility of the formed image are improved. Furthermore, it is known that the graininess, which is the smoothness of the appearance of characters, is improved. That is, when a carrier having a small particle diameter is used in the magnetic brush development method, each latent image can be faithfully reproduced, so that a high-definition image can be easily obtained.
On the other hand, however, when a carrier having a small particle diameter is used, the magnetic force per one particle of the carrier is lowered, so that there is a problem that so-called carrier adhesion in which the carrier adheres to a non-image portion on the image carrier is likely to occur. .
Carrier adhesion occurs as follows. Usually, the carrier is held on the developing sleeve by a magnetic force, but at the same time, the carrier itself has a charge, and an electrostatic force acts between the carrier and the charge on the image carrier. When the electrostatic force between the carrier and the image carrier overcomes the holding force by the magnetic force of the developing sleeve, the carrier moves onto the image carrier.
When carrier particles having a small particle diameter are used, the magnetic force per carrier particle is reduced, so that the carrier easily moves to the surface of the photoconductor, and the carrier adhered on the photoconductor causes image defects. Let That is, image noise occurs when the carrier transferred to the photoconductor is fixed on a transfer body such as paper, and white spots occur when the carrier is not transferred.

The phenomenon of carrier adhesion is more likely to occur when the image forming speed during image formation is increased. This is because the linear velocity of the developing sleeve increases as the speed increases, and the centrifugal force acting on the developer adhering to the developing sleeve increases, so that when the magnetic brush composed of the developer contacts the surface of the photosensitive drum. This is because the carrier of the magnetic brush is easily released from the magnetic brush.
In recent years, the demand for speeding up image forming apparatuses has increased, and the speeding up capability of the apparatus main body has greatly improved. However, as described above, when carrier particles are released from the magnetic brush on the developing sleeve, the released carrier is attached to the photosensitive drum, and the carrier attachment described above is induced.
The carrier adhering to the photoconductive drum causes image disturbance or dot dropout in the image, thereby degrading the image quality and damaging parts arranged around the photoconductive drum. There is a risk of causing this problem.

As a means for preventing carrier adhesion from occurring when a small particle size carrier is used as a developer, for example, in Patent Document 1, the surface of a developer carrier disposed opposite to a latent image carrier is disclosed. Forming a developer layer, developing the electrostatic latent image on the latent image carrier using the formed developer layer to obtain a toner image, and transferring the toner image onto the transfer member. And a fixing step of fixing the transferred toner image, wherein the developer carrying member has a developing magnetic pole having a main pole magnetic force of 100 mT or more inside, and the developer. Discloses an image forming method using a carrier having a volume average particle diameter of 50 μm or less and a process speed of 200 mm / second or more.
That is, in Patent Document 1, when the process speed for forming a copy image is increased, a developing magnetic pole having a large main pole magnetic force is disposed inside the developer carrier (developing roll), thereby reducing the particle size. An image forming method is disclosed in which a carrier is not transferred to a latent image carrier even in a high-speed image forming process using a two-component developer.
However, even in the method disclosed in Patent Document 1, it is difficult to completely suppress the phenomenon of carrier adhesion, and the toner on the developing sleeve is too strong because the magnetic force on the surface of the developer carrying member is too strong. Part of the toner does not move onto the photosensitive member, causing fogging on the image, or it is necessary to arrange a developing magnetic pole having a large magnetic force inside the developing roll, which increases the manufacturing cost. There's a problem.
In a two-component developing type image forming apparatus, it is desired that a high-quality image with high definition can be obtained without generating an abnormal image due to carrier adhesion or the like even when the process speed is increased.

JP-A-4-362956 JP 2004-302458 A JP 2003-57875 A JP 2004-151709 A Japanese Patent Laid-Open No. 2005-164800 JP 2004-309517 A JP 2000-172078 A

In view of the above problems, an object of the present invention is to provide a toner that is excellent in heat-resistant storage stability and hot offset resistance while maintaining low-temperature fixability.
Further, in a two-component development type image forming apparatus, fixing in a low temperature region is possible, there is no stain on the image due to hot offset, and there is no occurrence of an abnormal image due to carrier adhesion even if high-speed image formation is performed. Another object of the present invention is to provide an image forming apparatus capable of obtaining a high-quality image in long-term use.

The features of the present invention, which is a means for solving the above problems, are listed below.
The toner according to the present invention is a toner that develops an electrostatic latent image on a latent image carrier, is transferred onto a transfer target, and is fixed with heat and / or pressure by a fixing member to form a toner image. The binder resin contains at least a binder resin, a release agent, and a colorant, and the binder resin has an amorphous polyester (A) having a softening point of 70 to 140 ° C. and a softening point. A non-crystalline polyester (B) having a temperature of 120 to 190 ° C. and a crystalline polyester (C), the toner contains a fatty acid amide compound, and the softening point of the crystalline polyester (C) is defined as TmC. When the temperature of the surface of the fixing member is T _H and the softening point Tm (Asp) of the fatty acid amide compound, the following formula (1) is satisfied. _{TmC <Tm (Asp) <T} H ··· (1)
In this case, it is preferable that the crystalline polyester (C) forms a domain part in the toner.
Moreover, it is preferable that at least a part of the fatty acid amide compound is contained in the domain part.
Moreover, it is preferable that the softening point TmA of the amorphous polyester (A) and the softening point TmB of the amorphous polyester (B) satisfy the relationship of TmA <TmB-10 ° C.
Moreover, it is preferable that the softening point TmA of the amorphous polyester (A) and the softening point TmC of the crystalline polyester (C) satisfy the relationship of TmC−40 ° C. ≦ TmA ≦ TmC.
Moreover, the said crystalline polyester (C) shall have a softening point of 80-140 degreeC.
The ratio G′100 / G′150 of the storage elastic modulus G′100 at 100 ° C. and the storage elastic modulus G′150 at 150 ° C. of the amorphous polyester (B) is 3.0 to 30.0. It can be.
The toner preferably has a Tg in the range of 35 to 70 ° C.
The fatty acid amide compound may be an alkylene bis fatty acid amide.
The fatty acid amide compound is preferably ethylene bis stearic acid amide.
The toner is preferably produced by melt-kneading and then pulverizing.
The release agent preferably contains at least two types of wax, and at least one of the waxes is preferably a hydrocarbon wax.
The amorphous polyester (A) and / or the amorphous polyester (B) can be produced using at least an inorganic tin compound or a compound containing titanium as a catalyst.
The crystalline polyester (C) can be produced using at least an inorganic tin compound or a compound containing titanium as a catalyst.
The toner preferably has an average circularity of 0.85 to 0.95.
The toner has a volume average particle diameter of 3.0 to 13.0 μm and a ratio (Dv / Dn) of the volume average particle diameter (Dv) to the number average particle diameter (Dn) of 1.00 to 1.1.0. It is preferable to be in the range of 40.
The toner preferably has a shape factor SF-1 in the range of 100 to 180 and a shape factor SF-2 in the range of 100 to 180.
Further, the toner may contain a magnetic material.
The toner may be used by mixing with a magnetic carrier coated with a resin.

An image forming apparatus according to the present invention includes an image carrier that carries at least a latent image, and a developer carrier that carries and conveys a two-component developer including a toner and a carrier. A developing unit that supplies toner to the latent image on the image carrier by the body to visualize the latent image, a transfer unit that transfers the visible image on the surface of the image carrier onto the fixing medium, and a fixing unit on the fixing medium. 20. An image forming apparatus comprising: a fixing unit that fixes a visible image by applying heat and / or pressure with a fixing member, wherein the toner used in the developing unit is any one of claims 1 to 19. The carrier used in the developing means is (a) a volume average particle diameter Dvc of 50 μm to 125 μm, and (b) a carrier having a particle diameter of less than 0.4 Dvc is 0.1% by weight or less. Having a particle size distribution of Carrier particle size of less than c) 0.4Dvc more 0.6Dvc is an image forming apparatus, wherein those having a particle size distribution is 4.0 wt% or less. _{TmC <Tm (Asp) <T} H ··· (1)
In the image forming apparatus, it is preferable that a linear velocity Va of the developer carrier is Va> 650 mm / second.

  According to the present invention, it is possible to provide a toner that is excellent in low-temperature fixability and excellent in heat-resistant storage stability and hot offset resistance. Thereby, in the fixing device of the image forming apparatus, it is possible to achieve a level of energy saving that is not conventional. Further, an image forming apparatus using the toner as a developer can form a high-quality image without an abnormal image due to carrier adhesion or hot offset.

The toner according to the present invention contains at least a binder resin, a release agent (W), a colorant, and a fatty acid amide compound, and an amorphous polyester (A) having a predetermined softening point in the binder resin. ) and the amorphous polyester (B), contains a crystalline polyester (C), a further softening point TmC of the crystalline polyester (C), the temperature T _H of the fixing roller surface of a fixing member, wherein the fatty acid A toner in which the softening point Tm (Asp) of the amide compound satisfies the relationship of the following formula (1).

(Equation 1)
_{TmC <Tm (Asp) <T} H ··· (1)

As the amorphous polyesters (A) and (B), polyesters obtained by a normal production method can be used. Polyester usually uses a divalent or higher valent alcohol monomer component and a divalent or higher carboxylic acid component such as a carboxylic acid, a carboxylic acid anhydride or a carboxylic acid ester as raw material monomers, and these are subjected to a condensation polymerization reaction. Can be obtained.
In particular, amorphous polyester uses at least a trihydric or higher polyhydric alcohol monomer or a trivalent or higher polyvalent carboxylic acid monomer as the above raw material monomer, and by subjecting these to a polycondensation reaction. can get. Amorphous polyester can also be obtained by polycondensation of a trihydric or higher polyhydric alcohol monomer and a trivalent or higher polyvalent carboxylic acid monomer.

Examples of the divalent alcohol monomer component include polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene (3.3) -2,2-bis (4 -Hydroxyphenyl) propane, polyoxypropylene (2.0) -2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene (2.0) -polyoxyethylene (2.0) -2,2- Alkylene oxide adducts of bisphenol A such as bis (4-hydroxyphenyl) propane and polyoxypropylene (6) -2,2-bis (4-hydroxyphenyl) propane, ethylene glycol, diethylene glycol, triethylene glycol, 1,2 -Propylene glycol, 1,3-propylene glycol, 1,4-butanediol, ne Pentyl glycol, 1,4-butenediol, 1,5-pentanediol, 1,6-hexanediol, 1,4-cyclohexanedimethanol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, bisphenol A, A propylene adduct of bisphenol A, an ethylene adduct of bisphenol A, hydrogenated bisphenol A, or the like can be used.
Among these, an alkylene oxide adduct having 2 or 3 carbon atoms (average number of added moles of 1 to 10) of bisphenol A, ethylene glycol, propylene glycol, 1,6-hexanediol, bisphenol A, hydrogenated bisphenol A, or the like is used. Is preferred.

Examples of the trivalent or higher alcohol monomer component include sorbitol, 1,2,3,6-hexanetetrol, 1,4-sorbitan, pentaerythritol, dipentaerythritol, tripentaerythritol, 1,2, 4-butanetriol, 1,2,5-pentanetriol, glycerol, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane, 1,3,5-tri Hydroxymethylbenzene or the like can be used.
Among these, it is preferable to use sorbitol, 1,4-sorbitan, pentaerythritol, glycerol, trimethylolpropane and the like.

  Amorphous polyester (A), (B) applied to the present invention may be a single monomer or a plurality of monomers from these dihydric alcohol monomers and trihydric or higher polyhydric alcohol monomers. Can be used.

Examples of the divalent carboxylic acid monomer component as the acid component include various dicarboxylic acids, succinic acid substituted with an alkyl group or alkenyl group having 1 to 20 carbon atoms, anhydrides of these acids and alkyls (carbon number). 1-12) Esters can be used.
Specifically, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, phthalic acid, isophthalic acid, terephthalic acid, succinic acid, adipic acid, sebacic acid, azelaic acid, malonic acid, n-dodecenyl succinic acid, n -Dodecyl succinic acid, n-octyl succinic acid, isooctenyl succinic acid, isooctyl succinic acid, anhydrides of these acids, lower alkyl esters, and the like.
Among these, it is preferable to use maleic acid, fumaric acid, terephthalic acid, or succinic acid substituted with an alkenyl group having 2 to 20 carbon atoms.

