JP3222976B2 - Electrophotographic developer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic developer used for forming an image by visualizing an electrostatic latent image.

[0002]

2. Description of the Related Art An electrophotographic image forming method is a very general image forming method, and an image is formed by the following process. First, an electrostatic latent image is formed on a photoreceptor obtained by laminating a photoconductive insulator on a conductive support, and then the toner, which is a charged particle, is electrostatically applied to the electrostatic latent image. The toner image is developed by being adhered thereto, and further the toner image is transferred to a transfer material such as paper, and then fixed by heat and pressure to obtain an image on the transfer material. After the transfer, the toner remaining on the photoreceptor is removed by a cleaning means such as an elastic blade or a brush.

[0003] The method of charging the toner, which is a charged particle, includes a method called a two-component development method in which the toner is rubbed with a carrier coated with iron powder, ferrite, or the like, or a magnetic or non-magnetic method without using a carrier. There is a method called a one-component developing method in which the toner is brought into contact with a frictional charging member in a developing device.

The process that consumes the most energy in the electrophotographic process is fixing of a toner pattern on a transfer material by heat. However, if the melting property of the toner is simply increased in order to reduce the fixing energy, offset development in which the toner is transferred onto the fixing roller occurs, storage stability is reduced, and crushing / aggregation (blocking) due to a reduction in mechanical strength is performed. -Problems such as sticking will occur. For this reason, microcapsule toners and the like that can be fixed at a low temperature are used. However, microcapsule toners are generally spherical, and in the case of particles having a relatively small particle size of 8 μm or less, after transfer, an elastic plate or the like is used. When the residual toner on the photoreceptor is removed by the cleaning member, the cleaning member easily slips between the cleaning member and the photoreceptor. At the same time, although the ease of fixing is improved, the thermal stability, mechanical strength and the like are relatively low, and none of them can withstand long-term use in a developing device having a lot of mechanical stress.

Further, in recent years, full-color electrophotography has been developed, and many full-color toners and developers have been commercialized. Generally, full color developers include:
The toner itself uses a non-magnetic two-component developer. This is because the magnetic toner limits coloring. The following characteristics are required for the color toner. First
In addition, the toner is sufficiently melted at the time of fixing so that the fixed toner does not cause irregular reflection to light and impair the color reproducibility, and the surface of the fixed image becomes smooth. Secondly, since it is necessary to fix an aggregate of toner particles in which toner layers of a plurality of colors are stacked, the toner has an optical transparency so that the toner in the upper layer does not interfere with the color of the toner in the lower layer. For this reason, the full-color toner, which was sufficient if the monochrome toner was fixed to the transfer material, needs to be more fully melted, and therefore needs to have a thermal characteristic of melting at a relatively low temperature. is there. However, the toner is required to be exposed to mechanical stress in a toner hopper, a developing device, a photoreceptor, a cleaner, or the like, equivalent to a monochrome toner, and to have sufficiently high mechanical strength.

On the other hand, in the case of the above-described developing method using a one-component developer, particularly when a non-magnetic one-component developer is used, it is not necessary to control the toner concentration, and the developing device can be reduced in size, simplified, and lightened. There are many merits such as the possibility of conversion. However, in this developing method, the electric charge is applied to the toner by pressing a frictional charging member such as a blade, a roller, or a brush against the toner layer on the developing roller, and performing frictional charging between the toner and the frictional charging member. In order to stably supply a sufficient charge to the toner, it is necessary to optimize the material and pressure of the frictional charging member. However, a large mechanical stress is applied to the toner, and the toner is easily fixed or filmed on the frictional charging member, the developing roller, and the like, and the fixing and filming maintain the stability and uniformity of the charging. It becomes difficult.

For this reason, the toner is required to have higher strength against mechanical stress than the toner for a two-component developer. On the other hand, from the viewpoint of the fixing property process, it is also required that the material be easily melted thermally. This non-magnetic one-component developing system can be applied to simple full-color image formation, but in this case, it is necessary to also have the above-mentioned characteristics as a color toner.

[0008]

SUMMARY OF THE INVENTION The object of the present invention is as follows.
To provide a developer capable of fixing to a transfer material with low energy; second, to provide a developer having a good cleaning property; and third, to obtain a good full-color image. To provide a developer that can
And a long-life non-magnetic one-component developer.

[0009]

[0010]

According to the present invention (claim 1), two different softening points are used.
More than one kind of resin, contains irregularly shaped core particles containing a resin having a low softening point, and partially formed around the core particles, contains a resin having a higher softening point than the resin having a lower softening point. to a toner containing a plurality of particles, the straight line enveloping the outer peripheral side of the outline of the plurality of particles, to provide an electrophotographic developer, characterized in that does not intersect the outer periphery of the core particle.

According to the present invention (claim 2), two different softening points are used.
A plurality of particles containing at least one kind of resin and having a resin having a lower softening point than the resin having a higher softening point, the outer periphery of which is coated with at least one minute of the resin having a higher softening point, and a plurality of particles are aggregated and integrated. An electrophotographic developer is provided.

[0013]

The electrophotographic toner according to the first aspect of the present invention comprises:
Two or more kinds of particles each containing two or more kinds of resins having different softening points as main components are aggregated and integrated. According to this toner, the high softening point area and the low softening point area are present in the toner, so that the mechanical strength is maintained in the high softening point area, and the low-temperature fixability in the low softening point area, particularly The color toner can maintain transparency at the time of fixing. In general, a high softening point resin and a low softening point resin are uniformly mixed as a toner binder as a toner binder, and there are many cases in which a device having two peaks in molecular weight is devised. This is essentially different from the above. According to the toner of the present invention, both the fixing property and the mechanical properties are improved, and the effect of the mechanical strength is particularly remarkable. This effect increases as the volume per region of the high softening point resin increases, and the diameter of the high softening point resin region is approximately 0.1 μm or more, preferably 0.5 μm.
The effect is high in the above cases. However, if the diameter of the high softening point resin region is at least 0.5 times the particle size of the toner, on the other hand, the meltability becomes insufficient, and there is a problem in the fixability and transparency.

Further, as similar to this, as disclosed in Japanese Patent Application Laid-Open No. 2-1869, a toner in which high softening point polymer fine particles are dispersed in a low softening point resin is also disclosed. This is obtained by a method of dispersing and mixing low softening point particles and high softening point particles during melt kneading,
Basically, it is necessary that the particles having a high softening point do not soften or melt at the time of melt-kneading, that is, it is necessary that there is a sufficient difference between the two softening points.

On the other hand, in the method disclosed in the present invention for forming toner particles by aggregating the high softening point particles and the low softening point particles, any method is possible regardless of the difference in softening point between the two kinds of particles. Can be set for the molecular weight and softening point, and the dispersibility of the particles is further improved. Further, according to the present invention, an irregular toner is formed unlike the conventional capsule toner, and a good cleaning property can be exhibited even with a toner having a particle diameter of 5 to 8 μm.

The toner for electrophotography according to the second aspect of the present invention comprises at least two kinds of resins having different softening points as a component, and is formed by aggregating a plurality of particles containing a resin having a low softening point. A resin having a high softening point is continuously coated around fixed core particles. According to this toner, even when the toner particle size is as small as 8 μm or less, the cleaning property by blade cleaning or the like does not decrease, and at the same time, the mechanical strength is maintained by the coating layer having a high softening point, and the resin area having a low softening point is maintained. Therefore, it is possible to maintain the low-temperature fixing property, particularly the transparency at the time of fixing in a color toner.

The toner according to the second aspect of the present invention can form a toner mainly focusing on mechanical strength and cleaning properties. In order to maintain the mechanical strength of the toner, it is particularly effective that the thickness of the coating resin is 0.7 μm or more. Conventionally, there has been a concept of a microcapsule in which a material having a low softening point is coated around a material having a low softening point. Although disclosed in Japanese Patent Application Laid-Open No. 58-3444, the toner according to the second aspect of the present invention includes:
Since the core particles are not particles obtained by the pulverization method, but are irregular particles obtained by aggregating a plurality of particles, a low-cost toner having good cleaning properties can be obtained.

The toner for electrophotography according to the third aspect of the present invention contains at least two kinds of resins having different softening points as components, and contains a resin having a high softening point around particles containing the resin having a low softening point. In a toner having a plurality of regions,
It is characterized in that a straight line enveloping the outline on the outer peripheral side of the region containing the high softening point resin does not intersect with the outer periphery of the region containing the low softening point resin. According to this toner, when the toner comes into contact with another member such as a carrier, a developing roller, an inner wall of a developing device, a toner hopper, a photoreceptor, a doctor blade, a stirring blade, etc., the inside resin region having a low softening point is directly contacted with another member. Therefore, the problem of sticking and crushing hardly occurs, and at the same time, the ratio of the resin having a high softening point to the entire toner can be minimized. In the present toner, the cleaning property and the high fixing property at a low temperature, particularly the color toner, are focused on the transparency at the time of fixing.

The toner for electrophotography according to the fourth aspect of the present invention comprises at least two kinds of resins having different softening points as components, and has a low softening property in which part or all of the outer periphery is covered with a resin having a high softening point. Aggregate primary particles containing point resin,
It is one. According to this toner, a single microcapsule toner in which the surroundings of particles containing a resin having a low softening point is generally covered with a shell having a high softening point maintains its strength only in the outer shell, so that the mechanical strength is substantially increased. Is insufficient, whereas a plurality of microscopic microcapsule toners are aggregated and integrated, so that a high softening point resin region having a three-dimensional network structure is formed inside one toner. The structure is such that the amount of components is minimized and the mechanical strength is sufficiently maintained. The toner of the present invention has mechanical strength, fixing strength, toner transparency, and cleaning properties. The primary particles constituting the toner according to the fourth aspect of the present invention preferably have a particle diameter of 0.2.
９9 μm, more preferably 0.5-5 μm, and the thickness of the shell wall of the primary particles is desirably 2-40% of the primary particle diameter.

[0020]

The present invention will be described below in more detail with reference to Examples of the present invention.

FIG. 1 is a view schematically showing an image forming apparatus using the electrophotographic toner of the present invention. As shown in FIG. 1, a charging device 2 is provided near the photoconductor 1,
The photosensitive member 1 uniformly charged by the charging device 2
By irradiating the light L from the exposure device 3, an electrostatic latent image is formed. Here, as the photoconductor 1, a drum-shaped one in which a photosensitive layer is applied to a cylinder of aluminum alloy or the like is often used, but a belt-shaped one such as a metal belt or a resin or paper whose surface is conductively used is also used. Is done. In the case of a belt shape, a seamless shape is particularly desirable.

The charging device 2 generally uses a non-contact corona discharge such as a corotron or a scorotron. In order to reduce the amount of generated ozone, a contact-type charging device using a roller, a brush, a blade, or the like is used. Devices can also be used. In general, when a contact-type charging device is used, the effect of residual cleaning on the image quality of residual toner is greater. That is, when the residual toner is caught between the contact-type charging device and the photosensitive member, uneven charging is caused.

