JP2001305794A - Electrophotographic toner, electrophotographic developer and method for forming image - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide electrophotographic toner having excellent low temperature fixing properties, offset resistance, good release properties even for oil-less fixing and a wide fixing temperature range and to provide an electrophotograhpic toner excellent in smoothness of a fixed image which forms a stable image with high gloss. SOLUTION: The electrophotographic toner contains at least a binder resin, coloring agent and wax and contains internally added fine particles. The toner has a specified absolute value G* of complex elastic modulus and specified complex elastic modulus ΔG* (10%) and ΔG* (100%).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic toner used in an apparatus utilizing an electrophotographic process such as a copying machine and a printer, and more particularly to a color electrophotographic toner and an image forming method using the color toner. .

[0002]

2. Description of the Related Art As an electrophotographic process, Japanese Patent Publication No. 42-
Many methods have been known in the past, including the method described in JP-A-23910 and the like. In the electrophotographic process, a latent image is formed electrically on a photoreceptor using a photoconductive substance by various means, and the latent image is developed using toner.
After transferring the toner image to a transfer target such as paper with or without interposing the toner latent image on the photoreceptor through an intermediate transfer member, the transferred image is heated, pressurized, heated and pressurized, or solvent vapor or the like. This is a process of forming a fixed image through a plurality of steps of fixing. The toner remaining on the photoreceptor is cleaned by various methods as necessary, and the above-described plural steps are repeated.

[0003] In recent years, with the daily use of personal computers and the improvement of office network environments, the use of electrophotography is not only used as a copying machine but also as a printer for outputting electronic documents. Is progressing. Further, electronic documents handled by individuals are not limited to black-and-white character information, but include color documents, graphs, images, and the like, and color printers and color copiers have been widely used. With such changes in the office environment, printers and copiers have faithfully reproduced the original image, with good coloring and moderate gloss.
There is a demand for a high-quality color fixed image that does not look unnatural.

Further, in order to use color documents and the like as easily as conventional black-and-white documents, high-quality printing is performed on plain paper as well as on dedicated paper for color printers and color copiers. It is hoped that it can be done.

[0005] Further, with the rise of environmental awareness in recent years, it is strongly desired to save energy, and it is required to reduce power consumption during fixing as much as possible. Therefore, it is necessary that good fixing performance can be obtained even at a low fixing temperature. In order to make printers and copiers smaller and lighter, their components are actually as simple as possible.To obtain high-quality prints with excellent low-temperature fixability without using complicated structures Further, it is essential to further improve the performance of the toner.

As a general method of fixing a toner latent image on a transfer object such as paper, there is a heat compression method. This method is
This is to fix the toner latent image by passing the toner image on the transfer-receiving member under pressure into the surface of a fixing member having a surface formed of a material having releasability from the toner. In the case of this thermocompression bonding method, since the surface of the fixing member and the toner image on the transfer target body come into contact with each other under pressure,
The thermal efficiency is extremely good, and fixing can be performed quickly.

However, in the thermocompression bonding method, since the fixing member and the toner image come into pressure contact with each other in a heated and melted state,
If the fixing temperature is too high, the viscosity of the toner decreases, and a part of the toner image adheres and / or transfers to the surface of the fixing member, re-transfers to the next transfer target, and stains the transfer target. The "hot offset phenomenon" occurs. On the other hand, if the fixing temperature is too low, the toner does not melt sufficiently, so that the toner is not fixed on the transfer-receiving member, and a low-temperature offset phenomenon occurs. Therefore, it is desired to obtain a toner having good offset resistance and realizing low-temperature fixability. It is also desired to fix the surface of the fixing member without applying a release agent such as oil, as in the case of black and white printing, and the toner itself is required to have sufficient release properties.

The purpose of low-temperature fixing can be achieved by lowering the molecular weight and glass transition temperature of the binder resin, lowering the softening temperature of the toner, and lowering the minimum fixing temperature. However, this method deteriorates the storage stability of the toner and causes problems such as blocking. On the other hand, if the offset resistance is improved by increasing the elasticity of the binder resin by, for example, increasing the molecular weight distribution of the binder resin, the minimum fixing temperature tends to be higher.

In order to solve this problem, the viscoelastic behavior is controlled by focusing on the rheological properties of the toner.
Attempts to achieve both low-temperature fixability and offset resistance have been proposed.

For example, Japanese Patent Application Laid-Open No. 4-353866 discloses that the temperature at which the storage elastic modulus starts falling is in the range of 100 to 110 ° C., has a specific storage elastic modulus at 150 ° C., and has a peak loss elastic modulus. An electrophotographic toner having rheological properties of 125 ° C. or higher is disclosed. However, since the electrophotographic toner has a high temperature at which the storage elastic modulus starts falling and a high peak temperature of the loss elastic modulus, further improvement in low-temperature fixability is desired.

Japanese Patent Application Laid-Open No. 9-6051 discloses a toner for electrostatic charge development wherein the storage elastic modulus of a binder resin is within a specific range at 120 ° C. and the complex elastic modulus is within a specific range at 100 ° C. Has been disclosed. However, since the storage modulus at 120 ° C. is too high, improvement in low-temperature fixability is desired.

Further, not only the viscoelastic behavior of the binder resin is controlled but also an attempt has been made to control the viscoelastic behavior by adding an additive such as fine particles to the binder resin. For example, JP-A-7-77837 discloses a composition in which a binder resin has domain particles and a matrix having a particle size of 0.5 to 2 μm as main components, and a storage elastic modulus at 80 to 100 ° C. falls within a specific range. And a toner having a loss elastic modulus at 200 to 220 ° C. within a specific range. However, the toner described in this publication has a low storage elastic modulus at 80 to 100 ° C., and has insufficient releasability because it does not contain a low softening point substance as an essential component, which is problematic for use in oilless fixing. There is.

Japanese Patent Application Laid-Open No. 8-220800 discloses a toner for color electrophotography in which a plurality of colors are simultaneously fixed, wherein inorganic fine particles are internally added to the toner so that the viscoelastic characteristics are made uniform with other toners. Which discloses a toner for color electrophotography. However, according to this method, although the offset resistance is improved because only the fine particles are conventionally added to the toner to increase the elasticity, the minimum fixing temperature cannot be lowered, and further improvement in the low-temperature fixing property is desired.

When domain particles are present in the toner, the viscoelastic behavior changes depending on the magnitude of the distortion.
No. 7-295286. This publication discloses a magnetic toner containing at least a binder resin and a magnetic powder, and a magnetic developer containing a fluidizing agent and an inorganic fine powder.
By setting the rate of change of the storage elastic modulus G ′ and the loss elastic modulus G ″ at 0 ° C. and 1 to 50% strain to 50% or less, it can be applied to fixing from a low speed to a high speed and has excellent offset resistance. However, it discloses a method for obtaining a binder resin, but as described in the publication, the rate of change of G ′ and G ″ is suppressed to 50% or less, so that a binder resin is used. It is necessary to use a resin having a low molecular weight and a gel having a long crosslinking point distance. Further, when producing a toner, it is necessary to cut the gel to produce a high molecular weight having a long branched chain length. For this reason, the entanglement between the low molecular weight component and the high molecular weight component becomes strong, and tan δ becomes small, so that there is a problem that the smoothness of the image cannot be obtained and gloss does not occur.

In order to obtain excellent image quality as a color print, a toner having good color mixing and coloring properties is required. In particular, if the surface of the fixed image has irregularities, light is irregularly reflected, so that the glossiness (gloss) is lowered and the color developability is poor. Therefore,
It is desired that a fixed image having an appropriate gloss and having a small change in gloss even when the fixing temperature changes can be obtained.

As a method for obtaining a stable and high gloss by controlling the viscoelasticity, Japanese Patent Application Laid-Open No. Hei 8-179563 discloses that the storage viscoelastic modulus G 'at a frequency of 1000 Hz is 5%.
When the temperature at × 10 ⁴ dyn / cm ² is T ₁ ° C,
The storage elastic modulus G ′ at T ₁ + 20 ° C. is represented by A (dyn / c
when the m ^2), discloses a color toner for electrophotography A satisfies a specific formula. However, in this method, since A is too low, the offset resistance is not sufficient.