Examples of the trivalent or higher polyvalent carboxylic acid monomer component include 1,2,4-benzenetricarboxylic acid, 2,5,7-naphthalenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, 2,4-butanetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, 1,3-dicarboxyl-2-methyl-2-methylenecarboxypropane, 1,2,4-cyclohexanetricarboxylic acid, tetra (methylenecarboxyl) Examples thereof include methane, 1,2,7,8-octanetetracarboxylic acid, pyromellitic acid, empole trimer acid, acid anhydrides thereof, and lower alkyl esters. Preferably, a trivalent carboxylic acid or a derivative thereof is used. In the present invention, these divalent carboxylic acid monomers and trivalent or higher polyvalent carboxylic acid monomers can be used alone or in combination.
Among these, it is preferable to use 1,2,4-benzenetricarboxylic acid and acid anhydrides thereof, alkyl esters having an alkyl group having 1 to 12 carbon atoms, and the like.

  The manufacturing method of polyester is not specifically limited, It can manufacture by esterification reaction or transesterification reaction using said each monomer. When polymerizing the raw material monomer, a commonly used esterification catalyst such as dibutyltin oxide may be appropriately used in order to accelerate the reaction.

  The molecular structure of the amorphous polyesters (A) and (B) is not particularly limited. In particular, the alcohol component contains at least one of bisphenol A propylene oxide adduct and bisphenol A ethylene oxide adduct as an alcohol component. It is preferable that the acid component has an unsaturated double bond between carbons. In particular, it is more preferable that fumaric acid, maleic acid and derivatives thereof are contained in the constituent components.

As described above, the polyester component is obtained by polycondensation using a divalent or higher valent alcohol monomer component and a carboxylic acid monomer component such as a divalent or higher carboxylic acid, carboxylic acid anhydride, or carboxylic acid ester as raw material monomers. be able to.
Examples of the raw material monomer of the amide component in the polyester, polyamide, or polyamide preferably used in this embodiment include various known polyamines, aminocarboxylic acids, amino alcohols, and the like, preferably hexamethylenediamine and ε-caprolactam.

The softening point of the amorphous polyester (A) is 70 to 140 ° C, and the softening point of the amorphous polyester (B) is 120 to 190 ° C.
The softening point TmA of the amorphous polyester (A) is desirably low as long as the blocking resistance of the toner does not deteriorate, but if the softening point is less than 70 ° C., the blocking resistance deteriorates. On the other hand, when the softening point TmA of the amorphous polyester (A) exceeds 140 ° C., the low-temperature fixability deteriorates. Further, when the softening point TmB of the amorphous polyester (B) is less than 120 ° C., the hot offset resistance and blocking resistance deteriorate, and when it exceeds 190 ° C., sufficient fixing properties are obtained in the operating temperature range of the fixing member. Cannot be obtained.
The binder resin contains an amorphous polyester (A) having a softening point in the low temperature region and an amorphous polyester (B) having a softening point in the high temperature region, so that the hot offset resistance can be obtained together with the low temperature fixability. A toner having excellent properties can be obtained.

  The measuring method of the softening point of the polyester resin is based on a method based on JIS K2207 (ring and ball method).

The molecular weight of the amorphous polyester (A) used in the present invention is such that the weight-average molecular weight (Mw) is 7000-30000, the number-average molecular weight (Mn) is 1000-10000, The Mw / Mn ratio is preferably 2.0 to 20.0. Further, the molecular weight of the amorphous polyester (B) is the molecular weight distribution by GPC of the THF-soluble component, the weight average molecular weight (Mw) is 10,000 to 200,000, the number average molecular weight (Mn) is 1000 to 15000, and its Mw / It is preferable that Mn ratio is 5.0-50.0.
The molecular weight distribution of the amorphous polyesters (A) and (B) is based on a molecular weight distribution chart in which the horizontal axis is log (M: molecular weight) and the vertical axis is weight%. In the case of the amorphous polyesters (A) and (B) used in the present invention, it is preferable to have a molecular weight peak in the range of 2.5 to 10.0 (% by weight) in this molecular weight distribution diagram.

The softening point TmA of the amorphous polyester (A) and the softening point TmB of the amorphous polyester (B) preferably satisfy the relationship of TmA <TmB-10 ° C.
When TmA and TmB satisfy the relationship of TmA <TmB−10 ° C., fixing in a lower temperature region becomes possible, hot offset resistance in a higher temperature region is ensured, and toner having a wider fixable region can be obtained. can get.
When TmA is equal to or higher than (TmB-10) ° C., the low-temperature fixability is deteriorated and the hot offset resistance is deteriorated, so that a fixed fixable area cannot be secured.

The toner of the present invention contains the crystalline polyester (C) in addition to the amorphous polyesters (A) and (B) in the binder resin.
In the present invention, “crystallinity” means that the ratio of the softening point to the maximum peak temperature of heat of fusion by DSC (softening point / peak temperature) is 0.9 or more and less than 1.1, preferably 0.98 to 1.05. In addition, the term “amorphous” means that the ratio of the softening point to the maximum peak temperature of the heat of fusion (softening point / peak temperature) is 1.1 to 4.0, preferably 1.5 to 3. It means 0.

Usually, the amorphous resin used for the binder resin gradually decreases in melt viscosity from Tg, so that the Tg of the toner and the temperature at which the toner can be fixed on the fixing medium (for example, the outflow start temperature T (f1 / f1 / In order to improve the low-temperature fixability of the toner, it is necessary to lower the resin softening point by lowering the glass transition temperature of the resin or lowering the molecular weight. was there. However, in this case, the heat resistant storage stability and hot offset resistance of the toner are insufficient.
In contrast, the crystalline polyester (C) undergoes a crystal transition near the glass transition temperature (Tg), and at the same time, the melt viscosity suddenly decreases from the solid state and exhibits a fixing function to a recording medium such as paper. To reach a viscosity.
The present invention employing the crystalline polyester (C) exhibits a heat-melting characteristic that shows a sudden viscosity drop near the fixing start temperature. Therefore, the binder resin is mixed with the amorphous polyester and mixed at a low temperature. It is possible to obtain a toner having good fixing properties and good blocking resistance and hot offset resistance.

  The crystalline polyester (C) having crystallinity is composed of a crystalline aliphatic polyester resin containing an ester bond represented by the following general formula (I) in its molecular main chain.

  In the formula (I), R represents a linear unsaturated aliphatic divalent carboxylic acid residue, and is a linear unsaturated aliphatic group having 2 to 20 carbon atoms, preferably 2 to 4 carbon atoms. n is an integer of 2 to 20, more preferably an integer of 2 to 6.

The presence of the structure of the general formula (I) can be confirmed by solid C ¹³ -NMR.
Specific examples of the linear unsaturated aliphatic group include linear unsaturated divalent carboxylic acids such as maleic acid, fumaric acid, 1,3-n-propene dicarboxylic acid, and 1,4-n-butene dicarboxylic acid. Mention may be made of linear unsaturated aliphatic groups derived from acids.

(CH ₂ ) n represents a linear aliphatic dihydric alcohol residue. Specific examples of linear aliphatic divalent or trivalent or higher alcohol residues include linear fatty acids such as ethylene glycol, 1,3-propylene glycol, 1,4-butanediol, and 1,6-hexanediol. Those derived from group II dihydric alcohols.
The crystalline polyester (C) has a crystalline structure when the linear unsaturated aliphatic dicarboxylic acid is used as the acid component, compared to when the aromatic dicarboxylic acid is used as the acid component. It is easy to be done.

A small amount of other polyvalent carboxylic acid can be added to the dicarboxylic acid component. The polyvalent carboxylic acid includes (i) an unsaturated aliphatic divalent carboxylic acid having a branched chain, (ii) a saturated aliphatic polyvalent carboxylic acid such as a saturated aliphatic divalent carboxylic acid and a saturated aliphatic trivalent carboxylic acid. In addition to acids, (iii) aromatic polyvalent carboxylic acids such as aromatic divalent carboxylic acids and aromatic trivalent carboxylic acids are included.
The addition amount of these polyvalent carboxylic acids is usually 30 mol% or less, preferably 10 mol% or less, based on the total carboxylic acid, and is appropriately added within the range where the resulting polyester has crystallinity.

  Specific examples of polyvalent carboxylic acids that can be added as needed include malonic acid, succinic acid, glutaric acid, adipic acid, suberic acid, sebacic acid, citraconic acid, phthalic acid, isophthalic acid, terephthalic acid, etc. A divalent carboxylic acid of: trimetic anhydride, 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, 1,2,4-cyclohexanetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, And trivalent or higher polyvalent carboxylic acids such as 1,2,5-hexanetricarboxylic acid, 1,3-dicarboxyl-2-methylenecarboxypropane, 1,2,7,8-octanetetracarboxylic acid, etc. it can.

In addition to a small amount of an aliphatic branched dihydric alcohol or cyclic dihydric alcohol, a trihydric or higher polyhydric alcohol can be added to the polyhydric alcohol component. The addition amount is 30 mol% or less, preferably 10 mol% or less, based on the total alcohol, and is appropriately added within the range in which the resulting polyester has crystallinity.
Examples of the polyhydric alcohol to be added include 1,4-bis (hydroxymethyl) cyclohexane, polyethylene glycol, bisphenol A ethylene oxide adduct, bisphenol A propylene oxide adduct, glycerin and the like.

The crystalline polyester (C) is a polyvalent compound comprising (i) a linear unsaturated aliphatic divalent carboxylic acid or a reactive derivative thereof (an acid anhydride, a lower alkyl ester having 1 to 4 carbon atoms, an acid halide, etc.). It can be produced by subjecting a carboxylic acid component and (ii) a polyhydric alcohol component comprising a linear aliphatic diol to a polycondensation reaction by a conventional method.
The polyester in the present invention can be obtained by performing a dehydration condensation reaction or a transesterification reaction using the above raw material components in the presence of a catalyst. The reaction temperature and reaction time are not particularly limited, but are usually 20 to 300 ° C. and 30 minutes to 24 hours.

  As a catalyst for performing the above-described reaction, for example, zinc oxide, stannous oxide, dibutyltin oxide, dibutyltin dilaurate, or the like can be appropriately used. In addition, each physical property of resin (A)-(C) demonstrated above, ie, adjustment of a softening point, melting | fusing point, a glass transition point, and a chloroform insoluble fraction, is a raw material monomer at the time of manufacturing each resin, a polymerization start This can be easily carried out by selecting the type of agent or catalyst, the amount thereof, and the reaction conditions.

For example, an inorganic tin (II) compound or a titanium-containing compound is used as a catalyst for the reaction for producing the amorphous polyesters (A), (B) and the crystalline polyester (C). Can do.
An inorganic tin (II) compound refers to a tin compound having no Sn-C bond. For example, having carboxylic acid groups such as tin (II) oxalate, tin (II) diacetate, tin (II) dioctanoate, tin (II) dilaurate, tin (II) distearate, tin (II) dioleate Tin (II) compounds, dioctyloxytin (II), dilauroxytin (II), distearoxytin (II), tin (II) compounds having an alkoxy group such as dioleyloxytin (II), tin oxide ( II) or tin (II) halides such as tin (II) chloride and tin (II) bromide. Of these, tin (II) dioctanoate, tin (II) distearate, and tin (II) oxide are preferably used.

Moreover, it is also possible to use the compound containing titanium instead of an inorganic tin (II) compound.
Examples of the catalyst containing titanium include titanium halide, titanium diketone enolate, titanium carboxylate, titanyl carboxylate, and titanyl carboxylate.

  Specific examples of these are exemplified below. Among the titanium-containing catalysts described above, examples of the titanium halide include dichlorotitanium, trichlorotitanium, tetrachlorotitanium, trifluorotitanium, tetrafluorotitanium, and tetrabromotitanium.

  Examples of the titanium diketone enolate include titanium acetylacetonate, titanium diisopropoxide bisacetylacetonate, and titanyl acetylacetonate. Of these titanium diketone enolates, titanium acetylacetonate is preferably used.

  As titanium carboxylate, C1-C32 aliphatic carboxylate titanium, C7-38 aromatic titanium carboxylate, etc. are mentioned, for example. In the case of titanium polycarboxylate having a valence of 2 or more, the number of carboxyl groups coordinated to titanium may be one or more, and a free carboxyl group may exist without being coordinated to titanium.