The exposure device 3 includes a laser scanning head such as a semiconductor laser, a solid scanning head such as an LED element, a fluorescent tube, and an EL element, and a reflected light obtained by irradiating a document with light such as a halogen lamp or a fluorescent lamp. Can be used.

The electrostatic latent image is developed by supplying toner from a developing unit 4 having a built-in toner of the present invention, which is provided close to or in contact with the photoconductor 1, and a toner image is obtained. Next, the toner image on the photoreceptor is transferred onto a transfer material 6 such as a paper or a film by a transfer device 5 provided close to or in contact with the photoreceptor 1, and the transfer material 6 on which the toner image has been transferred. Is fixed by the fixing device 7. On the other hand, the untransferred toner remaining on the photoreceptor 1 is collected and removed from the photoreceptor by the cleaning device 8, and further, the charge of the photoreceptor 1 is removed by the charge removing device 9, and the process proceeds to the next cycle. Become.

Here, the developing method includes a method using a two-component developer composed of a magnetic carrier and a non-magnetic toner, a method using a developer composed of a magnetic carrier and a magnetic and non-magnetic toner, and a method using a magnetic material composed of only a magnetic toner. There are various systems such as a system using a component developer and a system using a one-component non-magnetic developer consisting of only a non-magnetic toner. Among them, the cause of the mechanical stress on the toner is that in the case of the developer using magnetic particles, the toner may collide with each other or with the carrier.
Some are caused by friction, the other is caused by friction with a doctor blade or the like for regulating the layer thickness of the developer, and the other is caused by collision or friction with a stirring means in a developing device. In addition,
The non-magnetic one-component developing method will be described in more detail below with reference to other drawings.

The fixing device 7 is composed of two elastic rollers, or one of them is a metal roller, and the heat source may be provided on both rollers or may be provided only on one side. Since the offset phenomenon occurs when the toner is melted at a high temperature, a solid or liquid release agent is applied to the roller surface.
Particularly, in the case of a color toner requiring transparency at the time of fixing, a releasing agent such as silicone oil is constantly supplied.

Further, the cleaning device 8 includes the support member 1.
Cleaning blade 10 which is an elastic body fixed to 1
Is in contact with the photoconductor 1, and the residual toner on the photoconductor 1 rotating in the direction of arrow A is
Is scraped into the cleaning device 8. This method is the most common and compact cleaning method called the blade cleaning method.However, when cleaning is not performed sufficiently, the method of scraping with a brush such as a fur brush, a magnetic brush, or the like, alone or in combination with the blade method Sometimes used by

The residual toner on the photoreceptor 1 is strongly adhered to the cleaning blade 10 electrostatically and tends to remain between the photoreceptor 1 and the cleaning blade 10. This causes a cleaning failure. As shown in FIG. 1, in the method in which the toner is scraped off by the cleaning device 8, the toner is dropped by gravity and hardly remains at the tip of the cleaning blade. However, in a structure in which the cleaning blade employs a method in which the residual toner on the photoreceptor 1 is scraped, the toner is likely to remain at the tip of the cleaning blade, and cleaning failure is more likely to occur.

In addition, since cleaning contact between the cleaning blade 10 and the photoreceptor 1 needs to be ensured uniformly, the cleaning failure is more likely to occur as the radius of curvature of the photoreceptor 1 decreases. Specifically, when the radius of curvature is 30 mm or less, cleaning failure becomes remarkable. It should be noted that the cleaning failure is remarkable when the particle diameter of the toner is short, specifically, 8 μm or less, particularly 6 μm or less. Further, as the shape of the toner is closer to a true sphere, cleaning failure is more likely to occur due to slippage between the cleaning blade 10 and the photoconductor 1.

FIG. 2 is a sectional view of a typical developing device used in the contact one-component developing method. The contact one-component developing method does not require carrier, magnetic roller, toner concentration control, etc.
This is a development method that can be reduced in size and cost. Hereinafter, FIG.
The development process will be briefly described with reference to FIG.

In this developing device, a thin layer of non-magnetic one-component contact developing toner is formed on the surface of the developing roller 109 having conductivity and elasticity, and development is performed by bringing the thin layer into contact with the surface of the photosensitive drum 102. You. Toner container 11
2 is sent to the toner supply roller 111 while being stirred by the mixer 114. After the toner is supplied to the developing roller 109 by the toner supply roller 111, the toner particles are charged by friction with the surface of the developing roller 109, and are electrostatically attracted and conveyed.
Thereafter, the amount of toner transported is regulated by the blade 110, and at the same time, both are charged by friction.

Here, reversal development is performed using a negatively charged organic photosensitive drum, the toner is a negatively charged toner, and the blade 110 is also made of a material that can easily give a negative charge. -600V. A developing bias of -300 to -450 V is supplied to the shaft 109a of the developing roller 109 via a load resistor, and the developing roller 109 is rotated about 1.2 to 4 times faster than the photosensitive drum 102 in the direction of the arrow. 102 and 1-4 mm
Contact rotation with a contact width of Since the toner particles are frictionally charged even at the developing position, an extremely sharp image with little fog is obtained.

The undeveloped toner is supplied to the recovery blade 1
15 and returns to the inside of the developing device. A member 116 is attached so that the dropped toner does not stain the inside of the apparatus or the transfer paper. Further, the developing device shown in FIG. 2 has an advantage that the toner does not fall even if the entire device is placed upside down. Reference numeral 121 denotes a baffle plate attached to the blade holder, which is in contact with a foam material 123 made of maltprene or the like attached to the surface of the blade 110 to suppress leakage of toner and vibration of the blade. As a result, a good toner layer can be formed on the developing roller 109. In the description of FIG. 2, reversal development is performed using a negatively charged photoconductor, but a positively charged photoconductor may be used or regular development may be performed.

Next, a color image forming apparatus will be described. FIG. 3 shows a color image forming apparatus according to one embodiment of the present invention. In this apparatus, the photosensitive member 201 and the charging device 20
2. Four sets of a laser exposure device 203, a developing device 200, a transfer device 209, a blade cleaning device 204, and a neutralization lamp 205 are arranged for four colors of black, yellow, magenta, and cyan.

A transfer material 213 such as paper or an OHP sheet is conveyed on the transfer belt 208 from the direction of the arrow, and a transfer voltage is applied by a transfer device 209 from below the transfer belt 208 at a portion where the transfer material 213 contacts the photosensitive member 202. The toner that has been applied and developed on the photoconductor 202 in the process described with reference to FIG. 1 is transferred to the transfer material 213. This is sequentially performed for each color, and the toner image is superimposed on the transfer material 213.

As the transfer device 209, a device that applies a bias voltage to an elastic roller is used. The toner image superimposed on the transfer material 213 is
Heat is applied to the toner by passing between the heating roller 211 and the pressure roller 212 in the toner image 10, and the toner is fixed on the image support. Thus, a full-color image is obtained.

FIG. 4 is a sectional view of a contact type non-magnetic one-component developing device 200 used in the color image forming apparatus shown in FIG. This developing apparatus has the same basic structure as the contact type non-magnetic one-component developing apparatus shown in FIG. 2, but has a more compact structure. In this developing device, the blade 1
A phosphor bronze plate having a thickness of 0.2 mm is used for 10, and urethane rubber of JIS-A standard 80 ° is used for a contact portion 109 a with the developing roller 109.

FIG. 5 is a conceptual sectional view of the fixing device 210 used in the color image forming apparatus shown in FIG. The heating roller 211 has a structure in which a silicon rubber layer is formed on a hollow cored bar.
Reference numeral 12 denotes a pressure roller. Pressure roller 212
Is formed with a silicon rubber layer having a surface coated with a fluororesin on a metal core, and is configured to rotate by pressing against a heat roller. When the heating roller 211 is heated, the release agent applying member 215 is also heated, and the silicone oil is leached and supplied to the heating roller 211. The excessively supplied silicon oil is scraped off by the cleaning blade 216 when the heating roller 211 rotates, and is applied to the surface of the heating roller 211 in a thin film form. As the release agent, dimethyl silicone oil having a viscosity of around 300 cs is desirable. When the image support 213 passes between the fixing rollers, a part of the silicone oil adheres to the image support, and the silicon oil is consumed.

Hereinafter, various aspects of the electrophotographic toner of the present invention will be described with reference to the drawings.

FIG. 6 shows an electrophotographic toner according to a first embodiment of the present invention, wherein particles each containing two or more resins having different softening points as main components are coagulated and integrated, and the production thereof. It is a conceptual diagram of a law. In the figure, black portions are particles and regions containing a resin having a high softening point, and white portions are particles and regions containing a resin having a low softening point. In the following figures, this division is common.

FIG. 6 (a) shows a case where the primary particles before aggregation are spherical particles formed by suspension polymerization, emulsion polymerization, dispersion polymerization, etc., and FIG. The case of irregular particles formed by pulverization is shown. In addition to resins, colorants such as pigments, charge control substances, and additives such as waxes are generally contained in each particle, and the type of these additives may be changed for each type of particle.

For example, particles A containing a resin having a high softening point
And when the particles B containing a resin having a low softening point are aggregated,
Particle A contains a wax and a charge control substance, Particle B contains a colorant, or Particle A contains a charge control substance, Particle B contains a colorant and no wax. Are possible. Thereby, at the time of fixing and melting, the particles having a lower softening point containing the colorant have a lower viscosity at the time of melting, so that a toner image with higher transparency can be obtained. Further, it is possible to uniformly disperse additives that are difficult to disperse mutually in toner particles, and it is also possible to aggregate particles of three or more types of additives different from each other.

The first and most effective method of aggregating particles is as follows: from a state in which the particles are uniformly dispersed in a liquid, to a chemical environment condition such as PH, a mechanical condition such as a stirring speed, and a thermal condition. By changing the conditions for controlling the dispersibility, a controlled aggregation state is formed, and this is further fused and integrated. The temperature at the time of the formation of the first aggregated state is desirably at least equal to or lower than the high softening point temperature, and may be equal to or higher than the softening point of the low softening point particles. Secondly, there is a system in which the ordered mixture is formed by a mixer in a powder state and then integrated by a mechanical system such as collision in a high-speed air stream. Third, the powder group is passed through a hot air stream,
There is a welding method.

Here, points to be noted when aggregating these particles will be described. If two or more kinds of particles having different softening points are simply agglomerated arbitrarily, a component distribution always occurs. As a result, even if the amount is small, agglomerated particles having only a low softening point or agglomerated only having a high softening point are obtained. Particles will be formed with a certain probability. Among them, particularly, aggregates of particles having a low softening point cause undesirable phenomena such as sticking in a developing device and blocking which is aggregation of toners. Regarding this point, the second and third mechanical coagulation systems are difficult to control, whereas the system using coagulation in the first liquid is the easiest to control.