Japanese Patent Application Laid-Open No. 10-69116 discloses that
Disclosed are toners for developing electrostatic images having a storage elastic modulus in a specific range at 90 ° C. and 160 ° C. According to this method, good image smoothness can be obtained, but since the storage elastic modulus is too low, sufficient releasability for use in oilless fixing cannot be obtained, and offset resistance is also insufficient.

In general, when the storage elastic modulus is low, the viscosity of the toner becomes dominant, so that the toner easily transfers to the fixing member, and the offset resistance deteriorates. Conversely, if the storage elastic modulus is high, the toner loses its gloss because the toner elasticity recovers the shape of the toner after fixing and makes it easier to form irregularities on the surface. Therefore, it is extremely difficult to achieve both the offset resistance and the image smoothness.

[0019]

As described above, an electrophotographic toner which sufficiently satisfies the low-temperature fixing property, the peeling property and the anti-offset property and has good image surface smoothness has not yet been obtained. At present, a newly designed toner is desired.

Accordingly, an object of the present invention is to provide an electrophotographic toner which solves the above-mentioned problem, in particular, a color electrophotographic toner. SUMMARY OF THE INVENTION An object of the present invention is to provide an electrophotographic toner having excellent low-temperature fixability and anti-offset properties, having good releasability even in oilless fixing, and having a wide fixable temperature range. It is a further object of the present invention to provide an electrophotographic toner which is excellent in the smoothness of a fixed image and forms a stable and high gloss image.

[0021]

Means for Solving the Problems As a result of intensive studies, the present inventors have found that the above object can be achieved by effectively utilizing the fact that the viscoelastic behavior of toner changes due to distortion. That is, the inventors have found that the following problems can be solved by the following inventions <1> to <15>.

That is, <1> at least a binder resin and coloring
Containing fines and wax and no fine particles added internally
Electrophotographic toner, wherein the frequency of the binder resin is 10
rad / s, absolute value G of complex modulus at 10% strain
^*Is 1 × 10^FourThe temperature at which Pa becomes T₀(℃)
And the temperature T₀, Frequency 10rad / s, distortion 5%
Tan δ of the toner is 0.8 to 4.5,
Degree T₀, Frequency 10 rad / s, distortion 5%, 10% and
The complex elastic modulus of the toner at 100% is G ^*(5
%), G^*(10%) and G^*(100%),
ΔG represented by the following equation (1)^*(10%) is the following formula
ΔG that satisfies (2) and is represented by the following equation (3)^*(1
00%) satisfies the following formula (4),^*(5%) is 3
× 10^Four~ 5 × 10^FivePa and the temperature T₀+ 40 ° C, circumference
G at a wave number of 10 rad / s and a strain of 5% ^*(T₀+4
0.5%) is 1 × 10^Three~ 5 × 10^FiveIt is special that it is Pa
Electrophotographic toner.

ΔG ^* (10%) = | log (G ^* (10%) / G ^* (5%)) | / (log 10−log 5) Equation (1), ΔG ^* (10%) ≦ 2. 5φ + 0.1 Equation (2), ΔG ^* (100%) = | log (G ^* (100%) / G ^* (5%)) | / (log 100−log 5) Equation (3), ΔG ^* (100 %) ≧ 0.8φ Equation (4). In the formulas (2) and (4), φ indicates the volume fraction of the fine particles contained in the toner.

<2> In the electrophotographic toner according to <1>, it is preferable that the primary particle diameter of the fine particles is 500 nm or less and the volume fraction φ is 0.03 to 0.5. <3> In the electrophotographic toner according to the above <1> or <2>, T ₀ of the binder resin is preferably 70 to 120 ° C.

<4> In the electrophotographic toner described in <1> to <3>, the glass transition temperature Tg of the binder resin is 30.
The temperature is preferably ~ 80 ° C. <5> In the electrophotographic toner described in <1> to <4> above, the content of the wax in the toner is preferably 3 to 15% by weight.

<6> An electrophotographic developer comprising a toner and a carrier, wherein the toner contains at least a binder resin, a colorant and a wax, and fine particles are internally added. The absolute value G ^* of the complex elastic modulus at 10 rad / s and a strain of 10% is 1 × 10 ⁴ Pa
Where T ₀ (° C.) is the temperature T ₀ ,
T of the toner at a frequency of 10 rad / s and a distortion of 5%
an δ is 0.8 to 4.5, temperature T ₀ , frequency 10
rad / s, and the complex elastic moduli of the toner at strains of 5%, 10% and 100% are G ^* (5%) and G ^* (10%), respectively.
And G ^* (100%), ΔG ^* (10%) represented by the above equation (1) satisfies the above equation (2) and ΔG ^* (100%) represented by the above equation (3) Is the above equation (4)
And G ^* (5%) is 3 × 10 ^{4 to} 5 × 10 ⁵ Pa
G ^* (T ₀ + 40,5%) at a temperature T ₀ + 40 ° C., a frequency of 10 rad / s, and a strain of 5% is 1 × 10 ³ or more.
An electrophotographic developer having a pressure of 5 × 10 ⁵ Pa.

<7> In the electrophotographic developer of the above item <6>, the primary particle size of the fine particles is preferably 500 nm or less, and the volume fraction φ is preferably 0.03 to 0.5. <8> In the electrophotographic developer according to the above <6> or <7>, T ₀ of the binder resin is preferably 70 to 120 ° C.

<9> In the electrophotographic developer according to the above <6> to <8>, the glass transition temperature Tg of the binder resin is 30.
The temperature is preferably ~ 80 ° C. <10> In the electrophotographic developer according to any one of the above items <6> to <9>, the content of the wax in the toner is preferably 3 to 15% by weight.

<11> An image forming method for forming an image using an electrophotographic toner, wherein the electrophotographic toner contains at least a binder resin, a colorant and a wax, and fine particles are internally added. , Frequency 1 of the binder resin
When the temperature at which the absolute value G ^* of the complex elastic modulus at ₀ rad / s and the strain of 10% becomes 1 × 10 ⁴ Pa is T ₀ (° C.), the temperature T ₀ , the frequency is 10 rad / s, and the strain is 5%.
Tan δ of the toner is 0.8 to 4.5,
The complex elastic modulus of the toner at temperature T ₀ , frequency 10 rad / s, strain 5%, 10% and 100% is G
^{When **} (5%), G ^* (10%) and G ^* (100%), ΔG ^* (10%) represented by the above equation (1) satisfies the above equation (2) and the above equation (2). ΔG represented by 3)
^* (100%) satisfies the above formula (4), and the G ^* (5%)
Is 3 × 10 ^{4 to} 5 × 10 ⁵ Pa, and the temperature T ₀ +40
G ^* (T _{0) at} 10 ° C., a frequency of 10 rad / s, and a strain of 5%.
+ 40,5%) is 1 × 10 ^{3 to} 5 × 10 ⁵ Pa.

<12> The image forming method according to <11>,
The primary particle size of the fine particles is 500 nm or less,
The integration ratio φ is preferably 0.03 to 0.5. <13> The image forming method according to <11> or <12>,
The T of the binder resin ₀Should be 70-120 ° C
No.

<14> In the image forming method of <11> to <13>, the glass transition temperature Tg of the binder resin is 3
The temperature is preferably from 0 to 80 ° C. <15> In the image forming method according to any one of the above items <11> to <14>, the content of the wax in the toner is preferably 3 to 15% by weight.

[0032]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
The electrophotographic toner of the present invention contains a binder resin, a colorant and a wax, and has fine particles added internally. By containing the fine particles in a well-dispersed state, the physical properties of the toner in a molten state and a glass state change, and the viscoelastic properties of the toner can be freely controlled.