  Examples of the aliphatic carbonic acid titanium having 1 to 32 carbon atoms include aliphatic monocarboxylic acid titanium, aliphatic dicarboxylic acid titanium, aliphatic tricarboxylic acid titanium, and tetravalent to octavalent or higher aliphatic polycarboxylic acid titanium. Is mentioned.

  Examples of the aliphatic monocarboxylic acid titanium include titanium formate, titanium acetate, titanium propionate, and titanium octoate. The aliphatic dicarboxylic acid titanium is not particularly limited, and examples thereof include titanium oxalate, titanium succinate, titanium maleate, titanium adipate, and titanium sebacate. Although it does not specifically limit as aliphatic tricarboxylic acid titanium, For example, hexane tricarboxylic acid titanium, isooctane tricarboxylic acid titanium, etc. are mentioned. Although it does not specifically limit as aliphatic tricarboxylic acid titanium, For example, octane tetracarboxylic acid titanium, decane tetracarboxylic acid titanium, etc. are mentioned.

  Examples of the aromatic carbonic acid titanium having 7 to 38 carbon atoms include aromatic monocarboxylic acid titanium, aromatic dicarboxylic acid titanium, aromatic tricarboxylic acid titanium, and tetravalent to octavalent or higher aromatic polycarboxylic acid titanium. Is mentioned.

Examples of the aromatic titanium monocarboxylate include titanium benzoate. The aromatic titanium dicarboxylate is not particularly limited. For example, titanium phthalate, titanium terephthalate, titanium isophthalate, titanium 1,3-naphthalenedicarboxylate, titanium 4,4-biphenyldicarboxylate, 2,5-toluenedicarboxylic acid Examples thereof include titanium oxide and titanium anthracene dicarboxylate. Although it does not specifically limit as aromatic tricarboxylic acid titanium, For example, trimellitic acid titanium, 2,4,6 mononaphthalene tricarboxylic acid titanium etc. are mentioned. Although it does not specifically limit as aromatic polycarboxylic acid titanium, For example, pyromellitic acid titanium, 2,3,4,6- naphthalene tetracarboxylic acid titanium etc. are mentioned.
Among these titanium carboxylates, an aromatic titanium carboxylate having 7 to 38 carbon atoms is preferable, and an aromatic titanium dicarboxylate is more preferable.

  Examples of titanyl carboxylate include titanyl aliphatic carboxylate having 1 to 32 carbon atoms, titanyl aromatic carboxylate having 7 to 38 carbon atoms, and the like. In the case of divalent or higher polycarboxylic acid titanyl, the number of carboxy groups coordinated to titanium may be one or more, and a free carboxyl group may be present without coordination to titanium.

  Examples of the aliphatic carboxylate titanyl having 1 to 32 carbon atoms include, for example, titanyl aliphatic monocarboxylate, titanyl aliphatic dicarboxylate, titanyl aliphatic tricarboxylate, and titanyl 4- to 8- or higher aliphatic polycarboxylate. Is mentioned.

  Examples of the aliphatic monocarboxylic acid titanyl include titanyl formate, titanyl acetate, titanyl propionate, and titanyl octoate. Although it does not specifically limit as aliphatic dicarboxylate titanyl, For example, titanyl oxalate, titanyl succinate, titanyl maleate, titanyl adipate, titanyl sebacate, etc. are mentioned. Although it does not specifically limit as aliphatic tricarboxylic acid titanyl, For example, hexane tricarboxylic acid titanyl, isooctane tricarboxylic acid titanyl, etc. are mentioned. Although it does not specifically limit as a 4-8 valent or more aliphatic polycarboxylic acid titanyl, For example, an octane tetracarboxylic-acid titanyl, a decane tetracarboxylic-acid titanyl, etc. are mentioned.

  Examples of the aromatic carboxylate titanyl having 7 to 38 carbon atoms include, for example, titanyl aromatic monocarboxylate, titanyl aromatic dicarboxylate, titanyl aromatic tricarboxylate, and titanyl 4- to 8- or higher aromatic polycarboxylate. Is mentioned.

  Examples of the titanyl aromatic monocarboxylate include titanyl benzoate. Although it does not specifically limit as aromatic dicarboxylate titanyl, For example, titanyl phthalate, titanyl terephthalate, titanyl isophthalate, titanyl 1,3-naphthalenedicarboxylate, titanyl 4,4-biphenyl dicarboxylate, 2,5-toluene dicarboxylic Examples thereof include titanyl acid and titanyl anthracene dicarboxylate. The aromatic tricarboxylic acid titanyl is not particularly limited, and examples thereof include titanyl trimellitic acid and titanyl 2,4,6-naphthalene tricarboxylic acid. Although it does not specifically limit as 4- to 8-valent or more aromatic polycarboxylic acid titanyl, For example, titanyl pyromellitic acid, titanyl 2,3,4,6-naphthalene tetracarboxylic acid, etc. are mentioned.

  Examples of the titanyl carboxylate include, for example, titanyl aliphatic dicarboxylate, titanyl aliphatic tricarboxylate, 4- to 8- or higher-valent aliphatic polycarboxylic acid titanyl, aromatic dicarboxylic acid titanyl, aromatic tricarboxylic acid titanyl, or 4 Alkali metal (lithium, sodium, potassium, etc.) or alkaline earth metal (magnesium, calcium, barium, etc.) salts, etc. of titanyl carboxylate listed in ˜8 or higher aromatic polycarboxylic acid titanyl . Of these carboxylic acid titanyl salts, maleic acid titanyl salt and oxalic acid titanyl salt are preferred.

With respect to the amount of the titanium-containing catalyst used, the lower limit is preferably 0.01%, more preferably 0.02%, more preferably 0.02%, based on the total weight of the polyol and polycarboxylic acid used to obtain the polyester resin shown below. 03% is particularly preferred and 0.05% is most preferred. The upper limit is preferably 5%, more preferably 2%, particularly preferably 1.5%, and most preferably 0.8%. When it is 0.01% or more, the effect as a polycondensation catalyst is sufficiently obtained, and when it is 5% or less, high catalytic action is obtained according to the amount of catalyst. In addition, when the amount is within the above-mentioned range of the catalyst amount, the necessary properties of the toner using the toner binder made of the polyester resin to be obtained become better.
In the above and below, “%” means “% by weight” unless otherwise specified.

  Among these titanium-containing catalysts, preferred are titanium diketone enolate, titanium carboxylate, titanyl carboxylate and combinations thereof, more preferably titanium diketone enolate, aromatic carboxylic acid titanium, aliphatic carboxylic acid. Acid titanyl salts, aromatic carboxylic acid titanyl salts and combinations thereof, more preferably, among titanium acetylacetonate, aromatic dicarboxylic acid titanium, and carboxylic acid titanyl salts, alkali metal salts and combinations thereof, particularly preferable. Is titanium terephthalate, titanium isophthalate, titanium orthophthalate, titanyl oxalate, titanyl maleate and combinations thereof, most preferably titanium terephthalate, potassium titanyl oxalate and combinations thereof.

  The molecular weight distribution of the crystalline polyester (C) is preferably sharp from the viewpoint of low-temperature fixability, and the molecular weight is preferably a relatively low molecular weight. The molecular weight of the polyester (C) is such that the weight average molecular weight (Mw) is 8000 to 32000, the number average molecular weight (Mn) is 2500 to 10,000, and its Mw / M in the molecular weight distribution by GPC of the o-dichlorobenzene soluble component. It is preferable that the Mn ratio is 1.5 to 6.0.

Whether or not the crystalline polyester (C) has crystallinity can be confirmed by whether or not a peak exists in the X-ray diffraction pattern by the powder X-ray diffractometer. The polyester resin (C) having crystallinity used in the present invention has a diffraction pattern in which at least one diffraction peak exists at a position where 2θ is 20 ° to 25 °, and preferably 2θ is at least (i ) 19 ° to 20 °, (ii) 21 ° to 22 °, (iii) 23 ° to 25 ° and (iv) 29 ° to 31 °.
The powder X-ray diffraction measurement is performed by using Rigaku Denki RINT1100, using a wide-angle goniometer under the conditions that the tube is Cu and the tube voltage-current is 50 kV-30 mA.

  Moreover, it is preferable that the softening point TmA of the amorphous polyester (A) and the softening point TmC of the crystalline polyester (C) have the relationship of the following formula (2).

(Equation 2)
TmC-40 ° C. ≦ TmA ≦ TmC (2)

Since the amorphous polyester ester (A) and the crystalline polyester (C) satisfy the relationship of the above formula (2), the low-temperature fixability is good, and it has a sharp melt property in a low-temperature region. Below the fixing start temperature, it is difficult to soften and has good blocking resistance, and above the fixing start temperature, it is possible to obtain a toner that is easily softened and has high fixing strength.
When the softening point TmA of the amorphous polyester (A) is higher than the softening point of the crystalline polyester (C), the low-temperature fixability is deteriorated. Further, when the softening point TmA of the amorphous polyester (A) is lower than (TmC-40) ° C., the width between the toner softening temperature and the fixing start temperature in the low temperature region becomes large, and the sharp melt near the fixing start temperature. Lack of sex.

  In the crystalline polyester (C), the softening point TmC is preferably 80 to 140 ° C. When the softening point TmC of the crystalline polyester (C) is less than 80 ° C., sufficient hot offset resistance and blocking resistance of the toner cannot be obtained, and when it exceeds 140 ° C., the low-temperature fixability decreases.

In the toner of the present invention, the crystalline polyester (C) is preferably present in an incompatible state with the amorphous polyesters (A) and (B). That the crystalline polyester (C) and the amorphous polyester are in an incompatible state means that the domain of the crystalline polyester (C) remains in the toner and is in a phase separated state. The dissolved state means a state in which no crystal structure portion remains. When the crystalline polyester (C) and the amorphous polyester form a shared domain and are in a compatible state, the two resins cannot sufficiently exhibit individual characteristics.
When the crystalline polyester (C) and the amorphous polyester are present in a phase-separated state, the crystalline polyester (C) and the amorphous polyester each effectively express the individual characteristics described above. Can do.

Whether or not the crystalline polyester (C) and the amorphous polyester are present in a phase-separated state in the toner can be confirmed by any of the following methods.
(1) The presence or absence of the formation of a phase-separated domain structure can be confirmed by measuring the endothermic peak due to the first temperature increase of the DSC of the toner. In the DSC endothermic peak measurement, there are at least the endothermic peaks (A) and (C) attributed to the amorphous polyester (A) and the crystalline polyester (C), respectively, which are attributed to the amorphous polyester (A). Endothermic peak (A) has a peak top in the range of 40 to 70 ° C., and endothermic peak (C) attributed to crystalline polyester (C) has a peak top in the range of 80 to 140 ° C. It is.

(2) The presence or absence of the formation of a phase separation structure can be confirmed by X-ray diffraction pattern measurement using a toner powder X-ray diffractometer. This is because, in the case of the toner of the present invention, the crystalline polyester (C) is present in the toner in a state of being phase-separated from the amorphous polyesters (A) and (B) while maintaining crystallinity. A diffraction peak attributed to the crystalline polyester (C) exists at a position of at least 2θ = 20 ° to 25 °.
When the phase-separated structure is not formed, the crystalline polyester (C) is compatible with the amorphous polyesters (A) and (B) without maintaining the crystalline structure of the crystalline polyester (C). The assigned diffraction peak does not appear.

  The toner of the present invention contains a fatty acid amide compound in a binder resin containing at least two types of amorphous polyesters (A) and (B) having different softening points and a crystalline polyester (C). In the toner, the softening point of the fatty acid amide compound Tm (Asp) and the softening point Tm (C) of the crystalline polyester (C) satisfy the relationship of Tm (C) <Tm (Asp). It is preferable that at least a part of the fatty acid amide compound is contained inside the domain part of the crystalline polyester (C) described above.