Specifically, in the second method, the collision between the elastic bodies causes repulsion and re-separation, whereas the particles having a low softening point are likely to be united once they collide with each other. Are more likely to be formed in which the content of is larger than the statistical distribution. In order to avoid this, for example, a method of forming secondary particles after coating the periphery of the low softening point particles with high softening point particles containing an inorganic substance such as silica, titanium oxide, and zinc oxide is adopted. Can be done.

In order to prevent the formation of aggregated particles having only a low softening point and aggregated particles having only a high softening point in the first method,
As shown in FIG. 6C, for example, the low softening point particles and the high softening point particles are dispersed in a liquid while being charged to different polarities with a surfactant or the like, and the low softening point particles and the high softening point particles are dispersed. Are agglomerated at a constant ratio, and then a plurality of units are aggregated to obtain particles having a desired particle size. In this case, the agglomeration ratio of the two particles tends to be 1: 1. However, in order to form an agglomerate with a large ratio of one of the particles, as shown in FIG. Means for charging again and charging either one of the primary particles to a different polarity and aggregating the primary particles are as follows.
It may be performed one or more times.

As described above, the first method can easily control the particle size, selectively bond the low softening point particles and the high softening point particles, and further, can fuse the particles most strongly. No desorption occurs even under a mechanical strainer in the developing unit. On the other hand, in the second and third methods, adhesion between particles becomes insufficient, and the cost is disadvantageous as compared with the first method.

FIG. 7 shows a toner according to a second embodiment of the present invention, in which a plurality of particles containing a resin having a low softening point are agglomerated to form irregular particles, and a resin having a high softening point is coated around the particles. FIG. 3 is a conceptual diagram of a method for producing a toner. First, in order to obtain irregular particles containing a resin having a softening point, a method of coagulating and fusing substantially spherical particles obtained by emulsion polymerization, suspension polymerization, etc. It is possible to adopt a method in which a solvent or a gas is released by heating to form a concave portion.

As a method of coating the periphery of the irregular particles with a resin having a high softening point, there is a method of adhering particles containing a resin having a high softening point around the irregular particles and further fixing the particles. As a specific method, as shown in FIG. 7A, a controlled aggregation state is formed by changing conditions for controlling dispersibility, such as PH and agitation speed, from a state of being uniformly dispersed in a liquid. Then, there is a method of fusion and integration. As another method of FIG. 7 (a), there is a method of forming an ordered mixture of particles in a powder state by a mixer and then integrating them by a mechanical method such as colliding in a high-speed air flow, or a method of forming a powder in a hot air flow. It is possible to use a method in which a body group is passed and welded.

As a method of integrating in a liquid, as shown in FIG. 7B, a method of electrostatically aggregating particles in a liquid can be used.

Further, as shown in FIG. 7 (c), there is also a method of forming a film by applying a liquid or gas around irregular particles, for example, a spray drying method, a liquid drying method, and a liquid curing method. Examples include a coating method, an in-situ polymerization method, a phase separation method, and an air suspension coating method. In this case, the periphery of the irregular particles has a shape close to a spherical shape with corners.

In general, the method shown in FIGS. 7A and 7B is more likely to be indeterminate than the method shown in FIG. 7C and has high cleaning properties. Further, of the methods shown in FIGS. 7A and 7B, the method of dispersing in a liquid and then coagulating and integrating is advantageous in that the mechanical strength is higher than the method of mechanically coagulating.

FIG. 8 and FIG. 9 show that a plurality of regions containing a high molecular weight or high softening point resin are present around particles containing a low softening point resin according to the third embodiment of the present invention, and A conceptual diagram of an electrophotographic toner and a method for producing the same, wherein a straight line (shown by a broken line) enveloping an outline on the outer peripheral side of a region of a resin having a high softening point does not intersect with an outer periphery of a region containing a resin having a low softening point. Is shown. 8 (a), (b), (c),
(D) is a conceptual diagram of the shape of the toner according to the third embodiment of the present invention. In the figure, the broken line is a straight line enveloping the outer contour on the outer peripheral side of the region containing the high softening point resin, and the broken line does not intersect with the outer periphery of the region containing the low softening point resin.

On the other hand, FIGS. 8 (e), 8 (f) and 8 (g) show that the number of resin regions having a high softening point is relatively small or the volume is small. This shows a state where it intersects with the outer periphery of the region containing the resin. Particles containing a resin having a low softening point have the shapes shown in FIGS.
(E) and (f), even if they are substantially spherical,
As shown in FIGS. 8B, 8C, and 8G, an irregular type may be used, but an irregular type is more preferable in consideration of cleaning properties.

8 (a), 8 (b), 8 (c), and 8 (d), the method for producing the particles containing the low softening point resin and the particles containing the high softening point resin is not only a polymerization method but also a pulverization method. It may be. As a method for forming a region containing the high softening point resin around the region containing the low softening point resin, the same method as in the first embodiment of the present invention can be adopted.

That is, as shown in FIG. 9A, from the state where the particles containing the low softening point resin and the particles containing the high softening point resin are uniformly dispersed in the liquid, the dispersibility such as PH and stirring speed is changed. By changing the control conditions, a controlled agglomeration state is formed and fused and integrated, or a mechanical method such as forming ordered mixture with a mixer in powder state and then colliding in a high-speed air stream And a method in which the powder group is passed through a hot air flow and welded. Among these methods, a method of aggregating from a state of being uniformly dispersed in a liquid forms a toner having the highest mechanical strength.

Among the methods of coagulation in liquid, FIG.
As shown in (b), electrostatic aggregation of both particles is also effective to increase the accuracy of the particle ratio. In order to prevent particles having a low softening point from adhering to each other regardless of whether they are in the air or water, it is effective to coat the low softening point particles in advance with a high softening point resin or an inorganic substance such as silica, zinc oxide, or titanium oxide. is there. Further, when the particles containing the low softening point resin are irregular, as shown in FIG. 9C, the production method is the same as that for the spherical particles.

FIG. 10 is an electrophotograph showing a fourth embodiment of the present invention in which particles containing a resin having a low softening point, all or a part of the outer periphery of which is coated with a resin having a high softening point, are agglomerated and integrated. FIG. 3 is a conceptual diagram of a toner and a method of manufacturing the toner. FIG. 10A shows a method of forming particles containing a resin having a low softening point, in which all or a part of the outer periphery is covered with a resin having a high softening point.
As shown in FIG. 10 (b), a shell is formed by applying a liquid or gas to spherical or irregular particles, and as shown in FIGS. 10 (c) and 10 (d), particles are adhered and further immobilized. The specific encapsulation method is the same as that described with reference to FIGS. Also,
Means for aggregating and integrating these can be obtained by the same method as that described with reference to FIG. Even in this case, the method of aggregating the particles in the liquid is more excellent in the case where the toner is formed, because it is less likely to be detached and crushed by mechanical stress.

Examples of the resin for the toner used in the present invention include styrene, styrene-acrylic copolymer, styrene-butadiene copolymer, polyester resin, epoxy resin and the like. As the coloring agent, inorganic pigments (natural, chromate, ferrocyanide, oxide,
Chlorides, sulfates, silicates, metal powders, etc.), organic pigments (natural dye lake, nitroso, azo, phthalocyanine,
Condensed polycyclic, basic dye lakes, mordant dyes, vat dyes, etc.), and dyes include water-soluble dyes and oil-soluble dyes.

Specific examples of the inorganic pigments include, for example, natural pigments such as ocher, chromates such as graphite, zinc yellow, barium yellow, chrome orange, molybdenum red and chrome green, and ferrocyan compounds such as navy blue. Oxides such as titanium oxide, titanium yellow, titanium white, red iron oxide, yellow iron oxide, zinc ferrite, zinc white, iron black, cobalt blue, chromium oxide, and spinel green; and sulfides such as cadmium yellow, cadmium orange, and cadmium red And silicates such as calcium silicate and ultramarine, metal powders such as bronze and aluminum, and carbon black.

Specific examples of the organic pigment include, for example, natural lakes such as Madalake, nitrone pigments such as naphthol green and naphthol orange, benzidine yellow G, Hanza yellow G, Hanza yellow 10G, Vulcan orange, lake red R, and lake. Red C, Lake Red D, Watching Red, Brilliantamine 6
B, pyrarozone orange, Bordeaux 10G, soluble azo type such as (formaroon), pyralozone red, para red, toluidine red, ITR red, toluidine red (Rake Red 4R), toluidine maroon, brilliant feast scarred, lake Bordeaux 5B,
Insoluble azo pigments such as azo pigments such as condensed azo pigments, phthalocyanine blue, phthalocyanine green, brominated phthalocyanine green, phthalocyanine pigments such as fast sky blue, and anthraquinone pigments such as sllen blue.
Condensed polycyclic pigments such as perylenes such as perylene maroon, perinones such as perinoo orange, quinacridones such as quinacridone and dimethylquinacridone, dioxazines such as dioxazine violet, isoindoline and quinophthalone, rhodamine 6B, lake Dye lakes such as Rhodamine Lake B, Malachite Green, etc., mordant dye pigments such as Alizarin Lake, vat dye pigments such as indathrene blue, indigo blue, anthantrone orange, fluorescent pigments, azine pigments (diamond black ), Green gold and the like.

Specific examples of the water-soluble dye include, for example, basic dyes such as -damine B, acid dyes, fluorescent dyes, and the like. Specific examples of the oil-soluble dye include fast orange R, oil red, oil yellow, and the like. Monoazo dyes,
Anthraquinone blue, anthraquinone violet,
And the like, azine dyes such as nigrosine and indulin, and basic, acidic and metal complex compound dyes.

Further, usable waxes include low molecular weight polyethylene, low molecular weight polypropylene, paraffin and the like. Examples of the charge control agent include an electron donating substance such as a nigrosine dye and a quaternary ammonium as a negative charge control agent, and an electron withdrawing substance such as a metal salt of a monoazo dye as a positive charge control agent. An external additive can be used for improving the fluidity of the toner, improving the environmental stability of the charge amount, improving the cleaning property, and removing the deposits on the photoreceptor. Examples include metal oxides such as silicon oxide, titanium oxide, zinc oxide, aluminum oxide, tin oxide, indium oxide, and cerium oxide; fatty acid metal salts such as stearic acid, calcium stearate, and lead sterate; and titanium Inorganic substances such as barium acid, strontium titanate and basic bismuth acetate, PMMA, styrene-acrylic copolymer, vinylidene fluoride and fluororesin such as tetrafluoroethylene can be exemplified.

Hereinafter, the effects of the present invention will be described more specifically with reference to various examples and comparative examples of the present invention.