In order to control the fixing property of the toner and the smoothness of the fixed image, it is preferable to control the storage elastic modulus G ′ and the loss elastic modulus G ″ of the toner to appropriate values. In the case of the present invention, the fine particles uniformly dispersed in the toner at normal temperature can freely move when the toner is in a molten state, and it is considered that a network is formed by the interaction between the fine particles. The fine particle network can provide the toner with appropriate elasticity, and can reduce the change in the elastic modulus with respect to the temperature change.

Further, as a characteristic phenomenon of the fine particle-containing system, the viscoelastic behavior changes depending on the magnitude of the applied strain. This is considered to be caused by the collapse of the network of fine particles due to deformation due to strain. As the collapse of the network progresses, the complex elastic modulus G ^* decreases. In the fixing by the thermocompression bonding method, the toner is greatly deformed by the pressure of the fixing member. The change in the viscoelastic behavior at this time greatly affects the fixing performance. The present invention utilizes the change in the viscoelastic behavior of the toner.

That is, according to the present invention, the frequency is 10 rad / s,
At a strain of 10%, the absolute value G of the complex elastic modulus of the binder resin
^{When the} temperature at which ^* becomes 1 × 10 ⁴ Pa is T ₀ , the temperature T ₀ , the frequency 10 rad / s, the strain 5%, 10% and 1
The complex elastic modulus of the toner at 00% is G ^* (5
%), G ^* (10%) and G ^* (100%),
ΔG ^* (10%) represented by the following equation (1) satisfies the following equation (2) and ΔG ^* (1
00%) should satisfy the following expression (4).

ΔG ^* (10%) = | log (G ^* (10%) / G ^* (5%)) | / (log 10−log 5) (1). ΔG ^* (10%) ≦ 2.5φ + 0.1 (2). ΔG ^* (100%) = | log (G ^* (100%) / G ^* (5%)) | / (log 100−log 5) (3). ΔG ^* (100%) ≧ 0.8φ (4). In the formulas (2) and (4), φ indicates the volume fraction of the fine particles contained in the toner.

The G ^* (5%) is 3 × 10 ^{4 to} 5 × 1.
0 ⁵ Pa, temperature T ₀ + 40 ° C., frequency 10 rad /
s, G ^* (T ₀ + 40,5%) at 5% distortion is 1 × 1
It is good to be 0 ^{3 to} 5 × 10 ⁵ Pa.

ΔG ^* (10%) indicates the rate of change of the complex elastic modulus when a relatively small strain is applied, and is an index indicating the good releasability of the toner when fixing at a low temperature. In the oilless fixing by the thermocompression bonding method, when the toner is thermocompressed, a phenomenon may occur in which the toner layer is wound around the fixing member together with the transfer target body as an adhesive layer. In order to prevent winding, it is preferable that a change in the complex elastic modulus G ^* is small with respect to a minute distortion when the transfer target body is separated from the fixing device. The reason for this is that a toner having a high rate of change of G ^* has an extremely high yield value against distortion, and thus cannot be deformed as it is stuck to the surface of the fixing member when the toner separates from the fixing member. We believe that wrapping will occur.

ΔG ^* (10%) largely reflects the decrease in the storage modulus G ′ accompanying the collapse of the fine particle network. When the amount of the contained fine particles increases, the change in the fine particle network becomes more remarkable. Reflected in behavior. Therefore, ΔG ^* (10%) is the volume fraction φ of the contained fine particles.
When the value is within the range of the above formula (2), preferably the range of the following formula (2) ′, the effect of improving the elasticity by the fine particles sufficiently works to prevent winding and obtain good releasability. Can be. ΔG ^* (10%) ≦ 2.2φ + 0.1 Equation (2) ′.

Further, as a result of intensive studies, when the rate of change of the complex elastic modulus at T ₀ ° C is small, the rate of change is kept small even when the temperature is higher than T ₀ , and the effect of preventing offset is simultaneously obtained. It was found that it could be obtained. That is, when the relationship of the expression (2) is satisfied, the anti-offset property can be obtained because the network of fine particles is hardly broken even at a high temperature. ΔG ^* (10%) is 2.5
If it exceeds φ + 0.1, elasticity due to the fine particle network is lost due to strain, and the offset resistance tends to deteriorate.

ΔG ^* (100%) indicates a change in complex elastic modulus when a large strain is applied. If the complex elastic modulus hardly decreases even if the distortion increases, the high elasticity of the toner is maintained, and after the toner is heated and pressed, the elasticity tends to return to the original shape due to the elasticity. Poor smoothness and no gloss.

However, when G ^* decreases while the distortion reaches 100%, the elasticity decreases and tan δ increases at the same time, so that a smooth fixed image can be obtained. Further, when the volume fraction φ of the fine particles is large, the toner becomes more elastic. Therefore, when φ is large, the reduction rate of G ^* must be even greater in order to obtain image smoothness. Therefore, in order to obtain a sufficient smoothness of the fixed image, it is preferable to satisfy the above expression (4), preferably the following expression (4) ′. ΔG ^* (100%) ≧ 1.2φ Equation (4) ′.

The tan δ of the toner at a temperature T ₀ ° C, a frequency of 10 rad / s and a distortion of 5% is preferably 0.8 to 4.5. If tan δ is too small, the storage elastic modulus G 'will be too large, and the image smoothness tends to deteriorate. If tan δ is too large, the releasability tends to deteriorate due to insufficient elasticity.

Further, G ^* (5%) at the temperature T ₀ ° C is 3 ×
10 ^{4 to} 5 × 10 ⁵ Pa, preferably 4 × 10 ⁴ to 2 × 1
It is preferably 0 ⁵ Pa. When containing fine particles, the toner G ^* is raised compared with the binder resin G ^*. This is largely attributable to an increase in storage modulus G ′ due to the inclusion of fine particles. G
^{* If} (5%) is too small, good releasability tends not to be obtained due to insufficient elasticity. Conversely, G ^* (5
%), A low-temperature offset tends to occur, and the minimum fixing temperature tends to increase.

Further, in order to maintain good offset resistance and widen the fixable temperature range, G ^* (5%) at temperature T ₀ + 40 ° C. (that is, G ^* (T ₀ + 40,5%)) is 1 ×.
10 ^{3 to} 5 × 10 ⁵ Pa, preferably 2 × 10 ^{3 to} 3 × 1
It is preferably 0 ⁵ Pa. G ^* (T ₀ +40,5
%) Is too small, the elasticity is insufficient, and offset tends to occur. Conversely, G ^* (T ₀ +4
(0.5%) is too large, the elasticity tends to be high, and the smoothness of the fixed image tends to be poor.

The fine particles contained in the toner can be arbitrarily selected so as to satisfy the above range of viscoelasticity. However, the primary particle size of the fine particles is preferably 500 nm or less, preferably 100 nm or less.
The effect of improving the elasticity by the fine particles depends on the primary particle size of the particles. If the value of the primary particle size is too large, it tends to be difficult to obtain sufficient elasticity.

Further, the volume fraction φ of the fine particles also has a great influence on the viscoelasticity, and φ is preferably 0.03 to 0.5, more preferably 0.05 to 0.3. If φ is too small,
The amount of particles is insufficient to form a network of fine particles, and the effect of improving elasticity tends not to be obtained. If φ is too large, the network becomes too strong, so that the minimum fixing temperature rises and the smoothness of the fixed image tends to deteriorate.

The fine particles used in the present invention are not particularly limited. However, it is preferable to use colorless or white particles for use in a color toner. For example, as organic particles, vinyl, styrene, (meth) acrylic,
A single resin such as an ester, amide, melamine, ether, or epoxy resin or a copolymer resin thereof can be used. These may be those appropriately synthesized by a known production method, or commercially available ones. Examples of commercially available products include those described in “New Development of Fine Particle Polymers” (edited by Toray Research Center Co., Ltd.), and among others, Nippon Paint Co., Ltd.
Micro gel series, JSR Corporation's STADE
The X series, Soken Chemical's MR series and MP series are easily available.