When the amorphous polyester and the crystalline polyester (C) are mixed and melted by heating, the crystalline polyester (C) and the amorphous polyester interact with each other due to heat applied during melt-kneading. Therefore, the crystallinity of the crystalline polyester (C) is lost, and a compatible phenomenon is likely to occur. When both are compatible, the glass transition point derived from the amorphous polyester is lowered, and a thermal change occurs at a temperature lower than the glass transition point of the amorphous polyester, so that the toner blocking property is deteriorated and the crystalline property is deteriorated. The low temperature fixability obtained by the polyester (C) is also impaired.
As described above, the toner of the present invention contains the fatty acid amide compound having a softening point higher than that of the crystalline polyester (C) in the binder resin, so that the binder resin is heated and the whole melts. In this case, the fatty acid amide compound contained in the domain part of the crystalline polyester (C) serves as a nucleus for recrystallization of the crystalline polyester (C), and recrystallizes the crystalline polyester (C). And the crystalline polyester (C), the amorphous polyester, and (A) and (B) are phase-separated in the toner particles. Thereby, the thermal characteristic of each polyester resin can be expressed effectively. By individually expressing the characteristics of each resin, it is possible to obtain a toner having excellent low-temperature fixability and excellent hot offset resistance and blocking resistance.
That is, the amorphous polyesters (A) and (B) having a high softening point can provide heat-resistant storage stability and hot offset resistance of the toner, and the crystalline polyester (C) can fix sharp melt in a low temperature range. Sex can be obtained.

In the present embodiment, a compound represented by R ¹ —CO—NR ² R ³ is applied as the fatty acid amide compound. In the formula, R ₁ is an aliphatic hydrocarbon group having 10 to 30 carbon atoms, and R ₂ and R ₃ are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or an aryl group having 6 to 10 carbon atoms. Or an aralkyl group having 7 to 10 carbon atoms. Here, the alkyl group, aryl group, and aralkyl group of R ₂ and R ₃ may be substituted with a generally inactive substituent such as a fluorine atom, a chlorine atom, a cyano group, an alkoxy group, or an alkylthio group. However, it is more preferably unsubstituted.
Examples of preferred compounds include stearic acid amide, stearic acid methylamide, stearic acid diethylamide, stearic acid benzylamide, stearic acid phenylamide, behenic acid amide, behenic acid dimethylamide, myristic acid amide, palmitic acid amide and the like.
In the present invention, among the fatty acid amide compounds, alkylene bis fatty acid amide is particularly preferably used. The alkylene bis fatty acid amide is a compound represented by the following general formula (II).

（式中Ｒ_１、Ｒ_３は炭素数５〜２１のアルキル基またはアルケニル基、Ｒ_２は炭素数１〜２０のアルキレン基を示す。）

(Wherein R ₁ and R ₃ represent an alkyl group or alkenyl group having 5 to 21 carbon atoms, and R ₂ represents an alkylene group having 1 to 20 carbon atoms.)

Examples of the alkylene bis saturated fatty acid amide represented by the general formula (II) include methylene bis stearic acid amide, ethylene bis stearic acid amide, methylene bis palmitic acid amide, ethylene bis palmitic acid amide, methylene bis behenic acid amide, ethylene bis Examples include behenic acid amide, hexamethylene bisstearic acid amide, hexaethylene bispalmitic acid amide, and hexamethylene bisbehenic acid amide. Of these, ethylene bis stearamide is most preferred.
These fatty acid amide compound, a softening point Tm (Tsp) is at lower than the surface temperature T _H during use of the fixing member, a fixing member surface, can serve effectively as a release agent.

  Specific examples of alkylene bis fatty acid amide compounds that can be used in addition to the above include propylene bis stearic acid amide, butylene bis stearic acid amide, methylene bis oleic acid amide, ethylene bis oleic acid amide, propylene bis oleic acid amide, Butylene bis oleic acid amide, methylene bis lauric acid amide, ethylene bis lauric acid amide, propylene bis lauric acid amide, butylene bis lauric acid amide, methylene bis myristic acid amide, ethylene bis myristic acid amide, propylene bis myristic acid amide, butylene bis Myristic acid amide, Propylene bispalmitic acid amide, Butylene bispalmitic acid amide, Methylene bispalmitoleic acid amide, Ethylene bispalmitoleic acid amide, Propylene vinyl Palmitoleic acid amide, butylene bispalmitoleic acid amide, methylene bisarachidic acid amide, ethylene bisarachidic acid amide, propylene bisarachidic acid amide, butylene bisarachidic acid amide, methylene biseicosenoic acid amide, ethylene biseicosenoic acid Amide, Propylene biseicosenoic acid amide, Butylene biseicosenoic acid amide, Methylene bis behenic acid amide, Ethylene bis behenic acid amide, Propylene bis behenic acid amide, Butylene bis behenic acid amide, Methylene bis Mention may be made of alkylene bis fatty acid amide compounds of saturated or monovalent unsaturated fatty acids such as erucic acid amide, ethylene biserucic acid amide, propylene biserucic acid amide, butylene biserucic acid amide.

Further, the softening point of the fatty acid amide compound Tm (Asp), compared the temperature _{T H} of the fixing roller surface, satisfies the Tm (Asp) _{<T H.}
The fatty acid amide compound added to the toner of the present invention also has a function as a release agent. By the softening point of the fatty acid amide compound Tm (Asp) is higher than the softening point Tm (C) of the crystalline polyester (C), has a lower softening point than the temperature T _H of the fixing roller surface during fixing, When the toner constituent material is melt-kneaded, this fatty acid amide compound becomes the nucleus of recrystallization of the crystalline polyester (C), and when the toner is fixed on the transfer material in the fixing nip, The fatty acid amide compound is melted by the heat received from the fixing roller 12 and flows out of the toner particles, and can function as a release agent for maintaining releasability from the fixing roller 12.

Temperature T _H of the fixing member surface in the present invention, the temperature of the fixing roller 12 (see FIG. 1.) Surface in after 90kg paper (manufactured by Ricoh Company, Ltd.) was passing 10 minutes paper continuously in the image forming apparatus, the average value of those measured 1 minute and the temperature T _H of the fixing member surface.

Hereinafter, other constituent materials used for the toner of the present invention will be described.
(Binder resin)
As the resin contained in the binder resin, any conventionally known resin can be used in addition to the polyester resin. For example, styrene, α-methylstyrene, chlorostyrene, styrene-propylene copolymer, styrene-butadiene copolymer, styrene-vinyl chloride copolymer, styrene-vinyl acetate copolymer, styrene-maleic acid copolymer, Styrene resins such as styrene-acrylic acid ester copolymer, styrene-methacrylic acid ester copolymer, styrene-acrylonitrile-acrylic acid ester copolymer, polyester resin, vinyl chloride resin, rosin modified maleic acid resin, phenol resin, There are epoxy resins, polyethylene resins, polypropylene resins, ionomer resins, polyurethane resins, silicone resins, ketone resins, xylene resins, petroleum resins, hydrogenated petroleum resins, and the like. Of these, styrene resins and polyester resins containing an aromatic compound as a component are preferred.

(Coloring agent)
As the colorant, all known dyes and pigments can be used. For example, carbon black, nigrosine dye, iron black, naphthol yellow S, Hansa yellow (10G, 5G, G), cadmium yellow, yellow iron oxide, ocher , Yellow lead, titanium yellow, polyazo yellow, oil yellow, Hansa yellow (GR, A, RN, R), pigment yellow L, benzidine yellow (G, GR), permanent yellow (NCG), Vulcan fast yellow (5G, R), Tartrazine Lake, Quinoline Yellow Lake, Anthrazan Yellow BGL, Isoindolinone Yellow, Bengala, Red Dan, Lead Zhu, Cadmium Red, Cadmium Mercury Red, Antimon Zhu, Permanent Red 4R, Para Red, Phi Sayred, Parachlor Ortonito Aniline Red, Resol Fast Scarlet G, Brilliant Fast Scarlet, Brilliant Carmin Min BS, Permanent Red (F2R, F4R, FRL, FRLL, F4RH), Fast Scarlet VD, Belkan Fast Rubin B, Brilliant Scarlet G, Resol Rubin GX, Permanent Red F5R , Brilliant Carmine 6B, Pigment Scarlet 3B, Bordeaux 5B, Toluidine Maroon, Permanent Bordeaux F2K, Helio Bordeaux BL, Bordeaux 10B, Bon Maroon Light, Bon Maroon Medium, Eosin Lake, Rhodamine Lake B, Rhodamine Lake Y, Alizarin Lake, Thio Indigo Red B, Thioindigo Maroon, Oil Red, Quinacridone Red, Pyrazolone Red Polyazo Red, Chrome Vermillion, Benzidine Orange, Perinone Orange, Oil Orange, Cobalt Blue, Cerulean Blue, Alkaline Blue Lake, Peacock Blue Lake, Victoria Blue Lake, Metal Free Phthalocyanine Blue, Phthalocyanine Blue, Fast Sky Blue, Indanthrene Blue (RS, BC), indigo, ultramarine blue, bitumen, anthraquinone blue, fast violet B, methyl violet lake, cobalt purple, manganese purple, dioxane violet, anthraquinone violet, chrome green, zinc green, chromium oxide, pyridian, emerald green, pigment Green B, Naphthol Green B, Green Gold, Acid Green Lake, Malachite Green Lake, Lid Russian nin green, anthraquinone green, titanium oxide, zinc white, litbon and mixtures thereof can be used. The content of the colorant is usually 1 to 15% by weight, preferably 3 to 10% by weight, based on the toner.

  The colorant can also be used as a master batch combined with a resin. As the binder resin to be kneaded together with the production of the master batch or the master batch, a polymer of styrene such as polystyrene, poly-p-chlorostyrene, polyvinyl toluene or the like, or a copolymer of these and a vinyl compound, Polymethyl methacrylate, polybutyl methacrylate, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, polyester, epoxy resin, epoxy polyol resin, polyurethane, polyamide, polyvinyl butyral, polyacrylic acid resin, rosin, modified rosin, terpene resin, fat Aromatic or alicyclic hydrocarbon resins, aromatic petroleum resins, chlorinated paraffins, paraffin waxes and the like can be mentioned, and these can be used alone or in combination.

(Charge control agent)
Known charge control agents can be used, such as nigrosine dyes, triphenylmethane dyes, chromium-containing metal complex dyes, molybdate chelate pigments, rhodamine dyes, alkoxy amines, quaternary ammonium salts (fluorine-modified 4 Secondary ammonium salts or compounds, tungsten simple substances or compounds, fluorine activators, salicylic acid metal salts, and metal salts of salicylic acid derivatives. Specifically, Bontron 03 of a nigrosine dye, Bontron P-51 of a quaternary ammonium salt, Bontron S-34 of a metal-containing azo dye, E-82 of an oxynaphthoic acid metal complex, E-84 of a salicylic acid metal complex , Phenolic condensate E-89 (above, Orient Chemical Industries, Ltd.), quaternary ammonium salt molybdenum complex TP-302, TP-415 (above, Hodogaya Chemical Co., Ltd.), quaternary ammonium salt copy Charge PSY VP2038, copy blue PR of triphenylmethane derivative, copy charge of quaternary ammonium salt NEG VP2036, copy charge NX VP434 (manufactured by Hoechst), LRA-901, LR-147 which is a boron complex (Nippon Carlit) Manufactured), copper phthalocyanine, perylene, quinacridone, azo series Fee, a sulfonic acid group, a carboxyl group, and polymer compounds having a functional group such as quaternary ammonium salts.
The amount of the charge control agent used is determined by the type of binder resin, the presence or absence of additives used as necessary, and the toner production method including the dispersion method, and is not uniquely limited. Preferably, it is used in the range of 0.1 to 10 parts by weight with respect to 100 parts by weight of the binder resin. The range of 0.2 to 5 parts by weight is preferable. When the amount exceeds 10 parts by weight, the chargeability of the toner is too high, the effect of the charge control agent is reduced, the electrostatic attraction with the developing roller is increased, the flowability of the developer is lowered, and the image density is lowered. Invite.

(Release agent)
As the mold release agent, it is desirable to use at least one wax having a low melting point of 50 to 120 ° C. The low melting point wax effectively works as a release agent in the dispersion with the binder resin between the fixing roller and the toner interface. Shows effect on offset. Examples of such a wax component include the following. Examples of waxes and waxes include plant waxes such as carnauba wax, cotton wax, wood wax and rice wax, animal waxes such as beeswax and lanolin, mineral waxes such as ozokerite and cercin, and paraffin, microcrystalline, And petroleum waxes such as petrolatum. In addition to these natural waxes, synthetic hydrocarbon waxes such as Fischer-Tropsch wax and polyethylene wax, and synthetic waxes such as esters, ketones, and ethers can be used. Furthermore, fatty acid amides such as 12-hydroxystearic acid amide, stearic acid amide, phthalic anhydride imide, chlorinated hydrocarbon, and low molecular weight crystalline polymer resin, poly-n-stearyl methacrylate, poly-n- A crystalline polymer having a long alkyl group in the side chain such as a homopolymer or copolymer of polyacrylate such as lauryl methacrylate (for example, a copolymer of n-stearyl acrylate-ethyl methacrylate, etc.) can also be used. .
The charge control agent and the release agent can be melt-kneaded together with the master batch and the binder resin, and of course, they may be added when dissolved and dispersed in the organic solvent.