Example 1 Styrene monomer 85 parts by weight Butyl acrylate 15 parts by weight Acrylic acid 3 parts by weight Sodium dodecylbenzenesulfonate 1 part by weight Benzoyl oxide 1 part by weight 20% anionic resin emulsion 30 parts by weight 10% anionic carbon black dispersion Liquid 40 parts by weight Cr meter negative charge control agent (CCA) 0.5 parts by weight Ion-exchanged water 150 parts by weight
-3 (manufactured by Nitsuker Corporation) and Nanomizer (LA3
0 = Cosmo Instrumentation Co., Ltd.)
, The pH was adjusted to about 4 with sodium hydrogen phosphate, and the temperature was increased to 70 ° C. while stirring at a stirring speed of 600 rpm. The state was maintained for 8 hours, and the polymerization reaction was carried out. A dispersion a containing particles A was obtained.

When the particle size of the spherical particles A was measured by a laser diffraction type particle size distribution analyzer, the volume average particle size was 1.3 μm. When the molecular weight of the particles A was measured by GPC, the number average molecular weight (Mn) was 2.1 ×
10 ⁴ , the weight average molecular weight (Mw) was 4.5 × 104. Furthermore, as a softening point, the flow start temperature was measured using a flow tester (CFT500, manufactured by Shimadzu Corporation). In measuring the flow start temperature,
After the resin particles were once melted, a pressure condition of 10 kgf / cm ² was used.

Next, 3 parts by weight of carbon tetrachloride, which is a chain transfer agent, was added to the above raw material, and dispersion, pH adjustment and polymerization were carried out under the same conditions as for the particle A, and a dispersion b containing the spherical particles B was obtained.
I got The volume average particle size of the particles B is 1.5 μm, and the molecular weight is 0.6 × 1 in number average molecular weight (Mn).
0 ⁴ , and the weight average molecular weight (Mw) was 1.3 × 10 ⁴ . The softening point was 94 ° C. Each of the dispersions a and b is cooled to 50 to 60 ° C., mixed at a ratio of 1: 1 and agitation speed is set to 200 rpm to aggregate two kinds of particles,
The secondary particles were heated to a temperature of 98 ° C. and aged to obtain particles having a volume average particle diameter of 6.4 μm. This was filtered and washed, and vacuum dried at 45 ° C. for 10 hours to obtain a toner. 1.0 wt% of hydrophobic silica was added to this toner and mixed with a Henschel mixer to obtain a final toner.

The toner thus obtained is equipped with a one-component contact developing device having a structure shown in FIG. 2, a heat roller heat fixing device having a surface temperature of 127 ° C. (nip width 7.5 mm), and a blade cleaning device. Used as developer for printer, process speed 105mm / sec,
Image output of lines and patches of 20 mm square solid black and halftone dots was performed. Set the image density of the solid black patch to M
When measured with an ACBETH-R918 reflection densitometer, a high density of 1.42 was obtained. The fixing strength of the halftone halftone patch image was measured, and good results were obtained. The fixing strength was measured by rubbing the toner fixing part with a fastness tester under the condition of 300 cloths, measuring the image density before and after the test with a reflection densitometer, and evaluating the ratio.

The evaluation of the toner adhesion in the developing device was performed by observing the surface of the developing roller and the charging blade with an SEM to determine whether or not the toner adhesion occurred on the charging blade and the developing roller. The cleaning property was evaluated by printing a predetermined number of sheets at a printing rate of 6%, and then determining whether there was a character memory or a streak-like defective image on the image. Following this, 3
When printing was performed on 10,000 sheets, images with stable density and uniformity were obtained from the initial stage to 15,000 sheets, there was no cleaning failure, and no toner was fixed on the developing device such as the charging blade. However, after that, white streaks occurred in the halftone image. At this time, when the developing device sleeve was observed by SEM, countless toner adhesion was observed.

This toner was mixed with a ferrite carrier having an average particle size of 60 μm at a weight ratio of 100: 4, and a two-component developing device, a heat roller heat fixing device having a surface temperature of 120 ° C. (nip width 7.5 mm), When the same evaluation as above was carried out using the toner as a developer of a printer having a process speed of 65 mm / sec equipped with a blade cleaning device, an image density of 1.45 was obtained and the fixing strength was high. When printing was performed on 60,000 sheets, an image of stable image quality was obtained from the initial to 40,000 sheets, but black spots were generated on the image due to toner aggregation.

Example 2 Except that carbon black was not used as a raw material,
Particles B ′ were obtained in the same manner as the particles B obtained in Example 1. The particle size of the particles B ′ was 1.5 μm, and the molecular weight and the softening point were the same as those of the particles B. Thereafter, the spherical particles A obtained in Example 1 were treated with an alkyl sulfate sodium salt (Sandet LNM: manufactured by Sanyo Chemical Industries) as an anionic surfactant,
The particles B 'were dispersed in an aqueous solution in which benzalkonium chloride (cation G50: manufactured by Sanyo Chemical Industries) as a cationic surfactant was dissolved at a weight ratio of 0.3% to the particles.

The two dispersions were mixed at a ratio of 1: 1.
After a lapse of 30 minutes while stirring at a rotation speed of 400 rpm, the liquid was sampled and observed with a laser microscope (manufactured by Lasertec). As a result, two to four particles aggregated, and almost half of the particles contained carbon. Particles. This is heated to 90 ° C. and maintained for 2 hours,
Particle C obtained by fusing the aggregated particles was obtained. The temperature of the dispersion liquid of the particles C was lowered to 30 ° C., the rotation speed was reduced to 200 rpm, and after 30 minutes, the obtained secondary particles C aggregated. Thereafter, the temperature is further increased to 95 ° C. and maintained for 4 hours, and the aggregated secondary particles of the particles C are fused and integrated,
It became the particle D.

After the temperature of the dispersion of the particles D was lowered to 30 ° C., the particles D were filtered, washed, and vacuum-dried at 45 ° C. for 8 hours. The particle diameter of the particle D is 6.4 μm in volume average particle diameter.
m. Using a Henschel mixer for the particles D,
Toner was finally obtained by adding 1.0% by weight of hydrophobic silica. This toner was used as a developer for a printer equipped with the one-component developing device used in Example 1, and a printing test was performed. As a result, the image density of the solid black patch was 1.18.
And the uniformity of the halftone was good, and a good fixing strength was obtained. Following this, when 50,000 sheets were printed, images with stable density and uniformity were obtained from the beginning to the end,
There was no cleaning failure, and no toner was fixed on the developing device such as the charging blade.

Example 3 A toner was produced in exactly the same manner as in Example 2 except that the carbon-containing particles B used in Example 1 were used instead of the particles B '. The obtained toner was filled in a printer equipped with the one-component developing device used in Example 1, and a printing test was performed. As a result, a clear image with a solid black patch having an image density of 1.42 was obtained. The fixing strength of the halftone halftone patch image was measured, and good results were obtained.

When the image was printed on 50,000 sheets subsequently, a stable image of uniform density and uniformity was obtained from the beginning to the end, there was no cleaning failure, and the toner was fixed to a developing device such as a charging blade. Was not seen either. Further, the toner was filled as a toner of a printer having a two-component developing device used in Example 1, and a printing test and an image evaluation were also performed. As a result, an image density of 1.45 was obtained, and the fixing strength was high. When printing was performed on 60,000 sheets, an image having stable image quality was obtained from the beginning to the end.

Example 4 and Comparative Example 1 In Example 3, the particle sizes of the particles A and B were changed by changing the polymerization time when the particles A and B were prepared. A toner was produced in the same manner as described above, in which particles were aggregated one by one to form particles C, and then particles C were aggregated to form particles D. The external addition amount of the hydrophobic silica was also set to 1% as in Example 1. The obtained toner was evaluated for fixing strength, fixing of the developing device, and cleaning property using a printer equipped with the above-described one-component developing device.
The results are shown in Table 1 below.

The fixing strength was measured using the above-mentioned measuring method, and the ratio of the image density before and after the test was 90% or more.
~ 90% was rated as △, and 85% or less as ×. The cleaning performance was evaluated by the presence or absence of a character memory or a streak-like defective image on the image after printing 30,000 sheets.

場合: No occurrence of 30,000 sheets, 1 to 3
The case of occurrence on 10,000 sheets was indicated by Δ, and the case of occurrence on 10,000 sheets or less was indicated by x.

Table 1 Particles A Particles B Particles Final Fixing Developing Cree Particle Size Particle Size A / B Average Strength Instrumenting (μm) (μm) Mixing Ratio Particle Size (μm) Stickiness Example 1 1.3 1.51 : 1 6.4 ０．８ ○ Example 4-1 0.7 0.8 1: 1 6.5 ○ ○ Example 4-2 0.5 0.5 1: 1 6.5 ○ ○ Example 4-3 0.3 0.3 1: 1 6.2 ○ ○ ○ Example 4-4 0.1 0.1 1: 1 6.3 ○ △ △ Comparative Example 1-1 0.07 0.08 1 : 16.4 ○ × △ Example 4-5 0.05 0.03 1: 1 6.1 ○ × △ Example 4-6 2.3 2.4 1: 1 6.4 ○ ○ ○ Example 4-7 3.1 2.7 1: 2 7.3 ○ ○ ○ Example 4-8 3.5 3.2 1: 2 7.5 ○ ○ ○ Example 4-9 4.8 4.6. 1: 2 9.7 △ ○ ○ Comparative Example 1-2 5.3 5.0 1: 2 12.3 × × Comparative Example 1-2 5.7 5.1 1: 2 12.1 × × ○ Implementation Example 5 In Example 3, the same anionic surfactant as that obtained by dispersing and dispersing the particles A was washed with the particles C in which 1 to 2 particles A and B were aggregated and fused at a ratio of 1: 1. Particles C were dispersed in an aqueous solution containing 0.3% by weight based on the solid content.
The particles B are dispersed in the dispersion, and the dispersion and the cationic surfactant dispersion are mixed at a solid content ratio of 1: 1.
The particles C and B were agglomerated for 30 minutes while stirring at a rotation speed of 400 rpm at 5 ° C. Furthermore, the liquid temperature is 90 ° C.
And kept for 3 hours to fuse and integrate the aggregated particles to obtain particles E.

Thereafter, the temperature was lowered to 30 ° C., the rotation speed of the stirring was reduced to 100 to 300 rpm, and after 30 minutes, the obtained particles E aggregated. Thereafter, the temperature was further raised to 95 ° C. and maintained for 4 hours, and the aggregate of particles E was fused and integrated to obtain particles F. Then, after the temperature was lowered to 30 ° C., the liquid in which the obtained particles F were dispersed was filtered, washed, and vacuum-dried at 45 ° C. for 8 hours. Particle F
Is a toner in which particles A and particles B are aggregated at a ratio of 1: 2.