As the inorganic particles used in the present invention, fine particles having a particle diameter in the above range, for example, silica, alumina, titanium oxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate, zinc oxide, silica sand, Examples include clay, mica, wollastonite, diatomaceous earth, cesium chloride, red iron oxide, chromium oxide, cerium oxide, antimony trioxide, magnesium oxide, zirconium oxide, silicon carbide, silicon nitride, and the like. These may be appropriately synthesized by a known method, for example, a gas phase method, a wet method, or the like, or a commercially available method may be used.

The inorganic particles may be surface-treated with a hydrophobizing agent or the like. As the hydrophobizing agent, a silane coupling agent, a titanate coupling agent, silicone oil, silicone varnish, or the like can be used. Examples of the silane coupling agent include hexamethyldisilazane, trimethylsilane, trimethylchlorosilane, dimethyldichlorosilane, methyltrichlorosilane, allyldimethylchlorosilane, benzyldimethylchlorosilane, methyltrimethoxysilane, methyltriethoxysilane, and isobutyltrisilane. Methoxysilane, trimethylmethoxysilane, hydroxypropyltrimethoxysilane, phenyltrimethoxysilane, n-butyltrimethoxysilane, n-hexylmethoxysilane, n-octyltrimethoxysilane, n-hexadecyltrimethoxysilane, n-octadecyl Trimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, vinyltriacetoxysilane, etc. Can be used.

As the silicone oil, for example, dimethylpolysiloxane, methylhydrogenpolysiloxane, methylphenylpolysiloxane and the like can be used. The fine particles may be used alone,
Two or more kinds may be used in appropriate combination.

Further, the fine particles of the present invention may be coated with a resin which may be the same as or different from a binder resin described later. In this case, the above T ₀ , that is, frequency 1
The temperature T _{0 at which} the absolute value G ^* of the complex elastic modulus of the binder resin at 0 rad / s and a strain of 10% becomes 1 × 10 ⁴ Pa is defined as follows.

When the fine particles of the present invention use the same binder resin as the binder resin to be used, the temperature T ₀ depends on the G ^{* of the} binder resin ^.
Is used. When the fine particles of the present invention are covered with a second resin different from the first binder resin, the temperature T ₀ is
It is obtained from G ^* of a resin comprising a mixture of the first binder resin and the second resin. Similarly, when a plurality of types of binder resins are used as the binder resin, the temperature T ₀ is obtained from G ^{* of the} resin composed of a mixture of the plurality of types of binder resins.

As the binder resin used in the present invention, a resin having a lower glass transition temperature than a binder resin conventionally used in a toner can be used. This is because by incorporating fine particles and wax inside the toner, even when a resin having a low glass transition point is used, the heat blocking property is not impaired. It is considered that the reason for this is that by containing fine particles, the storage elastic modulus in a glassy state is increased, and the movement of the binder resin due to diffusion of low molecular weight components is suppressed by the fine particles. Therefore, by combining the binder resin and the fine particles having a lower glass transition temperature than the conventional toner, low-temperature fixing can be performed without impairing the heat blocking property. For good heat blocking properties, the volume fraction φ of the fine particles is preferably in the above range.

The glass transition temperature of the binder resin is 30 to 80.
It is preferably in the range of ° C. The temperature T ₀ of the complex elastic modulus of the binder resin G ^* is 1 × 10 ⁴ Pa is from 70 to 12
It is preferably in the range of 0 ° C. Regarding both, if the temperature is too low, the heat blocking resistance tends to deteriorate,
If the temperature is too high, the minimum fixing temperature tends to increase. The glass transition temperature Tg is determined, for example, by a differential scanning calorimeter (manufactured by Mac Science: DSC3110, thermal analysis system 00).
1) (hereinafter abbreviated as "DSC"), and can be measured at a rate of temperature increase of 5 ° C./min. The temperature of the shoulder on the low temperature side of the endothermic point of the obtained chart can be defined as Tg.

As the binder resin, an ethylene resin such as polyethylene and polypropylene; a styrene resin such as polystyrene and α-polymethylstyrene; a (meth) acrylic resin such as polymethyl methacrylate and polyacrylonitrile; a polyamide resin; Resins; polyether resins; polyester resins and copolymer resins thereof. From the viewpoint of charge stability and development durability when used as a toner, styrene resins, (meth)
Acrylic resins, styrene- (meth) acrylic copolymer resins and polyester resins are preferred. Further, a polyester resin is more preferred from the viewpoints of low-temperature fixability and resistance to PVC adhesion of an image.

The following may be mentioned as monomers constituting the above-mentioned styrene resin, (meth) acrylic resin and copolymer resins thereof. That is, as the styrene monomer, styrene, α-methylstyrene, vinylnaphthalene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene, 2-ethylstyrene, 3-ethylstyrene, 4-ethylstyrene, etc. Examples thereof include alkyl-substituted styrene having an alkyl chain, halogen-substituted styrene such as 2-chlorostyrene, 3-chlorostyrene and 4-chlorostyrene, and fluorine-substituted styrene such as 4-fluorostyrene and 2,5-difluorostyrene. .

As (meth) acrylic acid monomers, (meth) acrylic acid, n-methyl (meth) acrylate, n-ethyl (meth) acrylate, n-propyl (meth) acrylate, (meth) acrylate N-butyl acrylate, (meth) acrylic acid
n-pentyl, n-hexyl (meth) acrylate, (meth)
N-heptyl acrylate, n-octyl (meth) acrylate, n-decyl (meth) acrylate, (meth) acrylic acid
n-dodecyl, n-lauryl (meth) acrylate, (meth)
N-tetradecyl acrylate, n-hexadecyl (meth) acrylate, n-octadecyl (meth) acrylate, isopropyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate, (meth) Isopentyl acrylate, amyl (meth) acrylate, neopentyl (meth) acrylate, isohexyl (meth) acrylate, isoheptyl (meth) acrylate, (meth)
Isooctyl acrylate, 2-ethylhexyl (meth) acrylate, phenyl (meth) acrylate, biphenyl (meth) acrylate, diphenylethyl (meth) acrylate, t-butylphenyl (meth) acrylate, (meth) acrylic acid Terphenyl, cyclohexyl (meth) acrylate, t-butylcyclohexyl (meth) acrylate,
Dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, methoxyethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, (meth) acrylonitrile, (meth) acrylamide, etc. . These monomers can be appropriately combined and produced by a known method.

As the polyester resin, an amorphous polyester resin is preferable. An amorphous polyester resin is advantageous in that the resin itself does not become cloudy due to light scattering by crystals, unlike a crystalline polyester resin. In the present invention, the amorphous polyester resin means a polyester resin which does not show an endothermic peak corresponding to the crystalline melting point in addition to an endothermic point corresponding to Tg in a DSC chart.

Other monomers used in the polyester resin include, for example, conventionally known divalent or trivalent monomer components such as those described in “Polymer Data Handbook: Basic Edition” (edited by The Society of Polymer Science, Baifukan). There are the above carboxylic acids and dihydric or trihydric or higher alcohols. Specific examples of these monomer components include the following.

Examples of the divalent carboxylic acid include succinic acid, glutaric acid, adipic acid, speric acid, azelaic acid, sebacic acid, phthalic acid, isophthalic acid, terephthalic acid, naphthalene-2,6-dicarboxylic acid and naphthalene-2. , 7-dicarboxylic acid, cyclohexanedicarboxylic acid, malonic acid,
Examples thereof include dibasic acids such as mesaconic acid, anhydrides thereof, lower alkyl esters thereof, and aliphatic unsaturated dicarboxylic acids such as maleic acid, fumaric acid, itaconic acid and citraconic acid. Examples of the trivalent or higher carboxylic acid include 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid and the like, and anhydrides and lower alkyls thereof. Esters and the like can be mentioned. These may be used alone or in combination of two or more.

Examples of the dihydric alcohol include bisphenol A, hydrogenated bisphenol A, ethylene oxide and / or propylene oxide adduct of bisphenol A, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, ethylene glycol, diethylene glycol, and the like. Examples thereof include propylene glycol, dipropylene glycol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, and neopentyl glycol. Examples of the trivalent or higher alcohol include glycerin, trimethylolethane, trimethylolpropane, and pentaerythritol. These may be used alone or in combination of two or more. If necessary, a monovalent acid such as acetic acid or benzoic acid, or a monohydric alcohol such as cyclohexanol or benzyl alcohol can be used for the purpose of preparing an acid value or a hydroxyl value.