The toner of the present invention is preferably a pulverized toner obtained by a kneading and pulverizing method. For example, after a binder resin, a colorant, and the like are uniformly mixed with a mixer such as a ball mill, a sealed kneader or a uniaxial or biaxial It can be produced by melt-kneading with an extruder or the like, cooling, pulverizing and classifying.
It may be produced by a polymerization method.
Furthermore, a fluidity improver or the like may be added to the toner surface as necessary. In this case, a mixer such as a super mixer or a Henschel mixer is used.

  The toner obtained as described above preferably has a weight average particle diameter (D4) of 3 to 13 μm. When the weight average particle size is smaller than 3 μm, the two-component developer is used as a one-component developer because the toner is fused to the surface of the magnetic carrier during a long period of stirring in the developing device, and the charging ability of the magnetic carrier is lowered. In this case, filming of the toner on the developing roller and fusion of the toner to a member such as a blade for thinning the toner are likely to occur. On the contrary, when the weight average particle diameter is larger than 13 μm, it becomes difficult to obtain a high-resolution and high-quality image, and when the balance of the toner in the developer is performed, the particle diameter of the toner In many cases, the fluctuation becomes large.

In addition, the ratio G′100 / G′150 of the storage elastic modulus G′100 at 100 ° C. and the storage elastic modulus G′150 at 150 ° C. of the amorphous polyester (B) is 3.0 to 30.0. Preferably there is.
The storage elastic modulus G ′ is an index indicating the elasticity of the toner. When the ratio G′100 / G′150 of the storage elastic modulus G ′ at 100 ° C. and the value at 150 ° C. is within the above range, the amorphous polyester ( The elasticity of B) does not fluctuate greatly, and a toner having stable fixing properties in a high temperature region can be obtained.

The storage elastic modulus G ′ was measured using a viscoelastic property apparatus (rheometer) RDAII type (manufactured by Rheometric Scientific). Samples were prepared by molding toner into pellets having a diameter of 20 mm and a thickness of 2.00 mm, and this was fixed to a 20 mmφ parallel plate using a HAAKE RheoStress RS50.
The measurement was performed under the conditions of temperature insertion, frequency 1 Hz (6.28 rad / s), temperature 80 to 210 ° C., strain 0.1 (strain control), and heating rate 2.5 ° C./Min.

The toner of the present invention preferably has a glass transition point (Tg) in the range of 35 to 70 ° C.
When the glass transition point is less than 35 ° C., hot offset resistance and heat-resistant storage stability deteriorate, and when it is 70 ° C. or more, low-temperature fixability deteriorates.

The glass transition point (Tg) was measured using a TG-DSC system TAS-100 manufactured by Rigaku Corporation. First, about 10 mg of a sample is placed in an aluminum sample container, which is placed on a holder unit and set in an electric furnace.
After heating from room temperature to 150 ° C. at a rate of temperature increase of 10 ° C./min, let stand at 150 ° C. for 10 minutes, cool the sample to room temperature and leave it for 10 minutes, then increase the rate of temperature to 150 ° C. again under a nitrogen atmosphere at 10 ° C./min DSC measurement was performed by heating at
The glass transition point (Tg) was calculated from the tangent of the endothermic curve near the Tg and the base line using the analysis system in the TAS-100 system.

(Average circularity)
The toner of the present invention preferably has an average circularity of 0.85 to 0.95. Average circularity SR = (peripheral length of circle having the same area as the projected particle area / perimeter length of projected particle image) × 100%. The closer the toner is to a true sphere, the closer to 100%. Toner having a high degree of circularity is easily affected by the developing electric field, and is developed faithfully along the electric field of the electrostatic latent image.
Thereby, a high-definition image with an appropriate image density can be formed with good reproducibility.
If the average circularity is greater than 0.95, it is close to a true sphere, so that the contact with the cleaning member deteriorates, resulting in poor cleaning. If the average circularity is less than 0.85, it is difficult to obtain satisfactory transferability and high-quality images free from dust.

  In the present invention, a flow type particle image analyzer (“FPIA-2100”; manufactured by Sysmex Corporation) is used for measurement of ultrafine toner, and analysis is performed using analysis software (FPIA-2100 Data Processing Program for FPIA version 00-10). Went. Specifically, 0.1 to 0.5 ml of 10 wt% surfactant (alkylbenzene sulfonate Neogen SC-A; Daiichi Kogyo Seiyaku) is added to a glass 100 ml beaker, and each toner 0.1 to 0 is added. 0.5 g was added and stirred with a microspatel, and then 80 ml of ion-exchanged water was added. The obtained dispersion was subjected to a dispersion treatment for 3 minutes with an ultrasonic disperser (manufactured by Honda Electronics Co., Ltd.). The shape and distribution of the toner were measured using the FPIA-2100 until the density of the dispersion was 5000 to 15000 / μl. In this measurement method, it is important that the concentration of the dispersion liquid is 5000 to 15000 / μl from the viewpoint of measurement reproducibility of the average circularity. In order to obtain the dispersion concentration, it is necessary to change the conditions of the dispersion, that is, the amount of surfactant to be added and the amount of toner. The amount of the surfactant varies depending on the hydrophobicity of the toner as in the measurement of the toner particle diameter described above. If it is added in a large amount, noise due to bubbles is generated. If the amount is small, the toner cannot be sufficiently wetted. It becomes insufficient. Further, the amount of toner added varies depending on the particle size, and it is small for small particle sizes and needs to be increased for large particle sizes. By adding 5 g, the dispersion concentration can be adjusted to 5000 to 15000 / μl.

(Volume average particle diameter)
The volume average particle diameter (Dv) of the toner of the present invention is preferably 3 to 13 μm, and the ratio (Dv / Dn) to the number average particle diameter (Dn) is in the range of 1.00 to 1.40. It is preferable that it exists in. Further, (Dv / Dn) is more preferably in the range of 1.00 to 1.25. By defining Dv / Dn in this way, it is possible to obtain a toner with high resolution and high image quality. In order to obtain a higher quality image, it is preferable to set Dv to 3 to 11 μm, Dv / Dn to 1.00 to 1.20, and particles of 3 μm or less to 1 to 10 in number%. More preferably, Dv is 3 to 10 μm and Dv / Dn is 1.00 to 1.15. Such a toner is excellent in all of heat-resistant storage stability, low-temperature fixability, and hot offset resistance, and particularly excellent in image gloss when used in a full-color copying machine. Even if the toner balance is extended over a long period, the toner particle size fluctuations in the developer are reduced, and good and stable developability can be obtained even with long-term stirring in the developing device.

The volume average particle diameter and the particle size distribution of the toner can be measured using, for example, a toner particle size distribution measuring apparatus by a Coulter counter method. Examples of the measuring device include Coulter Counter TA-II and Coulter Multisizer II (both manufactured by Coulter). Measurement was performed by connecting an interface (manufactured by Nichiken Giken Co., Ltd.) for outputting the number distribution and volume distribution to a PC9801 personal computer (manufactured by NEC).
Hereinafter, a method for measuring the toner particle diameter using this measuring apparatus will be described. First, 0.1 to 5 ml of a surfactant (preferably alkylbenzene sulfonate) is added as a dispersant to 100 to 150 ml of an aqueous electrolytic solution. Here, the electrolytic solution is a solution prepared by preparing a 1% NaCl aqueous solution using primary sodium chloride. For example, ISOTON-II (manufactured by Coulter) can be used. Here, 2 to 20 mg of a measurement sample is further added. The electrolytic solution in which the sample is suspended is subjected to a dispersion treatment with an ultrasonic disperser for about 1 to 3 minutes, and the measuring device is used to measure the volume and number of toner particles or toner using a 100 [μm] aperture. Then, the volume distribution and the number distribution are calculated. From the obtained distribution, the volume average particle diameter (Dv) and the number average particle diameter (Dn) of the toner can be obtained. As a channel, it is less than 2.00-2.52 [micrometer]; 2.52-less than 3.17 [micrometer]; 3.17-less than 4.00 [micrometer]; 4.00-5.04 [micrometer] Less than 5.04 to 6.35 [μm]; 6.35 to less than 8.00 [μm]; 8.00 to less than 10.08 [μm]; 10.08 to less than 12.70 [μm]; 12.70 to less than 16.00 [μm]; 16.00 to less than 20.20 [μm]; 20.20 to less than 25.40 [μm]; 25.40 to less than 32.00 [μm]; Using 13 channels of 00 to less than 40.30 [μm], particles having a particle size of 2.00 [μm] or more to less than 40.30 [μm] were targeted.

(Shape factors SF-1 and SF-2)
The toner of the present invention is preferably a toner having a shape factor SF-1 in the range of 100 to 180 and SF-2 in the range of 100 to 180. SF-1 is more preferably 110 to 170, more preferably 120 to 160, and particularly preferably 130 to 150. SF-2 is more preferably 110 to 170, more preferably 120 to 160, and particularly preferably 130 to 150.
The shape factors SF-1 and SF-2 are represented by the following formulas (3) and (4) as described above.
SF-1 = {(MXLNG) ² / AREA} × (100π / 4) Expression (3)
SF-2 = {(PERI) ² / AREA} × (100π / 4) Expression (4)
When the value of SF-1 is 100, the shape of the toner becomes a true sphere, and becomes larger as the value of SF-1 increases. Further, when the value of SF-2 is 100, unevenness does not exist on the toner surface, and as the value of SF-2 increases, the unevenness of the toner surface becomes more prominent.
The shape factor SF-1 is 100 images of toner particles magnified by a magnification of 500 using an electron microscope (for example, FE-SEM (S-800) manufactured by Hitachi, Ltd., and the same applies hereinafter). The image information is sampled randomly, and the image information can be obtained through an interface by an image analysis device (for example, Nexus NEW CUVER ver. It is a value obtained by introducing into and analyzing and calculating from Equation (3).
The shape factor SF-2 is obtained by randomly sampling 50 toner particle images magnified to a magnification of 3500 times using an electron microscope, introducing the image information into an image analysis apparatus via an interface, and performing analysis. It is a value obtained from 4).

  When the shape factors SF-1 and SF-2 are both close to 100 and the shape of the toner is close to a true sphere, the contact between the toner and the toner or the toner and the image carrier becomes a point contact. Accordingly, the fluidity is increased and the adhesion between the toner and the image carrier is also weakened, and the transfer rate is increased. The dot reproducibility is also improved. On the other hand, when the toner shape factors SF-1 and SF-2 are large to some extent, the margin for cleaning increases, and there is no problem such as defective cleaning. Therefore, it is preferable that the shape factors SF-1 and SF-2 are in the range of 100 to 180 as a range in which the image quality is not deteriorated from the balance between the two.