In the same manner as above, nine types of toners were prepared by changing the ratio of particles A and B. The particle diameter was set to 6.2 to 6.8 μm in all of the volume average particle diameter, but this control was performed by adjusting the stirring speed. 1.0 wt% of hydrophobic silica was added to this toner, and mixed with a Henschel mixer. The obtained toner was evaluated in the same manner as in Example 4.
The results are shown in Table 2 below. Note that Comparative Examples 2-3 and 2-
Reference numeral 4 denotes a toner composed of an aggregate of only the particles A and the particles B. After the formation of the particles A or B, the agitation speed was reduced and the particles were aggregated.

Table 2 Particles A Particles B Particles Final Fixing Developing Cree Particle Size Particle Size A / B Average Strength Instrumenting (μm) (μm) Mixing Ratio Particle Size (μm) Stickiness Example 5-1 1.3 1.3. 5 1: 2 6.2 ○ ○ ○ Example 5-2 1.3 1.5 1: 4 6.5 ○ △ ○ Example 5-3 1.3 1.5 1: 6 6.4 ○ △ ○ Comparative Example 2-1 1.3 1.5 1: 7 6.6 ○ × ○ Example 5-4 1.3 1.5 2: 1 6.3 △ ○ ○ Example 5-5 1.3 1.3. 5 4: 1 6.4 △ ○ ○ Example 5-6 1.3 1.5 6: 6.8 △ ○ ○ Comparative Example 2-2 1.3 1.5 7: 1 6.5 × ○ ○ Comparative Example 2-3 1.3 1: 0 6.2 × ○ ○ Comparative Example 2-4 1.5 0: 1 6.6 ○ × ○ Example 6 and Comparative Example 3 In Example 3, particles A and B were used. Of chain transfer agent when preparing The amounts were changed, the molecular weights of particles A and B were changed, and these were aggregated in the same manner to prepare a toner. The particle diameters of the particles A and B and the final particle diameter of the secondary particles were the same (error range of 20% or less). Using a printer equipped with the one-component developing device used in Example 1, the fixing strength, the state of fixation in the developing device (microscopic observation), and the cleaning property were evaluated. The results are shown in Table 3 below.

Table 3 Particles A Particles A Particles B Particles B Fixing Development Cree Mn Mw Mn Mw Strength Instrumenting (× 10 ⁴ ) (× 10 ⁴ ) (× 10 ⁴ ) (× 10 ⁴ ) Fixing Example 6-1 9.8 89 0.3 0.7 O O O Example 6-2 4.5 21 0.2 0.5 O O O Example 6-3 1.6 2.8 0.3 0.7 O O ○ Example 6-4 1.3 3.2 0.8 1.5 ○ ○ ○ Comparative Example 3-1 2.1 4.5 1.2 2.7 × × ○ Comparative Example 3-2 0.8 1 0.5 0.6 1.3 ○ × ○ Example 7 In Example 3, yellow toner was replaced with benzidine yellow instead of carbon black, magenta toner was replaced with permanent rhodamine, and cyan toner was replaced with phthalocyanine blue. Got each. The molecular weight and softening point of each color toner were almost the same as those using carbon black as the colorant, and the particle size was about 6.5 μm. These toners were used in a color printer shown in FIG. 3 to output images. The process speed of this printer is 92 cm / sec, the fixing nip width is 7 mm, and the fixing temperature is 120 ° C.

The reflection density of the solid patch portion of each color was measured by using the reflection densitometer using a SIP filter.
Yellow: 1.72, Magenta: 1.81, Cyan:
A high image density of 1.74 was obtained. Further, the fixing property of the output image was evaluated. The fixability was evaluated by measuring the glossiness and color value of the fixed image. Gloss measurement is VG-
Using a 1001 type gloss meter (manufactured by Nippon Denshoku Co., Ltd.), a solid image was used as a sample, and the light projection angle and the light reception angle were 75 °, respectively, and the red, clean, and blue colors of yellow, magenta, and cyan toners were used. The gloss was measured. In general, a gloss of 25% or more gives a visually good color tone.

The color mixture was measured using a CR-100 type colorimeter (manufactured by Minolta), using the solid image used for the gloss measurement as a sample, and melting and mixing the color toner to check the color reproducibility. As a result, the glossiness of each color exceeded 28%, and sufficient color values were obtained even in a mixed color state. Furthermore, when a commercially available PET film was used as the transfer material, the transparency was high and the color value in a mixed color state was also good. Furthermore, even after outputting 50,000 images, there is no toner fixation or filming in the developing machine, and stable color and
A uniform image was obtained, and the cleaning property was also good.

Example 8 A polyester resin having a number average molecular weight Mn of 4.0 × 10 ³ , a weight average molecular weight Mw of 6.2 × 10 ³ and a softening point of 96 ° C. was used as a binder resin.
C. I. Pigment Yellow 17, magenta: C.I. I.
Solvent Red 52 and C.I. I. Using Solvent Red 49, cyan: phthalocyanine pigment, and black: carbon black, particles of four colors were produced by the following method.

That is, 93 parts by weight of resin, 5 parts by weight of colorant,
0.7 parts by weight of a quaternary ammonium salt-based CCA is premixed with a Nauter, melt-kneaded with a continuous feed kneader (PCM30 manufactured by Ikegai Iron Works), cooled, and then coarsely reduced to a particle size of about 1 to 2 mm using a hammer mill. The powder was then pulverized and then pulverized to a particle size of 40 μm or less by a pulverizer using an air jet method. The obtained finely pulverized product was classified to have an average particle size of 3.7.
μm color particles were obtained. Next, when producing particles A in Example 4-8 described above, particles A ′ having an average particle diameter of 3.5 μm were produced by removing carbon black from the raw materials. The molecular weight and softening point of the particle A 'were the same as those of the particle A.

The color particles and particles A 'obtained as described above were coagulated and integrated at a ratio of 2: 1 by the method shown in Example 5 to obtain four color particles. When this was observed with a color laser microscope (manufactured by Lasertec),
The color particles and the colorless particles were mixed approximately 2: 1 to form secondary particles. The volume average particle size of each toner is about 8.5
μm. 0.6 parts by weight of hydrophobic silica fine powder as a fluidity improver was added to 100 parts by weight of the toner to obtain a color toner.

This toner was charged into a developing device of a color printer similar to that in Example 7, and an image was output on plain paper. The same evaluation as in Example 7 was performed. As a result, the glossiness of each color exceeded 28%, and sufficient color values were obtained even in a mixed color state. When a commercially available PET film was used as the transfer material, the transparency was high and the color value in a mixed color state was good. Further, when an image of 50,000 sheets was output, a stable image free of image defects, toner fixation and cleaning failure was obtained until the end.

Example 9 (Raw material-1) Styrene-acryl copolymer resin 200 parts by weight (number average molecular weight 6000, softening point 94 ° C) Phthalocyanine blue 10 parts by weight Quaternary ammonium salt-based charged CCA 1 part by weight (raw material- 2) Only styrene-acrylic copolymer resin (number average molecular weight 19,800, softening point 147 ° C.) After mixing the above raw material 1 with a Nauter, melt-kneading with a heating kneader, solidifying by cooling, and jet-milling. The mixture was pulverized and classified using an airflow classifier to obtain particles G having a volume average particle size of 3 μm. On the other hand, raw material 2 (peased) was pulverized and classified to obtain particles H having an average particle size of 3 μm. Particles G were prepared by adding sodium alkyldiphenyl ether disulfonate, which is an anionic surfactant, to the particles G in an amount of 0.25% by weight.
Dispersed in the contained water to form a dispersion g. Further, the particles H were dispersed in water containing 0.25% by weight of distearyldimethylammonium chloride as a cationic surfactant with respect to the particles H, and mixed to form a dispersion h.

When the dispersion g and the dispersion h were mixed at a ratio of 1: 1 and a mixture was stirred at 40 ° C. for 30 minutes at a stirring speed of 450 rpm, an aggregate of particles was obtained. 93
C. and left for 5 hours for further cohesion and fusion. After filtering and washing this, vacuum drying was performed at 45 ° C. for 10 hours to obtain cyan particles I. The obtained cyan particles I had a volume average particle diameter of 6.8 μm, and were observed by a color laser microscope (manufactured by Lasertec Corporation). As a result, secondary particles were formed in which the color particles and the colorless particles were mixed approximately 1: 1. I was

Next, 0.8% by weight of hydrophobic silica was added using a Henschel mixer, and this was filled in a color printer as a cyan toner in the same manner as in Example 7 to evaluate the image. As a result, the glossiness of each color exceeded 28%, and a sufficient color value was obtained even in a mixed color state. When a commercially available PET film was used as the transfer material, the transparency was high. Further, even after the output of 50,000 sheets of images, there was no toner fixation or filming in the developing machine, an image with stable color and uniformity was obtained, and the cleaning property was good.

Comparative Example 4 A toner was prepared by a pulverization method using a raw material comprising 88% of a resin, 6 parts by weight of a coloring agent, 0.5 parts by weight of CCA, and 3.5 parts by weight of wax. As the binder resin, the following 5
Polyester resins of various molecular weights were used. Where M
w represents a weight average molecular weight, and Mn represents a number average molecular weight.

(1) Mn: 5.6 × 10 ³ , Mn: 1.1 × 10 ⁶ (2) Mn: 4.1 × 10 ³ , Mn: 3.0 × 10 ⁵ (3) Mn: 2. 8 × 10 ³ , Mn: 5.4 × 10 ⁴ (4) Mn: 2.2 × 10 ³ , Mn: 1.4 × 10 ⁴ (5) Mn: 2.0 × 103, Mn: 6.2 × the 10 ³ colorant, yellow: C. I. Pigment Yellow 17, magenta: C.I. I. Solvent Red 52, cyan: phthalocyanine pigment, black: carbon black,
CCA is made of quaternary ammonium and polypropylene wax.
A color toner was produced. The method for producing the toner is such that the raw materials are premixed with a Nauter, and melt-kneaded in a continuous kneader,
After cooling, coarsely pulverize to about 1 to 2 mm using a hammer mill,
m or less. The obtained finely pulverized product was classified to obtain color particles having an average particle size of about 7.5 μm. To the color particles, 1.2 parts by weight of a hydrophobic silica fine powder as a fluidity improver was added to 100 parts by weight of the toner to obtain a toner.

The obtained toner was filled in a developing device of a color printer in the same manner as in Example 7, and an image was output. Also,
A running test of 50,000 sheets was performed. Table 4 below shows the evaluation results of the fixing property and the fixing property of the toner manufactured using each resin in the developing device. In the table, ○ indicates that the toner was not fixed in the developing device after 30,000 sheets were printed, and X indicates that the toner was fixed and the uniformity of the image was deteriorated. The glossiness is 3 for yellow, cyan and magenta.
The average of the color measurement results was taken.