The polyester resin may be used in any combination of the above-mentioned monomer components, for example, polycondensation (chemical doujinshi), polymer experiments (polycondensation and polyaddition: Kyoritsu Shuppan) or polyester resin handbook (edited by Nikkan Kogyo Shimbun) ) Can be synthesized using a conventionally known method,
The transesterification method or the direct polycondensation method can be used alone or in combination.

In the present invention, it is preferred that the binder resin be substantially free of tetrahydrofuran (hereinafter abbreviated as "THF") insoluble matter regardless of styrene, acrylic or polyester. When the THF-insoluble component is contained, the offset resistance is improved, but the glossiness of the image is impaired and the OHP light transmittance is impaired. THF
The insoluble content can be measured by dissolving the resin in THF so that the resin has a concentration of about 10% by weight, filtering the solution with a membrane filter or the like, drying the filter residue, and measuring the weight.

The molecular weight of the binder resin used in the present invention is, as for the styrene resin, the (meth) acrylic resin and the styrene- (meth) acrylic resin, a weight average molecular weight (hereinafter abbreviated as “Mw”) and a number average molecular weight. Molecular weight (hereinafter "Mn")
Mw is 30,000-100,0, respectively.
Preferably, Mn is 2,000 to 30,000, Mw is 35,000 to 80,000, and Mn is 2,500 to 20,000.
In the case of a polyester resin, Mw is 5,000 to 3
It is preferable that 000 and Mn are 2,000 to 8,000, and it is more preferable that Mw is 6,000 to 20,000 and Mn is 2,500 to 6,000. M
If w and Mn are too high, the minimum fixing temperature tends to increase, and if too low, image strength after fixing tends to be hardly obtained.

These molecular weights and molecular weight distributions can be measured by methods known per se. Generally, it is measured by gel permeation chromatography (hereinafter abbreviated as “GPC”). GPC measurement is, for example, GP
HLC-802 manufactured by TOYO SODA as C apparatus
A, oven temperature 40 ° C, column flow rate 1m per minute
1, the sample injection amount is 0.1 ml, the sample concentration is 0.5%, and manufactured by Wako Pure Chemical: GPC
Can be performed using THF. The calibration curve can be created, for example, using a standard polystyrene sample manufactured by TOYO SODA. The molecular weight and the molecular weight distribution in the present invention are measured as described above.

The toner of the present invention contains a colorant. The colorant is not particularly limited, and includes known colorants, and can be appropriately selected according to the purpose.

As a coloring agent, for example, carbon black,
Lamp black, aniline blue, ultramarine blue, calcoil blue, methylene blue chloride, copper phthalocyanine, quinoline yellow, chrome yellow, Dupont oil red, orient oil red,
Rose Bengal, Malachite Green Oxalate, Nigrosine Dye, CI Pigment Red 48: 1, CI Pigment Red 57: 1, CI Pigment Red 81: 1, CI Pigment Red 122, CI Pigment Yellow 97, CI Pigment Yellow 12, CI Pigment Yellow 17, CI
Pigment Blue 15: 1, CI Pigment Blue 15: 3, and the like.

The content of the colorant in the electrophotographic toner is preferably 1 to 30 parts by weight based on 100 parts by weight of the binder resin and the fine particles. It is preferable that the amount is as large as possible within a range that does not impair the smoothness of the image surface after fixing. When the content of the colorant is increased,
When obtaining images of the same density, the thickness of the image can be reduced, which is advantageous in that it is effective in preventing offset. Note that, depending on the type of the colorant, a yellow toner, a magenta toner, a cyan toner, a black toner, and the like can be obtained.

The toner of the present invention contains a wax. Examples of the wax include paraffin wax such as low molecular weight polypropylene and low molecular weight polyethylene, silicone resin, rosins, rice wax, carnauba wax and the like. In particular, the melting point is 40 ° C.-1
Those having a temperature of 50 ° C. are preferred, and more preferably 70 to 110.
° C is preferred.

However, if the content of the wax is too large, the wax on the surface or inside of the color-fixed image deteriorates the OHP projection, and when used as a two-component developer, the wax rubs against the carrier due to the friction between the toner and the carrier. The charging performance of the developer changes over time,
When used as a one-component developer, the wax may transfer to the blade due to the rubbing of the toner and the charging blade, causing the charging performance of the developer to change over time, including the deterioration of the fluidity of the toner. And degrade color image quality and reliability. Therefore, the content of the wax is preferably 3 to 15 parts by weight based on 100 parts by weight of the total of the binder resin and the fine particles.

Further, the toner of the present invention may contain inorganic fine particles, as appropriate, depending on the purpose of controlling transferability, fluidity, chargeability and the like.
Various additives known per se, such as organic fine particles, a charge control agent, and a release agent, may be added.

Generally, for the purpose of improving fluidity, the toner of the present invention preferably contains so-called externally added inorganic fine particles. As inorganic fine particles, for example, silica, alumina,
Titanium oxide, barium titanate, magnesium titanate, calcium titanate, strontium titanate, zinc oxide, silica sand, clay, mica, wollastonite, diatomaceous earth, sodium chloride, red iron oxide, chromium oxide, cerium oxide, antimony trioxide , Magnesium oxide, zirconium oxide, silicon carbide, silicon nitride and the like. Among these, titanium-based fine particles and silica fine particles are preferable, and fine particles subjected to a hydrophobic treatment are particularly preferable.
The primary particle size of the inorganic fine particles is preferably from 1 to 1000 nm, and the amount added is preferably 0.0
It is preferable to add 1 to 20 parts by weight externally.

As the organic fine particles, for example, polystyrene,
Examples thereof include polymethyl methacrylate and polyvinylidene fluoride. Those obtained by treating the surfaces of these fine particles with a silicone compound or a fluorine compound can also be preferably used. Organic fine particles are generally used for the purpose of improving cleaning properties and transfer properties.

Examples of the charge control agent include salicylic acid metal salts, metal-containing azo compounds, nigrosine and quaternary ammonium salts. The charge control agent is generally used for the purpose of improving chargeability.

The electrophotographic toner of the present invention can be produced according to a production method known per se. The production method is not particularly limited and can be appropriately determined depending on the purpose. For example, kneading and pulverizing method, kneading freezing and pulverizing method, submerged drying method, a method in which a molten toner is sheared and stirred in an insoluble liquid to form fine particles, a binder resin and a colorant are dispersed in a solvent, and fine particles are formed by jet spraying. Method, etc.,
Among them, the kneading and pulverizing method is preferable. In the kneading and pulverizing method, a binder resin, a colorant, and other additives are melt-kneaded using a Banbury-type kneader or a twin-screw kneader, and pulverized by a hammer mill, a jet-type pulverizer, or the like. The toner is classified by a force classifier or the like to obtain a toner, and is excellent in that the toner can be manufactured at a low cost with good material efficiency, and the additive can be internally added with relatively good dispersibility. When adding the fine particles to the inside of the toner, by using the fine particles that have been subjected to the flushing process in advance, the fine particles can be more uniformly dispersed inside the toner. The electrophotographic toner of the present invention can be suitably used as a toner in an electrophotographic developer.

The electrophotographic developer of the present invention may be a one-component electrophotographic developer or a two-component electrophotographic developer containing a carrier. In the case of a two-component electrophotographic developer, the carrier is not particularly limited,
A carrier known per se, for example, a resin-coated carrier or the like can be suitably used.

The resin-coated carrier is obtained by coating the surface of a core material with a resin. Examples of the core material include magnetic powders such as iron powder, ferrite powder, and nickel powder. Examples of the resin include a fluorine-based resin, a vinyl-based resin, and a silicone-based resin. The electrophotographic developer of the present invention may contain an additive or the like appropriately selected according to the purpose. For example, for the purpose of obtaining magnetism, iron, ferrite, irons including magnetite, metals exhibiting ferromagnetism such as nickel and cobalt, alloys or compounds containing these metals, magnetic materials, magnetizable materials are included. May be. The electrophotographic developer of the present invention can be suitably used for various image forming methods.