The toner of the present invention can be used as a two-component developer in combination with a magnetic carrier. The carrier to toner content ratio in the developer is preferably 0.5 to 10.0 parts by weight of toner with respect to 100 parts by weight of carrier. As the carrier, any conventionally known magnetic oxide can be used. Conventionally known materials such as iron powder, ferrite powder, magnetite powder, and magnetic resin carrier having a particle diameter of 50 to 125 μm can be used. In particular, ferrite and magnetite having grain boundaries and vacancies on the surface of the core material are preferable, and a mixture thereof may be used. As the ferrite, Ni—Zn ferrite, Cu—Zn ferrite, Mn ferrite, Mg ferrite, and Mn—Mg ferrite are more preferable. Examples of the coating material include amino resins such as urea-formaldehyde resin, melamine resin, benzoguanamine resin, urea resin, polyamide resin, and epoxy resin. Polyvinyl and polyvinylidene resins such as acrylic resins, polymethyl methacrylate resins, polyacrylonitrile resins, polyvinyl acetate resins, polyvinyl alcohol resins, polyvinyl butyral resins, polystyrene resins and styrene acrylic copolymer resins, Halogenated olefin resins such as vinyl, polyester resins such as polyethylene terephthalate resin and polybutylene terephthalate resin, polycarbonate resins, polyethylene resins, polyvinyl fluoride resins, polyvinylidene fluoride resins, polytrifluoroethylene resins, polyhexafluoro Propylene resin, copolymer of vinylidene fluoride and acrylic monomer, copolymer of vinylidene fluoride and vinyl fluoride, tetrafluoroethylene and vinylidene fluoride and non- Monomers including a fluoro terpolymers such, and silicone resins. Moreover, you may contain electrically conductive powder etc. in coating resin as needed. As the conductive powder, metal powder, carbon black, titanium oxide, tin oxide, zinc oxide and the like can be used, and carbon black is particularly preferable. As the carbon black, furnace black, acetylene black, thermal black and the like can be used. These conductive powders preferably have an average particle diameter of 1 μm or less. When the average particle diameter is larger than 1 μm, it becomes difficult to control electric resistance.
The toner of the present invention can also be used as a one-component developer by using it as a magnetic toner containing a magnetic material. In this case, the magnetic material contained in the toner includes iron oxides such as magnetite, hematite, and ferrite, metals such as iron, cobalt, and nickel, or aluminum of these metals, cobalt, copper, lead, magnesium, tin, zinc, Examples include alloys of metals such as antimony, beryllium, bismuth, cadmium, calcium, manganese, selenium, titanium, tungsten, vanadium, and mixtures thereof. Magnetite is particularly preferable from the viewpoint of magnetic properties.

The image forming apparatus of the present invention to which the above toner is applied will be described below.
FIG. 1 shows an image forming apparatus according to the present invention, specifically a schematic configuration of a laser beam printer. A photoconductor 3 as an image carrier is provided at the upper right of the image forming apparatus 1 main body in the drawing, and a charging device 4, a developing device 8, and a cleaning device 20 are provided around the photoconductor 3. Yes. Above the photoconductor 3, an exposure device 30 is provided that exposes the photoconductor 3 with laser light based on image information to form a latent image.
The exposure apparatus 30 is provided with a rotating polygon mirror 5, and a light source 6 for outputting a laser beam to the rotating polygon mirror 5 is provided on the right side of the rotating polygon mirror 5. The light source 6 is constituted by a semiconductor laser, a light emitting diode, or the like. Between the rotary polygon mirror 5 and the light source 6, an fθ lens 7 for passing light reflected by the rotary polygon mirror 5 is provided.
Further, a transfer device 12 for transferring the toner image on the photoconductor 3 onto a transfer material is provided between the developing device 8 and the cleaning device 20, and on the left side of the transfer device 12 in the drawing, A fixing device 2 for fixing the toner image on the transfer material is provided.
In the fixing device 2, a heating roller 14 having a heater lamp 25 and a pressure roller 15 are provided to face each other, and the heating roller 14 and the pressure roller 15 constitute a fixing roller 21.
A sheet hopper 9 for storing a transfer material 10 as a fixing medium is provided at the lower part of the image forming apparatus 1. Above the sheet hopper 9, the transfer material stacked on the sheet hopper 9 is provided. A paper transport tractor 11 for transporting 10 is provided. In addition, a buffer plate 24 is provided between the paper transport tractor 11 and the fixing device 2 to absorb slack and sticking generated on the transfer material 10.

The developing device 8 includes a developing unit 81 and a toner supply chamber 82 for supplying toner to the developing unit 81. The developing unit 81 is provided with a developer carrying member 8a for carrying the developer and supplying it to the photosensitive member 3, and in the vicinity of the developer carrying member 8a, the developing on the developer carrying member 8a is performed. A developer regulating member 8c that regulates the amount of the agent is provided in contact with the developer carrier 8a.
The developer carrier 8a is formed of a conductive, non-magnetic hollow cylindrical member, is rotatably supported by the developing device 8 body, and is provided at a minute interval from the photoreceptor 3. A magnet roll fixed coaxially with the developer carrier 8a is provided inside the developer carrier 8a, and the developer in the toner supply chamber 82 is supported by the developer by the magnetic force of the magnet roll. It is magnetically attracted to the outer peripheral surface of the body 8a and conveyed to the development area. A power source (not shown) for applying a developing bias is connected to the developer carrier 8a. When a voltage is applied from this power source, a development between the developer carrier 8a and the photoreceptor 3 is developed. An electric field is formed in the region.

Hereinafter, the operation of the image forming apparatus 1 will be described.
In FIG. 1, when a printing operation start signal is transmitted from a controller (not shown), the photosensitive drum 3 starts to rotate in the arrow direction. The photoreceptor 3 rotates at a speed suitable for the printing speed set for the image forming apparatus 1 and continues this rotation until the printing operation is completed.
After the rotation of the photosensitive member 3 is started, a high voltage is applied to the corona charger of the charging device 4. The corona charger applies, for example, a positive charge to the surface of the photoconductor 3 to uniformly charge the surface of the photoconductor 3.

  The rotary polygon mirror 5 starts rotating immediately when the image forming apparatus main body 1 is powered on. The rotary polygon mirror 5 maintains its rotation at a constant speed with high accuracy while the power is turned on, and reflects the laser beam output from the light source 6 toward the fθ lens 7. The laser beam that has passed through the fθ lens 7 is irradiated while scanning the photosensitive drum 3.

After the character data or graphic data of the document is converted into a dot image, the dot image is further converted as a laser beam on / off signal and transmitted to the image forming apparatus 1 by a controller (not shown).
Based on this signal information, the charging device 4 and the exposure device 30 form a laser beam irradiated portion and a non-irradiated portion on the surface of the photosensitive drum 3 by the above-described operation, thereby forming a so-called electrostatic latent image. Form.

On the other hand, the developer carrying member 8a magnetically attracts the toner in the developing unit 81 by the magnetic force of the magnet roll while rotating at a predetermined speed, and transports it to the developing region.
When the electrostatic latent image forming area on the surface of the photosensitive drum 3 reaches the developing area T which is a position facing the developing device 8 by the rotation of the photosensitive drum 3, the action of the electric field formed in the developing area by the voltage applied from the power source. Thus, for example, a positively charged toner charged to a positive charge is electrostatically attracted to a portion of the latent image forming region where the charge has been lost by laser beam irradiation, and the toner is supplied to the electrostatic latent image. As a result, a toner image is formed on the surface of the photosensitive drum 3.

The image forming apparatus of the present embodiment uses a two-component developer obtained by mixing the carrier and the above-described toner in the developing device 8. Furthermore, it is preferable that the carrier used in the developing device 8 has (a) a volume average particle diameter Dvc of 50 μm to 125 μm.
When the volume average particle diameter Dvc of the carrier is smaller than 50 μm, the magnetization per carrier grain becomes small, and the phenomenon of carrier adhesion tends to occur.
On the other hand, when the volume average particle diameter Dvc is larger than 125 μm, the ear formed by the developer becomes thick on the developing sleeve 8a as the developer carrying member, and the reproducibility of a sharp image is lowered. Further, since the specific surface area of the carrier particles is small, the ability to impart charge to the toner becomes insufficient, and problems due to poor charging such as background fogging occur, which is not preferable.

The carrier used in the developing device 8 has a particle size distribution in which (b) a carrier having a particle size of less than 0.4 Dvc is 0.1% by weight or less, and (c) 0.4 Dvc or more and 0.6 Dvc. It is preferable that a carrier having a particle size of less than has a particle size distribution of 4.0% by weight or less.
The carrier located in the particle size distribution of less than 0.4 Dvc with respect to the volume average particle diameter Dvc of the carrier is present in an amount exceeding 0.1 wt% with respect to the total weight of the carrier, or 0.4 Dvc or more and 0. If the carrier located in the particle size distribution of less than 6 Dvc is present in an amount exceeding 4.0% by weight with respect to the total weight of the carrier, a carrier with extremely weak magnetization is present on the developer carrier 8a. Even if the entire volume average particle diameter is within the above range, it is difficult to prevent carrier adhesion.
By using the carrier having the above particle size distribution in the image forming apparatus, it is possible to prevent carrier adhesion.
In the present embodiment, 0.4Dvc and 0.6Dvc indicate a certain particle size range obtained by multiplying a predetermined ratio value with the particle size range of the carrier volume average particle size Dvc. is there.

The volume average particle diameter Dvc of the carrier used in the present invention can be measured using an SRA type measuring instrument of a Microtrac particle size distribution meter (manufactured by Nikkiso Co., Ltd.).
Specifically, what was performed by the range setting of 0.7 micrometer or more and 125 micrometers or less was used. Further, methanol was used for the dispersion, and the refractive index was set to 1.33 and the refractive indexes of the carrier and the core material were set to 2.42.

In general, when the linear velocity Va of the developer carrying member 8a is set at a high speed of Va> 650 mm / sec, the impact when the magnetic brush formed on the developer carrying member 8a contacts the photosensitive member 3 is large. Thus, the carrier constituting the magnetic brush is easily separated from the magnetic brush, and therefore, the carrier adhesion is more likely to occur than when the image forming operation is performed with the linear velocity of the developer carrier 8a being reduced. When carrier adhesion occurs on the photoreceptor 3, stains and image defects on the image are generated to deteriorate the image quality, and the surface of the photoreceptor 3 is worn due to adhesion of the carrier onto the photoreceptor 3. The durability of the photoreceptor 3 and the carrier is lowered.
However, the image forming apparatus of the present invention uses the carrier having the above-mentioned specific volume average particle diameter and particle size distribution, so that even if the linear velocity of the developer carrying member 8a is Va> 650 mm / second, the carrier is attached. It is possible to provide a high-quality image without occurrence of abnormal images.

In the toner used in the image forming apparatus of the present invention, as described in detail above, the crystalline polyester (C) and the amorphous polyester are present in a state of being phase-separated from each other. For this reason, the toner heated at the fixing nip portion of the fixing roller 21 is quickly fixed on the transfer material 10 due to the sharp melt property of the crystalline polyester (C), and further the fatty acid amide contained in the toner particles. It is quickly released from the surface of the heating roller 14 by the compound and other release agents.
For this reason, as the linear velocity Va of the developer carrier 8a is improved, even when the linear velocity of the fixing roller 120 is increased, the fixing property at the fixing nip portion is maintained and the occurrence of hot offset is suppressed. Even when an image is formed at a high speed, an abnormal image does not occur, and a fixed image with good fixability can be obtained.

  In the present invention, the linear velocity Va of the developer carrier 8a is closest to the photosensitive member 3 in the developing sleeve as the developer carrier 8a using a linear velocity measuring device RP704Z / FG-1200 (Ono Sokki). The measured linear velocity is obtained by bringing the measuring instrument into direct contact with the sleeve.

When the portion where the toner image is formed on the photosensitive drum 3 reaches the transfer position T formed by the photosensitive drum 3 and the transfer device 12, the paper transport tractor 11 is stored in the paper hopper 9 in synchronization with this arrival timing. The continuous paper 10 being conveyed is conveyed toward the transfer position T.
The transfer device 12 applies a charge having a polarity opposite to that of the toner image to the back side of the transfer material 10 that has been transported to the transfer position T, so that the toner image formed on the photosensitive drum 3 is transferred onto the transfer material 10. The toner image is transferred onto the transfer material 10 by suction. The cleaning device 20 removes residual toner, adhered matter, and the like existing on the surface area of the photosensitive drum 3 that has passed the transfer position T, and prepares for the next image forming operation.
The paper transport tractor 11 transports the transfer material 10 that has passed the transfer position T to the fixing device 2 via the buffer plate 24. The buffer plate 24 absorbs slack and sticking that occurs on the transfer material 10 when a difference occurs between the conveyance speed of the paper conveyance tractor 11 and the conveyance speed of the fixing roller 21, so that the transfer material 10 is appropriately conveyed. Maintain state.

  The fixing device 2 preheats the transfer material 10 with the preheating plate 13, and then sandwiches and conveys the transfer material 10 while heating and pressing the transfer material 10 at the nip portion formed by the heating roller 14 and the pressure roller 15. The toner image transferred above is melted and fixed.

The paper feed roller 16 sends the transfer material 10 sent by the heating roller 14 and the pressure roller 15 to the scatter table 19 side.
The transfer material 10 sent to the scatter table 19 is alternately folded along the perforation provided in the transfer material 10 by the swinging motion of the swing fin 17, and then folded by the rotation operation of the paddle 18. It is loaded on the stacker table 19 while the state is adjusted.

  EXAMPLES The present invention will be further described below with reference to examples, but the present invention is not limited thereto. In the following, “part” means part by weight, and “%” means weight%.