Table 4 Toner Resin Toner Fixing Gloss [%] (1) ○ 7 (×) (2) ○ 11 (×) (3) Δ19 (×) (4) × 32 (○) (4) × 46 (○) From Table 4 above, when a high molecular weight resin is used, adhesion to the developing device does not occur, but the glossiness is insufficient. When a low molecular weight resin is used, the glossiness is low. It is clear that there is no problem, but toner sticking to the developing device becomes a problem.

Example 10 20% anion resin emulsion 30 parts by weight 10% anionic carbon black dispersion 40 parts by weight Quaternary ammonium-based CCA 0.2 part by weight Emulsion wax 2 parts by weight Deionized water 150 parts by weight Was dispersed by a ball mill and a Nanomizer to form a dispersion of a resin emulsion.
Transferred to a 0 ml four-necked flask. Next, a monomer mixture having the following composition was added dropwise to the dispersion of the resin emulsion with stirring to obtain colloidal oil droplets having a particle size of about 2 μm.

Styrene monomer 85 parts by weight Butyl acrylate 15 parts by weight Acrylic acid 3 parts by weight Sodium dodecylbenzenesulfonate 1 part by weight Benzoyl peroxide 1 part by weight Carbon tetrachloride 3.5 parts by weight Adjust PH to about 4 with sodium hydrogen phosphate And stirring speed 3
The temperature was increased to 70 ° C. while stirring at 50 rpm, and 8
The polymerization reaction was performed while maintaining this state for a certain period of time to obtain irregular-shaped particles J. This is filtered, washed, and vacuum dried at 45 ° C for 1 hour.
After conducting for 0 hour and observing by SEM, potato-shaped irregular particles were found. When the particle size of the irregular particles J was measured by a laser diffraction type particle size distribution analyzer, the volume average particle size was 5.1 μm. GPC
The number average molecular weight (Mn) was 0.8 × 10 ⁴ and the weight average molecular weight (Mw) was 3.1 × 10 ⁴ . The softening point was 92 ° C.

Particles A and J obtained in Example 1
Was dispersed in water in which 0.3% by weight, based on the weight of the particles, of a polyoxyethylene fatty acid ester (Emulmin 180 manufactured by Sanyo Chemical Industries) as a nonionic surfactant was dissolved. The resulting two dispersions are mixed in a ratio of 3: 1 and mixed with 4
The mixture was stirred in a one-necked flask at 60 ° C. under the condition of 400 rpm, and after 30 minutes, a particle aggregate was obtained. When this was observed by SEM, secondary particles in a state in which the particles A of Example 1 were adhered without any gap were observed around the particles J.

The dispersion was heated to 99 ° C. with stirring, allowed to elapse for 4 hours, and fused and integrated. This was filtered, washed and vacuum dried to obtain a toner. The volume average particle diameter of the obtained toner was 7.1 μm. 9 μm
The above volume distribution was 8.0%. Using a Henschel mixer, 0.8% by weight of hydrophobic silica was added and mixed. The obtained toner is charged into a printer having a contact one-component developing device and a two-component developing device in the same manner as in Example 1,
When fixing was performed at a temperature of 127 ° C., the fixing property was high,
When the toner image was glossy and 50,000 sheets were printed, a stable image quality was obtained from the beginning to the end.
Neither adhesion of the toner to the developing device nor defective cleaning was observed.

Example 11 In Example 10, as a dispersant for particles A and J,
Dispersion, aggregation, fusion and integration, and addition of silica were performed in the same manner as in Example 10 except that 30% by weight of ethanol was used instead of the nonionic surfactant, to obtain a toner. The volume average particle diameter of this toner was 7.2 μm, and the volume distribution of 9 μm or more was 8.2%. This was put into a printer having the same contact one-component developer and a two-component developer, and 127
When fixing was performed at a temperature of ℃, the fixability was high, the gloss of the toner image was high, and printing was performed on 50,000 sheets.
An image having a stable image quality was obtained from the beginning to the end, and no toner was fixed to the developing device and no cleaning failure was observed.

Example 12 In Example 11, at the time of dispersing the particles J in ethanol, silica was previously added to the particles J by 5.0 as ethanol.
% Dispersed. When the particles J dispersed in ethanol were sampled and observed by SEM, silica was attached to the entire surface around the particles J. Other than the above, particles J and particles A were aggregated in the same manner as in Example 11 to obtain a toner. The volume average particle diameter of the obtained toner was 7.1 μm, and the volume distribution of 9 μm or more was 4.4%.

This toner was charged into a printer having a contact one-component developing device and a two-component developing device in the same manner as in Example 11,
When fixing was performed at a temperature of 127 ° C., the fixing property was high,
When the toner image was glossy and 50,000 sheets were printed, a stable image quality was obtained from the beginning to the end.
Neither adhesion of the toner to the developing device nor defective cleaning was observed.

Example 13 In Example 11, the particles A and L were dried in the dry state to obtain the following:
The mixture was mixed at a ratio of 1 and treated with an OM dither (manufactured by Nara Machinery) at 1000 rpm for 5 minutes to obtain secondary particles. When this was observed by SEM, it was found that the particles A were secondary particles having the particles A attached around the particles L without gaps. This was treated with a hybridizer (manufactured by Nara Machinery Co., Ltd.) at 10,000 rpm for 10 minutes, and fused and integrated to finally obtain particles having a volume average particle diameter of 7.3 μm. In addition, the volume distribution of 9 μm or more was 18%. Using a Henschel mixer, 0.8% by weight of hydrophobic silica was added to obtain a toner.

The obtained toner was filled in a printer having a contact one-component developing device in the same manner as in Example 1, and was fixed at a temperature of 127 ° C. The fixing property was high and the toner image was glossy. As a result of a printing test, an image having a stable image quality was obtained from the initial stage to 40,000 sheets, and neither toner sticking to the developing device nor cleaning failure was observed. However, since white stripes occurred in the halftone part after that,
Observation of the developing sleeve by SEM revealed that toner was fixed in one part.

Example 14 Styrene monomer 80 parts by weight Butyl acrylate 20 parts by weight Acrylic acid 2 parts by weight Sodium dodecylbenzenesulfonate 1 part by weight Benzoyl peroxide 1 part by weight 20% anionic resin emulsion 30 parts by weight 10% anionic carbon black dispersion Liquid 40 parts by weight Quaternary ammonium-based CCA 0.5 part by weight Carbon tetrachloride 3 parts by weight Ion-exchanged water 150 parts by weight The above raw materials were dispersed by a ball mill and a nanomizer and transferred to a 1000 ml four-necked flask.
Was adjusted to about 4 with sodium hydrogen phosphate, and the stirring speed was 4
The temperature was increased to 90 ° C. while stirring at 50 rpm, and 8
While maintaining this state for a time, a polymerization reaction was carried out to obtain a dispersion containing spherical particles K. When the particle size of the spherical particles K was measured by a laser diffraction type particle size distribution analyzer, the volume average particle size was 2.1 μm.

Next, the temperature was lowered to 60 ° C., and the stirring speed was reduced to 2
The particles K were aggregated to give secondary particles at 00 rpm, and the temperature was further raised to 98 ° C. to age the secondary particles. This was filtered and washed, and vacuum dried at 45 ° C. for 10 hours to obtain particles L having a volume average particle diameter of 0.5 μm. Particles L by GPC
The number average molecular weight (Mn) was 0.59 × 10 ⁴ , and the weight average molecular weight (Mw) was 1.1 ×
It was 10 ⁴ . The softening point was 94 ° C.

Particle A obtained in Example 4-1 was treated with didecyldimethylammonium chloride (cationic DDC80 = manufactured by Sanyo Chemical Industries) as a cationic surfactant, and particle L was treated with sodium dioctyl sulfosuccinate (anionic surfactant). Carabone DA72 = manufactured by Sanyo Kasei) at a weight ratio of 0.3% to the solid content, and the two dispersions were mixed at a weight ratio of the solid content of 3: 1 in a four-necked flask, and stirred at 67 ° C. and 400 rpm. After 30 minutes, secondary particles M in which particles L were aggregated were obtained. Particle M was sampled from the liquid and observed by SEM. As a result, spherical particles A of Example 4-1 were adhered without any gap around particles L, which were irregular particles.

The liquid in which particles M were dispersed was heated to 98 ° C. while stirring as it was, and after 4 hours, particles N in which particles M were fused and integrated were obtained. This is filtered, washed,
After vacuum drying, the particles N were separated. The particles N were particles having a volume average particle size of 6.7 μm. Using a Henschel mixer, 0.8% by weight of hydrophobic silica was added to obtain a toner. This was filled into a printer having a contact one-component developing device in the same manner as in Example 1, and fixing was performed at a temperature of 127 ° C. The fixing property was high, the toner image was glossy, and
When printing was performed on 10,000 sheets, images of stable image quality were obtained from the beginning to the end, and no toner was stuck to the developing device and no cleaning failure was observed. Example 15 In Example 14, particles L and A were used. Is dispersed in water by the nonionic surfactant polyoxyethylene
When using a polyoxypropylene block polymer (manufactured by Sanyo Chemical Industries), good results were obtained as in Example 14.

Example 16 In Example 8, four types of color irregular particles of yellow, cyan, magenta and black after pulverization were classified to obtain particles having an average particle size of 5.2 μm. This is called particles P1, P
2, P3 and P4. When forming the particles A of Example 4-1, the particle diameter was 0.7 μm without containing carbon black.
To obtain colorless transparent particles Q. Particles P1, P2, P3, P4
The particles Q were dispersed in an aqueous solution of a nonionic surfactant, polyoxyethylene / polyoxypropylene / block polymer, having a solid content of 0.3% by weight to form five types of particle dispersions.

The resulting particle dispersions P1 and Q, P2 and Q,
P3 and Q, and P4 and Q were mixed at a weight ratio of 1: 2, respectively, and held for 30 minutes while stirring at a rotation speed of a stirring blade of 600 rpm to form aggregated particles. Further increase the temperature to 95 ° C
And held for 4 hours to fuse and integrate the aggregated particles.
Each of them was washed with pure water, filtered, and dried at 45 ° C. for 10 hours to obtain four kinds of color particles. The obtained particles were irregular particles having an average particle size of 6.4 μm. Observation with a color laser microscope revealed that a colorless resin layer was formed around the color core particles without gaps.

1.3% by weight of hydrophobic silica was externally added to the obtained four color particles and charged in a developing device of a color printer in the same manner as in Example 7 to output a color image. The fixability was evaluated. As a result, the glossiness of all three colors exceeded 30%, the color reproducibility of the mixed color portion was good, and even when the PET film was used as the transfer material, the transparency of the color image and the color tone of the mixed color were good. there were. Further, even after the output of 50,000 sheets of image, no toner was fixed in the developing device, and a stable image with good uniformity was obtained.