The image forming method of the present invention uses the electrophotographic developer of the present invention as the electrophotographic developer. The image forming method of the present invention includes an image forming step known per se, for example, a step of forming a latent image on a latent image carrier, a step of developing the latent image using a developer for electrophotography, a developed toner The method includes a step of transferring an image onto a transfer body, a step of fixing a toner image on the transfer body, and the like.

As the fixing device used in the image forming method of the present invention, a known contact-type heat fixing device can be used. For example, the fixing device has a rubber elastic layer on a cored bar and, if necessary, a fixing member surface layer. A heating roller fixing device comprising a heating roller and a pressure roller having a rubber elastic layer on a core metal and a fixing member surface layer as necessary, and a combination of the roller and the roller, A fixing device in place of a combination with a belt or a combination of a belt and a belt can be used.

The rubber elastic layer is preferably made of a heat-resistant rubber such as silicon rubber or fluorine rubber. Further, its thickness is preferably 0.1 mm to 3 mm, and its rubber hardness is preferably 60 or less. When the fixing member has an elastic layer, the fixing member is deformed following irregularities of the toner image on the transfer object, which is advantageous in that the smoothness of the image surface after fixing can be improved. If the thickness of the elastic layer is too large, the heat capacity of the fixing member becomes large, so that it takes a long time to heat the fixing member and the energy consumption thereof is undesirably increased. On the other hand, if the thickness of the elastic layer is too small, the deformation of the fixing member cannot follow the unevenness of the toner image, which is not preferable because unevenness occurs and the elastic layer cannot be effectively distorted for peeling.

For the surface layer of the fixing member, it is preferable to use silicon rubber, fluorine rubber, fluorine latex, or fluorine resin. In particular, fluororesins are excellent in terms of wear resistance.
As the fluororesin, a soft fluororesin containing polytetrafluoroethylene such as perfluoroalkoxyethyl ether copolymer (PFA), vinylidene fluoride or the like can be used. The base material (core) of the fixing member is preferably made of a material having excellent heat resistance, high strength against deformation, and good heat conductivity. In the case of a roll-type fixing device, for example, aluminum, iron, copper, or the like is selected as the base material of the fixing member. In the case of a belt-type fixing device, for example, a polyimide film, a stainless steel belt, or the like is selected.

The elastic layer and the surface layer of the fixing member may contain various additives depending on the purpose. For example, carbon black, metal oxide, ceramic particles such as SiC, etc. may be contained for the purpose of improving abrasion, controlling the resistance value and the like. Further, since the toner of the present invention is suitable for oil-less fixing and has a sufficient release property, it is not necessary to apply silicone oil or the like to the fixing member.

[0084]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

(Preparation of Binder Resin) 99.7 parts by weight (0.60 mol) of terephthalic acid and 66.5 parts by weight of isophthalic acid were placed in a reaction vessel equipped with a stirrer, a thermometer, a condenser, and a nitrogen gas inlet tube. 0.39 mol), 146.3 parts by weight (0.45 mol) of bisphenol A ethylene oxide 2 mol adduct, 19.83 parts by weight (0.15 mol) of 2,2-diethyl-1,3-propanediol, ethylene glycol 27 9.9 parts by weight (0.45 mol) and 2.2 parts by weight of dibutyltin oxide (0.00
9 mol). After the inside of the reaction vessel was replaced with dry nitrogen gas, the mixture was stirred and reacted at about 190 ° C. for about 6 hours in a nitrogen gas stream, and further heated to about 240 ° C. and stirred and reacted for about 3 hours. The pressure was reduced to 0.0 mmHg, and the mixture was stirred and reacted under reduced pressure for about 0.2 hours. Thus, a light yellow transparent amorphous polyester resin (binder resin A) having a molecular weight of Mw = 8,000, Mn = 3,500 and a glass transition temperature Tg of 52 ° C. was obtained.

(Preparation of Fine Particles) (Fine Particles B-1) In a reaction vessel equipped with a stirrer having a plurality of stirring blades, a reflux condenser, a thermometer, and a nitrogen inlet tube, 4,000 ml of 2-propanol as a solvent was used. A fine particle dispersion obtained by adding 300 parts by weight of synthetic silica powder Aerosil 130 (manufactured by Nippon Aerosil Co., Ltd., average primary particle size: 16 nm) to a slurry state, and 51.7 parts by weight of methyltrimethoxysilane (manufactured by Gerest) (0.38 mol) ) Was added to obtain a mixed solution. After replacing the inside of the reaction vessel with dry nitrogen gas, the temperature of the mixed solution was raised to about 80 ° C. while stirring under a nitrogen gas stream. Then, 0.1N hydrochloric acid was added as a catalyst in 50
Then, the mixture was stirred and reacted for about 6 hours. After the stirring reaction, the mixed solution was taken out, the treated microparticles were separated by centrifugation, and the mixture was mixed with ion-exchanged water, stirred and centrifuged to repeat washing five times. Finally, water was removed by freeze-drying to obtain fine silica particles B-1 treated with methyltrimethoxysilane.

Further, the fine particles B-1 were vacuum-dried at 100 ° C. for 1 hour, put into a 2% solution of aluminum hydroxide in dimethylene glycol dimethyl ether, and the amount of hydrogen generated by the reaction of the formula (5) was measured. Then, the amount of silanol groups was quantified, and the hydrophobicity was determined. As a result, the hydrophobicity of the surface of the fine particles B-1 was 55%.

NR—OH + LiAlH ₄ → LiAl (OR) _n H _4-n + nH ₂ (Formula 5)

(Fine Particle B-2) In the synthesis of the fine particle B-1, methyltrimethoxysilane was added to 82.9 parts by weight (0.38 mol) of 3,3,3-trifluoropropyltrimethoxysilane (manufactured by Gerest). Except having been changed, similarly to the above, fine particles B-2 subjected to hydrophobic treatment were obtained. The hydrophobization rate of the fine particles B-2 was 52%.

(Fine Particles B-3) In the synthesis of Fine Particles B-1, methyltrimethoxysilane was replaced with 3-aminopropyltrimethoxysilane (manufactured by Gerest) at 68.1 parts by weight (0.1% by weight).
38 mol) to obtain hydrophobically treated fine particles B-3. The hydrophobization rate of the fine particles B-3 is 5
4%.

(Fine Particle B-4) Hydrophobized silica RX300 (average primary particle size: 7 nm) manufactured by Nippon Aerosil Co., Ltd.
-4. The hydrophobization ratio of the fine particles B-4 was 88%.

(Resin Coating Treatment of Fine Particles) Fine particles B-1 to B-4 were coated with polyester resin A in order to improve the dispersibility of the fine particles in the toner. First, 1 kg of polyester resin A was dissolved in 20 L of tetrahydrofuran, and 2 kg of fine particles B-1 were added and dispersed in the resin solution. After stirring for 1 hour, tetrahydrofuran was evaporated at 45 ° C. under reduced pressure to obtain a dried product of the fine particles B-1 coated with the polyester resin A. Similarly, fine particles B-2 to B-4
Was also subjected to a resin coating treatment.

Example 1 The following components were mixed, melt-kneaded, pulverized, and classified to obtain a cyan toner having a volume average particle size of 6.4 μm. In addition, the fine particles B-1 used were those subjected to the resin coating treatment described above. The amount of polyester resin A is 84
It mixed so that it might become a weight part.

Polyester resin A 84 parts by weight Fine particles B-1 16 parts by weight Cyan pigment 4.5 parts by weight (Cyanine Blue 4933M, manufactured by Dainichi Seika Kogyo Co., Ltd.) Carnauba wax (Toa Kasei Corporation) 6 parts by weight

The particle size distribution of the toner was measured with a Coulter Counter TA-II (manufactured by Coulter). At this time, the volume fraction of the fine particles A was φ = 0.09. Hydrophobic silica fine particles (RX) are used for 100 parts by weight of the obtained toner.
50: manufactured by Nippon Aerosil Co., Ltd.) and externally mixed with a Henschel mixer to prepare toner X-1.