<Production of amorphous polyesters A1 to A2>
Polyesters A1 and A2 have a composition (acid component, alcohol component) shown in Table 1 and hydroquinone of 0.1% by weight of the total amount of composition, a thermometer, a stirrer, a condenser, and a capacity of 5 L equipped with a nitrogen gas introduction pipe. In a four-necked round-bottomed flask, set the flask in a mantle heater, introduce nitrogen gas from a nitrogen gas inlet tube and keep the flask in an inert atmosphere, and keep the temperature at 160 ° C. For 5 hours and then at 200 ° C. for 1 hour, and then reacted at 8.3 kPa for 1 hour to obtain each polyester.

  Table 1 shows the raw materials and softening point Tm (° C.) of the amorphous polyesters A1 to A2 used in Examples and Comparative Examples.

<Manufacture of amorphous polyester B1-B2>
Polyesters B1 and B2 are composed of the composition shown in Table 1 (acid component, alcohol component) and hydroquinone of 0.1% by weight of the total amount of composition, a thermometer, a stirrer, a condenser, and a capacity of 5 L equipped with a nitrogen gas introduction pipe. In a four-necked round-bottomed flask, set the flask in a mantle heater, introduce nitrogen gas from a nitrogen gas inlet tube and keep the flask in an inert atmosphere, and keep the temperature at 160 ° C. For 5 hours and then at 200 ° C. for 1 hour, and then reacted at 8.3 kPa for 1 hour to obtain each polyester.

  Table 2 shows the raw materials and softening point Tm (° C.) of the amorphous polyesters B1 and B2 used in the examples and comparative examples.

<Production of crystalline polyesters C1 to C3>
Put in a 5-liter four-necked flask, set a thermocouple, stirrer, condenser, blow nitrogen gas from the nitrogen inlet tube, add an appropriate amount of organic tin compound or inorganic tin compound as a catalyst, and at 200 ° C The reaction was carried out for 10 hours while removing water produced by dehydration condensation. Furthermore, it was made to react until the resin of the desired softening point was obtained at 8.0 kPa, and crystalline polyester C1-C3 was obtained.

  Table 3 shows the raw materials and the desired softening point temperature of the crystalline polyester (C) used in the present examples and comparative examples.

[Measurement method of softening point of polyester resin]
The softening points of the binder resin components A, B, and C were measured by the ring and ball method according to JISK2207.

Example 1
<Production example>
Toner prescription:
Amorphous polyester A1 55 parts by weight Amorphous polyester B1 20 parts by weight Crystalline polyester C1 25 parts by weight Carbon black (MOGUL L, manufactured by Cabot Corp.) 10 parts by weight Charge control agent (Nigrosine N-04 manufactured by Orient Chemical Industry Co., Ltd.) 2 parts by weight Carnauba wax (Carnauba wax C1, melting point 84 ° C., manufactured by Kato Yoko) 3 parts by weight Fatty acid amide (Kao wax EB-FF, melting point 141.5-146.5 ° C., manufactured by Kao Corporation) 5 parts by weight

After sufficiently mixing the above constituent materials with a Henschel mixer, using a co-rotating twin screw extruder, the roll rotation speed is 200 rotations / minute, the heating temperature in the roll is 100 ° C., and the supply rate of the mixture is 15 kg / hour. It adjusted and melt-kneaded. The obtained melt-kneaded product was rolled to a thickness of 3 mm using a rolling roll, cooled, coarsely pulverized, and then pulverized and classified by a turbo mill to obtain a powder having a volume average particle diameter of 10.0 μm.
To 100 parts by weight of the obtained powder, 1.0 part by weight of hydrophobic silica TG820 (manufactured by Cabot) was added as an external additive and mixed with a Henschel mixer to obtain a toner. Table 4 shows the toner materials used in the production of each toner.

(Example 2)
A toner was obtained in the same manner as in Example 1 except that 3 parts by weight of carnauba wax was changed to 3 parts by weight of polyethylene wax (LEL800, melting point 133 ° C., manufactured by Sanyo Chemical Industries). Table 4 shows the toner materials used.

(Example 3)
A toner was obtained in the same manner as in Example 1 except that the wax was changed from 3 parts by weight of carnauba wax to 2 parts by weight of carnauba wax and 2 parts by weight of polyethylene wax. Table 4 shows the toner materials used.

Example 4
Toner as in Example 1 except that the addition amount of amorphous polyester A1 was changed from 55 parts by weight to 65 parts by weight, and the addition amount of crystalline polyester C1 was changed from 25 parts by weight to 10 parts by weight. Got. Table 4 shows the toner materials used.

(Example 5)
Except that the addition amount of the amorphous polyester A1 was changed from 55 parts by weight to 70 parts by weight, and the addition amount of the amorphous polyester B1 was changed from 20 parts by weight to 10 parts by weight, the same as in Example 1. A toner was obtained. Table 4 shows the toner materials used.

(Comparative Example 1)
A toner was obtained in the same manner as in Example 1 except that the amorphous polyester A1 was changed to the amorphous polyester A2. Table 4 shows the toner materials used.

(Comparative Example 2)
A toner was obtained in the same manner as in Example 1 except that the amorphous polyester B1 was changed to the amorphous polyester B2. Table 4 shows the toner materials used.

(Comparative Example 3)
A toner was obtained in the same manner as in Example 1 except that the crystalline polyester C1 was changed to the crystalline polyester C2. Table 4 shows the toner materials used.

(Comparative Example 4)
A toner was obtained in the same manner as in Example 1 except that the crystalline polyester C1 was changed to the crystalline polyester C3. Table 4 shows the toner materials used.

(Comparative Example 5)
The fatty acid amide compound was changed from ethylene bis-stearic acid amide (Kaowax EB-FF; melting point 141.5 to 146.5 ° C., manufactured by Kao Corporation) to stearic acid amide (fatty acid amide T; melting point 97 to 102 ° C., manufactured by Kao Corporation). The toner was obtained in the same manner as in Example 1 except that the above was changed. Table 4 shows the toner materials used.

(Comparative Example 6)
A toner was obtained in the same manner as in Comparative Example 6 except that the fatty acid amide compound was not added.
Table 4 shows the toner materials used.

(Comparative Example 7)
The addition amount of the amorphous polyester B1 is changed from 20 parts by weight to 70 parts by weight, the addition amount of the crystalline polyester C1 is changed from 25 parts by weight to 30 parts by weight, and the amorphous polyester A is not added. In the same manner as in Example 1, a toner was obtained.
Table 4 shows the toner materials used.

(Comparative Example 8)
The addition amount of the amorphous polyester A1 was changed from 55 parts by weight to 80 parts by weight, the addition amount of the crystalline polyester C1 was changed from 25 parts by weight to 20 parts by weight, and the amorphous polyester B was not added. A toner was obtained in the same manner as in Example 1.
Table 4 shows the toner materials used.

(Comparative Example 9)
A toner was obtained in the same manner as in Comparative Example 8, except that 20 parts by weight of amorphous polyester B1 was added and crystalline polyester C was not added.
Table 4 shows the toner materials used.

The toner obtained above was evaluated for the following items.
(Evaluation item-1)
(1) Low temperature fixability (tape peelability)
4 parts by weight of toner and 96 parts by weight of carrier (volume average particle size DV100 μm, less than 0.4 Dvc, 0.0% by weight, 0.4 Dvc or more and less than 0.6 Dvc, 2.0% by weight) are mixed for 5 minutes with a tumbler mixer. Thus, a developer was obtained.
Next, the image forming apparatus 1 shown in FIG. 1 is modified so that an image can be formed on A4 paper and can be fixed outside the apparatus, and the developing device 8 is filled with a developer to reduce the toner adhesion amount to 0. An unfixed image of 2 cm × 12 cm was obtained by adjusting to 0.5 mg / cm ² . Further, the fixing roll 21 was kept at a temperature of 150 ° C., and an unfixed image was fixed at a linear speed of 1500 mm / sec. “RICOPY PPC paper TYPE6000” (manufactured by Ricoh Co., Ltd.) was used as the fixing paper.
A scotch tape (manufactured by Sumitomo 3M Co., Ltd.) is applied to the image obtained at each fixing temperature, and the tape is peeled off after being left for 3 hours and transferred to a blank sheet. The difference from the blank was 0.300 or more was evaluated as unfixed, and the low-temperature fixability was evaluated according to the following evaluation criteria.
[Evaluation criteria]
A: Difference from blank is less than 0.150 B: Difference from blank is 0.150 or more and less than 0.300 X: Difference from blank is 0.300 or more (2) Hot offset resistance 4 parts by weight of toner and carrier 96 parts by weight (volume average particle size DV100 μm, less than 0.4 Dvc, 0.0 wt%, 0.4 Dvc or more, less than 0.6 Dvc, 2.0 wt%) is mixed for 5 minutes with a tumbler mixer to obtain a developer. It was.
Next, the image forming apparatus shown in FIG. 1 is modified so that an image can be formed on A4 paper and can be fixed outside the apparatus, and the developing device 8 is filled with a developer, and the toner adhesion amount is 1.0 mg. An unfixed image of 2 cm × 12 cm was obtained by adjusting to be / cm ² .
Further, an unfixed image was fixed at a linear speed of 250 mm / second while the temperature of the fixing roll 21 was gradually increased from 100 ° C. to 250 ° C. by 5 ° C., and a fixing test was performed. “RICOPY PPC paper TYPE6000” (manufactured by Ricoh Co., Ltd.) was used as the fixing paper.
The presence or absence of hot offset on the fixing paper in the fixed image obtained at each fixing temperature was visually confirmed and evaluated.
[Evaluation criteria]
A: Hot offset generation is 250 ° C. or higher. O: Hot offset generation is 200 ° C. or higher and lower than 250 ° C. X: Hot offset generation is lower than 200 ° C. (3) Evaluation of blocking property 10 g of each of the toners produced in Examples and Comparative Examples It was put in a glass bottle with a volume of 100 ml and left in a constant temperature layer at a temperature of 50 ° C. for 1 day, and the state of the toner was observed and evaluated.
[Evaluation criteria]
◎: No blocking at all ○: Soft caking state ×: Hard caking state

  Table 5 shows the evaluation results of the toner.

As can be seen from Table 5, in Examples 1 to 5, the toner has excellent low-temperature fixability, hot offset resistance, and blocking resistance, and can be fixed in a short time in a low-temperature region. An abnormal image due to offset did not occur, and a stable image could be obtained even when used for a long time.
On the other hand, Comparative Examples 5 and 6 were inferior in blocking resistance and hot offset resistance.
In addition, Comparative Examples 1 to 4 are inferior in low-temperature fixability, and Comparative Examples 7 to 9 cannot sufficiently obtain low-temperature fixability or hot offset resistance. The result was inferior in either the heat resistant storage stability or the hot offset resistance.

  Next, carrier particles having a predetermined volume average particle size and particle size distribution were prepared by the production method described below. This carrier and each of the toners described above were mixed to obtain a two-component developer, and then the following evaluation items were evaluated.

(Carrier manufacturing method)
A fluorine-containing acrylic resin was diluted with toluene to prepare a dispersion liquid in which an aminosilane coupling agent was dispersed. After this adjustment liquid is heated, the surface of the core material having a volume average particle size of 95 μm is spray-coated using a fluidized coating apparatus, and then baked and cooled to obtain an average coated resin film thickness of 1. 0 μm carrier particles were obtained.
Further, the obtained carrier particles are sieved, and the particle size distribution is 0.0% by weight of less than 0.4 Dvc, 2.0% by weight of 0.4 Dv or more and less than 0.6 Dv, and the volume average particle diameter DV is 100 μm. Got a career.

(Example 6)
4 parts by weight of the toner used in Example 1 and 96 parts by weight of the carrier described above were mixed for 5 minutes with a tumbler mixer to obtain a two-component developer.
Table 6 shows the toner material used and the volume average particle diameter of the carrier.

(Example 7)
4 parts by weight of the toner used in Example 2 and 96 parts by weight of the carrier described above were mixed for 5 minutes with a tumbler mixer to obtain a two-component developer.
Table 6 shows the toner material used and the volume average particle diameter of the carrier.

(Example 8)
4 parts by weight of the toner used in Example 3 and 96 parts by weight of the carrier described above were mixed for 5 minutes with a tumbler mixer to obtain a two-component developer.
Table 6 shows the toner material used and the volume average particle diameter of the carrier.