Example 17 Polyester resin (number average molecular weight Mn: 4.0 × 10 ³ ,
(Weight average molecular weight Mw: 6.2 × 10 ³ , softening point 96 ° C.)
96.5 parts by weight and 3.5 parts by weight of a polypropylene wax were premixed with a Nauter and a continuous feed kneader (PC
After cooling, the mixture was cooled and coarsely pulverized to about 1 to 2 mm using a hammer mill, and then finely pulverized to a particle size of 40 μm or less by an air jet pulverizer. The obtained finely pulverized product was classified, and the average particle size was 5.
Colorless irregular particles R of 0 μm were obtained.

The particles R and the particles A of Example 1 were dispersed in the same surfactant as in Example 10 at a ratio of 1: 3, and were electrostatically aggregated in a dispersion to obtain secondary particles. . When the secondary particles were sampled from the dispersion and observed by SEM, it was found that the particles A of Example 1 were attached around the particles R without gaps. The temperature of the dispersion was raised to 94 ° C. while stirring, and the aggregated particles were fused and integrated to finally obtain particles S having a volume average particle size of 7.1 μm.

When the cross section of the particle was observed with a TEM, carbon was present only in a region having a thickness of about 1 μm around the particle. 0.9 wt% of hydrophobic silica was added thereto and mixed with a Henschel mixer to obtain a black toner. This black toner was put into a printer having a contact one-component developing device and a two-component developing device in the same manner as in Example 1, and was fixed at a temperature of 127 ° C .. The fixing property was high and the toner image had gloss. When printing was performed on 50,000 sheets, a stable image quality was obtained from the beginning to the end, and the toner was not fixed to the developing device and the cleaning was not defective. Example 18 The particles A of Example 1 The particles L ′ obtained in Example 14 without containing carbon were mixed at a weight ratio of 1: 2 and treated with an OM dither to obtain secondary particles. The molecular weight and softening point of the particles L ′ were the same as those of the particles L.
When this was observed by SEM, particles having a particle size of 1 to 1.5 μm were attached around the particles having a particle size of 5 to 7 μm without completely covering the surface.

This was mixed with a hybridizer at 1000
The mixture was treated under a condition of 0 rpm for 10 minutes, and was integrated by fusion to finally obtain particles having a volume average particle size of 7.0 μm. This is TE
When a cross section was observed with M, a carbon-containing region having a diameter of 1 to 1.5 μm was present around a particle having a particle size of 5 to 7 μm, and a straight line enveloping the outer shape of the outer periphery of the carbon-containing region was an inner core particle. Was located outside the outline. 0.8% by weight of hydrophobic silica was added thereto and mixed with a Henschel mixer to obtain a toner.

This toner was charged into a printer having a contact one-component developing device and a two-component developing device in the same manner as in Example 1, and
When the fixing was performed at a temperature of 27 ° C., the fixing property was high and the toner image was glossy. Then, when a printing test was performed, an image of stable image quality from the initial stage to 35,000 sheets was obtained. Thereafter, when the printing test was further continued, white streaks occurred in the halftone portion due to the adhesion of the toner to the developing device. In addition, horizontal streaks and memory which seemed to be defective in cleaning occurred. At this time, when the particle size of the toner in the developing device was measured, it was 6.6 μm.

Example 19 The particles A of Example 1-1 and the particles L 'formed without containing carbon black in Example 14 were used as nonionic surfactants, and polyoxyethylene / polyoxypropylene / block polymers were used as solids. The mixture was dispersed in a water-soluble manner containing 0.4% by weight of the mixture, and the two were mixed at a solid content ratio of 1: 2, and stirred in a 1000 ml four-necked flask at 60 ° C. and a rotation speed of 350 rpm for 30 minutes. Was obtained, and secondary particles were obtained. The temperature of the dispersion was raised to 99 ° C. with stirring, and the state was maintained for 3 hours. As a result, particles in which the secondary aggregated particles were integrated were obtained.

This was washed with pure water, filtered, dried at 45 ° C. for 10 hours, and finally obtained with a volume average particle size of 7.2 μm.
m particles were obtained. The volume distribution of 9 μm or more is 7.4.
%Met. When the cross section was observed with a TEM, a carbon-containing region having a diameter of 1 to 1.5 μm was present independently around the particle having a particle size of 5 to 7 μm, and the outline of the outer periphery of the content region was enveloped. The straight line was located outside the outline of the inner core particle. 0.8% by weight of hydrophobic silica was added thereto and mixed with a Henschel mixer to obtain a toner.

This toner was filled as a toner of a printer having a contact one-component developing device and a two-component developing device in the same manner as in Example 1, and printing was performed at a temperature of 127 ° C. When printing was performed on the sheet, an image of stable image quality was obtained from the beginning to the end, and no toner was fixed to the developing device and no cleaning failure was observed.

Example 19-2 A toner was prepared in the same manner as in Example 19, except that a surfactant aqueous solution preliminarily containing 5% by weight of silica was used as a surfactant for dispersing the particles L '. Dispersed particles L '
Was observed by SEM, and silica was uniformly adhered to the surface. The volume average particle diameter of the obtained toner was 7.2 μm. In addition, the volume distribution of 9 μm or more was 4.3%. When the cross section was observed with a TEM, a carbon-containing region having a diameter of 1 to 1.5 μm was present independently around the particle having a particle size of 5 to 7 μm, and the outline of the outer periphery of the content region was enveloped. The straight line was located outside the outline of the inner core particle.

To this, 0.8% by weight of hydrophobic silica was added and mixed with a Henschel mixer to obtain a toner. This was similarly filled as a toner for a printer having a contact one-component developing device and a toner for a two-component developing device, and evaluated. As a result, the fixability was high and 50,000 sheets were printed. Thus, an image having the following image quality was obtained, and no toner was fixed to the developing device and no cleaning failure was observed.

Example 20 In Example 19, the particles L 'and the particles A in Example 1-1 were used.
The mixing ratio of 1: 1, 3: 1, 4: 1, and 5: 1 was obtained, and particles obtained by aggregating and integrating two types of particles were obtained in the same manner.
When this was observed with a TEM, the particle size was 5 to 7 μm in all cases.
A particle having a particle diameter of 1 to 1.5 μm is embedded around the particle without completely covering the surface, and a straight line enveloping the outer contour of the outer peripheral particle is located outside the outer contour of the inner core particle. I was 0.8% by weight of hydrophobic silica is added to this,
The mixture was mixed with a Henschel mixer to obtain a toner.

This toner was charged into a printer having a contact one-component developing device and a two-component developing device in the same manner as in Example 1-1, and was fixed at a temperature of 127 ° C .. When printing was performed on the sheet, an image of stable image quality was obtained from the beginning to the end, and no toner was fixed to the developing device and no cleaning failure was observed. Further, the glossiness of the toner image was superior to that of Example 14.

Comparative Example 5 In Example 19, the particles L 'and the particles A in Example 1-1 were used.
The mixing ratio was set to 10: 1 and 20: 1, and particles obtained by aggregating and integrating two types of particles were obtained in the same manner. This is TEM
As a result of observation, in all cases, particles having a particle size of 1 to 1.5 μm are more sparsely embedded around the particles having a particle size of 5 to 7 μm than the toner of Example 20, and envelope the outer contour of the outer peripheral particles. The straight lines intersect the outline of the inner core particle. To this, 0.8% by weight of hydrophobic silica was added and mixed with a Henschel mixer to obtain a toner.

This toner was charged into a printer having a contact one-component developer and a two-component developer in the same manner as in Example 1, and
When fixing was performed at a temperature of 27 ° C., no cleaning failure was observed, the fixing property was high, and the gloss of the toner image was excellent. However, white patches were formed on a solid patch black portion and black on a white background after printing 5,000 sheets. Streaks occurred, and when the surface of the developing roller was observed by SEM, sticking of black toner was observed.

Example 21 In Example 16, particles P1, P2, P3, P4 and Q
Was changed to form a color toner. When the cross sections of these particles were observed with a TEM, all of the particles had a particle size of 5 to 5.
Particles having a particle diameter of 1 to 1.5 μm were sparsely embedded around the particles of 7 μm, and a straight line enveloping the outer contour of the outer peripheral particles was located outside the outer contour of the inner core particles. 1.3% by weight of hydrophobic colloidal silica was added thereto and mixed with a Henschel mixer to obtain a toner.

This toner was charged into a developing device of a color printer in the same manner as in Example 7, and 50,000 color images were output at a fixing temperature of 120 ° C., and the fixing strength, glossiness, and internal When the state of fixation of the toner to the toner was examined, the results shown in FIG. 5 were obtained. The fixing strength was determined to be the weakest of the three colors, and the number of sheets in which fixation occurred was determined to be the earliest, and the glossiness was the average value of the three colors.

Table 5 Particle E: Particle A ′ Fixing strength Gloss Fixing number of sheets No. No. 21-1 1: 1 Δ21 No occurrence. 21-2 2: 1 ○ 25 No generation. No. 21-3 3: 1 ○ 27 Not generated. 21-4 4: 1 ○ 30 No occurrence. 21-5 5: 1 ○ 33 46,000 sheets No. 21-6 6: 1 ○ 32 40,000 sheets In the same manner as in Example 1, a developer prepared by mixing a ferrite carrier having a particle diameter of 60 μm with a developing device of a printer equipped with a two-component developing device, and a replenishing toner As a result, images having a high fixing strength and a glossiness of 30% or more were obtained stably from the initial stage to 80,000 sheets, and image defects such as unevenness did not occur.

Comparative Example 6 In Example 21, each of P1, P2, P3 and P4 and the particles Q were mixed at 10: 1 and 20: 1 to obtain a color toner. When the cross sections of these particles were observed by TEM, all of the particles had a particle size of 1 to 5 μm around a particle of 5 to 7 μm.
The 1.5 μm particles were further sparsely embedded, and the straight line enveloping the outer contour of the outer peripheral particle intersected the outer contour of the inner core particle. To this, 0.9% by weight of hydrophobic silica was added and mixed with a Henschel mixer to obtain a toner.

This toner was charged into a developing device of a color printer in the same manner as in Example 7, and 50,000 color images were output at a fixing temperature of 120 ° C., and the fixing strength, glossiness of the fixed image, and the The state of adhesion of the toner to the toner was examined. As a result, in each case, the fixing strength was sufficient and the glossiness was 30.
%, But sticking to the developing roller occurred when the number of output sheets was 10,000 or less.

Example 22 The black particles B obtained in Example 1 were prepared by using the three colorants of yellow, magenta and cyan used in Example 3 in place of carbon in forming the particles B. Microcapsules were formed using the color particles of the color as core particles by the following method. The molecular weight of each particle is Mn:
6 × 10 ³ , Mw: 1.3 × 10 ⁴ , and softening point was 94 ° C.

Each of the core particles was dispersed in an aqueous solution in which 0.7 parts by weight of ethyl cellulose was dissolved with respect to 100 parts by weight of the core particles using a nanomizer to obtain a dispersion s. Next, the following raw materials were dispersed by a ball mill and a Nanomizer. This is designated as a dispersion t.