The viscoelastic behavior of this toner X-1 was measured by the following method. (Method of measuring viscoelasticity): Dynamic viscoelastic properties were measured as follows. As a measuring device, a rheometer manufactured by Rheometrics Co., Ltd., trade name “RDA2” (RHIOS system ver6.4.4) was used. First, in order to measure the temperature T _{0 at} which the complex elastic modulus G ^* of the binder resin becomes 1 × 10 ⁴ Pa, a parallel plate having a diameter of 8 mm was used, and was previously melted on a hot plate to obtain a diameter of 8 mm and a thickness of about 2 mm. The binder resin molded in the above was sandwiched between parallel plates, and the measurement was performed by sine wave vibration. The frequency is 10 rad / s, 30 ° C to 150 ° C
While increasing the temperature by 1 ° C. per minute in the range of
^{* Was} measured. After setting the initial value to 0.03%,
Changed by automatic measurement mode.

The viscoelasticity of the toner particles was measured at a temperature T ₀ using a cone and plate having a vertex angle of 0.1 rad and a diameter of 8 mm at a temperature T ₀ + 40 ° C.
d. A cone & plate having a diameter of 25 mm was used. In both cases, the samples were set so that the plate gap was 0.05 mm. For each of the temperatures T ₀ and T ₀ +40, the frequency was fixed at 10 rad / s, the measurement start strain was changed from 1 to 100%, and the strain rate dependency was measured.

Further, 8 parts by weight of the obtained toner X-1 and 100 parts by weight of a carrier were mixed to prepare a developer, and the fixing performance and the like were evaluated by the following procedure. (Image output): The carrier was a resin-coated carrier, in which a ferrite core was coated with a mixture of an amino group-containing vinyl polymer and a fluoroalkyl group-containing vinyl polymer. The prepared developer was applied to a Fuji Xerox color copier “A-color93” from which the fixing device was removed.
5 "and an unfixed image was output. The output image was a solid image having a size of 50 mm × 50 mm, and the image toner amount was adjusted to be 0.45 mg / cm ² . The paper used was "P paper" (trade name, manufactured by Fuji Xerox Office Supply Co., Ltd.). P paper is plain paper that has been used in many black and white copiers.

(Fixing method): A-color 9 is used for fixing.
The fixing device removed from the copier 35 was modified so that the roll temperature of the fixing device could be changed, and a fixing roller whose surface material was replaced with a Teflon (registered trademark) tube was used. The paper transport speed of the fixing unit is 160 mm per second,
The fixing was performed under oil-less conditions without applying silicone oil to the fixing device. An unfixed image of each toner was fixed by appropriately changing the temperature of the fixing device from 110 ° C. to 200 ° C. in steps of 5 ° C. to obtain a fixed image.

(Fixed image evaluation method): low-temperature offset,
The temperature at which fixing is started without winding is defined as the minimum fixing temperature, and the glossiness (gloss value) at each temperature is measured using a gloss meter “GM-26” manufactured by Murakami Color Research Laboratory Co., Ltd.
Using "D", the measurement was performed under the condition that the incident light angle on the sample was 75 degrees. Furthermore, the presence or absence of occurrence of a high-temperature offset was visually confirmed.

(Method of evaluating heat blocking): Toner 5
g was left in a chamber at 40 ° C. and 50% RH for 17 hours. After the temperature was returned to room temperature, 2 g of the toner was charged into a mesh having a mesh size of 45 microns, and was vibrated under certain conditions. The weight of the toner remaining on the mesh was measured, and the weight ratio to the charged amount was calculated. Those having a numerical value of 5% or less were judged to have good heat blocking properties. If this value is 5% or less, ○: 5-10%, △: 10%
The above was evaluated as x. Table 1 shows the results.

Comparative Example 1 In Example 1, fine particles B
In the same manner, toner X-2 having the following composition without containing -1 was prepared and evaluated.

100 parts by weight of polyester resin A 4.5 parts by weight of cyan pigment 4.5 parts by weight of cyanine blue (manufactured by Dainichi Seika Kogyo Co., Ltd.) 6 parts by weight of carnauba wax (manufactured by Toa Kasei Co., Ltd.)

(Example 2) In Example 1, fine particles B
A toner X-3 was prepared and evaluated in the same manner as in Example 1, except that the fine particle B-2 was used instead of -1.

Example 3 Toner X-4 was prepared and evaluated in the same manner as in Example 1, except that the following composition was used.

78 parts by weight of polyester resin A 16 parts by weight of fine particles B-3 6 parts by weight of fine particles B-4 4.5 parts by weight of cyan pigment 4.5 parts by weight (cyanine blue 4933M, manufactured by Dainichi Seika Kogyo KK) Carnauba wax (Toa Kasei) 6 parts by weight

Example 4 Toner X-5 was prepared and evaluated in the same manner as in Example 1 except that the following composition was used.

Polyester resin A 88 parts by weight Fine particles B-1 12 parts by weight Cyan pigment 4.5 parts by weight (Cyanine blue 4933M, manufactured by Dainichi Seika Kogyo KK) Carnauba wax (Toa Kasei Corporation) 6 parts by weight

Example 5 Toner X-6 was prepared and evaluated in the same manner as in Example 1, except that the following composition was used.

Polyester resin A 78 parts by weight Fine particles B-2 22 parts by weight Cyan pigment 4.5 parts by weight (Cyanine Blue 4933M, manufactured by Dainichi Seika Kogyo Co., Ltd.) Carnauba wax (Toa Kasei Corporation) 6 parts by weight

Comparative Example 2 In Example 1, the fine particles B
A toner X-7 was prepared and evaluated in the same manner as in Example 1, except that the fine particle B-3 was used instead of -1.

Comparative Example 3 In Example 1, fine particles B
A toner X-8 was prepared and evaluated in the same manner as in Example 1, except that the fine particle B-4 was used instead of -1.

Comparative Example 4 A toner X-9 was prepared and evaluated in the same manner as in Example 1 except that the following composition was used.

96 parts by weight of polyester resin A 4 parts by weight of fine particles B-1 4.5 parts by weight of cyan pigment 4.5 parts by weight of cyan pigment (manufactured by Dainichi Seika Kogyo Co., Ltd.) 6 parts by weight of carnauba wax (manufactured by Toa Kasei Co., Ltd.)

Example 5 Toner X-10 was prepared and evaluated in the same manner as in Example 3, except that the following composition was used.

78 parts by weight of polyester resin A 20 parts by weight of fine particles B-3 2 parts by weight of fine particles B-4 4.5 parts by weight of cyan pigment 4.5 parts by weight (cyanine blue 4933M, manufactured by Dainichi Seika Kogyo Co., Ltd.) Carnauba wax (Toa Kasei) 6 parts by weight

(Results of Evaluation of Toner) The T _{0 of the} polyester resin A was measured and found to be 95 ° C. Therefore 9
The viscoelasticity was measured and evaluated at 5 ° C. and 135 ° C. Table 1 shows the evaluation results of the viscoelasticity and the fixing property of each toner. In the table, column A shows the minimum fixing temperature (° C.), column B shows the temperature at which hot offset (or winding) occurs (° C.), column C shows the fixable temperature region (° C.) of gross 50 or more, and column D shows It represents heat blocking properties.

[0118]

[Table 1]

The toners used in the examples and comparative examples have a glass transition temperature Tg higher than that of the binder resin used in the conventional toner.
Polyester resin A having a low viscosity. When this toner is used, when silicone oil is applied to the fixing roll, the fixing can be performed at a lower temperature than the conventional color toner. This fusing evaluation was oilless fusing, and Fuji Xerox Office Supply plain paper "P paper", which has a lower paper density than coated paper dedicated to color printing, which is generally used in color copiers as fusing paper Is used. For this reason, when the conventional technique is used as it is without using the present invention, winding and offset are more likely to occur than when using coated paper.