Example 9
4 parts by weight of the toner used in Example 4 and 96 parts by weight of the carrier described above were mixed for 5 minutes with a tumbler mixer to obtain a two-component developer.
Table 6 shows the toner material used and the volume average particle diameter of the carrier.

(Example 10)
4 parts by weight of the toner used in Example 5 and 96 parts by weight of the carrier described above were mixed for 5 minutes with a tumbler mixer to obtain a two-component developer.

(Example 11)
In the above carrier production method, only the mesh of the sieve used for sieving is changed, and the particle size distribution is 0.5% by weight below 0.4 Dvc and 8.0% by weight below 0.4 Dv and below 0.6 Dv. I got a career. 96 parts by weight of this carrier and 4 parts by weight of the toner used in Example 1 were mixed for 5 minutes with a tumbler mixer to obtain a two-component developer.
Table 6 shows the volume average particle diameters of the toner material and the carrier.

(Example 12)
In the above carrier production method, only the sieve mesh used for sieving is changed, and the particle size distribution is less than 0.4 Dvc is 0.5 wt%, and 0.4 Dv or more and less than 0.6 Dv is 8.0 wt%. Got a career. 96 parts by weight of this carrier and 4 parts by weight of the toner used in Example 2 were mixed for 5 minutes with a tumbler mixer to obtain a two-component developer.
Table 6 shows the volume average particle diameters of the toner material and the carrier.

(Example 13)
In the above carrier production method, only the sieve mesh used for sieving is changed, and the particle size distribution is less than 0.4 Dvc is 0.5 wt%, and 0.4 Dv or more and less than 0.6 Dv is 8.0 wt%. Got a career. 96 parts by weight of this carrier and 4 parts by weight of the toner used in Example 3 were mixed for 5 minutes with a tumbler mixer to obtain a two-component developer.
Table 6 shows the volume average particle diameters of the toner material and the carrier.

(Example 14)
In the above carrier production method, only the sieve mesh used for sieving is changed, and the particle size distribution is less than 0.4 Dvc is 0.5 wt%, and 0.4 Dv or more and less than 0.6 Dv is 8.0 wt%. Got a career. 96 parts by weight of this carrier and 4 parts by weight of the toner used in Example 4 were mixed for 5 minutes with a tumbler mixer to obtain a two-component developer.
Table 6 shows the volume average particle diameters of the toner material and the carrier.

(Example 15)
In the above carrier production method, only the sieve mesh used for sieving is changed, and the particle size distribution is less than 0.4 Dvc is 0.5 wt%, and 0.4 Dv or more and less than 0.6 Dv is 8.0 wt%. Got a career. 96 parts by weight of this carrier and 4 parts by weight of the toner used in Example 5 were mixed for 5 minutes with a tumbler mixer to obtain a two-component developer.
Table 6 shows the volume average particle diameters of the toner material and the carrier.

(Example 16)
A fluorine-containing acrylic resin was diluted with toluene to prepare a dispersion liquid in which an aminosilane coupling agent was dispersed. After this adjustment liquid is heated, the surface of the core material having a volume average particle size of 35 μm is spray-coated using a fluid coating device, and then baked and cooled to obtain an average coated resin film thickness of 1. 0 μm carrier particles were obtained.
Further, the obtained carrier particles are sieved, and the particle size distribution is 0.0% by weight of less than 0.4 Dv, 2.0% by weight of 0.4 Dv or more and less than 0.6 Dv, and the volume average particle diameter DV is 35 μm. Got a career. 96 parts by weight of this carrier and 4 parts by weight of the toner used in Example 1 were mixed for 5 minutes with a tumbler mixer to obtain a two-component developer.
Table 6 shows the volume average particle size of the toner material and carrier used.

(Example 17)
A fluorine-containing acrylic resin was diluted with toluene to prepare a dispersion liquid in which an aminosilane coupling agent was dispersed. After this adjustment liquid is heated, spray coating is performed on the surface of the core material having a volume average particle diameter of 150 μm using a fluid coating apparatus, and then this is baked and cooled to obtain an average coating resin film thickness of 1. 0 μm carrier particles were obtained.
Further, the obtained carrier particles are sieved, and the particle size distribution is 0.0% by weight of less than 0.4 Dv, 2.0% by weight of 0.4 Dv or more and less than 0.6 Dv, and the volume average particle diameter DV is 150 μm. Got a career. 96 parts by weight of this carrier and 4 parts by weight of the toner used in Example 1 were mixed for 5 minutes with a tumbler mixer to obtain a two-component developer.
Table 6 shows the volume average particle diameters of the toner material and the carrier.

(Evaluation item-2)
Using the two-component developer obtained above, the following items were evaluated.
(1) Low temperature fixability (tape peelability)
Evaluation was performed in the same manner as in (Evaluation Item 1), except that the carrier used for the developer filled in the developing device 8 was changed to one having the volume average particle size and particle size distribution shown in Table 6.
(2) Hot offset resistance The same as (Evaluation Item 1), except that the carrier used for the developer filled in the developing device 8 is changed to one having the volume average particle size and particle size distribution shown in Table 6. And evaluated.
(3) Evaluation of blocking properties Evaluation was performed in the same manner as in (Evaluation item 1).
(4) Carrier Adhesion Evaluation Next, the image forming apparatus 1 shown in FIG. 1 is remodeled so that an image can be formed on A4 paper, the developing device 8 is filled with the developer, and the linear velocity of the developing sleeve 8a is increased. A printing test of 1000 sheets of solid images was performed at 1500 mm / second. As the fixing paper, “RICOPY PPC paper TYPE6000” (manufactured by Ricoh Co., Ltd.) was used.
The presence or absence of carrier adhesion in the obtained printed image was visually confirmed and evaluated.
[Evaluation criteria]
○: Carrier adhesion cannot be confirmed on image ×: Carrier adhesion can be confirmed on image (5) Halftone image quality evaluation 4 parts by weight of toner and 96 parts by weight of carrier are mixed for 5 minutes by a tumbler mixer and developed. An agent was obtained. Next, the image forming apparatus 1 shown in FIG. 1 is modified so that an image can be formed on A4 paper, and the developing device 8 is filled with the developer, and the linear velocity of the developing sleeve 8a is set to a linear velocity of 1500 mm / second. A printing test of 1 million halftone images was conducted. As the fixing paper, “RICOPY PPC paper TYPE6000” (manufactured by Ricoh Co., Ltd.) was used.
The presence or absence of uneven density of the halftone image in the obtained printed image was visually evaluated.
[Evaluation criteria]
A: There is no density unevenness and the halftone image reproducibility is particularly excellent. ○: There is little density unevenness and the halftone image reproducibility is excellent. X: There are many density unevenness and the halftone image reproducibility is poor.

  The evaluation results are shown in Table 7.

  As can be seen from Table 7, in Examples 6 to 17, the toner has excellent low-temperature fixability, hot offset resistance and blocking resistance, and can be fixed in a short time in a low-temperature region. An abnormal image due to offset did not occur, and a stable image could be obtained even in long-term use. Further, in Examples 6 to 10, an image having high reproducibility without image unevenness in a halftone image was obtained without generation of an abnormal image due to carrier adhesion even at the time of image formation at high speed.

1 is a schematic configuration diagram illustrating an example of an image forming apparatus according to the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 2 Fixing apparatus 13 Preheating board 14 Heating roller 15 Pressure roller 21 Fixing roller 3 Photoconductor 4 Charging apparatus 8 Developing apparatus 81 Developing unit 8a Developer carrier 82 Toner supply chamber 9 Paper hopper 10 Transfer material 11 Paper Transport tractor 12 Transfer device 16 Paper feed roller 17 Swing fin 19 Stacker table 20 Cleaning device 24 Buffer plate 30 Exposure device 5 Rotating polygon mirror 6 Light source 7 fθ lens T Transfer position

Claims (21)

In a toner that develops an electrostatic latent image on a latent image carrier, is transferred onto a transfer target, and is fixed by applying heat and / or pressure by a fixing member to form a toner image.
The toner contains at least a binder resin, a release agent, a colorant, and a fatty acid amide compound,
The binder resin comprises at least an amorphous polyester (A) having a softening point of 70 to 140 ° C., an amorphous polyester (B) having a softening point of 120 to 190 ° C., and a crystalline polyester (C). Have
Toner wherein the softening point TmC of the crystalline polyester (C), the temperature T _H of the fixing member surface, the softening point of the fatty acid amide compound Tm and (Asp), but characterized by satisfying the following formula (1).
_{TmC <Tm (Asp) <T} H ··· (1) The toner according to claim 1.
The crystalline polyester (C) forms a domain part in the toner. The toner according to claim 1 or 2,
At least a part of the fatty acid amide compound is contained in the domain part. The toner according to any one of claims 1 to 3,
The toner, wherein the softening point TmA of the amorphous polyester (A) and the softening point TmB of the amorphous polyester (B) satisfy a relationship of TmA <TmB-10 ° C. In the toner according to any one of claims 1 to 4,
A toner characterized in that the softening point TmA of the amorphous polyester (A) and the softening point TmC of the crystalline polyester (C) satisfy a relationship of TmC−40 ° C. ≦ TmA ≦ TmC. The toner according to any one of claims 1 to 5,
The crystalline polyester (C) has a softening point of 80 to 140 ° C. The toner according to any one of claims 1 to 5,
The ratio G′100 / G′150 of the storage elastic modulus G′100 at 100 ° C. and the storage elastic modulus G′150 at 150 ° C. of the amorphous polyester (B) is 3.0 to 30.0. Toner. The toner according to any one of claims 1 to 7,
The toner has a Tg in a range of 35 to 70 ° C. The toner according to any one of claims 1 to 8,
The toner according to claim 1, wherein the fatty acid amide compound is an alkylene bis fatty acid amide. The toner according to any one of claims 1 to 9,
The toner according to claim 1, wherein the fatty acid amide compound is ethylenebisstearic acid amide. The toner according to any one of claims 1 to 10,
The toner is produced by melt-kneading and then pulverizing. The toner according to any one of claims 1 to 11,
The release agent contains at least two kinds of waxes,
The toner according to claim 1, wherein at least one of the waxes is a hydrocarbon wax. The toner according to any one of claims 1 to 12,
The amorphous polyester (A) and / or the amorphous polyester (B) is produced using at least an inorganic tin compound or a compound containing titanium as a catalyst. The toner according to any one of claims 1 to 13,
The crystalline polyester (C) is produced using at least an inorganic tin compound or a compound containing titanium as a catalyst. The toner according to any one of claims 1 to 14,
The toner has an average circularity of 0.85 to 0.95. The toner according to any one of claims 1 to 15,
The toner has a volume average particle diameter of 3.0 to 13.0 μm and a ratio (Dv / Dn) of the volume average particle diameter (Dv) to the number average particle diameter (Dn) of 1.00 to 1.40. Toner characterized by being in range. The toner according to any one of claims 1 to 16,
The toner has a shape factor SF-1 in the range of 100 to 180 and a shape factor SF-2 in the range of 100 to 180.
Toner characterized by the above. The toner according to any one of claims 1 to 17,
The toner contains a magnetic substance. The toner according to any one of claims 1 to 17,
The toner is used by being mixed with a magnetic carrier coated with a resin. An image carrier that carries at least a latent image;
Development having a developer carrying member carrying and transporting a two-component developer containing toner and a carrier, and supplying the toner to the latent image on the image carrier by the developer carrying member to make a visible image Means,
Transfer means for transferring a visible image on the surface of the image carrier onto a fixing medium;
An image forming apparatus comprising: fixing means for fixing the visible image on the fixing medium by applying heat and / or pressure with a fixing member;
The toner used in the developing unit is the toner according to any one of claims 1 to 19,
The carrier used in the developing means is
(A) The volume average particle diameter Dvc is 50 μm to 125 μm,
(B) a carrier having a particle size of less than 0.4 Dvc has a particle size distribution of 0.1% by weight or less,
(C) An image forming apparatus, wherein a carrier having a particle size of 0.4 Dvc or more and less than 0.6 Dvc has a particle size distribution of 4.0% by weight or less.
_{TmC <Tm (Asp) <T} H ··· (1) The image forming apparatus according to claim 20, wherein
In the image forming apparatus, the linear velocity Va of the developer carrying member is set to Va> 650 mm / second.

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