Styrene monomer 90 parts by weight Negatively chargeable charge control agent 0.5 part by weight Benzoyl peroxide 2 parts by weight Sodium lauryl sulfate 1.5 parts by weight Water 200 parts by weight Dispersion s and dispersion t are mixed, and 1000 ml of The mixture was transferred to a four-necked flask, the pH was adjusted to about 4 with sodium hydrogen phosphate, the stirring speed was set to 600 rpm, the temperature was increased to 70 ° C., and the polymerization reaction was performed for 8 hours. The obtained particles were colored particles having an average particle size of 1.7 μm. After collection, the cross section was observed with a TEM. As a result, a shell having a layer thickness of about 0.2 μm was formed. Thereafter, the pH was set to 7 and the stirring speed was set to 270.
rpm and agglomerate the particles to form secondary particles.
When the temperature was raised to 0 ° C. and the mixture was heated for 4 hours, fusion was integrated in an aggregated state. The resulting particles are filtered and washed,
Vacuum drying for 4 hours, four types of volume average particle size 7.2 μm
Potato-like irregular shaped color particles were obtained. 0.8% by weight of hydrophobic silica was added thereto and mixed with a Henschel mixer to obtain a toner.

This toner was charged into a developing device of a color printer in the same manner as in Example 7, and 80,000 color images were output at a fixing temperature of 120 ° C. The image density of the solid patch portion of each color is as high as 1.80 for yellow, 1.77 for magenta, and 1.81 for cyan, and the fixing strength of the fixed image is 90% or more and the glossiness is 30%. Was over.
Further, a uniform and stable image including a halftone was obtained until the end, and no toner was fixed in the developing device.

Example 23 Styrene-acrylic copolymer 1.0 part by weight (Mn = 48000, Mw = 20,000, softening point 138 ° C.) 0.02 part by weight of a negatively chargeable charge control agent Four one
500 ml each into a four-necked 000 ml flask, into which the black particles B obtained in Example 4-2 and the yellow, magenta, and cyan used in Example 7 instead of carbon when forming the particles B were used. Each of the three kinds of color particles obtained using the three color coloring agents of
While stirring at 00 rpm, 300 g of n-hexane is further added.
Was added dropwise.

When the obtained particles were observed with a TEM, capsules each having a particle size of about 1 μm and a shell thickness of about 0.1 μm were formed. After filtration and drying of these particles, each particle was dispersed in an aqueous solution in which 0.3% by weight of a polyoxyethylene fatty acid ester was dissolved using a Nanomizer. In addition, 30
The temperature was increased to 98 ° C. while stirring at 0 rpm, and maintained for 4 hours to aggregate and integrate the primary particles. Thereafter, filtration, washing with pure water, and vacuum drying (45 ° C., 10 hours) were performed to obtain three kinds of color particles.

Each particle has an irregular shape and a volume average particle size of 7.1.
７7.3 μm. 0.9 wt% of hydrophobic silica was added thereto and mixed with a Henschel mixer to obtain four types of color toners. This toner was charged into a developing device of a color printer in the same manner as in Example 7, and 80,000 color images were output at a fixing temperature of 120 ° C. The image density of the solid patch portion of each color is yellow: 1.76, magenta: 1.72,
Cyan: a high density of 1.75 was obtained, the fixing strength of the fixed image was 90% or more, and the glossiness exceeded 30%. In addition, a uniform and stable image including a halftone was obtained until the end, and no toner was fixed in the developing device.

Example 24 The black particles B obtained in Example 1 and a molecular weight of Mn = 48 were obtained.
000, Mw = 20000, spherical particles of a styrene-acryl copolymer having a softening point of 138 ° C. and a volume average particle size of 0.2 μm, respectively, and sorbitan fatty acid ester (IONET S20 = manufactured by Sanyo Chemical Industries) as a nonionic surfactant ,
It was dispersed in an aqueous solution containing 0.5% by weight based on the solid content. The two dispersions were mixed in a weight ratio of 1: 3 solids and mixed in four flasks at 50 ° C. and a rotation speed of 380 rpm.
After stirring for 2 minutes, secondary particles were obtained. This was heated to 100 ° C. to fuse and integrate the secondary particles.

The obtained particles U were spherical particles having an average particle size of 1.7 μm.
The capsule particles were completely covered with a shell having a thickness of about 0.2 μm around the carbon-containing core particles. The obtained particles U were again dispersed in a nonionic surfactant and stirred at a temperature of 70 ° C. and 180 rpm for 30 minutes, whereby a secondary aggregate of the particles U appeared. When the obtained secondary particles were sampled and observed with a color laser microscope, each particle was aggregated to form secondary particles having a particle size of 5 to 7 μm. The temperature of the dispersion was raised to 100 ° C., and the particles were fused and integrated to obtain particles V.

The particles V were mixed with a hybridizer using
The treatment was carried out at 5000 rpm for 17 minutes. The resulting particles were potato-like irregular black particles having an average particle size of 5.8 μm. In addition to this, PMMA particles having a diameter of 0.4 μm 0.5
Wt% and hydrophobic silica were further mixed with a 1.2 wt% Henschel mixer to obtain a black toner. This black toner was charged as a toner in a printer having a contact one-component developing device and a two-component developing device in the same manner as in Example 1, and was fixed at a temperature of 120 ° C. The fixing property was high and the gloss of the toner image was high. When printing was performed on 50,000 sheets, an image of stable image quality was obtained from the beginning to the end, and no adhesion of the toner to the developing device and no defective cleaning were observed.

Example 25 In Example 24, the mixing ratio of the black particles B to the spherical particles of the styrene-acrylic copolymer having a particle size of 0.2 μm was 20:
In the same manner as in Example 1, black particles were obtained. The obtained particles are spherical particles having an average particle size of 1.6 μm, and the cross section is T
Observation by EM revealed that carbon-free particles of about 0.2 μm were discontinuously embedded around the carbon-containing core particles. The obtained particles were again aggregated and integrated in the same manner as in Example 24, to obtain irregular black particles having a volume average particle size of 5.7 μm.

Then, 0.9% by weight and 1.2% by weight of PMMA particles and hydrophobic silica were mixed in this order with a Henschel mixer to obtain a black toner. When this black toner was put into a printer having a contact one-component developing device and a two-component developing device in the same manner as in Example 1, and was fixed at a temperature of 120 ° C., the fixing property was high, and the toner image had gloss, When printing was performed on 80,000 sheets, an image of stable image quality was obtained from the beginning to the end, and no toner was stuck to the developing device and no cleaning failure was observed.

[0144]

As described above, according to the first aspect of the present invention (claim 1), the first particles mainly composed of a resin having a low softening point, and the first particles are coagulated and integrated with the first particles. According to the second aspect (Claim 2) of the present invention, by including the second particles mainly composed of a resin having a higher softening point than the resin having a reduced softening point, Amorphous core particles formed by coagulating and fusion-bonding a plurality of particles containing a resin having a low softening point and containing two or more different resins, and the core particles continuously coated around the core particles. According to the third aspect of the present invention (Claim 3), by including a resin layer having a higher softening point than that of the resin having a softening point, it further contains two or more resins having different softening points, and has a low softening point. Amorphous core particles containing the above resin and a softening point higher than the lower softening point resin formed around the core particles A toner including a plurality of resin regions containing a resin, wherein a straight line enveloping the outer shape of the outer periphery of the plurality of resin regions does not intersect with the outer periphery of the core particle, thereby providing a fourth aspect of the present invention ( According to claim 4), a resin having a lower softening point than a resin having a high softening point, wherein the resin contains two or more kinds of resins having different softening points and at least a part of the outer periphery is covered with the resin having a high softening point. By agglomerating and integrating a plurality of particles, firstly, it is possible to fix to a transfer material with low energy, secondly, good cleaning property, and thirdly.
Fourth, it is possible to obtain a long-life electrophotographic developer capable of obtaining a good full-color image.

[Brief description of the drawings]

FIG. 1 is a schematic conceptual diagram of an electrophotographic process.

FIG. 2 is a schematic cross-sectional view of a contact one-component developing device used for evaluating characteristics of the electrophotographic developer of the present invention.

FIG. 3 is a schematic cross-sectional view of a color printer used for evaluating characteristics of the electrophotographic developer of the present invention.

FIG. 4 is a schematic sectional view of a developing unit of a color printer used for evaluating the characteristics of the electrophotographic developer of the present invention.

FIG. 5 is a schematic sectional view of a fixing unit of a color printer used for evaluating the characteristics of the electrophotographic developer of the present invention.

FIG. 6 is a conceptual explanatory view of an electrophotographic developer according to the first embodiment of the present invention and a method for producing the same.

FIG. 7 is a conceptual explanatory view of an electrophotographic developer according to a second embodiment of the present invention and a method for producing the same.

FIG. 8 is a conceptual explanatory view of an electrophotographic developer according to a third embodiment of the present invention.

FIG. 9 is a conceptual explanatory view of an electrophotographic developer according to a third embodiment of the present invention and a method for producing the same.

FIG. 10 is a conceptual explanatory view of an electrophotographic developer according to a fourth embodiment of the present invention and a method for producing the same.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 photoconductor 2 charging device 3 exposure device 4 developing device 5 transfer device 6 transfer material 7 fixing device 8 cleaning device 9 static elimination device 10 cleaning blade 102 photoconductor drum 109 developing roller 110 ... Blade 111 ... Toner supply roller 112 ... Toner container 113 ... Nonmagnetic toner 114 ... Mixer 115 ... Recovery blade 116 ... Member 121 ... Baffle plate 123 ... Foaming material 200 ... Developing device 201 ... Photoconductor 202 ... Charging device 203 ... Laser exposure Apparatus 204 Blend cleaning apparatus 205 Static elimination lamp 209 Transfer apparatus 210 Fixing apparatus 211 Heating roller 212 Pressure roller 213 Image support 214 Heater lamp 215 Release agent coating member 216 Cleaning blade

──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Etsuko Miyamoto 70 Yanagimachi, Yuki-ku, Kawasaki-shi, Kanagawa Pref. Toshiba Intelligent Technology Co., Ltd. Examiner Yoshio Sugano (56) References JP-A-4-51251 (JP, A) JP-A-1-257857 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G03G 9/08

Claims (2)

(57) [Claims] 1. An amorphous core particle containing two or more resins having different softening points and containing a resin having a low softening point, and an amorphous core particle having a low softening point and partially formed around the core particle. A toner comprising a plurality of particles containing a resin having a higher softening point than the resin, wherein a straight line enveloping an outline on the outer peripheral side of the plurality of particles does not intersect the outer periphery of the core particles. Electrophotographic developer. 2. Particles containing two or more resins having different softening points, wherein at least a part of the outer periphery is covered with a resin having a high softening point, the resin containing a resin having a lower softening point than the resin having a high softening point. , A plurality of which are aggregated and integrated.