The toner of Comparative Example 1 could not be peeled at a low temperature even if the glass transition temperature was lowered. This indicates that even if the wax is added, the releasability is still insufficient to release the plain paper. In Comparative Example 1, wrapping was performed only at 155 ° C. and fixing was possible without causing offset, but this was insufficient for practical use. Furthermore, since the glass transition temperature is lowered, the heat blocking resistance is poor.

Toners X-1, X-3 to X-6 (Example 1)
-5) contained fine particles therein and satisfied a specific viscoelastic range. All of these had a minimum fixing temperature of 120 to 125 ° C., a high-temperature offset occurrence temperature of 170 to 200 ° C., and very good low-temperature fixability and offset resistance. Further, when the gloss of the fixed image was measured for the minimum fixing temperature and the fixable temperature range immediately before the occurrence of the high-temperature offset, the gloss of the fixed image was 50 or more in a wide range, and an image excellent in glossiness and coloring was obtained. Was. In addition, because of containing the fine particles, the heat blocking property was also good.

[0122] Conversely, the toner X-7 (Comparative Example 2), T ₀
Since G ^* (5%) at + 40 ° C. is too small, 1
Winding occurred at 40 ° C., and a sufficient fixing temperature range was not obtained. The toner X-8 (Comparative Example 3)
^{* Since} the value of (10%) was too large, releasability was not obtained and winding occurred at 135 ° C. Toner X-9 (Comparative Example 4), the small amount of particulate, G at T ₀ ^* (5
%) And G ^* (5%) at T ₀ + 40 ° C. are both too low, so that the results are almost the same as those of the toner of Comparative Example 1, and the low-temperature fixing property and the offset resistance are not obtained, and the heat blocking property is also insufficient. Met. Toner X-10 (Comparative Example 5)
Was good in low-temperature fixability and offset resistance,
Since G ^* (100%) was too small, the image smoothness was poor, and at a temperature lower than 150 ° C., the gloss did not reach 50, and sufficient gloss was not obtained. Therefore, the toner X-10
(Comparative Example 5) did not satisfy the object of the present invention to obtain a high-gloss fixed image even at low-temperature fixing.

[0123]

According to the present invention, it is possible to provide an electrophotographic toner which is excellent in low-temperature fixing property and offset resistance, has good releasing property even in oilless fixing, and has a wide fixing temperature range. Further, according to the present invention, it is possible to provide an electrophotographic toner which is excellent in the smoothness of a fixed image and forms a stable and high gloss image.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Satoshi Yoshida 1600 Takematsu, Minamiashigara-shi, Kanagawa Prefecture Inside Fuji Xerox Co., Ltd. (72) Inventor Daisuke Okuda 1600 Takematsu, Minamiashigara-shi, Kanagawa Prefecture Fuji Xerox Co., Ltd. Inventor Yoshio Shoko 1600 Takematsu, Minamiashigara-shi, Kanagawa F-term in Fuji Xerox Co., Ltd. (Reference) 2H005 AA01 AA06 AA21 CA03 CA04 CA08 CA14 CA26 CB07 CB10 CB13 DA06 DA10 EA03 EA07 EA10

Claims (3)

[Claims] 1. An electrophotographic toner comprising at least a binder resin, a colorant and a wax and internally added fine particles, wherein the binder resin has a frequency of 10 rad / s.
The absolute value G ^* of the complex elastic modulus at a strain of 10% is 1 × 10 ⁴
Assuming that the temperature at which Pa is T ₀ (° C.), the tan δ of the toner at a temperature T ₀ , a frequency of 10 rad / s and a strain of 5% is 0.8 to 4.5, and a temperature T ₀ and a frequency of 10 rad / s. s, the complex elastic moduli of the toner at 5%, 10% and 100% of strain are G ^* (5%) and G ^* (1
0%) and G ^* (100%), the following equation (1)
ΔG ^* (10%) represented by the following expression (2) and ΔG ^* (100%) represented by the following expression (3) satisfy the following expression (4), and the G ^* (5%) Is 3 × 10 ^{4 to} 5 × 10
⁵ Pa, temperature T ₀ + 40 ° C., frequency 10 rad /
s, G ^* (T ₀ + 40,5%) at 5% distortion is 1 × 1
0 ³ to 5 × 10 Toner for electrophotography, characterized in that ⁵ a ^{Pa; ΔG * (10%)} = | log (G * (10%) / G * (5%)) | / (log 10- log 5) Equation (1) ΔG ^* (10%) ≦ 2.5φ + 0.1 Equation (2) ΔG ^* (100%) = | log (G ^* (100%) / G ^* (5%)) | / ( log 100-log 5) Equation (3) ΔG ^* (100%) ≧ 0.8φ Equation (4) (In Equations (2) and (4), φ represents the volume fraction of fine particles contained in the toner.) Shown). 2. An electrophotographic apparatus comprising a toner and a carrier.
A developer, wherein the toner is at least a binder resin,
Containing fines and wax and no fine particles added internally
The frequency of the binder resin is 10 rad / s and the strain is 10%.
Value G of the complex modulus of elasticity^*Is 1 × 10^FourTemperature that becomes Pa
Degree T₀(° C), the temperature T₀, Frequency 1
Tanδ of the toner at 0 rad / s and 5% distortion is
0.8 to 4.5 and the temperature T₀, Frequency 10 rad /
s, 5%, 10% and 100% distortion of the toner
Complex modulus is G^*(5%), G^*(10%) and G ^*
(100%), ΔG represented by the following equation (1)
^*(10%) satisfies the following formula (2) and the following formula (3)
ΔG represented by^*(100%) satisfies the following equation (4)
And the G^*(5%) is 3 × 10^Four~ 5 × 10^FivePa
Temperature T₀+ 40 ° C, frequency 10 rad / s, distortion 5
G in%^*(T₀+ 40,5%) is 1 × 10^Three~ 5x
10^FiveΔG, a developer for electrophotography characterized by Pa; ΔG^*(10%) = | log (G^*(10%) / G^*(5%)) | / (log 10-log 5) Equation (1) ΔG^*(10%) ≦ 2.5φ + 0.1 Equation (2) ΔG^*(100%) = | log (G^*(100%) / G^*(5%)) | / (log 100-log 5) Equation (3) ΔG^*(100%) ≧ 0.8φ Expression (4) (In Expressions (2) and (4), φ is contained in the toner.
1 shows the volume fraction of fine particles. ). 3. An image forming method for forming an image using an electrophotographic toner, wherein the electrophotographic toner contains at least a binder resin, a colorant and a wax, and fine particles are internally added, The frequency of the binder resin is 10 rad.
/ S, the absolute value G ^* of the complex modulus at 10% strain is 1
When the temperature at which the pressure becomes × 10 ⁴ Pa is T ₀ (° C.), the tan δ of the toner at a temperature T ₀ , a frequency of 10 rad / s, and a strain of 5% is 0.8 to 4.5.
₀ , frequency 10 rad / s, distortion 5%, 10% and 10
The complex elastic modulus of the toner at 0% was G ^* (5
%), G ^* (10%) and G ^* (100%),
ΔG ^* (10%) represented by the following equation (1) satisfies the following equation (2) and ΔG ^* (1
00%) satisfies the following equation (4), and G ^* (5%) is 3
× 10 ⁴ -5 × 10 ⁵ Pa, G ^* (T ₀ +4) at a temperature T ₀ + 40 ° C., a frequency of 10 rad / s, and a strain of 5%.
(0.5%) is 1 × 10 ^{3 to} 5 × 10 ⁵ Pa; ΔG ^* (10%) = | log (G ^* (10%) / G ^* (5%) ) | / (Log 10−log 5) Equation (1) ΔG ^* (10%) ≦ 2.5φ + 0.1 Equation (2) ΔG ^* (100%) = | log (G ^* (100%) / G ^* ( 5%)) | / (log 100-log 5) Equation (3) ΔG ^* (100%) ≧ 0.8 φ Equation (4) (In Equations (2) and (4), φ is contained in the toner.) Shows the volume fraction of the fine particles.)